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Home My WebLink AboutMiscTECHNICAL Memorandum Client: City of Renton Project: Highlands 435 Pressure Zone Reservoirs and Emergency Generator Project File: REN 113.104.01.109 Project Manager: Kyle Pettibone, P.E. Composed by: Steve Nelson, L.HG., L.E.G. Reviewed by: Kyle Pettibone, P.E. Subject: Review of Existing Geologic, Hydrogeologic, and Geotechnical information Date: December 19, 2014 L_ St~;N.--;is;;-;,-1 EXPIRES 12/31/2014 12/19/14 12/19/14 Background The City of Renton (City) intends to construct a new reservoir on the site of its existing Highlands Reservoirs on the uplands east of central Renton. The existing reservoirs were constructed in 1941 and 1960, respectively. Preliminary designs indicate that the new reservoir would store 6.3 million gallons and with dimensions of approximately 170 feet by 250 feet and 25 feet high. A 2009 geotechnical report was completed by ZZA-Terracon to assess the site conditions and recommend foundation design and construction approaches for a new reservoir founded on the native subgtade material. This memorandum reviews the findings and recommendations of the geotechnical report and provides a summary of infiltration potential for possible on-site stormwater management. City Conditional Use permitting requires sufficient geotechnical assessment of the site to support the design and construction of the project and to evaluate the potential effect of construction and operation on geologic hazards. This memorandum includes RH2 Engineering, Inc.'s (RH2) review of the existing geotechnical report (ZZA-Terracon, 2009), and a review of available geologic mapping and boring logs. 12/19/20141:16PM J:\Data\REN\113-104\09 Permittirig\RE..~ Htghhnt Ba.ckground Gro Rrvi.l!'W Mano.docx Technical Memo re Review of Existing Geologic, Hydrogeologic, and Geotechnical Information December 19, 2014 Page2 Summary of Available Data The geotechnical report (ZZA-Terracon, 2009) summarized the findings of an on-site exploration program and review of available geologic mapping. Six test borings were drilled to depths of 32 to 40 feet below ground surface (bgs). Three borings were completed as monitoring wells at depths of 32, 38, and 39 feet. All of the borings encountered dense to very dense sand with silt and gravel from a few feet bgs to 40 feet bgs. No groundwater was observed in the soil boring or in the monitoring wells at the time of drilling in October 2008. The available geologic maps identified the native earth material at the site as dense glacial till. The geotechnical report evaluated potential geologic hazards at the site and concluded that the risk for liquefaction, erosion, and unstable slopes was very low. The report provided geotechnical design patameters and seismic risk conditions appropriate for the type of native earth materials, and the site location. The report assigned a Seismic Site Class C for the site and provided earth pressures allowable bearing values references, and seismic spectral acceleration values per the International Building Code (IBC) of 2006. Review of current geologic database included Washington Department of Natural Resources (W ADNR) mapping and Washington State Department of Ecology (Ecology) well log database. Per the geotechnical report, the W ADNR geologic mapping indicates that the site is underlain by glacial till. Boring logs within 1/, mile of the site consistently encountered dense sand, silty sand, and sandy silt with gravel, characteristic of glacial till. The depth to groundwater in nearby borings was greater than 50 feet bgs. The WADNR assigns a low risk for liquefaction, seismic shaking, erosion, and steep slope instability for the site, in concurrence with the conclusions ofZZA-Terracon (2009). Review of the City Sensitive Areas mapping, indicates that the site is within Aquifer Protection Zone 2, and that a few engineered slopes at the site (soil berms surrounding the existing reservoirs) are at slopes between 15 and 25 percent. No erosion or landslide hazards are identified at the site. Summary of Site Conditions Geologic conditions at the site are uniform and consistent with local conditions, consisting of dense glacial till to a depth of at least 50 feet. This soil type characteristically has a low permeability. The infiltration capacity is low, expected to be less than 0. 7 5 inches per hour; the site does not have a suitable soil type or area for on-site infiltration of stormwater or reservoir overflow. Groundwater exists at a depth of more than 50 feet bgs. The thick, low permeability soil provides substantial protection against the migration of accidentally released contaminants into underlying aquifers. The soil bearing capacity of the native glacial till appears sufficiently high to support the proposed reservoir without adverse settlement. Geologic hazards at the site are mapped as low. 12/t9/20141:17PM J:\D.w.\REN\113-104\09 Pamicticg\REN Highliac Background Geo Review Memo.doc: Technical Memo re Review of Existing Geologic, Hyclrogeologic, and Geotechnical Information December 19, 2014 Page3 Conclusions The existing geotechnical report and more recent mapping and soil boring information developed since the report was completed in 2009 contain sufficient geologic, hydrogeologic, and geotechnical information to support permitting, design, and construction of the proposed reservoir without the need for additional on-site investigation of soil or geologic properties. The geologic hazards at the site are sufficiently documented in existing and available geotechnical report and geologic information. The spectral seismic spectral acceleration values will need to be updated to reflect the 2012 IBC. Reference ZZA-Terracon, 2009, Geotechnical Report, City of Renton -Water Distribution System Storage Planning Study, Renton, Washington. Prepared for HDR Engineering, Inc. 12/19/20141:17PM J;\Dau\REN\113-104\09 Petmitting\REN Highlinc :&c~und GcoRrnc-w Mcmo.docx ~ ZZA-lrerracan 81085801 January 19, 2009 HOR Engineering, Inc. 500 108 1 " Avenue NE Bellevue, Washington 98004 Attention: Mr. Greg Pierson Subject: Geotcchnical Report City of Renton -Water Distribution System Storage Planning Study Renton, Washington Dear Mr. Pierson, This report presents the results of our geotechnical investigation for the City of Renton Water Distribution System Storage Study. Our scope of services included review of existing information, site reconnaissance, subsurface exploration, laboratory testing, geotechnical engineering analyses, evaluating potential geotechnical constraints for the project, and preparation of this repoti. These services were completed in accordance with the Subconsultant Agreement dated October 3, 2008. We understand that the City of Renton is planning to increase the storage capacity of its water system over the next 4 to 7 years. The City has identified the Highlands Site and Mount Olivet Site as two existing reservoir locations that can accommodate storage expansion for major service areas. We understand that the scope of the current study is limited to a planning level effort. The geotechnical conclusions and recommendations presented in this report are therefore preliminary in nature. PROJECT DESCRIPTION The location of the Highlands Site and existing site features are shown on Figure 1, Site and Exploration Plan. The site is currently occupied by l.5 and 2.0 MG below ground reservoirs, a 750,000 G elevated water tank, and a pump station. As currently planned, expansion of the Highlands Site would include the following. • Phase 1 construction of a 210 by 265 foot, 8.0 MG below ground reservoir in the undeveloped northern portion of the site. This reservoir would have an overflow elevation of 445.5 feet and a finished floor elevation of 425 feet. The latter elevation would place the finished floor 1 foot above to 7 feet below the existing ground surface. • New pump station located in the southern portion of the site to the west of the existing facility. 21905 641 • Avenue West Ste 100, Lynnwood, WA 98043 425-771-3304 Fax: 425-771-3549 ~ ZZA-lrerracan Water Distribution System Storage Study Renton, Washington 81085801 January 19, 2009 Page2 • Rech!orination facility located in the southern portion of the site. • Storm water detention vault located north of the Phase 1 below ground reservoir. This vault will extend about IO to 12 feet below the existing ground surface. • Several new 8 to 16 foot deep storm drain manholes. • Phase 2 demolition of the two existing below ground reservoirs and construction of a new 175 by 285 foot, 7.9 MG below ground reservoir. This reservoir would have an overflow elevation of 445.5 feet and a finished floor elevation of 425 feet. It appears that the latter elevation would place the finished floor at a similar elevation to the existing reservoirs, and about 11 to 17 feet below the existing ground surface around the perimeter of the new reservoir. • Phase 4 construction of a 72 foot diameter, 4.1 MG standpipe. The location of the Mount Olivet Site and existing site features are shown on Figure 2. The site is currently occupied by a 115 foot diameter, 3.0 MG standpipe located in the central portion of the site. Expansion of this site would involve demolition of the existing reservoir and Phase 3 construction of a new 140 foot diameter, 6.9 MG reservoir located at a similar location but slightly to the southwest of the existing reservoir. The new reservoir will have an overflow elevation of209.5 feet and a finished floor elevation of about 152 feet. The latter elevation would place the finished floor about I to 6 feet below the existing ground surface. A new retaining wall might be required on the southwest side of the new reservoir to provide access to this area. HIGHLANDS SITE SITE CONDITIONS Surface Conditions The Highlands site is bounded by NE 12'h Street on the south, and by residential property on the west, no11h, and east. The ground surface is inclined slightly downward to the north. Existing elevations range from 422 feet at the no11heast corner to 442 feet at the southeast corner. Existing vegetation consists of grass with evergreen trees distributed throughout the site, particularly in the no11hern undeveloped po11ion of the property. Numerous underground utilities are present at the site. Subsurface Conditions Subsurface conditions at the Highlands Site were explored by completing 6 test borings (Borings B-1 through B-6) at the locations shown on Figure 1, Site and Exploration Plan. Subsuiface exploration procedures and the logs of the explorations are presented in Appendix A. Laboratory testing procedures and results are summarized in Appendix B. 21905 641h Avenue West Ste 100, Mountlake Terrace, WA 98043 425-771-3304 Fax: 425-771-3549 ~ ZZA-lrerracon Water Distribution System Storage Study Renton, Washington 81085801 January 19, 2009 Page 3 The subsurface conditions encountered in Borings B-1 tluough B-6 were fairly consistent. These borings encountered topsoil and 2 to 5 feet of loose to medium dense silty sand at the surface, underlain by dense to very dense sand with varying amounts of silt and gravel. The medium dense to very dense sand was encountered to the maximum depth explored of39.5 feet below the existing ground surface. No groundwater was observed in the borings at the time of drilling. Groundwater observation wells were installed in Borings B-1, B-4, and B-5 to monitor groundwater levels following drilling. No groundwater was measured in these observation wells on October 23, 2008. Groundwater levels and soil moisture conditions should be expected to vary throughout the year due to fluctuations in seasonal precipitation, and other on-and off-site factors. CONCLUSIONS AND RECOMMENDATIONS General Based on our site reconnaissance, subsurface exploration, laboratory testing and geotechnical engineering analyses, we conclude that the project site is suitable for construction of the new reservoirs, pump station, rechlorination facility, storm water detention vault and storm drain manholes. This conclusion is based, in part, on employing proper design and construction practices to accommodate the conditions discussed below. The following sections of this repmt contain conclusions and recommendations regarding site preparation, excavations, permanent slopes, foundation considerations, floor slab support, subgrade walls, and hydrostatic uplift. Environmentally Critical Area Considerations Section 4-3-050 of the City ofRenton Municipal Code (RMC) describes the critical areas that are considered by the City of Renton during the development review process. This rep01t addresses the geologic hazards regulated under the RMC including steep slopes, erosion hazards, landslide hazards, seismic hazards, and coal mine hazards. The geologic hazard regulations apply to all nonexempt activities described in Section 4-3-050C5 on sites containing or located within 50 feet of the above hazards. Each geologic hazard is defined and described in greater detail on pages 13 through 17 of this report. The following sections briefly summarize these hazards as they pertain to the Highlands site. Steep Slopes The site does not contain either "sensitive slopes" or "protected slopes". 21905 64 1 " Avenue West Ste 100, Mountlake Terrace, WA 98043 425-771-3304 Fax: 425-771-3549 ~ ZZA-lferracan Erosion Hazards Water Distribution System Storage Study Renton, Washington 81085801 January 19, 2009 Page4 The site soils are defined by the USDA Soil Conservation Survey as "Arents, Alderwood material (AmC)" with slopes ranging from O to 6 percent. The erosion hazard for these soils is slight. Therefore, the site would be classified as a "low erosion hazard (EL)". Landslide Hazards The site is would be classified as "low landslide hazard (LL)." Seismic Hazards The site is not mapped as a high seismic area in the RMC maps in Section 4-3-0SOQ. In addition, the site would be classified as a "low seismic hazard (SL) due to dense to very dense soils present at the site at shallow depth. Coal Mine Hazards The site is not mapped as having any known mine hazards in Section 4-3-0SOQ. Therefore, the site is would be classified as a "low coal mine hazard." Site P1·eparation Site preparation should include the removal of all vegetation, root mass, organic soils, existing pavements and sttuctures, and any deleterious debris from construction areas including those locations where "structural fill" is to be placed. Any excavations that extend below finish grades should be backfilled with structural fill as outlined subsequently in this report. The borings at the Highlands site encountered 2 to 5 feet of loose to medium dense silty sand at the surface, underlain by dense to very dense sand with varying amounts of silt and gravel. The loose silty sand should be removed from the limits of the new reservoirs, pump station, rechlorination facility and storm water detention vault, and for a minimum distance of 5 feet beyond the perimeter of these structures. After site demolition and stripping, we recommend that the new structure areas be proofrolled and compacted to a firm and unyielding condition in order to achieve a minimum compaction level of95 percent of the modified Proctor maximum dry density as determined by the ASTM: D-1557 test procedure. Proofrolling should be accomplished with a heavy compactor, loaded double-axle dump truck, or other heavy equipment under the observation of a representative from our firm. Areas where loose surface soils exist should be removed and replaced with structural fill. The need for or advisability of proofrolling due to soil moisture conditions should be determined at the time of construction. We recommend that a 21905 641 • Avenue West Ste 100, Mountlake Terrace, WA 98043 425-771-3304 Fax: 425-771-3549 ~ ZZA-lrerracon Water Distribution System Storage Study Renton, Washington 81085801 Janua1y 19, 2009 Page 5 representative of our firm observe the soil conditions prior to and during proofrolling to evaluate the suitability of stripped subgrades. Eaithwork may be difficult during periods of elevated soil moisture and wet weather due to the moisture sensitive nature of the silty portions of the site soils. Subgrade soils that become disturbed due to elevated moisture conditions should be overexcavated to expose firm, non- yielding, non-organic soils and backfilled with compacted structural fill. We recommend that the earthwork po1tion of the project be completed during extended periods of dry weather, if possible. If earthwork is completed during the wet season (typically November through May), it may be necessary to take extra precautionary measures to protect subgrade soils. Excavations All excavations should be completed in accordance with applicable city, state, and federal safety standards. We anticipate that the site soils can he excavated using conventional earth moving equipment. Temporary Cut Slopes We anticipate that construction of the new below ground reservoirs and storm water detention vault might require temporary excavations up to 17 feet below existing grade. Temporary slope stability is a function of many factors, including the following: I. The presence and abundance of groundwater; 2. The type and density of the various soil strata; 3. The depth ofcut; 4. Surcharge loading adjacent to the excavation; and 5. The length of time the excavation remains open. It is exceedingly difficult under the variable circumstances to pre-establish a safe and "maintenance-free" temporary cut slope angle. Therefore, it should be the responsibility of the contractor to maintain safe slope configurations since the contractor is continuously at the job site, able to observe the nature and condition of the cut slopes, and able to monitor the subsurface materials and groundwater conditions encountered. It may be necessary to drape temporary slopes with plastic or to otherwise protect the slopes from the elements, and minimize sloughing and erosion. We do not recommend vertical slopes or cuts deeper than 4 feet if worker access is necessary. The cuts should be adequately sloped or suppm1ed to prevent injury to personnel from local sloughing and spalling. The excavation should conform to applicable Federal, State, and local regulations. Most of the soils which will be exposed in project excavations are consistent with the criteria for Type A soils presented in Chapter 296-155, Part N, Excavation Trenching and 21905 64'h Avenue West Ste 100, Mountlake Terrace, WA 98043 425-771-3304 Fax: 425-771-3549 ~ ZZA-lrerracon Water Distribution System Storage Study Renton, Washington 81085801 January 19, 2009 Page6 Shoring, of the Washington Administrative Code (WAC). Consequently, we recommend that maximum temporary slope inclinations of0.75H: lV be considered for preliminary planning purposes. Temporary Shoring It is possible that temporary shoring systems might be used for some project excavations. The lateral soil pressures acting on temporary excavation support systems will depend on the ground surface configuration adjacent to the excavation and the amount of lateral movement which can occur as the excavation is made. For support systems that are free to yield at the top at least one-thousandth of the height of the excavation, soil pressures will be less than if movements are limited by such factors as wall stiffness or bracing. We recommend that yielding systems be designed using an equivalent fluid density of 35 pounds per cubic foot (pcf) for a level ground surface. Similarly, we recommend that nonyielding systems be designed for a uniform lateral pressure of28H in pounds per square foot (psf), where His the depth of the planned excavation in feet below a level ground surface. The above recommended lateral soil pressures are based on a fully drained condition and do not include the effects of hydrostatic water pressures. In addition, the above values do not include the effects of surcharges (e.g., equipment loads, storage loads, traffic loads, or other Slllfaee loading). Hydrostatic water pressures and surcharge effects should be considered as appropriate. Construction Dewatering No groundwater was observed in the borings at the time of drilling. Construction dewatering is not expected to be a significant issue for the project. Permanent Slopes We recommend a maximum slope inclination of2H:1V (Horizontal:Vertical) for permanent cut and fill slopes. Permanent slopes should be hydroseeded or otherwise protected from erosion. Temporary erosion control may be necessary until permanent vegetation is established. Satisfactory perfo1mance of slopes is strongly affected by drainage and runoff. Care must be taken that drainage is not directed to flow over the slope face. Foundation Considerations Seismic Considerations The tectonic setting of western Washington is dominated by the Cascadia Subduction Zone formed by the Juan de Fuca plate subducting beneath the N011h American Plate. This setting leads to intraplate, crnstal, and interplate ea1thquakc sources. Seismic hazards relate to risks to people and damage to prope11y resulting from these three principle earthquake sources. 21905 641h Avenue West Ste 100, Mountlake Terrace, WA 98043 425-771-3304 Fax: 425-771-3549 ~ ZZA-lrerracan Water Distribution System Storage Study Renton, Washi.ngton 81085801 January 19, 2009 Page 7 We understand that the new structures will be designed in accordance with the procedures outlined in the 2006 International Building Code (IBC). Geotechnical eaithquake engineering input to development of the general design response spectrum of the IBC requires a site class definition, and short period (Ss) and I-second period (S1) spectral acceleration values. The USGS National Seismic Hazard Mapping Project (http://eghazmaps.usgs.gQy_/) computes the 2002 spectral ordinates (5 percent damping) at building periods of0.2 and 1.0 seconds for ground motions at the project site with a 2 percent probability of exceedance in 50 years as 1.419g and 0.484g. Therefore, we recommend for the 2006 IBC that S, and SI be assigned values of 1.419g and 0.484g, respectively. Based on the subsurface conditions encountered and published geologic literature, it is our opinion that a site class of C describes the average prope1ties of soils beneath the project site to a depth of I 00 feet. This designation describes soils that are considered very dense with a shear wave velocity between 1,200 and 2,500 feet per second, Standard Penetration Test values greater than 50, and an undrained sheai· strength greater than 2,000 psf. Liquefaction is the phenomenon wherein soil strength is dramatically reduced when subjected to vibration or shaking. Liquefaction generally occurs in saturated, loose sand deposits. It is our opinion, based on the site geology and the subsurface conditions encountered in the test borings, that the risk associated with liquefaction is low. Foundation,Suppo1t We recommend that the new reservoirs, pump station, rechlorination facility and storm water detention vault be suppmted on conventional spread footings. The spread footings should be founded on the native dense to very dense sand with varying amounts of silt and gravel, or on a zone of structural fill which extends down to the dense to very dense sand. All structural fill placed below the structures should consist of crushed rock meeting 2008 WSDOT Standat'd Specification Section 9-03.9(3) for crushed surfacing base course. The crushed rock should be compacted to at least 95 percent of the modified proctor maximum dry density (ASTM D-1557). We recommend 1hat continuous wall and isolated column footings have minimum widths of 1.5 and 2 feet, respectively. Exterior footings should have a minimum depth of embedment of 18 inches below adjacent grade for frost protection. Interior footings should be situated at least 12 inches below the structure floor. Spread footings for the new strnctures may be propo1iioned using the following allowable bearing values presented as a function of footing width. These values are for static loads and may be increased by one-third for loading conditions which include short-term live loads such as wind or seismic forces. 21905 641h Avenue West Ste 100, Mountlake Terrace, WA 98043 425-771-3304 Fax: 425-771-3549 ~ ZZA-lrerracan Footing Width(feet) 1.5 2.0 3.0 4.0 Wate,· Distribution System Storage Study Renton, Washington 81085801 January 19, 2009 Page8 Allowable Bearing Value(psQ 4,500 5,000 6,000 7,000 We estimate that the post-construction settlement of spread footings, founded as recommended, will be on the order of 1 inch or less. Most of this settlement is expected to occur rapidly as loads are applied. The soil resistance available to resist lateral foundation loads is a function of the frictional resistance which can develop on the base and the passive resistance which can develop on the face of below-grade elements of the structure as these elements tend to move into the soil. For spread footings founded on the native dense to very dense sand, the allowable frictional resistance may be computed using a friction coefficient of 0.35 applied to the ve11ical dead-load forces. The allowable passive resistance on the face of footings or other embedded foundation elements may be computed using an equivalent fluid density of 250 pounds per cubic foot (triangular distribution) for the on-site soils. Alternatively, passive pressures may be computed using an equivalent fluid density of 300 pounds per cubic foot for compacted structural fill, provided all of the fill soil extending out from the face of the foundation element for a distance at least equal to 2.5 times the embedded depth of the element has been compacted to at least 95 percent of the modified proctor maximum dry density (ASTM D-1557). The above coefficient of friction and passive equivalent fluid density values both include a factor of safety of about 1.5. Earth Anchors We understand that earth anchors might be considered to resist potential seismic overturning for the Phase 4, 4.1 MG standpipe. Several optional anchor systems could be considered including drilled and grouted earth anchors, and helical anchors. In our opinion, drilled and grouted earth anchors would be best suited for the project. We recommend that a minimum diameter of6 inches be assumed for the drilled anchor holes. A preliminary allowable soil to grout bond value of 4.5 kips per foot may be used for the native dense to very dense sand to estimate the anchor length. The anchor should have a minimum bond length of IO feet. A free stressing length of 5 feet should be provided to post- tension the anchors. As a result, soil to grout bond for the upper 5 feet of the anchor should be ignored when computing anchor pullout capacity. The estimated soil to grout bond value of 4.5 kips per foot should be confirmed for the specific installation method used by the contractor by completing an anchor load testing program. We recommend that performance tests be completed on two of the earth anchors to be identified by the engineer. Proof tests should be performed on each of the remaining earth 21905 64'" Avenue West Ste 100, Mountlake Terrace, WA 98043 425-771-3304 Fax: 425-771-3549 ~ ZZA-lrerracon Water Distribution System Storage Study Renton, Washington 81085801 January 19, 2009 Page9 anchors. The performance and proof tests should be completed in accordance with the procedures outlined in FHWA Geotechnical Engineering Circular No. 4, Ground Anchors and Anchored Systems, June 1999. After the anchors have been load tested, they should be post tensioned to a lock off load which removes all slack from the system and provides a seating load. We recommend that installation and load testing of the earth anchors be monitored by a qualified individual to document the installation procedures, and observe and interpret the load test results. Floor Slab Support We recommend that slab on grade floors be supported on the native dense to very dense sand with varying amounts of silt and gravel, or on a zone of structural fill which extends down to the dense to very dense sand. All structural fill placed below floor slabs should consist of crushed rock meeting 2008 WSDOT Standard Specification Section 9-03.9(3) for crushed surfacing base course. The crushed rock should be compacted to at least 95 percent of the modified proctor maximum dry density (ASTM D-1557). For the below ground reservoirs, stormwater detention vault, and storm drain manholes, the zone of crushed rock should have a minimum thickness of 12 inches of compacted base course to provide uniform suppo1i and protect the exposed subgrade soils from disturbance during subsequent construction activities. We estimate that the total settlement of slab on grade floors, designed and constructed as recommended above, will be less than I inch. Differential settlements across the structure are anticipated to be less than one-half inch over a distance of 40 feet. Settlements are expected to occur rapidly as loads are applied. We recommend that a representative from our firm observe the condition of the exposed subgrades prior to placing the base course to confirm that the bearing soils are undisturbed and consistent with the reconunendations presented in this report. Subgrade Walls ,Lateral Earth Pressures The lateral soil pressures acting on subgrade walls for below ground reservoirs and storm water detention vault will depend on the nature and density of the soil behind the wall, and the amount of lateral wall movement which can occur as backfill is placed. For walls that arc free to yield at the top at least one-thousandth of the height of the wall, soil pressures will be less than if movement is limited by such factors as wall stiffness or bracing. For those portions of the walls that are fully drained as described below, we recommend that yielding walls supporting horizontal backfill be designed using a static equivalent fluid density of 35 pcf(pounds per cubic foot), while nonyielding walls be designed using a static equivalent fluid density of 60 pcf. For 21905 641h Avenue West Ste 100, Mountlake Terrace, WA 98043 425-771,3304 Fax: 425-771-3549 f4ii ZZA-lrerracon Water Distribution System Storage Study Renton, Washington 81085801 January 19, 2009 Page IO those pm1ions of the walls that are not fully drained, we recommend that yielding walls supporting horizontal backfill be designed using a static equivalent fluid density of 80 pcf (pounds per cubic foot) (20 pcfsoil and 60 pcfhydrostatic), while nonyielding walls be designed using a static equivalent fluid density of 90 pcf (30 pcf soil and 60 pcf hydrostatic). Please note that these recommended lateral soil pressures do not include the effects of sloping backfill surfaces or surcharges such as traffic loads or other surface loading. Surcharge effects should be considered as appropriate. We understand that subgrade walls will be designed to resist seismic surcharge loads. For those portions of the walls that are fully drained, we recommend that a uniform seismic surcharge equal to 6H and 14H in pounds per cubic foot(rectangular distribution) be used for yielding walls and nonyielding walls, respectively. For those portions of the walls that are not fully drained, we recommend that a uniform seismic surcharge equal to 3H and 7H in pounds per cubic foot(rectangular distribution) be used for yielding walls and nonyielding walls, respectively. If drainage is provided for subgrade walls, we recommend that the drains consist of a minimum 6-inch diameter, rigid-wall, perforated drainpipe installed at the base of the wall. The pe1forated drainpipe should be embedded in a zone of coarse sand and gravel containing less than 2 percent fines (Gravel Backfill for Drains per WSDOT Section 9-03.12(4)). The zone of free-draining mate1ial should be at least 24 inches wide and extend from near the base of the footing to within one foot of the finished ground surface. The upper one foot of the backfill should consist of relatively impervious material to minimize the infiltration of surface runoff into the wall backfill. At appropriate intervals, the drainpipe should be connected to a tightline system leading to a suitable discharge. In addition, cleanouts should be provided for the drainpipe at appropriate intervals. All backfill for subgrade walls should be free of organic material, debris, or other deleterious material. Individual particle sizes should be less than 3 inches in maximum dimension. We recommend that all wall backfill be placed in lifts no greater than 10 inches in loose thickness and mechanically compacted to a firm, nonyielding condition. All backfill should be moisture conditioned to within ±2% of optimum moisture content for compaction as determined by the ASTM DJ 557 test method (modified proctor) prior to compaction. Backfill for subgrade walls should typically be compacted to between 90 and 92 percent of the modified Proctor maximum dry density. City of Renton compaction requirements should be followed if more stringent. Tite suitability of soils for use as backfill depends primarily on the gradation and moisture content of the soil when it is placed. As the amount of fines (that soil fraction passing the U.S. No. 200 sieve) increases, soil becomes increasingly sensitive to small changes in 21905 64"' Avenue West Ste 100, Mountlake Terrace, WA 98043 425-711-3304 Fax: 425-771-3549 ~ZZA-lrerracon Water Distribution System Storage Study Renton, Washington 81085801 January I 9, 2009 Page 11 moisture content and adequate compaction becomes more difficult, or impossible, to achieve. Generally, soils containing more than about IO percent fines by weight (based on that soil fraction passing the U.S. No. 4 sieve) cannot be compacted to a firm, non-yielding condition when the moisture content is more than a few percent from optimum. The optimum moisture content is that which yields the greatest soil density under a given compactive effo11. The results of our borings indicate that the site soils which will be encountered in project excavations consist primarily of sand and silty sand. These soils contain a significant amount of silt and will therefore be moisture sensitive. In our opinion, the site soils would be suitable for use as wall backfill only if moisture contents are adequately controlled. This may involve drying of over-optimum moisture soils by scarifying or windrowing the excavated material during extended periods of dry weather. In addition, soils which are dry of optimum might have to be moistened through the application of water and thorough blending to facilitate a uniform moisture distribution in the soil prior to compaction. We recommended that all stockpiled soils intended for use as wall backfill be protected from wet conditions with anchored polyethylene sheet plastic strong enough to withstand local wind conditions. We recommended that imported wall backfill material used for the project consist of "clean", free-draining pit-run sand and gravel meeting the requirements for "Gravel Backfill for Walls", WSDOT 9-03.12(2). It should be noted that the placement of backfill is, in many cases, weather-dependent. Delays due to inclement weather are common, even when using select granular fill. We recommend that ea11hwork be scheduled for the drier months, if at all possible. We recommend that a representative from ZZA Terracon be present during the placement of wall backfill to observe the work and perform a representative number of in-place density tests. In this way, the adequacy of the work may be evaluated as backfill placement progresses. Hydrostatic Uplift Hydrostatic uplift should be considered in design of the below ground reservoirs, storm water detention vault, and storm drain manholes if wall drainage is not provided for the full height of the subgrade walls. Hydrostatic uplift may be resisted by a combination of the dead weight of the structure mid soil friction resistance acting on the perimeter of the structure. Friction resistance may be computed using a coefficient of friction of 0.35 applied to the lateral soil pressures. 21905 64 1 • Avenue West Ste too, Mountlake Terrace, WA 98043 425-771-3304 Fax: 425-771-3549 ~ ZZA-lrerracan MOUNT OLIVET SITE SITE CONDITIONS Surface Conditions Water Distribution System Storage Study Renton, Washington 8!085801 January 19, 2009 Page 12 The Mount Olivet Site is bounded on the east by a slope which extends up to residential property, and on the n011h, west and south by slopes which extend down to Bronson Way NE and NE 3rd Street. The central pot1ion of the site where the new reservoir is planned is relatively level with elevations ranging from 154 to 158 feet. An existing pump building and an existing generator building are located in northwest corner of the relatively level area. Existing vegetation in the relatively level area consists primarily of grass. Various types of ground cover and trees are located on the adjacent slopes. Numerous underground utilities are present at the site. Subsurface Conditions Subsurface conditions at the Mount Olivet Site were explored by completing 3 test borings ( Borings B-7 through B-9) at the locations shown on Figure 2, Site and Exploration Plan. Subsurface exploration procedures and the logs of the explorations are presented in Appendix A. Laboratory testing procedures and results are summarized in Appendix B. Borings B-8 and B-9 were located in the vicinity of the new reservoir. The site was mantled by grass and topsoil at both locations. Boring B-8 encountered loose to medium dense silty sand to a depth of S feet, underlain by medium dense to very dense sand and silty sand. Boring B-9 encountered medium dense sand and silty sand directly below the grass and topsoil. The medium dense to very dense sand and silty sand was encountered to the maximum depth explored in the borings (34 feet below existing ground surface) Boring B-7 was located in the existing asphalt surfaced parking lot in the no11heast p011ion of the site. This borings encountered 2 inches of asphalt over medium dense to very dense sand with varying amounts of silt and gravel. Groundwater was observed in Borings B-7 and B-8 at depths of29 and 33 feet, respectively, below the ground surface at the time of drilling. No groundwater was observed in Boring B-9 at the time of drilling. A groundwater observation well was installed in Boring B-8 to monitor groundwater levels following drilling. Groundwater was measured in this observation well at a depth of28 feet on October 23, 2008. Groundwater levels and soil moisture conditions should be expected to vary throughout the year due to fluctuations in seasonal precipitation, and other on-and off-site factors. 21905 64'" Avenue West Ste 100, Mountlake Terrace, WA 98043 425-771-3304 Fax: 425-771-3549 ~ ZZA-lrerracon CONCLUSIONS AND RECOMMENDATIONS General Water Distl'ibulion System Storage Study Renton, Washington 8108580[ January l 9, 2009 Page 13 Based on our site reconnaissance, subsurface exploration, laboratory testing and geoteclmica! engineering analyses, we conclude that the project site is suitable for construction of the new 6.9MG reservoir. This conclusion is based, in part, on employing proper design and construction practices to accommodate the conditions discussed below. The following sections of this repo11 contain conclusions and recommendations regarding environmentally critical area considerations, site preparation, temporary cut slopes, permanent slopes, reservoir foundation considerations, and new retaining wall. Environmentally Critical Area Considerations The Mount Olivet property contains and is bounded by steep slope areas. As a result, environmental critical area considerations arc discussed in this repoti for the site. Section 4-3-050 of the City of Renton Municipal Code (RMC) describes the critical areas that arc considered by the City of Renton during the development review process. This report addresses the geologic hazards regulated under the RMC including steep slopes, landslide hazards, erosion hazards, seismic hazards, and coal mine hazards. The geologic hazard regulations apply to all nonexempt activities described in Section 4-3-050C5 on sites containing or located within 50 feet of the above hazards. Steep Slopes Section 4-11-010 defines a steep slope as a hillside, or portion thereof, which fill ls into one ofhl'o (2) classes of slope, sensitive or protected. A protected slope is defined as a hillside, or portion thereof; with an average slope, as identified in the City of Renton Steep Slope Atlas or in a method approved by the City, of forty percent (40%) or greater grade and having a minimum vertical rise offtfleenfeet (15~." A sensitive slope is defined as a hillside, or portion thereof, characterized by: (I) an average slope, as identified in the City of Renton Steep Slope Atlas or in a method approwd by the City, of twenty five percent (25%) to less than forty percent (40%); or (2) an avemge slope, as identified in the City of Renton Steep Slope Atlas or in a method approved by the City, offorty percent (40%) or greater with" vertical rise of less than fifteen feet (15~. abutting an avemge slope, as identified in the City of Renton Steep Slope Atlas or in a method approved by the City, o.ftwenty five percent (25%) to forty percent (40%). This de.finition excludes engineered retaining walls. 21905 641h Avenue West Ste 100, Mountlake Terrace, WA 98043 425-771-3304 Fax: 425-771-3549 ~ ZZA-lrerracon Water Distribution System Storage Study Renton, Washington 81085801 January I 9, 2009 Page 14 As shown in Figure 2, the Mount Olivet prope11y slopes downward from east to west to a relatively level area where the new reservoir will be located. From the level area, the site slopes downward to the north, west and south toward Bronson Way NE and NE 3rd Street. The site of the new reservoir is relatively level and would not be defined as a steep slope. Therefore, this area would not be subject to the steep slope provisions of the RMC. Sloped areas to the north, east, south and west of the reservoir site would be classified as protected slopes, having inclinations greater than 40 percent, with local sections up to 0. 7H: 1 V (140 percent), and greater than 15 feet in height, As shown in Figure 2, the only proposed development in sloped areas consists of an engineered retaining wall on the southwest side of the new reservoir. The location of the new retaining wall as currently shown would be classified as a protected slope, and subject to code provisions in Section 4-3-0SOJS -Protected Slopes. This Section provides the following: a. Prohibited Development: Development is prohibited on protected slopes. This restriction is not intended to prevent the subdivision or development of property that includes forty percent (40%) or greater slopes on a portion of the site, provided there is enough developable area elsewhere to accommodate building pads. b. Exceptions through Modification: Exceptions to the prohibition may be granted/or: i. Filling against the toe of a natural rock wall or rock wall, or protected slope created through mineral and natural resource recovery activities or public or private road installation or widening and related transportation improvements, railroad /rack installation or improvement, or public or private utility installation activities pursuant to subsection N2 of this Section, Modifications. ii. Grading to the extent that if eliminates all or portions of a mound or to allow reconfiguration of protected slopes created through mineral and natural resource recove,y activities 01· public or private road installation or widening and related transportation improvements, railroad track installation or improvement, or public or private utility installation activities, pursuant to subsection N2 of this Section, Modifications. c. Exceptions through Variance: Exceptions to the prohibition may be granted for construction, reconstruction, additions, and associated accesso1y s/rnclures of a single family home on an existing legal lot pursuant to a variance as stated in RMC 4-0-250BI. d. Exceptions through Waiver: Exceptions to the prohibition may be granted for installation of public 111ilities which are needed to protect slope stability, and public road widening where all I he following provisions have been demonstrated: i. The utility or road improvement is consistent with the Renton Comprehensive Plan, adopted utility plans, and the Trnnsportalion Improvement Program where applicable. ii. Alternative local ions have been determined lo be economically orjimctionally infeasible. iii. A geotechnical evaluation indicates that the proposal will not increase the risk of occurrence of a geologic hazard, and measures are identified lo eliminate or reduce risks. 