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HomeMy WebLinkAboutMisc1WIT4 Cirk F71 I Firestone 421 Union Avenue NE Renton, Washingfon Surface Wafer Drainage Technical information Report Re 1I. -lo I Won D REV14SED Firestone 421 Union Avenue NE Renton, Washington Surface Water Drainage Technical Information Report �f L2 3437 February 14, 2011 ■� rmr Y 1505 Westlake Ave. N T 206.522.9510 Suite 305 F 206.522.8344 Seattle, WA 98109 www.pacland.com Jeff Chambers, P.E. Max Berde Firestone Technical Information Report Renton, Washington ProjectOverview ................................................................................................................... 4 1. Site Location ............................................................................................................... 4 2, Drainage Basins, Site Characteristics, and Sub -basins ................................................... 5 3. Soils ............................................................. .............................................................. S 4' Infiltration ............................................................................................................ ........ 6 OffsiteAnalysis ................... ...................... ................................................... ..................... 1O l. Upstream Analysis ..................................................................................................... lO 2. Downstream Analysis ........................... .................................................................... 1O 3. Evidence ofExisting nrPredicted Problems ................................................................ 1U Retention/Detention Analysis and Design ....................................................... .................... 1l 1. Hydrologic Analysis .................................................................................................. 1 2. Matching Forested Site Conditions ............................................................................. 12 3. Offsite Flows ..... ....................................................................... ................... ........... 13 4. Water Quality ..... ................................................ ................................. ................. 13 Conveyance System Analysis and Design ....... ..................................................................... l5 SpecialReports and Studies ................................................................................................. 78 OtherPermits ............................................................... ...................................................... O Bond Quantities, Facility Summaries, and Declaration of Covenant....... ...... __ .................... 19 Appendices: A—Draimage Basin Exhibits B—Flow Control Application Map C— Forested and Proposed Runoff Calculations D— Detention Calculations E —Wmter Quality Calculations F—Unfiltratimn Feasibility Study r r r L r 1 1 Firestone Technical Information Report Renton, Washington Site Location: The property is located at 421 Union Avenue NE in Renton, Washington. The site is bordered by NE 4`" Place to the north, Union Ave NE to the east, residential and restaurant uses to the west, and a restaurant to the south. The site is currently vacant and was previous developed as a restaurant. This project proposes to construct a 7,654 square foot Firestone auto care building on the 1.22 acre site. Design Criteria: The City of Renton uses the City of Renton Amendments to the King County Surface Water Management Design Manual (KCSWDM), 2009 Edition. Because the project proposes to add and replace more than 2000 sf of impervious surfaces, detention is required. This project will evaluate the pre -developed and post -developed site conditions, matching the stormwater runoff durations from one-half the 2 -year through the 50 -year storm events. The pre -developed condition will be modeled as 100% forested based on the City of Renton Flow Control Duration Standard Matching Forested Conditions, as shown in the Flow Control Application Map in Appendix B. Additionally, water duality treatment will be provided for the new pollution generating impervious surfaces WGIS). Table 1 Jurisdictional Requirements Peak Runoff Control: Flow Control Duration Standard Matching Forested Site Conditions '/2 2 -year: Match forested condition 2 -year: Match forested condition 10 -year: Match forested condition 50 -year: Match forested condition Water Quality: Enhanced Basic WQ Treatment Preceding detention: 35% of developed 2 -year flow rate Downstream of detention: Full 2 -year release rate from detention Proposed Drainage System: The project proposes to collect and convey onsite runoff with a concrete swale and gutter system to drain the parking areas. The site grading has been designed to allow runoff from the parking lot to sheet flow to the concrete Swale and then flow via concrete gutter and scuppers along the west side of the parking area to the north. Runoff first is treated in a 3,415 CF water duality wetpond and then flows into a StormFilter manhole with CSF media cartridges to provide Enhanced Basic water quality treatment. The treated runoff from the parking areas, as well as the roof runoff, is detained in a 17,314 CF detention pond on the northern portion of the site. A flow control structure out of the detention pond IPAUAND Project # 10.1 13.001 Page 2 71 LI fl i r r 11 1 Firestone Technical Information Report Renton, Washington with two orifices will match the forest - ed pre developed stormwater durations described in the Design Criteria. Runoff will discharge from the onsite flow control structure to the City of Renton stormwater system via a 12" storm drain line running northwest across NE 4`h Place to a storm drain manhole along the northern curb of NE 4"' Place. Conclusion: The proposed stormwater management system for this project has been designed in accordance with regulatory criteria described above and consistent with sound engineering practice. This design has incorporated stormwater detention to meet the Flow Control Duration Standard Matching Forested Site Conditions and stormwater quality BMP's to meet the Enhanced Basic water quality treatment requirements of King County and the City of Renton. Therefore, no significant adverse impacts to the stormwater management system are expected as a result of the proposed development. PAUAND Project # 10.1 13.001 Page 3 Firestone Technical Information Report Renton, Washington Site Location 019 Y"tr NE 3 mr, Vrkp S i I'CPr; i Ike { NE 57th 9 m NC :1b S: NE 11th$t !-uy t g vin: �i NE -Om Pi g 3 n m NE Sdh� gg �'Ez i NE 1(ShAWE 4 LL _ a .. .fin ci ®✓hrmf - b i NE%fi Sl ' 1Mt9~d Fcn c, SkPLB« 6E!—tK y i •X Ah r !�'�,,. NL r... n Cn NE 9th Pt { :IE B1h S1 _ m ,1 C T i s HE Nh 5, NEW L ` es.84 Em At g5 NES„ NE �° 71nN A N s'n NL etr. [t ^ 6653, NE 9N to ->+nA J NE FANW v i,F rfi � •t n NE xn di k NF 4h R E t �P g {F HE e1 P1 1: oir gg a n 44m 6! 'gho- •'•n''r FIE 4h9 HE As, sl NE AC,&, NE AM SI )i NE do, a, rr n R 9' A WI b R Rl:yd v-��ni�' Gre.rF.oee i Ceme1F`Y Nf 'M Ct y pY i Ir 2M Ci o NX n' rJ ]nc HE lid rA 4�:-c Sl h�2r.e s: $ kf =Te s� 2e 8t y, p.� The S N ui 469 Af, .istq { 4 rn Oh'. 1r,A 6E 8E Location: 421 Union Avenue NE, Renton, WA 98056 Section/Township/Range: SE '!a of Section 9, Township 23N, Range 5E of W.M. Parcel/Tax Lot(s): 0923059050 Size: 1.22 acres City, County, State: Renton, King County, Washington Governing Agency: City of Renton Design Criteria: City of Renton Amendments to the 2009 King County Surface Water Design Manual (KCSWDM) PACLAND Project # 10.113.001 Page 4 F1 L 1 ri u 1 Ll Firestone Technical Information Report Renton, Washington Drainage Basins, Subbasins, and Site Characteristics Drainage Basin The project site is located in the Lower Cedar River Basin. Existing Sub -Basins The project site has one existing sub -basin. See Exhibit A in Appendix A for a depiction of the existing sub -basin. Runoff flows across the existing site generally from west to east. Runoff is collected in three catch basins along the south and east property lines and conveyed to the southeast corner of the site by 18" storm pipe. The stormwater is discharged from the site by an 8" storm pipe to the southeast and subsequently into the City of Renton storm system on Union Ave NE. This sub -basin is 1.22 acres. Proposed Sub -Basins The project site has one proposed sub -basin. See Exhibit B in Appendix A for a depiction of the proposed sub -basin. The project proposes to collect onsite runoff with a concrete swale within the southern portion of the parking lot and concrete gutter with scuppers along the western curb and convey stormwater to the north of the site before being discharged into the City of Renton stormwater system on the north side of NE 4"' Place adjacent to the project site. Table 1, below, shows the area breakdown for the existing and proposed sub -basins. Table 1 — Sub -basin Areas Surface Existing Basin (A Proposed Basin (sO Roof (Bldg)* 3,073 7,654 Pavement 33,126 26,974 Landscape 1 16,841 1 18,372 Total 53,000 53,000 -exiting root area assumea rrom existing bturrfmg paa area As shown in Table 1, the amount of impervious surfaces decreases by 1571 SE from the existing use to the proposed condition. Because the existing impervious surfaces are proposed to be replaced, stormwater mitigation is required. Site Characteristics The property is located at 421 Union Avenue NE in Renton, Washington. The site is bordered by NE 4"' Place to the north, Union Ave NE to the east, residential and restaurant uses to the west, and a restaurant to the south. The site is currently vacant and was previous developed as a restaurant. This project proposes to construct a 7,654 square foot Firestone auto care building on the 1.22 acre site. Soils The site is mapped as Alderwood (AgQ Gravelly Sandy Loam according to the USDA Natural Resource Conservation Service, Soil Survey for King County Area, Washington. PACLANQ Project # 10.113.001 Page 5 I Firestone Technical Information Report Renton, Washington The till soil group was used for KCRTS runoff calculations. A complete geotechnical report has not completed for the site. Infiltration An Infiltration Feasibility Study was prepared by Otto Rosenau & Associates, Inc., dated January 17, 2011, to determine the potential for stormwater infiltration onsite. Based on four percolation test pits on the northern portion of the site, the measured infiltration rate was determined to be 0.25 inches/hour. After safety factors, the design infiltration tate would be as low as 0.015 inches/hour. Based on these results, infiltration has been determined to be unfeasible due to the very large size of infiltration pond that would be required. The complete Infiltration Feasibility Study is included in Appendix F. 1 1 1 1 1 �I IPAUAND Project # 10.1 13.001 Page 6 I Firestone Technical Information Report Renton, Washington As required it ed by the 2009 King County Surface Water Design Manual (KCSWDM) and City of Renton Amendments, this project is subject to full drainage review_ Therefore, the storm drainage design for this project is required to comply with all eight (8) Core Requirements and five (5) special requirements. The requirements have been met as follows: Core Requirement #1: Discharge at Natural Location The discharge from a proposed project must occur at the natural location. Response: Onsite runoff will be collected, conveyed, treated, and detained. All onsite runoff is subsequently conveyed to the City of Renton stormwater system which discharges into Maplewood Creek and subsequently the Cedar River. Based on the existing topographic survey, the site has a discharge pipe to the south. However, based on the topography of the project site and Union Ave NE, it appears the site stormwater would sheet flow to the northeast and southeast corners of the property if not intercepted by the three existing catch basins onsite. Storrnwater would theoretically flow offsite onto Union Ave NE and the northern portion of the site would drain north towards NE 4`" PL, while the southern portion of the site would drain south on Union Ave NE towards NE 4`" St. Based on the shallow depth of the existing storm drain lines to the south of the property p g p p Y on Union Ave NE and the physical constraints of the site, the project is proposing to discharge to the stormwater system to the north of the site on NE 4"' PL. No downstream impacts are anticipated as a result of the proposed improvements. Core Requirement #2: Off-site Analysis All proposed projects must identify the upstream tributary drainage area and perforin a downstream analysis. Levels of analysis required depend on the problems identified or predicted. At a minimum, a Level 1 analysis must be submitted with the initial permit application. Response: The upstream and downstream analyses have been performed and are summarized on page 10 of this report. Core Requirement #3: Flow Control Proposed projects must provide runoff controls to limit the developed conditions peak rates of runoff to the pre -development peak rates for specific storm events based on the proposed project site existing runoff conditions. Response: Stormwater will be detained onsite and released to match the pre -developed durations for forested site conditions from 50% of the 2 -year up to the 50 -year flow, in addition to matching the forested site condition 2 -year and I0 -year peak storm events, as PAUAND Project # 10.1 13.001 Page 7 Firestone Technical Information Report Renton, Washington described in the Cit of Renton's Flow Control Duration Standard Matching Forested Site Y g Conditions. Core Requirement #4: Conveyance System All conveyance systems for proposed projects must be analyzed, designed and constructed for developed on-site runoff from the proposed project. Response: The proposed conveyance system has been designed to convey the 25 -year peak flow. The onsite water quality and detention ponds have one foot of freeboard. The flow control structure has been designed with an overflow "birdcage" rim in case of failure. In an emergency overflow condition, the detention pond would discharge stormwater to the east, across the northwest portion of the site, and to the City stormwater system on Union Ave NE. Core Requirement #5: Erosion/Sedimentation Control Pian All engineering plans for projects that propose to construct new, or modify existing drainage facilities, must include a plan to install measures to control erosion and sedimentation during construction and to permanently stabilize soil exposed during construction. Response: Erosion and sediment control requirements will be a part of the project construction documents. These measures will include methods to reduce erosion of onsite site soils and to prevent sediments from inadvertently leaving the project site. Core Requirement #6: Maintenance and Operation Maintenance of all drainage facilities constructed by a proposed project is the responsibility of the property owner. Response: An Operations and Maintenance Manual is included in this report. Core Requirement #7: Financial Guarantees and Liability Construction of any surface water facilities requires the posting of a bond with the City of Renton. tResponse: A Bond Quantities worksheet will be included with the final submittal of the construction documents. Core Requirement #8: Water Quality Proposed projects must provide water quality facilities to treat the runoff from those new and replaced pollution -generating impervious surfaces and pollution -generating pervious surfaces targeted for treatment. IResponse: The proposed project improvements include approximately 0.62 acres of new or replaced pollution -generating impervious surface. A water quality wetpond and StormFilter cartridge treatment system with CSF media will be constructed to provide Enhanced Basic Water Quality treatment for target surfaces onsite. IPACLAND Project # 10.1 1.3.001 Page. 8 I Firestone Technical Information Report Renton, Washington I Special Requirement #1: Other Adopted Area -Specific Requirements Response: At this time, the project site is not known to be under any other adopted area - specific requirements. Special Requirement #2: Flood Hazard Area Delineation Response: The project site is not within a flood hazard area. Special Requirement #3: Flood Protection Facilities Response: The proposed project will not rely on an existing flood protection facility or construct a new flood protection facility. Special Requirement #4: Source Controls Response: Water quality source controls will be applied in accordance with the King County Stormwater Pollution Prevention Manual and Renton Municipal Code IV. A Pollution Prevention Plan for the Firestone site has been included on page 25 of this report. Special Requirement #S: Oil Control p q Response: The proposed building includes an oil/water separator which drains to the sanitary sewer to collect petroleum productions before entering the site parking areas. Additionally, the flow control structure at the outlet of the detention pond includes a downturn elbow to prevent the release of oils into the City of Renton stormwater system. 1 1 1 IPACLAND Project # 10.113.001 Page 9 I Firestone Technical Information Deport Renton, Washington J s Upstream Analysis Based on topographic survey, there is minimal tributary area to this site. NE 4th Place to the north and Union Ave NE to the east intercept stormwater before it reaches the site. Additionally, the existing topography surrounding the site prevents any significant amount of run-on. The upstream basin for the proposed connection on NE 4"' Place to the City of Renton system consists of only one upstream catch basin. Based on the size of the 12" storm drain pipe, this conveyance system is believed to have sufficient capacity for the proposed project's mitigated stormwater discharge, which less than 0.1 cfs in the 100 -year peak event. Downstream Analysis A downstream analysis of the existing drainage system was performed on January 14, 2011 by Jeff Chambers, P.E. of PACLAND. Currently runoff is intercepted onsite by three catch basins and discharges the site to the south via an 8" storm pipe. The stormwater enters the municipal stormwater system in Union Ave NE. This system continues south to NE 4`h St. The City of Renton stormwater maps indicate that the conveyance system flows east on NE 4'}' St. It is assumed that the stormwater discharges from the City of Renton municipal system into Maplewood Creek and then the Cedar River. The stormwater conveyances stem on NE 4'h Place flows west to a private detention vault Y and flow control facility located east of Queen Ave NE. According to the City of Renton stormwater maps, this vault discharges to another private flow control tank before conveying stormwater to the south on Queen Ave NE towards NE 4`h Street. It is believed that stormwater then flows west and south eventually discharging to the Cedar River. The design basin sizes for the private stormwater detention vault and tank downstream of NE 4" PL, near Queen Ave NE, are not known at this time. Because the fully forested site conditions assumed in design of this project, which will be matched in the developed stormwater system, discharge a 100 -year peak of less than 0.1 cfs, it is believed that this downstream system has reasonable capacity for the project site stormwater discharge. Evidence of Existing or Predicted Problems There is no visible evidence of drainage problems on or near the project site. No drainage problems are predicted as a result of the proposed improvements. PACLAND Project # 10.113.001 Page 10 J I r Firestone Technical Information Report Renton, Washington The