21905 641h Avenue West Ste 100, Mountlake Terrace, WA 98043 425-771-3304 Fax: 425-771-3549 . ~ ZZA~lrerracan Water Distribution System Storage Study Renton, Washington 81085801 January 19, 2009 Page 15 iv. The plan/or the improvement is based on consideration of the best available science as described in WAC 365-195-905; or where there is an absence of valid scient/fic information, the steps in RMC4-9-250F are followed. Where the excepted activities above are allowed, the erosion control measures in subsection ./6 of this Section, Sensitive Slopes, Medium, High and Ve1y High Landslide Hazards, and High Erosion Hazards, shall also apply. Erosion Hazard Areas RMC Section 4-3-050Jlc defines erosion hazards as low or high using the following criteria: i. Low Erosion Hazard (EL): Areas with soils characterized by the Natural Resource Conservation Service (formerly U.S. Soil Conservation Service) as having slight or modernte erosion potential, and that slope less than fifteen percent (15%). ii. High Erosion Hazard (EH): Areas with soils characterized by the Natural Resource Conservation Service (formerly U.S. Soil Conservation Service) as having severe or velJ' severe erosion potential, and that slope more steeply than fifteen percent (15%). According to the National Resource Conservation Service(NRCS), the surficial soils on sloping areas to the no11h, west and south of the new reservoir site are classified as Alderwood and Kitsap soils, very steep (AkF) for slope inclinations ranging from approximately 25 to 70 percent. The NRCS describes these soils as having a hazard of water erosion that is severe to very severe. Therefore, the proposed retaining wall as currently shown on Figure 2 would be located in an area classified as a high erosion hazard (EH). The new reservoir location and the sloping areas to the east are classified by the NRCS as Everett gravelly sandy loam (EvC and EvD) with slope inclinations ranging from 5 to 15 percent and 15 to 30 percent, respectively. The NRCS describes these soils as having a hazard of water erosion ranging from slight to moderate, and moderate to severe, respectively. The new reservoir site would be located in an area classified as a low erosion hazard (EL). The sloping area to the east of the reservoir site would be classified as a high erosion hazard (EH). In order to pursue developments in high erosion hazard areas, development and design would be subject to the following provisions according to RMC Section 4-3-050J6: 6. Sensitive Slopes -Medium, High and Ve1y High Landslide Hazards -High Erosion Hazards: The following standards apply to deve/opmel!/ on sensitive slopes, 111edi11mlhighlve1y high landslide hazard areas, and high erosion hazard areas: a. Erosion Control Plans: Development applications shall submit erosion control plans consistent with subsection ./2 of this Section, Special Studies Required, and chapter 4-8 RMC, Permits and Appeals. b. Conditions of Approval: The Reviewing Official may condition a development proposal to achieve minimal site erosion, including. but not limited lo, timing of 21905 64'" Avenue West Ste 100, Mountlake Terrace, WA 98043 425-771-3304 Fax: 425-771-3549 ill ZZA-lrerracan Water Distribution System Storage Study Renton, Washington 81085801 Januaiy 19, 2009 Page 16 construction and vegetation stabilization, sequencing or phasing of construction, clearing and grading limits, and other measures. Mitigation plans may be required consistent with subsection F8 of this Section. c. On-Site Inspections: During construction, weekly on-site inspections shall be required at the applicant's expense. Weekly reports documenting erosion control measures shall be required. Landslide Hazard Areas RMC Section 4-3-050Jl b divides landslide hazards into the following four categories: i. Low Landslide Hazard (LL): Areas with slopes less than fifteen percent (15%). ii. Medium Landslide Hazard (LM): Areas with slopes between fifteen percent (15%) and forty percent (40%) and underlain by soils that consist largely of sand, gravel or glacial till. iii. High Landslide Hazards (LH): Areas with slopes greater than forty percent (40%), and areas with slopes between fifteen percent (15%) and forty percent (40%) and underlain by soils consisting largely of silt and clay. iv. Ve,y High Landslide Hazards (LV): Areas of known mappable landslide deposits. The new reservoir site is relatively level and would therefore be classified as a low landslide hazard (LL). Low landslide hazard areas do not require additional provisions per the RMC. The sloping areas to the north, east, south and west of the reservoir site generally have slope inclinations greater than 40 percent but do not contain areas of mappable landslide deposits. Therefore, these sloping areas would be classified as high landslide hazards (LH). The proposed retaining wall as shown in Figure 2 would be located in an area designated as a high landslide hazard. Developments in high landslide hazard areas are subject to the RMC provisions of Section 4-3-050J6 as described above in the Erosion Hazard Areas section of this repmt. Seismic Hazard Areas RMC Section 4-3-0SOJ!d divides seismic hazard areas into the following two categories: i. Low Seismic Hazard (SL): Areas underlain by dense soils or bedrock. These soils generally have site coefficients of types SJ or S2, as defined in the Uniform Building Code. ii. High Seismic Hazard (SH): Areas underlain by soft or loose, saturated soils. These soils generally have site coefficients of types S3 or S4, as defined in the Uniform Building Code. 21905 64'" Avenue West Ste 100, Mountlake Terrace, WA 98043 425-771-3304 Fax: 425-771-3549 ~ ZZA-lrerracon Water Distribution System Storage Study Renton, Washington 81085801 January 19, 2009 Page 17 The Mount Olivet site is generally underlain by medium dense to very dense sand and silty sand. Groundwater was observed at a depth of approximately 25 to 30 feet in dense to very dense soils. According to the Uniform Building Code, the project site would have a site coefficient ofS2 for dense soils. RMC Figure 4-3-050Q3d(i) is a map delineating known areas of high seismic hazards. The project site is not shown to be located in an area designated as a high seismic hazard according to the map. Based on the above information, the Mount Olivet site would be classified as a low seismic hazard (SL). Coal Mine Hazard Areas Coal mine hazard areas are divided into three categories by RMC Section 4-3-0SOJle: i. Low Coal Mine Hazards (CL): Areas with no known mine workings and no predicted subsidence. While no mines are known in these areas, undocumented mining is known lo have occul'l'ed. ii. Medium Coal Mine Hazards (CM): Areas where mine workings are deeper than two hundred feet (200? for steeply dipping seams, or deeper than fifteen (15) times !he thickness of the seam or workings/or gently dipping seams. These areas may be affected by subsidence. iii. High Coal Mine Hazard (CH): Areas with abandoned and improperly sealed mine openings and areas underlain by mine workings shallower than two hundred/eel (200? in deplhfor steeply dipping seams, or shallower lhanfifteen (15) limes the lhickness of the seam or workings/or genlly dipping seams. These areas may be affecied by collapse or other subsidence. According to RMC Figure 4-3-50Q3a(i), the project site is not mapped in an area designated as a moderate or high coal mine hazard. Therefore, the Mount Olivet site would be classified as a low coal mine hazard (CL). Site Preparation Site preparation should include the removal of all vegetation, root mass, organic soils, existing pavements and structures, and any deleterious debris from construction areas including those locations where "structural fill" is to be placed. Any excavations that extend below finish grades should be backfilled with structural fill as outlined subsequently in this repmt. Boring B-8 encountered a deposit of loose to medium dense silly sand to a depth of 5 feet, underlain by medium dense to very dense sand and silty sand. The loose silty sand should be removed from the limits of the new reservoir and for a minimum distance of 5 feet beyond the perimeter of the ring wall. 21905 64th Avenue West Ste 100, Mountlake Terrace, WA 98043 425-771-3304 Fax: 425-771-3549 f4 ZZA-lrerracan Water Distribution System Storage Study Renton, Washington 81085801 January 19, 2009 Page 18 After site demolition and stripping, we recommend that the new reservoir area be proofrolled and compacted to a firm and unyielding condition in order to achieve a minimum compaction level of 95 percent of the modified Proctor maximum dry density as determined by the ASTM: D-1557 test procedure. Proofrolling should be accomplished with a heavy compactor, loaded double-axle dump truck, or other heavy equipment under the observation of a representative from our firm. Areas where loose surface soils exist should be removed and replaced with structmal fill. The need for or advisability of proofrolling due to soil moisture conditions should be determined at the time of construction. We recommend that a representative of our firm observe the soil conditions prior to and during proofrolling to evaluate the suitability of stripped subgrades. Earthwork may be difficult during periods of elevated soil moisture and wet weather due to the moisture sensitive nature of the silty portions of the site soils. Subgrade soils that become disturbed due to elevated moisture conditions should be overexcavated to expose firm, non- yielding, non-organic soils and backfilled with compacted structural fill. We recommend that the earthwork portion of the project be completed during extended periods of dry weather, if possible. If earthwork is completed during the wet season (typically November tln·ough May), it may be necessary to take extra precautionary measures to protect subgrade soils. Temporary Cut Slopes We anticipate that construction of the new reservoir may require temporary excavations on the order of 4 to 12 feet below existing adjacent grade. Temporary slope stability is a function of many factors, including the following: I. The presence and abundance of groundwater; 2. The type and density of the various soil strata; 3. The depth of cut; 4. Surcharge loading adjacent to the excavation; and 5. The length of time the excavation remains open. It is exceedingly difficult under the variable circumstances to pre-establish a safe and "maintenance-free" temporary cut slope angle. Therefore, it should be the responsibility of the contractor to maintain safe slope configurations since the contractor is continuously at the job site, able to observe the nature and condition of the cut slopes, and able to monitor the subsurface materials and groundwater conditions encountered. It may be necessary to drape temporary slopes with plastic or to otherwise protect the slopes from the clements and minimize sloughing and erosion. We do not recommend vertical slopes or cuts deeper than 4 feet if worker access is necessary. The cuts should be adequately sloped or supported to prevent injmy to personnel from local sloughing and spalling. The excavation should conform to applicable Federal, State, and local regulations. Most of the soils which will be exposed in project excavations are consistent with the criteria for Type C soils presented in Chapter 296-155, Part N, Excavation Trenching and 21905 641 h Avenue West Ste 100, Mountlake Terrace, WA 98043 425-771-3304 Fax: 425-771-3549 ~ ZZA-lrerracon Water Distribution System Storage Study Renton, Washington 81085801 January 19, 2009 Page 19 Shoring, of the Washington Administrative Code (WAC). Consequently, we recommend that maximum temporary slope inclinations of 1.5H: 1 V be considered for preliminary planning purposes. Permanent Slopes We recommend a maximum slope inclination of2H:1V (Horizontal:Vertical) for permanent cut and fill slopes. Permanent slopes should be hydroseeded or otherwise protected from erosion. Temporary erosion control may be necessary until permanent vegetation is established. Satisfactory performance of slopes is strongly affected by drainage and runoff. Care must be taken that drainage is not directed to flow over the slope face. Reservoir Foundation Considerations Seismic Considerations The tectonic setting of western Washington is dominated by the Cascadia Subduction Zone formed by the Juan de Fuca plate subducting beneath the N01ih American Plate. This setting leads to intraplate, crustal, and inte1plate emthquake sources. Seismic hazards relate to risks to people and damage to property resulting from these three principle eaithquake sources. We understand that the new reservoir will be designed in accordance with the procedures outlined in the 2006 International Building Code (IBC). Geotechnical earthquake engineering input to development of the general design response spectrum of the IBC requires a site class definition, and short period (Ss) and I-second period (S1) spectral acceleration values. The lJSGS National Seismic Hazard Mapping Project (http://eqhazmaps.usgs.govD computes the 2002 spectral ordinates (5 percent damping) at building periods of 0.2 and 1.0 seconds for ground motions at the project site with a 2 percent probability of cxccedance in 50 years as 1.424g and 0.487g. Therefore, we recommend for the 2006 IBC that S, and SI be assigned values of 1.424g and 0.487g, respectively. Based on the subsurface conditions encountered and published geologic literature, it is our opinion that a site class ofD describes the average properties of soils beneath the project site to a depth of 100 feet. This designation describes soils that are considered stiff with a shear wave velocity between 600 and 1,200 feet per second, Standard Penetration Test values between 15 and 50, and an undrained shear strength between 1,000 and 2,000 psf. Liquefaction is the phenomenon wherein soil strength is dramatically reduced when subjected to vibration or shaking. Liquefaction generally occurs in saturated, loose sand deposits. It is our opinion, based on the site geology and the subsurface conditions encountered in the test borings, that the risk associated with liquefaction is low. 21905 641h Avenue West Ste 100, Mountlake Terrace, WA 98043 425-771-3304 Fax: 425-771-3549 ~ ZZA-lrerracan Setbacks From Adjacent Slopes Water Distribution System Storage Study Renton, Washington 81085801 January 19, 2009 Page 20 A slope which extends up to residential property is located in the eastern portion of the site. This slope appears to be inclined at approximately 2H: IV to 3H: I V(Horizontal to Vertical), and on the order of 40 to 50 feet high. The slope is fenced and heavily vegetated. No reconnaissance or subsurface explorations were completed for this portion of the site during the current study. As a result, it is not possible to evaluate the stability of the slope with respect to development of the reservoir site. However, we recommend that a minimum setback of 25 feet be assumed from the toe of the slope to the new reservoir for preliminary planning purposes. This setback should be measured from the toe of the p01iion of the slope which is inclined at 40%, or steeper. Slopes which extend down to Bronson Way NE and NE 3rd Street are located in the no1ihern, western and southern portions of the site. These slopes are typically inclined at I H: 1 V to 2H: IV and range up to 50 feet high. A formal stability analyses of these slopes was not completed. However, based on the results of a site reconnaissance of the slopes and the subsurface conditions indicated by the results of Borings B-8 and B-9, we recommend that a minimum setback of 25 feet be assumed from the crest of the slope to the new reservoir for preliminary planning purposes. This setback should be measured from the crest of the portion of the slope which is inclined at 40%, or steeper. The new retaining wall on the southwest side of the new reservoir will likely be located within the recommended setback distance as shown in Figure 2. In our opinion, it should be possible to develop a design for this retaining wall which can adequately mitigate the potential effects of slope stability. Foundation Support We understand that the reservoir will be supported on a perimeter ring wall foundation with interior footings supporting the roof. The tank floor will be at about elevation 152 feet. We understand that the base of the ring wall footing and interior footings will be at about elevation 146 and 148 feet, respectively. Preparation of the reservoir pad should include demolition of the existing reservoir including all existing foundation elements and piping. All structural fill placed below the reservoir should consist of crushed rock meeting 2008 WSDOT Standard Specification Section 9-03.9(3) for crushed surfacing base course. The crushed rock should be compacted to at least 95 percent of the modified proctor maximum dry density (ASTM D-1557). The ring wall and interior spread footings should be founded on the native medium dense to very dense sand and silty sand which is expected to be present at the base of the footing excavations. We recommend that the footings have a minimum width of 2 feet. The ring wall 21905 641 • Avenue West Ste 100, Mountlake Terrace, WA 98043 425-771-3304 Fax: 425-771-3549 ~ZZA-lrerracon Water Distribution System Storage Study Renton, Washington 81085801 January 19, 2009 Page 21 footing should have a minimum depth of embedment of 18 inches below adjacent grade for frost protection. Interior footings should be situated at least 12 inches below the reservoir floor. The spread footings may be propmtioned using the following allowable bearing values presented as a function of footing width. These values are for static loads and may be increased by one-third for loading conditions which include sho1t-term live loads such as wind or seismic forces. Footing Width<feet} 1.5 2.0 3.0 4.0 Allowable Bearing Value(psQ 4,500 3,000 4,000 5,000 We estimate that the post-construction settlement of the spread footings, founded as recommended, will be on the order of 1 inch or less. Most of this settlement is expected to occur rapidly as loads are applied. The soil resistance available to resist lateral foundation loads is a function of the frictional resistance which can develop on the base and the passive resistance which can develop on the face of below-grade elements of the structure as these elements tend to move into the soil. For spread footings founded on the native medium dense to very dense sand and silty sand, the allowable frictional resistance may be computed using a friction coefficient of0.35 applied to the vertical dead-load forces. The allowable passive resistance on the face of footings or other embedded foundation elements may be computed using an equivalent fluid density of 250 pounds per cubic foot (triangular distribution) for the on-site soils. Alternatively, passive pressures may be computed using an equivalent fluid density of 300 pounds per cubic foot for compacted structural fill, provided all of the fill soil extending out from the face of the foundation element for a distance at least equal to 2.5 times the embedded depth of the element has been compacted to at least 95 percent of the modified proctor maximum dry density (ASTM D-1557). The above coefficient of friction and passive equivalent fluid density values both include a factor of safety of about l.5. Earth Anchors We understand that eaith anchors might be considered to resist potential seismic overturning of the tank. Several optional anchor systems could be considered including drilled and grouted eaiih anchors, and helical anchors. In our opinion, drilled and grouted earth anchors would be best suited for the project. We reconunend that a minimum diameter of 6 inches be assumed for the drilled anchor holes. A preliminary allowable soil to grout bond value of3.5 kips per foot may be used for the native medium dense sand and silty sand to estimate the anchor length. The anchor should have 21905 64" Avenue West Ste 100, Mountlake Terrace, WA 98043 425-771-3304 Fax: 425-771-3549 ~ ZZA-lrerracon Water Distribution System Storage Study Renton, Washfngton 81085801 January 19, 2009 Page22 a minimum bond length of 10 feet. A free stressing length of 5 feet should be provided to post- tension the anchors. As a result, soil to grout bond for the upper 5 feet of the anchor should be ignored when computing anchor pullout capacity. The estimated soil to grout. bond value of 3 .5 kips per foot should be confirmed for the specific installation method used by the contractor by completing an anchor load testing program. We recommend that performance tests be completed on two of the earth anchors to be identified by the engineer. Proof tests should be performed on each of the remaining earth anchors. The performance and proof tests should be completed in accordance with the procedures outlined in FHWA Geotechnical Engineering Circular No. 4, Ground Anchors and Anchored Systems, June 1999. After the anchors have been load tested, they should be post tensioned to a lock off load which removes all slack from the system and provides a seating load. We recommend that installation and load testing of the earth anchors be monitored by a qualified individual to document the installation procedures, and observe and interpret the load test results. Reservoir Floor We recommend that the reservoir floor be supp011ed on the native medium dense to dense sand and silty sand, or on a zone of structural fill which extends down to the medium dense to dense sand and silty sand. All structural fill placed below the tank floor should consist of crushed rock meeting 2008 WSDOT Standard Specification Section 9-03.9(3) for crushed surfacing base course. The crushed rock should be compacted to at least 95 percent of the modified proctor maximum dry density (ASTM D-1557). We recommend that the zone of crushed rock have a minimum thickness of 12 inches to provide uniform suppo11 and protect the exposed subgrade soils from disturbance during subsequent construction activities. We estimate that the total settlement of the reservoir floor under the water load will be on the order of 2 to 3 inches at the center of the tank and I to I Ya inches at the tank perimeter. Settlements are expected to occur rapidly as loads are applied. New Retaining Wall We understand that a new retaining wall might be required on the southwest side of the new reservoir. This wall would retain fill placed to provide relatively level access to the area. Depending on the final height of the wall and its proximity to the top of the adjacent slope, a variety of different wall types could be utilized at this location. The following common wall types might be considered. ZZA Terracon is available to provide additional geotechnical inf01mation regarding the prefened wall type. 21905 64•• Avenue West Ste 100, Mountlake Terrace, WA 98043 425-771-3304 Fax: 425-771-3549 ~ ZZA-lrerracon Water Distribution System Storage Study Renton, Washington 81085801 January 19, 2009 Page23 • Rockery • Ecology block wall • Mechanically stabilized eat1h (MSE) wall • Conventional reinforced concrete wall USE OF THIS REPORT We have prepared this report for use by HDR Engineering and the City of Renton for the City of Renton Water Distribution System Storage Study. The data and report may be used for planning and estimating purposes, but our report, conclusions and interpretations should not be construed as a warranty of the subsurface conditions. If there are any changes in the grades, locations, configurations of types of facilities to be constructed, the conclusions and recommendations presented in this repo11 might not be fully applicable. If such changes are made, we should be given the opportunity to review our conclusions and recommendations and to provide written modification or verification of these recommendations. When the design has been finalized, our firm should review the final design drawings and specifications to see that our recommendations have been interpreted and implemented as intended. There are possible variations in subsurface conditions across the site and also with time. A contingency for unexpected conditions should be included in the project budget and schedule. Sufficient monitoring, testing and consultation should be provided by our firm during con- struction to confirm that the conditions encountered are consistent with those indicated by the explorations, to provide recommendations for design changes should the conditions revealed during the work differ from those anticipated, and to evaluate whether or not earthwork and foundation installation activities comply with the contract plans and specifications. Within the limitations of scope, schedule and budget, our services have been executed in accordance with generally accepted practices in this area at the time the report was prepared. No warranty or other conditions, express or implied, should be understood. ll1e conclusions and recommendations in this rep011 should be applied in their entirety. If there are any questions concerning the report or if we can provide additional service, please contact us. Respectfully submitted, ,{11/0'1 -......_) ~ i'-3 s)',.._<.f'<'<'----- James B. Thompson, Ph.D., PE Senior Principal tlake Terrace, WA 98043 425-771-3304 Fax: 425-771-3549 ,,; -r I I I I j I -I . I ., ---',, I -" ,,. ""·' Jl1-· ',._ I ---.,'k ... --,,,,-1-' 11 __f_'i_-,rw; I -~~''""'-''~ I] --,-j~ / -- E'.(.f't.ll,lj> ~ C<. 12· (1:,m/ 0Ulli1)10D. R($E~'O~ I "~ I __ _:__ ___ _J -~~---<--,, 1-' LEGEND: I I I I I !!\ i PROPOSED 7 .9 MG RESERVOIR (PHASE 2) OVERFLOW = 445. 5 FlNISHED FLOOR = 425.0 \ I I I I I t I 0 t:.· \ \t<.RESfJr,'OR O','f".RflQII' E:(. 1.5 M.G. RESERVOIR """" IS """' ·-=-hll B-51 ~o. • I -~A~ : ; ~"'j~ .... •.. . ·:~" l 1-)··· ~. · ..... ~.--woo,a.e,c --.-,-.-· .~I. J- -,-SD~ .-L ----· -so , 1----\_ -;-:-- --"',../I .. ' --. """" f y,·.,•r,:o I I 1· I I -SD -----=----- -""' ln"1B'f ~ lf-.. ·.f-16.2 JBT SB-1 BORING NUMBER AND APPROXIMATE LOCATION """"'" RMS JBf ,,......,., JBT !11 PnflttlJo 8H)8.S80l ... AS SHOWN ...... F~l.d>IO -1om,oa z ~ESlOENCES WATER SYST!:M 12· WATER TO RETIROJENT-~ - 60 •30 ·:_QI __ -60 -w~·_--;_ ~ -:~-1-~ :s I ~--Cl~,-----------"', ,--, ,,.::;i:ITTN FEET __;_-.. ...,._. w-~--w--------.-------w- 1.1nm v,1,ult. PROPOSED 8.0 MG RESERVOIR (PHASE l) OVERFLOW = 445.5 FlNISHED FLOOR = 425.0 B-2 611·· H:;l i'\.__oRAIN .:,.:';;!~~ ~-9 ~ --========-------- ~ -----====--- , \_INTERtiAL SEPARATION w,u iii VAVL j"·ORAlN B-4 ~( ~-~- TE~~9-. ...!IDL.M.J:L -~E.,, .f!4.0± ~ . . ( ·-......... B~SEMAP PROVIDED ;y HOR ENGINEERING INC. AND MODIFIE~-TERRACON SITE AND EXPLORATION PLAN lm1~, ~ ZZA-lrerracon WATER DISTRIBUTION SYSTEM STORAGE STUDY COf'l&u\ling Englnee!S and Scientists Highlands Site 21~&4tiA~W,S.100 l,lcur.!.a.tQfErra(:9.1',A!WU Renton, Washington PH.1425)111,3))4 FMl{J2511T1.3549 ' -- '- / / / / -/. ->'> (- _\ - '\' -\ \ ,\· --,0-·> ' ''" '' ' ' -< ', / 1L~:;~~~{~~/sE .. > EOOT: 1..a.;t·cc.~cs;,_;~ -......._,~ 1~-0J!: w,·5 ~---cc;i,,c NW . . / , / > / //. . .· ;; .. ---·>-~--I, ~:2 P.P( -ffl1 F!P1.__I____ :, ! ,.// ~Q // ,• -;>/r-C--~----------:_,~,-~--~~:~:,~t::~:_ '~ ;: .·· ... \ ~~\:' ( ~/ ,;:~A•J~<m.~_ / / _ e· / 'r;-{LD.D/lAU) ,/ / {} -._____ _/ CO.,CR[t[~~ Q . ,-··----. . - ,' <;.:J -~ ---------Aoc<rn~ /'it~· '. m~·11·~1~2-.e< // 1"o '', _ ~ u,~ ~ ~ l" --~------, ·'// --------L------~---"'~~0:----• i / / . :tR~J~~ ,' / -1-_ ;r-=:, .--EDG::CfASFl-'AJ.T '/, .1,::,,9 ~'.'./ '.4,.' ." : {NH 12, ,,., ,,,,;:,Q \20 - / ( -. . -/ __ ?1 . · -..t..\~1./@w~a ~39-' /-,-_ · y: ~-(, -·---_;z:• • fO?PPE.1~00 .,..-· ' , . -; -. --. . -fa. ./):_:{.' BOT. CF '.tT· 148.42 ~8"7 '/ / , / :------.:-.. -. ,. -. / , . , ~· 'P'i ~.j)~_J ~ / . · ' '-.._ (5: . _ , // ----. ll · · ~ ~ "t ~4 ,· , , ~-;.:· ~ ~ c):!Ruo~o C!iRa / ' /-. ---. -. --/ ~o.f-61 n\ ~-~~~qpu~ ----;---· ~, _,' -------== ~ M E:><5BJ " ' ·-\_' --~''100<ERY / ,· ,......-: -....._ ~ w ,,aoc TOPJ,,UT:149":7fl -'. , ' ,RELOCATE EX. QHP-------._ ·,;/" ~ , • ~ /],,_,,,,,", 102sv"--'', _:.-c'-,.ex·c~"' i , . --::~ ., ',.~Q:.t~~~;CR tllJl..'HJC,, -'ti, \ %. l', \ '\ \ \ \ ~.:,. 'o- it ·, . .._ _...,,9>.,,· \ \ I ....... b 11 0---_ ,, ,-:_-_:-\--. -•-\\' \_ \ \ .· \ ,,\r.. \ ,·" \ ...... i ' \ lr j "' e<'RCSOlll>R_ 'f""----··., - .. ··--------------I ~-·· i .·.·_ .. · ~ -~ JI (lou;,/11~c:/n>As,,rn} '>' ._ ' ' ·-...' -/ PROPOSED 'RESE:RVOIR , FOl,J,N_DATI_O~ '--\ \ ,f.ifj,/:--,_ \ __ .,WALi: ,"' '·, ". ·,, ·. ,::'<,}\\, PR<JPOSEO\ , , 7-'' i (~HASE 3) g~SERVO.IR /6.9 MG) \ '· . · ' REMOVE E --- ,, FINISHED ERFLOW = '209 -' ' ' ----X: fENCE DIAMET~~OOR -, 152:00_50 ' " -'-F> I / , / -; , -.,, / ~ N~V1S.Bl£?F}S / . i;' ~ .. , _, .~r~.Sfil___Yd__ --/ ;, / , ,"""'' ,,.,. {f~-~::;_.---1,;;, , --'$s.l ,TCfP:PE:1"<-9,1=" · '·-;~ ... £.~::,;ULT, ... ·,.. -. -.. ~~ ill£>!"'-""': »lp,,-, . . . . -~-----''s. " 'r, , , " % " ~~it1r:.1~i55M.·· ----:· .s\ a:i % -;;. '$ N,._. 1' "' (',l '.GP.~~!llill:152c4-9(S) -~-,, . ~,;.. 0::, ";• OOl.OF .. ',tT! 152//9 ·.. . • -. ,, 1;. P -- 40 /20 0 40 1···,· ~ I SCALE 'IN FEET ~N / ~~1iiii 'd) 0 {'J i ~ ~ '"' . . . _. . . . ~~~:t~;:r \. ' ·._ :;L'.t;ll~,\5~-~i~;-._ _ <' ',, --_ .. . . _ -. .' = _140.00' . ',:-, \ '-:c._ I .'------J -,_ --.:. ', ~'c:'s.A'.s'EMAPPROVIDED BY HOR ENGINEERING INC. AND MOtilFIED Bv'ZZA-TERRACON LEGEND: f'm;edl/.rrr. JBT _., 61085601 ~ ZZA·1rerraccn SITE AND EXPLORATION PLAN w WATER DISTRIBUTION SYSTEM STORAGE STUDY O<--.e,. -RMS AS SHOWN ~B-1 BORING NUMBER AND ,,_,, F?tith Consu~iflg Engineers and Scienli$tS Mt. Olivet Site JBT Fio2..dwn APPROXIMATE LOCATION _,,. """ 21'l0'i641hAwruiW.S19100~Terr«i1,W\900'3 Renton, Washington JBT 10Jml6 PH.(4~771-3:»I fJ.X.[,U5JT11,154& APPENDIX A FIELD EXPLORATION PROCEDURES AND LOGS APPENDIX A FIELD EXPLORATION PROCEDURES AND LOGS The field exploration for this project consisted of completing 6 borings at the Highlands Site on October 13 and 14, 2008, and 3 borings at the Mount Olivet Site on October 15, 2008. Approximate exploration locations are shown on the Site and Exploration Plans, Figure I and 2. Exploration locations were determined by measuring distances from existing site features with a fiberglass tape relative to a topographic map of the site provided by HOR Engineering, Inc. As such, the exploration locations should be considered accurate only to the degree implied by the measurement method. The approximate ground surface elevation at each exploration location was determined by interpolating from the information provided on the topographic plan. The following sections describe our procedures associated with the exploration. Descriptive logs of the explorations are presented in this appendix. The exploratory borings were advanced with a hollow stem auger, using a truck- mounted drill rig operated by an independent drilling company working under subcontract to our firm. A geotechnical engineer from our firm continuously observed the borings, logged the subsurface conditions encountered, and obtained representative soil samples. All samples were stored in moisture-tight containers and transported to our laborato1y for further visual classification and testing. Except where an observation well was installed in the boring, the borehole was backfilled with soil cuttings after completion of drilling, and the surface was patched with either bentonite clay or concrete. Throughout the drilling operation, soil samples were obtained at 2.5-to 5-foot depth intervals by means of the Standard Penetration Test (ASTM: D-1586). This testing and sampling procedure consists of driving a standard 2-inch outside diameter steel split spoon sampler 18 inches into the soil with a 140-pound hammer free falling 30 inches. The number of blows required to drive the sampler through each 6-inch interval is recorded, and the total number of blows struck during the final 12 inches is recorded as the Standard Penetration Resistance, or "blow count" (N value). If a total of 50 blows are shuck within any 6-inch interval, the driving is stopped and the blow count is recorded as 50 blows for the actual penetration distance. The resulting Standard Penetrntion Resistance values indicate· the relative density of granular soils and the relative consistency of cohesive soils. The enclosed boring logs describe the vertical sequence of soils and materials encountered in each boring, based primarily upon our field classifications and supported by our subsequent laboratory examination and testing. Where a soil contact was observed to be gradational, our logs indicate the average contact depth. Where a soil type changed between sample intervals, wc inferred the contact depth. Our logs also graphically indicate the blow count, sample type, sample number, and approximate depth of each soil sample obtained from the boring, as well as the laboratory tests performed on these soil samples. If groundwater was encountered in a borehole, the approximate groundwater depth, and date of observation, are depicted on the log. Groundwater depth estimates are typically based on the moisture content of soil samples, the wetted portion of the drilling rods, the water level measured in the borehole after the auger has been extracted, or through the use of an observation well. Groundwater observation wells were installed at three of the boring locations (Borings B-1, B-4 and B-5) at the Highlands Site and one of the boring locations (Boring B-8) at the Mount Olivet Site. Each well consisted of a length of slotted 2-inch PVC pipe placed in the bottom of the borehole. A blank PVC riser extended from the lower slotted section to the ground surface. Washed silica sand was utilized to backfill the annular space between the slotted interval and the borehole to allow entry of water into the well, while a mixture of bentonite clay and soil cuttings was used to backfill around the blank riser. A concrete surface seal and locking metal monument cover were placed at the surface. The groundwater level measured within each observation well subsequent to completion of drilling is indicated by a triangular symbol on the logs, along with the date of measurement. This information is also discussed in the text. LOG OF BORING NO. B-1 Paae 1 of 2 - CLIENT HOR Engineerina, Inc. SITE Highlands Site PROJECT City of Renton Renton, Washlnaton Water Distribution System Storage Study SAMPLES TE_S_!§ ___ WELL DESCRIPTION DETAIL _, .~ Cl 0 ~ g "' t ,11. ~ .; ,-· ,_ 0 Well ID = APQ-800 .; D'. ~ ffi~ z r ~ (/) UJ ':;@ "-BOREHOLE DIA.: 6in fl a, UJ ::, i? WELL DIA.: 1 In :. Q_ 0 >-0 ,_ z >-w (/) ::, /'.: UJ Q_ _, 18 a'.'\; Cl GROUND SURFACE ELEV.: 432 ft 0 ::, z D'. (/) a, Oo. Grass over 3 inches Topsoil over SIL TY - SAND, trace gravel, light brown, medium -- 2 430 -dense, damp - .: SIL TY SAND, with gravel, gray-brown -SM -s:1 SPl 52 9 .. with very slight Iron oxide staining, very - dense, moist -5---- ::: .·: - -:::.:. grades to trace gravel, no staining -SM S-2 SPT 5014" -._ .. <> -- :··· ... 10----- 1:-grades to gravelly, with tan silt pocket -SM S-3 SP 5015" 10 -·: -- 15--·--- -SM S-4 SP1 56 grades to moist to wet - - 20- I: ---- grades to with silt -SP S-5 ~p 50/5" 5 I ... .: =-CIIVI -.. : :.:· 25-- -,. ' - grades to wet .. -SP S-6 SPT 5015" SM ----.:· .. =.:·. - ,' 30-·.·. ',. :·~: -- '.: 32.5 399.5 - " -Continued Next Paae The stratification lines represent the approximate boundary lines between soil and rock types: in-situ, the transition may be gradual. WATER LEVEL OBSERVATIONS, ft if&zzA.:Jrerracon BORING STARTED 10-13-08 WL 'Sl. F,. BORING COMPLETED 10-13-08 '5l I" ----TRUCK\co. WL 21905 64th Avenue Wesl, Sle. 100 RIG EDI ----------Mountlake Terrace, WA 98043 WL V: (425) 771-3304 F: (425) 771-3549 LOGGED RMSI JOB# 81085801 LOG OF BORING NO. B-1 Paae 2 of 2 ------ CLIENT HOR Enaineerina, Inc. •"" ·------, ~ SITE Highlands Site PROJECT City of Renton Renton, Washington Water Distribution System Storage Study SAMPLES TESTS WELL (9 DESCRIPTION DETAIL .., -~ g al ),C ',11 ~ 0 ., ::;; "' ., .... !: >-"' ~ z r ~ (/) w ';~ ffi~ z n. [3 a, w 0 ::, iii ::;; ~ 0 li:g !;:Z >-w "' ::, w ~8 n (9 0 ::, z "' <l)Ol - SP S-7 $Pl 50/6" 6 :-f-----::: - :---1= _ 01VI \~ - 35-- . ·.t= . -1, ::.·-E - - I"'"; grades to with gravel :--.·-~ -SP S-8 SPl 74 :g ". -SM 39.5 392.5 _.·. - Boring completed at 39.5 feet on 10/13/08. No groundwater observed while drilling. No groundwater observed In plezometer on 10/23108. The stratification lines represent the approximate boundary lines between soil and rock types: in-situ, lhe transilion may be gradual. WATER LEVEL OBSERVATIONS, ft WzzA.:'fferracon BORING STARTED 10-13-08 WL '¥-J:Y: BORING COMPLETED 10-13-08 WL 'l. --1 21905 64th Avenue West, Ste. 100 RIG TRUCK I co. EDI Mountlake Ter<ace, WA 98043 ~--" RMS !JOB# WL V: (425) 771-3304 F: (425) 771-3549 LOGGED 81085801 LOG OF BORING NO. 8-2 Page 1 oJl._ ----------~-.---- CLIENT HDR Engineering, Inc. SITE Highlands Site PROJECT City of Renton Renton, Washington Water Distribution System Storage Study SAMPLES TESTS --------- (!) __J .S 0 ~ 0 DESCRIPTION a, >' ;f'. __J :;, " ~ 0 " cr: !:: >-cr: ~ l: ~ <n w ';~ ffi~ z ll. <n a, w :::, i? ll. 0 :;, a. 0 t;:g ~z >- Approx. Surface Elev.: 426 ft w <n :::, t w s:8 O:'t) (!) D :::, z 0: <n a, 0 <i Grass over 3 inches Topsoil over SILTY - .·.: 2.5 SAND, trace gravel, light brown, loose to -medium dense, damp 423.5 - SIL TY SAND, trace gravel, gray-brown, SM S-1 $Pl 81 7 very dense, damp - - 5- - ·.1:-. -- grades to gravelly, moist -SM S-2 $Pl 50/3" -- -·.1:-. 10-- I --- + -t,SM S-3 SPl 50/6" 6 1-GS -----··--- ·::. 15- - - - ---grades to trace iron oxide staining -SM S-4 SPl 50/5" - 20---- - 1: grades to trace silt with silty sand lenses, ·-SP S-5 SPl 5016" 11 .:. moist to wet - - ;. 25- - - -' · 1' grades to trace gravel -SP S-6 $Pl 50/5" - -·-·-· ··----~ - 30-- - - :•: 32.5 393.5 -- Continued Next Pa!!e The straUficalion lines represent lhe approximate boundary lines between soil and rock types: in-situ, the transition may be gradual. WATER LEVEL OBSERVATIONS, ft liflzzA.:Jrerracon BORING STARTED 10-13-08 WL '¥-I'-BORING COMPLETED 10-13-08 WL 'J. 1-l'. 21905 64th Avenue West, Sle. 100 RIG TRUCK I co. EDI WL Mountlake Te1race. WA 98043 RMS !JOB# --- V: (425) 771-3304 F: (425) 771-3549 LOGGED 81085801 LOG OF BORING NO. 8-2 Page 2 of 2 CLIENT HOR Engineering, Inc. ------------- SITE Highlands Site PROJECT City of Renton Renton, Washington Water Distribution Svstem Storage Studv SAMPLES TESTS g 6 .~ t'-~ DESCRIPTION Ol )C 0 "' ::. 0:: "' ~ !:: >-0:: ~ x ( "' w ';~ o::w z i "' "' w ~\e ::, 0 ::. (l_ 0 ti:3 >-w "' ::, ~ w :!!8 O::'IJ (!) 0 ::, z 0:: "'Ol 0 a. ----· ·1 grades to gravelly, trace cobbles, dense -SP S-7 SPl 48 5 ··1 ... - J::: - 35~ - ·_: ,:: -- - grades to very dense -SP S-8 SPl 5015.5' 39 387 ---~·-· Boring completed at 39 feet on 10113108. No groundwater observed while drilling. The stratification lines represent the approximate boundary lines between soil and rock types: ln-silu, the transition may be gradual. WATER LEVEL OBSERVATIONS, ft EzzA.:Jrerracon BORING STARTED 10-13-08 WL 'S1. J.! BORING COMPLETED 10-13-08 'l J1' ------- T-RUcKTco. WL 21905 64th Avenue West. Ste. 100 RIG EDI WL Mountlake Terrace, WA 98043 RMS JJOB# V: (425) 771-3304 F: (425) 771-3549 LOGGED 81085801 LOG OF BORING NO. B-3 Page 1 of 2 ------- CLIENT HDR Enr1lneerinu, Inc. ------~- SITE Highlands Site PROJECT City of Renton Renton, Washinr1ton Water Distribution Svstem Storage Study SAMPLES TESTS '-' i5 .£ ~ 0 DESCRIPTION <O i'i "#, _, :. "" ,-: I-,! "" >-0: ~ -ffi~ z r J: "' w '; 3l a. I-"' <O w :, ~ a. 0 :. a. 0 1-0 !:,:Z h Approx. Surface Elev.: 429 ft w "' :, ~ w a. ...J :;:8 '-' Q ::, z "' V)fil .. Cl 0. -~---:.:-:: Grass over 3" Topsoil over SIL TY SAND, - trace gravel, llghl brown, loose to medium - ·. 2 ,--ill - dense, damp - SIL TY SAND, wilh gravel,· gray-brown, -SM S-1 $Pl 46 7 dense, damp - -5- 1::-: - .-_:.· - .-'-grades to gravelly, very dense, moist SP S-2 SPT 55 -:· -SM - 1.-.i. 1-...!'. 10- --. - .: .. · .· -SM S-3 SPT 50/5" 8 - - 15----- grades to with gravel -sivl S-4 SPT 50/6" '- --20-- ------S-5 SPl 50/4" -. grades lo gravelly, with silt -SP 5 = SM" ---- - 25-- - - .. grades to trace silt -SP S-6SP 50/6" > ----- 30- .·._._ -- ·. 32.5 396.5 - Continued Next Paue The slrntifi:cation lines represent lhe approximate boundary lines between soil and rock types: in~situ, the transition may be gradual. WATER LEVEL OBSERVATIONS, ft EzzA.:Jrerracon BORING STARTED 10-13-08 WL Yl. 1~ BORING COMPLETED 10-13-08 - WL '1-I"-21905 64th Avenue West, Ste. 100 RIG TRUCK I co. ~ --Mountlake Terrace, WA 98043 RMS I JOB# WL V: (425) 711-3304 F: (425) 771-3549 LOGGED 81085801 LOG OF BORING NO. B-3 Paae 2 of 2 --- CLIENT HOR Enalneerlna, Inc. -·------- SITE Hfghlands Site PROJECT City of Renton Renton, Washlnaton Water Distribution System Storage Studv SAMPLES TESTS § ..J .£ DESCRIPTION g ~ -;f, ~ () " ~ " f--' f--O'. ~ -z z r J: "' w ';~ O'.W 0. I;: ~ Ill w Wf--:, ~ :z "-() f--0 f--Z >-w "' :, 1'.: w "-_, i2 :S'R (!) 0 :, z O'. "'"' T --grades to trace gravel, trace silt lenses -SP S-7 $Pl 80 6 -:: - 35-= --- 38.5 grades to gravelly 390_5 -SP S-8 SP 50/5" Boring completed at 38_5 feet on 10/13/08. No groundwater observed while drilling. ' The stratlfication lines represent the approximate boundary lines between soil and rock types: in.situ, the transition may be gradual. . WATER LEVEL OBSERVATIONS, ft irllzzA.:Jrerracon BORING STARTED 10-13-08 WL "1-1! BORING COMPLETED 10-13-08 WL v--21905 64th Avenue Wesl, Sle_ 100 RIG TRUCK)co. EDI --~ MounUake Terrace, WA 98043 WL V: (425) 771-3304 F: (425) 771-3549 LOGGED RMS I JOB# 81085801 o'. <!) "' LOG OF BORING NO. B-4 Page 1 of 2 ·-----------------~·-· CLIENT J--------'H..:.:D:..:R..:.::E..:.:n=glnc.=e-=-er,.,.in'-"1g._,,....:lccnc:..:. ______ --j------------···------·· ________ _ Highlands Site PROJECT City of Renton SITE Renton, Washington Water Distribution System Storage Study (9 g DESCRIPTION 2 WolllD~ ~ BOREHOLE DIA.: oc WELL DIA.: <9 GROUND SURFACE ELEV.: ... ·. i': 4 .'.·,.,: ·.·_ .. ,. ::_.': :: : ' Grass over 3" Topsoil over SIL TY SAND, trace gravel, light brown, medium dense, damp SILTY SAND,-trace·gf8vel 1 gray~brown, very dense, damp grades to with gravel grades to moist grades to with silt 61n 1 In 424ft 420 WELL DETAIL SAMPLES TESTS _J 0 co ., :;, >-O'. :i "' w ti: "' co w 0 :'E n. w "' :, ?: 0 :::, z 'if!. ~ ., >-' ... ';~ o::ffi z w,-. :, ... 0 ... z >-0. _J ~8 0:: 'I, mm 0 0. - - - -SM S-1 SPl 21 7 - 5----- -SM S-2SP1 50/6" 10----- =~M_ S-3 S_P_'l,_--+-50_/_5._5',_7__,_~, ·-- 15-· --- -SM S-4 SPl - 20----- -SP S-5 SP -SM - 25-= --- -SP S-6SPT 66 73 10 50/4" ~ SM -· ---1--!--+---+---J 30--- ·--- GS g 32.5 ~ Continued Next Page 1JI-T-he..l.s-t-,a-tif-ic-al-io_n_lin_e_s-,e-p.;re.;s;;.en;;.t;;.th.;e.;a;;;.p.;.pr;.;ox;;.im;.;.;.at.;e.ibo.;u_n_de-ry-lin_e_s __ .... __ ..i.__..i. _ _,__.._..,__.__..,__..i.,_..1. ___ -4 ~ between soil and rock lypes: in.situ, the transition may be gradual. WATER LEVEL OBSERVATIONS, ft llzzA.:lrerracon BORING STARTED 10-14-08 WL 'SJ_ r: BORING COMPLETED 10-14-08 "l ---·-----TRUCK\co WL 21905 64th Avenue West, Ste. 100 RIG EDI Mountlake Terrace, WA 98043 RMS !JOB# WL V: (425) 771-3304 F: (425) 771-3549 LOGGED 81085801 ,__ " "' 8 I § CLIENT SITE HOR Engineering, Inc. Highlands Site Renton, Washlnaton DESCRIPTION LOG OF BORING NO. B-4 Page 2 of 2 PROJECT City of Renton WELL DETAIL Water Distribution System Storage Study SAMPLES TESTS 5 -~ *' § ; ! ~ I ~i "'~ ~ fu ~ :; il' hl li:'3 ~z &~ o ~ ~ ~ ir wm ~8 o g_ ---------------------~. -~. +--_-+-cS~P-+S~-~71""s'="1p1+-----+~50~/~4'4' -'-1~0-+-+-----t .'.~\ -SM I< ::::::~ h .-.·-=.-:·. i ::; 38 _5 grades to gravelly 385 .5 \' ! :_: ·. ---=--"----------"-""'-'--=""4 Boring completed at 38.5 feet on 10/14108. No groundwater observed while drilling. No groundwater observed in piezometer on 10/23/08. 35--= --- -SP S-8SP1 C>IVI 50/6" •• ,_J_, __ l.-....______j'-----------' I 1i l-T-he"'s-1,-at-lfi-ca-ti-on_l_ln-es-,-.p-,e-s-en_t_th_e_a_pp-,o-x-im_a_te_b_o_un-d-ary-lin_e_s __ ..._ __ ..__...___. _ _.__..._...__..a.,_..,__..._ ___ -1 ~ between soil and rock types: in-situ, the transition may be gradual. ~ WATER LEVEL OBSERVATIONS, ft ~ WL"' j~ 13 WL 'l-tl' ~ WL 1 • ZZA.:Jrerracon1--B_O_RI_NG_ST_A_RT_E_D ____ 10:.....·1_4-_08__. BORING COMPLETED 10-14-08 21905 64th Avenue West, Ste.100 Mountlake Terrace, WA 98043 V: (425) 771-3304 F: (425) 771-3549 RIG TRUCK I co. EDI LOGGED RMS I JOB# 81085801 LOG OF BORING NO. B-5 Page_1 of 2 -----· CLIENT HOR Engineering, Inc. ------ SITE Highlands Site PROJECT City of Renton Renton, Washlnuton Water Dlstrlb_u!lcm System ~raue Study i § z 0 ~ I" WELL (!) DESCRIPTION DETAIL ...J 0 0 "' ...J :;; ¢! <,, Well ID= >-r :i "' n. BOREHOLE DIA.: 6 in I--"' ~ WELL DIA.: 1 In "-<.) w "' (!) GROUND SURFACE ELEV.: 441 ft 0 :, ic Grass over 2" Topsoil over SIL TY SAND, - trace gravel, gray-brown with slight iron --:··: oxide staining, medium dense, moist - -SM ·. ··: 5 436 - I> SIL TY SAND, with gravel, gray-brown, 5-- very dense, damp - I\ -- -SM I - - 1:, 10----· -·,· .' -SM ·,· - ) 15· - '·· -- i -SM --- / 20--- -- }i .• - grades to gravelly -SM '----:.-,:. 25--::: --- grades to with slit, moist -SP -. = <:>IVI .. ··:=···. - . 30.5 410.5 _ ... 30- ·. SAND, with gravel, trace to with stt( ·--- gray-brown, very dense, moist . ... :::::: - ~ 32.5 408.5 •: -·=·. -Continued Next Paue The stratification lines represent the approximate boundary lines between soil and rock types: In-situ, lhe transition may be gradual. WATER LEVEL OBSERVATIONS, ft ffllzzA.:lrerracon WL WL 21905 64th Avenue Wesl, Ste. 100 'i--------- : ------1: -. ·-Mounllake Terrace, WA 98043 WL V: (425) 771-3304 F: (425) 771-3549 SAMPLES TESTS -~ ~ ,: '$ "' °' ,-.: t:: °' w -di w > ';~ z "' w 0 ~Si :, :;; ~ frl 1--0 >-:, (}_...J ~8 °' 'tl z °' "'"' 0 Q. S-1 SPl 17 16 S-2 SPl --88 -6 ~ GS ---- S-3 SPl 50/5" 9 S-4 SPl 50/3" S-5 SPl 50/4" -··-__J --------· ··- S-6 SPl 50/3" _J BORING STARTED 10-14-08 BORING COMPLETED 10-14-08 RIG TRUCK\CO. EDI -~ LOGGED RMS! JOB# 81085801 LOG OF BORING NO. B-5 Paae 2 of2 CLIENT HDR Engineering, Inc. SITE Highlands Site PROJECT City of Renton Renton, Washlnaton Water Distribution Svstem Storage Study SAMPLES TESTS WELL DESCRIPTION DETAIL _, .5 <!) g .... ~ g :. i " 0:: ti g " >-0:: w t: I :r' Cl) w 6 ':~ z 0. Ii Cl) a, UJ ~~ :, ~ 0 :. a. 0 li:9 >-w Cl) ::, t w s:8 !fR <!) 0 ::, z 0:: "'"' ---~ ------SP :, t:: .... · -SP S-7 50/3" 8 ' ::.J~ :< --~-· •• 1--• -.. ·.·t:: _ _. 35 -· .. :t:: ·. -,·:t:: .· - ~-· . ,I--.. -_.·.t=--- ·.-·-t:: . .. -SP S-8 SP 50/5" 't::-· -·· ·'--·. 39.5 401.5 .. ·. t=:·-· -- Boring completed at 39.5 feet on 10/14108. No groundwater observed while drilling. No groundwater observed in piezometer on 10/23108. ' The stratiflcalion lines represent the approximate boundary lines between soil and rock types: in-situ, the transition may be gradual. WATER LEVEL OBSERVATIONS, ft llizzA.:Jrerracon BORING STARTED 10-14-08 WL 'l--1-l ---.. BORING COMPLETED 10-14-08 WL 7. _L __ 21905 64th Avenue West, Ste. 100 RIG TRUCK_,_co. -----EDI Mounllake Terrace, WA 98043 --- WL V: (425) 771-3304 F: (425) 771-3549 LOGGED RMS JOB# 81085801 LOG OF BORING NO. 8-6 Page 1 of 2 1----~--------" CLIENT HOR Engineering, Inc. ----SITE ----Highlands Site PROJECT City of Renton Renton, Washlnaton Water Distribution System Storage Study ---SAMPLES ___ TESTS (!) ...J .S 0 ~ ~ 0 DESCRIPTION al ,_- ...J :;; .; ,.: 0 .; 0:: t: >-0:: w -ffi~ :i: ~ (/) w 6 ';'~ 2 Q. (/) Ol w :::, ~ 0 :;; (>_ 0 1-0 ~2 >- Approx. Surface Elev.: 437 ft w (/) :::, ~ w Q. ...J s:8 ls]. (!) 0 :::, 2 0:: (/) al Grass over 2 Inches Topsoil over SIL TY - SAND, trace gravel, brown, very loose to --loose, damp - -SM S-1 SPl 3 11 ·; 5 432 5-SIL TY SAND, trace gravel, gray-brown, - dense, damp to moisl -- -= SM S-2 SPl 44 :_:·:'-.:- c.'-10-::: -------· -8 grades to very dense -SM S-3 si>1 50/4" ---·>---- -- 1:- 15-= - :_::\.: ... - :1: -SM S-4 ISP 50/.5" 6 GS :r ,>---- -- ·-k - 20--- .-- - :·:l··r.-: grades to with gravel -SM S-5 i,P 50/6" 8 ,~ - 25 412 25-</ SAND, with gravel, trace to with silt, -gray-brown, very dense, moist -/( - :.-. -SP S-6 SP 50/5" - - . -.. •·. 30-_·.-: - - .· : :: - 32.5 404.5 -= - Continued Next Paae The stratification lines represent the approximate boundary lines between soil and rock types: in.situ, the transition may be gradual. WATER LEVEL OBSERVATIONS, ft ilzzA.:Jrerracon BORING STARTED 10-14-08 wi-~ ----· 1:r. BORING COMPLETED 10-14-08 WL 'l Ile 21905 64th Avenue West, Ste. 100 RIG T_~UC~CO. EDI Mountlake Terrace, WA 98043 __ ,. WL V: (425) 771-3304 F: (425) 771-3549 LOGGED RMS JOB# 81085801 LOG OF BORING NO. B-6 Page 2 of 2 ----CLIENT HDR Enalneerlna, Inc. -~~ SITE Highlands Site PROJECT City of Renton Renton, Washington Water Dlstrl butlon System Storage Study SAMPLES TESTS (!) ..J -~ 0 ~ 0 DESCRIPTION Ol Iii * ..J ~ ¢! ,-: 0 ¢! 0:: ~ ffi~ t: 'i: :,: UJ ';'~ z ~ ti: (/) m UJ ::, 0 :; ~ 0 t;:g f--Z >-w (/) ::, w ~8 0::'tl (!) 0 ::, z "' U)!D 0 0. --------- SP S-7 r,p 50/6" 6 </ -,~---/ - 35-.· - '. - ··.c --... / -SP S-8 SPl 50/5" "\_-::-. 39 398 Boring completed at 39 feet on 10/14/06. No groundwater observed while drilling. The stratification lines represent the approximate boundary lines between soil and rock types: In-situ, the transition may be gradual. WATER LEVEL OBSERVATIONS, ft EzzA.:Jrerracon BORING STARTED 10-14-08 WL '5l. j!- -~ BORING COMPLETED 10-14-08 WL '!I-11' ~-- TRUCKjco. 21905 64th Avenue West, Ste. 100 RIG EDI WL --Mountlake Terrace, WA 98043 RMS jJOB# V: (425) 771-3304 F: (425) 771-3549 LOGGED 81085801 LOG OF BORING NO. B-7 Paae 1 of 2 ---------------------------,-----------------'--='"-"--'-'-'-=-f CLIENT 1------____c_H:.:DccR_.:_-cEccnsc:gin:.:e:..:eccri"'n""-g,"-ln:.:c:_:_. _______ +--___________________________________ ____. Mt. Olivet Site PROJECT City of Renton SITE Renton, Washinaton Water Distribution System Storage Study SAMPLES TESTS (!) Q -~ ~ 0 = * .-, DESCRIPTION :; ~ · 0 <: >-O'. W <' O'.~ ~ 'i: ~ ~ llJ w 6 ';°3£ ~ :, ~ w ~ ~ a. ~ b:9 ~o oc 0 >-'n h'(!)~'-'A,,_PcPr:..:o~x"'. S=c:::urf7'a:::c'se:-'E=l-=-ev.:c·~: ;-;1ca6si4c::-f'ct --c;:--:----------_ci__+-:,---l-z---f-'~---l-oc-+_rn_ai_f-~~o-+-li-+--+--------1 1:_:;0 . .-,:.: 2" Ashpalt over SAND, trace silt and - : ·-::-.>._ gravel, brown, medium dense, moist : \ 11 r :. \_. .--: SILTY GRAVELLY SAND, gray and brown, dense, moist 153 10- - - - : SM S-3SP1 15- - - - 12 9 32 38 5 -: .-._. grades to very dense -ic S-4 SP 5012" '---· No ---+-----+-+--J------+---+-~ Recovery .- ·.-_ ... ·: .-.·_. grades to wet 20-- - - - -SM S-5 SPl 5013" 11 --+--+-----+-+---l------+---+----- - 25-= - ~ ····:·· - - -SM S-6 3PT 50/6" ~---3=0~--===---------------~13'-"-14 30 -g SAND, with silt to silly, brown, dense, wet -°' to saturated - ; 2 32.5 131.5 -= ~ Continued Next Paae ~1--------...;;..;;.;.;.:;.:..:..::;:;;:.;=:.:..:.==-------....1 ......... ---._....L _ _. _ _.1,_ ..... _ _. ___ ... ~ :=~!t!~t~~if~~~ 1:~~~ ;;:~=~~~~~~~. ~~~r~:i:~~~nb~~nyd~i ~~~~~al. ~ ,___w_A~T-ER_LE_V_E_L_O_B_S_ER=V_A_T_IO_N __ s_. _fl_~m"lj ZZA .:Jf erracon I--B_O_R_IN_G_ST_A_R_T_E_D ____ 1 o_-_15_-0_8-1 ~ WL '¥-29.0 WD IY BORING COMPLETED 10-15~08 ~ WWLL r-------ifl'cc--------< 21905 64th Avenue West. Ste. 100 RIG TRUCK j co. 810858EOD11 N V: (~~in1:~~3Jiz·r,:~ ~~~~1549 LOGGED RMS I JOB# LOG OF BORING NO. B-7 Paae 2 of 2 CLIENT HDR Englneerlna, Inc. -----~--------Mt: 011vet Site PROJECT City of Renton Renton, Washington -·· Water Distribution System Storaae Studv SAMPLES TESTS (!) .J .S 0 * ~ 0 DESCRIPTION a, ii .J :. ¢i ,-: 0 ¢i >-"' ~ "'~ t: i' :,: "' w ';~ z Cl. li: "' "' w l:'!z ::, ~ 0 :. Q. 0 f-0 >-w "' ::, ~ w Cl. .J ~8 ~8. 0 a ::, z "' "'"' ·- lit 34 SP S-7 SPl 31 24 - 130 -SM Boring completed at 34 feet on 10/15/08. Groundwater observed at 29 feet while drilling. -The stratification lines represent the approximate boundary lines between soil and rock types: in-situ, the transition may be gradual. WATER LEVEL OBSERVATIONS, ft ISZZA-=lrerracon BORING STARTED 10-15-08 WL 'fl-29.0 wDl-l-BORING COMPLETED 10-15-08 "!1. 11: ~----TRUCK I co. WL 21905 64th Avenue West, Ste. 100 RIG EDI WL Mountlake Terrace, WA 98043 RMS IJOB# 81085801 V: (425) 771-3304 F: (425) 771-3549 LOGGED LOG OF BORING NO. 8-8 Page 1 of 2 1----------·-----·------------~-------·----------- CLIENT 1---------'H'.'.'D"C'R.....,E ... n ... gl'""n:::ee::.:r.::ln.:<l!.g, .:.:ln:::c.:... ------+c=-=-=-c:===----------___ _ __ ---··-------1 SITE Mt. Olivet Site PROJECT City of Renton 1---_____ ....:..:R=.en:.:.t:.::o.:.:n'-, W=a.::.sh:.:.lccn=a·to:.:.n"------_ .-. Water Distribution System Storage Study SAMPLES TESTS 13 ~ g z 0 G DESCRIPTION g ~ Well ID= APQ-799 ~ ~i~~~?;E DIA G GROUND SURFACE ELEV.: Grass over 2 Inches Topsoil over SIL TY __ SAND, trace gravel, brown, loose to medium dense, damp 1;. .. '++'+5"----s-A-N=D-.-w-it_h_g_r-av_e_l_, t_ra_c_e_s-il-1,-b-,o-w·-n-, ----·· ... :.:: medium dense, damp to moist > .·.··t ; .. .> 1' ....... 12.8 :•·· . F· . ·. 16 ·•· .... : •. J:: ·.1:.·. .J.: SIL TY SAND, with gravel, brown, medium dense, damp SILTY SAND, with gravel, gray-brown, very dense, moist grades to dense grades to very dense, wet to saturated I ~ ·.·. ·:.· & '. ·> ~ "' ,; 32.6 6 In 1 in 156ft -·-.151 143.2 140 WELL DETAIL l'. \:'=::: ·=:.· I ·=···. 123.4 ·, -:· ---- -SM S-1 5Pl - =:. SP S-2 5PT 18 4 10--= ---- -SM S-3SP1 25 9 --+--t--t-+--1--------15--- - -SM S-4SPT 53 - - 20----- ~ SM S-5SP1 45 10 - - 25 ---- -SM S-65PT 55-·- - - 30·----- !:: z ::, >-158. GS :ii Continued Next Paae 8 1-T-he-'-st-,a-tifi-,c-a-lio_n_li_ne_s_re_p..;re..;s.e·n1·1h·e..;a.,;p..;pr,.o·xi..;m.al..;e;;,b.;ou_n_d-ary-lln_e_s __ ...1,, __ .i.._...1,, _ _.__._...__.._ _ _._ _ _.,_ ..... ___ -I ~ between soil and rock types: In-situ, the lransilion may be gradual. ~ WATER LEVEL OBSERVATIONS, ft i WL '¥-33.0 WD I!: 28.0 10-23-08 ~ Wl '!. 1¥ ~ Wl • ,r: BORING STARTED 10-15-08 •• · · ZZA-11erracon1--B-o-R1-NG-co_M_P_LE-T-ED ___ 10_-1_5_-os ... 21905 64th Avenue West, Ste. 100 Mountlake Terrace, WA 98043 V: (425) 771-3304 F: (425) 771-3549 RIG ·-··rnucK\co. ·-----EDI LOGGED RMS I JOB# 81085801 LOG OF BORING NO. 8-8 Page 2 of2 CLIENT HOR Englneerlna, Inc. SITE Mt. Olivet Site PROJECT City of Renton Renton, Washington Water Distribution System Storage Studv SAMPLES TESTS WELL (!) DESCRIPTION DETAIL ...J .s 0 ~ 0 a, >-' ';f. _J ~ "' ,.: 0 "' 0:: !: 0:: ~ z x r "' w 2;~ o::w z Q. li: "' a, w WI-:::, & 0 :. Q. 0 li:9 1-Z )-w (J) :::, t w ~8 0::1) (!) Cl :::, z 0:: v, ID Cl Q. '.Ill SAND, wilh silt to silty, grayivery dense, ¥ ~· -SP S-7 SPl 56 22 ·>: :· 34 saturated , ...... 122 -SM Boring completed at 34 feet on 10115/08. Groundwater observed at 33 feet while drilling. Groundwater observed at 28 feet on 10/23/08. The stratification lines represent the approximate boundary lines between soil and rock types: in-situ, the transilion may be gradual. WATER LEVEL OBSERVATIONS, ft •zzA.:Jrerracon BORING STARTED 10-15-08 WL "l. 33.0 WD JJ: 28.0 10-23-08 BORING COMPLETED 10-15-08 WC-y--. -· Jl'. TRUCK I co. 21905 64th Avenue West, Sia. 100 RIG EDI .. Mountlake Terrace, WA 98043 RMSJJOB # ---~- WL V: (425) 771-3304 F: (425) 771-3549 LOGGED 81085801 LOG OF BORING NO. B-9 P~e__1 of±_ CLIENT HDR Engineering, Inc. SITE Mt. Olivet Site PROJECT City of Renton Renton, Washlnaton Water Distribution System Storage Study --·- SAMPLES TESTS (9 5 .S ~ 3 g DESCRIPTION "' ,.: 0 "' :;; 0:: "' ,-: I:: ,.. 0:: ~ o::il'i 'i: I rn w ':'~ z a. f--rn "' w 0 Wr :::, ~ a. 0 :;;; a. (.) f--0 ~z ,.. Approx. Surface Elev.: 153 ft w rn :::, r: w a. ..J s8 O:'t; (9 0 :, z -O'. rn"' Oo. -- j{> Grass over 1 inch Topsoil over SAND, - trace gravel and silt, brown-gray, medium --dense, moist - -SP in sP'i ~- !:}'. 16 4 - 5- ·- / -- -SP S-2 SPl 19 6 GS - / - 10-- - a; -- grades to with silt -SP S-3 SPl 23 9 =-2M -- > -15- << ------ / grades to trace silt SP S-4 SPl 26 -- -f-------20- >\ -- - --------- -SP S-5 SPl 26 12 ·.·, < - 25- -: - ···-:: - '<( - grades to with gravel SP S-6 SPT 20 - ·--30- Th ~1 _ __m_ - SIL TY SAND, trace gravel, brown, - 32.5 medium dense, wet 120.5 --Continued Next Paae The stratification lines represent the approximate boundary l!nes between soil and rock types: in-situ. the trnnsitlon may be gradual. WATER LEVEL OBSERVATIONS, fl &zzA.:lrerracon BORING STARTED 10_-15-08 -··-·· WL 'l j~-BORING COMPLETED 10-15-08 WL )! ----- TRUCK I co. ' 21905 64th Avenue West, Ste. 100 RIG EDI I----------Mountlake Terrace, WA 98043 RMS JJOB# WL V: (425) 771-3304 F: (425) 771-3549 LOGGED 81085801 LOG OF BORING NO. B-9 Paae 2 of 2 -•·" CLIENT HDR Engineering, Inc. ---------· --- SITE Mt. Ollvet Site PROJECT City of Renton Renton, Washlnaton Water Distribution System Storaae Studv SAMPLES TESTS Cl ..J .5 0 * ~ 0 DESCRIPTION "' ~ ..J ::;; ¢' ,-.; t: u ¢' >-a: ~ a:z :i: ~ (/) w ';'~ z a. (/) "' il:' ~~ ::, ~ u ::;; u li:S >-w (/) ::, ~ w ~8 g;'ll_ Cl 0 ::, z a: "'"' fl ----------- -SM S-7 SPl 23 17 34 11!! Boring completed at 34 feet on 10/15/08. No groundwater observed while drilling. The stratificalion lines represent the approximate boundary lines between soil and rock types: in.situ, the transition may be gradual. WATER LEVEL OBSERVATIONS, ft iliZZA-=lferracon BORING STARTED 10-15-08 WL 'Sl. I-'" -- BORING COMPLETED 10-15-08 WL "!. 11'. 21905 64th Avenue West, Sle. 100 RIG TRUCK I co. EDI Mountlake Terrace, WA 98043 WL V: (425) 771-3304 F: (425) 771-3549 LOGGED RMSJJOB# 81085801 APPENDIXB LABO RA TORY TESTING PROCEDURES AND RESULTS APPENDIXB LABORATORY TESTING PROCEDURES AND RESULTS A series of laboratory tests were performed during the course of this study to evaluate the index and geolechnical engineering properties of the subsurface soils. Descriptions of the types of tests performed are given below. Visual Classification Samples recovered from the exploration locations were visually classified in the field during the exploration program. Representative portions of the samples were carefully packaged in moisture tight containers and transported to our laboratory where the field classifications were verified or modified as required. Visual classification was generally done in accordance with the Unified Soil Classification System. Visual soil classification includes evaluation of color, relative moisture content, soil type based upon grain size, and accessory soil types included in the sample. Soil classifications are presented on the exploration logs in Appendix A. Moisture Content Detcm1inations Moisture content determinations were performed on representative samples obtained from the exploration in order to aid in identification and correlation of soil types. The determinations were made in general accordance with the test procedures described in ASTM: D-2216. The results are shown on the exploration logs in Appendix A. G1·ain Size Analyses A grain size analysis indicates the range in diameter of soil particles included in a particular sample. Grain size analyses were performed on representative samples in general accordance with ASTM: D-2487. The results of the grain size determinations for the samples were used in classification of the soils, and are presented in this appendix. GRAIN SIZE ANALYSIS Test Results Summary SIZE OF OPENING IN INCHES 10 0 9 !r 8 C) 0 0 - - iii 3: 7 - 0 ~ - ffi 80 z ii: - !z 50 w -(.) ffi 40 0. - 30 - 20 - 10 - ,.. 0 1000.000 12· .. ,. 11/2" I I . 100.000 U.S. STANDARD SIEVE SIZE ,,,. 316" 4 10 ,. 40 r 1"40 200 I \I , .. , " "'- ~ ,, r\ \ \ ·- 10.000 1.000 0.100 PARTICLE SIZE IN MILLIMETERS coarse Fine· Coarse Medium Fine BOULDERS COBBLES GRAVEL SAND Exploration Sample Depth (feet) Moisture(%) B-2 S-3 12.5-13 6 JOB NO: 81085801 ~ ZZA-lrerracon DATE OF TESTING: 10/27/2008 Geotechnlcal and Environmental ConsulUng ASTM D422 HYDROMETER 0.010 0.001 Silt Clay FINE GRAINED Fines(%) 30.7 Description silty SAND with gravel PROJECT NAME: Water Distribution Storage Study GRAIN SIZE ANALYSIS TestResultsSummary ASTM 0422 SIZE OF OPENING IN INCHES U.S. STANDARD. SIEVE SIZE HYDROMETER ,.. 12· r , .. 1112· 314• 3/8" ' IO 20 40 °I 11° 200 0 10 - 9 0 1-::c 8 C) jjj 0 - 3: 7 0 iii ffi 6 - 0 z Li: - !z 5 0-1 w (J ffi 40 11. - 30 - 20 - -I 10 0 1000.000 I I I I 100.000 'l 1~1 I 1 ! I '"r,, " ~ I ~ I\ ~ ' I\ \ ' I ! I 10.000 1.000 0.100 PARTICLE SIZE IN MILLIMETERS Coa!"$e Fine Coarsi:, Medium Fine BOULDERS COBBLES GRA.VEL SAND Exploration Sample Depth (feet) Moisture(%) B-4 S-3 12.5-13 7 JOB NO: 81085801 ~ ZZA-llerracon DATE OF TESTING: 10/27/2008 Geotechnlcat and EnVironmental COJ'lsulting i I I 0.010 0.001 Slit Cla:,i FINE GRAINED Fines(%) 32.7 Description silty SANO, trace gravel PROJECT NAME: Water Distribution Storage Study GRAIN SIZE ANALYSIS Test Results summary SIZE OF OPENING IN INCHES U.S. STANDARD SIEVE SIZE 10 36" 12" .. 3" 11'12·_ 314" ,,.. ' 10 20 •• i 1<10 200 0 I -~~ 0 r -~, 0 ~ -I"- 9 0 ~ -I) 0 ,v-------·-\ - 0-1 ' I\ 0 \ - 3 0 - 2 0 - 0 I - 0 1000.000 100.000 10.000 1.000 0.100 PARTICLE SIZE IN MILLIMETERS Coar&& Fine Coarse Medium Fine BOULDERS COBBLES GRAVEL SAND Exploration Sample Depth (feet) Moisture(%) B-5 $-2 7.5-9 6 ~ ZZA-1rerracon JOB NO: 81085801 DATE OF 10/27/2008 Geotechnlcal and l:nvl,onmental Consulting TESTING: ASTM 0422 HYDROMETER I ------ ~- 0.010 0.001 sm Clay FINE GRAINED Fines(%) 31.8 Description silty SAND with gravel PROJECT NAME: Water Distribution Storage Study GRAIN SIZE ANALYSIS Test Results Summary SIZE OF OPENING IN INCHES 100 - 0 0 9 1- :i:: 8 C) jjj ;: 7 - 0 ~ ffi 6 - 0 z u: - !z 50 w (..) - ffi 40 D.. - 30 - 20 .. 10 - 36" 0 1000.000 12·· .. ,. 1112' I -----· 100.000 Coarse U.S. STANDARD SIEVE SIZE 314" 3'3" ' 10 20 " i 140 200 \ I \ \ I ~ ' i\ " '\I ·-- \ 1,[\ ... ~ 10.000 1.000 0.100 PARTICLE SIZE IN MILLIMETERS Fine Coarse Medium Fine BOULDERS COBBLES GRAVEL SAND ASTM 0422 HYDROMETER I ... 0.010 0.001 Silt Clay FINE GRAINED Comments: Sample did not meet minimum mass requirements based on maximum particle size, per ASTM D 422. Exploration Sample Depth (feet) Moisture(%) Fines(%) Description B-6 S-4 17.5-18 6 11.4 sandy GRAVEL with slit JOB NO: 81085801 PROJECT NAME: ~ ZZA-lrerracon DATE OF 10/27/2008 Water Distribution Storage Geotechnlcal and Envlronmental Consurting TESTING: Study GRAIN SIZE ANAL YSJS Test Results Summary SIZE OF OPENING IN INCHES 36" 10 0 - 9 0 I - 0 - 0 - 0 - 0 - 0 - 30 - 20 - 10 - 0 1000.000 12" .. a· 1112· I I I 100.000 U.S. STANDARD SIEVE SIZE 314" 3111" 4 10 20 40 i 1,40 200 -~ I ~" \ \ ---... -.--- ~ \ ~--·- I I ~I 10.000 1.000 0.100 PARTICLE SIZE IN MILLIMETERS Coarse Fine Coarse Medium Fine BOULDERS COBBLES GRAVEL SAND Exploration Sample Depth (feet) Moisture(%) B-8 S-2 7.5-9 4 JOB NO: 81085801 ~ ZZA-lrerracon DATE OF 10/27/2008 Geotechnlcal and Environmental Consultlng TESTING: ASTM 0422 HYDROMETER I I 0.010 0.001 Silt Clay FINE GRAINED Fines(%) 4.6 Description SAND, trace gravel and silt PROJECT NAME: Water Distribution Storage Study GRAIN SIZE ANALYSIS Test Results Summary ASTM D422 SIZE OF OPf.NING IN INCHES U.S. STANDARD SIEVE SIZE HYDROMETER ,,. .. 3• 1112· 314" 318" 10 I i ! i j I :>O ''l 6 1 0 100 ..,.J,.,.,I -.-,-f-..-J.__,....,1.1...,...,....,.ll --i "'--,i,..,.,..i..11 ............-1-..,i...,.,..I ,..,__,__..J.,....,l,..,~~~ 9/ : I i ltk ~--, : I [ : , 1i0 r~ ,!111 i I ! i . !1 I I ' ' I--i I' I I I .. rs-, I ! i I :c 80 >· I Ii '\: Cl I·' I w -I I ii I : I I l 3: 70 ·HH++-t-+--+---+tt+l-+-+-+-+ j i-; ; I ~ -i11. r i I I I 11 I ffi 60 ~ _ I i I 111 I 1 11! 1r I I: !z 50 r+-+-+-+--+H++-l-1-j ·-: !:J w -I 1·.· Ii 1. \ ·t-i , , I !: U I 1 1: i J1 I !1 -it ~~-1 I 30 111 -:: 11, 'I I I i i \ 'I I! I I ! ~-\1----++++++ 20 I' i I I ! 104-t+++t+-I- - -- ! I : ~----I ···- ! ~ 1-- i -·· I I -· ·- ' t ~ I i I I I I I I -. ~ i , 1 i i I O~.LLLL.L_.L_-j.LLLLL!....J.._.__-+.LJ.LLLL.L_.L_--!J.!.!..U...L..L-1._...µJW..LL_J_..l__f'.ll..LL.L.J.- 1000.000 100.000 10.000 1.000 0.100 0.010 0.001 PARTICLE SIZE IN MILLIMETERS Coarse Fini, Coarse Medium Fina S11 Clay BOULDERS COBBLES GRAVEL SAND FINE GRAINED I._____~~... __ J Exploralion B-9 Sam!°l~---+-D_e.,_pt_h...:(c..fe_e.:..t)_I--M_o_is_tu __ re'-"-(%..:.•)-1-_Fi_ne_s...c(c..%.:..)-1._D_e_s_cr..:ip_ti_on_--l S-2 7.5-9 6 6.4 SAND with silt and gravel JOB NO: 81085801 PROJECT NAME: ~ ZZA-lrerracon DATE OF 10127/2008 Water Distribution Storage Geotechnical and Environmental Consulting TESTING: Study ·- HIGHLANDS 435 PRESSURE ZONE RESERVOIRS Prepared for: 10555 Grady Way 5th Floor Renton, WA 98055 REN 113.104.01.104 Prepared by: RH2 ENGINEERING, INC. November 2015 CITY OF RENTON HIGHLANDS 435 PRESSURE ZONE RESERVOIRS TECHNICAL INFORMATION REPORT NOVEMBER 2015 Prepared by: RH2 Engineering, Inc. Prepared for: the City of Renton Note: 1bis Technical Information Report was completed under the direct supervision of the following Licensed Professional Engineers registered in the State of Washington. Date Signed: 11/12/15 Date Signed: 11/12/15 2/17/2014 5,26 PM Z: \Bothell\Data \REN\ 113-104\04 Smnnwater Report\ TIR\ TIR Title Page.docx City of Renton Highlands 435 Pressure Zone Reservoirs Project TIR Table of Contents Section 1 -Project Overview ..................................................................................................... 1 General ....................................................................................................................................................... 1 Section 2 -Conditions and Requirements Summary ............................................................... 1 Core Requirement No. 1 -Discharge at the Natural Location ......................................................... 2 Core Requirement No. 2 -Off-site Analysis ........................................................................................ 2 Core Requirement No. 3 -Flow Control ............................................................................................. 2 Core Requirement No. 4-Conveyance System .................................................................................. 2 Core Requirement No. 5 -Erosion and Sediment Control.. ............................................................. 2 Core Requirement No. 6 -Operation and Maintenance .................................................................... 3 Core Requirement No. 7 -Financial Guarantees and Liability ......................................................... 3 Core Requirement No. 8-Water Quality ............................................................................................ 3 Special Requirement No. 1 -Other Adopted Area-Specific Requirements ................................... .4 Special Requirement No. 2 -Flood Hazard Area Delineation ......................................................... .4 Special Requirement No. 3 -Flood Protection Facilities .................................................................. .4 Special Requirement No. 4 -Source Controls ..................................................................................... 5 Special Requirement No. 5 -Oil Control.. ........................................................................................... 5 Special Requirement No. 6 -Aquifer Protection Area ....................................................................... 5 Section 3 -Off-site Analysis ...................................................................................................... 5 Task 1 -Study Area Definition and Maps ............................................................................................ 5 Task 2 -Resource Review ....................................................................................................................... 5 Task 3 -Field Inspection ........................................................................................................................ 6 Task 4-Drainage System Description and Problem Descriptions .................................................. 6 Task 5 -Mitigation of Existing or Potential Problems ....................................................................... 7 Section 4 -Flow Control and Water Quality Analysis and Design ........................................... 7 Johns Creek Basin IDA Existing Site Hydrology (Part A) ................................................................ 7 Johns Creek Basin IDA Developed Site Hydrology (Part B) ............................................................ 8 Honey Creek Basin IDA Developed Site Hydrology (Part B) .......................................................... 9 Johns Creek Basin IDA Performance Standards (Part C) ............................................................... 11 Honey Creek IDA Performance Standards (Part C) ........................................................................ 11 Johns Creek Basin IDA Flow Control System (Part D) .................................................................. 11 Honey Creek Basin IDA Flow Control System (Part D) ................................................................ 12 Water Quality System (Part E) .............................................................................................................. 13 Section 5 -Conveyance System Analysis and Design ............................................................ 13 Section 6 -Special Reports and Studies .................................................................................. 14 Section 7 -Other Pennits ........................................................................................................ 14 Section 8 -CSWPPP Analysis and Design ............................................................................. 15 ESC Plan Analysis and Design (Part A) .............................................................................................. 15 Stormwater Pollution Prevention and Spill (SWPPS) Plan (Part B) ................................................ 18 11/12/2015 11,46 AM \ \t:h.2\dfs\Bothcll\Data.\REN\113-104\04 StortnW3t.cr Rcpott\TIR\TIR 435 PZ Project 2015_11-lt .doa: City of Renton Technical Information Report November 2015 Highlands 435 Pressure Zone Reservoirs Section 9 -Bond Quantities, Facility Summaries and Declaration of Covenant ................... 24 Section 10 -Operations and Maintenance Manual ................................................................ 24 APPENDICES Appendix A -Worksheet and Forms Appendix B -Geo Report Appendix C -Threshold Discharge Areas Appendix D -Salmon Habitat Projects WRIA 8 Appendix E -Downstream Analysis Appendix F -Resource Review Appendix G -Flow Control BMPs Appendix H -KCRTS Modeling Appendix I -Existing and Proposed Conveyance Systems Backwater Analyses (To be provided at Utility Construction Permit submittal) Appendix J -CSWPPP Sample Forms (To be provided at Utility Construction Permit submittal) Appendix K -Stormwater Pollution Prevention and Spill Plan BMPs (To be provided at Utility Construction Permit submittal) Appendix L -Operations and Maintenance Manual (To be provided at Utility Construction Permit submittal) ii 11/12/201511'46 AM \ \rh2\dfs\Both.cll\Data\REN\Il3-104\04 Stonnwatct Rcport\TIR\TIR435 PZ Project 2015_11-11 .doa SECTION 1 -PROJECT OVERVIEW GENERAL The City of Renton (City) owns and operates a potable water reservoir site in a residential area off Northeast 12"' Street between Monroe Avenue Northeast and Pierce Place Northeast. The City desires to redevelop the site to remove the existing reservoirs and appurtenant structures that have reached the end of their useful life, and reconstruct new potable water reservoirs and appurtenant structutes that will maximize the usability of the site for potable water storage and renew the useful life of the facilities. It is expected that the improvements at the project site will be constructed in phases over many years. This Technical Information Report (TIR) addtesses construction of the phase 1 reservoir and includes planning-level information for future stormwater system expansion for phase 2. The project site is on a lot commonly known by the City as 3410 Northeast 12"' Street, Renton, Washington. The parcel number is 0423059186. The area of the site is approximately 4. 7 acres. Currently, only the southern half of the site has been developed with potable water reservoirs and associated water infrastructute. Under phase 1 of the proposed project, the northern half of the site will be developed to construct a new 6.3-million-gallon reservoir. The site has two Threshold Discharge Areas (TDAs). A TIR worksheet has been prepared for each of the two TD As for this project (Figures ta and 1b in Appendix A). A Vicinity Map showing the proposed site is included in Appendix A as Figure 2. The site is at a localized highpoint, therefore, the upstream tributary area to the project site is negligible. A Soil Survey Map from the Natural Resources Conservation Service has been included as Figure 4 of Appendix A and indicates that on-site soils are Alderwood gravelly sandy loam, which is classified as Hydrologic Soil Group (HSG) 'C.' In addition, ZZA Terracon prepared a Geotechnical Report, dated January 19, 2009, which provides additional and site-specific information regarding the on-site soils (Appendix 8). This TIR is intended to demonstrate compliance with the City ef &nton Amendments to the King County Surface Water Design Manual, February 2010 Edition, and the applicable sections of the King County S urfoce Water Design Manual, 2009 Edition, (hereinafter collectively referred to as the RKCSWDM) for the proposed project. Since the project will be constructed in phases over many years, this TIR will demonstrate compliance for the current proposed project improvements for phase 1. If additional or alternative stormwater management standards are implemented at a futute date after preparation of this TIR, and they will affect the results of this TIR, it can be amended at such time to ensure compliance with the City of Renton standards. SECTION 2 -CONDITIONS AND REQUIREMENTS SUMMARY In reviewing RKCSWDM Section 1.1.2 -Drainage Review Types and Requirements, and Figure 1.1.2.A -Flow Chart for Determining Type of Drainage Review Required, the following criteria have been considered: The project is not a single-family residence. The project is a redevelopment that proposes to add or replace more than 2,000 square feet (sf) of impervious surface. 11/12/2015 11,46 AM: 2015_11-lt .doa \\rh2\dfs\Bothc:ll\Dau.\REN\113-104\04 Stonnw= Rcpon\TIR\TIR 435 PZ Project City of Renton Technical Information Report November 2015 Highlands 435 Pressure Zone Reservoirs • The project will not result in 50 acres or more of new impervious surface. Based on this rationale, the project will be subject to Full Drainage Review. CORE REQUIREMENT No. 1-DISCHARGE AT THE NATURAL LOCATION The existing site has two natural discharge locations and two IDAs. Approximately 60 percent of the project site is tributary to the Johns Creek Basin and the remaining 40 percent is tributary to the Honey Creek Basin. Appendix C contains information regarding the delineation of the IDAs. The project does not propose to divert flows from either natural discharge location, nor from the IDAs. CORE REQUIREMENT No. 2-OFF-SITE ANALYSIS An in-depth off-site analysis was performed for the project site and is detailed in Section 3 of this TIR. CORE REQUIREMENT No. 3 -FLOW CONTROL The project site is tributary to two drainage basins. The project is not exempt from Core Requirement No. 3. In accordance with the RKCSWDM Flow Control Map, Reference 11a, the area of the project site that is tributary to the Johns Creek Basin is subject to the Peak Rate Flow Control Standard -Matching Existing, and the area of the project site that is tributary to the Honey Creek Basin is subject to Flow Control Duration Standard-Matching Forested. In the Johns Creek Basin, phase 1 of the project proposes to: • Add 0.89 acres of new impervious surface; and • Add or replace 0.16 acres oflandscaped or lawn area. In reviewing the requirements of RKCSWDM Section 1.2.3.1.A -Peak Rate Flow Control Areas, the 0. 76 acres of new impervious surface and 0.16 acres of landscaped/lawn area are considered Target Surfaces. In the Honey Creek Basin, the project proposes to: • Add 0.89 acres of new impervious surface; and • Add or replace 0.11 acres oflandscaped or lawn area. In reviewing the requirements of RKCSWDM Section 1.2.3.1.B -Flow Control Duration Standard Areas, the 0.89 acres of new impervious surface and the 0.11 acres of landscaped/lawn area are considered Target Surfaces. CORE REQUIREMENT NO. 4-CONVEYANCE SYSTEM The project proposes to install a conveyance system for collecting and discharging water from the project site. The proposed conveyance system will be designed to convey and contain the 25-year design storm event. The final design of the conveyance system and calculations will be prepared at the time of the Utility Construction Permit application. CORE REQUIREMENT No. 5 -EROSION AND SEDIMENT CONTROL A temporary erosion and sedimentation control (TESC) plan will be developed and included as the erosion and sedimentation control (ESC) plan of the plan set for Phase 1 of the project 2 11/12/2015 11'46 AM \ \:diZ\dfs\Bothcll\Dam\REN\l tl-104\04 StormWll.ter Reporr\TIR\ TIR 435 PZ Proiect 2015_1 H 1 .docx City of Renton Technical Information Report November 2015 Highlands 435 Pressure Zone Reservoirs at the time of the Utility Construction Permit application. Additional phases of the project will require development of site-specific ESC plans as the details of those phases are developed. A Construction Stormwater Pollution Prevention Plan is included in Section 8. CORE REQUIREMENT No. 6-OPERATION AND MAINTENANCE Section 10 includes information regarding the Operations and Maintenance (O&M) Manual. The drainage facilities are proposed to be maintained by the City. CORE REQUIREMENT No. 7 -FINANCIAL GUARANTEES AND LIABILITY In accordance with RKCSWDM Section 1.2.7 -Core Requirement No. 7 -Financial Guarantees and Liability, all persons constructing any surface water facilities are required to post with the City a bond, assignment of funds, or certified check. For this project, the City's Water Department requests that this requirement be waived, consistent with RCW 35.21.470, which states: A city or town may not require any state agency or unit of local government to secure the performance of a permit requirement with a surety bond or other financial security device, including cash or assigned account, as a condition of issuing a permit to that unit of local government for a building construction project. As used in this section, "building construction project" includes, in addition to its usual meaning, associated landscaping, street alteration, pedestrian or vehicular access alteration, or other amenities or alterations necessarily associated with the project. CORE REQUIREMENT ND. 8-WATER QUALITY In accordance with Definitions in the RKCSWDM, the proposed project does not contain pollution-generating surfaces, as described below: Refer to page 1-4 of the RKCSWDM. Pollution-generating impervious surface (PGIS) means an impervious surface considered to be a significant source of pollutants in stormwater runoff. Such surfaces include those that are subject to vehicular use2 or storage of erodible or leachable materials, wastes, or chemicals, and that receive direct rainfall or the run-on or blow-in of rainfall. Metal roofs are also considered to be PGIS unless they are treated to prevent leaching. Footnote 2 is defined as: Sub;ed to vehicular u,e means the surface, whether paved or not, is regularly-used by motor vehicles. The following surfaces are considered regularly-used by motor vehicles: roads, unvegetated road shoulders, bike lanes within or not separated from the traveled lane of a roadway, driveways, parking lots, unfenced firelanes, diesel equipment storage yards, and airport runways. The following surfaces are not considered regularly-used by motor vehicles: road shoulders primarily used for emergency parking, paved bicycle pathways, bicycle lanes adjacent to unpaved or paved road shoulders primarily used for emergency parking, fenced firelanes, and infrequently-used maintenance access roads. TIR Comment: The reservoir roofs will be constructed with concrete material that is not leachable. The paved roads on the project site are infrequently used by the City's Water Department and not regularly-used by motor vehicles. 11/12/20151"46AM \\rh2\dfs\Bothcll\Data\REN\113--104\04Stonnwitttt Rcport\TIR\TIR 435 PZ Project 2015_11-11 .docs: City of Renton Technical Information Report Refer to Page 1-4 of the RKCSWDM. November 2015 Highlands 435 Pressure Zone Reservoirs Pollution-generating pervious surface (PGPS) means a non-impervious surface considered to be a significant source of pollutants in surface and stormwater runoff. Such surfaces include those subject to use of pesticides and fertilizers, loss of soil, or the use or storage of erodible or leachable materials, wastes, or chemicals. Such surfaces include, but are not limited to, the lawn and landscaped areas of residential or commercial land uses, golf courses, parks, sports fields, and City-standard grassed modular grid pavement. TIR Comment: The City's Water Department mows the grass areas of the project site in its exiting condition and will continue to do so in the redeveloped condition. The Water Department does not propose to use pesticides and fertilizers for maintenance of grass or other pervious areas. Since the proposed project does not contain pollution-generating surfaces, water quality treatment is not required. SPECIAL REQUIREMENT No. 1-OTHER ADOPTED AREA-SPECIFIC REQUIREMENTS A Master Drainage Plan is not known to exist for the project site. A Basin Plan is not known to exist for the project site. A Salmon Habitat Plan exists for the project site and is titled, the Lake Washington/Cedar/Sammamish Watershed, also known as Water Resource Inventory Area (WRIA) 8. The project site is located specifically in the Lake Washington sub-basin ofWRIA 8.' The Salmon Habitat Plan for the Lake Washington sub-basin contains specific salmon recovery projects, although none appear to be in the vicinity of the potable water system project. Appendix D contains a map of salmon recovery projects. A Stormwater Compliance Plan is not known to exist that would affect the project site. A Flood Hazard Reduction Plan is not known to exist that would affect the project site. A Shared Facility Drainage Plan is not known to exist that would affect the project site. SPECIAL REQUIREMENT No. 2-FLDOD HAZARD AREA DELINEATION The proposed project site is not directly adjacent to a stream, lake, wetland, or closed depression, and, therefore, does not warrant delineation of the 100-year flood plain. SPECIAL REQUIREMENT No. 3-FLDOD PROTECTION FACILITIES The proposed project will not rely on an existing flood protection facility for protection against hazards posed by erosion or inundation, nor will it construct a new flood protection facility. 1 Additional information can be found online at http:/ / www .govli nk.oq! / w;it.ershcds / 8 /activi tie~-partners / <lefault.aspx#map. 4 ll/12/20151H6AM \ \rh2\d&\Botbcll\Data.\REN\113-104\04 Stomiwuer Rq,on\TIR\TIR 435 PZ Project 2015_11-1 l .doa City of Renton Technical Information Report SPECIAL REQUIREMENT No. 4-SOURCE CONTROLS November 2015 Highlands 435 Pressure Zone Reservoirs The proposed project does not require a commercial building pennit nor a commercial site development pennit; therefore, in accordance with RKCSWDM Section 1.3.4 (page 1-73), this special requirement is not applicable. SPECIAL REQUIREMENT No. 5 -OIL CONTROL The proposed project site is not considered high-use; therefore, this special requirement does not apply. SPECIAL REQUIREMENT No. 6-AQUIFER PROTECTION AREA The proposed project site lies within Aquifer Protection Area Zone 2 and the Cedar Valley Sole Source Aquifer Project Review Area, as identified on the Groundwater Protection Areas in the City map. The project does not propose to construct pollution-generating surfaces; therefore, a stormwater liner is not anticipated to be required. SECTION 3 -OFF-SITE ANALYSIS TASK 1-STUDY AREA DEFINITION AND MAPS The Downstream Analysis Map Series is included in Appendix E. Appendix E also contains maps that demarcate the downstream flow path for a distance of 1 mile. TASK 2 -RESOURCE REVIEW Basin Plan -A basin plan is not known to exist for the project site. Sensitive Areas Folio -Appendix F contains the following maps: Sensitive Slopes: There are some sensitive slopes (greater than 25-percent and less than or equal to 40-percent) on the project site and downstream of the project site. There are protected slopes (greater than 40-percent and less than or equal to 90-percent) downstream of the project site adjacent to Honey Creek. Landslide: There are slopes downstream of the project site that are at moderate risk for landslide. Honey Creek is a Class-3 stream that is downstream of the project site, and runoff from part of the site is tributary to Honey Creek. There are no mapped wetlands on the project site, but there is one mapped wetland downstream of the project site and associated with Honey Creek. There is mapped erosion associated with the banks of Honey Creek downstream of the project site. City maps do not show the site and downstream areas being in Special Flood Hazard Areas (100-year flood) nor Other Flood Areas (Zone X -500-year flood). • The project site and downstream area do not show any mapped coal-mine hazards. • The project site lies within Aquifer Protection Area Zone 2 and the Cedar Valley Sole Source Aquifer Project Review Area. 11/12/201511'46AM \\th2\dfs\Bothcll\Da.u\REN\113-104\04 Stormwata: Rcport\TIR\TIR 435 PZ Project 2015_11-11 .<loo: City of Renton Technical Information Report November 2015 Highlands 435 Pressure Zone Reservoirs Section 303d List -Appendix F contains a Washington State Department of Ecology (Ecology) map indicating that downstream of the project site for the Johns Creek Basin, Lake Washington is listed for bacteria and total phosphorus. In the Honey Creek Basin, Honey Creek is tributary to May Creek, which is listed for bacteria, dissolved oxygen, mercury, pH, and ammonia-N. TASK 3 -FIELD INSPECTION A Level-1 inspection and site visit was conducted on September 10, 2014. The temperature was 71 degrees Fahrenheit, and sunny, with 0.00 inches of precipitation. It had rained 0.05 inches 2 days earlier on September 8, 2014. The downstream conveyance system was inspected for both the Johns Creek Basin and Honey Creek Basin IDAs. Overall, no drainage issues were observed, and all drainage systems were free-flowing. Land use, impervious surfaces, topography, pipe sizes, drainage structures, and relevant critical areas were verified to the extent possible as displayed in the study area maps and other relevant figures. TASK 4-DRAINAGE SYSTEM DESCRIPTION AND PROBLEM DESCRIPTIONS The 435 Pressure Zone Reservoirs project site is divided into two IDAs. The two IDAs are shown in the map in Appendix C, and downstream flow paths are shown in Appendix E. JOHNS CREEK BASIN TDA DOWNSTREAM ALIGNMENT The Johns Creek Basin TDA discharges off the northwest comer under historic conditions. Currently, stormwater sheet flows off the site and is tributary to the downstream property (a retirement residence) where it is collected in an on-site stormwater conveyance system and underground facilities. The stormwater system routes the stormwater away from its historic flow path to the Johns Creek Basin and instead routes it east and north for discharge to Honey Creek, which would technically be a basin transfer at the time the development was constructed. See the as-built plan for the retirement residence in Appendix E, which identifies the basin transfer. For the purposes of the downstream analysis of the Johns Creek Basin IDA, the historic flow path was followed, as shown in Appendix E. There are currently no known, existing, or potential drainage systems problems reported from the City, local owners, or observed during the field inspection for the Johns Creek Basin IDA. HONEY CREEK BASIN TDA DOWNSTREAM ALIGNMENT The Honey Creek Basin IDA discharges off the northeast comer of the project site via a 10-inch concrete pipe after being collected on-site using existing catch basins and a collection system. From the northeast comer of the site, runoff travels due north in a 12-inch concrete pipe to the south edge of NE Sunset Boulevard. Runoff then travels under NE Sunset Boulevard via an 18-inch concrete pipe that discharges at a culvert outfall approximately 70 feet north of NE Sunset Boulevard. Runoff then travels in a channel in a northeasterly direction. The culvert outfall and channel show signs of minor erosion and incising for approximately 100 feet before reaching a more heavily-vegetated area (Appendix E). RH2 Engineering, Inc., (RH2) staff were not able to field-verify the remainder of the downstream data due to heavy vegetation growth and systems primarily on private properties; therefore, RH2 relied on the available data from the City's online geographic information system (GIS) mapping application. The channel is approximately 325 feet in length, from the 18-inch culvert outfall to a point where it enters a 24-inch culvert pipe that continues to flow in the northeast 11/12/20t51H6AM \ \rh2\dfs\Bothdl\Data\REN\113-104\0-4 Starnrwv.ter Report\TIR\TIR 435 PZ Project 2015_11-11 .doo City of Renton Technical Information Report November 2015 Highlands 435 Pressure Zone Reservoirs direction through a series of pipes and catch basins before outfalling to another channel approximately 80 to 90 feet from the edge of Honey Creek. Flow travels the 80 to 90 feet in a channel and then becomes tributary to Honey Creek. Honey Creek then flows in a northwesterly direction for approximately 1 mile before it becomes tributary to May Creek, which eventually discharges into Lake Washington. There are currently no known existing or potential drainage system problems reported from the City, local owners, or observed during the field inspection for the Honey Creek Basin TDA. Parcels, pipe sizes, and approximate general slopes for both downstream alignments are shown in the Off-site Analysis Drainage System Table and on project maps (Appendix E). TASK 5-MITIGATION OF EXISTING OR POTENTIAL PROBLEMS A review of the information for the project site found no potential or existing drainage or water quality problems beyond the minor erosion and incising of the outfall and channel downstream of the 18-inch concrete pipe north of NE Sunset Boulevard. With the detention standard of Flow Control Duration Standard -Matching Forested, it is anticipated that these downstream conditions will decrease erosion/incising under developed conditions. SECTION 4-FLOW CONTROL AND WATER QUALITY ANALYSIS AND DESIGN JOHNS CREEK BASIN TDA EXISTING SITE HYDROLOGY (PART A) The Existing Site Plan is included in the plan set. The site is developed with potable water reservoirs and appurtenant facilities along with gravel maintenance access roads. There are some trees on the site, as shown in the existing site plan. As previously mentioned, the site has rwo TDAs. The basins have been delineated in the maps in Appendix C. As mentioned in the Off-site Analysis Section above, the property downstream of the Highlands Reservoir site constructed a conveyance system that routes all runoff from the Highlands Reservoir site to the Honey Creek Basin, technically resulting in a basin transfer. The proposed project seeks to correct that and restore historic flow patterns. Because the site is at a localized highpoint, the upstream tributary area to the project site is negligible. Flow Control Best Management Practices (BMPs) are required for the project site per RKCSWDM Section 1.2.3.3 since the project is subject to Core Requirement No. 3. The proposed project is a non-subdivision project making improvements on an individual site/lot, therefore, implementation of Flow Control BMPs shall be in accordance with the "Individual Lot BMP Requirements" in Section 5.2.1 of the RKCSWDM. The site is more than 22,000 sf and will have more than 45 percent impervious, therefore, it is considered a Large Lot High Impervious site, and subject to RKCSWDM Section 5.2.1.2 -Large Lot High Impervious BMP Requirements. The criteria in the RKCSWDM for full dispersion was reviewed. Full dispersion was eliminated from consideration since the existing site is developed with grass and not native vegetation. In addition, it did not seem reasonable that the grassed areas could provide a sufficient hydrologic response equivalent to full dispersion. Since full dispersion is not feasible, the project's target impervious surfaces are proposed to be mitigated using low impact development techniques. The project has an impervious surface 11/12/201511'46 AM \ \rh2\dfs\Bothell\Da~\REN\113,104\04 StoIJDW:1.tcr R.cport\TIR\TIR 435 PZ Project 2-015_11-tl .doa. City of Renton Technical Information Report November 2015 Highlands 435 Pressure 2one Reservoirs coverage of more than 65 percent; therefore, flow control BMPs must be applied to an impervious area equal to at least 10 percent of the site/lot or 20 percent of the target impervious surface, whichever is less. The following paragraphs detail the target impervious surfaces and application of flow control BMPs by TDA. JOHNS CREEK BASIN TOA DEVELOPED SITE HYDROLOGY (PART 8) The existing surface conditions are approximately 50 percent grass and 50 percent trees (forested). The Flow Control Standard for the Johns Creek Basin is Peak Rate Flow Control Standard -Match Existing. The Target Surfaces per RKCSWDM Section 1.2.3.1.A are the new pervious and new impervious surfaces. Replaced impervious and replaced pervious surfaces are not target surfaces. Tables 1, and 2 summarize the surface areas for modeling in the King County Runoff Time Series (KCRTS). The "Model As ... " part of Table 1 indicates whether the surface was modeled as predeveloped (predev.tsf), developed (dev.tsf) or bypass (bypass.ts£). The table identifies small areas that bypass the storm detention facilities because of infeasibility to convey the runoff to the proposed storm detention facilities. Additionally, the modeling identifies areas of the proposed access road around the reservoir that will be retained and infiltrated slowly, as described in detail later in this section of the Report. Table 1 -Johns Creek IDA Stormwater Areas Site & Project Site to Vault/Pump Proposed Impervious to Vault Existing Impervious to Vault Existing Pervious to Vault Project Site to Bypass Area (ac) 0.72 0.48 1.02 Proposed Access Road to Infiltration 0.13 Proposed Pervious to Bypass Proposed Sidewalk to Bypass Proposed Frontage Planter Strip to Bypass 0.13 0.04 0.03 Model As ... Predev.tsf 50% TG, 50% TF IMP TG 50% TG, 50% TF TG TG Notes: TG = Till Grass, TF = Till Forest, IMP = Impervious Dev.tsf Bypass.tsf IMP IMP TG TG IMP TG Flow control BMPs must be applied to an impervious area equal to at least 10 percent of the site/lot or 20 percent of the target impervious surface, whichever is less (fable 2). The target 8 11/12/20151H6 AM \ \th2\dfu\Bothell\Dab.