City of Renton Amendment to the 2009 King County Surface Water Design Manual requires peak runoff control such that the post -developed durations match that of the pre - developed site for 50% of the 2 -year through the 50 -year storm events, as well as matching the pre -developed 2 -year and 10 -year peak discharge rates. The City of Renton Amendment applies flow control standards based on geographic areas, as determined by the Flow Control Application Map (see Appendix B). The project site lies within the Flow Control Duration Standard — Matching Forested area. This area requires matching of existing pre -developed peak storm durations, assuming that the pre -developed condition of the site is completely forested. The analysis below matches the forested condition described in the City of Renton Amendment. Hydrologic Analysis The King County Runoff Time Series (KCRTS) program using a historic 1 -hour duration in the Sea -Tac rainfall region (location scale factor ST -1.0) was used to model runoff. The detailed KCRTS outputs have been included in Appendix D. Existing Site Hydrology The existing site condition (1.22 acres) under the fully forested pre -developed condition is shown below: Table 6 Pre -developed (Forested) Site Conditions Area Condition Soil/Land Cover Type 1.22 AC Forest Till Forest Table 7 Pre -developed (Forested) Peak Runoff Rate Event Rate 50% 2 -year 0.015 cfs 50 -year 0.085 cfs 100 -year 0.097 cfs Developed Site Hydrology The developed site condition is provided below: Table 8 Developed Site Conditions Area Condition Soil/Land Cover Type 0.80 AC Pave mentlRooftop Impervious 0.42 AC Landscaping Till Soil IPAUAND Project # 10.113.001 Page 11 1 i� 1 J r Firestone Technical Information Report Table 9 Developed Peak Runoff Rate (Unmitigated) Event Rate 50% 2 -year 0.113 cfs 50 -year 0.406 cfs 100 -year 0.444 cfs Renton, Washington Retention/Detention System for Matching forested Site Conditions The post developed 100 -year peak runoff rate for the site differs by 0.35 cfs from the forested condition. A flow control facility is required to detain site runoff and release it at the matched durations of the pre -developed forested condition, shown in Table 7 above. A pond was sized using KCRTS to determine the required detention volume for the proposed site conditions. Based on the proposed finish grades and existing storm drain inverts in NE 4'h Place, it was determined that approximately 4.0' of active storage would be available within the detention pond. Using the existing and proposed site parameters listed above in Tables 7 and 9, the following detention requirements were calculated: Table 10 Detention Facility Details Orifice Orifice Size Bottom 1 3 7164" 397.5' 2 Bottom Elevation Live Volume Volume Detention Area of Live Storage Required Provided Facility (SF) Storage Depth (CF) (CF) Pond 2810 397.50 4.0' 16,572 _ 17,314 Table 11 Flow Control Structure Details Orifice Orifice Size Elevation 1 3 7164" 397.5' 2 1-5116" 400.5 Overflow 12" Diameter 401.5' Emergency Overflow Birdcage Structure 402.5' Approximately 16,572 cubic feet of stormwater detention is required to meet the City of Renton Flow Control Duration Standard Matching Forested Condition for this site. A flow control structure will be utilized at the outlet from the detention pond to control release rates to the municipal system. The details of the flow control structure are shown in Table 11 above and in Appendix D_ PACLANn Project # 10.113.001 Page 12 I 1 1 1 1 1 Firestone Technical Information Report Renton, Washington The mitigated developed peak discharge rates from the flow control structure are shown below in Table 12. Although there are slight increases in the mitigated discharge peaks above the predeveloped rates for the 50 and 100 -year events shown in Table 7, the KCRTS analysis shows that the output duration curve does not exceed the pre -developed target duration curve by more than 10% at any point, which meets the Flow Control Duration Standard Matching Forested Site Conditions requirements. The KCRTS duration analysis shows that the maximum positive excursion is 8.7% and no more than half of the deviation from the target duration curve is above the target duration, which also indicates an acceptable pond and flow control design. The full KCRTS analysis is included in Appendix D. Table 12 Developed Peak Runoff Rate (Mitigated) Event Rate 50% 2 -year 0.011 cfs 50 -year 0.094 cfs 100 -year 0.120 cfs Offsite Flows Approximately 1295 SF and 1410 SF of impervious surfaces at the north and south driveway entrances along Union Ave NE on the eastern portion of the site can not be captured by the onsite storm drainage system, due to limitations in the site grading and elevation of the stormwater discharge. Runoff from the combined 2705 SF of impervious surface will sheet flow offsite to the east into Union Ave NF and will be intercepted by catch basins in the City of Renton's public storm drain system on Union Ave NE. The design of the onsite detention system has been calculated to include all onsite areas, including those that cannot be captured. The over -detention is designed to mitigate for the runoff that cannot be captured onsite. Water Quality The project will follow the Enhanced Basic Water Quality menu for a two -facility treatment train in the King County Surface Water Design Manual, based on the commercial land use. A 3,455 CF wetpond followed by a StormFilter cartridge filter system with CSF media will fulfill the water quality treatment requirements. Per the Design Criteria for basic wetponds, section 6.4.1.2 of the King County Surface Water Design Manual, wetponds with a required wetpool volume less than 4,000 cubic feet may be singled celled. Therefore, the water quality wetpond shown in this design has only one cell. The water quality treatment design volumes and rates are shown below in Tables 13 and 14. The water quality sizing details are show in Appendix E. PACLAND Project # 10.113.001 Page 13 Firestone Technical Information Report Renton, Washington Table 13 Water Quality Required Volume (Wetpond) Facility Type WQ Volume Required WQ Voume Provided Basic Wetpond 3,378 CF 3,455 CF Table 14 Water Quality Volume (StormFilter) Facility Location Return Period WQ Design Flow (cfs) Preceding detention 35% of developed 2 -yr peak flow rate 0.103 The sizing for the StormFilters is based on the requirements outlined in Section 6.5.5 of the 2009 King County Surface Water Design Manual and sizing from Contech based on measured treatment capabilities of the units. A summary of the StormFilter sizing is in Table 15 below: Table 15 StormFilter Details Number of Drop Required Inlet to Invert in/ Treatment/Peak Cartridges Outlet Invert Out Flow Rate 5 1.8` (LowDrop Cartridges) 399.501 0.103 cfs/ 0.943 397.70 cfs The StormFilter manhole is located near the edge of the parking field for maintenance access and replacement of the CSF media cartridges. PncLAND Project # 10.1 13.001 Page 14 F-, 1 1 1 Firestone Technical Information Report Renton, Washington Conveyance Per the 2009 King County Surface Water Design Manual, Section 4.2.1.2, the on-site stormwater conveyance is calculated based on gravity flow analysis of the piping network. Peak runoff associated with a 25 -year storm event has been determined to be adequate. Uniform Flow Analysis utilizing Manning's equation was employed with a Manning's "n" value of 0.012. Manning's equation - Q= 1.4Y xAxR23xS112 With: Q =Flow (CFS) n = Manning's Roughness Coefficient (0.012) A = Flow Area (SF) R = Hydraulic Radius = Area /Wetted Perimeter (LF) S = Slope of the pipe (ft/ft) The proposed conveyance system will adequately convey the 25 -yr event, and all proposed storm pipes and swales are to be designed such that their capacity meets or exceeds that required during a 25 -year event. Additionally, the overflow from a 100 -year runoff event will not create or aggravate a severe flooding problem or severe erosion problem. 100 -Year Flood/Overflow Condition Review of the most recent FIRM maps indicates that the project site lies within the Zone X, which is determined to be outside of the 100 -year flood plain. 1 In the event of a larger storm, it is unlikely that the system would fail. Based on a review of the site and immediate surroundings, the overflow of the stormwater conveyance system would allow surface water to sheet flow to the public storm system northeast of the site in Union Ave NE. 11 PACLAND Project # 10.113.001 Page 15 Firestone Technical Information Report Renton, Washington An Infiltration Feasibility Study was prepared by Otto Rosenau & Associates, Inc., dated January 17, 2011, and is discussed in the Project Overview section of this report. The complete Otto Rosenau & Associates study is included in Appendix F. PAUAND Project # 10.1 13.001 Page 16 Firestone Technical information Report Renton, Washington The project site lies within Lower Cedar River Basin. PACLAND Project # 10.1 13.001 Page 17 Firestone Technical Information Report Renton, Washington The following governmental approvals or permits will likely be required for this project: • City of Renton Site Plan Review • City of Renton Building Permit • Washington State Department of Ecology NPDES Permit • Sewer Permit • Water Permit These permits will require approval by the City of Renton Planning Division, King County, or the Department of Ecology. PAUAND Project # 10.113.001 Page 18 Firestone Technical Information Report Renton, Washington The following items will be submitted upon approval of the Building Permit plans: • Site Improvement Band Quantity Worksheet • Declaration of Covenant for Maintenance and Inspection of Flow Control BMPs PAcLAND Project # 10.1 13.001 Page 19 Firestone Technical information Report Renton, Washington All erosion and sediment control measures shall be governed by the requirements of the City of Renton and the Washington