\REN\113--104\04 Stonnwatcr Rqxm:\TIR\TIR ,4-35 PZ Project 2015_11-11 .doa City of Renton Technical Information Report November 2015 Highlands 435 Pressure Zone Reservoirs impervious surfaces in Table 1 are the Proposed Impervious to Vault, Proposed Access Road to Infiltration, and Proposed Sidewalk to Bypass. Table 2 -Flow Control BMP Calculations Area Area (ac) Johns Creek Basin TDA in Site 3.06 Target Impervious in Johns Creek Basin TDA 0.89 20 percent of Johns Creek Basin TDA 0.612 10 percent of Target Impervious 0.09 Area for Flow Control BMPs 0.09 The project proposes to accommodate the flow control BMP standard through the use of infiltration into the soils below the access road subgrade for 0.13 acres of access road around the proposed reservoir, thereby exceeding the minimum 0.09 acres required. The BMP will act as permeable pavement but use traditional asphalt with a permeable subgrade instead. The water will be allowed to sheet flow to the edge of the roadway and collect in a gravel trench that is connected to the permeable subgrade, allowing water to infiltrate to the existing soils beneath the pavement. The Geotechnical Report prepared by ZZA-Terracon (Appendix B) indicates the soils below the topsoil are 2 to 5 feet of loose to medium density silty sand, which is then underlain by dense to very dense sand with varying amounts of silt and gravel. In reviewing the sieve analyses for Borings B-2 and B-4, which are generally the closest to the project improvements, the project D10 size (10 percent of the material passing the sieve size listed) would be 0.05 millimeters. Using guidance from Ecology's Stormwater Management Manual for Western Washington, 2012 Edition, the infiltration rate for this soil is 0. 73 inches per hour. The pavement was modeled using KCRTS and was determined that this method would indeed infiltrate all stormwater from the proposed impervious roadway. Based on the area of flow control BMPs calculations, it was determined that 0.09 acres are required to be infiltrated. This resulted in 262 linear feet of a 15-foot-wide road, constructed with the permeable subgrade for the Johns Creek Basin TDA. The areas where this road section will be used are shown on the site plan in Appendix G. The calculations and typical road sections are also found in Appendix G. The project proposes to connect any proposed roof downspouts using a perforated pipe connection. HONEY CREEK BASIN TOA DEVELOPED SITE HYDROLOGY {PART B) The Flow Control Standard for the Honey Creek Basin is Flow Control Duration Standard Matching Forested Site Conditions. The Target Surfaces per RKCSWDM Section 1.2.3.1.A are the new pervious and impervious surfaces and replaced impervious surface. Tables 4, 5, and 6 summarize the surface areas for modeling in the King County Runoff Time Series (KCRTS). 11/12/2015 11,46 AM \ \ch2\dfs\Bothcll\Dw\REN\113-l04\04 Stormw,;,.tc:r Repott\TIR\TIR.435 PZ ProJc:ct 2015_11-lt .doa City of Renton November 2015 Technical Information Report Highlands 435 Pressure Zone Reservoirs Table 3 -Honey Creek TOA Model As ... Area Stormwater Areas (ac) Predev.tsf Dev.tsf Bypass.tsf Proposed Impervious to Vault 0.76 TF IMP Existing Impervious to Vault 0.79 IMP IMP Existing Pervious to Vault 0.33 TG TG Project Site to Bypass Proposed Access Road to Infiltration 0.11 Proposed Pervious to Bypass 0.10 TF TG Proposed Sidewalk & Driveway to Bypass 0.02 TF IMP Proposed Frontage Planter Strip to Bypass 0.01 TF TG Flow control BMPs must be applied to an impervious area equal to at least 10 percent of the site/lot or 20 percent of the target impervious surface, whichever is less (fable 4). The target impervious surfaces in Table 3 are the Proposed Impervious to Vault, Proposed Access Road to Infiltration, and Proposed Sidewalk & Driveway to Bypass. Table 4 -Flow Control BMP calculations Area Area (ac) Honey Creek Basin TOA in Site 1.84 Target Impervious in Honey Creek Basin TOA 0.89 20 percent of Honey Creek TOA 0.368 10 percent of Target Impervious 0.089 Area for Flow Control BMPs 0.089 The project proposes to accommodate the flow control BMP standard through the use of infiltration into the soils below the access road subgrade for 0.11 acres of access road around the proposed reservoir, thereby exceeding the minimum 0.09 acres required. The BMP will act as permeable pavement but use traditional asphalt with a permeable subgrade instead. The water will be allowed to sheet flow to the edge of the roadway and collect in a gravel trench that is connected to the permeable subgrade, allowing water to infiltrate to the existing soils beneath the pavement. A Geotechnical Report prepared by ZZA-Terracon (Appendix B) indicates the soils below the topsoil are 2 to 5 feet ofloose to medium density silty sand, which is then underlain by dense to very dense sand with varying amounts of silt and gravel. In reviewing the sieve analyses for Borings B-2 and B-4, which are generally the closest to the 10 11/12/2015 11'46 AM \ \m2\dfs\Bothcll\Dw.\REN\113-104\04 StOIIIlwa.ter Repott\TIR\TIR435 PZ Project 2015_11-11 .Joa City of Renton Technical Information Report November 2015 Highlands 435 Pressure Zone Reservoirs project improvements, the project DtO size (10 percent of the material passing the sieve size listed) would be 0.05 millimeters. Using guidance from Ecology's Stormwater Management Manual far Western Washington the infiltration rate for this soil is 0.73 inches per hour. The pavement was modeled using KCRTS and was determined that this method would indeed infiltrate all stormwater from the proposed impervious roadway. Based on the area of flow control BMPs calculations it was determined that 0.079 acres was required to be infiltrated. This resulted in 230 linear feet nf a 15-foot-wide road constructed with the permeable subgrade for the Honey Creek Basin TDA. The areas where this road section will be used are shown on the site plan in Appendix G. The calculations and typical road sections are also found in Appendix G. The project proposes to connect any proposed roof downspouts using a perforated pipe connection. JOHNS CREEK BASIN TOA PERFORMANCE STANDARDS (PART C) The area specific Flow Control Standard is Peak Rate Flow Control Standard -Match Existing. The proposed project does not contain pollution-generating surfaces and, therefore, water quality control facilities are not proposed. HONEY CREEK TOA PERFORMANCE STANDARDS (PART C) The area specific Flow Control Standard is Flow Control Duration Standard -Matching Forested Site Conditions. The proposed project does not contain pollution-generating surfaces and, therefore, water quality control facilities are not proposed. JOHNS CREEK BASIN TOA FLOW CONTROL SYSTEM (PART 0) A flow control facility is proposed for this project in the form of a detention vault. The City's Water Department staff were unsuccessful in obtaining an easement from downstream property owners to route a storm pipe across their property for connecting to the storm system in Sunset Boulevard. As such, a pump will be included in the proposed detention vault that will pump the stormwater from the vault up to the gravity system in NE 12"' Street which will combine with the Sunset Boulevard storm system further downstream in the system. It is anticipated that the pumped system will restore the historic flow patterns of the site by discharging to Johns Creek instead of maintaining the basin transfer to Honey Creek that was created by the retirement residence development north of the project site (as described above in the Off-site Analysis section). It is expected that the pump will be equipped with a variable frequency drive (VFD) which will include monitoring of the vault level to match the stage- discharge performance of the outlet structure designed in KCRTS. The pump will discharge to a private catch basin located on the project site near NE 12"' Street, which will in-turn be connected to the gravity-conveyance system located within NE 12"' Street. Specific details and specifications for the pump will be developed at the Utility Construction Permit application submittal stage. A proposed gravity conveyance system will be constructed in NE 12"' Street to convey stormwater to the west and to evenmally connect to the existing gravity storm system in NE 12th Street, south of Monroe Avenue. The proposed gravity system will be designed and the 11 11/12/201511'46 AM \ \rh2\dfs\Bothcll\Dau\REN\113-104\04Stocmwatcr fuport\TIR\TIR 435 PZ Project 2015_11-11 .docx City of Renton Technical Information Report November 2015 Highlands 435 Pressure Zone ReseNoirs existing downstream systems analyzed at the time of Utility Construction Permit application. Refer to Appendix E, which contains a map showing the proposed pressure force main pipe and downstream flow path for the stormwater pump discharge. Frontage improvements are also required for the proposed project, including the addition of curb and gutter, planter strip and sidewalk. The frontage improvements include traditional curb/ gutter with sidewalks sloped toward the road, and are not easily directed to the storm detention facility because of hydtaulics. As such, for the purposes of modeling, it was assumed that runoff from the new impervious surfaces of the sidewalk and the plater strip could not be routed to the detention facility and therefore were modeled as bypass areas. ALIERNAIE FOR FRONTAGE SURFACE WAIERMANAGEMENT At the time of Utility Construction Permit application, the City Water Department may elect to incorporate additional low-impact development techniques for the proposed frontage improvements. The curb and gutter may incorporate curb cuts allowing stormwater to flow off the roadway and into the adjacent planter strip. The planter strip will act as a swale allowing water to filter and partially infiltrate. Any excess stormwater that cannot infiltrate will then flow over the proposed sidewalk, which can be sloped to drain toward the site for dispersion on the site. This would mimic the existing conditions wherein the existing road runoff sheet flows onto the site tends to disperse into the existing grass surfaces without any defined channelized flow. Appendix G contains the frontage improvement details. The asphalt pavement along the frontage is existing and no new or replaced impervious surfaces are proposed for the driving lanes; therefore, the asphalt is not subject to detention or water quality treatment requirements because it already exists. However, some level of treatment and dispersion could be achieved by allowing the road runoff to disperse and infiltrate through the planter strip. The proposed sidewalk for the frontage improvements is a new impervious surface. Basic dispersion could be considered as a flow control BMP, thus the dispersed impervious area (sidewalk) could be modeled as 50 percent impervious and 50 percent grass in the KCRTS modeling software as per KCSWD Table 1.2.3.C. Due to the planter strip being the same cover as existing conditions, there will be no change in peak flow from this area and it was modeled as such. Appendix H contains the KCRTS Calculations. Flow Control BMPs are proposed in the form of infiltrating road base for the target impervious surface (described above). HONEY CREEK BASIN TOA FLOW CONTROL SYSTEM (PART 0) A flow control facility is proposed for this project in the form of a detention vault. Stormwater detention has been sized to meet Flow Control Duration Standard -Matching Forested Site Conditions. Frontage improvements are also required for the proposed project, including the addition of curb and gutter, planter strip, and sidewalk. The frontage improvements include traditional curb/ gutter with sidewalks sloped toward the road and are not easily directed to the storm detention facility because of hydraulics. As such, for the purposes of modeling, it was assumed that runoff from the new impervious surfaces of the sidewalk and the plater strip could not be routed to the detention facility and therefore were modeled as bypass areas. 12 11/12/201511,4<iAM \ \i:b2\dh\Bothtll\Data\REN\113-10-4\0-4 Stormwatct Rcport\TIR\TIR 435 PZ Project 2015_11-tl .doa City of Renton Technical Information Report November 2015 Highlands 435 Pressure Zone Reservoirs ALIERNAIE FOR FRONTAGE SURFACE WAIERMANAGEMENT At the time of Utility Construction Permit Application, the Water Department may elect to incorporate additional low-impact development techniques for the proposed frontage improvements. The curb and gutter may incorporate curb cuts allowing stormwater to flow off the roadway and into the adjacent planter strip. The planter strip will act as a swale allowing water to filter and partially infiltrate into the planter. Any excess stormwater that cannot infiltrate will flow over the proposed sidewalk, which can be sloped toward the site to allow for full dispersion on-site. This would mimic the existing conditions wherein the existing road runoff that sheet flows onto the site tends to disperse into the existing grass surfaces without any defined channelized flow. Appendix G contains the frontage improvement details. The asphalt pavement along the frontage is existing, and no new or replaced impervious surfaces are proposed for the driving lanes; therefore, the asphalt is not subject to detention or water quality treatment requirements as it already exists. However, some level of treatment and dispersion could be achieved by allowing the road runoff to disperse and infiltrate through the planter strip. The proposed sidewalk for the frontage improvements is a new impervious surface. Basic dispersion could be considered as a flow control BMP, thus the dispersed impervious area (sidewalk) could be modeled as SO-percent impervious and SO-percent grass in the KCRTS modeling software, as per KCSWD Table 1.2.3.C. Due to the planter strip being the same cover as existing conditions, there will be no change in peak flow from this area and it was modeled as such. Appendix H contains the KCRTS Calculations. Flow Control BMPs are proposed in the form of infiltrating road base for the target impervious surface (described above). WATER QUALITY SYSTEM (PART E) A formal water quality control facility is not proposed for this project. SECTION 5 -CONVEYANCE SYSTEM ANALYSIS AND DESIGN An on-site piped conveyance system exists on the project site, and additional piped conveyance systems are proposed as a part of this project. The preliminary conveyance design has been provided for this permit submittal package. For the Johns Creek TDA, an on-site conveyance system will be developed to route runoff from existing and proposed surfaces to the proposed detention vault. The detention vault will contain a pump with a VFD to pump water up to NE 12"' Street where a gravity-conveyance system will be constructed and routed to the west to connect to the existing gravity storm- conveyance system in NE 12"' Street. For the Honey Creek TDA, the runoff from the unaffected portion of the site will be routed to a proposed piped conveyance system which will replace the existing on-site system. The flow will then outfall to the existing system to the northeast of the project site. The proposed conveyance systems are to be designed in accordance with RKCSWDM Section 1.2.4.1. For the final design the proposed pipes will be sized to convey and contain the 2S- year peak flow at a minimum, and any ovcrtopping of the system up to the 100-year event will be routed as appropriate to the detention facility and discharge at the natural location (Honey Creek) or the pumped system Qohns Creek). The tributary area is less than 10 acres; therefore, in accordance with RKCSWDM Table 3.2, the Rational Method will be used to size and 13 11/12/2015 11,46 AM \ \rh2\dfs\Bothell\Dat:a.\REN\ t 13-104\04 St0rmWll.ttt Report\ TIR \TIR 435 PZ Projeo: 2015_11-11 .doa City of Renton Technical Information Report November 2015 Highlands 435 Pressure Zone Reservoirs confirm conveyance components in conjunction with backwater analyses. The sizing, confirmation and final design of conveyance components and layout will be provided for the Utility Construction Permit application submittal. The existing on-site conveyance system will be analyzed in accordance with RKCSWDM Section 1.2.4.2. There will be a change in flow characteristics since some of the proposed pipes will connect to the existing conveyance system. This requires the existing conveyance systems to have sufficient capacity to convey and contain the 10-year peak flow at a minimum, and be designed so that the 100-year event will not create or aggravate a severe flooding problem or severe erosion problem for either TDA. In accordance with RKCSWDM Section 4.2.1.2, the existing pipes need to be analyzed via a backwater analysis to confirm conveyance capacity. At the time that the Utility Construction Permit Application is prepared, Appendix I will contain the analyses of the existing and proposed conveyance systems. SECTION 6 -SPECIAL REPORTS AND STUDIES A Geotechnical Report has been prepared for the project site and is included in Appendix B. Other special reports or studies have not been prepared for this project. SECTION 7 -OTHER PERMITS In addition to this Full Drainage Review, RH2 anticipates that the following City Permits will be required: • State Environmental Protection Act (SEP A) compliance; • Fill and Grade Permit; • Conditional Use Permit; • Critical Areas Review; and • Utility Construction Permit. An Ecology Construction Stormwater General Permit will be required since the proposed project will disturb more than 1 acre of land. This will require the City Water Department to prepare a Construction Surface Water Pollution Prevention Plan (SWPPP, known as a CSWPPP in the RKCSWDJ\.1), submit a Notice of Intent (NOi) and publish associated public notices. These documents will be prepared at a future date. The project will also require review and approval from the Washington State Department of Health for potable water facilities. 14 11/12/20151U6AM \\rb2\dfs\Bothcll\Data\REN\113--104\04StottnwataRcpon\TIR\TIR 435 PZ Project 2015_11-11 .doc: City of Renton Technical Information Report SECTION 8-CSWPPP ANALYSIS AND DESIGN November 2015 Highlands 435 Pressure Zone Reservoirs The CSWPPP will be updated prior to submitting documents for construction and permitting approval. ESC PLAN ANALYSIS ANO DESIGN (PART A) ESC MEASURES Clearing Limits Half of the existing site is already cleared anc.l developed, the other half will require clearing and grubbing to construct the proposed improvements. The proposed work will nerally require construction of cast in place concrete structures, mechanical pi and landscaping that extend throughout the project site. As such generally be dictated as the property boundaries. The project Pl"fll s limits. (e lW It seems that physical delineation oft · roperty with high visibility fencing or stake and wire fencing w e Jt to the contractor, especially since the existing site perimet , enced in. Trees within the construction area that are to be pres meated on the plans, and trees to be removed are clearly marked on the la . Notes are provided on the plans to indicate that prior to beginning land disturbin 1vities, including clearing and grading, trees to be preserved and trees to be removed will be clearly marked. Notes are provided on the plans to preserve native vegetation to the maximum extent possible, particularly on slopes. Applicable BMPs: Preserving Natural Vegetation Cover Measures Exposed and unworked soils will be temporarily or permanently stabilized through the use of hydroseeding, mulching, nets/blankets, plastic covering, crushed rock surfacing, cold-mix asphalt, permanent asphalt or concrete paving. The areas to be permanently stabilized are shown on the plans and generally consist of asphalt pavement, concrete pavement and grass sod. (Note: City of Renton requires restoration using grass sod due to issues with lawn establishment via seeding.) Cut and fill slopes and trench restoration in lawn areas will most commonly be protected using mulching and sodding. From October 1 through April 30, no soils shall remain exposed and unworked for more than two days. 1bis two-day requirement may be applied at other times of the year if storm events warrant more conservative measures. From May 1 to September 30, no soils shall remain exposed and unworkcd for more than seven days. These stabilization requirements apply to all soils on site, whether at final grade or not. Exposed soil must be covered immediately at the threat of rain. These time limits may be adjusted by the local permitting authority if it can be shown that the average time between storm events justifies a different standard. 15 ll/12/201511'46AM \ \rh2\dfs\Bothell\D11.m\REN\t13.104\04 Stormwarer Rcport\TIR\TIR435 PZ Pro)CCt 2015_11-11 .doa City of Renton Technical Information Report Applicable BMPs: Mulching Nets and Blankets Plastic Covering Sodding Pflimeter Protl'Ction November 2015 Highlands 435 Pressure Zone Reservoirs To the extent possible, the duff layer, native top soil an in an undisturbed state. This will provide good er ton in itself. Since the project site will remain entirely inhabited b , e !r · ressure Zone Project, the contractor must use a phased constru i act.\, 1t disturbed areas to one parking lot at a time, or one area of wal · re . ccause the proposed construction will be phased in r@_i ally disturb and leave large areas of exposed soil subject to .~f not anticipated that substantial perimeter protections will be necessary and/ or b a . Any runoff from the site will be routed through a catch basin that will be equippe with inlet protection to filter sediment, see the Sediment Retention Section in this TIR below. T refftc A~a S tabiliZfltion Construction vehicle access will be limited to the existing driveway for the site off SE 204"' Street, although it is anticipated that some construction vehicles may occasionally exit the site via the existing driveway at Benson Highway. The access points and construction vehicle parking are already stabili2ed with asphalt pavement. It is not anticipated that substantial vehicle travel will occur between paved areas and areas where the existing pavement is removed, hence limiting sediment tracking. Any sediment transported off the project site onto existing roads will require daily clean-up utilizing shoveling and/ or pickup sweeping, and the refuse shall be transported to a controlled sediment disposal area. It is not anticipated that a wheel wash will be required. Dust will primarily be controlled using limited clearing techniques of phased construction, stabili2ing surfaces with crushed surfacing and watering. It is not anticipated that dust palliatives will be required at the project site. Sediment Retention The project does not propose a sediment pond or trap since it is not anticipated that substantial areas of exposed soils will exist during construction, and a location for siting such a facility is not readily feasible on the already developed site. To the extent possible, the duff layer, native top soil and natural vegetation shall be retained in an undisturbed state. Storm drain inlets operable during construction will be protected so that stormwater runoff does not enter the conveyance system without first being filtered or treated to remove sediment. Prefabricated, below-grate inlet protection devices will be installed following construction of the proposed catch basins to trap sediment at the catch basins. Inlets will be inspected regularly to ensure their functionality. 16 11/12/2015 11'46 AM \ \th2\dfs\Bothcll\Data\REN\II3-104\04 Stormwuc::t Rcport\TIR\TIR435 PZ Project 2015_11-11 .do~ City of Renton Technical Information Report Applicable BMPS: Preserving Natural Vegetation Storm Drain Inlet Protection Surface Irater Collection November 2015 Highlands 435 Pressure Zone Reservoirs Dust will be controlled through the use of phased construction to limit disturb areas, watering and/ or vacuum street sweepers. Flow Control The project does not propose flow control facilities. ESC PERFORMANCE.AND COMPLIANCE PROVISIONS The changing conditions typical of construction sites call for frequent field adjustments of existing ESC measures or additional ESC measures in order to meet required performance. In some cases, strict adherence to specified measures may not be necessary or practicable based on site conditions or project type. In other cases, immediate action may be needed to avoid severe impacts. Therefore, careful attention must be paid to ESC performance and compliance in accordance with the following provisions. ESC Srperoi.ror City of Renton has negotiated with the general contracting firm, W.G. Clark. W.G. Clark possesses multiple staff members qualified to perform the role of ESC Supervisor and they propose to use Trevor Johnson, Superintendent for the ESC Supervisor on the 435 Pressure Zone Project. Monitoring of Discharges The ESC supervisor from W.G. Clark will have a turbidity meter on-site and shall use it to monitor surface and stormwater discharges from the project site whenever runoff occurs from on-site activities and during storm events. The project site is subject to a NPDES general permit for construction issued by the Washington State Department of Ecology, and the project will comply with the monitoring requirements of that permit. ESC Performance ESC measures shall be applied/installed and maintained to prevent, to the maximum extent practicable, the transport of sediment from the project site to downstream drainage systems or surface waters or into on-site wetlands, streams, or lakes or onto adjacent properties. This 17 11/12/20151H6AM \ \rh2\dfa\Bothcll\Data\REN\113-104\04StonnWllter Repon\TIR\TIR 435 PZ Pwject2015_11-11 .dott City of Renton Technical Information Report November 2015 Highlands 435 Pressure Zone Reservoirs performance is intended to be achieved through proper selection, installation and operation of the above ESC measures as detailed on the plan sheets. However, the ESC supervisor or King County may determine at any time during construction that the approved measures are not sufficient and that additional action is required based on any of the following criteria. 1) If a turbidity test of surface and stormwater discharge leaving the project site is greater than the benchmark value of 25 NTIJ (nephelometric turbidity units) set by the Washington State Department of Ecology, but less than 250 NTU, the ESC Supervisor shall: a) Review the ESC plan for compliance and make appropriate 31v~~ the discharge that exceeded the benchmark of 25 NTU · (£,lb~ 7 days of b) Pully implement and mamtam appropnaM soon as possible but no later than 10 days after the d1schar e at~ enchmark; and c) Document ES~ 1 f n mtenance m the site log book. 2) stormwater entermg on-slle wetlands, streams or lakes indicat~ greater than 5 NTU above background when the background turbidil1kz or less, or 10 percent above background when the background turbidi . 1s greater than 50 NTU, then corrective actions and/ or additional measures beyond those specified in Section 1.2.5.1 shall be implemented as deemed necessary by the King County inspector or on-site ESC supervisor. 3) If discharge turbidity is 250 NTIJ or greater, the ESC Supervisor shall: a) Notify King County by telephone; b) Review the ESC plan for compliance and make appropriate revisions within 7 days of the discharge that exceeded the benchmark of 25 NTIJ; c) Fully implement and maintain appropriate ESC measures as soon as possible but no later than 10 days after the discharge that exceeded the benchmark; d) Document ESC implementation and maintenance in the site log book; and e) Continue to sample discharges until turbidity is 25 NTIJ or lower, or the turbidity is no more than 10 percent over background turbidity. 4) If King County determines that the condition of the construction site poses a hazard to an adjacent property or may adversely impact drainage facilities or water resources, then additional measures beyond those specified in Section 1.2.5.1 may be required by King County. STORMWATER POLLUTION PREVENTION AND SPILL (SWPPS) PLAN (PART 8) This SWPPS Plan shall be kept on site at all times and consists of three elements: the SWPPS Site Plan in the plan set; the Pollution Prevention Report; and the Spill Prevention and Cleanup Report. The contractor shall provide a copy of this SWPPS Plan to all subcontractors and have the subcontractors return a signed form that states the subcontractors have read and agree to the SWPPS Plan. 18 ll/12/201511'46AM \ \th2\dfs\Bothell\Dati1\REN\113---104\04 StonnwaterRepon\TIR\TIR 435 PZ Proiecr2015_11-11 .doo: City of Renton Technical Information Report POLLUTION PREVENTION REPORT November 2015 Highlands 435 Pressure Zone Reservoirs All pollutants, including waste materials, that occut during construction will be handled and disposed of in a manner that does not cause environmental contamination. Material Safety Data Sheets (MSDS) shall be kept on the project site and reviewed prior to use of any associated liquids or materials. Storage and Handling of Liquids Source: The following liquids will likely be handled or stored onsite: pctroleu products, fuel, solvents, detergents, paint, pesticides, concrete admixtures and form ),;i se liquids shall be stored in the original containers shipped by the manufac!JJ[, lJ in a manner consistent with the manufacturers' recommendations @ create pollution. It is anticipated that product size will be S gall~o~s condary containment shall be provided for all liquids stored on the si [,Li;; lY~ Monitoring: Places for id e inspected at least weekly to confirm containers are not leakin c . containment is intact. Handling of the liquids shall be monit~@;· abels on the original containers to ensure handling is consistent with~ crs' recommendations. Pcrso e Responsible: Trevor Johnson, Superintendent, (206) 624-5244 or (206) 708-9801 Storage and Stockpiling of Construction Materials and W a.rtes Soutce: Construction materials and wastes that may be generated or stockpiled onsite are anticipated to be asphalt, concrete, crushed rock and soil. The locations where these materials and wastes will be generated and stockpiled are generally in the parking areas of the project site. For any materials stockpiled, plastic covering shall be installed per the detail and notes on the plan sheets to keep rainwater from contacting construction materials and wastes that can contribute pollutants to storm, sutface and ground water. If wastes are kept in containers, they shall have secute lids that keep rainwater out of the containers. Monitoring: Construction wastes that are stockpiled onsite shall be visually inspected to ensure that proper plastic covering is provided to keep rainwater from contacting the materials. If waste containers are provided, they shall be inspected to ensute the lids are closed and secure after depositing material. Personnel Responsible: Trevor Johnson, Superintendent, (206) 624-5244 or (206) 708-9801 Fueling Source: It is anticipated that fueling operations will occur via mobile truck mounted fueling tanks. Fueling operations shall be located to ensure leaks or spills will not discharge, flow or be washed into the storm drainage system, surface water or groundwater. Drip pans and/ or absorbent pads shall be used capture drips or spills during fueling operations. If fueling occurs <luting evening hours, the contractor shall provide a mobile lighting unit. 19 11/12/2015 1 L46 AM \ \rh2\d&\Bothdl\Data\REN\113·104\04StormWll.ter Report\TIR\TIR 435 PZ Pmjw 2-015_11-11 .docx City of Renton Technical Information Report November 2015 Highlands 435 Pressure Zone Reservoirs Monitoring: Fueling operations and areas around them shall be visually inspected before, during and after fueling to evaluate and ensure a spill does not exist or occur. Personnel Responsible: Trevor Johnson, Superintendent, (206) 624-5244 or (206) 708-9801 Maintenance, Repairs, and S ftJrage ef Vehicles and Equipment Source: Maintenance and repair areas shall generally be located within the existing parking areas of the site. Use of drip pans or plastic beneath vehicles is required. The contractor shall implement spill prevention techniques during all maintenance activities. Collection and storage shall be done using containers approved for sueh use. Disposal of vehicle fluids shall be in conformance with all applicahle laws .and regulations. All spills shall be repjrted to the Washington Emergency Management Division at 1-800-258-5990, ~tio'l?!,lt®J::se Center at 1-800-424-8802 and Department of Ecology at 1-425-649-7000/:Ql~ 11, No vehicle washing may occur on the projec~~If esignated for vehicle maintenance, signs must be posted that state no ~ w may occur in the area. Monitoring: Areas for mainte p:U; rage of vehicles shall be visually inspected to ensure that a leak o e ·· r occur. Vehicles shall be inspected at least weekly for signs of any Concretes Source: The project will require the installation of concrete wallcways; therefore, the contractor will be required to wash concrete chutes within an area that does not have conveyance to the surface water. The contractor shall provide necessary sumps within the project site. Hand tools including, but not limited to, screeds, shovels, rakes, floats and trowels shall be rinsed at the same sump location(s). Sawcutting of pavement requires vacuuming of the slurry and cuttings following the operation. The slurry and cuttings will be disposed of in a manner that does not violate groundwater and surface water quality standards. The slurry will not be allowed to remain on the pavement overnight. Monitoring: The responsible person for this spill control item shall inspect wash areas during all wash outs to ensure no conveyance to surface water occurs. Sawcutting of pavement shall be visually inspected during the cutting process to ensure that slurry and cuttings are immediately removed and properly disposed of. Personnel Responsible: Trevor Johnson, Superintendent, (206) 624-5244 or (206) 708-9801 Handling of pH Elevated Water Source: It is not anticipated that the proposed concrete wallcways will cause collected water to have an elevated pH. In the event that water does collect and generate an elevated pH, this water cannot be discharged to storm or surface water until neutralized. The contractor shall provide methods for neutralizing the pH and/ or disposing of it without violating groundwater and surface water quality standards Monitoring: The responsible person shall review areas before concrete pours to identify locations where the potential exists to create a pooling of pH elevated water. After concrete 20 11/12/2015 11,46 AM \ \rh2\dfs\Bothell\Dau.\REN\113-104\04 Stomrwll.W: Rq>on\TIR\TIR 435 PZ Project 2015_11-11 .doc: City of Renton Technical Information Report November 2015 Highlands 435 Pressure Zone Reservoirs pours, any areas identified shall be monitored by the responsible individual. Testing shall occur if elevated pH water is suspected. Personnel Responsible: Trevor Johnson, Superintendent, (206) 624-5244 or (206) 708-9801 Application of Chemicals, including Pesticides and Fertilizers Source: It is anticipated that fertilizer may be used on the project to establish lawn (sod) for landscaped areas that are disturbed. It is anticipated that weed killer may be used prior to establishing paved areas, which are delineated on the plans as asphalt paving with subgrade. Chemicals shall be stored in the contractor's trailer or tools storage box and secondary containment for the chemicals shall be provided. Application of agricultural chemicals, including fertilizers and herbicides, shall be conducted in a manner and at application rates that will not result in loss of chemical to stormwater runoff. l\fanufacturers' recommendations for application rates and procedure]lshall be followed. tM . a contamers 1 le individual shall The following activities are anticipated for the project site and the associated BMPs from the King County Stormwafer Pollution Prevention Manual and Stormwater Management Manual for Western Washington are included in Appendix K • Activity Sheet A-4: Storage of Soil, Sand, and Other Erodible Materials • Activity Sheet A-17: Fueling Operations • Activity Sheet A-18: Engine Repair and Maintenance • Activity Sheet A-20: Concrete and Asphalt at Temporary Sites • Activity Sheet A-26: Landscaping Activities • BMP C151: Concrete Handling • BMP Cl 52: Sawcutting and Surfacing Pollution Prevention SPILL PREVENTION AND CLEANUP REPORT MSDS shall be kept on the project site and reviewed prior to use of any associated liquids or materials. Sources of a spill are generally consistent with the activities described above in the Pollution Prevention Report and include the following. • Storage and Handling of liquids 21 11/12/20151H<iAM \ \rh2\dfti\Bothell\Dau.\REN\113-104\04 S1onnw.1.ter Repon\TIR\TIR 435 PZ Project 2015_11-1 l .docx City of Renton Technical Information Report November 2015 Highlands 435 Pressure Zone Reservoirs • Storage and Stockpiling of Construction Materials and Wastes • Fueling • Maintenance, Repairs, and Storage of Vehicles and Equipment • Concrete Saw Cutting, Slurry and Washwater Disposal • Handling of pH Elevated Water • Application of Chemicals, including Pesticides and Fertilizers Spill prevention BMPs are the same as implementing the strategies listed above in the Pollution Prevention Report. Additional B:tviPs include the following good housekeeping practices. • ·orll • • • • Whe • Man unless recommended by the of a product will be used up before disposing of the container. urers' recommendations for proper use and disposal will be followed. • The site superintendent will inspect daily to ensure proper use and disposal of materials. The person responsible for spill prevention and cleanup is Trevor Johnson, Superintendent, (206) 624-5244 or (206) 708-9801. Procedures for monitoring spill prevention shall be via informing construction crews to inform the spill prevention lead (responsible person) of any spills and to monitor activities as described in the Spill Prevention Report as detailed above. The following procedures are provided as a guideline for responding to a spill, and the contractor will need to develop procedures specific to the construction operations as appropriate. 1. Immediately alert area occupants and supervisor, and evacuate the area, if necessary. 2. If there is a fire or medical attention is needed, contact Emergency Services at 911. 3. Attend to any people who may be contaminated. Contaminated clothing should be removed immediately and, if appropriate, the skin flushed with water. Clothing should be laundered before reuse. Seek first aid for chemical exposures as appropriate. 4. If a volatile, flammable material is spilled, immediately warn everyone, control sources of ignition and ventilate the area. 5. Don personal protective equipment as appropriate to the hazards. Refer to the MSDS or other references for information. 22 11/12/2015 11,M; AM \ \di.2\dfs\Bothcll\Data\REN\ll3-l04\04 StoIIIIW'lta R.cport\TIR\TIR.435 PZ Project 2015_11-tl .doa City of Renton Technical Information Report November 2015 Highlands 435 Pressure Zone Reservoirs 6. Consider the need for respiratory protection. The use of a respirator or self-contained breathing apparatus requires specialized training and medical surveillance. Never enter a contaminated atmosphere without protection or use a respirator without training. If respiratory protection is needed and no trained personnel are available, call F.m~r>ency Sen·iccs at 911. If respiratory protection is used, be sure there is another rsnn outside the spill area in communication, in case of an emergency. I~no ,~ · able, contact Emergency Services. @~ ll, ~- 7. If the spill is large, there has been a release ~h,&,cn r there is no one knowledgeable about spill clean-up available, '1Q(9'. ncy Services at 911. 8. Protect drains or other me~m~ a release. Spill socks and absorbents may be placed arm 'll~ . 9. If appro n can-up the spill accordingly. Spill control materials may be distr· e entire spill area, working from the outside, circling to the inside. This re e chance of splash or spread of the spilled chemical. 10. When spilled materials have been absorbed, use tools to brush and scoop the materials to remove them to an appropriate container. Polyethylene bags may be used for small spills. Five gallon pails or 20 gallon drums with polyethylene liners may be appropriate for larger quantities. 11. Complete a hazardous waste sticker, identifying the material as Spill Debris involving XYZ Chemical, and affix onto the container. Spill control materials will probably need to be disposed of as hazardous waste. Contact the Washington State Department of Ecology for advice on storage and packaging for disposal. 12. If appropriate, decontaminate the surfaces where the spill occurred using a mild detergent and water. The contractor shall maintain spill response materials at the job trailer and/ or tools storage box. Sample worksheets are provided in Appendix J for recordkeeping and reporting. The following activities are anticipated for the project site and the associated BMPs from the King County S tormwater Pollution Prevention Manual and S tormwater Management Manual far Western Washington are included in Appendix K • Activity Sheet A-4: Storage of Soil, Sand, and Other Erodible Materials • Activity Sheet A-17: Fueling Operations • Activity Sheet A-18: Engine Repair and Maintenance • Activity Sheet A-20: Concrete and Asphalt at Temporary Sites • Activity Sheet A-26: Landscaping Activities • BMP C151: Concrete Handling • BMP Cl 52: Sawcutting and Surfacing Pollution Prevention 23 11/12/201511'46AM \ \rh2\dfs\Bothcll\Da.ta\REN\113-104\04 Stormw:ater Report\TIR\TIR 435 PZ Project 2015_11-l l .doot City of Renton Technical Information Report November 2015 Highlands 435 Pressure Zone Reservoirs SECTION 9 -BOND QUANTITIES, FACILITY SUMMARIES AND DECLARATION OF COVENANT In accordance with RKCSWDM Section 1.2.7 -Core Requirement No. 7 -Financial Guarantees and liability, all persons constructing any surface water facilities are required to post with the City of Renton a bond, assignment of funds or certified check. For this project the City of Renton's Water Department requests that this requirement be waived, consistent with RCW 35.21.470, which states: "A city or town may not require any state agency or unit oflocal government to secure the performance of a permit requirement with a surety bond or other financial security device, including cash or assigned account, as a condition of issuing a permit to that unit of local government for a building construction project. As used in this section, "building construction project" includes, in addition to its usual meaning, associated landscaping, street alteration, pedestrian or vehicular access alteration, or other amenities or alterations necessarily associated with the project." The Declaration of Covenant is not anticipated to be required since the facilities are to be owned by the City of Renton. SECTION 10 -OPERATIONS AND MAINTENANCE MANUAL The operations and maintenance manual can be found in Appendix L. The elements covered are as follows. 1. Control Structure/Flow Restrictor (Spill Control Manhole) 2. Catch Basins and Manholes 3. Conveyance Pipes and Ditches 4. Debris Barriers This concludes the Technical Information Report. 24 11/12/201511,46 AM \ \rh2\dfs\Bothdl\Data\REN\113-I04\04Stottnvnter Report\TIR\TIR 435 PZ Ptojcct 2015_11-tt .doa: APPENDICES APPENDIX A WORKSHEETS AND FORMS !Figure 1 a KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL TECHNICAL INFORMATION REPORT (TIR) WORKSHEET Part 1 PROJECT OWNER AND PROJECT ENGINEER Project Owner City of Renton Phone 425.430.7394 Address 1055 S. Grady Way Renton, WA 98057 Project Engineer Bret Beaupain, P.E. Company RH2 Engineering, Inc. Phone 425.951.5382 Part 3 TYPE OF PERMIT APPLICATION D Landuse Services Subdivison / Short Subd. / UPD D Building Services M/F / Commerical / SFR D Clearing and Grading D Right-of-Way Use lfil Other Public Facilitv Part5 PLAN AND REPORT INFORMATION Technical Information Report Type of Drainage Review @t Targeted (circle): Large Site Date (include revision See cover of this dates): QQ!.l.llll!lllt. Date of Final: Part 6 ADJUSTMENT APPROVALS I Part 2 PROJECT LOCATION AND DESCRIPTION Project Name Highlands Reservoir ODES Permit# --~N~/A~----- Localion Township ~2=3~N~--- Range -~5~E'------ Section -~9 ____ _ Site Address 3410NE 12th St Renton, WA Part4 OTHER REVIEWS AND PERMITS D DFWHPA D Shoreline D COE404 Management D DOE Dam Safety W Structural RockeryNault/ __ D FEMA Floodplain D ESA Section 7 D COE Wetlands D Other Site Improvement Plan (Engr. Plans) Type (circle one): @Dt Modified I Small Site Date (include revision See Plans. dates): Date of Final: Type (circle one): Standard / Complex / Preapplication / Experimental/ Blanket Description: (include conditions in TIR Section 2) Date of Annroval: 2009 Surface Water Design Manual 1/9/2009 !Figure 1a KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL TECHNICAL INFORMATION REPORT (TIR) WORKSHEET Part7 MONITORING REQUIREMENTS Monitoring Required: Yest@ Describe: Start Date: Completion Date: Part 8 SITE COMMUNITY AND DRAINAGE BASIN Community Plan: _N~rt~,A·~---------- Special District Overlays: -'N."-'1/;;;;'A.__ ___________________ _ Drainage Basin:-,--~ N/~A,'--c-.,..,...,---------- Stormwater Requirements: ~N=/=A~------------------- Part 9 ONSITE AND ADJACENT SENSITIVE AREAS lfil River/Stream See Attached Map 0 Lake D Wetlands __________ _ 0 Closed Depression -------- 0 Floodplain _________ _ 0 Other __________ _ Part 10 SOILS Soil Type Slopes SEE GEO REPORT D High Groundwater Table (within 5 feet) D Other 0 Additional Sheets Attached 2009 Surface Water Design Manual 2 lfil Steep Slope See Attached Mao lfil Erosion Hazard See Attached Map lfil Landslide Hazard See Attached Map D Coal Mine Hazard ______ _ D Seismic Hazard -------- 0 Habitat Protection-------0 __________ _ Erosion Potential D Sole Source Aquifer D Seeps/Springs 1/9/2009 !figure 1a KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL TECHNICAL INFORMATION REPORT (TIR) WORKSHEET Part 11 DRAINAGE DESIGN LIMITATIONS REFERENCE LIMITATION/ SITE CONSTRAINT 0 Core 2 -Offsite Anal'.)'.sis None D Sensitive/Critical Areas D SEPA D other D D Additional Sheets Attached Part 12 TIR SUMMARY SHEET (provide one TIR Summarv Sheet Der Threshold Dischanl8 Areal Threshold Discharge Area: North Renton -Area: 1.08 Acres /name or descriotion l Core Requirements (all 8 apply) Discharae at Natural Location Number of Natural Discharae Locations: I Offsite Analysis Level: ~2/3 dated: Flow Control Level: 1 ~w 3 or Exemption Number !incl. facilitv summarv sheet) SmallS~eBM s Conveyance System Spill containment located at: Storm Detention Vault Erosion and Sediment Control ESC Site Supervisor: To be determined by Contact Phone: After Hours Phone: competitive bid Maintenance and Operation Responsibility: Private/~ If Private, Maintenance Loa Reouired: Yes /No Financial Guarantees and Liabilitv Provided: Yes /<r::!9) Water Quality Type: Basic / Sens. Lake / Enhanced Basicm / Bog (include facility summary sheet) or Exemption No. No 11Qllution-generating surfaces Landscape Management Plan: Yes / (No) Soeclal Reaulrements fas aoollcablel Area Specific Drainage Type: CDA / SDO / MDP /BP/ LMP / Shared Fae. /~ Reauirements Name: Floodplain/Floodway Delineation Type: Major / Minor / Exemption I@ 100-year Base Flood Elevation (or range): Datum: Flood Protection Facilities Describe: NIA Source Control Describe landuse: Water Reservoir & Booster Pump Station (comm./industrial landuse) Describe any structural controls: None 2009 Surface Water Design Manual 1/9/2009 3 !figure 1a KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL TECHNICAL INFORMATION REPORT (TIR) WORKSHEET Oil Control High-use Site: Yes I <t:!9) Treatment BMP: NIA Maintenance Agreement: Yes / @ with whom? NIA Other Draina11e Structures Describe: Part 13 EROSION AND SEDIMENT CONTROL REQUIREMENTS MINIMUM ESC REQUIREMENTS MINIMUM ESC REQUIREMENTS DURING CONSTRUCTION AFTER CONSTRUCTION lliJ Clearing Limits [I Stabilize Exposed Surfaces lliJ Cover Measures lliJ Remove and Restore Temporary ESC Facilities lliJ Perimeter Protection lliJ Clean and Remove All Silt and Debris, Ensure lliJ Traffic Area Stabilization Operation of Permanent Facilities lliJ Sediment Retention D Flag Limits of SAO and open space lliJ Surface Water Collection preservation areas D Other lliJ Dewatering Control lliJ Dust Control lliJ Flow Control Part 14 STORMWATER FACILITY DESCRIPTIONS (Note: Include Facllltv Summarv and Skatchl Flow Control Tvoe/Description Water Qualitv Tvoe/Descriotion [I Detention Vault D Biofiltration NIA D Infiltration D Wetpool D Regional Facility D Media Filtration D Shared Facility D Oil Control D Flow Control D Spill Control BMPs D Flow Control BMPs D Other D Other None 2009 Smface Water Design Manual 1/9/2009 4 !Figure 1 b KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL TECHNICAL INFORMATION REPORT (TIR) WORKSHEET Part 15 EASEMENTS/TRACTS Part 16 STRUCTURAL ANALYSIS 0 Drainage Easement 0 Cast in Place Vault 0 Covenant 0 Retaining Wall 0 Native Growth Protection Covenant 0 Rockery > 4' High 0 Tract None, City-owned Property 0 Structural on Steep Slope 0 Other 0 Other Part 17 SIGNATURE OF PROFESSIONAL ENGINEER I, or a civil engineer under my supervision, have visited the site. Actual site conditions as observed were incorporated Into this worksheet and the attached Technical lnfonnation Report. To the best of my kn::;;; i;Ton$;~t)dz:::· ~ ,-z.1 z. /-z-o el 2009 Surface Water Design Manual 5 1/912009 JFigure 2a KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL TECHNICAL INFORMATION REPORT (TIR) WORKSHEET Part 1 PROJECT OWNER AND PROJECT ENGINEER Project Owner City of Renton Phone 425.430. 7394 Address 1055 S. Grady Way Renton, WA 98057 Project Engineer Bret Beaupain, P.E. Company RH2 Engineering, Inc. Phone 425.951.5382 Part 3 TYPE OF PERMIT APPLICATION 0 Landuse Services Subdivison / Short Subd. / UPD 0 Building Services M/F / Commerical / SFR 0 Clearing and Grading 0 Right-of-Way Use ~ Other Public Facility Part5 PLAN AND REPORT INFORMATION Technical Information Report Type of Drainage Review @1 Targeted (circle): Large Site Date (include revision See cover of this dates): document Date of Final: Part 6 ADJUSTMENT APPROVALS I Part 2 PROJECT LOCATION AND DESCRIPTION Project Name Highlands Reservoir ODES Permit# __ _,_N"'/A'-=------- Location Township ~2=3~N~--- Range -~5_E ____ _ Section -"-9 ____ _ Site Address 3410 NE 12th St Renton, WA Part 4 OTHER REVIEWS AND PERMITS 0 DFWHPA 0 COE404 0 DOE Dam Safety 0 FEMA Floodplain 0 COE Wetlands 0 Other D Shoreline Management l!J Structural RockeryNault/ __ 0 ESA Section 7 Site Improvement Plan (Engr. Plans) Type (circle one): @I Modified Small Site I Date (include revision See Plans. dates): Date of Final: Type (circle one): Standard / Complex / Preapplication / Experimental / Blanket Description: (include conditions in TIR Section 2) Date of Approval: 2009 Surface Water Design Manual 1/9/2009 !figure 2a KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL TECHNICAL INFORMATION REPORT (TIR) WORKSHEET Part7 MONITORING REQUIREMENTS Monitoring Required: Yes/@ Describe: Start Date: Completion Date: Part 8 SITE COMMUNITY AND DRAINAGE BASIN Community Plan: ----,-~N/A""::-::-:-:---------- Special District Overlays: _.N=l'A..__ ___________________ _ Drainage Basin: ~~N=I/A~~~-------- Stormwater Requirements: .._N"'/A~-------------------- Part 9 ONSITE AND ADJACENT SENSITIVE AREAS [I River/Stream See Attached Map 0 Lake D Wetlands __________ _ D Closed Depression _______ _ D Floodplain---------- 0 Other ___________ _ Part 10 SOILS Soil Type Slopes SEE GEO REPORT D High Groundwater Table (within 5 feet) D Other D Additional Sheets Attached 2009 Surface Water Design Manual 2 [I Steep Slope See Attached Map [I Erosion Hazard See Attached Map [I Landslide Hazard See Attached Map D Coal Mine Hazard ______ _ D Seismic Hazard _______ _ D Habitat Protection ______ _ D ___________ _ Erosion Potential D Sole Source Aquifer D Seeps/Springs 1/9/2009 jFigure 2a KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL TECHNICAL INFORMATION REPORT (TIR) WORKSHEET Part 11 DRAINAGE DESIGN LIMITATIONS REFERENCE LIMITATION/ SITE CONSTRAINT D Core 2 -Offsite Anall£sis None D Sensitive/Critical Areas D SEPA D Other D D Additional Sheets Attached Part 12 TIR SUMMARY SHEET {provide one TIR Summarv Sheet Der Threshold Dlsch11111e Areal Threshold Discharge Area: {name or descriotioril North Renton Basin -Area: 1.16 Acres Core Requirements (all 8 apply) Discharae at Natural Location Number of Natural Discharae Locations: I Offsite Analysis Level: (9 2 / 3 dated: Flow Control Level: 1 ~w 3 or Exemption Number (incl. facility summarv sheet) Small Site BM s Conveyance System Spill containment located at: Storm Detention Vault Erosion and Sediment Control ESC Site Supervisor: To be determined by Contact Phone: After Hours Phone: competitive bid Maintenance and Operation Responsibility: Private/~ If Private, Maintenance Log ReQuired: Yes /No Financial Guarantees and Provided: Yes/~ Liability Water Quality Type: Basic / Sens. Lake / Enhanced Basicm / Bog (include facility summary sheet) or Exemption No. No 2ollution-generating surfaces Landscaoe ManaQement Plan: Yes / (Nii) Speclal Reauirements las applicable) Area Specific Drainage Type: CDA / SDO / MDP /BP/ LMP / Shared Fae./~ Reauirements Name: Floodplain/Floodway Delineation Type: Major / Minor / Exemption I@ 100-year Base Flood Elevation (or range): Datum: Flood Protection Facilities Describe: NIA Source Control Describe landuse: Water Reservoir & Booster Pump Station (commJindustrial landuse) Describe any structural controls: None 2009 Surface Water Design Manual 1/9/2009 3 !figure 2a KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL TECHNICAL INFORMATION REPORT (TIR) WORKSHEET Oil Control High-use Site: Yes I <t:!9) Treatment BMP: NIA Maintenance Agreement: Yes / @ with whom? NIA Other Dralnaae Structures Describe: Part 13 EROSION AND SEDIMENT CONTROL REQUIREMENTS MINIMUM ESC REQUIREMENTS MINIMUM ESC REQUIREMENTS DURING CONSTRUCTION AFTER CONSTRUCTION W Clearing Limits W Stabilize Exposed Surfaces W Cover Measures W Remove and Restore Temporary ESC Facilities W Perimeter Protection W Clean and Remove All Silt and Debris, Ensure W Traffic Area Stabilization Operation of Permanent Facilijies W Sediment Retention D Flag Limits of SAO and open space W Surface Water Collection preservation areas D Other W Dewatering Control W Dust Control W Flow Control Pert 14 STORMWATER FACILllY DESCRIPTIONS (Note: Include Facilltv Summary and Sketch) Flow Control Tvoe/Descriotion Water Qualitv Tvoe/Description W Detention Vault D Biofiltration NIA D Infiltration D Wetpool D Regional Facility D Media Filtration D Shared Facility D Oil Control D Flow Control D Spill Control BMPs D Flow Control BMPs D Other D Other None 2009 Surface Water Design Manual 1/9/2009 4 !Figure 2a KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL TECHNICAL INFORMATION REPORT (TIR) WORKSHEET Part 11 DRAINAGE DESIGN LIMITATIONS REFERENCE LIMITATION/ SITE CONSTRAINT 0 Core 2 -Offsite ooalJlsis None 0 Sensitive/Critical Areas 0 SEPA 0 Other 0 0 Additional Sheets Attached Part 12 TIR SUMMARY SHEET (provide one TIR Summary Shasl par Threshold Discharge Areal Threshold Discharge Area: Honey Creek Basin: Area: 0.96 Acres (name or description l Core Requirements (all 8 apply) Discharoe at Natural Location Number of Natural Discharoe Locations: 1 Offsite Analysis Level: (9'2/3 dated: Flow Control Level: 1 ~w 3 or Exemption Number (incl. facilitv summarv sheet) Small Site BM s Conveyance System Spill containment located at: Storm Detention Vault Erosion and Sediment Control ESC Site Supervisor: To be determined by Contact Phone: After Hours Phone: competitive bid Maintenance and Operation Responsibility: Private/~ If Private, Maintenance Loo Required: Yes /No Financial Guarantees and Liabilitv Provided: Yes/~ Water Quality Type: Basic / Sens. Lake / Enhanced Basicm / Bog (include facility summary sheet) or Exemption No. No J:!Ollution-generating surfaces Landscape Manaaement Plan: Yes / (No) Special Requirements (as applicable) Area Specific Drainage Type: CDA / SDO / MDP /BP/ LMP / Shared Fae.~ Reauirements Name: Floodplain/Floodway Delineation Type: Major / Minor / Exemption t@ 100-year Base Flood Elevation (or range): Datum: Flood Protection Facilities Describe: NIA Source Control Describe landuse: Water Reservoir & Booster Pump Station (commJindustrial landuse) Describe any structural controls: None 2009 Surface Water Design Manual 3 1/9/2009 !Figure 2a KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL TECHNICAL INFORMATION REPORT (TIR) WORKSHEET Oil Control High-use Site: Yes/~ Treatment BMP: NIA Maintenance Agreement: Yes / @ with whom? NI A other Draina11e Structures Describe: Part 13 EROSION AND SEDIMENT CONTROL REQUIREMENTS MINIMUM ESC REQUIREMENTS MINIMUM ESC REQUIREMENTS DURING CONSTRUCTION AFTER CONSTRUCTION W Clearing Limits W Stabilize Exposed Surfaces W Cover Measures W Remove and Restore Temporary ESC Facilities W Perimeter Protection W Clean and Remove All Silt and Debris, Ensure W Traffic Area Stabilization Operation of Permanent Facilities W Sediment Retention D Flag Limits of SAO and open space W Surface Water Collection preservation areas D Other W Dewatering Control W Dust Control W Flow Control Part 14 STORMWATER FACILITY DESCRIPTIONS (Note: Include Facllltv Summarv and Sketch) Flow Control Tvoe/Descriotion Water Qualitv Tvoe/Descriotion W Detention Vault D Biofiltration NIA D Infiltration D Wetpool D Regional Facility D Media Filtration D Shared Facility D Oil Control D Flow Control D Spill Control BMPs D Flow Control BMPs D Other D Other None 2009 Surface Water Design Maoual 4 1/9/2009 !Figure 2b KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL TECHNICAL INFORMATION REPORT (TIR) WORKSHEET Pert 15 EASEMENTS/TRACTS Pert 16 STRUCTURAL ANALYSIS D Drainage Easement D Casi In Place Vault D Covenant D Retaining wan D Native Growth Protection Covenant D Rockery > 4' High D Tract None, City-owned Property D Structural on Steep Slope D Other D Other Part 17 SIGNATURE OF PROFESSIONAL ENGINEER I, ore cMI engineer under my supervision, have visited the site, Actual site conditions es observed were incorporated into this worksheet and the attached Technical Information Report To the best of my kn~ infonnal:~is accurate. !!~ Iii ~ ii ............... I 'Z-L-z.. {i.o I~ 2009 Surface Water Design Manual 1/9/2009 5 City of Renton Vicinity Map -Figure 2 II II 0 11680 0 340 680 ,~, WGS _ 1984_ Web_Mercator _ Auxitiary_Sphere Cityo~-errfon (3 Finance & IT Division Legend City and Cou nty Boundary Other [:} City of Renton 11 /24/20 14 !Fig ure 4 I • Custom Soil Resource Report • ~ Soi l Map ~ ~ ~ ~ ~ 561800 56 1900 562000 562100 562700 562800 47"';(137'N I ; 47" X!37"N § § ~ ~ ~ ~ ~ j ~ i ; ~ I ~ ~ i i ; ~ & I ~ ii ; ~ i!l ~ i!l § ~ ~ ii I I 47" 'BSl 'N I 47"29'Sl'N 561000 561900 56200'.) 562100 562200 562300 56>400 S62SOO 562700 562000 • • ~ MapScale : 1:6,890lprtedo, Apatrait (8.5" x 11") sheet ~ a N -a 100 200 400 600 A -0 300 600 1200 1800 Map~: webMen:oo:r Q:rnercoorcinates : W3.584 E:dge tics : VTM Zone l(}'l YJGS84 8 !Figure 4 ! Custom Soil Resource Report MAP LEGEND Area of Interest (AOI} Area of Interest (AOI) - Soils =i Soil Map Unit Polygons -Soil Map Unit Lines • Soil Map Unit Points Special Point Future• (2' Blowout 181 Borrow Pit )i( Clay Spot 0 Closed Depression X Gravel Ptt Gravelly Spot 0 Landfill A. Lava Flow ""' Marsh or swamp 'R' Mine or Quarry 0 Miscellaneous Water 0 Perennial Waler " Rock Outcrop + Saline Spot . . Sandy Spot -Severely Eroded Spot 0 Sinkhole ~ SlldeorSllp % Sodic Spot !ii Spoil Area 0 Stony Spot m Very Stony Spot \7 WetSJk]t l\ Other .. Special Line Features Water Features Streams and Canals Transportation -- Rails Interstate Highways US Routes Major Roads Local Roads Background • Aerial Photography 9 MAP INFORMATION The soil surveys that comprise your AOI were mapped at 1 :24,000. Warning: Soil Map may not be valid at this scale. Enlargement of maps beyond the scale of mapping can cause misunderstanding of the detail of mapping and accuracy of soil line placement. The maps do not show the small areas of contrasting soils that could have been shown at a more detailed scale. Please rely on the bar scale on each map sheet for map measurements. Source of Map: Natural Resources Conservation Service Web Soil Survey URL: http://websoilsurvey.nrcs.usda.gov Coordinate System: Web Mercator (EPSG:3857) Maps from the Web Soll Survey are based on the Web Mercator projection, which preserves direction and shape but distorts distance and area. A projection that preserves area, such as the Albers equal-area conic projection, should be used if more accurate calculations of distance or area are required. This product is generated from the USDA-NRCS certified data as of the version date(s) listed below. Soil Survey Area: King County Area, Washington Survey Area Data: Version 10, Sep 30, 2014 Soil map units are labeled (as space allows) for map scales 1 :50 ,000 or larger . Date(s) aerial images were photographed: Jul 8, 201~ul 15, 2014 The orthophoto or other base map on which the soil lines were compiled and digitized probably differs from the background imagery displayed on these maps. As a result, some minor shifting ·~ L -··-..I--'-----·· L ••• • APPENDIXB GEO REPORT ~ ZZA-lrerracon 81085801 January 19, 2009 HDR Entneering, Inc. 500 1081 Avenue NE Bellevue, Washington 98004 Attention: Mr. Greg Pierson Subject: Geotechnical Report City of Renton-· Water Distribution System Storage Planning Study Renton, Washington Dear Mr. Pierson, This report presents the results of our geotechnical investigation for the City of Renton Water Distribution System Storage Study. Our scope of services included review of existing information, site reconnaissance, subsurface exploration, laboratory testing, geotechnical engineering analyses, evaluating potential geotechnical constraints for the project, and preparation of this repo1t. These services were completed in accordance with the Subconsultant Agreement dated October 3, 2008. We understand that the City of Renton is plruming to increase the storage capacity of its water system over the next 4 to 7 years. The City has identified the Highlands Site and Mount Olivet Site as two existing reservoir locations that can accommodate storage expansion for major service areas. We understand that the scope of the current study is limited to a planning level effort: The geotechnical conclusions and recommendations presented in this report are therefore preliminary in nature. PROJECT DESCRIPTION The location of the Highlands Site and existing site features are shown on Figure I, Site and Exploration Plan. The site is currently occupied by 1.5 and 2.0 MG below ground reservoirs, a 750,000 G elevated water tank, and a pump station. As currently planned, expansion of the Highlands Site would include the following. • Phase I construction of a 210 by 265 foot, 8.0 MG below ground reservoir in the undeveloped northem portion of the site. This reservoir would have an overflow elevation of 445.5 feet and a finished floor elevation of 425 feet. The latter elevation would place the finished floor I foot above to 7 feet below the existing ground surface. • New pump station located in the southem portion of the site to the west of the existing facility. 21905 641 • Avenue West Ste 100, Lynnwood, WA 98043 425-771-3304 Fax: 425-771-3549 ~ ZZA-lrerracan Water Distribution System Storage Study Renton, Washington 81085801 January 19, 2009 Page2 • Rechlorination facility located in the southern portion of the site. • Storm water detention vault located north of the Phase 1 below ground reservoir. This vault will extend about IO to 12 feet below the existing ground surface. • Several new 8 to 16 foot deep storm drain manholes. • Phase 2 demolition of the two existing below ground reservoirs and construction of a new 175 by 285 foot, 7 .9 MG below ground reservoir. This reservoir would have an overflow elevation of 445.5 feet and a finished floor elevation of 425 feet. It appears that the latter elevation would place the finished floor at a similar elevation to the existing reservoirs, and about 11 to 17 feet below the existing ground surface around the perimeter of the new reservoir. • Phase 4 construction of a 72 foot diameter, 4.1 MG standpipe. The location of the Mount Olivet Site and existing site features are shown on Figure 2. The site is currently occupied by a 115 foot diameter, 3.0 MG standpipe located in the central portion of the site. Expansion of this site would involve demolition of the existing reservoir and Phase 3 construction ofa new 140 foot diameter, 6.9 MG reservoir located at a similar location but slightly to the southwest of the existing reservoir. The new reservoir will have an overflow elevation of209.5 feet and a finished floor elevation of about 152 feet. The latter elevation would place the finished floor about 1 to 6 feet below the existing ground surface. A new retaining wall might be required on the southwest side of the new reservoir to provide access to this area. HIGHLANDS SITE SITE CONDITIONS Surface Conditions The Highlands site is bounded by NE 121h Street on the south, and by residential property on the west, no1ih, and east. The ground surface is inclined slightly downward to the north. Existing elevations range from 422 feet at the no1iheast corner to 442 feet at the soutl!east corner. Existing vegetation consists of grass with evergreen trees distributed throughout the site, particularly in the n01ihern undeveloped portion of the property. Numerous underground utilities are present at the site. Subsurface Conditions Subsmface conditions at the Highlands Site were explored by completing 6 test borings (Borings B-1 through B-6) at the locations shown on Figure 1, Site and Exploration Plan. Subsurface exploration procedures and the logs of the explorations are presented in Appendix A. Laboratory testing procedures and results are summarized in Appendix B. 21905 64'' Avenue West Ste 1001 Mountlake Terrace, WA 98043 425-771-3304 Fax: 425-771-3549 ~ ZZA-lrerracan Water Distribution System Storage Study Rentonj Washington 81085801 January I 9, 2009 Page 3 The subsurface conditions encountered in Borings B-1 through B-6 were fairly consistent. These borings encountered topsoil and 2 to 5 feet of loose to medium dense silty sand at the surface, underlain by dense to very dense sand with varying amounts of silt and gravel. The medium dense to very dense sand was encountered to the maximum depth explored of39.5 feet below the existing ground surface. No groundwater was observed in the borings at the time of drilling. Groundwater observation wells were installed in Borings B-1, B-4, and B-5 to monitor groundwater levels following drilling. No groundwater was measured in these observation wells on October 23, 2008. Groundwater levels and soil moisture conditions should be expected to vary throughout the year due to fluctuations in seasonal precipitation, and other on-and off-site factors. CONCLUSIONS AND RECOMMENDATIONS General Based on our site reconnaissance, subsurface exploration, laboratory testing and geotechnical engineering analyses, we conclude that the project site is suitable for construction of the new reservoirs, pump station, rechlorination facility, storm water detention vault and storm drain manholes. This conclusion is based, in part, on employing proper design and construction practices to accommodate the conditions discussed below. The following sections of this report contain conclusions and recommendations regarding site preparation, excavations, permanent slopes, foundation considerations, floor slab support, subgradc walls, and hydrostatic uplift. Environmentally Critical Area Considerations Section 4-3-050 of the City of Renton Municipal Code (RMC) describes the critical areas that are considered by the City of Renton during the development review process. This repo11 addresses the geologic hazards regulated under the RMC including steep slopes, erosion hazards, landslide hazards, seismic hazards, and coal mine hazards. The geologic hazard regulations apply to all nonexempt activities described in Section 4-3-050C5 on sites containing or located within 50 feet of the above hazards. Each geologic hazard is defined and described in greater detail on pages 13 through 17 of this rep011. The following sections briefly summarize these hazards as they pertain to the Highlands site. Steep Slopes The site does not contain either "sensitive slopes" or "protected slopes". 21905 64'h Avenue West Ste 100, Mountlake Terrace, WA 98043 425-771-3304 Fax: 425-771-3549 1\1 ZZA-lrerracan Erosion Hazards Water Distribution System Storage Study Renton, Washington 81085801 January 19, 2009 Page4 The site soils are defined by the USDA Soil Conservation Survey as "Arents, Alderwood material (AmC)" with slopes ranging from Oto 6 percent. The erosion hazard for these soils is slight. Therefore, the site would be classified as a "low erosion hazard (EL)". Landslide Hazards The site is would be classified as "low landslide hazard (LL)." Seismic Hazards The site is not mapped as a high seismic area in the RMC maps in Section 4-3-0SOQ. In addition, the site would be classified as a "low seismic hazard (SL) due to dense to very dense soils present at the site at shallow depth. Coal Mine Hazards The site is not mapped as having any known mine hazards in Section 4-3-0SOQ. Therefore, the site is would be classified as a "low coal mine hazard." Site Preparation Site preparation should include the removal of all vegetation, root mass, organic soils, existing pavements and structures, and any deleterious debris from construction areas including those locations where "structural fill" is to be placed. Any excavations that extend below finish grades should be backfilled with structural fill as outlined subsequently in this report. The borings at the Highlands site encountered 2 to 5 feet of loose to medium dense silty sand at the surface, underlain by dense to very dense sand with varying amounts of silt and gravel. The loose silty sand should be removed from the limits of the new reservoirs, pump station, rechlorination facility and storm water detention vault, and for a minimum distance of 5 feet beyond the perimeter of these structures. After site demolition and stripping, we recommend that the new structure areas be proofrolled and compacted to a firm and unyielding condition in order to achieve a minimum compaction level of95 percent of the modified Proctor maximum dry density as determined by the ASTM: D-1557 test procedure. Proofrolling should be accomplished with a heavy compactor, loaded double-axle dump !luck, or other heavy equipment under the observation of a representative from our firm. Areas where loose surface soils exist should be removed and replaced with structural fill. The need for or advisability of proofrolling due to soil moisture conditions should be determined at the time of construction. We recommend that a 21905 64th Avenue West Ste 100, Mountlake Terrace, WA 98043 425-771-3304 Fax: 425-771-3549 ~ ZZA-lrerracan Water Distribution System Storage Study Renton, Washington 81085801 Januaiy 19, 2009 Page 5 representative of our firm observe the soil conditions prior to and during proofrolling to evaluate the suitability of stripped subgrades. Eaithwork may be difficult during periods of elevated soil moisture and wet weather due to the moisture sensitive nature of the silty p01tions of the site soils. Subgrade soils that become disturbed due to elevated moisture conditions should be overexcavated to expose firm, non- yielding, non-organic soils and backfilled with compacted structural fill. We recommend that the earthwork portion of the project be completed during extended periods of dry weather, if possible. If earthwork is completed during the wet season (typically November through May), it may be necessary to take extra precautionary measures to protect subgrade soils. Excavations All excavations should be completed in accordance with applicable city, state, and federal safety standards. We anticipate that the site soils can be excavated using conventional eaith moving equipment. We anticipate that construction of the new below ground reservoirs and storm water detention vault might require temporary excavations up to 17 feet below existing grade. Temporary slope stability is a function of many factors, including the following: I. The presence and abundance of groundwater; 2. The type and density of the various soil strata; 3. The depth ofcut; 4. Surcharge loading adjacent to the excavation; and 5. The length of time the excavation remains open. It is exceedingly difficult under the variable circumstances to pre-establish a safe and "maintenance-free" temporary cut slope angle. Therefore, it should be the responsibility of the contractor to maintain safe slope configurations since the contractor is continuously at the job site, able to observe the nature and condition of the cut slopes, and able to monitor the subsurface materials and groundwater conditions encountered. It may be necessary to drape temporary slopes with plastic or to otherwise protect the slopes from the elements, and minimize sloughing and erosion. We do not recommend vertical slopes or cuts deeper than 4 feet if worker access is necessary. The cuts should be adequately sloped or supported to prevent injury to personnel from local sloughing and spalling. The excavation should conform to applicable Federal, State, and local regulations. Most of the soils which will be exposed in project excavations are consistent with the criteria for Type A soils presented in Chapter 296-155, Part N, Excavation Trenching and 21905 64'" Avenue West Ste 100, Mountlake Terrace, WA 98043 425-771-3304 Fax: 425-771-3549 ii ZZA-lrerracon Water Distribution System Storage Study Renton, Washington 81085801 January 19, 2009 Page6 Shoring, of the Washington Administrative Code (WAC). Consequently, we recommend that maximum temporary slope inclinations of 0. 75H: 1 V be considered for preliminary planning purposes. Temporary Shoring It is possible that temporary shoring systems might be used for some project excavations. The lateral soil pressures acting on temporary excavation support systems will depend on the ground surface configuration adjacent to the excavation and the amount oflateral movement which can occur as the excavation is made. For support systems that are free to yield at the top at least one-thousandth of the height of the excavation, soil pressures will be less than if movements are limited by such factors as wall stiffness or bracing. We recommend that yielding systems be designed using an equivalent fluid density of 35 pounds per cubic foot (pct) for a level ground surface. Similarly, we recommend that nonyielding systems be designed for a uniform lateral pressure of 28H in pounds per square foot (psf), where H is the depth of the planned excavation in feet below a level ground smface. The above recommended lateral soil pressures are based on a fully drained condition and do not include the effects of hydrostatic water pressures. In addition, the above values do not include the effects of surcharges (e.g., equipment loads, storage loads, traffic loads, or other smface loading). Hydrostatic water pressures and surcharge effects should be considered as appropriate. Construction Dewatering No groundwater was observed in the borings at the time of drilling. Construction dewatering is not expected to be a significant issue for the project. Permanent Slopes We recommend a maximum slope inclination of 2H: 1 V (Horizontal: Vertical) for permanent cut and fill slopes. Permanent slopes should be hydroseeded or otherwise protected from erosion. Temporary erosion control may be necessary until permanent vegetation is established. Satisfactory performance of slopes is strongly affected by drainage and runoff. Care must be taken that drainage is not directed to flow over the slope face. Foundation Considel"ations Seismic Considerations The tectonic setting ofwestem Washington is dominated by the Cascadia Subduction Zone formed by the Juan de Fuca plate subducting beneath the No11h American Plate. This setting leads to intraplate, crustal, and interplate eruthquake sources. Seismic hazards relate to risks to people and damage to property resulting from these three principle earthquake sources. 21905 64" Avenue West Ste 100, Mountlake Terrace, WA 98043 425-771-3304 Fax: 425-771-3549 ~ ZZA-lrerracan Water Distribution System Storage Study Renton, Washi.ngton 81085801 January 19, 2009 Page 7 We understand that the new structures will be designed in accordance with the procedures outlined in the 2006 International Building Code (IBC). Geotechnical eai1hquake engineering input to development of the general design response spectrum of the IBC requires a site class definition, and short period (Ss) and !-second period (S1) spectral acceleration values. The USGS National Seismic Hazard Mapping Project (http://eqhazmaps.usgs.govD computes the 2002 spectral ordinates (5 percent damping) at building periods of 0.2 and 1.0 seconds for ground motions at the project site with a 2 percent probability of cxceedance in 50 years as 1.419g and 0.484g. Therefore, we recommend for the 2006 IBC that S, and S I be assigned values of 1.419g and 0.484g, respectively. Based on the subsurface conditions encountered and published geologic literature, it is our opinion that a site class of C describes the average properties of soils beneath the project site to a depth of 100 feet. This designation describes soils that ai·e considered very dense with a shear wave velocity between 1,200 and 2,500 feet per second, Standard Penetration Test values greater than 50, and an undrained shear strength greater than 2,000 psf. Liquefaction is the phenomenon wherein soil strength is dramatically reduced when subjected to vibration or shaking. Liquefaction generally occurs in saturated, loose sand deposits. It is our opinion, based on the site geology and the subsurface conditions encountered in the test borings, that the risk associated with liquefaction is low. Foundation Support We recommend that the new reservoirs, pump station, rechlorination facility and storm water detention vault be supported on conventional spread footings. The spread footings should be founded on the native dense to very dense sand with varying amounts of silt and gravel, or on a zone of structural fill which extends down to the dense to very dense sand. All structural fill placed below the structures should consist of crushed rock meeting 2008 WSDOT Standard Specification Section 9-03.9(3) for crushed surfacing base course. The crushed rock should be compacted to at least 95 percent of the modified proctor maximum dry density (ASTM D-1557). We recommend that continuous wall and isolated column footings have minimum widths of 1.5 and 2 feet, respectively. Exterior footings should have a minimum depth of embedment of 18 inches below adjacent grade for frost protection. Interior footings should be situated at least 12 inches below the structure floor. Spread footings for the new structures may be propot1ioned using the following allowable bearing values presented as a function of footing width. These values are for static loads and may be increased by one-third for loading conditions which include short-term live loads such as wind or seismic forces. 21905 64 1h Avenue West Ste 100, Mountlake Terrace, WA 98043 425-771-3304 Fax: 425-771-3549 ~ ZZA-lrerracan Footing Width(feet) 1.5 2.0 3.0 4.0 Water Distribution System Storage Study Renton, Washington 81085801 January 19, 2009 Page 8 Allowable Bearing Value(psf) 4,500 5,000 6,000 7,000 We estimate that the post-construction settlement of spread footings, founded as recommended, will be on the order of I inch or less. Most of this settlement is expected to occur rapidly as loads are applied. The soil resistance available to resist lateral foundation loads is a function of the frictional resistance which can develop on the base and the passive resistance which can develop on the face of below-grade elements of the structure as these elements tend to move into the soil. For spread footings founded on the native dense to very dense sand, the allowable frictional resistance may be computed using a friction coefficient of 0.35 applied to the vertical dead-load forces. The allowable passive resistance on the face of footings or other embedded foundation elements may be computed using an equivalent fluid density of250 pounds per cubic foot (triangular distribution) for the on-site soils. Alternatively, passive pressures may be computed using an equivalent fluid density of 300 pounds per cubic foot for compacted structural fill, provided all of the fill soil extending out from the face of the foundation element for a distance at least equal to 2.5 times the embedded depth of the element has been compacted to at least 95 percent of the modified proctor maximum dry density (ASTM D-1557). The above coefficient of friction and passive equivalent fluid density values both include a factor of safety of about 1.5. Ea1ih Anchors We understand that ea1ih anchors might be considered to resist potential seismic overturning for the Phase 4, 4.1 MG standpipe. Several optional anchor systems could be considered including drilled and grouted earth anchors, and helical anchors. In our opinion, drilled and grouted earth anchors would be best suited for the project. We recommend that a minimum diameter of 6 inches be assumed for the drilled anchor holes. A preliminary allowable soil to g1·out bond value of 4.5 kips per foot may be used for the native dense to very dense sand to estimate the anchor length. The anchor should have a minimum bond length of IO feet. A free stressing length of 5 feet should be provided to post- tension the anchors. As a result, soil to grout bond for the upper 5 feet of the anchor should be ignored when computing anchor pullout capacity. The estimated soil to grout bond value of 4.5 kips per foot should be confirmed for the specific installation method used by the contractor by completing an anchor load testing program. We recommend that performance tests be completed on two of the eaiih anchors to be identified by the engineer. Proof tests should be performed on each of the remaining earth 21905 64 1" Avenue West Ste 100, Mountlake Terrace, WA 98043 425-771-3304 Fax: 425-771-3549 ~ ZZA-lrerracan Water Distribution System Storage Study Renton, Washington 81085801 January 19, 2009 Page 9 anchors. The performance and proof tests should be completed in accordance with the procedures outlined in FHWA Geotechnical Engineering Circular No. 4, Ground Anchors and Anchored Systems, June 1999. After the anchors have been load tested, they should be post tensioned to a lock off load which removes all slack from the system and provides a seating load. We recommend that installation and load testing of the earth anchors be monitored by a qualified individual to document the installation procedures, and observe and interpret the load test results. Floor Slab Support We recommend that slab on grade floors be supported on the native dense to very dense sand with varying amounts of silt and gravel, or on a zone of structural fill which extends down to the dense to very dense sand. All structural fill placed below floor slabs should consist of crushed rock meeting 2008 WSDOT Standard Specification Section 9-03.9(3) for crushed surfacing base course. The crushed rock should be compacted to at least 95 percent of the modified proctor maximum dry density (ASTM D-1557). For the below ground rcsc1voirs, stormwater detention vault, and storm drain manholes, the zone of crushed rock should have a minimum thickness of 12 inches of compacted base course to provide uniform supp01t and protect the exposed subgrade soils from disturbance during subsequent construction activities. We estimate that the total settlement of slab on grade floors, designed and constructed as recommended above, will be less than 1 inch. Differential settlements across the structure are anticipated to be less than one-half inch over a distance of 40 feet. Settlements are expected to occur rapidly as loads are applied. We recommend that a representative from our firm observe the condition of the exposed subgrades prior to placing the base course to confirm that the bearing soils are undisturbed and consistent with the recommendations presented in this report. Subgrade Walls Lateral Earth Pressures The lateral soil pressures acting on subgrade walls for below ground reservoirs and storm water detention vault will depend on the nature and density of the soil behind the wall, and the amount of lateral wall movement which can occur as backfill is placed. For walls that are free to yield at the top at least one-thousandth of the height of the wall, soil pressures will be less than if movement is limited by such factors as wall stiffness or bracing. For those portions of the walls that are fully drained as described below, we recommend that yielding walls supporting horizontal backfill be designed using a static equivalent fluid density of 35 pcf(pounds per cubic foot), while nonyielding walls be designed using a static equivalent fluid density of 60 pcf. For 21905 64'h Avenue West Ste 100, Mountlake Terrace, WA 98043 425-771-3304 Fax: 425-771-3549 f4I ZZA-lrerracan Water Distribution System Storage Study Renton, Washington 81085801 January 19, 2009 Page 10 those portions of the walls that are not fully drained, we recommend that yielding walls supporting horizontal backfill be designed using a static equivalent fluid density of 80 pcf (pounds per cubic foot) (20 pcf soil and 60 pcf hydrostatic), while nonyielding walls be designed using a static equivalent fluid density of 90 pcf (30 pcf soil and 60 pcf hydrostatic). Please note that these recommended lateral soil pressures do not include the effects of sloping backfill surfaces or surcharges such as traffic loads or other surface loading. Surcharge effects should be considered as appropriate. We understand that subgrade walls will be designed to resist seismic surcharge loads. For those portions of the walls that are fully drained, we recommend that a uniform seismic surcharge equal to 6H and 14H in pounds per cubic foot(rectangular distribution) be used for yielding walls and nonyielding walls, respectively. For those portions of the walls that are not fully drained, we recommend that a uniform seismic surcharge equal to 3H and 7H in pounds per cubic foot(rectangular distribution) be used for yielding walls and nonyielding walls, respectively. If drainage is provided for subgrade walls, we recommend that the drains consist of a minimum 6-inch diameter, rigid-wall, perforated drainpipe installed at the base of the wall. The perforated drainpipe should be embedded in a zone of coarse sand and gravel containing less than 2 percent fines (Gravel Backfill for Drains per WSDOT Section 9-03.12(4)). The zone of free-draining material should be at least 24 inches wide and extend from near the base of the footing to within one foot of the finished ground surface. The upper one foot of the backfill should consist ofrelatively impervious material to minimize the infiltration of surface runoff into the wall backfill. At appropriate intervals, the drainpipe should be connected to a tightline system leading to a suitable discharge. In addition, cleanouts should be provided for the drainpipe at appropriate intervals. All backfill for subgrade walls should be free of organic material, debris, or other deleterious material. Individual particle sizes should be less than 3 inches in maximum dimension. We recommend that all wall backfill be placed in lifts no greater than IO inches in loose thickness and mechanically compacted to a firm, nonyielding condition. All backfill should be moisture conditioned to within ±2% of optimum moisture content for compaction as determined by the ASTM D 1557 test method (modified proctor) prior to compaction. Backfill for subgrade walls should typically be compacted to between 90 and 92 percent of the modified Proctor maximum dry density. City of Renton compaction requirements should be followed if more stringent. The suitability of soils for use as backfill depends primarily on the gradation and moisture content of the soil when it is placed. As the amount of fines (that soil fraction passing the U.S. No. 200 sieve) increases, soil becomes increasingly sensitive to small changes in 21905 64lh Avenue West Ste 100, Mountlake Terrace, WA 98043 425-771-3304 Fax: 425-771-3549 ~ ZZA-lrerracan Water Distribution System Storage Study Renton, Washington 8 !085801 January 19, 2009 Page 11 moisture content and adequate compaction becomes more difficult, or impossible, to achieve. Generally, soils containing more than about IO percent fines by weight (based on that soil fraction passing the U.S. No. 4 sieve) cannot be compacted to a firm, non-yielding condition when the moisture content is more than a few percent from optimum. The optimum moisture content is that which yields the greatest soil density under a given compactive effo11. The results of our borings indicate that the site soils which will be encountered in project excavations consist primarily of sand and silty sand. These soils contain a significant amount of silt and will therefore be moisture sensitive. In our opinion, the site soils would be suitable for use as wall backfill only if moisture contents are adequately controlled. This may involve drying of over-optimum moisture soils by scarifying or windrowing the excavated material during extended periods of dry weather. In addition, soils which are dry of optimum might have to be moistened through the application of water and thorough blending to facilitate a uniform moisture distribution in the soil prior to compaction. We recommended that all stockpiled soils intended for use as wall backfill be protected from wet conditions with anchored polyethylene sheet plastic strong enough to withstand local wind conditions. We recommended that impotted wall backfill material used for the project consist of "clean", free-draining pit-run sand and gravel meeting the requirements for "Gravel Backfill for Walls", WSDOT 9-03.12(2). It should be noted that the placement of backfill is, in many cases, weather-dependent. Delays due to inclement weather are common, even when using select granular fill. We recommend that eaithwork be scheduled for the drier months, if at all possible. We recommend that a representative from ZZA Terracon be present during the placement of wall backfill to observe the work and perform a representative number of in-place density tests. In this way, the adequacy of the work may be evaluated as backfill placement progresses. Hydrostatic Uplift Hydrostatic uplift should be considered in design of the below ground reservoirs, storm water detention vault, and storm drain manholes if wall drainage is not provided for the full height of the subgrade walls. Hydrostatic uplift may be resisted by a combination of the dead weight of the structure and soil friction resistance acting on the perimeter of the structure. Friction resistance may be computed using a coefficient of friction of0.35 applied to the lateral soil pressures. 