State Department of Ecology. A temporary erosion and sedimentation control plan will be prepared to assist the contractor in complying with these requirements. The Erosion and Sediment Control (ESC) plan will be included with the construction plans. PA( -LAND Project # 10.1 13.001 Page 20 Firestone Technical Information Report Renton, Washington Maintain Stormwater Facilities The owner or operator of the project shall be responsible for maintaining the Stormwater facilities in accordance with local requirements. Proper maintenance is important for adequate functioning of the stormwater facilities. The following maintenance program is recommended for this project: Maintenance Checklist for Catch Basins and Inlets Frequency Drainage Problem Conditions To Check For Conditions That Should Exist System Feature M'S General Trash, debris, and Trash or debris in front of the No trash or debris located sediment in or on catch basin opening is blocking immediately in front of catch basin capacity by more than 10%. basin opening. Grate is kept clean and allows water to enter. M Sediment or debris (in the basin) No sediment or debris in the that exceeds 113 the depth from catch basin. Catch basin is the bottom of basin to invert of the dug out and clean. lowest pipe into or out of the basin, N1,s Trash or debris in any inlet or pipe Inlet and Outlet pipes free of blocking more than 113 of its trash or debris. height_ M Structural damage Corner of frame extends more than Frame is even with curb. to frame and/or top 3/a inch past curb face into the slab street (if applicable). M Top slab has holes larger than 2 Top slab is free of holes and square inches or cracks wider than cracks. 1/1 inch (intent is to make sure all material is running into the basin). M Frame not sitting flush on top slab, Frame is sitting flush on top i.e., separation of more than 3'Y4 slab. inch of the frame from the top slab. A Cracks in basin Cracks wider than % inch and Basin replaced or repaired to walls/bottom longer than 3 feet, any evidence of design standards. Contact a soil particles entering catch basin professional engineer for through cracks, or maintenance evaluation. person judges that structure is unsound. A Cracks wider than % inch and No cracks more than 1/4 inch longer than 1 foot at the joint of wide at the joint of any inlet/oudel pipe or any inlet/outlet pipe. Contact a evidence of soil particles entering professional engineer for catch basin through cracks. evaluation. A settlement/ Basin has settled more than 1 inch Basin replaced or repaired to misalignment or has rotated more than 2 inches design standards. Contact a out of alignment. professional engineer for evaluation. It you are unsure whether a problem exists, please contact a Professional Engineer. Comments: A � Annual (March or April, preferred) M = Monthly (see schedule) 5 — After major storms (use 1 -inch in 24 hours as a guideline) PAUAND Project # 10.113.00 1 Page 21 Firestone Technical Information Report Renton, Washington (CONTINUED) M's Drainage Fire hazard of other Presence of chemicals such as No color, odor, or sludge. System pollution natural gas, oil, and gasoline. Basin is dug out and clean. Feature Obnoxious color, odor, or sludge M General Missing or broken n oted. Fence is mended or shrubs M,S Outlet pipe is Vegetation or roots growing in No vegetation or root growth clogged with inletloutlet pipe joints that are present. M,S vegetation more than 6 inches tall and less Replace soil under fence so that than 6 inches apart_ no opening exceeds 4 inches in if you are unsure whether a problem exists, please contact a Professional Engineer. Maintenance Checklist for Fencing/Shrubbery Screen/Dther Candscaainm Frequency Drainage Problem Conditions To Check For Conditions That Should Exist System Feature M General Missing or broken Any defect in the fence or screen Fence is mended or shrubs parts/dead shrubbery that permits easy entry to a facility replaced to form a solid barrier to entry. M,S Erosion Erosion has resulted in an opening Replace soil under fence so that under a fence that allows entry by no opening exceeds 4 inches in people or pets. height. M Unruly vegetation Shrubbery is growing out of control Shrubbery is trimmed and weeded or is infested with weeds. to provide appealing aesthetics. Do not use chemicals to control weeds. A Wire Damaged parts Posts out of plumb more than 6 Posts plumb to within 1-112 Fences inches. inches of plumb. A Top rails bent more than 6 inches. Top rail free of bends greater than 1 inch. A Any part of fence (including posts, Fence is aligned and meets design top rails, and fabric) more than 1 foot standards. out of design alignment. A Missing or loose tension wire_ Tension wire in place and holding fabric. A Missing or loose barbed wire that is Barbed wire in place with less sagging more than 2-1/2 inches than $'4 -inch sag between posts, between posts. A Extension arm missing, broken, or Extension arm in place with no bent out of shape more than 1-112 bends larger than 1/4 inch. inches. A Deteriorated paint or Part or parts that have a rusting or Structurally adequate posts or protective coating scaling condition that has affected parts with a uniform protective structural adequacy. coaling. M Openings in fabric Openings in fabric are such that an No openings in fabric. 8 -inch diameter ball could fit through. If you are unsure whether a problern exists, please contact a Professional Engineer. Comments: A = Annual (March or April, preferred) M — Monthly (see schedule) S = After major storms (use 1 -inch in 24 hours as a guideline) PACLAND Project # 10.1 13.001 Page 22 Firestone Technical Information Report Renton, Washington Maintenance Checklist for Conveyance Svstems (Pines, Ditches and Swales) Frequency Drainage Problem Conditions To Check For Conditions That Should Exist System Feature M'S Pipes Sediment & Accumulated sediment that exceeds Pipe cleaned of all sediment and debris 201!0 of the diameter of the pipe. debris. M Vegetation Vegetation that reduces free movement All vegetation removed so water of water through pipes. flows freely through pipes. A Damaged Protective coating is damaged; rust is Pipe repaired or replaced. (rusted, bent, causing more than 500/4 deterioration to or crushed) any part of pipe. M Any dent that significantly impedes Pipe repaired or replaced. flow (i.e., decreases the cross section area of pipe by more than 20%). M Pipe has major cracks or tears allowing Pipe repaired or replaced. groundwater leakage. M'S Open Trash & debris Dumping of yard wastes such as grass Remove trash and debris and Ditches clippings and branches into basin. dispose as prescribed by the Unsightly accumulation of County. nondegradable materials such as glass, plastic, metal, foam, and coated paper_ M Sediment Accumulated sediment that exceeds Ditch cleaned of all sediment and buildup 20% of the design depth. debris so that it matches design, A Vegetation Vegetation (e.g,, weedy shrubs or Water flows freely through saplings) that reduces free movements ditches. Grassy vegetation should of water throu h ditches. be left alone. M Erosion Cheek around inlets and outlets for Find caused of erosion and damage to signs of erosion_ Check berms for signs eliminated them. Then slopes slopes of sliding or settling. Action is needed should be stabilized by using where eroded damage over 2 inches appropriate erosion control deep and where there is potential for measure(s); e.g., rock continues erosion. reinforcement, planting grass, compaction. A Rock lining Maintenance person can see native soil Replace rocks to design standard_ out of place or beneath the rock lining. missing (if applicable) Varies Catch See Catch Basins Checklist_ See Catch Basins Checklist. basins M,S Swale's Trash & debris See above for Ditches. See above for Ditches. M Sediment See above for Ditches. Vegetation may need to be buildup replanted after cleaning. M Vegetation not Grass cover is sparse and seedy or areas Aerate soils and reseed and mulch growing or are overgrown with woody vegetation. bare areas. Maintain grass height overgrown at a minimum of 6 inches for best stormwater treatunent. Remove woody growth, recontour, and reseed as necessary. M'S Erosion See above for Ditches. See above for Ditches. damage to slopes M Conversion by Swale has been filled in or blocked by If possible, speak with homeowner homeowner to shed, woodpile, shrubbery, etc. and request that swale area be incompatible restored. Contact the County to use report problem if not rectified voluntarily. A Swale does not Water stands in swale or flow velocity A survey may be. needed to check drain is very slow. Stagnation r><curs. grades. Grades need to be in 1- 5% range. if possible. If grade is less than 1 ! underdrains may need to be Installed. PAUAND Project # 10.113.001 Page 23 Firestone Technical Information Report Maintenance Checklist for Grounds (Candscaainm) Renton, Washington frequency Drainage 4 Problem Conditions To Check For Conditions That Should Exist System Feature M General Weeds Weeds growing in more than 20% of Remove trash and debris and (nonpoisonous) the landscaped area (trees and shrubs dispose as prescribed by the only)._ County. M Insect hazard Any presence of poison ivy or other Ditch cleaned of all sediment poisonous vegetation or insect nests. and debris so that it matches M Poisonous Any poisonous vegetation which may design. M's Trash or litter Dumping of yard wastes such as grass Remove trash and debris and clippings and branches onto grounds. dispose as prescribed by the Unsightly accumulation of County. nondegradable materials such as glass, approval from the Count . M,S Fire hazard or plastic, metal, foam, and coated paper - Find sources of pollution and M's Erosion of Noticeable rills are seen in landscaped Causes of erosion are Ground Surface areas. identified and steps taken to slow down/spread out the M Vegetation not For grassy ponds, grass cover is sparse water. Eroded areas are filled, growing or is and weedy or is overgrown. For contoured, and seeded. A Trees and Damage limbs or parts of trees or shrubs that are Trim trees/shrubs to restore shrubs split or broken which affect more than shape. Replace trees/shrubs 25% of the total foliage of the tree or with severe damage. shrub. plants in bare areas. Contact the M Trees or shrubs that have been blown Replant tree, insperting for down or knocked over. injury to stem or roots. Replace if severely damaged. A Trees or shrubs which are not Place stakes and rubber -coated adequately supported or are leaning ties around young trees/shrubs over, causing exposure of the roots. for support. It you are unsure whether a problem exists, please contact a Professional Engineer, Comments: A = Annual (March or April, preferred) M = Monthly (see schedule) S = After major storms fuse 1 -inch in 24 hours as a guideline) Maintenance Checklist for Detention Ponds Frequency Drainage Problem Conditions To Check For Conditions That Should Exist System Feature M,S General Trash & debris Dumping of yard wastes such as grass Remove trash and debris and buildup in pond clippings and branches into basin. dispose as prescribed by the County. Unsightly accumulation of nondegradable materials such as glass, lactic, metal, foam, and coated paper. M Poisonous Any poisonous vegetation which may Remove poisonous vegetation. Do vegetation constitute a hazard to the public. not spray chemicals on vegetation Examples of poisonous vegetation without obtaining guidance from the include: tansy ragwort, poison oak, Cooperative fxtension Service and stinging nettles, devilsclub. approval from the Count . M,S Fire hazard or Presence of chemicals such as natural Find sources of pollution and pollution gas, oil, and gasoline, obnoxious color, eliminate them. Water is free from odor, or sludge noted. noticeable color, odor, or contamination. M Vegetation not For grassy ponds, grass cover is sparse For grassy pends, selectively thatch, growing or is and weedy or is overgrown. For aerate, and reseed ponds. Crass overgrown wetland ponds, plants are sparse or cutting unnecessary unless dictated invasive species are present. by aesthetics. For wetland ponds, hand -plant nursery grown wetland plants in bare areas. Contact the Cooperative Fxlension Service for direction on invasive species such as purple. loosesirife and reed Canary grass. Pond bottoms should have PAUAND Project # 10.113.001 Page 24 Firestone Technical Information Report Renton, Washington If you are unsure whether a problem exists, please contact a Professional Engineer. Comments: A — Annual (March or April, preferred) M = Monthly (see schedule) S = After major storms (use 1 -inch in 24 hours as a guideline) PACLAND Project # 10.113.001 Page 25 uniform dense coverage of desired plant species. M Rodent holes Any evidence of rodent holes if facility Rodents destroyed and dam or berm is acting as a dam or berm, or any repaired. Contact the Tacoma - evidence of water piping through dam Pierce County Cooperative or berm via rodent holes. Extension Service for guidance. M Insects When insects such as wasps and Insects destroyed or removed from hornets interfere with maintenance site. Selectively cultivate trees such activities, or when mosquitoes become as alders for firewood. a nuisance. A Storage Sediment A soil texture test indicates facility is Sediment is removed and/or facility buildup in not working at its designed capabilities is cleaned so that infiltration system system or was incorrectly designed. works according to design. A sediment trapping area is installed to reduce sediment transport into infiltration area. A Storage area A soil texture test indicates facility is Additional volume is added through drains slowly not working at its designed capabilities excavation to provide needed (more than 48 or was incorrectly designed. storage_ Soil is aerated and hours) or rototilled to improve drainage. overflows Contact the County for information on its requirements regarding excavation. M Sediment Any sediment and debris filling area to Clean out sump to design depth. trapping area 10% of depth from sump bottom to bottom of outlet pipe or obstructing flow into the connector pipe. One Time Sediment Stormwater enters infiltration area Add a trapping area by constructing trapping area directty without treatment. a sump for settling of solids. not present Segregate settling area from rest of facility. Contact the County for guidance. M Rock Sediment and By visual inspection little or no water Replace gravel in rock filter. filters debris flows through filter during heavy rain storms. If you are unsure whether a problem exists, please contact a Professional Engineer. Comments: A — Annual (March or April, preferred) M = Monthly (see schedule) S = After major storms (use 1 -inch in 24 hours as a guideline) PACLAND Project # 10.113.001 Page 25 t 1 1 Firestone Technical Information Report Renton, Washington This plan is intended to assist the local store manager and assistant manager in addressing pollution in parking, loading, and other outdoor portions of their store locations. IN CASE OF A SPILL, WHICH HAS DISCHARGED TO THE STORMWATER SYSTEM, CONTACT: WASHINGTON STATE DEPARTMENT OF ECOLOGY (360) 407-6437 IN CASE OF A SPILL, WHICH HAS DISCHARGED TO THE SANITARY SEWER SYSTEM, CONTACT: CITY OF RENTON MAINTENANCE SERVICES DIVISION (425) 430-7400 GOAL: Avoid contamination of stormwater run-off by preventing pollution from interacting with rain run-off (Source Control) and to prevent accidental discharges to the sanitary sewer system. BACKGROUND: The main source of stormwater pollutants is the parking lot. Theon -site stormwater system collects surface water run-off through a concrete swale in the parking lot and then along the western curb in the parking lot. After being conveyed along the curb in the concrete gutter, the run-off discharges to a water quality sediment pond, a cartridge filtration system in a manhole and then into detention pond. The detention pond holds the run-off until it is slowly released into the City of Renton municipal stormwater system. Contaminated stormwater can be discharged to local streams and rivers if proper maintenance is not followed. Similarly in recent years, it has been realized that intentional and accidental discharges of certain toxic and hazardous chemicals into the sanitary sewer have had harmful effects to the environment and to the receiving wastewater treatment plant. This store has been designed to not discharge any hazardous chemicals to the sanitary sewer; hence, in the event of an accidental spill this pollution prevention plan has been developed. Vehicle Maintenance: Delivery vehicles are not typically fueled, washed or maintained on-site, In the event one of these operations is required, care shall be taken to prevent spilling on pavement. In the event a spill occurs, reference Spill Protection below. Roof Run-off: Run-off from the roof discharges directly to the City of Renton stormwater system and does not pass through the water quality devices onsite. It is important that roof maintenance takes this into consideration and keeps a clean and safe working environment. ' Storage of Materials On-site: Long-term storage of hazardous materials outside the building is not anticipated. However, in the event that hazardous materials, including auto maintenance fluids, hydraulic fluid, cleaners, batteries, propane and other fuels, are 1 stored on-site, place these materials on a wooden pallet above ground with a plastic tarp I PAcLAND Project # 10.1 13.001 Page 26 1 1 t Firestone Technical Information Report Renton, Washington underneath. The edges of the tarp shall be elevated to create a containment area to collect possible spills. Employee Training: Store manager shall train key staff to address spills and on-site storm system operation. Training will include identification of location of spill response materials. Routine Maintenance: Store manager shall provide routine maintenance of the storm system as follows. It is intended that this work would be handled as part of the larger site maintenance program typically handled through subcontractors and has been broken down accordingly. Street - Sweep parking lot regularly to prevent silt and Work to be Sweeper / other pollutants from reaching the sediment completed on Maintenance pond a monthly Contractor - Remove garbage and debris from parking lot basis or as and landscaping areas. needed (min — 2 x per year) Landscape - Remove weeds. Work to be Maintenance - Use pesticides, herbicides or fertilizer sparely completed on Contractor avoid amounts which can enter the runoff a monthly /leach into the stormwater system. basis or as - Prevent erosive conditions in landscape areas. needed. Industrial - Clean sumps (dead storage in bottom of inlets) Work to be Maintenance using a vacuum truck. completed on Contractor - Remove sediment build-up from Settling Pond, a yearly basis and Detention Pond. — typically at the end of Summer. Miscellaneous - Paint "Dump No Waste - Drains to As needed to Maintenance Groundwater" at any Catch Basin Inlets. for maintenance The vendors andlor store manager should keep regular records of maintenance activities. Emergency Spill Response: All facilities contain materials that are harmful to the environment. The following is a summary of materials that could potentially be involved, in an accidental spill outside the store. Any material containing a caution label should be addressed in accordance with manufacturers recommendations and the material safety data sheets, human life should always be taken into consideration as a priority. Store manager shall maintain a spill control plan (this plan) that includes training and maintenance of a spill response kit. This kit shall include the following items: 1. Absorbent granular or powdered material, such as "kitty litter", for absorbing and neutralizing alkaline and acid liquids. 