21905 64'" Avenue West Ste 100, Mountlake Terrace, WA 98043 425-771-3304 Fax: 425-771-3549 ~ ZZA-lrerracan MOUNT OLIVET SITE SITE CONDITIONS Surface Conditions Water Distribution System Storage Study Renton, Washington 81085801 January 19, 2009 Page 12 The Mount Olivet Site is bounded on the east by a slope which extends up to residential property, and on the nmth, west and south by slopes which extend down to Bronson Way NE and NE 3rd Street. The central po11ion of the site where the new reservoir is planned is relatively level with elevations ranging from 154 to 158 feet. An existing pump building and an existing generator building are located in northwest comer of the relatively level area. Existing vegetation in the relatively level area consists primarily of grass. Various types of ground cover and trees are located on the adjacent slopes. Numerous underground utilities are present at the site. Subsurface Conditions Subsurface conditions at the Mount Olivet Site were explored by completing 3 test borings ( Borings B-7 tluough B-9) at the locations shown on Figure 2, Site and Exploration Plan. Subsurface exploration procedures and the logs of the explorations are presented in Appendix A. Laboratory testing procedures and results are summarized in Appendix B. Borings B-8 and B-9 were located in the vicinity of the new reservoir. The site was mantled by grass and topsoil at both locations. Boring B-8 encountered loose to medium dense silty sand to a depth of 5 feet, underlain by medium dense to very dense sand and silty sand. Boring B-9 encountered medium dense sand and silty sand directly below the grass and topsoil. The medium dense to very dense sand and silty sand was encountered to the maximum depth explored in the borings (34 feet below existing ground surface) Boring B-7 was located in the existing asphalt surfaced parking lot in the no11heast portion of the site. This borings encountered 2 inches of asphalt over medium dense to very dense sand with varying amounts of silt and gravel. Groundwater was observed in Borings B-7 and B-8 at depths of29 and 33 feet, respectively, below the ground surface at the time of drilling. No groundwater was observed in Boring B-9 at the time of drilling. A groundwater observation well was installed in Boring B-8 to monitor groundwater levels following drilling. Groundwater was measmed in this observation well at a depth of28 feet on October 23, 2008. Groundwater levels and soil moisture conditions should be expected to vary throughout the year due to fluctuations in seasonal precipitation, and other on-and off-site factors. 21905 64'" Avenue West Ste 100, Mountlake Terrace, WA 98043 425-771-3304 Fax: 425-771-3549 ~ ZZA-lrerracan CONCLUSIONS AND RECOMMENDATIONS General Water Distribution System Storage Study Rentoll, Washillgton 8108580[ January 19, 2009 Page 13 Based on our site reconnaissance, subsurface exploration, laboratory testing and geotechnica! engineering analyses, we conclude that the project site is suitable for construction of the new 6.9MG reservoir. This conclusion is based, in part, on employing proper design and construction practices to accommodate the conditions discussed below. The following sections of this repo11 contain conclusions and recommendations regarding environmentally critical area considerations, site preparation, temporary cut slopes, permanent slopes, reservoir foundation considerations, and new retaining wall. Environmentally Critical Area Considerations The Mount Olivet property contains and is bounded by steep slope areas. As a result, environmental critical area considerations are discussed in this rep01t for the site. Section 4-3-050 of the City of Renton Municipal Code (RMC) describes the critical areas that are considered by the City of Renton during the development review process. This report addresses the geologic hazards regulated under the RMC including steep slopes, landslide hazards, erosion hazards, seismic hazards, and coal mine hazards. The geologic hazard regulations apply to all nonexempt activities described in Section 4-3-050C5 on sites containing or located within 50 feet of the above hazards. Steep Slopes Section 4-11-010 defines a steep slope as a hillside, or portion thereof. which falls into one of two (2) classes of slope, sensitive or prolected. A protected slope is defined as a hillside, or portion thereof. with an average slope, as identified in the City of Renton Steep Slope Atlas or in a method approved by the City, of forty percent (40%) or greater grade and having a minimum vertical rise of jij/een feet (15?." A sensitive slope is defined as a hillside, or portion thereof. characterized by: (1) an average slope, as identified in the City of Renton Steep Slope Atlas or in a method approved by the City, of twenty jive percent (25%) to less than forty percent (40%); or (2) an average slope, as identified in the City of Renton Steep Slope Atlas or in a method approved by the City, of forty percent (40%) or greater with a vertical rise of less than. fifteen feet (15?, abu{{ing ,111 average slope, as identified in the City of Renron Steep Slope Atlas or in a method approved by the City, o.ftwenty jive percent (25%) to forty percent (40%). This definition excludes engineered retaining walls. 21905 64" Avenue West Ste 100, Mountlake Terrace, WA 98043 425-771-3304 Fax: 425-771-3549 ~ ZZA-lferracan Water Distribution System Storage Study Renton, Washington 81085801 January 19, 2009 Page 14 As shown in Figure 2, the Mount Olivet property slopes downward from east to west to a relatively level area where the new reservoir will be located. From the level area, the site slopes downward to the north, west and south toward Bronson Way NE and NE 3rd Street. The site of the new reservoir is relatively level and would not be defined as a steep slope. Therefore, this area would not be subject to the steep slope provisions of the RMC. Sloped areas to the north, east, south and west of the reservoir site would be classified as protected slopes, having inclinations greater than 40 percent, with local sections up to 0.7H: 1 V (140 percent), and greater than 15 feet in height, As shown in Figure 2, the only proposed development in sloped areas consists of an engineered retaining wall on the southwest side of the new reservoir. The location of the new retaining wall as currently shown would be classified as a protected slope, and subject to code provisions in Section 4-3-0SOJS -Protected Slopes. This Section provides the following: a. Prohibited Development: Development is prohibited on protected slopes. This restriction is not intended to prevent the subdivision or development of property that includes forty percent (40%) or greater slopes on a portion of the site, provided there is enough developable area elsewhere to accommodate building pads. b. Exceptions through Modification: Exceptions to the prohibition may be granted for: i. Filling against the toe of a natural rock wall or rock wall, or protected slope created through mineral and natural resource recovery activities or public 01· private road installation or widening and related transportation improvements, railroad tmck installation or improvement, or public or private utility installation activities pursuant to subsection N2 of this Section, Modifications. ii. Gmding to the extent that it eliminates all or portions of a mound or to allow reconfiguration of protected slopes created through mineral and natural resource recove,y activities or public or private road installation or widening and related transportation improvements, railroad h·ack installation or improvement, or public or private utility installation activities, pursuant to subsection N2 of this Section, Modifications. c. Exceptions through Variance: Exceptions to the prohibition may be granted for construction, reconstruction, additions, and associated accessOIJ' structures of a single family home on an existing legal lot pursuant lo a variance as stated in RMC 4-0-250Bl. d. Exceptions through Waiver: Exceptions to the prohibition may be granted for installation of public utilities which are needed lo protect slope stability, and public road widening where all the following provisions have been demonstrated: i. The utility or road improvement is consistent with the Renton Comprehensive Plan, adopted utility plans, and the Transportation Improvement Program where applicable. ii. Alternative locations haw been determined to be economically orfimctionally infeasible. iii. A geotechnical evaluation indicates that the proposal will not increase the risk of occurrence of a geologic hazard, and measures are identified lo eliminate or reduce risks. 21905 64 1 h Avenue West Ste 100, Mountlake Terrace, WA 98043 425-771-3304 Fax: 425-771-3549 . ~ ZZA-lrerracan Water Distribution System Storage Study Rettton, Washington 81085801 January 19, 2009 Page 15 iv. The plan/or the improvemenl is based on consideralion of the best available science as described in WAC 365-195-905; or where there is an absence of valid scient/fic information, the steps in RMC4-9-250F are followed Where the excepted activities above are allowed, the erosion control measures in subsection J6 of this Section, Sensitive Slopes, Medium, lligh and Ve1y High Landslide Hazards, and High Erosion Hazards, shall also apply. Erosion Hazard Areas RMC Section 4-3-0SOJ!c defines erosion hazards as low or high using the following criteria: i. Low Erosion Hazard (EL): Areas with soils characterized by the Na!urctl Resource Conservation Service (formerly U.S. Soil Conservation Service) as having slight or moderate erosion potential, and that slope less than fifteen percenr (15%). ii. High Erosion Hazard (EH): Areas with soils characterized by the Natural Resource Conservarion Service (formerly U.S. Soil Conservation Service) as having severe or ve1J' severe erosion potential, and that slope more steeply than fifteen percent (15%). According to the National Resource Conservation Service(NRCS), the surficial soils on sloping areas to the north, west and south of the new reservoir site are classified as Alderwood and Kitsap soils, very steep (AkF) for slope inclinations ranging from approximately 25 to 70 percent. The NRCS describes these soils as having a hazard of water erosion that is severe to very severe. Therefore, the proposed retaining wall as currently shown on Figure 2 would be located in an area classified as a high erosion hazard (EH). The new reservoir location and the sloping areas to the east are classified by the NRCS as Everett gravelly sandy loam (EvC and EvD) with slope inclinations ranging from 5 to 15 percent and 15 to 30 percent, respectively. The NRCS describes these soils as having a hazard of water erosion ranging from slight to moderate, and moderate to severe, respectively. The new reservoir site would be located in an area classified as a low erosion hazard (EL). The sloping area to the east of the reservoir site would be classified as a high erosion hazard (EH), In order to pursue developments in high erosion hazard areas, development and design would be subject to the following provisions according to RMC Section 4-3-050J6: 6. Sensitive Slopes -Medium, High and Ve1y High Landslide Hazards -High Erosion Hazards: The following standards apply to development on sensitive slopes, mediwnlhighlve1J' high landslide hazard areas, and high erosion hazard areas: a. Erosion Control Plans: Development applications shall submit erosion control plans consistent with subsection J2 of this Section, Special Studies Required, and chapter 4-8 RMC, Permits and Appeals. b. Conditions of Approval: The Reviewing Official 111ay condition a development proposal to achieve minimal site erosion, including, but not li111ited lo, timing of 21905 64th Avenue West Ste 100, Mountlake Terrace, WA 98043 425-771-3304 Fax: 425-771-3549 ~ ZZA-lrerracan Water Distribution System Storage Study Renton, Washington 81085801 January 19, 2009 Page 16 cons/ruction and vegetation stabilization, sequencing or phasing of cons/ruction, clearing and grading limits, and other measures. Mitigation plans may be required consistent with subsection FB of this Section. c. On-Site Inspections: During cons/ruction, weekly on-site inspections shall be required at the applicant's expense. Weekly reports documenting erosfon control measures shall be required. Landslide Hazard Areas RMC Section 4-3-0SOJ 1 b divides landslide hazards into the following four categories: i. Low Landslide Hazard (LL}: Areas with slopes less than fifteen percent (15%). ii. Medium Landslide Hazard (LM): Areas with slopes between fifteen percent (15%) and forty percent (40%) and underlain by soils that consist largely of sand, gravel or glacial till. iii. High Landslide Hazards (LH): Areas with slopes greater than forty percent (40%), and areas with slopes between fifteen percent (15%) and forty percent ( 40%) and underlain by soils consisting largely of silt and clay. iv. Ve1y High Landslide Hazards {LV): Areas of known mappable landslide deposits. The new reservoir site is relatively level and would therefore be classified as a low landslide hazard (LL). Low landslide hazard areas do not require additional provisions per the RMC. The sloping areas to the n011h, east, south and west of the reservoir site generally have slope inclinations greater than 40 percent but do not contain areas of mappable landslide deposits. Therefore, these sloping areas would be classified as high landslide hazards (LH). The proposed retaining wall as shown in Figure 2 would be located in an area designated as a high landslide hazard. Developments in high landslide hazard areas are subject to the RMC provisions of Section 4-3-050J6 as described above in the Erosion Hazard Areas section of this repot1. Seismic Hazard Areas RMC Section 4-3-0SOJ!d divides seismic hazard areas into the following two categories: i. Low Seismic Hazard (SL): Areas underlain by dense soils or bedrock These soils generally have site coefficients of types SJ or S2, as defined in the Uniform Building Code. ii. High Seismic Hazard (SH): Areas underlain by soft or loose, saturated soils. These soils generally have site coefficients of types SJ or S4, as defined in the Uniform Building Code. 21905 64'" Avenue West Ste 100, Mountlake Terrace, WA 98043 425-771-3304 Fax: 425-771-3549 ~ ZZA-lrerracon Water Distribution System Storage Study Renton, Washington 81085801 January J 9, 2009 Page 17 The Mount Olivet site is generally underlain by medium dense to very dense sand and silty sand. Groundwater was observed at a depth of approximately 25 to 30 feet in dense to very dense soils. According to the Uniform Building Code, the project site would have a site coefficient of S2 for dense soils. RMC Figure 4-3-050Q3d(i) is a map delineating known areas of high seismic hazards. The project site is not shown to be located in an area designated as a high seismic hazard according to the map. Based on the above information, the Mount Olivet site would be classified as a low seismic hazard (SL). Coal Mine Hazard Areas Coal mine hazard areas are divided into three categories by RMC Section 4-3-050Jle: i. Low Coal Mine Hazards (CL): Areas with no known mine workings and no predicted subsidence. While no mines are known in these areas, undocumented mining is known to have occurred. · ii. Medium Coal Mine Hazards (Ci\1): Areas where mine workings are deeper than two hundred feet (200? for steeply dipping seams, or deeper than fifteen (15) times the thickness of the seam or workings for gently dipping seams. These areas may be affected by subsidence. iii. J!igh Coal Mine Hazard (CH): Areas with abandoned and improperly sealed mine openings and areas underlain by mine workings shallower than two hundred feet (200? in depth.for steeply dipping seams, or shallower than.fifteen (15) times the thickness of the seam or workings/or gently dipping seams. These areas may be affected by collapse or other subsidence. According to RMC Figure 4-3-50Q3a(i), the project site is not mapped in an area designated as a moderate or high coal mine hazard. Therefore, the Mount Olivet site would be classified as a low coal mine hazard (CL). Site Preparation Site preparation should include the removal of all vegetation, root mass, organic soils, existing pavements and structures, and any deleterious debris from construction areas including those locations where "structural fill" is to be placed. Any excavations that extend below finish grades should be backfilled with structural fill as outlined subsequently in this report. Boring B-8 encountered a deposit of loose to medium dense silty sand to a depth of 5 feet, underlain by medium dense to very dense sand and silty sand. The loose silty sand should be removed from the limits of the new reservoir and for a minimum distance of 5 feet beyond the perimeter of the ring wall. 21905 641h Avenue West Ste 100, Mountlake Terrace, WA 98043 425-771-3304 Fax: 425-771-3549 ffi ZZA-lrerracon Water Distribution System Storage Study Renton, Washington 81085801 January 19, 2009 Page 18 After site demolition and stripping, we recommend that the new reservoir area be proofrolled and compacted to a firm and unyielding condition in order to achieve a minimum compaction level of 95 percent of the modified Proctor maximum dry density as determined by the ASTM: D-1557 test procedure. Proofrolling should be accomplished with a heavy compactor, loaded double-axle dump truck, or other heavy equipment under the observation of a representative from our firm. Areas where loose surface soils exist should be removed and replaced with structural fill. The need for or advisability of proofrolling due to soil moisture conditions should be dete1mined at the time of construction. We recommend that a representative of our firm observe the soil conditions prior to and during proofrolling to evaluate the suitability of stripped subgrades. Earthwork may be difficult during periods of elevated soil moisture and wet weather due to the moisture sensitive nature of the silty portions of the site soils. Subgrade soils that become disturbed due to elevated moisture conditions should be overexcavated to expose firm, non- yielding, non-organic soils and backfilled with compacted structural fill. We recommend that the earthwork portion of the project be completed during extended periods of dry weather, if possible. If earthwork is completed during the wet season (typically November through May), it may be necessary to take extra precautionary measures to protect subgrade soils. Temporary Cut Slopes We anticipate that construction of the new reservoir may require temporary excavations on the order of 4 to 12 feet below existing adjacent grade. Temporary slope stability is a function of many factors, including the following: I. The presence and abundance of groundwater; 2. The type and density of the various soil strata; 3. The depth of cut; 4. Surcharge loading adjacent to the excavation; and 5. The length of time the excavation remains open. It is exceedingly difficult under the variable circumstances to pre-establish a safe and "maintenance-free" temporary cut slope angle. Therefore, it should be the responsibility of the contractor to maintain safe slope configurations since the contractor is continuously at the job site, able to observe the nature and condition of the cut slopes, and able to monitor the subsurface materials and groundwater conditions encountered. It may be necessary to drape temporary slopes with plastic or to otherwise protect the slopes from the elements and minimize sloughing and erosion. We do not recommend vertical slopes or cuts deeper than 4 feet if worker access is necessary. The cuts should be adequately sloped or supported to prevent injury to personnel from local sloughing and spalling. The excavation should conform to applicable Federal, State, and local regulations. Most of the soils which will be exposed in project excavations are consistent with the criteria for Type C soils presented in Chapter 296-155, Part N, Excavation Trenching and 21905 641h Avenue West Ste 100, Mountlake Terrace, WA 98043 425-771-3304 Fax: 425-771-3549 ~ ZZA-lrerracon Water Distribution System Storage Study Renton, Washington 8!085801 January 19, 2009 Page 19 Shoring, of the Washington Administrative Code (WAC). Consequently, we recommend that maximum temporary slope inclinations of I.SH: 1 V be considered for preliminary planning purposes. Permanent Slopes We recommend a maximum slope inclination of2H:1V (Horizontal:Vertical) for permanent cut and fill slopes. Permanent slopes should be hydroseeded or otherwise protected from erosion. Temporary erosion control may be necessary until permanent vegetation is established. Satisfactory performance of slopes is strongly affected by drainage and runoff. Care must be taken that drainage is not directed to flow over the slope face. Reservoir Foundation Considerations Seismic Considerations The tectonic setting of western Washington is dominated by the Cascadia Subduction Zone formed by the Juan de Fuca plate subducting beneath the North American Plate. This setting leads to intraplate, crustal, and intetplate eatthquake sources. Seismic hazards relate to risks to people and damage to property resulting from these three principle earthquake sources. We understand that the new reservoir will be designed in accordance with the procedures outlined in the 2006 International Building Code (!BC). Geotechnical eat1hquake engineering input to development of the general design response spectrum of the !BC requires a site class definition, and shot1 period (Ss) and I-second period (S1) spectral acceleration values. The USGS National Seismic Hazard Mapping Project (http://cqhazmaps.usgs.govD computes the 2002 spectral ordinates (5 percent damping) at building periods of 0.2 and 1.0 seconds for ground motions at the project site with a 2 percent probability of exceedance in 50 years as 1.424g and 0.487g. Therefore, we recommend for the 2006 IBC that S, and S 1 be assigned values of J .424g and 0.487g, respectively. Based on the subsurface conditions encountered and published geologic literature, it is our opinion that a site class of D describes the average properties of soils beneath the project site to a depth of 100 feet. This designation describes soils that are considered stiff with a shear wave velocity between 600 and 1,200 feet per second, Standard Penetration Test values between 15 and 50, and an undrained shear strength between 1,000 and 2,000 psf. Liquefaction is the phenomenon wherein soil strength is dramatically reduced when subjected to vibration or shaking. Liquefaction generally occurs in saturated, loose sand deposits. It is our opinion, based on the site geology and the subsurface conditions encountered in the test borings, that the risk associated with liquefaction is low. 21905 64\h Avenue West Ste 1001 Mountlake Terrace, WA 98043 425-771-3304 Fax: 425-771,3549 if4I ZZA-lrerracon Setbacks From Adjacent Slopes Water Distribution System Storage Study Renton, Washington 81085801 January 19, 2009 Page 20 A slope which extends up to residential prope11y is located in the eastern portion of the site. This slope appears to be inclined at approximately 2H:IV to 3H:1 V(Horizontal to Vertical), and on the order of 40 to SO feet high. The slope is fenced and heavily vegetated. No reconnaissance or subsurface explorations were completed for this portion of the site during the current study. As a result, it is not possible to evaluate the stability of the slope with respect to development of the reservoir site. However, we recommend that a minimum setback of 25 feet be assumed from the toe of the slope to the new reservoir for preliminary planning purposes. This setback should be measured from the toe of the portion of the slope which is inclined at 40%, or steeper. Slopes which extend down to Bronson Way NE and NE 3rd Street are located in the no11hern, western and southern portions of the site. These slopes are typically inclined at 1 H: IV to 2H: IV and range up to SO feet high. A formal stability analyses of these slopes was not completed. However, based on the results of a site reconnaissance of the slopes and the subsurface conditions indicated by the results of Borings B-8 and B-9, we recommend that a minimum setback of25 feet be assumed from the crest of the slope to the new reservoir for preliminary planning purposes. This setback should be measured from the crest of the portion of the slope which is inclined at 40%, or steeper. The new retaining wall on the southwest side of the new reservoir will likely be located within the reconunended setback distance as shown in Figure 2. In our opinion, it should be possible to develop a design for this retaining wall which can adequately mitigate the potential effects of slope stability. Foundation Support We understand that the reservoir will be supp011ed on a perimeter ring wall foundation with interior footings supporting the roof. The tank floor will be at about elevation I 52 feet. We understand that the base of the ring wall footing and interior footings will be at about elevation 146 and 148 feet, respectively. Preparation of the reservoir pad should include demolition of the existing reservoir including all existing foundation elements and piping. All strnctural fill placed below the reservoir should consist of crnshed rock meeting 2008 WSDOT Standard Specification Section 9-03.9(3) for crushed surfacing base course. The crushed rock should be compacted to at least 95 percent of the modified proctor maximum dry density (ASTM D-1557). The ring wall and interior spread footings should be founded on the native medium dense to very dense sand and silty sand which is expected to be present at the base of the footing excavations. We recommend that the footings have a minimum width of 2 feet. The ring wall 21905 641h Avenue West Ste 100, Mountlake Terrace, WA 98043 425-771-3304 Fax: 425-771-3549 ~ ZZA-lrerracan Water Distribution System Storage Study Renton, Washington 81085801 J anua,y I 9, 2009 Page 21 footing should have a minimum depth of embedment of 18 inches below adjacent grade for frost protection. Interior footings should be situated at least 12 inches below the reservoir floor. The spread footings may be proportioned using the following allowable bearing values presented as a function of footing width. These values are for static loads and may be increased by one-third for loading conditions which include shott-term live loads such as wind or seismic forces. Footing Widthffeet) 1.5 2.0 3.0 4.0 Allowable Bearing Value(psQ 4,500 3,000 4,000 5,000 We estimate that the post-construction settlement of the spread footings, founded as recommended, will be on the order of I inch or less. Most of this settlement is expected to occur rapidly as loads are applied. The soil resistance available to resist lateral foundation loads is a function of the frictional resistance which can develop on the base and the passive resistance which can develop on the face of below-grade elements of the structure as these elements tend to move into the soil. For spread footings founded on the native medium dense to very dense sand and silty sand, the allowable frictional resistance may be computed using a friction coefficient of 0.35 applied to the vertical dead-load forces. The allowable passive resistance on the face of footings or other embedded foundation elements may be computed using an equivalent fluid density of 250 pounds per cubic foot (triangular distribution) for the on-site soils. Alternatively, passive pressures may be computed using an equivalent fluid density of 300 pounds per cubic foot for compacted structural fill, provided all of the fill soil extending out from the face of the foundation element for a distance at least equal to 2.5 times the embedded depth of the element has been compacted to at least 95 percent of the modified proctor maximum dry density (ASTM D-1557). The above coefficient of friction and passive equivalent fluid density values both include a factor of safety of about 1.5. Eaith Anchors We understand that earth anchors might be considered to resist potential seismic overturning of the tank. Several optional anchor systems could be considered including drilled and grouted eaith anchors, and helical anchors. In our opinion, drilled and grouted earth anchors would be best suited for the project. We recommend that a minimum diameter of 6 inches be assumed for the drilled anchor holes. A preliminary allowable soil to grout bond value of3.5 kips per foot may be used for the native medium dense sand and silty sand to estimate the anchor length. The anchor should have 21905 64 1 h Avenue West Ste 100, Mountlake Terrace, WA 98043 425-771-3304 Fax: 425-771-3549 ~ ZZA-lrerracan Water Distribution System Storage Study Renton, Washfogton 8!085801 January 19, 2009 Page22 a minimum bond length of 10 feet. A free stressing length of 5 feet should be provided to post- tension the anchors. As a result, soil to grout bond for the upper S feet of the anchor should be ignored when computing anchor pullout capacity. The estimated soil to grout.bond value of3.5 kips per foot should be confirmed for the specific installation method used by the contractor by completing an anchor load testing program. We recommend that performance tests be completed on two of the earth anchors to be identified by the engineer. Proof tests should be performed on each of the remaining earth anchors. The performance and proof tests should be completed in accordance with the procedures outlined in FHWA Geotechnical Engineering Circular No. 4, Ground Anchors and Anchored Systems, June 1999. After the anchors have been load tested, they should be post tensioned to a lock off load which removes all slack from the system and provides a seating load. We recommend that installation and load testing of the earth anchors be monitored by a qualified individual to document the installation procedures, and observe and interpret the load test results. Reservoir Floor We recommend that the reservoir floor be supported on the native medium dense to dense sand and silty sand, or on a zone of structural fill which extends down to the medium dense to dense sand and silty sand. All structural fill placed below the tank floor should consist of crushed rock meeting 2008 WSDOT Standard Specification Section 9-03.9(3) fo1· crushed surfacing base course. The crushed rock should be compacted to at least 95 percent of the modified proctor maximum dry density (ASTM D-1557). We recommend that the zone of crushed rock have a minimum thickness of 12 inches to provide uniform suppo1t and protect the exposed subgrade soils from disturbance during subsequent constrnction activities. We estimate that the total settlement of the reservoir floor under the water load will be on the order of 2 to 3 inches at the center of the tank and 1 to I Y2 inches at the tank perimeter. Settlements are expected to occur rapidly as loads are applied. New Retaining Wall We understand that a new retaining wall might be required on the southwest side of the new reservoir. This wall would retain fill placed to provide relatively level access to the area. Depending on the final height of the wall and its proximity to the top of the adjacent slope, a variety of different wall types could be utilized at this location. The following common wall types might be considered. ZZA Terracon is available to provide additional geotechnical infotmation regarding the preferred wall type. 21905 641 • Avenue West Ste 1001 Mountlake Terrace, WA 98043 425-771-3304 Fax: 425-771-3549 ~ZZA-lrerracon Water Distribution System Storage Study Renton, Washington 81085801 January 19, 2009 Page23 • Rockery • Ecology block wall • Mechanically stabilized earth (MSE) wall • Conventional reinforced concrete wall USE OF THIS REPORT We have prepared this report for use by HDR Engineering and the City of Renton for the City of Renton Water Distribution System Storage Study. The data and report may be used for planning and estimating purposes, but our report, conclusions and interpretations should not be construed as a warranty of the subsurface conditions. If there are any changes in the grades, locations, configurations of types of facilities to be constrncted, the conclusions and recommendations presented in this report might not be fully applicable. If such changes are made, we should be given the opportunity to review our conclusions and recommendations and to provide written modification or verification of these recommendations. When the design has been finalized, our firm should review the final design drawings and specifications to see that our recommendations have been interpreted and implemented as intended. There are possible variations in subsurface conditions across the site and also with time. A contingency for unexpected conditions should be included in the project budget and schedule. Sufficient monitoring, testing and consultation should be provided by our firm during con- struction to confirm that the conditions encountered are consistent with those indicated by the explorations, to provide recommendations for design changes should the conditions revealed during the work differ from those anticipated, and to evaluate whether or not earihwork and foundation installation activities comply with the contract plans and specifications. Within the limitations of scope, schedule and budget, our services have been executed in accordance with generally accepted practices in this area at the time the report was prepared. No warranty or other conditions, express or implied, should be understood. The conclusions and recommendations in this report should be applied in their entirety. lfthere are any questions concerning the report or ifwe can provide additional service, please contact us. Respectfully submitted, 1/1'1/01 "-...) (YV-<"", i3 S'i"-~ James B. Thompson, Ph.D., PE Senior Principal tlake Terrace, WA 98043 425-771-3304 Fax: 425-771-3549 V -r - I I I I I I d .---,,, I "·"""''"-··1--1-',, ......... I ---'L ~ ' -__ /,, I -I" II -=~~~oi,~ -- ~ HDl,S[ Et n:• (1~UT/ Olm..IT) TOD'.. RES(~;,J-,!l '·'--~ I I ___ _J 'l,, -=-~~-- LEGEND: ' " 1~\ '~ I I I I I I),,= I I I I I ! I , IS ~ ~ EX. 1.5 M.G. RESERVOIR ""'" I \.m PROPOSED 7 .9 MG RESERVOIR (PHASE 2) OVERFLOW = 445.5 FlNISHEO FLOOR = 425.0 \ I 8-51 s,;. : ;-·;){ r ~ --~ ·c=" ::i::,._ -_ j ~/ -J ---'-•;;; c.•- J·.-.,',"~' ' J ---. I I I I I I Proj£,d!kv; l)T,1()8y. S8-1 BORING NUMBER AND """"'" APPROXIMATE LOCATION ,WMd&(. JBT RMS JBT JBT ~ f'lqt'l:tNo 31085801 ,,,. AS SHOWN ""~ ,~u .. ""' IOl:>2/03 _...._-:s---........-Z RESIOENCES WATER SYSTe.t ' ' -• _ --_ _ 60 _, 30 -·-0 12· WATER TO RETIR8.IENJ~ - , -•---W---•~w~I . ~ ~ .-~,AL\ FEET ~ET(R VAULt PROPOSED 8.0 MG RESERVOIR (PHASE 1) OVERFLOW = 445.5 FINISHED FLOOR = 425.0 l~DRAJN ~ -----------=======~====------------- --IE;.. 415.9, ~INT[Rt-W. "'-DRAIN -~E ~ ~~4:0:t SEPARATION WALL 8-2 ~~~~ -~J ~ -. " I ~a~ -60 -- j ~-------- • \ C BASEMAP PROVIDED BY HOR ENGINEERING INC. AND MODIFIE~A-TERRACON ~ ZZA-lrerraccn SITE ANO EXPLORATION PLAN l"G. "'I WATER DISTRIBUTION SYSTEM STORAGE STUDY Consulting EngineetS and Scientisls Highlands Site 11m6"!1~W.S1e-lOO l.lwn.Wlf~ace,l'.A9!0U Pttl"ffl7J1~ FA(,ll5ln1~ _ Renton, Washington 1 ----- ,,, ' ', '-. / ' ' / / ' . / ',.','(' -;, \' . \ ,\' .\ '\ .\' \,' / <{> LEGEND: ~B-1 : ' . / // 124 / ·~. -1z?. __ , / / / / / / /'. / \ / l.;,o '"'• > / / ( \ \- , \ \EO _: \ \ \ ,-.,<o // ,,,b \. .\ \ / / \ , ,,b,. \ ,,1.,·' ;-... ' ·.'..' ','- '> ·, '· ' ' ' . . ',' / ' 'PROPOSED. 'RESERVOIR \ FOV,~,?,ATIAN, ', /' /' <>., i t, %, ~ ~ -,_ / .· ,• C8 l90~4 -P.?£ I R£:!J4.62 [ OOT; 13~.77 i;· CO..'iC,s'II' f ' '""a'"" S[ , /, ,!00]1'5 / /-,,,,-· ,.,.,, \001 '"';' '"""71 --~ / , / , ·' sD / sm<f« 01 ,.(., m, ~ , /~ / ) ''b"''",./~"''" I , ~/ R£1,JW15·c~c~ ~~'« ' ', r 'amoas<",e,ce ''"''~i,a·coscSE , ,;' / '--~----'"" ,•co,c, "' \ _L_ ,_ '""_ -· ~ , . --··'"" , -----I' ~-8 (lL'O/'IC'!) -------------. -·"--,;hi -·--· --. . "" , " '"",.., -------. . . I 'UGC Of -~~ -1,~"·"'"'"~-'~·= ,n•«o"" " -.-• _J:if(,; ~ /::'.",,,,. ~--' ' ' / --'S' : ~·.,·.,., ~--~ -_?CA"' // --- _-...;: . /,RELOCATE tX. QHP . ~ ·:, ,g i / / i '\ -~ i'" '-'. ~,~.Ci\'' ,_', ",,','\. '· ,' '' \<,>\'"-~ < ~ ,,,Y' ; , , :>·~{~E-~:is -N~;WAlL~-, , ,, 10,\' ',,?f\:,' ' _'(AL~'!:.QNi(. W£ VH /l:f.:154.11 .: T~ ~JT: 15056 40/ /;ii a 40 r· -...J j SCALE 'tN FEET ·-'-N / ~B-7 // / ./ / / / . "· ' \,: ; }.{ PROPOSED, , , .J%1· , , · .· · · , '-..._ '-105 '$,B-8' tt>'*'1.11-it'i<. BORING NUMBER AND (Pf,AS • RESERVOIR · \ ' . . , ,; RE. ' · . ·, ' FIN~H~ OVERFLOW l6 · 2 9 MG), .. ' ' , ,MoV_E EX,: fENCE' D FLOOR 09.50 ' , . . · DIAMETER _ -, 152.00 \' , f--1 • -_140.00· \'-. \ '-.:o.. I -__j ""'"" 0!""'113,: ~13'(. APPROXIMATE LOCATION .......,,, ··;c1t-~ vAlJ.r. .'Rf~Ti»l'~RID.ElJ£"; ·. 'Rf: 15~ . .a ... ·~ :~ ~:r:;~~~?-- ~01.0r,\tT, )~V)j) %. I>' "--'. ·,~., ~ ~ % <;. ... V. 'ii ~ -,/i ~ 11 %. ··"'J.g_mHAUi.l" <S' ~ '·~---. ·. it~~~ii~:i· . ,::,, <·.·. · .. :·-.. <: -.··-.' ·, .. ~:·-··,. <' -·.-. ~-:. · ,oBASEMAP PROVIDE_D _BY HOR ENGINEERING INC. AND MODIFIED BY ZZA-TERRACON JST _ .. 81085801 ~ ZZA-lrerracon SITE AND EXPLORATION PLAN -~ -WATER DISTRIBUTION SYSTEM STORAGE STUDY RMS AS SHOWN ~lb ConsulUng Eng·neers and Scientists Mt. Olivet Site JBT Fio2.dwo -11ro5.6"1hAWR!<!W~S\!ol00 ~Ten-.w.\9000 Renton, Washington JBT 10ml08 P'H.(415)771.:rot ~A'<.(4251111·3549" --·- APPENDIX A FIELD EXPLORATION PROCEDURES AND LOGS APPENDIX A FIELD EXl'LORA TION PROCEDURES AND LOGS The field exploration for this project consisted of completing 6 borings at the Highlands Site on October 13 and 14, 2008, and 3 borings at the Mount Olivet Site on October 15, 2008. Approximate exploration locations are shown on the Site and Exploration Plans, Figure 1 and 2. Exploration locations were determined by measuring distances from existing site features with a fiberglass tape relative to a topographic map of the site provided by HDR Engineering, Inc. As such, the exploration locations should be considered accurate only to the degree implied by the measurement method. The approximate ground surface elevation at each exploration location was determined by interpolating from the information provided on the topographic plan. The following sections describe our procedures associated with the exploration. Descriptive logs of the explorations are presented in this appendix. The exploratory borings were advanced with a hollow stem auger, using a truck- mounted drill rig operated by an independent drilling company working under subcontract to our firm. A geotechnical engineer from our firm continuously observed the borings, logged the subsurface conditions encountered, and obtained representative soil samples. All samples were stored in moisture-tight containers and transported to our laboratory for further visual classification and testing. Except where an observation well was installed in the boring, the borehole was backfilled with soil cuttings after completion of drilling, and the surface was patched with either bentonite clay or concrete. Throughout the drilling operation, soil samples were obtained at 2.5-to 5-foot depth intervals by means of the Standard Penetration Test (ASTM: D-1586). This testing and sampling procedure consists of driving a standard 2-inch outside diameter steel split spoon sampler 18 inches into the soil with a 140-pound hammer free falling 30 inches. The number of blows required to drive the sampler through each 6-inch interval is recorded, and the total number of blows struck during the final 12 inches is recorded as the Standard Penetration Resistance, or "blow count" (N value). If a total of 50 blows are shuck within any 6-inch interval, the driving is stopped and the blow count is recorded as 50 blows for the actual penetration distance. The resulting Standard Penetration Resistance values indicate the relative density of granular soils and the relative consistency of cohesive soils. The enclosed boring logs describe the vertical sequence of soils and materials encountered in each boring, based primarily upon our field classifications and supported by our subsequent laboratory examination and testing. Where a soil contact was observed to be gradational, our logs indicate the average contact depth. Where a soil type changed between sample intervals, we inferred the contact depth. Our logs also graphically indicate the blow count, sample type, sample number, and approximate depth of each soil sample obtained from the boring, as well as the laboratory tests performed on these soil samples. If groundwater was encountered in a borehole, the approximate groundwater depth, and date of observation, are depicted on the log. Groundwater depth estimates are typically based on the moisture content of soil samples, the wetted portion of the drilling rods, the water level measured in the borehole after the auger has been extracted, or th.rough the use of an observation well. Groundwater observation wells were installed at three of the boring locations (Borings B-1, B-4 and B-5) at the Highlands Site and one of the boring locations (Boring B-8) at the Mount Olivet Site. Each well consisted of a length of slotted 2-inch PVC pipe placed in the bottom of the borehole. A blank PVC riser extended from the lower slotted section to the ground surface. Washed silica sand was utilized to backfill the annular space between the slotted interval and the borehole to allow entry of water into the well, while a mixture of bentonite clay and soil cuttings was used to backfill around the blank riser. A concrete surface seal and locking metal monument cover were placed at the surface. The groundwater level measured within each observation well subsequent to completion of drilling is indicated by a triangular symbol on the logs, along with the date of measurement. This information is also discussed in the text. LOG OF BORING NO. B-1 Pafle 1 of 2 CLIENT HDR Enflineerinfl, Inc. SITE Highlands Site PROJECT City of Renton ·-r---------·. Renton, Washington Water Distribution System Storage Study SAMPCES --TESTS ---- WELL (!) DESCRIPTION DETAIL _J .