2. Appropriately lined drums to discard waste material 3. Absorbent pads 1 PACLAND Project # 10.1 13.001 Page 27 Firestone Technical Information Report Renton, Washington 4. This Spill Response Manual Kits should be placed in a convenient location, such as adjacent to the loading area. Label kits with "EMERGENCY SPILL KIT" signage. Follow the following basic procedures in the event of a spill. PAcLAND Project # 10.113.001 Page 28 1 Firestone Technical Information Report Renton, Washington Hydraulic Fluid Leak Place sand or absorbent material (kitty litter) over spill from Compactor area. Sweep clean and discard used absorbent material 4D in a garbage container to be taken to a proper waste 1 %MR facility. Repeat until spill is cleaned. if event occurs during rain event, cover with plastic until weather allows for proper clean up. Automobile Fuel or See Hydraulic Fluid Leak above Oil Spill Cleaner or Solvent • See Hydraulic Fluid Leak above Spill IN CASE OF A SPiLL, WHICH HAS DISCHARGED TO THE STORMWATER SYSTEM, CONTACT. WASHINGTON STATE DEPARTMENT OF ECOLOGY (360) 407-6437 IN CASE OF A SPILL, WHiCH HAS DISCHARGED TO THE SANITARY SEWER SYSTEM, CONTACT. CiTY OF RENTON MAINTENANCE SERVICES DIVISION (425) 430-7400 This plan is intended to be utilized as part of the Renton, WA Firestone operated in King County, Washington as required by King County ordinance. Operator of this stormwater facility should use common sense in managing operations to prevent pollution of the environment Future code revisions by King County may require operator to adhere to other criteria or programs. This Plan prepared by. " 0 Im", 4D 1 %MR 1 1505 Westlake Ave. N T 206.522.9510 Suite 305 F 206.522.8344 Seattle, WA 98109 www.pacland.com Contact: Jeff Chambers, PE February 2011 I PAUAND Project # 10.113.001 Page 29 41 CONTECH sTORMATER 1 s�o�sr StormFilter Inspection and Maintenance Procedures The ttprmwi4-KUMR�,+"rsrse 4 StormFilter- fl 11 1 1 1 1 t Maintenance Guidelines The primary purpose of the 5tormwater Management StormFilterfr' is to filter out and prevent pollutants from entering our waterways. Like any effective filtration system, periodically these pollutants must be removed to restore the StormFilter to its full efficiency and effectiveness. Maintenance requirements and frequency are dependent on the pollutant load characteristics of each site. Maintenance activities may be required in the event of a chemical spill or due to excessive sediment loading from site erosion or extreme storms. It is a good practice to inspect the system after major storm events. Maintenance Procedures Although there are likely many effective maintenance options, we believe the following procedure is efficient and can be implemented using common equipment and existing maintenance protocols. A two step procedure is recommended as follows: 1. Inspection Inspection of the vault interior to determine the need for maintenance. 2. Maintenance Cartridge replacement Sediment removal Inspection and Maintenance Timing At least one scheduled inspection should take place per year with maintenance following as warranted. First, an inspection should be done before the winter season. During the inspection the need for maintenance should be determined and, if disposal during maintenance will be required, samples of the accumulated sediments and media should be obtained. Second, if warranted, a maintenance (replacement of the filter cartridges and removal of accumulated sediments) should be performed during periods of dry weather. in addition to these two activities, it is important to check the condition of the StormFilter unit after major storms for potential damage caused by high flows and for high sediment accumulation that may be caused by localized erosion in the drainage area. It may be necessary to adjust the inspection/ maintenance schedule depending on the actual operating conditions encountered by the system. In general, inspection activities can be conducted at any time, and maintenance should occur, if warranted, in late summer to early fall when flows into the system are not likely to be present. Maintenance Frequency The primary factor controlling timing of maintenance of the StormFilter is sediment loading. A properly functioning system will remove solids from water by trapping particulates in the porous structure of the filter media inside the cartridges. The flow through the system will naturally decrease as more and more particulates are trapped. Eventually the flow through the cartridges will be low enough to require replacement. It may be possible to extend the usable span of the cartridges by removing sediment from upstream trapping devices on a routine as -needed basis in order to prevent material from being re -suspended and discharged to the StormFilter treatment system. Site conditions greatly influence maintenance requirements. StormFilter units located in areas with erosion or active construction may need to be inspected and maintained more often than those with fully stabilized surface conditions. The maintenance frequency may be adjusted as additional monitoring information becomes available during the inspection program. Areas that develop known problems should be inspected more frequently than areas that demonstrate no problems, particularly after major storms. Ultimately, inspection and maintenance activities should be scheduled based on the historic records and characteristics of an individual StormFilter system or site. It is recommended that the site owner develop a database to properly manage StormFilter inspection and maintenance programs. Prior to the development of the maintenance database, the following maintenance frequencies should be followed: Inspection One time per year After major storms Maintenance As needed, based on results of inspection (The average maintenance lifecycle is approximately 1-3 years) Per Regulatory requirement In the event of a chemical spill Frequencies should be updated as required. The recommended initial frequency for inspection is one time per year. StormFilter units should be inspected after major storms. Ll 1 C 1 t Sediment removal and cartridge replacement on an as needed basis is recommended unless site conditions warrant. Once an understanding of site characteristics has been established, maintenance may not be needed for one to three years, but inspection is warranted and recommended annually. Inspection Procedures The primary goal of an inspection is to assess the condition of the cartridges relative to the level of visual sediment loading as it relates to decreased treatment capacity. It may be desirable to conduct this inspection during a storm to observe the relative flow through the filter cartridges. If the submerged cartridges are severely plugged, then typically large amounts of sediments will be present and very little flow will be discharged from the drainage pipes. if this is the case, then maintenance is warranted and the cartridges need to be replaced. Warning: In the case of a spill, the worker should abort inspection activities until the proper guidance is obtained. Notify the local hazard control agency and CONTECH Stormwater Solutions immediately. To conduct an inspection: ;Important inspection should lae perm rfoed bya person who a amts+ar irvith tfye;nperat on and:con frguca6 tSrf"the :S3ormFilte`r treatment gni#: 1. If applicable, set up safety equipment to protect and notify surrounding vehicle and pedestrian traffic. 2. Visually inspect the external condition of the unit and take notes concerning defects/problems. 3. Open the access portals to the vault and allow the system vent. 4_ Without entering the vault, visually inspect the inside of the unit, and note accumulations of liquids and solids. 5. Be sure to record the level of sediment build-up on the floor of the vault, in the forebay, and on top of the cartridges. If flow is occurring, note the flow of water per drainage pipe. Record all observations. Digital pictures are valuable for historical documentation. 6. Close and fasten the access portals 7. Remove safety equipment. 8. If appropriate, make notes about the local drainage area relative to ongoing construction, erosion problems, or high loading of other materials to the system. 9. Discuss conditions that suggest maintenance and make decision as to weather or not maintenance is needed. Maintenance Decision Tree The need for maintenance is typically based on results of the inspection. The following Maintenance Decision Tree should be used as a general guide. (Other factors, such as Regulatory Requirements, may need to be considered) 1. Sediment loading on the vault floor. a. if >4" of accumulated sediment, maintenance is required. 2. Sediment loading on top of the cartridge. a. If > 1/4" of accumulation, maintenance is required. 3. Submerged cartridges. a. If >4" of static water in the cartridge bay for more that 24 hours after end of rain event, maintenance is required. 4. Plugged media. a. If pore space between media granules is absent, maintenance is required. 5. Bypass condition. a. If inspection is conducted during an average rain fall event and StormFilter remains in bypass condition (water over the internal outlet baffle wall or submerged cartridges), maintenance is required. 6. Hazardous material release. a. If hazardous material release (automotive fluids or other) is reported, maintenance is required. 7. Pronounced scum line. a. If pronounced scum line (say - 1/4" thick) is present above top cap, maintenance is required. S. Calendar Lifecycle. a. If system has not been maintained for 3 years maintenance is required. 3 1 1 1 1 1 1 1 1 Assumptions • No rainfall for 24 hours or more • No upstream detention (at least not draining into StormFilter) • Structure is online • Outlet pipe is clear of obstruction • Construction bypass is plugged Maintenance Depending on the configuration of the particular system, maintenance personnel will be required to enter the vault to perform the maintenance. Important: If vault entry is required, OSHA rules for confined space entry must be followed_ Filter cartridge replacement should occur during dry weather. It may be necessary to plug the filter inlet pipe if base flows is occurring. Replacement cartridges can be delivered to the site or customers facility. Information concerning how to obtain the replacement cartridges is available from CONTECH Stormwater Solutions. Warning: In the case of a spill, the maintenance personnel should abort maintenance activities until the proper guidance is obtained. Notify the local hazard control agency and CONTECH Stormwater Solutions immediately. To conduct cartridge replacement and sediment removal maintenance: 1. If applicable, set up safety equipment to protect maintenance personnel and pedestrians from site hazards. 2. Visually inspect the external condition of the unit and take notes concerning defects/problems. 3. Open the doors (access portals) to the vault and allow the system to vent. 4. Without entering the vautt, give the inside of the unit, including components, a general condition inspection. 5. Make notes about the external and internal condition of the vault. Give particular attention to recording the level of sediment build-up on the floor of the vault, in the forebay, and on top of the internal components. 6. Using appropriate equipment offload the replacement cartridges (up to 150 lbs. each) and set aside. 7. Remove used cartridges from the vault using one of the following methods: Method 1: A. This activity will require that maintenance personnel enter the vault to remove the cartridges from the under drain manifold and place them under the vault opening for lifting (removal). Unscrew (counterclockwise rotations) each filter cartridge from the underdrain connector. Roll the loose cartridge, on edge, to a convenient spot beneath the vault access. 4 Using appropriate hoisting equipment, attach a cable from the boom, crane, or tripod to the loose cartridge. Contact CONTECH Stormwater Solutions for suggested attachment devices. Important Care must be used to aVbi'd,'damagirtg the cartrrdges during removal and intalla#ion fhe cast of repairing components ciarnaged during maintenance v<iill be the, responsibility Pi.A e.owner unless CQNTECH Stormwater,Solutions peifprms.th0 rnarntenance acfrvrties and damage is'.nof related to drseharges to the system C Set the used cartridge aside or load onto the hauling truck. D. Continue steps a through c until all cartridges have been removed. Method 2: A. Enter the vault using appropriate confined space protocols. B. Unscrew the cartridge cap. C. Remove the cartridge hood screws (3) hood and float. D. At location under structure access, tip the cartridge on its side. 1 n LI 1 E. Set the empty, used cartridge aside or load onto the hauling truck. F. Continue steps a through e until all cartridges have been removed. 8. Rernove accumulated sediment from the floor of the vault and from the forebay_ This can most effectively be accomplished by use of a vacuum truck. 9. Once the sediments are removed, assess the condition of the vault and the condition of the connectors. The connectors are short sections of 2 -inch schedule 40 PVC, or threaded schedule 80 PVC that should protrude about 1 " above the floor of the vault Lightiy wash down the vault interior. a. If desired, apply a light coating of FDA approved silicon lube to the outside of the exposed portion of the connectors. this ensures a watertight connection between the cartridge and the drainage pipe. b. Replace any damaged connectors. 10. Using the vacuum truck hoom, crane, or tripod, lower and install the new cartridges. Once again, take care not to damage connections. 11. Close and fasten the door. 12. Remove safety equipment. 13. Finally, dispose of the accumulated materials in accordance with applicable regulations. Make arrangements to return the used empty cartridges to CONTECH Stormwater Solutions. 9 Related Maintenance Activities - Performed on an as -needed basis StormFiiter units are often just one of many structures in a more comprehensive stormwater drainage and treatment system. In order for maintenance of the StormFilter to be successful, it is imperative that all other components be properly maintained The maintenance/repair of upstream facilities should be carried out prior to StormFiiter maintenance activities. In addition to considering upstream facilities, it is also important to correct any problems identified in the drainage area. Drainage area concerns may include: erosion problems, heavy oil loading, and discharges of inappropriate materials. 1 J Material Disposal The accumulated sediment found in stormwater treatment and conveyance systems must be handled and disposed of in accordance with regulatory protocols. It is possible for sediments to contain measurable concentrations of heavy metals and organic chemicals (such as pesticides and petroleum products). Areas with the greatest potential for high pollutant loading include industrial areas and heavily traveled roads. Sediments and water must be disposed of in accordance with all applicable waste disposal regulations. When scheduling maintenance, consideration must be made for the disposal of solid and liquid wastes. This typically requires coordination with a local landfill for solid waste disposal. For liquid waste disposal a number of options are available including a municipal vacuum truck decant facility, local waste water treatment plant or on-site treatment and discharge. A RECYCLED ij PAPER OWIM4 i� Lel 800.925.5240 contechstormwater.com Support Drawings and specifications are available at contechstormwater.com. • Site-specific design support is available from our engineers. 82007 CONTECH Stormwater Solutions CONTECH Construction Products Inc, provides site solutions for the civil engineering industry. CONTECH's portfolio includes bridges, drainage, sanitary sewer, stormwater and earth stabilization products. For information on other CONTECH division offerings, visit contech-cpi.com or call 800.338.1122 Nothing in this catalog should be construed as an expressed warranty or an implied warranty of merchantability or fitness for any particular purpose. See the CONTECH standard quotation or acknowledgement for applicable warranties and other terms and conditions of sale. Inspection R-•. Date: Personnel: ` Location: System Size: System Type: Vault ❑ Cast -In -Place ❑ Linear Catch Basin ❑ Manhole [J Other ❑ Sediment Thickness in Forebay:_ Date: Sediment Depth on Vault Floor: Structural Damage: Estimated Flow from Drainage Pipes (if available): Cartridges Submerged: Yes ❑ No ❑ Depth of Standing Water: StormFilter Maintenance Activities (check off if done and give description) ❑ Trash and Debris Removal: ❑ Minor Structural Repairs: ❑ Drainage Area Report Excessive Oil Loading: Yes [] No [] Source: Sediment Accumulation on Pavement: Yes ❑ No ❑ Source: ' Erosion of Landscaped Areas: Yes ❑ No ❑ Source: Items Needing Further Work: Owners should contact the local public works department and inquire about how the department disposes of their street waste residuals. Other Comments: 1 ' Review the condition reports from the previous inspection visits. Date: Personnel: Location: ------System Size: ' System Type: Vault ❑ Cast -In -Place ❑ Linear Catch Basin ❑ List Safety Procedures and Equipment Used: IW I Manhole ❑ Other ❑ System Observations Months in Service: Oil in Forebay: Yes ❑ No ❑ Sediment Depth in Forebay: _ Sediment Depth Vault Floor: on Structural Damage: Drainage Area Report Excessive Oil Loading: Yes ❑ No ❑ Source: ' Sediment Accumulation on Pavement: Yes ❑ No ❑ Source: Erosion of Landscaped Areas: Yes ❑ No ❑ Source: ' 5tormFilter Cartridge Replacement p Maintenance Activities Trash and Debris: Yes ❑ No ❑ Details: 'Remove Replace Cartridges: Yes No E1 Details: Sediment Removed: Quantity Sediment Removed (estimate?): Yes ❑ No ❑ Details: of Minor Structural Repairs: Yes ❑ No ❑ Details: Residuals (debris, sediment) Disposal Methods: Notes: IW I Manhole ❑ Other ❑ Firestone Technical Information Report Renton, Washington Appendix A — Drainage Basin Exhibits PACLAND Project #10-113.001 Page 1 NE 4th PL S' \ � y -� �Q a Fw� ST10RT PIAT L6T � 1 ` I 57.000. T. l X1.1 I � p �1 �+ffLLff SI CHARGE/TO 1 CI TORM S TEM j !1 LEGEND EXISTING PIPE FLOW EXISTING SURFACE FLOW BASIN BOUNDARY _ , , _ _ 1505 Westlake Ave. N. T (206) Suite 305 F (206) Seattle, WA 98109 W".P FIRESTONE RENTON, WASHINGTON EXHIBIT A EXISTING BASIN EXHIBIT SC1 - W O-1 2 yy� RJ L 1505 WeWake Sinha 305 Seattle, WA 98149 1l 21, NE 4th PL sD PROPOSE SITE DISCHA9�L TO CITY tTORM SYSTEM �Ill�ll �Ilttl •� �,- �. 1k I �• �.Y�.ns�gsv�ea:�w.w.