~ 0 ~ 0 m > "' _J ::E ¢! ,__. 0 4' a: .... Well ID = APQ-800 ,-a: w a:m 2 r ~ "' w 6 ":¥! n. BOREHOLE DIA.: 6 in "' m w ~~ :, ~ WELL DIA.: 1 In 0 ::E n. 0 f-0 ,- w "' :, ~ w n. _J ~8 ~8. (!) GROUND SURFACE ELEV.: 432 ft 0 :, z a: o,m i:=; Grass over 3 inches Topsoil over SIL TY - SANO, trace gravel, light brown, medium - 2 dense, damp 430 - .·. :-SIL TY SAND, with gravel, gray-brown -SM S-1 SPl 52 9 with very slight Iron oxide staining, very --· ... :. dense, moist -5- ._._c:-. --. _.:. -- :-grades to trace gravel, no staining -SM S-2 SPl 5014" = - 10-.-.··-: --- \1. - grades to gravelly, with tan silt pocket -SM S-3 ~p 50/5" 10 L -- kl - 15- :-r.. -- 1-: -- :I· SM 5.4 $Pl 56 -----:·.-. grades to moist lo wet - -20--.· .. -. - 1-.. -- .. · grades to with silt -SP S-5 SPl 50/5" 5 "'" - 25----,.·. grades to wet •. •. -SP S-6 SPl 50/5" -SM ·>==·:· .. -,:·.=·:·. 30-::= :.· - :-~:\. -- · .-. :. 32.5 399.5 -: --Continued Next Paae The stratification lines represent the approximate boundary lines between soil and rock types: In-situ, lhe transition may be gradual. WATER LEVEL OBSERVATIONS, ft BzzA.:Jrerracon BORING STARTED 10-13-08 WL 'l-1.1: BORING COMPLETED 10-13-08 WL !l-,~ 21905 64th Avenue West, Ste. 100 RIG TRUCK I co. EDI Mountlake Terrace, WA 98043 --·-· WL V: {425) 771-3304 F: (425) 771-3549 LOGGED RMS\ JOB# 81085801 b " z 0 I LOG OF BORING NO. B-1 Paae 2 of 2 -- CLIENT HOR Englneerina, Inc. SITE Highlands Site PROJECT City of Renton Renton, W!ishlnaton Water Distribution System Storaae Study SAMPLES TESTS WELL DESCRIPTION DETAIL ..., .S (!) 0 *-~ g Ol ~ 0 ¢i ! "' ,-: t:: « ~ «z r t w ~~ z 0. (/) a, w 0 I!!~ :, & 0. 0 :;; 0. 0 li:9 >-w (/) :, ~ w 18 n (!) 0 :, z « (/) Ol -,--_:.·t:: .... · SP ·: ·-t= ·.-: -S-7 SP 50/6" 6 ,":t= .·. _ vm -· -I:.-~•::.• 35-- t= :·. - ,' f--•' - \~\ - -SP S-8 SPT ··~ -· 74 grades to with gravel -SM 39.5 392.5 ::::J;~-- Boring completed at 39.5 feet on 10/13/08. No groundwater observed while drilling. No groundwater observed In piezometer on 10/23/08. The stratification lines represent the approximate boundary tines between soil and rock types: In-situ, the transition may be gradual. WATER LEVEL OBSERVATIONS, ft NzzA.:Jrerracon BORING STARTED 10-13-08 WL '¥-1:i BORING COMPLETED 10-13-08 WL :l. 1:¥. 21905 64th Avenue West. Ste. 100 RIG TRUCK I co. EDI WL Mountlake Terrace, WA 98043 RMS IJOB# 81085801 V: (425) 771-3304 F: (425) 771-3549 LOGGED LOG OF BORING NO. B-2 Page 1 of 2 CLIENT HOR Englneerlna, Inc. ---~··-~-~- SITE Highlands Site PROJECT City of Renton Renton, Washington Water Distribution System Storaae Studv SAMPLES TESTS -- (!) 6 .5 '#. ~ g DESCRIPTION 00 >' () "' :;; 0:: !: o::~ !:: >-0:: w 'i: ~ ff) w 6 ';'~ z 0. i'l II) w ~I< :, ~ :;; "-() !;:g >- Approx. Surface Elev.: 426 ft w ff) :, ~ w s:8 O:'t) (!) 0 :, z 0:: (f)ll) 0 C. Grass over 3 inches Topsoil over SIL TY -- SAND, trace gravel, tight brown, loose to -- . .;: 2.5 medium dense, damp 423.5 - Ii SIL TY SAND, trace gravel, gray-b-rown, -SM S-1 SPT 81 7 very dense, damp - :.· --- -_.1.-- 5-1.-.1:--ii --r·.:--:: grades to gravelly, moist -SM S-2 SPT 50/3" -: -- ; } 10--=- --- -SM S-3 SPT 50/6" 6 ___J -GS --_._. - -- 15----- grades to trace iron oxide staining -SM S-4 SP1 50/5" -1.-:·.·-:. - 20----- grades to trace slit with silty sand lenses, -SP S-5 SPT 50/6" 11 moist to wet ---.. - - 25- -- grades to trace gravel -SP S-6 3P 50/5" - - 30---- •. ·:_ :-: 32.5 393.5 -- Continued Next Page The stratification lines represent the approximate boundary lines between soil and rock types: in·silu, the transition may be gradual. WATER LEVEL OBSERVATIONS, ft llizzA.:Jrerracon BORING STARTED 10-13-08 WL 'l ll'. BORING COMPLETED 10-13-08 WL 'l 1-l' 21905 64th Avenue West, Ste. 100 RIG TRUCK\co. EDI WL Mountlal<e Te,race, WA 98043 RMS \JOB# V: (425) 771-3304 F: (425) 771-3549 LOGGED 81085801 LOG OF BORING NO. B-2 Paae 2 of 2 CLIENT HDR Enalneerlna, Inc. -- SITE Highlands Site PROJECT City of Renton Renton, Washlni:iton Water Distribution Svstem Storage Studv SAMPLES TESTS (!) ..J .~ 0 ~ ~ g DESCRIPTION a, > (.l "' ~ "' "' "'~ f-"' ~ z :i: ~ UJ ';~ n. g "' w ~~ :, ~ :. ~ ~ li:S >-w :, ~8 °''tl (!) 0 :, 2 "' <l)al 0 C. ::i grades to gravelly, trace cobbles, dense -SP S-7 SPl 48 5 - 1-: - 35- Ji --- - grades to very dense -SP S-8 SPl 50/5.5' 1:-39 387 - Boring completed at 39 feet on 10/13/08. No groundwater observed while drilling. The stratification lines represent the approximate boundary lines between soil and rock types: in-situ, the transition may be gradual. WATER LEVEL OBSERVATIONS, fl l\lzzA.:Jrerracon BORING STARTED 10-13-08 WL '¥. 1:i -·--- BORING COMPLETED 10-13-08 j_" ----- 1-1'-TRUCK I co. WL 21905 64th Avenue West, Sle. 100 RIG EDI Mountlake Terrace, WA 98043 WL V: (425) 771-3304 F: (425) 771-3549 LOGGED RMS I JOB# 81085801 LOG OF BORING NO. B-3 Page 1 of 2 CLIENT HDR Englneerina, Inc. ----- SITE Highlands Site PROJECT City of Renton Renton, Washington __ Water Distribution System Storage Study SAMPLES TESTS C, -' -~ 0 ~ 0 DESCRIPTION a, ,: * -' :. "' 0 "' 11'. >-' t: >-0:: ~ ffi~ z 'i: :i V) w ";'~ "-I-V) a, LU :::, ~ "-0 :. ~ 0 li:'3 ~z >- Approx. Surface Elev.: 429 ft w V) :::, w :s:8 O::'t; C, D :::, z 0:: <1)0, Do_ :_:_\·:: Grass over 3" Topsoil over SILTY SAND, - trace gravel, light brown, loose to medium - .-2 ,-----ill - dense, damp - SIL TY SAND, with gravel,--gray-brown, -SM S-1 SP1 46 7 dense, damp - -f--· ---5- - :·-1:--- ·-:· - -·--.1·. grades to gravelly, very dense. moist -SP S-2 SP1 55 -SM ------ -::-- :i-r 10- i-'· --k: - -SM S-3 SP 50/5" 8 - 15----- :- : .. _ .. _. grades to with gravel SM S-4 SPl 50/6" - - 20- - 'c -- grades to gravelly, with silt -SP S-5 SP 50/4" 5 _ <>IYI - 25-.. .. _-,: - -- :-grades to trace sill -= si> S-6 SP 50/6" -- 30--= - .... . 32.5 396.5 - Continued Next Paae The stratification lines represent the approximate boundary lines between soil and rock types: in·silu, the transition may be gradual. WATER LEVEL OBSERVATIONS, fl PzzA.:Jrerracon BORING STARTED 10-13-08 WL 'St. -~~- BORING COMPLETED 10-13-08 -~·· 51-·-. ----.. TRUCK\CO. --- WL 21905 64th Avenue West, Ste. 100 RIG -~ -------Mountlake Terrace, WA 98043 - WL V: (425) 771-3304 F: (425) 771-3549 LOGGED RMS !JOB# 81085801 LOG OF BORING NO. B-3 Paae 2 of 2 CLIENT HOR Enalneering, Inc. SITE Highlands Site PROJECT City of Renton Renton, Washington Water Distribution Svstem Storage Studv SAMPLES TESTS g ...J .~ 0 ;f. ~ DESCRIPTION "' ~ ~ oi f oi >--!:: O'. ~ ll'.tiJ z I :c w ';'~ a. >-(/) "' w 11:!!z ::::, ~ a. '-' ::; a. '-' >-0 >-w (/) ::::, ~ w a. ...J is ~8. (!) Q ::::, z O'. (!)ID -· grades to trace gravel, trace silt lenses -SP S-7 SPl 80 6 - - 35~ - - -- 38.5 grades lo gravelly 390.5 -SP S-8 SPl 50/5" Boring completed at 38.5 feet on 10/13/08. No groundwater observed while drilling. The stratification lines represent the approximate boundary llnes between soll and rock types: in•silu, the transition may be grndual. WATER LEVEL OBSERVATIONS, ft llzzA.:Jrerracon BORING STARTED 10-13-08 WL '¥. J.!: BORING COMPLETED 10-13-08 ------- 'l 1v. TRUCK I co. WL 21905 64th Avenue West, Ste. 100 RIG EDI WL Mountlake Terrace, WA 98043 RMSI JOB# V: (425) 771-3304 F: (425) 771-3549 LOGGED 81085801 LOG OF BORING NO. B-4 Page 1 of 2 CLIENT .. --~--- HOR Engineering, Inc. SITE Highlands Site PROJECT City of Renton -------· Renton, Washington -·· Water Distribution System Storage Study -~~l§_S_ TESTS WEll 0 DESCRIPTION DETAll ..., .S 0 ,I! ~ 0 (I) ,: ..., :. ¢! ~ 0 ¢! a: I- Well ID= >-a: i z J: :r' "' w ';~ a:~ Q. BOREHOlE DIA.: 6 In 6: "' (I) w l!!z ::, r2 WEll DIA.: 1 In 0 :. Q. 0 1-0 h w "' ::, ~ w a. .... ~8 0 GROUND SURFACE ElEV.: 424 ft 0 :, z a: V)(O 0 Q. Grass over 3" Topsoil over SIL TY SAND, trace gravel, light brown, medium dense, - damp -:·: -SM S-1 SP 21 7 - 4 420 - ·:· SILTY SAND, trace gravel, gray-brown, - ·.::.1:-very dense, damp 5--:'::·1-: - -:·:·1 -- ':i1-: -SM S-2 SPl 5016" ··'.[:. --r· 10-)\. - - [:. - JI - [:. grades to with gravel =~ S-3 $Pl 5015.5' 7 GS J:!-: -- 15-· - -- - grades to moist -SM S-4 SPl 66 - - 20-- - - grades lo with silt -SP S-5 SPl 73 10 -SM - .. 25- --. I· - SPl 50/4'' ---~ ::.:·r-::.:· -SP S-6 -:·.j~·:\· -~ ... -.. ~:·. 30- .:.-~ .. ·. - ·::·t= ::.'· - - :-, 32.5 391.5 · ~-· -.~. - Continued Next Page The stratificalion lines represent the approxlmato boundary lines between soil and ,ock types: in.situ, the transition may be gradual. WATER LEVEL OBSERVATIONS, ft illzzA.:Jrerracon BORING STARTED 10-14-08 WL 'SJ. I,: BORING COMPLETED 10-14-08 ---'!. I~ TRUCK I CO. WL 21905 641h Avenue West, Ste. 100 RIG EDI WL Mountlake Terrace, WA 98043 RMS !JOB# V: (425) 771-3304 F: (425) 771-3549 LOGGED 81085801 LOG OF BORING NO. 8-4 Paae 2 of 2 -- CLIENT HOR Enalneering, Inc. SITE Highlands Site PROJECT City of Renton Renton, Washington Water Distribution System Storage Studv SAMPLES TESTS WELL (!) DESCRIPTION DETAIL ..J .~ 0 3 g a, ~ .... 0 ¢! ~ ¢! "'Ii !:: "' ~ :i: f 1/) UJ ':i z ~ l'.l a, w wl!! ::, :. a. 0 ti:3 1cz >-UJ 1/) ::, ~ UJ ;::8 C::'t; (!) 0 ::, z "' 1/) a, Oc. ·:)~·:\ -SP S-7 SPl 5014" 10 -SM =·· -.. ·.·_:_;. 35-... ·-=·:'· - I ···=·· --·· -\.:;~:::::: - ·.: 38.5 grades to gravelly 385.5 -SP S-8 SPl 50/6" --~· r-------~-t----~------·-- Boring completed at 38.5 feet on 10/14/08. No groundwater observed while drilling. No groundwater observed in piezometer on 10/23108. The stratification lines represent the approximate boundary tines between soil and rock types: in-situ, the lransilion may be gradual. WATER LEVEL OBSERVATIONS, ft ilzzA.:Jferracon BORING STARTED 10-14-08 WL V. J.!. BORING COMPLETED 10-14-08 WL 'l-J:¥. 21905 641h Avonue West, Ste. 100 RIG TRUCKJco. EDI WL Mounllake Terrace, WA 98043 RMS JJOB# V: (425) 771-3304 F: {425) 771-3549 LOGGED 81085801 LOG OF BORING NO. B-5 Pai:ie 1 of 2 I-------·-··-. CLIENT HOR Eni:1lneerlng, Inc. SITE Highlands Site PROJECT City of Renton o-~ _____ Renton, Washington Water Distribution System Storai:ie Study --~--~~--------+--~--~·~-·-SAMPLES . . . TESTS (!l 0 ..J (.) :i: i I '1:. ::v ••:I·•·, Well JD= BOREHOLE DIA.: WELL DIA.: DESCRIPTION GROUND SURFACE ELEV.: Grass over 2" Topsoil over SILTY SAND, trace gravel, gray-brown with slight iron oxide staining, medium dense, moist '· 5 SILTY SAND, with gravel, gray-brown, very dense, damp grades to gravelly grades to with silt, moist 61n 1 in 441ft 436 WELL DETAIL "' ( w " ---- g :. >-"' "' w "' Ol w (.) :; ~ "' :::, :::, z -SM S-1SP1 - 5----- -SM S-2SP1 17 16 88 6 !:: z :, >-C!:'tJ De. ------·-1----11---+--t--t----l - 10-- - -- -SM S-3SP1 -+-+---t-+--t--------~ - - 15---- - =,SM S-4SP1 50/3" - 20----- -SM S-5 SPl 5014" --l'--+--+-t---t--+--+-~1 -- 25--- -- -SP S-6SP1 50/3" = <>IVI - 30- ~ --. 30.5 " -SAND, wit_h_g-ra_v_e-l,-tr_a_c_e-to-w-it_h_s-ill-.---~4 ~ 10 =·.ci 5 /~::: j ~ 32 .5 gray-brown, very dense, moist 408 _5 :·: :E i· :· --- GS g1-...1-----·--c ... o_n_u_n_u, ... e .. d_N_e_xt __ P_a..._i:1,e ______ ..__ .... __ ..__.__.._.__. __ .__.__.._ __ --1 8 The stralifrcalion lines represent the approximate boundary lines ~ between soil and rock types: in-situ, the transition may be gradual. ~ WATER LEVEL OBSERVATIONS, ft l.t: rpzzA.:lrerracon1-B_O_RI_NG_S_T_AR_T_E_D ___ 1_0-_14_-0-18 BORING COMPLETED 10-14-08 0 WL :sf. ~ WL 1v. 21905 64th Avenue West, Ste. 100 Mountlake Terrace, WA 98043 V: (425) 771-3304 F: (425) 771-3549 RIG TRUCK I CO. EDI 1----------f-----·---- LOGGED RMS I JOB# 81085801 LOG OF BORING NO. 8-5 Paae 2 of2 CLIENT HOR Engineerina, Inc. SITE Highlands Site PROJECT City of Renton Renton, Washln11ton Water Distribution Svstem Storage Study SAMPLES TESTS WELL DESCRIPTION DETAIL .J .E 0 g '# ~ 0 :,: .J ~ "' "'Ii u "' "' i t: :i: :,: en UJ ';'~ z ~ t;: ~ "' w w~ CJ ::.: ~ u 6:S l;:Z >-w en CJ w ~8 [§ 'R. Cl 0 CJ z "' enm .. ·. = ·:_:_: -,SP S-7 $Pl 50/3" 8 :::·= : ... :.~ - ::/ -35-:::·~ .--,,·::::::: -·:·-= ::::_~ -·:,:.:-~ -SP S-8 SPl 50/5" ,' - 39.5 401.5 ·:.·-= '•'. -- Boring completed at 39.5 feet on 10/14108. No groundwater observed while drilling. No groundwater observed in piezometer on 10123108. The slratificatlon lines tep1esenl the approximate boundary lines between soil and rock lypes: in-situ, the transition may be gradual. WATER LEVEL OBSERVATIONS, ft lizzA.:Jrerracon BORING STARTED 10-14-08 WL 'Ii. I.!: BORING COMPLETED 10-14-08 WL )1. ____ L __ 21905641hAvenue West, Ste. 100 RIG TRUCK I co. EDI Mountlake Terrace, WA 98043 RMS IJOB# WL V: (425) 771-3304 F: (425) 771-3549 LOGGED 81085801 LOG OF BORING NO. B-6 Page 1 of 2 --· - CLIENT HOR Engineerina, Inc. SITE Highlands Site PROJECT City of Renton ~ _____ Renton, Washlnaton Water Distribution Svstem Storage Study SAMPLES TESTS Cl _J .~ 0 ~ ~ g DESCRIPTION "' ~ 0 ¢! :,; ¢! ,-: t: >-c,; ~ ffi~ J: ~ (/) w ';~ 2 (l_ (/) "' w ::, c:i 0 :,; n. 0 f-0 ~2 >- Approx. Surface Elev.: 437 ft w (/) ::, ~ w (l_ _J :;:8 ~g_ Cl 0 ::, 2 rr "'"' Grass over 2 inches Topsoil over SILTY - SAND, trace gravel, brown, very loose to --.... : loose, damp - -SM S-1 SPl 3 11 .. ·.· -: :,: 5 432 - SIL TY SAND, trace gravel, gray-brown, 5- dense, damp to moist - - - .-_ -SM S-2 SPl 44 ·. ----- - .-_,:._ 10-::_ -_._.· -- grades to very dense -SM S-3 SP 5014" 8 - - 15--= :-•' - - '• -•·-. ---=~M S-4 SP 50/.5" 6 ~ GS -- 20-- - -- .-·1.-.1-. grades to with gravel -SM S-5 ~Pi -50/6" 8 - - -:•_ 25 412 - SAND, with gravel, trace to wilh silt, 25 _ -.-__'.': gray-brown, very dense, moist -- <:: - -SP --- < S-6 SPi 50/5" - --- 30-> - - 232.5 - 404.5 -- Continued Next Paae The stratlficallon lines represent the approximate boundary lines between soil and rocl< types: in-situ, the lransillon may be gradual. WATER LEVEL OBSERVATIONS, ft fffllzzA.:Jrerracon BORING STARTED 10-14-08 WL 'SJ_ I-'-BORING COMPLETED 10-14-08 WL ,i 1-l'-21905 64th Avenue West, Ste. 100 RIG TRUCK\co. EDI WL Mountlake Te1race, WA 98043 RMS IJOB# V: (425) 771-3304 F: (425) 771-3549 LOGGED 81085801 LOG OF BORING NO. B-6 Page 2 of 2 ,--- CLIENT HDR Enalneerlna, Inc. SITE Highlands Site PROJECT City of Renton Renton, Washington Water Distribution Svstem Storage Study ---- SAMPLES TESTS 0 ..J .E 0 "$. ~ 0 DESCRIPTION Cl) iii ..J :;; " ,-: t::; 0 " >-0: § ~ o:z :i: :i" "' w ';'1@ z ~ ti: "' Cl) w ~~ :, 0 :;; 0. ~~ >-w "' :, ~ w is ,q, 0 0 :, z oc 0 C. ·/ SP S-7 SP 50/6" 6 ---·--: - 35--!i< --- 1:e 39 -SP S-8 SPl 50/5" 398 - Boring completed at 39 feet on 10/14/08. No groundwater observed while drilling. The stratification lines represent the approximate boundary lines between soil and tock types: In-situ, the lransilion may be gradual. WATER LEVEL OBSERVATIONS, ft llzzA.:Jrerracon BORING STARTED 10-14-08 WL 51. l'f BORING COMPLETED 10-14-08 --- WL '51. 1.1c 21905 64th Avenue West, Ste. 100 RIG TRUCK I co. EDI Mountlake Terrace, WA 98043 RMS I JOB# 81085801 WL V: (425) 771-3304 F: (425) 771-3549 LOGGED LOG OF BORING NO. B-7 Paae 1 of 2 - CLIENT HDR Enaineerina, Inc. -----------------· SITE Mt. Olivet Site PROJECT City of Renton Renton, Washington Water Distribution S}"stem Storage Study ----~ SAMPLES TESTS Cl ...J .s 0 ;ft ~ g DESCRIPTION m ,.: 0 "' ! QC "' .--!:: QC w z JC :i w 6 ';~ QCW z [l. Ii: "' m w ~~ :, ii'! 0 ::; [l. 0 1,:g >- Approx. Surface Elev.: 164 ft w "' :, 1=: w ~8 ~'R Cl 0 :, z QC "'"' --·-- \} 2" Ashpalt over SAND, trace silt and - gravel, brown, medium dense, moist - ·. __ .· ---. :• -SP S-1 SPT 12 9 .. _:/ - -.. c: 5--t: - -- .· ..... ·.··. grades to with silt to silty, dense -SP S-2 SPT 32 ·ii -SM -- -.. 10-= ·. :• 11 15~ - 1.·· SILTY GRAVELLY SAND, gray and - brown, dense, moist . I/ -SM S-3 SPl 38 -5 - : . -[.,.:. 15-- •: -.·. - !) - grades to very dense -S-4 SPl ---50/2" No _ __J - r -Recovery ·- 20---- ---- grades to wet -SM S-5 SPl 50/3" 11 25--= --- -:-: -SM S·6 SP 50/6" 'fl. -- "-' - : · 30 134 - SAND, with silt to silty, brown, dense, wet 30--=: to saturated --:.:·-.· 32.5 131.5 --- Continued Next Pa<1e The stratification lines represent the approximate boundary lines between soil and rock types: in-situ, the transition may bo gradual. WATER LEVEL OBSERVATIONS, ft BzzA.:f f erracon BORING STARTED 10-15-08 WL 'fl_ 29.0 wolY BORING COMPLETED 10-15-08 wi. si ~ 21905 641h Avenue West, Ste. 100 RIG TRUCK I CO. EDI WL Mounllake Terrace, WA 98043 RMS I JOB# --·-- V: (425) 771-3304 F: (425) 771-3549 LOGGED 81085801 LOG OF BORING NO. B-7 Paae 2 of 2 CLIENT ,_ ______ H_DR Ef!alneerlna, Inc. SITE C) 0 _, 0 'i: Q_ ~ C) <lit 34 Mt. Olivet Site Renton, Washlnaton DESCRIPTION ------- Boring completed at 34 feet on 10/15/08. Groundwater observed at 29 feet while drilling. 130 PROJECT City of Renton Water Distribution System Storaae Studv SAMPLES TESTS ..J .s 0 .... ~ ., ,: ~ ¢i ¢i " i-: I-" ~ "z z :c "' w ';~ t "' ID w ~~ ::> 0 ::;; "-0 1-0 >-w "' ::> ~ w Q_ _, !8 l's 8. Q ::> z " (I) ID -SP S-7 SP1 31 24 -"'" ~I-..J.-------------------i....-.i.. ................ _ ... _ ... _...1,,_..., __ ._ __ ..... ~ ~~~~~~t:1:~~~ 1:~~: r;&!!~~~~~~~. ~~~r~:i::}~t~~~d~i ~~::~al. w1-__;.;.;..._;_..;,___;.;_;;,;_ __ ...;. ___ ...,...;......;;... _________ .,.. _____________ -I ~ WATER LEVEL OBSERVATIONS, fl PzzA.:Jrerracon,._B_O_R_IN_G_S_T_A_RT_E_D ____ 10_-_15_-0_8_. £ WL 'Sl 29.0 WD I?: BORING COMPLETED 10-15-08 g WL SI. ll'. 21905 64th Avenue West, Ste. 100 ~--TR--UC_K_l_c_o _______ E_D_,I ~ WL v, (~titm~31g:·~\~:i m~:549 LOGGED RMS I JOB# 81085801 _______ ..;.P~a~g~e -'-1 """o-'-f 2___, LOG OF BORING NO. 8-8 -·------~---- ·. CLIENT SITE HDR Englneerlna, Inc. Mt. Olivet Site Renton, Washington DESCRIPTION ~ Well ID= APQ-799 ~ ~i~~~?t~ DIA.: C) GROUND SURFACE ELEV.: :·. Grass over 2 inches Topsoil over SIL TY SAND, trace gravel, brown, loose to medium dense, damp 6 In 1 In 166 fl ~ ~ L ------------------'1"'"-51 SAND, with gravel, trace silt, brown, << medium dense, damp to moist i\·c::: ? >> l'<+;.+c12..,.a,,_~====--cc----c-c-----c.----1fil SIL TY SAND, with gravel, brown, medium :: 16 dense, damp SILTY SAND, with gravel, gray-brown, very dense, moist grades to dense grades to very dense, wet to saturated 140 PROJECT City of Renton WELL DETAIL Water Distribution System Storaae Studv SAMPLES TESTS ---- _, 0 a, ~ ffi (I) a, ~ ~ ::, z -SM S-1 SPl - 5----- -SP S-2SP1 - 10 6 !:: z ::, >- 0'. 'tl 0 Q. --+-__!f---f----j 18 4 ----+----+-+--f----1---1---l 10· ---- -SM S-3SP1 25 9 - -15----- -=SM S-4~Pl 53 - 20----- -:. SM S-5 SP1 45 10 - - 25-- -- -SM S-6SP1 55 GS $' WATER LEVEL OBSERVATIONS, ft iif zzA.:n:err~con BORING STARTED 10-15-08 ~ WL 'fl. 33.0 WD j:f. 28.0 10-23-08 ·Ill II.I I-B-O_R_I_NG_C_O_M_P_L_E_TE_D ____ 10---15---08-I 0 WL :!. l'f 21905 64th Avenue West, Ste. 100 RIG TRUCK) CO. EDI ~ WL~-v, (~;im~~r~~·?i:z:i ~;~~:549 LOGGED RMS I JOB# a1085801 LOG OF BORING NO. B-8 Paae 2 of2 ---CLIENT HOR Engineering, Inc. SITE Mt. Olivet Site PROJECT City of Renton Renton, Washington -~-.---Water Distribution System Storage Studv SAMPLES TESTS WELL G DESCRIPTION DETAIL ...J .~ 0 'if'. 3 g co t 0 "' ~ "' ..: t: a: ~ di :i: :i w ".'~ z Q. Ii: V) co w 0 ~!z :, ~ 0 ::. 0. 0 l,:g ,.. w V) ::, ~ w ;;:8 O'."tJ (!) 0 ::, z a: (/) co 0 Q. >JH 34 SAND, with silt to sllty, gray, very dense, ·"-~· -SP S-7 SPl 56 22 saturated 122 -SM Boring completed at 34 feet on 10/15/08. Groundwater observed at 33 feet while drilling. Groundwater observed at 28 feel on 10/23/08. The stratification lines represent the approximate boundary lines between soil and rock types: in-silu, the transllion may be gradual. WATER LEVEL OBSERVATIONS, ft lllzzA-=lrerracan BORING STARTED 10-15-08 "l. 33.0 wol~ 28.o -- WL 10-23-08 BORING COMPLETED 10-15-08 WL i··--jl'. 21905 64th Avenue West, Ste. 100 RIG TRUCK Teo. -~EDI Mountlake Terrace, WA 98043 WL V: (425) 771-3304 F: (425) 771-3549 LOGGED RMS IJOB # 81085801 LOG OF BORING NO. B-9 Page 1 of 2 ---- CLIENT HDR Engineering, Inc. ----- SITE Mt. Olivet Site PROJECT City of Renton Renton, Washlnaton Water Distribution Svstem Storage Study SAMPLES TESTS (') _, .£ 0 ~ g DESCRIPTION m -,; ',f!. "' :;; a: "' ~ t: 0 >-a: ~ -I' t Cl) U! ';'~ a: U! z a. Cl) "' U! 0 Ult-:, ~ a. 0 :;; a. 0 1-0 ~z >- Approx. Surface Elev.: 153 ft U! Cl) ::, r: U! a._, :s:8 g; g_ (') 0 :, z a: Cl)al )· Grass over 1 inch Topsoil over SAND, - trace gravel and silt, brown-gray, medium - n - dense, moist - -SP S-1 SPT 16 4 1--< - - r--:.:::- 5--:: - ( - ·---SP S-2 $Pl 19 6 GS 1:;: - ·-"::--I> 10-- ti: - -- -SP S-3 SP -- 23 9 grades to with silt !/< -SM -15-:-.::-. --_· . .- ·-.-·--> - < grades to trace silt -SP S-4 $Pl 26 - tt - 20- ---\ -- -SP S-5 SPl 26 12 ( - ,--- - 25- > --- > - SPl -~ ~ grades to with gravel -SP S-6 20 - . .-_ ._-:---- .:., •:-: 31 122 30-=- -J1 SILTY SAND, trace gravel, brown, - 32.5 medium dense, wet 120.5 --- Continued Next Paae The stralification lines represenl the approximate boundary lines belween soil and rock types: in~situ, the transillon may be gradual. WATER LEVEL OBSERVATIONS, ft P1zzA.:Jrerracon BORING STARTED 10-15-08 I-'- --~-------- WL 'l-BORING COMPLETED 10-15-08 WL ~ \-l:' 21905 64th Avenue West. Ste. 100 RIG TRUCK\co. EDI -----· Mountlake Terrace, WA 96043 ----· RMS I JOB# WL V: (425) 771-3304 F: (425) 771-3549 LOGGED 81085801 LOG OF BORING NO. 8-9 Paae 2 of 2 ·---"" ----· CLIENT HDR Engineering, Inc. SITE Mt. Olivet Site PROJECT City of Renton Renton, Washington Water Distribution System Storage Study SAMPLES TESTS <.? ...J .£ 0 ~ ~ 0 DESCRIPTION Ol ~ ...J ~ ~ i-: t: 0 ¢i Cl'. 'i: ~ LIJ ~ ';~ Cl'.z z ~ ~ Ol w ~~ :::, ;;; a. 0 t;:g >-w (/) :::, ~ LIJ f8 g\'R_ <.? 0 :, z Cl'. (/)0) tr -SM S-7 SPl 23 1i 34 119 Boring completed at 34 feet on 10115108. No groundwater observed while drilling. The stratification lines represent the approximate boundary lines between soil and rock types: in·situ, the transiUon may be gradual. WATER LEVEL OBSERVATIONS, fl 11:~ZZA.:Jferracon BORING STARTED 10-15-08 WL :I.. j! BORING COMPLETED 10-15-08 WL 'l'. 21905 64th Avenue Wesl, Ste. 100 RIG TRUCKjCO. EDI Mountla~e Terrace, WA 98043 - WL V: (425) 771-3304 F: (425) 771-3549 LOGGED RMS I JOB# 81085601 APPENDIXB LABO RA TORY TESTING PROCEDURES AND RESULTS APPENDIXB LABORATORY TESTING PROCEDURES AND RESULTS A series of laboratory tests were performed during the course of this study to evaluate the index and geotechnical engineering properties of the subsurface soils. Descriptions of the types of tests performed are given below. Visual Classification Samples recovered from the exploration locations were visually classified in the field during the exploration program. Representative portions of the samples were carefully packaged in moisture tight containers and transported to our laboratory where the field classifications were verified or modified as required. Visual classification was generally done in accordance with the Unified Soil Classification System. Visual soil classification includes evaluation of color, relative moisture content, soil type based upon grain size, and accessory soil types included in the sample. Soil classifications are presented on the exploration logs in Appendix A. Moisture Content Determinations Moisture content determinations were performed on representative samples obtained from the exploration in order to aid in identification and correlation of soil types. The determinations were made in general accordance with the test procedures described in ASTM: D-2216. TI1e results are shown on the exploration logs in Appendix A Grain Size Analyses A grain size analysis indicates the range in diameter of soil particles included in a particular sample. Grain size analyses were performed on representative samples in general accordance with ASTM: D-2487. The results of the grain size determinations for the samples were used in classification of the soils, and are presented in this appendix. GRAIN SIZE ANALYSIS TestResultsSummary SIZE OF OPENING IN INCHES 10 0 - 0 - 0 9 1-::c 8 <.? w 3: 7 - 0 -in ffi 6 0 z ii: - !z 5 0 w (.) - ffi 40 0. - 30 - 20 - 10 - ,.. 0 1000.000 12" r ,. 1i~ 100.000 U.S. STANDARD SIEVE SIZE ,,,. 318" • 10 20 40 60 140 200 I \ ''- " "" ' \ \ ~ \ - 10.000 1.000 0.100 PARTICLE SIZE IN MILLIMETERS Fina· Coarse Medium Fine BOULDERS COBBLES GAAVEL SAND Exploration Sample Depth (feet) Moisture(%) B-2 S-3 12.5-13 6 JOB NO: 81085801 ~ ZZA·lrerracon DATE OF TESTING: 10/27/2008 Geotechnlcaf and Environmental ConsulUng ASTM D422 HYDROMETER ---· .. 0.010 0.001 Slit Clay FINE GRAINED Fines(%) 30.7 Description silty SAND with gravel PROJECT NAME: Water Distribution Storage Study GRAIN SIZE ANALYSIS TestResultssummary SIZE OF OPENING IN INCHES 36" 10 0 - 9 0 0 - 0 - 0 - - 30 - 20 - -1 ·1 10 0 1000.000 12" .. 3" 1112" I I I I I ·- 100.000 U.S. STANOARO'SIEVE SIZE ,,,. i • 10 20 40 60 , .. 200 I I --.._11111 I I _I "" " --- "" !\ ' I\ \ \ -- \ I 10.000 1.000 0.100 PARTICLE SIZE IN MILLIMETERS c.,.... Fine CoaNie Medium Fine BOULDERS COBBLES GRAVEL SAND Exploration Sample Depth (feet) Moisture (%) B-4 S-3 12.5-13 7 JOB NO: 81085801 ~ ZZA-lrerracon DATE OF TESTING: 10127/2008 Geoteehnlcal and Environmental Consulting ASTM D422 HYDROMETER -c--- 0.010 0.001 sn, Cloy FINE GRAINED Fines(%) 32.7 Description silty SAND, trace gravel PROJECT NAME: Water Distribution Storage Study GRAIN SIZE ANALYSIS Test Results Summary SIZE OF OPENING IN INCHES 10 9 !i: 8 (.!) jjj 0 - 0 - 0 - :1: 7 0 ~ - ffi 60 z ii: - 36" !z 50 w (.) ffi 40 0.. -I - 30 - 20 - 10 - 0 1000.000 12" .. 3• 1112" I 100.000 U.S. STANDARD SIEVE SIZE 3/4" 318" ' 10 20 .. i ... 200 ~ .. :,.., ' "' I) \ ' I\ \ I 10.000 1.000 0.100 PARTICLE SIZE IN MILLIMETERS Coarse Fine Coan>& Medium Fine BOULDERS COBBLES GRAVEL SAND Exploration Sample Depth (feet) Moisture (%) 8-5 S-2 7.5-9 6 ~ ZZA·lrerracon JOB NO: 81085801 DATE OF 10/27/2008 Geotechnical and Envlronmenlal Consulting TESTING: ASTM D422 HYDROMETER I 1 0.010 0.001 Slit Clay FINE GRAINED Fines(%) 31.8 Description silty SAND with gravel PROJECT NAME: Water Distribution Storage Study 10 0 0 9 1-:c 8 Cl 0 - - i 70 ~ ffi 60 z u::: - !z 50 w -(.) ffi 40 Q. - 30 - 20 '- 10 - GRAIN SIZE ANALYSIS Test Results Summary ASTM D422 SIZE OF OPENING IN INCHES U.S. STANDARD SIEVE SIZE HYDROMETER 36" 1Z' .. 3' 1112· 3/4' 318' ' 10 20 " "' 140 200 I I \ -\ \ \ ~ ~ \ ~ " ~ i ' \ ' ~ 0 1000.000 100.000 10.000 1.000 0.100 0.010 0.001 PARTICLE SIZE IN MILLIMETERS Coarse F1ne Coarsa Medium Fine Slit Glay BOULDERS COBBLES GRAVEL SANO FINE GRAINED Comments: Sample did not meet minimum mass requirements based on maximum particle size, per ASTM D 422. Exploration Sample Depth (feet) Moisture (%) Fines (%) Description B-6 S-4 17.5-18 6 11.4 sandy GRAVEL wilh silt JOB NO: 81085801 PROJECT NAME: ~ ZZA·lrerracon DATE OF 10/27/2008 Water Distribution Storage Geotechnical end Envlronmentaf Consulting TESTING: Study GRAIN SIZE ANALYSIS Test Results Summary SIZE OF OPENING IN INCHES 10 0 0 9 !i: 8 (!) 0 - - - ~ 70 ~ ffi 60 z ii: - !z 50 w -u ffi 40 a.. - 30 - 20 - 10 - ,... I 0 1000.000 12" ,. 3• 1112" I I -- --···- 100.000 U.S. STANDARD SIEVE SIZE 3/4" lW" 4 '1 20 40 i 140 200 I I -i ~, J -·~- \ \ -- \ ~ \ \ I ~ 10.000 1.000 0.100 PARTICLE SIZE IN MILLIMETERS Coarse Fine Coarse Medium Fine BOULDERS COBBLES GRAVEL SAND Exploration Sample Depth (feet) Moisture (%) B-8 S-2 7.5-9 4 JOB NO: 81085801 ~ ZZA·lrerracon DATE OF 10/27/2008 Geotechnical and Environmental Consulting TESTING: ASTM 0422 HYDROMETER ·- 0.010 0.001 Slit Clay FINE GRAINED Fines(%) 4.6 Description SAND, trace gravel and silt PROJECT NAME: Water Distribution Storage Study GRAIN SIZE ANALYSIS Test Results summary ASTM 0422 SIZE OF OPENING IN INCHES 100 90 1- - ,.. I ! i 12· I I I ti·· I'; I, '. ! :c 80 Cl i ! ii w - I ~ 70 > -I aJ ffi 60 z ii: - I I ! i !z 50 w 0 ffi 40 0. -11 ( - 111 - 30 20 - 10 -f I 0 1000.000 ! I' ii I I t I I .. 3• 1112· I I i I I I i- I I i 100.000 3/4~ 318· 4 ."" 11. 1,, -- ' f------ i 10.000 U.S. STANDARD SIEVE SIZE HYDROMETER 10 20 " .. 140 200 I I I I 11111 ii! i I fl I Iii I ---. . ' !l; ---I ij I ! I "i\. I I \ --~- --··· i ------· I I I I I I \I --+---··- I I i I • ' --·-f-- \ \J i ! I -· -· ---,---- I I I I ! I I 1.000 0.100 0.010 0.001 PARTICLE SIZE IN MILLIMETERS Coat.Sa Fine Coarse Medium Fine Silt Clay BOULDERS COBBLES GRAVEL SAND FINF. GRAINED 1--E_·x_D_lo_ra_1i_o_n_+-__ s_a_m~p_le __ 1-_o_e~pt_h_(_fe_et_)_,__M_o_is_t_ur_e_(0_Vo_) -+--F_i_ne_s_(_%_)--+ __ D_es_c_ri_pt_io_n_-< B-9 S-2 7.5-9 6 6.4 SAND with silt and gravel JOB NO: 81085801 PROJECT NAME: ~ ZZA·lrerracon DATE OF 10/2712008 Water Distribution Storage Geotechnlcal and Environmental Consulting TESTING: Study APPENDIXC THRESHOLD DISCHARGE AREAS SSMHV~JB ..==~~- ·.~··fl'!!. MONROE Ant NE G--55------~·, -;::..y;,e-_-.;::•~-~C-!5i~p!_~----f"Q. ----••/JI ill' --·--•• C.• (J~(OTY<l' ...... C<JNIRO. 0 -•rl4JI .(' NM. It CCltC '(.r "'.1'..r ~JttCA!E u:··-_ -~, .... J) n~~~J~ lj ·.:::~ 1'·-... 1', .. 1, j ', I !Ul/t'UM """' ...,,_ (12/17/20U) __ L,,", __ ----- !UN~~~ J I (IW) I I STORM STRUCTURE TABLE ~ r::f,,'N ~::,. ::=1:::2 ===~ :::1=~., ::,;,ql.M.-..0 'fl=--·IJ.11 ::=., r-=---,-.11 ;r.,. ::~i:::i:r =~Miro~,~=~:: J:...,.~ .. _.. ,:WIOIII&:;:_ -r=a r-.. ----,~~,,--g"-· 111!\lllf-f(I 'i":,,,, ::::=~ .'11!::"J :;:17!"1.. ==--r t-:.~·-" r'~.l(QJ.# ...... ,..._ .... ~ ~ rc...e•.,,.#ton-D ~Tl&1i. ----w i.E~!i,- EXISTING SITE PLAN ,,..._ ,-. == SEWER STRUCTURE TABLE WATER STRUCTURE TABLE I j 11 I :-t= s:::u=:w ~--=====Er --r='~ f.':~- 'I tf81111a(,'l'IP. 'l:W ::s~H ... .. _ • ..,..41t-411 ,,_ .... ,..., ~ ::::~~=r::e., I 623.50' =~·--"'" --......... .~,,,,an:_• :,,r -~:S.--., :n:=f&W :n::: .... ••.C1/IN19 ......... ., .. ,,ww:-...w ~ --7 I --· ---· --/ 'vfi!!iC-' I I I !iU 1/r' 1UM ..., "' ~,,,,. -' / # i / I , # I / / I _,,-or• ----•"QI w _-.f ) r ET vr 1DN1 "'"" ...,,_ c12m/201>1 ~ sc,r,.19 e e q l ~I, ~h I ~ ~ a. w !: I .fi 11 I ii mH •'4 I I II SI 111 11 11 Ii IC.Ille-~ -·-.. ---· AOORE 1 I'":: ..... APPENDIXD SALMON HABITAT WRIA8 .:)1~ht'"~ _h x Find: dd1n Horne • Topo Map "_/ [-]+ ,J ,.:~~ •"";.+· ,I ,.,r T A .~ :../' '\, •-1uc1to1 -17.5-12~01 ~-~ " • Map Features ft·/, • • LV:e S.1mma,m'>h '3"-t,ite r-\1rt Q '..:.Lfi:.[J(NT·-,o-~r Iii h-ws.~kosyst~m.us I ·'r __/. ·43 ,d,w · ,,. \ ~ \ ,,. \ \. <,: " . \ ., \. •• • ;f-l ~'I 1 -' ti_l- / ////,i // I"' \ ~i • I > ... <( z .c.:.. -C u 'O, i \\ le<?Li"ill!Q!l!IJ ,-: r, ~ti: APPEND/XE DOWNSTREAM ANALYSIS .. ,,.,.,;,..:· ~~::~x;~- ·,.,,.,- ~({;-·-.{~, ! ,·,,f -"~~ ·-. ~I 8 10 -FIL ! u.i > ~- ,--....... ,. I !-!.-> . -...,,,.,, -' .· "-, . .;. . ~ -(.. -._':,wf..-.• '~e,< ~ ~ ';'.; :~1 '> LEGEND Hist or ic Basi n F lows Basin Flows Retirement Residence Constructed ---.~ __.,,,,. ---· -_.....------;:.:.,"---~-. _____.. 0" Jl:.,';'/i,"''"-, , N ~€, I [•·•'•• -• e~~O ---;;..;; ,n c V(.E>,1.1uro,1.osP1,rEo.r·roorsoir.,. f ~f iF:~:t~~1l0:1:.scr 8 1 Y~ ~1Surface water from Highlands Reservoir Site collected and routed to Honey Creek Re nton Highland s Re se rvo ir Site ROLL 179 FR 319 ~~ ~ --~r---- to ll .)IIIOTc _ 1 ,.~,_ 11,.'-.. u S11,L t u eo1 .u 1m» IL'"'."'! z.,G, ~~'":tlr~lt#,r;:rr I Pl'/0/' RECOMMEN O'E O R)fl~OV4.L , ,. ~-ii f ,i ! If j I· I . ! .. !I !Fl ii I .... cs ~ ~ ~~; -~i... .... ~<!: l_,u lu ;,'! n,; <::i ---q ~t3~ ~Q:~ C1 ~ Q:: q,o t "--.. 2 «6 _ P '-1 F S 2-f I J 4 L, I . I f 680 0 WGS _ 1984 _ Web _Mercator_ Aux il iary_ Sp here City of Renton Stormwater Collection System 340 680 Feet R enton M apSupp ort@ R entonwa.gov 11 /21 /2014 Pro posed Storm Pr ess ure Force Main Propose d Grav ity Fl ow Route This map is a user generated static output from an Internet mapping site and is for reference only. Data lay ers that appear on this map may or may not be accurate. current. or otherw ise reliable. TH IS MAP IS NOT TO BE USED FOR NAV IGAT ION Legend City and County Boundary Other r:J City of Renton Parcels Network Structures la Inlet O Manhole U1i1rtyVautl. a Un~mown Structure Pump Station Di scharge Point Pipe Culvert Open Dra ins • Facility Outline Private Network Structures Inlet O Manhole [] Ut1lityVa utt Unknown St1ucture • Private Discharge Point Pr ivate Pipe Private Culvert Private Open Dra ins Private Facility Outlin e Flow Control BMP Stormwater Ponds Facility Transfer Downstream Analysis for North R enton TOA 0 ~t1fon1~J Finance & IT Division 680 0 WGS _ 1984 _Web_ Mercator_ Auxi liary_ Sphere City of Renton Stormwater Collection System Legend City and County Boundary 340 680 Feet RentonMapSupport @Ren tonwa .gov 11 /21/2014 SID Flow Direction Picture # and Direction ( see next pages) Other :-·, C 1tyot Renton L,,; Parcels Network Structures 1:1 lnle1 0 Manhole a Utility Vault • Unknown Structure I!!] Pump Station 4 Discharge Point -Pipe -Culvert = Open Drains • Facility Outl ine Private Network Structu res ' Inlet 0 Manhole D Ut1 lityVauH " Un known Structure • Pr ivate Discharge Poi nt Private Pipe -Pr ivate Culvert -Private Open Drains • Private Facility Outline 8 Flow Cont ro l BMP D Stormwater Ponds • Facility Transfer Notes Downstream Analysis for Honey Creek TD A 0 This map is a user generated static output from an Internet mapping site and is for reference only. Data layers that appear on th is map may or .may n.ot be 1 1 City of n .-a.....--Fon c,· accurate , current , or otherwise reliable. ~..ft\..,,•• L THIS MAP IS NOT TO BE USED FOR NAVIGATION Fin ance & IT Division 680 0 WGS _ 1984 _Web_ Mercator _Auxi li ary_ Sp here City of Renton Stormwater Collection System 340 680 Feet Rento nMap Suppo rt@ Re nto nwa.g ov 11 /21 /2014 This map is a user generated static output from an Internet mapping site and is for reference only. Data layers that appear on this map may or may not be accurate, current, or otherwise reliable. THI S MA P IS NOT TO BE USED FOR NAV IGATION Legend City and County Boundary Other :--·, C1tyol Renton l.,; Parcels Network Structures Iii Inlet 0 Manhole a Ut1l rtyVault • Unknown Structure II[] P um p Station t Discharge Point -Pipe -Culvert = Open Drains • Facil ity Outline Private Network Structures -Inlet 0 Manhole CJ Utility Vault " Un known Structure • Pr ivate Discharge Poin t Private Pipe -Pr ivate Culvert -Private O pen Drains • Private Facility Outline 8 Flow Control BM P D Stormwater Ponds • Facil ity Transfer Notes Downstream A nalysis fo r Honey C reek TO A 0 City of Rerrfon ,:-,; Fina nce & IT Divisio n PICTURE 3 -Further Downstream of 18-inch Culvert Outfall (heavily vegetated) APPENDIXF RESOURCE REVIEW II II . No,tt,H,g,111,V,tll .... g,11~0,0,000 1 ~' ''" c~,~ " II II II II II Ir II II II I "' Notes None I 459 ; ! l'l ... '10" ~ Sl,Y!•9ni2 ,.,.1 ,1N·"' (~ J 0 230 WGS_ 1984_ Web _ Mercator _Auxiliary_ Sphere 459 Feet ~1rron€} Finance & IT Division j! I Legend ' ~ N t • 11h ~' ! r City and County Boundary 01he, [:] CJty of Rentoo Parcels Slope City of Renton >15%&<=25% • >25% & <=40% (Sensitive) • >40% & <=90% (Protected) • >00% (Protected) l=nvirrmmPnf nF>-.:inn:'ltinnc:;: Information Technology · GIS RentonMapSupport@Rentonwa .gov 6/13/2014 ,ioi, PROJECT LOCATION O Shoreline Residential D Urtlan Conser,,,ancy 0 Jurisdictio ns 1 '=I ===:;:::======C=i=ty=o=f =R=e=n=t=o=n=·=L=a=n=d::;:::s=l=id=e==========::::::::: - II II . N Oflh 1"•!11'>\,lor\ .. N••Q,IIH•fl- 1 ~/ ·~,~ s, <: ... t ... II II II II II R•>1 oo1 Stm,o"'' Ir II II ' ,{ , o" •" II ,' ·V :' Notes None II II 11459 .. ,.,, ...... .. l.,,, ....... . ..,, •' ,,""' •' 0 0 230 WGS _ 1984 _ Web_ Mercator _Auxiliary_Sphere ,. 459 Feet City of R-etffijjft: Fi nance & IT Division ' j .. l ! 111, ~ • N{l/1 •1S, .. r '""~' Legend City and County Boundary [' ~ City of Renton Parcels Landslide • VERY HIGH • HIGH • MODERATE UNCLASSIFED F nvirnnmAnt n ~c:.inn::1tinnc:. Information Tec hnology · GIS RentonMapSuppon@Rentonwa .gov 6/13/2014 ;, I ~i '·-·-·----~ '""'' ,oc.i ~ ... ., c, ... i PROJECT LOCATION D Sh0reline Resldent,al D Urban Conservancy 0 Jurisdictions Jh,, r1a~ ,s a user gerera:ed s:at,: 0~·1:u 1 fr om an l1 ter1 et n·app ng s1ttc ilnr. ,~ •::,, re'erence 011y Uc!'.<' layer$ t~a1 ;'lppe;;, 01 :r,s map nay or nay no: be c1:rur.i·c current. or other.\,~€ rel able THIS MAP 1$ NOT TO BE USED FOR NAVIGATION 1 ;:::I =;::::::======C=i=ty=o=f =R=e:::::;n;::=t=o=n=-=S=tr=e:;::::a=m=s==;::====;::====~ .. ;, . ... o<thH, ... l,>tlcls ..... r~:00<1 Notes None h' , ~rr, !S I ,.,.1 ,~··· ~\ ('!V 0 230 WGS _ 1984 _ Web_ Me rcator_ Auxiliary_ Sphere 459 Feet City 0 ~-eliton C Finance & IT D ivision I ~i ~i·-·-·----~ '""' I ' '""l'll .... , ! Legend City and County Boundary Other [:] Oty of Renton Parcel s Streams (Classified) Information Technology · GIS RentonMap Support@Rentonwa.gov 6/13/2014 ,, •,,,~ "', -~~ .. , ......... ~.~ - f " 1 PROJECT LOCATION ! \ HI ,111,SI 11 II II . ........... .,,.1.. ..... d "--r~:- l k ,6,,,~! II II II II i II "'"'"0" ! £,t;tl,0<112 Ir (~ II II ft/ .. i •' II /· I "' :' Notes None II II 0 11459 0 230 WGS_ 1984_Web_Mercator_Auxiliary_Sphere City of Renton -Wetlands (1Nci; ~-}' .,i"l ,' , , ' <e Nt•rn,r, ! ' '\.,...,,. Legend City and County Boundary ' Othe, r:; CityofRen1on Parcels D Wetl and s 459 Feet ;1 I ~i i ......... .!I; '"" .. PROJECT LOCATION i l ' C it y of R-e tifon(: Information Technology • GIS RentonMapSupport@Rentonwa .gov Fi n ance & IT Division 6/13/2014 c-' 1 '=1 =======C=ity=o=f=R=e=n=t=o=n=-=E=r=o=s::;:io=n=========: II II .. t ,,,,,. ~· II •, II 11 II II I~:::::· II f ,' /l II II II (Ol:>fj . .... , .. ,;,g,r,bn• N .. \llllo<>rt\- C .. u ... 's1,,:,;, ,;i.,.,,o,, SUt·o.,12 .l Notes II II 0 11459 230 WGS _ 1984_ Web_ Mercator_Auxiliary_Sphe re 459 Fee1 Ci t y o~-errfojfQ Finance & IT Divis ion i <I N l 1 •1t, ~t I Legend City and County Boundary Other r:1 City of Renton Parcels Eros ion RentonMapSupport@Rentonwa .gov ;, -"i i.,_,,_•-•-•~ llilh~I •, , .. ,.., .. , C . 5 .. ,..,,, ... N/!,""••tH,,.,,~ PROJECT LOCATION City of Renton -Flood II'=================::;:==========: II II II II II II . to O<ll'I H ,fl'l~"-N.,r!~:- ,.,,,,,,.c,, (""'!'J ' ,i ' "'~l 1 /U, r , j ;, I ~i i--·-·----~ """ \,.,~,, ,, ,,.,, ~ ...... ; ..... II "'",;f I~::::" II ;, ,· ," /'°' ; II II II Notes ~ .. ,t(m su1o o,,,2 Nothing Mapped for Flood Pla in, Flood Way, etc. II II ~ f , 11459 230 459 Feet WGS_ 1984 _ Web_Mercator _Auxiliary_ Sphere City of R-enlon e Fi nance & IT Division Legend City and County Bou ndary 01 her r:J Oty of Re nton Parcels till Floodway Special Flood Hazard A reas ( 100 year flood ) Other Flood Areas (Zone X -500 year flood) Information Technology -GIS Rento nMapSupPort@Rentonwa.gov 6/13/2014 PROJECT LOCATION THIS MAP IS NOT TO BE USED FOR NAVIGATION City of Renton -Coal Mine I '=I ===================;:;:==::::;==:::;======; :, " I ~i II II .. \•{•'''"'' . N"'l~ H,IJf>l,),\,h N .. r!~::"OOd II ... f ,,,~ s, II II II II If'.:::·:- II :, ,' / ,• i' II II II Notes Nothing mapped for coa l mine hazards 0 1 459 230 459 Feel WGS_ 1984_Web_Mercator_Auxiliary_Sphere City of R-errfoilC Finance & IT Divis ion ' .. 'll , •u, ~ ! Legend City and County Boundary Other [:J Ci1y of Renton Parcels Coalmine • HIGH • MODERATE UNCLASS IFI ED Information Technology · GIS RentonMapSupport@Rentonwa .gov 6/13/2014 i•-•-•-•-•~ •!i!l'>Sl •, •, '~,, """" ~ .... 'II s.,,,0.,,n,~,, - PROJECT LOCATION ; ' II II II II II II / ,/l II (Ni) Notes • 1 i ,t.,l .... !: .O,<Of111 NE 1?1~ SI h '" ... 0 0 230 WGS_ 1984_Web_Mercator_Auxiliary_Sphere City of Renton -Aquifer ! 459 Feet Legend lllt '"""' -.. '· .. City and County Boundary r:; Oty of Renton Parcels Aquifer Protection Zones Zone 1 • Zone 1 Modified zone2 Wellfield Capture Zone • One Year Capture Zone •,, '1 .. , Cityof-R-etiton c Information Technology. GIS Ren1onMa pS upport@Rentonwa.gov Finance & IT Division 6113/2014 ... -· ... •, PROJECT LOCATION JS .,..,, •Ill I 3N•"'11•0.Ju~ 11 ~1.....t.,,I t I ,~_.,,,,c; ~- >ols C ·'''j -I'...; .. (-rj ;JV - "-.,. .. "'"•<l" """" •[ (:::) Active; ",.,,,.,. "'j.. .. ,,) r-1· 1\ J. ~ zR•no Id~,-;: "•e: w z . ~ . As sessment Hydro Boundaries latitude; 47 .51392 longitude: -122 .2 1472 2 listings fou nd Datum: N AD 8 3 HARN !Listing mH Name II Parameter UMedium!!categoryj l waterbody ml !12195 l!WASHINGTON LAKEUBacteria Uwater 1~112224414 761971 ~!WASH INGTON lAKEIJTota l Phosphorusll~C=:::Jl1222441475197J nto n nds Map Search C Layers El He ~--- \~ C.f: 171fllt, St \ ) \ " ~. ~"' ...... .,. R•'*> l .. h.ro~, ~ z ..... ..,,, .. d ---j Identify Results Assessment Hydro Boundaries Latitude: 47.5061S Longitude: -12 2.20 66 5 1 listin g found ~i Name !!Paramete ~jW A SHJNGTO"'' • ~ , LAKEJ IBacteria . ~ ! Layers Cl He /---~ --= Datum: NAD83 HARN 128tt, St _\ __ A ~ ::> ~ .. ; s r.,.h_ s, .. -. i, •• . - ~ ~ 3 ! \ ~ .. .. ~-Identify Results \ "' " ,;; lrHt St " j (•'\· S l•d S, ~ w z . . i i .-,t .,.-6 ~\ t . ~ N( • ., •1 ~ . < )-- ( J // ~ ~.1ap S@arch C ;; . ; ·-Po• V ! <F' ............ ~ E.u t R~nton I_ H, IOI "n<t "-E , \ \ :.1.:1 APPENDIXG FLOW CONTROL BMPs I i j '4 ~"0 '' J :J ALTERNATIVE 2 OBTAIN EASEMENT AND ROUTE WEST BEl'WEEN HOMES TO MONROE AVE ~ 1-D -· ·. f 1·-·~ '.( .. ,_'( ) ~ ) -·"""T·-i~ / __ J ·-J ! : I j -·-·-·-·j OLYMPIA AVE. NE -I - RESERVOIR SUMMARY I ·1· 1' ~.-oy/) I i .f ! UNDER PHASE I, CONSTRUCT NEW 6.J MG REINFORCED CONCRETE RECTANGIJLAR RESERVOIR. THE PHASE I RESERVOIR MLL BE DESIGNED WITH A 2-STAGE Q\l[RfLOW SYSTEM TO ALLOW Tl,E RESERVOIR TO BE OPERATED AT TWO Dlff[RENT OVERFLOW ELEVAT10t6, THEREBY ALLOWNG THE TANKS TO 8( OPERATED IN CONJJNCTION WITH OR IN REPLACEI.IENT TO THE HISTING 435 ZONE RESERVORS CAPAOTY 6 J l.lG O «5 5' O.E (HLO ~45) 4.7 MG O 4398' OE. (HLD 05) DIMENSIONS: 255',170' FlNISHfLOOOELEVATI00:425.0'NOM. ROOfELEVATION·450.0'APPROX F1N1SHGRA0E:4JO'APPROX lH£PHASE1RESERVOIRIW._LBEPARTlTIONED'MTHSEPARATEINL£T,OJTL£T,DRAIN ,I.ND OYERFLOW S'l'STEMS. A l,l[lER V,1,ULT 'MLL BE ffiOVIDED FOR MONITORING INLET ANO OI.JT\.ET nows. THE RESERVOIR WLL Sf: PARTI ... LLY BURffD AND SCREENED WITH VEGETATION. AS PART Of THE ALTERNATJ\1[5 ANALYSIS, CONSIDERATION W,1.S ijj,'[N TO ,I. ORCULAR CONCRETE/STEEl RESERVOR HO~~R. DUE TO SITE CONSTRAINTS AND ST™-l WAT[RR[QUIREME!jTS.THES[ALTERNATl\li:Sl'£REDETERUINEDTOBEIMPRACTICAL RELOCATE EXISTING CITY RADIO r ANTENNA TO 565 ELEVATED TANK I PROPOSED 4351445 ZONE TRANSMISSION MAIN ALTERNATIVE TO REDUCE THE DEPTH OF TRANSMISSION MAIN PIP1ft3. ROUTE PIPING WITHIN MONROE AVE TO 12TH ST. INTERSECTION D / ~. ~ -~ --/ []DD Di G . i TEE FOR FUTURE 4351445 TO 565ZONE PUMP STATION 15.0' SETBACK LINE WATER MAIN SUM_~ARY A NEW xx' TRANSMISSION UAJN IS R[QUIRED TO CONNECT TH( PHASE I TANKTOTHEEXlSTING-4J5Z~E Tli[[XlSTINC4J5ZONEPIPINGWH111N N~ 12TH STREET IS ~RY DEEP AT THE POINT AT \IIHICH THE WATERMAIN LEAi{$ THE SITE, CREATING A MAJNlENANCE CHALLENGE FOO THE OTY TO MITICATt THS CHil.LLENGE, THE CITY COULD CONSTRUCT A NEW 435/-445 ZCN( TRANSMl~ON MAIN THAT WOW) DIT THE SITE TOWARDS THEWESTANDRUNWITHINMONRCEil.',{NUETOTHEINTERSECTIONWITH NE12THST. lHEELEVil.TIONATTHISINTERSECTIONISAPPROlOMATELY ATTHESAUEELEVil.TIONASTHERESER','01RFL00R,THERE:BYALL0'MNG THEMAINTOBE1NSTALLE0ATSTANOARD8URY0EPTH. THIS ALltRNATI~ WOULD REQUIRE THAT THE CITY ACOUIRE A NEW Eil.SEMENT AS PART Cf THE ALTERNATI~S ANALYSIS. CONSIDERATION WAS GlvrN TO COOSTRUCTINGTH[PHASE1Til.l«Y11THAHIGHERFIN1SHEDFLOOR ELEVATIONINOOOfRTO~SSTHEWATERMAINOEPTHISSUE, HO't.{YER THIS WAS DETEffl,IINEO TO BE IMPRACTICAL OVE TODrSTlNG SITE!Cf'OGRAPHYYMICHWOOI.OREOUIRETHATTHETANKB[ CONSTRUCTED ON FILL AND WOOLO SICNlflC/1.NTLY REDUCED T'rlE STOffAGE C!.PACITYCfTHEPROPOSEOT.i.NK STORM WATER SUMMARY UNDER PHASE 1, A BELOW-GRADE CONCRETE DETENTION VAUU lfllll BE REQUIRED FOR STo:lNWATER ANO RESERVOIR OVERFLOW THE VAULT 'MU BE P,'.RTITIONED WITH SEPARATE COI.LEC"TIONANODElENTIONSYSTEMSFl'.lR[ACH Of THE NORTH RENTON ii.ND HONEY CREE~ Bil.SINS. TI,[ VAULTS SHOULD BE DESIGNED TO ALLOW FORTHESY5TEMTOBEEXPAN0ED1NTHEFUTUREBASEOONFUTURESITE DE~LOPUENTANOSTORMWATERSTANDAROS. NDRJl::IRFNIOOH.+.SiNCIU REQU1R[0STORMCAPACITY.12,500CF REQUIRED OVERFLOW CAPACITY; 38,500 Cf (BASED ON ~.800 fl'M O 60 MINUTES) DIWENS10NS:!2Q'x3Q' HONEYCRHKRA51NCEll REQIJlREO STQR!,I CAPAOTY· 19,000 CF DIWENSIONS: 90'd0' TOTAi DETFNDOO V~l!I I Dllo4ENSIONS: 210'xJ0',12' (7~.600 CF) DETENTION VAULTBOTTCII ELEV: 4180' DETENTIONVAULTTOPELEV HOO" WATER OCPTH UNDER STORM CONDITIONS: J.5' (NORTH RENTON) -7' (HONEY CREEK) Wil.TER DEPTH UNDER OVERFLOW CONDITIONS: 11' (NORTH RENTON CELL ONLY) MA:CWATERDEP1"HUND£RST~+OVERF1.0WC0NDITIONS: 11'(B0THC£LLS) North Renton Permeable Subgrade Location: Approx. 0.090 AC LJ· • AL TER~ATIVE 1 REVISE EXISTING EASEMENT TO INCLUDE STORM AND ROUTE ".!:)RTH THROUGH RETIREMEt.. T CENTER 0 ARKl~G LOT INLET/OUTLET METER VAULT PROPOSED VEGETATION ON FILL SLOPE ~:Wh/::~4 -1 30 ~~~~~~'.0N . ' ELECTRICAL I CONTROL SUMMARY SITE IMPROVEMENTS AS PART OF" PHASE: 1, A NEW 215 KW QU1£1-S1TE, OUTDOOR ENG1NE GENERATOR 'MLL SE INSTALLED TO REPLACE THE EXISTING 125 kW [NGIN£ GENERATOR THE EXISTING EG ANO BUILDING WIL'. BE REMOVED THE 275 KW EG 'MLL 6£ TEMPOffARILY LOCATED ON TflE EX1STING EC BUILDING SlAB ANO A NEW ~-POI.[ SH£LrtR 'MLL BE CONSTRUCTED TO SHIHO THE EC FROI.I Ril.lN AND SNl'.lW A FUH T/1.NK Cil.PA6l[ Of" HOI.DING A 5 DAY iUEL SUPPLY ~T FULL LOAD OPERATION SHALL BE PR0\'10ED CONSTRUCT NEW ACCESS ROil.O ii.NO YEttlCLE GATE THAT WILL BtCOMEPR1MARYACC£SSPOINTF00FINAJ..SITE PROPOSED SITE PLAN •-1":;)\J = 1 11 ~~ :- ~?. ~'? n ~ t· 0 ~ z • ~ Q • I r/) ! l ~ ~ ~ " ' ~ f '' I ~ . ~ II ... w ~ ::c Q. z :3 Q. MI\X2HW[TYP) 6'FREEORAINING BASE EXISTINGNATNE MATERIAL TYPICAL ROAD SECTION (INFILTRATION) NlS %VARIES ----- IMPER!AEABLEMATERIALEVENlYSPACEDTO PREVENTFLOWALONGSUBGRADE SECTION A NlS CITY OF RENTON HIGHLANDS 435 ZONE RESERVOIRS AND ENGINE GENERATOR \DATA\11Gff-D-DET-PAY Road Infiltration Calculations Retention/Detention Facility Type of Facility: Gravel Infiltration Trench Facility Length: 200.00 ft Facility Width: 15.00 ft Facility Area: 3000. sq. ft Effective Storage Depth: 0.15 ft Stage O Elevation: 0.00 ft Storage Volume: 135. cu. ft Vertical Permeability: 82.90 min/in Permeable Surfaces: Bottom Riser Head: 0.15 ft Riser Diameter: 12.00 inches Top Notch Weir: None Outflow Rating Curve: None Stage Elevation Storage Discharge (ft) (ft) (cu. ft) (ac-ft) (cfs) 0.00 0.00 0. 0.000 0.000 0.01 0.01 9. 0.000 0.000 0.02 0.02 18. 0.000 0.000 0.03 0.03 27. 0.001 0.000 0.04 0.04 36. 0.001 0.000 0.05 0.05 45. 0.001 0.000 0.06 0.06 54. 0.001 0.000 0.07 0.07 63. 0.001 0.000 0.08 0.08 72. 0.002 0.000 0.09 0.09 81. 0.002 0.000 0.10 0.10 90. 0.002 0.000 0.11 0.11 99. 0.002 0.000 0.12 0.12 108. 0.002 0.000 0.13 0.13 117. 0.003 0.000 0.14 0.14 126. 0.003 0.000 0.15 0.15 135. 0.003 0.000 0.25 0.25 135. 0.003 0.308 0.35 0.35 135. 0.003 0. 871 0.45 0.45 135. 0.003 1. 600 0.55 0.55 135. 0.003 2.390 0.65 0.65 135. 0.003 2.670 0.75 0.75 135. 0.003 2.930 0.85 0.85 135. 0.003 3.160 0.95 0.95 135. 0.003 3.380 1. 05 1. 05 135. 0.003 3.590 1.15 1.15 135. 0.003 3.780 1.25 1.25 135. 0.003 3.970 1. 35 1. 35 135. 0.003 4.140 1.45 1.45 135. 0.003 4.310 1. 55 1. 55 135. 0.003 4.470 1. 65 1. 65 135. 0.003 4.630 1. 75 1. 75 135. 0.003 4.780 1. 85 1. 85 135. 0.003 4.930 Percolation (cfs) 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 1.95 1. 95 135. 0.003 5.070 0.05 2.05 2.05 135. 0.003 5.210 0.05 Hyd Inflow Outflow Peak Storage Target Cale Stage Elev (Cu-Ft) (Ac-Ft) 1 0.03 ******* 0.00 0.00 0.00 0. 0.000 2 0.02 ******* 0.00 0.00 0.00 0. 0.000 3 0.02 ******* 0.00 0.00 0.00 0. 0.000 4 0.02 ******* 0.00 0.00 0.00 0. 0.000 5 0.02 ******* 0.00 0.00 0.00 0. 0.000 6 0.02 ******* 0.00 0.00 0.00 0. 0.000 7 0.02 ******* 0.00 0.00 0.00 0. 0.000 8 0.01 ******* 0.00 0.00 0.00 0. 0.000 ---------------------------------- Route Time Series through Facility Inflow Time Series File:dev.tsf Outflow Time Series File:rdout Inflow/Outflow Analysis Peak Inflow Discharge: 0.033 CFS at 6:00 on Jan 9 in Year 8 Peak Outflow Discharge: 0.000 CFS at 6:00 on Jan 9 in Year 8 Peak Reservoir Stage: 0.00 Ft Peak Reservoir Elev: 0.00 Ft Peak Reservoir Storage: 0. Cu-Ft 0.000 Ac-Ft Flow Duration from Time Series File:rdout.tsf Cutoff Count Frequency CDF Exceedence_Probability CFS % % % 0.000 61320 100.000 100.000 0.000 O.OOOE+OO 0.000 0 0.000 100.000 0.000 O.OOOE+OO 0.000 0 0.000 100.000 0.000 O.OOOE+OO 0.000 0 0.000 100.000 0.000 O.OOOE+OO 0.000 0 0.000 100.000 0.000 O.OOOE+OO 0.000 0 0.000 100.000 0.000 0.000E+OO 0.000 0 0.000 100.000 0.000 O.OOOE+OO 0.000 0 0.000 100.000 0.000 O.OOOE+OO 0.000 0 0.000 100.000 0.000 O.OOOE+OO 0.000 0 0.000 100.000 0.000 O.OOOE+OO 0.000 0 0.000 100.000 0.000 0.000E+OO 0.000 0 0.000 100.000 0.000 O.OOOE+OO 0.000 0 0.000 100.000 0.000 O.OOOE+OO 0.000 0 0.000 100.000 0.000 O.OOOE+OO 0.000 0 0.000 100.000 0.000 O.OOOE+OO 0.000 0 0.000 100.000 0.000 O.OOOE+OO 0.000 0 0.000 100.000 0.000 O.OOOE+OO 99999.99 0 0.000 100.000 0.000 O.OOOE+OO 0.000 0 0.000 100.000 0.000 O.OOOE+OO 0.000 0 0.000 100.000 0.000 O.OOOE+OO 0.000 0 0.000 100.000 0.000 0.000E+OO 0.000 0 0.000 100.000 0.000 O.OOOE+OO 0.000 0 0.000 100.000 0.000 O.OOOE+OO 0.000 0 0.000 100.000 0.000 O.OOOE+OO 0.000 0 0.000 100.000 0.000 O.OOOE+OO 0.000 0 0.000 100.000 0.000 O.OOOE+OO 0.000 0 0.000 100.000 0.000 O.OOOE+OO 0.000 0 0.000 100.000 0.000 O.OOOE+OO 0.000 0 0.000 100.000 0.000 O.OOOE+OO 0.000 0 0.000 100.000 0.000 O.OOOE+OO 0.000 0 0.000 100.000 0.000 O.OOOE+OO 0.000 0 0.000 100.000 0.000 O.OOOE+OO 99999.99 0 0.000 100.000 0.000 O.OOOE+OO 99999.99 0 0.000 100.000 0.000 O.OOOE+OO 0.000 0 0.000 100.000 0.000 O.OOOE+OO 0.000 0 0.000 100.000 0.000 O.OOOE+OO Flow Frequency Analysis Time Series File:rdout.tsf Project Location:Sea-Tac ---Annual Peak Flow Rates--------Flow Frequency Analysis------- Flow Rate Rank Time of Peak --Peaks --Rank Return Prob (CFS) (CFS) (ft) Period 0.000 1 10/01/00 0:00 0.000 0.00 1 100.00 0.990 0.000 2 10/01/01 0:00 0.000 0.00 2 25.00 0.960 0.000 3 10/01/02 0:00 0.000 0.00 3 10.00 0.900 0.000 4 10/01/03 0:00 0.000 0.00 4 5.00 0.800 0.000 5 10/01/04 0:00 0.000 0.00 5 3.00 0.667 0.000 6 10/01/05 0:00 0.000 0.00 6 2.00 0.500 0.000 7 10/01/06 0:00 0.000 0.00 7 1. 30 0.231 0.000 8 10/01/07 0:00 0.000 0.00 8 1.10 0.091 Computed Peaks 0.000 0.00 50.00 0.980 Dev.pks Road Infiltration -Flow Frequency Analysis Time series File:dev.tsf Project Location:sea-Tac ---Annual Peak Flow Rates--------Flow Frequency Analysis------- Time of Peak --Peaks --Rank Return Prob Flow Rate Rank (CFS) (CFS) Period 0.017 7 2/09/01 2 00 0.033 1 100.00 0.990 0.015 8 1/05/02 16 00 0.025 2 25.00 0.960 0.020 3 12/08/02 18 00 0.020 3 10.00 0.900 0.017 6 8/26/04 2 00 0.020 4 5.00 0.800 0.020 4 10/28/04 16 00 0.018 5 3.00 0.667 0.018 5 1/18/06 16 00 0.017 6 2.00 0.500 0.025 2 10/26/06 0 00 0.017 7 1.30 0.231 0.033 1 1/09/08 6 00 0.015 8 1.10 0.091 computed Peaks 0.030 50.00 0.980 Page 1 rdout.pks Road Infiltration -Flow Frequency Analysis Time series File:rdout.tsf Project Location:sea-Tac ---Annual Peak Flow Rates--- Rank Time of Peak -----Flow Frequency Analysis------- Flow Rate (CFS) 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 computed Peaks 1 10/01/00 0 00 2 10/01/01 0 00 3 10/01/02 0 00 4 10/01/03 0 00 5 10/01/04 0 00 6 10/01/05 0 00 7 10/01/06 0 00 8 10/01/07 0 00 --Peaks --Rank Return Prob (CFS) (ft) Period 0.000 0.00 1 100.00 0.000 0.00 2 25.00 0.000 0.00 3 10.00 0.000 0.00 4 5.00 0.000 0.00 5 3.00 0.000 0.00 6 2.00 0.000 0.00 7 1.30 0.000 0.00 8 1.10 0.000 0.00 50.00 Page 1 0.990 0.960 0.900 0.800 0.667 0. 500 0.231 0.091 0.980 CURB CURB~ ~ CURB CUT ELEVATION NTS 6' COMPACTED CRUSHED SURFACING BASE COURSE t SWALE EXISTING ASPHALT CURB CUT PLAN PROPOSED CURB ANDGUffiRPER PLANS AND DETAILS NTS _....J--------8' -------< PROVIOE6-INCH/~·----- THICK TOPSOIL SUBGRADE (EXISTING PROPOSED SIDEWALK PER PLANS AND DETAILS OR FILL) PER PLANS FRONTAGE IMPROVEMENTS DETAIL NTS CITY OF RENTON HIGHLANDS 435 ZONE RESERVOIRS AND ENGINE GENERATOR \,OATA~--f'AV APPENDIXH KCRTS )/ ---__ l MONROE AV£ NE 565ZONE_~ -----=---=------;:~=-..:=__ ,o' ROW _L ---~--_J -0·· DI W ---- 'x>S/':],t _l 1: •--=J I _J_ G-----S,----ss----S,----S,---ss----ss----ss----ss----•--e-ss----ss----ss----ss----,s--_,, ____ ,, ____ ,, ____ ,, ___ _ .e.......--..... ,., ____ ... _ ..... __ ----. 565Zc»IE --,rOI w----12"0, ( I/ fJ 1 '\! '... CONNECT TO EXISTING 16" DI WATER MAIN ANO It t '. ~ RE PURPOSE EXISTING MAIN BETWEEN MONROE AVE. a ;_ AND SUNSET BLVD FOR ROPS FORCEMAIN, SEE --1 I Johns Creek TDA I ~_I ·-·~GNO C11 FOR CONTINUATION ,- I rt-I _JI ,;,,i ABANDON EXISTING PORTION OF DEEP 16" DI WATER ' I : I ~ ::rn:tt--.. MAIN TO MONROE AVE , INSTALL PROPOSED 16" ROPS FORCE MAIN OVER TOP OF EXISTING MAIN ----.,_,-.,, ''-'~=~' I : I 1, Existing Project Site to Vault _ _ : ' f : ~ Impervious (Reservoirs & Buildings). 0.48 AC I I I, l Ii, nil Grass (Landscaping): 0.88 AC I · '.. • _ ,\ ' ~ '",' / , I , Ii 1-I <, , ""I a " ""°'"''"'-' ~ ~~,c. c j ~'.">. <.C~I ~·,~~Cc,~~L~':c'';;::24,~~ .;~ , : ; 1.~. ,~~~~\ l ,,_ ---~--@" ABANDONED QISH 112 MC 4:V, ZCH CQIQEIE Bt:'.iB\ffi O\OF\.OWELEV. 439.8' {HLD 43S) ROOF' El(V 448.9' (NCII) flOCJIEL£V.425.9'(NCII.)' CIMEN9{WS:t51'x155' EXISJlfG2QNG4\5KM ~ =EL£V098' (H1D4J5)~ R()(J' nrv. 448.5' (NCI!.) fl~ O.Cv. 421.5' {NCM.)' OIIOSIOMS: 122' • 2JO' ,,, 'l, "· INTFRCFPT FXISTiNG RF$FR,C'l:R nRAl~l AND OVERFLOW A~C ROUTE TO PROPOSED S"."JRM DRMN MA~hOLE GAL STORMWA TER ANO RESERVOI~ OVERFlOW DETENTION VAULT AND PUMP STATIONS SEE DWG NO. S05 FOR AOOmONAL INFORMATION ROOF ELEV. 429.0' (NOM.) FLOOR ELEV. 418.a (NOM.) DIMENSIONS 210' x 'YJ RESE '(, 1)1::{ ::. /E~"L'J',', f''~11)(., l>.'JJ ~IR GAe' srn::c-_1;;:E fl(S[;;:vo1;;:o[S-iJ)Rl;'J,\TJ(,'JS-:,-,.J\.:.\.:: CETEt.70N '/Al,LT=AR"'-Si. ,9E~:=: . ,:;.;:.:,::;::: ~Ro~osEC ,2· uc-:-cw1'...:N ] ~~-=----,o SCHPIGE PIPE T'J H.::":::·• -Vi.~•, e:,::,•, PRO~l!Si-"C f<F::-,:'i:s'.<) ~ ;O,)fl~G )~'Sr--. "l'!Jc:-M,ECO'; pp ,"r / ') •,_, ' {!'_" " '1- i ~ !j ' 11 .! Tli L,_ .ulr !" ,,, 1: 1 ,/ 'o ~ ,Dt,Hl90,' :/ l ::~o:::csrn ASPH;.L T ,1,~C.ES'i ROAC ;:--1"REE-L•;;:.:a.r..r..::OS••SE PROPOSED 4351445 CONCRETE RESERVOIR CAPACllY. 6.3 MG@44S.5' O.E. (HLD 445) CAPACfTY· 4.7 MG@439.8' O.E (HLO 435) SEE DWG NO. S01 FOR ADDITIONAL INFORMATION OVERFLOW ELEV 439 8'1445 s· ROOF ELEV. 4511.D' (NOM.) FLOOR ELEV 4250'(NOMJ DIMENSIONS 174' x 259' PROPOSED INLET/OUTLET PIPING, SEE DWG NO M01 FOR AOOfTIONAL INFORMATION ·~ ·;,tl)I:: 'Rl::!::·CK-"i'fl'K; T ,,p ~'F ;,:;.:i:-'. SF:' ~·.:FRGC:r--.C" C !ERFLC>,\ 3~~·", ~·_:~: ',~'L TISATit,G '.:J3GR,\}E l&d} '._ '.?,,~ ---~ -> '-,., .. ,,,,''.<-cHqc:• ' ., ===, --. _ _ _.:::..__ __ , .:__:::_~~-.....,,,._L'.:'.--~ '." C~C~~---:o '~Cffi---~,--:oi---:o c;,,,.-~ ,,, ----., -·-·if·-·-·-·-·--·-r-·-·-·-·--,·-·----·-·-·--·---·---·----;r-· ---- 1 -, ---·f---+ l . --./ ... ,, ... _ I 11 I , "'' ,, """' 1 1 j ! ,c I / i' ,, --/ I - PROPOSED ~R~INAGE PLAN=•- I ~ §: ~~ z ~i~ ~ !,.,~.~ w ~ ~-~ Cl 1:11; ~.~ ~ ~~~ ~ ;,.,"'l C !::;~~ C u"I!~-w ""1 :i!:; "' :t:"I! 0 ~ ~ ::z:: a: a. • s C' z ~ (.!) ~ if) ~ ul ~ 0 .1~ ~ ! z ~ ~ ,:J B ,ul : cc +-o. _'_j I I I I ! 1111 111 SCALE. SHOWN ~ DAA>IO'/>'Gl$FIJ/..lS('.,IHWIJf~ s,IRI.IEASURES:!' ,,----,-,,,,,,, C10 i 10 ,.. ,, Flow Frequency Analysis Time Series File;predev.tsf Project Location;sea-Tac ---Annual Peak Flow Rates--- Flow Rate Rank Time of Peak (CFS) 0.269 4 2/09/01 2 00 0.179 7 1/05/02 16 00 0. 328 2 2/27/03 7 00 0.148 8 8/26/04 2 00 0.187 6 10/28/04 16 00 0.283 3 1/18/06 16 00 0.260 5 11/24/06 3 00 0. 579 1 1/09/08 6 00 computed Peaks predev.pks -----Flow Frequency Analysis------- --Peaks Rank Return Prob (CFS) Period 0. 579 1 100.00 0.990 0.328 2 25.00 0.960 0.283 3 10.00 0.900 0.269 4 5.00 0.800 0.260 5 3.00 0.667 0.187 6 2.00 0. 500 0.179 7 1. 30 0.231 0.148 8 1.10 0.091 0.495 50.00 0.980 Page 1 Flow Frequency Analysis Time series File:bypass.tsf Project Location:sea-Tac ---Annual Peak Flow Rates--- Flow Rate Rank Time of Peak (CFS) 0.024 4 2/09/01 2 00 0.016 7 1/05/02 16 00 0.030 2 2/27/03 7 00 0.013 8 8/26/04 2 00 0.016 6 10/28/04 16 00 0.025 3 1/18/06 16 00 0.023 5 11/24/06 3 00 0.053 1 1/09/08 6 00 Computed Peaks Byapss.pks -----Flow Frequency Analysis------- --Peaks --Rank Return Prob (CFS) Period 0.053 1 100.00 0.990 0.030 2 25.00 0.960 0.025 3 10.00 0.900 0.024 4 5.00 0.800 0.023 5 3.00 0.667 0.016 6 2.00 0. 500 0.016 7 1. 30 0.231 0.013 8 1.10 0.091 0.045 50.00 0.980 Page 1 Flow Frequency Analysis Time Series File:dev.tsf Project Location:sea-Tac ---Annual Peak Flow Rates--- Flow Rate Rank Time of Peak (CFS) 0.382 6 2/09/01 2 00 0.303 8 1/05/02 16 00 0.461 3 2/27/03 7 00 0.318 7 8/26/04 2 00 0.385 5 10/28/04 16 00 0.404 4 1/18/06 16 00 0.462 2 10/26/06 0 00 0.783 1 1/09/08 6 00 computed Peaks dev.pks -----Flow Frequency Analysis------- --Peaks Rank Return Prob (CFS) Period 0.783 1 100.00 0.990 0.462 2 25.00 0.960 0.461 3 10.00 0.900 0.404 4 5.00 0.800 0.385 5 3.00 0.667 0.382 6 2.00 0.500 0. 318 7 1. 30 0.231 0.303 8 1.10 0.091 0.676 50.00 0.980 Page 1 Johns Creek -Retention/Detention Facility Type of Facility: Detention Vault Facility Length: 35.00 ft Facility Width: 30.00 ft Facility Area: 1050. sq. ft Effective Storage Depth: 8.00 ft Stage O Elevation: 418.00 ft Storage Volume: 8400. cu. ft Riser Head: 8.00 ft Riser Diameter: 18.00 inches Number of orifices: 2 Full Head Pipe Orifice # Height (ft) 0.00 6.00 Diameter Discharge Diameter 1 2 Top Notch Weir: Outflow Rating Curve: Stage Elevation (in) 1. 77 2.78 None None Storage (CFS) (in) 0.240 0.297 6. 0 Discharge (ft) (ft) (cu. ft) (ac-ft) (cfs) 0.00 418.00 0. 0.000 0.000 0.02 418.02 21. 0.000 0.012 0.04 418.04 42. 0.001 0.016 0.06 418.06 63. 0.001 0.020 0.07 418.07 74. 0.002 0.023 0.09 418.09 95. 0.002 0.026 0.11 418.11 116. 0.003 0.028 0.13 418.13 137. 0.003 0.030 0.15 418.15 158. 0.004 0.033 0.28 418.28 294. 0.007 0.045 0.42 418.42 441. 0.010 0.055 0.55 418.55 578. 0.013 0.063 0.69 418.69 725. 0.017 0.070 0.83 418.83 872. 0.020 0.077 0.96 418. 96 1008. 0.023 0.083 1.10 419.10 1155. 0.027 0.089 1.23 419.23 1292. 0.030 0.094 1.37 419.37 1439. 0.033 0.099 1.50 419.50 1575. 0.036 0.104 1. 64 419.64 1722. 0.040 0.109 1. 77 419.77 1859. 0.043 0 .113 1. 91 419.91 2006. 0.046 0 .117 2.05 420.05 2153. 0.049 0.121 2.18 420.18 2289. 0.053 0.125 2.32 420.32 2436. 0.056 0.129 2.45 420.45 2573. 0.059 0.133 2.59 420.59 2720. 0.062 0.137 2.72 420.72 2856. 0.066 0.140 2.86 420.86 3003. 0.069 0.143 Percolation (cfs) 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 2.99 420.99 3140. 0.072 0.147 0.00 3 .13 421.13 3287. 0.075 0.150 0.00 3.27 421.27 3434. 0.079 0.153 0.00 3.40 421. 40 3570. 0.082 0.156 0.00 3.54 421.54 3717. 0.085 0.160 0.00 3.67 421. 6 7 3854. 0.088 0.163 0.00 3.81 421.81 4001. 0.092 0.166 0.00 3.94 421.94 4137. 0.095 0.169 0.00 4.08 422.08 4284. 0.098 0.171 0.00 4.22 422.22 4431. 0.102 0.174 0.00 4.35 422.35 4568. 0.105 0.177 0.00 4.49 422.49 4715. 0.108 0.180 0.00 4.62 422.62 4851. 0 .111 0.182 0.00 4.76 422.76 4998. 0 .115 0.185 0.00 4.89 422.89 5135. 0 .118 0.188 0.00 5.03 423.03 5282. 0.121 0.190 0.00 5.16 423.16 5418. 0.124 0.193 0.00 5.30 423.30 5565. 0.128 0.195 0.00 5.44 423.44 5712. 0.131 0.198 0.00 5.57 423.57 5849. 0.134 0.200 0.00 5.71 423.71 5996. 0.138 0.203 0.00 5.84 423.84 6132. 0.141 0.205 0.00 5.98 423.98 6279. 0.144 0.207 0.00 6.00 424.00 6300. 0.145 0.208 0.00 6.03 424.03 6332. 0.145 0.210 0.00 6.06 424.06 6363. 0.146 0.217 0.00 6.09 424.09 6395. 0.147 0.227 0.00 6.12 424.12 6426. 0.148 0.241 0.00 6.14 424.14 6447. 0.148 0.258 0.00 6.17 424.17 6479. 0.149 0.279 0.00 6.20 424.20 6510. 0.149 0.303 0.00 6.23 424.23 6542. 0.150 0.313 0.00 6.26 424.26 6573. 0.151 0.320 0.00 6.40 424.40 6720. 0.154 0.347 0.00 6.53 424.53 6857. 0.157 0.370 0.00 6.67 424.67 7004. 0.161 0.391 0.00 6.80 424.80 7140. 0.164 0.410 0.00 6.94 424.94 7287. 0.167 0.427 0.00 7.07 425.07 7424. 0.170 0.443 0.00 7.21 425.21 7571. 0 .174 0.459 0.00 7.35 425.35 7718. 0 .177 0.474 0.00 7.48 425.48 7854. 0.180 0.488 0.00 7.62 425.62 8001. 0.184 0.501 0.00 7.75 425.75 8138. 0.187 0.514 0.00 7.89 425.89 8285. 0.190 0.527 0.00 8.00 426.00 8400. 0.193 0.537 0.00 8.10 426.10 8505. 0.195 1. 010 0.00 8.20 426.20 8610. 0.198 1. 860 0.00 8.30 426.30 8715. 0.200 2.960 0.00 8.40 426.40 8820. 0.202 4.270 0.00 8.50 426.50 8925. 0.205 5.740 0.00 8.60 426. 6 0 9030. 0.207 7.180 0.00 8.70 426.70 9135. 0.210 7. 710 0.00 8.80 426.80 9240. 0.212 8.210 0.00 8.90 426.90 9345. 0.215 8.680 0.00 9.00 427.00 9450. 0.217 9.130 0.00 9.10 427.10 9555. 0.219 9.550 0.00 9.20 427.20 9660. 0.222 9.950 0.00 9.30 427.30 9765. 0.224 10.340 0.00 9.40 427.40 9870. 0.227 10. 720 0.00 9.50 427.50 9975. 0.229 11.080 0.00 9.60 427.60 10080. 0.231 11.430 0.00 9.70 427.70 10185. 0.234 11. 760 0.00 9.80 427.80 10290. 0.236 12.090 0.00 9.90 427.90 10395. 0.239 12.410 0.00 Hyd Inflow Outflow Peak Storage Stage Elev 1 0.78 0.53 7.93 425.93 2 0.38 0.22 6.06 424.06 3 0.38 0.24 6.12 424.12 4 0.40 0.26 6.15 424.15 5 0.46 0.19 4.82 422.82 6 0.38 0.15 3.16 421.16 7 0.30 0.12 2.10 420.10 8 0.32 0 .11 1. 74 419.74 Hyd R/D Facility Tributary Reservoir Outflow Inflow Inflow 1 0.53 0.05 ******** 2 0.22 0.02 ******** 3 0.24 0.02 ******** 4 0.26 0.03 ******** 5 0.19 0.03 ******** 6 0.15 0.02 ******** 7 0.12 0.02 ******** 8 0 .11 0.01 ******** Route Time Series through Facility Inflow Time Series File:dev.tsf Outflow Time Series File:rdout POC Time Series File:dsout Inflow/Outflow Analysis Peak Inflow Discharge: 0.783 CFS Peak Outflow Discharge: 0.530 CFS Peak Reservoir Stage: 7.93 Ft Peak Reservoir Elev: 425.93 Ft (Cu-Ft) (Ac-Ft) 8322. 0.191 6365. 0.146 6430. 6453. 5063. 3314. 2203. 1832. POC Outflow Target Cale 0.58 0.56 ******* 0.23 0.28 0.26 ******* 0.28 ******* 0.20 0.19 0.16 ******* 0.13 ******* 0.12 at 6:00 on Jan at 10:00 on Jan 0.148 0.148 0 .116 0.076 0.051 0.042 9 in 9 in Peak Reservoir Storage: 8322. Cu-Ft 0.191 Ac-Ft Add Time Series:bypass.tsf Year 8 Year 8 Peak Summed Discharge: 0.556 CFS at 9:00 on Jan 9 in Year 8 Point of Compliance File:dsout.tsf Flow Frequency Analysis Time Series File:rdout.tsf Project Location:Sea-Tac ---Annual Peak Flow Rates--- Flow Rate Rank Time of Peak (CFS) 0.244 3 2/09/01 19:00 0.122 7 1/05/02 18:00 0.186 5 2/27/03 10:00 0 .112 8 8/23/04 21:00 0.150 6 10/28/04 19:00 0.262 2 1/18/06 21:00 0.218 4 11/24/06 6:00 0.530 1 1/09/08 10:00 Computed Peaks Flow Frequency Analysis Time Series File:dsout.tsf Project Location:Sea-Tac ---Annual Peak Flow Rates--- Flow Rate Rank Time of Peak (CFS) 0.260 3 2/09/01 19:00 0.129 7 1/05/02 17:00 0.197 5 2/27/03 9:00 0 .116 8 8/23/04 20:00 0.158 6 10/28/04 19:00 0.278 2 1/18/06 21:00 0.233 4 11/24/06 6:00 0.556 1 1/09/08 9:00 Computed Peaks Route Time Series through Facility Inflow Time Series File:dev.tsf Outflow Time Series File:rdout POC Time Series File:dsout Inflow/Outflow Analysis Peak Inflow Discharge: 0. 783 Peak Outflow Discharge: 0.530 Peak Reservoir Stage: 7.93 Peak Reservoir Elev: 425.93 Peak Reservoir Storage: 8322. -----Flow Frequency Analysis------- --Peaks --Rank Return Prob (CFS) (ft) Period 0.530 7.93 1 100.00 0.990 0.262 6.15 2 25.00 0. 960 0.244 6.12 3 10.00 0.900 0.218 6.06 4 5.00 0.800 0.186 4.82 5 3.00 0.667 0.150 3.15 6 2.00 0.500 0.122 2.10 7 1.30 0.231 0 .112 1. 74 8 1.10 0.091 0.441 7.05 50.00 0.980 -----Flow Frequency Analysis------- --Peaks Rank Return Prob (CFS) Period 0.556 1 100.00 0.990 0.278 2 25.00 0.960 0.260 3 10.00 0.900 0.233 4 5.00 0.800 0.197 5 3.00 0.667 0.158 6 2.00 0.500 0.129 7 1.30 0.231 0.116 8 1.10 0.091 0.463 50.00 0.980 CFS at 6:00 on Jan 9 in Year 8 CFS at 10:00 on Jan 9 in Year 8 Ft Ft Cu-Ft 0.191 Ac-Ft Add Time Series:bypass.tsf Peak Summed Discharge: 0.556 CFS at 9:00 on Jan 9 in Year 8 Point of Compliance File:dsout.tsf Flow Frequency Analysis Time Series File:rdout.tsf Project Location:Sea-Tac ---Annual Peak Flow Rates--- Flow Rate Rank Time of Peak (CFS) -----Flow Frequency Analysis------- --Peaks --Rank Return Prob (CFS) (ft) Period 0.244 3 2/09/01 19:00 0.530 7.93 1 100.00 0.990 0.122 7 1/05/02 18:00 0.262 6.15 2 25.00 0. 960 0.186 5 2/27/03 10:00 0.244 6.12 3 10.00 0.900 0 .112 8 8/23/04 21:00 0.218 6.06 4 5.00 0.800 0.150 6 10/28/04 19:00 0.186 4.82 5 3.00 0.667 0.262 2 1/18/06 21:00 0.150 3.15 6 2.00 0.500 0.218 4 11/24/06 6:00 0.122 2.10 7 1. 30 0.231 0.530 1 1/09/08 10:00 0 .112 1. 74 8 1.10 0 .091 Computed Peaks 0.441 7.05 50.00 0.980 Flow Frequency Analysis Time Series File:dsout.tsf Project Location:Sea-Tac ---Annual Peak Flow Rates--------Flow Frequency Analysis------- Flow Rate Rank Time of Peak --Peaks Rank Return Prob (CFS) (CFS) Period 0.260 3 2/09/01 19:00 0.556 1 100.00 0.990 0.129 7 1/05/02 17:00 0.278 2 25.00 0.960 0.197 5 2/27/03 9:00 0.260 3 10.00 0.900 0 .116 8 8/23/04 20:00 0.233 4 5.00 0.800 0.158 6 10/28/04 19:00 0.197 5 3.00 0.667 0 .278 2 1/18/06 21:00 0.158 6 2.00 0.500 0.233 4 11/24/06 6:00 0.129 7 1.30 0.231 0.556 1 1/09/08 9:00 0 .116 8 1.10 0 .091 Computed Peaks 0.463 50.00 0.980 Flow Frequency Analysis Time series File:rdout.tsf Project Location:Sea-Tac ---Annual Peak Flow Rates--- Flow Rate Rank Time of Peak (CFS) 0.244 3 2/09/0119 00 0.122 7 1/05/02 18 00 0.186 5 2/27/03 10 00 0.112 8 8/23/04 21 00 0.150 6 10/28/04 19 00 0.262 2 1/18/06 21 00 0.218 4 11/24/06 6 00 0.530 1 1/09/08 10 00 computed Peaks rdout.pks -----Flow Frequency Analysis------- --Peaks --Rank Return Prob (CFS) (ft) Period 0.530 7.93 1 100.00 0.990 0.262 6.15 2 25.00 0.960 0.244 6.12 3 10.00 0.900 0.218 6.06 4 5.00 0.800 0.186 4.82 5 3.00 0.667 0.150 3.15 6 2.00 o. 500 0.122 2.10 7 1. 30 0.231 0.112 1. 74 8 1.10 0.091 0.441 7.05 50.00 0.980 Page 1 Flow Frequency Analysis Time series File:dsout.tsf Project Location:sea-Tac ---Annual Peak Flow Rates--- Flow Rate Rank Time of Peak (CFS) 0.260 3 2/09/01 19 00 0.129 7 1/05/02 17 00 0.197 5 2/27/03 9 00 0.116 8 8/23/04 20 00 0.158 6 10/28/04 19 00 0.278 2 1/18/06 21 00 0.233 4 11/24/06 6 00 0.556 1 1/09/08 9 00 computed Peaks dsout.pks -----Flow Frequency Analysis------- --Peaks --Rank Return Prob (CFS) Period 0. 556 1 100.00 0.990 0.278 2 25.00 0.960 0.260 3 10.00 0.900 0.233 4 5.00 0.800 0.197 5 3.00 0.667 0.158 6 2.00 0. 500 0.129 7 1. 30 0.231 0.116 8 1.10 0.091 0.463 50.00 0.980 Page 1 Johns Creek Peak Rate Flow Control Standards -Matching Developed Conditions to Existing-KCRTS Modeling -·· ---.. -·--.---.1: --··- • ....,,"l.:,.~'Jll'li'l~~-:,~ ,,'lf."~.'i'-·.-;-z.~·:"r!·,,-.,,,ir-·i!, ~·= .. --~, -:~a~._ Return Period 2 5 10 20 50 100 100 0 rd out pks m Sea-Tac • dsoutpks 0 predev pks 0 R • 0 "' fii u. 8. .. I 0 ~ ft! 0 .c I • <> 0 0 • 0 "' 5 0 • 00 0 --• 0 0 0 • 0 0 • 0 t ,0-1 1 2 5 10 20 30 40 50 60 70 80 90 95 98 99 Cumulative Probability ----5' J1 W ----B' r.• W -- MONROE ,fl'£ NE ,o' ROW 56SZONi m·=-- CONNECT TO EXISTING 16" 01 WATER MAIN ANO REPURPOSE EXISTING MAIN BETWEEN MONROE AVE. ANO SUNSET BlVO. FOR ROPS FORCEMAIN, SEE OWGNO C11 FOR CONTINUATION ABANDON EXISTING PORTION OF DEEP 16" DI WATER fl[1 ~ MAINTOMONROEAI/E INSTALLPROPOSE016" ROPS FORCEMAIN OVER TOf> OF EXISTING MAIN I~-I l • I ---a ~---;-:.::---:=_::-·_:_g-~,)::-=-~--a··J,,. -!~----·-------__l ----------~ --__J___ ---- -e· u * ----e r, ~ ----~· Ji w - -,.;~ ZOt.C ~---ss----ss----s,-___ ,, ___ ,, ____ ,, ____ ,, ____ ,, ____ ,._ __ 9_,, ____ ,, ____ ,, ____ ,, ____ ,, ___ ,, ____ ,. ____ ,, ____ ,, ___ _ .,,__...__ '~-"'-"'-·-··~--~-·~·""·---~JQH£ --!l"O! W ----12"0, r -r-r -r 7- / 1 ri,;- . I ! I: ~, Honey Creek ~DALJ ,ws" '"" I j ccRCF',,;.1;, R.-::,n: TO NOR,. --1 I : I ; mv:w,0,',M',1&,i:r,' ' : ~'',,"':"' 1 ; I , OVERFLOW ELEV 5691' I ·,:_l .. _ .. _\1" ,.. I r l 1 ' (HLD 565) ,~ .. bl )Y) d.l I I t;. RWELEV576'(APPROX) j ." UC-. BASE ELEV 4J4'/APPROX) I J r,I I ', •. "\\ ' DIMEN~ONS 66.5 DIA l I I '-. ''_,, "', / (<PPRO<) l J' ,t I ' ·, > / ~,.. <:f-•r'I _,, v -'' LJ/t" " " ," -'c "" ' "== ~ ,--=e. cc:'-. •,. , . _ _);•. , ~ • , ,,;',!i::,'i;ck~; -~':-~;;~! • ' f.: C, -, ,. =~~. ;;.s5;' 0 r r ~\ 1 ----~--ef -,,,i /·~'· +-'e, 1'./TER8EPT E.<15,.II.IG RESE! Vr:IR DRAIJI; ANO OVERFLOW A~) Rou-E TO ;,ROPJSEC STORM DR/IN MANHOL(: -~e;',I ·~o., '--. PROPOSED STPS ~OPS VAL',•!: VAULT At-ID METER VAULT SEE OWG NO. 505 FOR AODITIC»W. INFORMA.TION ROOF ELEV. 429.0' (NOM.) FLOOR ELEV. 418.0' (NOM.) DIMENSIONS 210' x 30' Existing Project Site to bypass: Impervious (Reservoirs & Buildings): o. 17 AC Till Grass (Landscaping): 0.12AC ' ?C'C,.js:L ... -1 ~~ • :=.:.,-: -I 2 ·.~ >, RESl:RVOIR OVERFLO'N~N_G_AN__Q_6!B GAP STRUCTURE Proposed Project Site Basin Ground Cover: Impervious (Reservoir & Road): 0. 76 AC Till Grass (Landscaping): 0.12 AC RDIN ---8'<1ESER',•OR FOOTING OR..1,,IN AND CONt.ECT!0/11 TYP OF 2 I S.::f93:l{ ~ 3-,.,'<.:: :~~ •. '<Pc,\C:CDST'\t, .'.i'.':l -~-.) ,-('t;E·, .. ,REH)f,::,,11,,:;v:·1:-•: PROPOSED ~R~INAGE PLAN=•- 'jl 11·;:,. 1 -, ;' r I, ! / ~- --'-'<u''l'::,:O ;.::,F'>i.:O.l • ~· : T•1 rR[[ DRf'l(JING sr •. ;~ PROPOSED 4:W44S CONCRETE RESERVOIR CAPACITY 6.3MG@445.SOE (HLD445) CAPACITY· 4.7MG@439.8' O.E. (HLD435) SEE OWG NO SOt FOR ADOITIONAl INFORMATIOO OVERFLOW ELEV. 439.8'1445.5' ROOF ELEV 450.0' (NOM.) FLOOR ELEV 425.0' (NOM) D1MENSIONS.174'x259' PROPOSED INLETIOUTLET PIPING, SEE OWG NO t.101 FORAOOmOOALINFORMATION P~.":P,::·si::-. ·s '.'/:SF ~RF~ ~;R:, I 'J~ ~.:.TC" T,p Cf-" '',\:;;_,·,:,, ; ;: ------, !!5 ~ "Ill !ir:Q z ~~!.. '.3 ~:~ 0. ~~~ ~ ~~s:; <( "°'"' z C::;! < ;,., a: i-,~~ 0 i;p::'-l 0 ::s~ m ~~ 0 ~ ~ a: 0. :1 I I I • z ~ (.!) i in ul ! <JJ 0 ~,i ~ ~ cl: u z ; ' a: ~ ;; ~ ii ii ul .. er. '' D-! ~ I . ~ " . ii SCALE SHOWN ~ M411'11;(ll51V4SCAEW>IEh /JJ!i!~S;?" c,ol"fo y,, Predev.pks Flow Frequency Analysis LogPearson III coefficients Time series File:predev.tsf Mean~ -0.628 StdDev= 0.112 Project Location:Sea-Tac skew= 0.411 ---Annual Peak Flow Rates--------Flow Frequency Analysis------- Flow Rate Rank Time of Peak --Peaks --Rank Return Prob (CFS) (CFS) Period 0.251 21 2/16/49 21 00 0.443 1 89.50 0.989 0.415 2 3/03/50 16 00 0.415 2 32.13 0.969 0.264 15 2/09/51 2 00 0.404 3 19. 58 0.949 0.186 44 10/15/5113 00 0.369 4 14.08 0.929 0.184 45 3/24/53 15 00 0.321 5 10.99 0.909 0.226 27 12/19/53 19 00 0. 320 6 9.01 0.889 0.234 22 2/07/55 17 00 0.316 7 7.64 0.869 0.233 24 12/20/55 17 00 0.303 8 6.63 0.849 0.273 13 12/09/56 14 00 0.296 9 5.86 0.829 0.233 25 12/25/57 16 00 0.292 10 5.24 0.809 0.176 47 11/18/58 13 00 0.286 11 4.75 0.789 0.234 23 11/20/59 5 00 0.282 12 4.34 0.769 0.204 35 2/14/61 21 00 0.273 13 3.99 0.749 0.190 41 11/22/61 2 00 0.265 14 3.70 0. 729 0.203 36 12/15/62 2 00 0.264 15 3.44 0.709 0.229 26 12/31/63 23 00 0.264 16 3.22 0.690 0.201 37 12/21/64 4 00 0.261 17 3.03 0.670 0.207 33 1/05/66 16 00 0.261 18 2.85 0.650 0.292 10 11/13/66 19 00 0.260 19 2.70 0.630 0. 320 6 8/24/68 16 00 0.253 20 2.56 0.610 0.193 39 12/03/68 16 00 0.251 21 2.44 0.590 0.207 32 1/13/70 22 00 0.234 22 2. 32 0. 570 0.197 38 12/06/70 8 00 0.234 23 2.22 0.550 0. 316 7 2/27 /72 7 00 0.233 24 2.13 0.530 0.186 43 1/13/73 2 00 0.233 25 2.04 0.510 0.213 29 11/28/73 9 00 0.229 26 1.96 0.490 0.296 9 12/26/74 23 00 0.226 27 1.89 0.470 0.193 40 12/02/75 20 00 0.219 28 1.82 0.450 0.209 31 8/26/77 2 00 0.213 29 1. 75 0.430 0.286 11 9/17/78 2 00 0.212 30 1.70 0.410 0.253 20 9/08/79 15 00 0.209 31 1.64 0.390 0.261 18 12/14/79 21 00 0.207 32 1.59 0.370 0.264 16 11/21/80 11 00 0.207 33 1.54 0.350 0.369 4 10/06/81 15 00 0.204 34 1.49 0.330 0.261 17 10/28/82 16 00 0.204 35 1.45 0.310 0.219 28 1/03/84 1 00 0.203 36 1.41 0.291 0.180 46 6/06/85 22 00 0.201 37 1. 37 0.271 0.282 12 1/18/86 16 00 0.197 38 1. 33 0.251 0.321 5 10/26/86 0 00 0.193 39 1. 30 0.231 0.146 49 11/11/87 0 00 0.193 40 1.27 0.211 0.189 42 8/21/89 17 00 0.190 41 1.24 0.191 0.443 1 1/09/90 6 00 0.189 42 1.21 0.171 0.404 3 11/24/90 8 00 0.186 43 1.18 0.151 0.212 30 1/27/92 15 00 0.186 44 1.15 0.131 0.135 50 11/01/92 16 00 0.184 45 1.12 0.111 0.156 48 11/30/93 22 00 0.180 46 1.10 0.091 0.204 34 11/30/94 4 00 0.176 47 1.08 0.071 0.303 8 2/08/96 10 00 0.156 48 1.05 0.051 0.265 14 1/02/97 6 00 0.146 49 1.03 0.031 0.260 19 10/04/97 15 00 0.135 50 1.01 0.011 computed Peaks 0.462 100.00 0.990 computed Peaks 0.422 50.00 0.980 computed Peaks 0.382 25.00 0.960 computed Peaks 0.330 10.00 0.900 computed Peaks 0.320 8.00 0.875 computed Peaks 0.290 5.00 0.800 Page 1 computed Peaks computed Peaks Predev.pks 0.231 0.193 Page 2 2.00 0.500 1.30 0.231 Flow Frequency Analysis Time Series File:dev.tsf Dev.pks LogPearson III coefficients Mean= -0.380 stdoev= 0.100 Project Location:Sea-Tac skew= 0. 507 ---Annual Peak Flow Rates--------Flow Frequency Analysis------- Flow Rate Rank Time of Peak --Peaks Rank Return Prob (CFS) (CFS) Period 0.421 20 2/16/49 21 00 0.702 1 89. 50 0.989 0.646 4 3/03/50 16 00 0.675 2 32.13 0.969 0.417 22 2/09/51 2 00 0.652 3 19. 58 0.949 0.357 38 10/15/51 13 00 0.646 4 14.08 0.929 0.331 43 3/24/53 15 00 0.615 5 10.99 0.909 0.395 28 12/19/53 19 00 0.604 6 9.01 0.889 0.415 23 11/25/54 2 00 0.551 7 7.64 0.869 0.404 24 11/18/55 15 00 0.545 8 6.63 0.849 0.464 15 12/09/56 14 00 0.508 9 5.86 0.829 0.419 21 12/25/57 16 00 0.497 10 5.24 0.809 0.316 47 11/18/58 13 00 0.492 11 4.75 0.789 0.397 27 11/20/59 5 00 0.492 12 4.34 0.769 0.354 39 2/14/61 21 00 0.487 13 3.99 0.749 0.359 37 11/22/61 2 00 0.484 14 3.70 0.729 0.350 40 12/15/62 2 00 0.464 15 3.44 0.709 0.401 26 12/31/63 23 00 0.459 16 3.22 0.690 0.362 34 12/21/64 4 00 0.456 17 3.03 0.670 0.360 36 1/05/66 16 00 0.443 18 2.85 0.650 0. 545 8 11/13/66 19 00 0.438 19 2.70 0.630 0.604 6 8/24/68 16 00 0.421 20 2.56 0.610 0.327 44 12/03/68 16 00 0.419 21 2.44 0.590 0.362 35 1/13/70 22 00 0.417 22 2. 32 0.570 0.349 41 12/05/70 9 00 0.415 23 2.22 0.550 0. 508 9 12/08/71 18 00 0.404 24 2.13 0.530 0. 323 46 1/13/73 2 00 0.401 25 2.04 0.510 0.377 31 11/28/73 9 00 0.401 26 1.96 0.490 0.487 13 12/26/74 23 00 0.397 27 1.89 0.470 0.324 45 12/02/75 20 00 0.395 28 1.82 0.450 0.401 25 8/26/77 2 00 0.382 29 1. 75 0.430 0. 551 7 9/17/78 2 00 0.381 30 1. 70 0.410 0.492 12 9/08/79 15 00 0.377 31 1.64 0.390 0.456 17 12/14/79 21 00 0.375 32 1. 59 0.370 0.492 11 11/21/80 11 00 0.370 33 1. 54 0.350 0.675 2 10/06/81 0 00 0.362 34 1.49 0.330 0.497 10 10/28/82 16 00 0.362 35 1.45 0.310 0.382 29 1/03/84 1 00 0.360 36 1.41 0.291 0.343 42 6/06/85 22 00 0.359 37 1. 37 0.271 0.443 18 1/18/86 16 00 0.357 38 1. 33 0.251 0.615 5 10/26/86 0 00 0.354 39 1. 30 0.231 0.286 49 11/11/87 0 00 0.350 40 1.27 0.211 0.370 33 8/21/89 17 00 0.349 41 1.24 0.191 0.702 1 1/09/90 6 00 o. 343 42 1.21 0.171 0.652 3 11/24/90 8 00 0.331 43 1.18 0.151 0.375 32 1/27/92 15 00 0. 327 44 1.15 0.131 0.263 50 11/01/92 16 00 0.324 45 1.12 0.111 0.301 48 11/30/93 22 00 0.323 46 1.10 0.091 0.381 30 11/30/94 4 00 0.316 47 1.08 0.071 0.459 16 2/08/96 10 00 0.301 48 1.05 0.051 0.438 19 1/02/97 6 00 0.286 49 1.03 0.031 0.484 14 10/04/97 15 00 0.263 50 1.01 0.011 computed Peaks 0.776 100.00 0.990 computed Peaks 0.712 50.00 0.980 computed Peaks 0.649 25.00 0.960 computed Peaks 0. 566 10.00 0.900 computed Peaks o. 550 8.00 0.875 computed Peaks o. 503 5.00 0.800 Page 1 computed Peaks computed Peaks Dev.pks 0.409 0.349 Page 2 2.00 0.500 1.30 0.231 Bypass.pks Flow Frequency Analysis LogPearson III coefficients Time series File:bypass.tsf Mean= -1.917 StdDev= 0.163 Project Location:sea-Tac Skew= 0.451 ---Annual Peak Flow Rates--------Flow Frequency Analysis------- Flow Rate Rank Time of Peak --Peaks Rank Return Prob (CFS) (CFS) Period 0.013 19 2/16/49 21 00 0.031 1 89.50 0.989 0.031 1 3/03/50 16 00 0.030 2 32 .13 0.969 0.016 9 2/09/51 2 00 0.026 3 19.58 0.949 0.009 37 1/30/52 8 00 0.023 4 14.08 0.929 0.008 43 3/24/53 15 00 0.020 5 10.99 0.909 0.012 26 12/19/53 19 00 0.019 6 9.01 0.889 0.013 21 2/07/55 17 00 0.018 7 7.64 0.869 0.013 20 12/20/55 17 00 0.016 8 6.63 0.849 0.015 11 12/09/56 14 00 0.016 9 5.86 0.829 0.012 24 12/25/57 16 00 0.016 10 5.24 0.809 0.009 41 1/26/59 20 00 0.015 11 4.75 0.789 0.012 22 11/20/59 20 00 0.015 12 4.34 0.769 0.011 30 2/14/61 21 00 0.015 13 3.99 0.749 0.009 40 11/22/61 2 00 0.015 14 3.70 0.729 0.011 28 12/15/62 2 00 0.015 15 3.44 0.709 0.011 29 12/31/63 23 00 0.015 16 3.22 0.690 0.009 38 12/21/64 4 00 0.014 17 3.03 0.670 0.010 34 1/05/66 16 00 0.014 18 2.85 0.650 0.016 10 11/13/66 19 00 0.013 19 2.70 0.630 0.015 12 8/24/68 16 00 0.013 20 2.56 0.610 0.010 36 12/03/68 16 00 0.013 21 2.44 o. 590 0.011 32 1/13/70 22 00 0.012 22 2.32 0. 570 0.011 33 12/06/70 8 00 0.012 23 2.22 0. 550 0.020 5 2/27 /72 7 00 0.012 24 2 .13 o. 530 0.009 42 1/13/73 2 00 0.012 25 2.04 0.510 0.012 23 11/28/73 9 00 0.012 26 1.96 0.490 0.018 7 12/26/74 23 00 0.012 27 1.89 0.470 0.010 35 12/02/75 20 00 0.011 28 1.82 0.450 0.008 45 8/26/77 2 00 0.011 29 1. 75 0.430 0.014 17 9/22/78 19 00 0.011 30 1. 70 0.410 0.008 44 9/08/79 15 00 0.011 31 1.64 0.390 0.015 13 12/14/79 21 00 0.011 32 1. 59 0.370 0.014 18 11/21/80 11 00 0.011 33 1. 54 0.350 0.023 4 10/06/8115 00 0.010 34 1.49 0.330 0.012 27 10/28/82 16 00 0.010 35 1.45 0.310 0.012 25 3/15/84 20 00 0.010 36 1.41 0.291 0.008 46 6/06/85 22 00 0.009 37 1. 37 0.271 0.016 8 1/18/86 16 00 0.009 38 1. 33 0.251 0.015 15 11/24/86 3 00 0.009 39 1. 30 0.231 0.007 48 1/14/88 12 00 0.009 40 1.27 0.211 0.007 47 11/05/88 14 00 0.009 41 1.24 0.191 0.030 2 1/09/90 6 00 0.009 42 1.21 0.171 0.026 3 11/24/90 8 00 0.008 43 1.18 0.151 0.011 31 1/27/92 15 00 0.008 44 1.15 0.131 0.006 49 3/22/93 22 00 0.008 45 1.12 0.111 0.005 50 11/30/93 22 00 0.008 46 1.10 0.091 0.009 39 11/30/94 4 00 0.007 47 1.08 0.071 0.019 6 2/08/96 10 00 0.007 48 1.05 0.051 0.015 14 1/02/97 6 00 0.006 49 1.03 0.031 0.015 16 10/04/97 15 00 0.005 50 1.01 0.011 computed Peaks 0.033 100.00 0.990 Computed Peaks 0.029 50.00 0.980 computed Peaks 0.025 25.00 0.960 computed Peaks 0.020 10.00 0.900 computed Peaks 0.019 8.00 0.875 computed Peaks 0.016 5.00 0.800 Page 1 computed Peaks computed Peaks Bypass.pks 0.012 0.009 Page 2 2.00 0.500 1.30 0.231 Honey Creek -Retention/Detention Facility Type of Facility: Facility Length: Facility Width: Facility Area: Effective Storage Depth: Stage O Elevation: Storage Volume: Riser Head: Riser Diameter: Number of orifices: Detention Vault 40.00 ft 30.00 ft 1200. sq. 8.00 ft 418.00 ft 9600. cu. 8.00 ft ft ft 18.00 inches 2 Full Head Pipe Orifice # Height (ft) 0.00 6.00 Diameter Discharge Diameter 1 2 Top Notch Weir: Outflow Rating Curve: (in) 1. 50 2.20 None None (CFS) (in) 0.173 0.186 6.0 Stage Elevation Storage Discharge (ft) (ft) (cu. ft) (ac-ft) (cfs) 0.00 418.00 0. 0.000 0.000 0.02 418.02 24. 0.001 0.008 0.03 418.03 36. 0.001 0. 011 0.05 418.05 60. 0.001 0.013 0.06 418.06 72. 0.002 0.015 0.08 418.08 96. 0.002 0.017 0.09 418.09 108. 0.002 0.019 0 .11 418.11 132. 0.003 0.020 0.13 418.13 156. 0.004 0.022 0.26 418.26 312. 0.007 0.031 0.40 418.40 480. 0. 011 0.038 0.53 418.53 636. 0.015 0.045 0. 67 418.67 804. 0.018 0.050 0.80 418.80 960. 0.022 0.055 0.94 418.94 1128. 0.026 0.059 1. 07 419.07 1284. 0.029 0.063 1. 21 419.21 1452. 0.033 0.067 1.35 419.35 1620. 0.037 0.071 1. 48 419.48 1776. 0.041 0.074 1. 62 419.62 1944. 0.045 0.078 1. 75 419.75 2100. 0.048 0.081 1. 89 419.89 2268. 0.052 0.084 2.02 420.02 2424. 0.056 0.087 2.16 420.16 2592. 0.060 0.090 2.29 420.29 2748. 0.063 0.092 2.43 420.43 2916. 0.067 0.095 2.57 420.57 3084. 0.071 0.098 2.70 420.70 3240. 0.074 0.100 2.84 420.84 3408. 0.078 0.103 Percolation (cfs) 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 2.97 420.97 3564. 0.082 0.105 0.00 3.11 421.11 3732. 0.086 0.108 0.00 3.24 421.24 3888. 0.089 0.110 0.00 3.38 421. 38 4056. 0.093 0 .112 0.00 3.51 421.51 4212. 0.097 0 .114 0.00 3.65 421. 65 4380. 0.101 0.117 0.00 3.79 421.79 4548. 0.104 0 .119 0.00 3.92 421. 92 4704. 0.108 0.121 0.00 4.06 422.06 4872. 0.112 0.123 0.00 4.19 422.19 5028. 0 .115 0.125 0.00 4.33 422.33 5196. 0 .119 0.127 0.00 4.46 422.46 5352. 0.123 0.129 0.00 4.60 422.60 5520. 0.127 0.131 0.00 4.74 422.74 5688. 0.131 0.133 0.00 4.87 422.87 5844. 0.134 0.135 0.00 5.01 423.01 6012. 0.138 0.137 0.00 5.14 423.14 6168. 0.142 0.138 0.00 5.28 423.28 6336. 0.145 0.140 0.00 5.41 423.41 6492. 0.149 0.142 0.00 5.55 423.55 6660. 0.153 0.144 0.00 5.68 423.68 6816. 0.156 0.146 0.00 5.82 423.82 6984. 0.160 0.147 0.00 5.96 423.96 7152. 0.164 0.149 0.00 6.00 424.00 7200. 0.165 0 .149 0.00 6.02 424.02 7224. 0.166 0.151 0.00 6.05 424.05 7260. 0.167 0.155 0.00 6.07 424.07 7284. 0.167 0.161 0.00 6.09 424.09 7308. 0.168 0.170 0.00 6 .11 424.11 7332. 0.168 0.181 0.00 6.14 424.14 7368. 0.169 0.194 0.00 6.16 424.16 7392. 0.170 0.204 0.00 6.18 424.18 7416. 0.170 0.208 0.00 6.32 424.32 7584. 0.174 0.228 0.00 6.45 424.45 7740. 0.178 0.244 0.00 6.59 424.59 7908. 0.182 0.258 0.00 6.73 424.73 8076. 0.185 0.270 0.00 6.86 424.86 8232. 0.189 0.282 0.00 7.00 425.00 8400. 0.193 0.293 0.00 7 .13 425.13 8556. 0.196 0.303 0.00 7.27 425.27 8724. 0.200 0.312 0.00 7.40 425.40 8880. 0.204 0.322 0.00 7.54 425.54 9048. 0.208 0.330 0.00 7.67 425. 6 7 9204. 0. 211 0.339 0.00 7.81 425.81 9372. 0.215 0.347 0.00 7.95 425.95 9540. 0.219 0.355 0.00 8.00 426.00 9600. 0.220 0.358 0.00 8.10 426.10 9720. 0.223 0.826 0.00 8.20 426.20 9840. 0.226 1.680 0.00 8.30 426.30 9960. 0.229 2.780 0.00 8.40 426.40 10080. 0.231 4.080 0.00 8.50 426.50 10200. 0.234 5.550 0.00 8.60 426.60 10320. 0.237 6.980 0.00 8.70 426.70 10440. 0.240 7.520 0.00 8.80 426.80 10560. 0.242 8.010 0.00 8.90 426.90 10680. 0.245 8.480 0.00 9.00 427.00 10800. 0.248 8.920 0.00 9.10 427.10 10920. 0.251 9.340 0.00 9.20 427.20 11040. 0.253 9.740 0.00 9.30 427.30 11160. 0.256 10.130 0.00 9.40 427.40 11280. 0.259 10.500 0.00 9.50 427.50 11400. 0.262 10.860 0.00 9.60 427. 60 11520. 0.264 11. 200 0.00 9.70 427.70 11640. 0.267 11. 540 0.00 9.80 427.80 11 760. 0.270 11. 860 0.00 9.90 427.90 11880. 0.273 12.180 0.00 Hyd Inflow outflow Peak Storage Stage Elev (Cu-Ft) (Ac-Ft) 1 0.70 0.38 8.00 426.00 2 0.65 0.34 7.71 425. 71 3 0.67 0.34 7.61 425.61 4 0.46 0.28 6.82 424.82 5 0.38 0.22 6.30 424.30 6 0.49 0.21 6.18 424.18 7 0.31 0.12 3.98 421.98 8 0.30 0.12 3.74 421.74 Hyd R/D Facility Tributary Reservoir Outflow Inflow Inflow 1 0.38 0.03 ******** 2 0.34 0.03 ******** 3 0.34 0.02 ******** 4 0.28 0.02 ******** 5 0.22 0.01 ******** 6 0.21 0.02 ******** 7 0.12 0.01 ******** 8 0.12 0.01 ******** Route Time Series through Facility Inflow Time Series File:dev.tsf Outflow Time Series File:rdout POC Time Series File:dsout Inflow/Outflow Analysis Peak Inflow Discharge: 0.702 CFS Peak Outflow Discharge: 0.379 CFS Peak Reservoir Stage: 8.00 Ft Peak Reservoir Elev: 426.00 Ft 9605. 0.221 9257. 0.213 9136. 0.210 8186. 0.188 7557. 0.173 7416. 0.170 4778. 0.110 4489. 0.103 POC Outflow Target Cale 0.46 0.39 ******* 0.35 ******* 0.34 ******* 0.29 ******* 0.23 ******* 0.22 ******* 0 .13 ******* 0.12 at 6:00 on Jan 9 in at 10:00 on Jan 9 in Peak Reservoir Storage: 9605. Cu-Ft 0.221 Ac-Ft Add Time Series:bypass.tsf Peak Summed Discharge: 0.388 CFS at 10:00 on Jan 9 in Point of Compliance File:dsout.tsf Flow Duration from Time Series File:rdout.tsf Cutoff Count Frequency CDF Exceedence_Probability 1990 1990 1990 CFS % % % 0.005 363025 82.882 82.882 1 7 .118 0 .1 71E+OO 0.016 20450 4.669 87.551 12.449 0.124E+OO 0.027 16321 3.726 91.278 8. 722 0.872E-Ol 0.037 12196 2.784 94.062 5.938 0.594E-01 0.048 8426 1. 924 95.986 4.014 0.401E-01 0.059 6569 1.500 97.486 2.514 0.251E-01 0.069 4278 0.977 98.462 1.538 0.154E-Ol 0.080 2524 0.576 99.039 0.961 0. 96 lE-02 0.090 1699 0.388 99.426 0.574 0.574E-02 0.101 983 0.224 99.651 0.349 0.349E-02 0 .112 605 0.138 99.789 0 .211 0.211E-02 0.122 390 0.089 99.878 0.122 0.122E-02 0.133 233 0.053 99.931 0.069 0.687E-03 0.144 125 0.029 99.960 0.040 0.402E-03 0.154 67 0.015 99.975 0.025 0.249E-03 0.165 8 0.002 99.977 0.023 0.231E-03 0.176 6 0.001 99.978 0.022 0.217E-03 0.186 4 0.001 99.979 0.021 0.208E-03 0.197 6 0.001 99.981 0.019 0.194E-03 0.207 7 0.002 99.982 0.018 0.178E-03 0.218 12 0.003 99.985 0.015 0.151E-03 0.229 6 0.001 99.986 0.014 0 .137E-03 0.239 9 0.002 99.988 0.012 0 .116E-03 0.250 9 0.002 99.990 0.010 0.959E-04 0.261 7 0.002 99.992 0.008 0.799E-04 0.271 12 0.003 99.995 0.005 0.525E-04 0.282 8 0.002 99.997 0.003 0.342E-04 0.293 1 0.000 99.997 0.003 0.320E-04 0.303 3 0.001 99.997 0.003 0.251E-04 0.314 4 0.001 99.998 0.002 0.160E-04 0.324 1 0.000 99.999 0.001 0 .137E-04 0.335 1 0.000 99.999 0.001 0 .114E-04 0.346 4 0.001 100.000 0.000 0.228E-05 0.356 0 0.000 100.000 0.000 0.228E-05 0.367 0 0.000 100.000 0.000 0.228E-05 0.378 0 0.000 100.000 0.000 0.228E-05 Flow Duration from Time Series File:dsout.tsf Cutoff Count Frequency CDF Exceedence_Probability CFS % % % 0.006 361824 82.608 82.608 17.392 0.174E+OO 0.016 21444 4 .896 87.504 12. 496 0.125E+OO 0.027 16326 3. 727 91.232 8.768 0.877E-01 0.038 12276 2.803 94.034 5.966 0.597E-Ol 0.049 8320 1.900 95.934 4.066 0.407E-01 0.060 6541 1.493 97.427 2.573 0.257E-01 0.071 4365 0.997 98.424 1.576 0.158E-01 0.082 2514 0.574 98.998 1.002 O.lOOE-01 0.093 1742 0.398 99.395 0.605 0.605E-02 0.104 1018 0.232 99.628 0 .372 0. 372E-02 0 .114 605 0 .138 99.766 0.234 0.234E-02 0.125 409 0.093 99.859 0.141 0.141E-02 0.136 287 0.066 99. 925 0.075 0.751E-03 0.147 0.158 0.169 0.180 0.191 0.202 0. 213 0.223 0.234 0.245 0.256 0.267 0.278 0.289 0.300 0. 311 0.321 0.332 0.343 0.354 0.365 0.376 0.387 118 92 15 9 2 7 5 9 10 9 7 9 9 9 2 5 5 0 3 2 1 0 0 0.027 0.021 0.003 0.002 0.000 0.002 0.001 0.002 0.002 0.002 0.002 0.002 0.002 0.002 0.000 0.001 0.001 0.000 0.001 0.000 0.000 0.000 0.000 99.952 99.973 99.976 99.978 99.979 99.980 99.982 99.984 99.986 99.988 99.989 99.992 99.994 99.996 99. 996 99.997 99.998 99.998 99.999 100.000 100.000 100.000 100.000 Duration Comparison Anaylsis Base File: predev.tsf New File: dsout.tsf Cutoff Units: Discharge in CFS Cutoff 0 .115 0.140 0.165 0.191 0.216 0.241 0.266 0.291 0.317 0.342 0.367 0.392 0.418 0.443 -----Fraction of Time----- Base New %Change 0.26E-02 0.23E-02 -11.0 0.13E-02 0.66E-03 -49.1 0.72E-03 0.25E-03 -65.5 0.42E-03 0.21E-03 -49.2 0.24E-03 0.17E-03 -26.2 0.12E-03 0.13E-03 5.6 0.68E-04 0.84E-04 23.3 0.48E-04 0.39E-04 -19.0 0.25E-04 0.23E-04 -9.1 0.18E-04 O.llE-04 -37.5 0.16E-04 0.23E-05 -85.7 0.91E-05 O.OOE+OO -100.0 0.23E-05 O.OOE+OO -100.0 0.23E-05 0.00E+OO -100.0 0.048 0.027 0.024 0.022 0.021 0.020 0.018 0.016 0.014 0.012 0 .011 0.008 0.006 0.004 0.004 0.003 0.002 0.002 0.001 0.000 0.000 0.000 0.000 0.482E-03 0. 272E-03 0.237E-03 0.217E-03 0.212E-03 0 .196E-03 0.185E-03 0.164E-03 0.142E-03 0.121E-03 0.105E-03 0.845E-04 0.639E-04 0.434E-04 0.388E-04 0.274E-04 0.160E-04 0.160E-04 0. 913E-05 0.457E-05 0.228E-05 0.228E-05 0.228E-05 ---------Check of Tolerance------- Probability Base New %Change 0.26E-02 0.115 0.113 -2.0 0.13E-02 0.140 0.126 -9.8 0.72E-03 0.165 0.138 -16.8 0.42E-03 0.191 0.150 -21.2 0.24E-03 0.216 0.170 -21.2 0.12E-03 0.241 0.243 1.0 0.68E-04 0.266 0.275 3.3 0.48E-04 0.291 0.286 -1.9 0.25E-04 0.317 0.314 -0.7 0.18E-04 0.342 0.321 -6.2 0.16E-04 0.367 0.332 -9.4 0.91E-05 0.392 0.343 -12.4 0.23E-05 0.418 0.388 -7.2 0.23E-05 0.443 0.388 -12.5 Maximum positive excursion= 0.009 cfs 3.6%) occurring at 0.265 cfs on the Base Data:predev.tsf and at 0.275 cfs on the New Data:dsout.tsf Maximum negative excursion= 0.051 cfs (-24.4%) occurring at 0.210 cfs on the Base Data:predev.tsf and at 0.158 cfs on the New Data:dsout.tsf Route Time Series through Facility Inflow Time Ser es File:dev.tsf Outflow Time Ser es File:rdout POC Time Ser es File:dsout Inflow/Outflow Analysis Peak Inflow Discharge: 0.702 CFS at 6:00 on Jan 9 in 1990 Peak Outflow Discharge: 0.379 CFS at 10:00 on Jan 9 in 1990 Peak Reservoir Stage: 8.00 Ft Peak Reservoir Elev: 426.00 Ft Peak Reservoir Storage: 9605. Cu-Ft 0.221 Ac-Ft Add Time Series:bypass.tsf Peak Summed Discharge: 0.388 CFS at 10:00 on Jan 9 in 1990 Point of Compliance File:dsout.tsf Flow Duration from Time Series File:rdout.tsf Cutoff Count Frequency CDF Exceedence_Probability CFS % % % 0.005 363025 82.882 82.882 1 7 .118 0.171E+OO 0.016 20450 4.669 87.551 12.449 0.124E+OO 0.027 16321 3. 726 91. 278 8. 722 0.872E-01 0.037 12196 2.784 94.062 5.938 0.594E-01 0.048 8426 1. 924 95.986 4.014 0.401E-01 0.059 6569 1. 500 97.486 2.514 0.251E-01 0.069 4278 0.977 98.462 1.538 0.154E-01 0.080 2524 0.576 99.039 0.961 0.961E-02 0.090 1699 0.388 99.426 0.574 0.574E-02 0.101 983 0.224 99.651 0.349 0.349E-02 0 .112 605 0.138 99.789 0 .211 0. 211E-02 0.122 390 0.089 99.878 0.122 0.122E-02 0.133 233 0.053 99.931 0.069 0.687E-03 0.144 125 0.029 99. 960 0.040 0.402E-03 0.154 67 0.015 99.975 0.025 0.249E-03 0.165 8 0.002 99.977 0.023 0.231E-03 0.176 6 0.001 99.978 0.022 0.217E-03 0.186 4 0.001 99.979 0.021 0.208E-03 0.197 6 0.001 99.981 0.019 0.194E-03 0.207 7 0.002 99.982 0.018 0.178E-03 0.218 12 0.003 99.985 0.015 0.151E-03 0.229 6 0.001 99.986 0.014 0.137E-03 0.239 9 0.002 99.988 0.012 0 .116E-03 0.250 9 0.002 99.990 0.010 0.959E-04 0.261 7 0.002 99. 992 0.008 0.799E-04 0 .271 12 0.003 99.995 0.005 0.525E-04 0.282 8 0.002 99.997 0.003 0.342E-04 0.293 1 0.000 99.997 0.003 0.320E-04 0.303 3 0.001 99.997 0.003 0.251E-04 0.314 4 0.001 99.998 0.002 0.160E-04 0.324 1 0.000 99.999 0.001 0.137E-04 0.335 1 0.000 99.999 0.001 0 .114E-04 0.346 4 0.001 100.000 0.000 0.228E-05 0.356 0 0.000 100.000 0.000 0.228E-05 0.367 0 0.000 100.000 0.000 0.228E-05 0.378 0 0.000 100.000 0.000 0.228E-05 Flow Duration from Time Series File:dsout.tsf Cutoff Count Frequency CDF Exceedence_Probability CFS % % % 0.006 361824 82.608 82.608 17. 392 0.174E+OO 0.016 21444 4. 896 87.504 12. 496 0.125E+OO 0.027 16326 3. 727 91.232 8.768 0.877E-01 0.038 12276 2.803 94.034 5.966 0.597E-01 0.049 8320 1. 900 95.934 4.066 0.407E-Ol 0.060 6541 1. 493 97.427 2. 573 0.257E-01 0 .071 4365 0.997 98.424 1. 576 0.158E-01 0.082 2514 0.574 98.998 1.002 O.lOOE-01 0.093 1742 0.398 99.395 0.605 0.605E-02 0.104 1018 0.232 99.628 0.372 0. 372E-02 0 .114 605 0.138 99.766 0.234 0.234E-02 0.125 409 0.093 99.859 0.141 0 .141E-02 0.136 287 0.066 99.925 0.075 0.751E-03 0.147 118 0.027 99.952 0.048 0.482E-03 0.158 92 0.021 99.973 0. 027 0.272E-03 0.169 15 0.003 99.976 0.024 0.237E-03 0.180 9 0.002 99.978 0.022 0.217E-03 0.191 2 0.000 99.979 0.021 0.212E-03 0.202 7 0.002 99.980 0.020 0 .196E-03 0.213 5 0.001 99.982 0.018 0.185E-03 0.223 9 0.002 99.984 0.016 0.164E-03 0.234 10 0.002 99.986 0.014 0.142E-03 0.245 9 0.002 99.988 0.012 0.121E-03 0.256 7 0.002 99.989 0. 011 0.105E-03 0.267 9 0.002 99.992 0.008 0.845E-04 0.278 9 0.002 99.994 0.006 0.639E-04 0.289 9 0.002 99.996 0.004 0.434E-04 0.300 2 0.000 99.996 0.004 0.388E-04 0 .311 5 0.001 99.997 0.003 0.274E-04 0.321 5 0.001 99.998 0.002 0.160E-04 0.332 0 0.000 99.998 0.002 0.160E-04 0.343 3 0.001 99.999 0.001 0.913E-05 0.354 2 0.000 100.000 0.000 0.457E-05 0.365 1 0.000 100.000 0.000 0.228E-05 0.376 0 0.000 100.000 0.000 0.228E-05 0.387 0 0.000 100.000 0.000 0.228E-05 Honey Creek Flow Control Duration Standard -Matching Forested Site Conditions -KCRTS Modeling "' 0 I rdout.dur 0 dsout dur • Targetdur 0 J ~ ci R 'iii <') u. ci ~ Q) ~ <'Cl .c <.) i5 N ci ct 0 0 ci f-:o 10 -s ,--,n,, r, r, n1 1T, ---,---1 I I I I I 11 I -,,,mrrr--,-~--1 I 1111 I I I 1111 I I I I I I iii x I I I I I 1111 10 -5 10 -4 10 -3 10 -1 10° Probability Exceedence APPENDIX/ CONVEYANCE SYSTEMS BACKWATER ANALYSIS EXISTING AND PROPOSED CONVEYANCE SYSTEMS BACKWATER ANALYSES -HIGHLANDS 435 ZONE RESERVIORS STORMWATER FACILITIES (TO BE PROVIDED AT UTILITY CONSTRUCTION PERMIT SUBMITTAL) APPENDIXJ O&MMANUAL OPERATIONS AND MAINTENANCE MANUAL FOR HIGHLANDS 435 ZONE RESERVIORS STORMWATER FACILITIES (TO BE PROVIDED AT UTILITY CONSTRUCTION PERMIT SUBMITTAL)