� C 1 e S� 1111{l1l1 I f0111l� l 1, 1 Al PROPOSED SURFACE FLOW BASIN BOUNDARY FIRESTONE RENTON, WASHINGTON r PROPOSED ROrO. B 1 EXHIBIT �. E Firestone Technical Information Report Renton, Washington Appendix B - Flow Control Application Map PACLAND Project #10.11.3.001 Page 2 f. S 68th �znd PROPOSED FIRESTONE > PROJECT SITE LOCATION Reference 11-A L >- Flow Control Standards Peak Rate Flow Control Standard (Existing Site Conditions) Flow Control Duration Standard (E)isting SHe Conditions) - Flow Control Duration Standard (Forested Conditions) Renton City Limits �••� Potential Annexation Area l f r � i e sF � fi fi S��sl s 7zisiPl S• 5E 121 p Flow Control Application Map Printed 1114/2010 City of .r 0 1 2 -- r! :F i r j 1 Miles � � 15014 PlI H. r 151V 271T St: SE 170tk SW 341h 167 �` 5 a 1 l W 391h i 172n 'R' ¢ �`•7 1 C sty 51 ry i... •[ SF 1 SE 180th Sl _ l 861h St h� '1801ha 180th way �'FF. S 168 w I�4t t a `Yt S w 8 AS2 1 m 199th Iy - o S 001 St _ •� c )elm Rd c a 4 m 5< 1 �., a S q 1,1 m S O41h Flow Control Application Map Printed 1114/2010 City of .r 0 1 2 -- r! :F i r j 1 Miles Firestone Technical Information Report Renton, Washington Appendix C — Forested and Proposed Runoff Calculations PACLAND Project #10.113.001 Page 3 Flow Frequency Analysis LogPearson III Coefficients --- - --------- --------- _---= --------------- Time Series_File:rnfs------�_ _predee.tsf 34ean`- 1.530-StdDeu- 0.233 Project I.ocation:Sea-Tac Skew= -0.132 ---Annual Peak Flow Rates--- -----Flog Frequency Flow Rate Rate Rank Time of Peak - Peaks - bank Return Prob (CFS) (CFS) Period 0.036 16 2/16/49 22:00 0.082 1 69.50 0.989 0.028 0.070 5 3/03/50 16:00 0.077 2 32.13 0.969 ' 0.077 2 2/09/51 18:00 0.073 3 19.58 0.949 1/06/66 0.024 32 1/30/52 9:00 0.072 4 14.06 0.929 14:00 0.019 0.028 42 28 1/18/53 1/06/54 19:00 5:00 0.070 0.060 5 6 10.99 9.01 0.909 0.889 0.048 10 2/07/55 21:00 0.058 7 7.64 0.869 0.041 13 12/20/55 17:00 0.052 8 6.63 0.849 0.032 21 12/09/56 15:00 0.048 9 5.86 0.829 ' 0.034 20 1/16/58 20:00 0.048 10 5.24 0.809 0.028 24 1/24/59 2:00 0.048 11 4.75 0.789 0.052 8 11/20/59 21:00 0.041 12 4.34 0.769 ' 0.028 23 2/24/61 16:00 0.041 13 3.99 0.749 0.017 44 1/03/62 1:00 0.040 14 3.70 0.729 0.022 36 11/25/62 14:00 0.037 15 3.44 0.709 0.028 25 1/01/64 19:00 0.036 16 3.22 0.690 ' 0.020 39 11/30/64 12:00 0.036 17 3.03 0.670 0.021 38 1/06/66 3:00 0.036 18 2.85 0.650 0.048 11 1/19/67 14:00 0.035 19 2.70 0.630 0.036 0.028 22 2/03/68 23:00 0.034 20 2.56 0.610 19 0.028 26 12/03/68 17:00 0.032 21 2.44 0.590 1/24/84 0.023 34 1/13/70 23:00 0.028 22 2.32 0.570 ' 0.019 0.058 41 7 12/06/70 2/28/72 8:00 3:00 0.028 0.028 23 24 2.22 2.13 0.550 0.530 0.026 29 1/13/73 5:00 0.028 25 2.04 0.510 0.028 27 1/15/74 2:00 0.028 26 1.96 0.490 0.041 12 12/26/74 23:00 0.028 27 1.89 0.470 ' 0.026 30 12/03/75 17:00 0.028 28 1.82 0.450 0.003 50 3/24/77 20:00 0.026 29 1.75 0.430 0.022 37 12/10/77 17:00 0.026 30 1.70 0.410 ' 0.013 46 2/12/79 7:00 0.025 31 1.64 0.390 0.036 16 12/15/79 8:00 0.024 32 1.59 0.370 0.020 40 12/26/80 3:00 0.024 33 1.54 0.350 0.036 17 10/06/81 15:00 0.023 34 1.49 0.330 0.035 19 1/05/83 8:00 0.023 35 1.45 0.310 0.023 35 1/24/84 11:00 0.022 36 1.41 0.291 0.011 48 2/11/85 5:00 0.022 37 1.37 0.271 Computed 0.060 6 1/18/86 21:00 0.021 38 1.33 0.251 ' 0.048 9 11/24/86 4:00 0.020 39 1.30 0.231 0.018 43 1/14/88 12:00 0.020 40 1.27 0.211 0.012 0.082 47 1 4/05/89 1/09/90 16:00 9:00 0.019 0.019 41 42 1.24 1.21 0.191 0.171 0.072 4 4/05/91 2:00 0.018 43 1.18 0.151 0.024 33 1/27/92 17:00 0.017 44 1.15 0.131 0.025 31 3/23/93 0:00 0.014 45 1.12 0.111 0.007 49 3/03/94 3:00 0.013 46 1.10 0.091 0.037 15 2/19/95 20:00 0.012 47 1.08 0.071 0.073 3 2/09/96 1:00 0.011 48 1.05 0.051 ' 0.040 14 1/02/97 9:00 0.007 49 1.03 0.031 0.014 45 1/07/98 9:00 0.003 50 1.01 0.011 Computed Peaks 0.097 100.00 0.990 Computed Computed Peaks Peaks 0.085 0.074 50.00 25.00 0.980 0.960 ,Computed Peaks PRE DEVELOPED 0-058 10.00 0.900 Computed Peaks (FORESTED 0.065 8.00 0.875 Computed Peaks CONDITION) 100 -YEAR 0.046 5.00 0.800 Computed Peaks WEAK STORM EVENT 0.030 2.00 0.500 Computed Peaks 0.020 1.30 0.231 Flow -Frequency- Analysis T----TLogPearson-III -Coefficients 0.177 46 1/13/73 2:00 0.222 25 2.04 0.510 0.212 30 11/28/73 9:00 0.221 26 1.96 0.490 0.278 10 12/26/74 23:00 0.220 27 1.89 0.470 0.181 Time Series File:rnfs dev110119_tsf Mean= -0.637 StdDev= 0.107 0.213 Project Location:Sea-TacSkew= 1.82 0.450 0.450 28 8/26/77 2:00 --Annual Peak Flow Rates--- -T -Flow Frequency Analysis ------- 9/17/78 Flow Rate Rank Time of Peak - - Peaks - - Rank Return Prob ' (CFS) 0.236 21 2/16/49 21:00 (CFS) 0.412 1 Period 89.50 0.989 0.177 0.387 2 3/03/50 16:00 0.387 2 32.13 0.969 47 0.240 20 2/09/51 2:00 0.378 3 19.56 0,949 1.05 0.190 41 10/15/61 13:00 0.376 4 14.08 0.929 ' 0.181 44 3/24/53 15:00 0.330 5 10.99 0.909 0.220 27 12/19/53 19:00 0.330 6 9.01 0.889 'Computed 0.228 0.222 23 24 11/25/54 11/18/55 2:00 15:00 0.302 0.294 7 8 7.64 6.63 0.869 0.849 Peaks 0.262 15 12/09/56 14:00 0.292 9 5.86 0.829 CONDITIONS I(UNMITIGATED) 0.232 22 12/25/57 16:00 0.278 10 5.24 0.809 0.310 0.172 47 11/18/58 13:00 0.271 11 4.75 0.789 ' 0.222 2S 11/20/S9 5:00 0.270 12 4.34 0.769 0,197 36 2/14/61 21:00 0.269 13 3.99 0.749 0.196 0.196 38 37 11/22/61 12/15/62 2:00 2:00 0.267 0.262 14 15 3.70 3.44 0.729 0.709 0,221 26 12/31/63 23:00 0.258 16 3.22 0.690 0.196 35 12/21/64 4:00 0.257 17 3.03 0.670 0.199 34 1/05/66 16:00 0.254 18 2.85 0.650 ' 0.302 7 11/13/66 19:00 0.248 19 2.70 0.630 0.330 5 8/24/68 16:00 0.240 20 2.56 0.610 0.182 0.201 43 33 12/03/68 1/13/70 16:00 22:00 0.236 0.232 21 22 2.44 2.32 0.590 0.570 0.191 40 12/06/70 8:00 0.228 23 2.22 0.550 0.294 8 2/27/72 7:00 0.222 24 2.13 0.530 0.177 46 1/13/73 2:00 0.222 25 2.04 0.510 0.212 30 11/28/73 9:00 0.221 26 1.96 0.490 0.278 10 12/26/74 23:00 0.220 27 1.89 0.470 0.181 45 12/02/75 26:00 0.213 28 1.82 0.450 0.213 28 8/26/77 2:00 0.213 29 1.75 0.430 0.292 9 9/17/78 2:00 0.212 30 1.70 0.410 0.258 16 9/08/79 15:00 0.208 31 1.64 0.390 ' 0.257 17 12/14/79 21:00 0.207 32 1.59 0,370 0.271 11 11/21/80 11:00 0.201 33 1.54 0.350 0.376 4 10/06/81 0:00 0.199 34 1.49 0.330 0,269 13 10/28/82 16:00 0.198 35 1.45 0.310 0.213 29 1/03/84 1:00 0.197 36 1.41 0.291 0.184 42 6/06/85 22:00 0.196 37 1.37 0.271 0.254 18 1/18/86 16:00 0.196 38 1,33 0.251 0.330 6 10/26/86 0:00 0.191 39 1.30 0.231 0.148 49 11/11/87 0:00 0.191 40 1.27 0.211 0.191 39 8/21/89 17:00 0.190 41 1,24 0.191 ' :Computed Peaks 100 -YEAR PEAK 0. 2 8 2 5.00 0,890 Computed Peaks STORM EVENT 0.226 2.00 0.500 Computed Peaks 0.190 1.30 0.231 0.412 1 1/09/90 6:00 0.184 42 1.21 0.171 0.378 3 11/24/90 8:00 0.182 43 1.18 0.151 0.207 32 1/27/92 15:00 0.181 44 1.15 0.131 0.138 50 11/01/92 15:00 0.181 45 1.12 0.111 ' 0.159 48 11/30/93 22:00 0.177 46 1.10 0,091 0.208 31 11/30/94 4:00 0.172 47 1.08 0,071 0.267 14 2/08/96 10:00 0.159 48 1.05 0.051 0.248 19 1/02/97 6:00 0.148 49 1.03 0.031 0.270 12 10/04/97 15:00 0.138 50 1.01 0.011 :Computed Peaks 0.444 100.00 0.990 'Computed Peaks 0.406 50.00 0.980 ' .Computed Peaks DEVELOPED SITE 0.368 25.00 0.960 Computed Peaks CONDITIONS I(UNMITIGATED) 0.320 10.00 0.900 ,Computed Peaks 0.310 8.00 U-875 ' :Computed Peaks 100 -YEAR PEAK 0. 2 8 2 5.00 0,890 Computed Peaks STORM EVENT 0.226 2.00 0.500 Computed Peaks 0.190 1.30 0.231 ',ComputingDurations: Flow Frequency Analysis LogPearson IIT Coefficients Mean= Time Series File:rdout.tsf ' Project Locati.on:Sea-Tac ------Flow Frequency ---Annual Peak Flow Rates— - - Peaks - - Flow Rate Rank Time of Peak (CFS) (CFS) Period 0.083 0.014 39 2/22/49 22:00 0,062 0.033 17 1/22/50 6:00 0.058 0.083 1 2/09/51 20:00 ' 0.013 44 2/04/52 7:00 0.057 0.030 18 1/31/53 11:00 0.055 0.015 33 1/07/54 21:00 0.054 0.014 37 2/08/55 12:00 0.054 0.049 10 1/06/56 10:00 0.050 0.014 35 2/26/57 11:00 0.049 0.015 25 1/17/58 10:00 ' 0.014 36 1/27/59 1:00 0.042 0.054 7 11/21/59 3:00 0.039 0.038 14 11/24/60 11:00 ' 0.013 46 12/24/61 6:00 0.037 0.016 24 11/30/62 19:00 0.036 0.036 16 11/19/63 16:00 0.033 0.039 13 12/01/64 2:00 ' 0.015 29 1/07/66 4:00 0.030 0.030 19 12/15/56 8:00 0.026 0.015 32 1/20/68 21:00 0.021 0.015 31 12/11/69 10:00 0.019 0.017 23 1/27/70 5:00 0.017 0.015 30 12/07/70 12:00 0.016 0.057 4 3/06/72 22:00 ' 0.042 12 12/26/72 6:00 0.015 0.015 26 1/18/74 20:00 0.015 0.014 38 1/14/75 0:00 ' 0.014 34 12/04/75 5:00 0.015 0.012 48 8/26/77 7:00 0.015 0.021 21 12/15/77 19:00 0.015 0.012 49 2/12/79 18:00 0.015 0.055 6 12/17/79 20:00 0.015 0.015 28 12/30/80 22:00 0.014 0.047 11 10/06/81 18:00 ' 0.015 27 1/08/83 6:00 0.014 0.013 45 12/10/83 19:00 0.014 0.013 41 11/04/64 8:00 0.014 0.019 22 1/19/86 7:00 ' 0.050 9 11/24/86 8:00 0.014 0.014 40 12/10/87 8:00 0.013 0.013 43 11/05/88 22:00 0.013 0.057 5 1/09/90 15:00 0.013 0,058 3 1.1/24/90 16:00 0.013 0,026 20 1/31/92 23:00 0.013 0.012 47 1/26/93 5:00 0.013 0.011 50 2/17/94 22:00 0.012 0.037 15 12/27/94 7:00 0.012 0.062 2 2/09/96 4:00 0.012 0.054 8 1/02/97 12:00 0.011 0.013 42 1/25/98 0:00 p 0.120 Computed Peaks 100.00 0.990 0.094 iComputed Peaks 50.00 ' 'Computed Peaks DEVELOPED SITE oo 0.960 ;Computed Peaks CONDITIONS 10.00 0.900 Computed Peaks (MITIGATED) 8.00 ' Computed Peaks 100 -YEAR PEAK STORM EVENT 5.00 Computed Peaks 3.05 2.00 Computed Peaks 2.55 Mean= -1.648 StdDee= 0.264 Skew= 0.608 ------Flow Frequency Analysis--- - - Peaks - - Rank Return Prob (CFS) (€t) Period 0.083 4.01 1 89.50 0.989 0,062 3.89 2 32.13 0.969 0.058 3.73 3 19.58 0.949 0.057 3.72 4 14.08 0.929 0.057 3.71 5 10.99 0.909 0.055 3.64 6 9.01 0.889 0.054 3.62 7 7.64 0.869 0.054 3.61 8 6.63 0.849 0.050 3.50 9 5.86 0.829 0.049 3.46 10 5.24 0.809 0.047 3.40 11 4.75 0.789 0.042 3.30 12 4.34 0.769 0.039 3.23 13 3.99 0.749 0.038 3.22 14 3.70 0.729 0.037 3.20 15 3.44 0.709 0.036 3.18 16 3.22 0.690 0.033 3.14 17 3.03 0.670 0.030 3.10 18 2.85 0.650 0.030 3.09 19 2.70 0.630 0.026 3.07 20 2.56 0.610 0.021 3.05 21 2.44 0.590 0.019 3.04 22 2.32 0.570 0.017 3.02 23 2.22 0.550 0.016 2.92 24 2.13 0.530 0.015 2.89 25 2.04 0.510 0.015 2,83 26 1.96 0.490 0.015 2.80 27 1.89 0.470 0.015 2.77 28 1.82 0.450 0.015 2.76 29 1.75 0.430 0.015 2.76 30 1.70 0.410 0.015 2.65 31 1.64 0.390 0.015 2.64 32 1.59 0.370 0.015 2.60 33 1.54 0.350 0.014 2.60 34 1.49 0.330 0.014 2.51 35 1.4S 0.310 0.014 2.38 36 1.41 0,291 0.014 2.38 37 1.37 0.271 0.014 2.32 38 1.33 0.251 0.014 2.31 39 1.30 0.231 0.014 2.30 40 1.27 0.211 0.013 2.08 41 1.24 0.191 0.013 2.04 42 1.21 0.171 0.013 2.01 43 1.18 0,151 0.013 1.95 44 1.15 0.131 0.013 1.93 45 1.12 0.111 0.013 1.92 46 1.10 0.091 0.012 1.83 47 1.08 0.071 0.012 1.68 48 1.05 0.051 0.012 1.63 49 1.03 0.031 0.011 1.53 50 1.01 0.011 p 0.120 4.02 100.00 0.990 0.094 4.01 50.00 0.980 0.073 4.00 25.00 0.960 0.050 3.52 10.00 0.900 0.047 3.40 8.00 0.875 0.037 3.19 5.00 0.800 0.021 3.05 2.00 0.500 0.014 2.55 1.30 0.231 Firestone Technical Information Report Renton, Washington Appendix D — Detention Calculations PACLAND Project #10.113.001 Page 4 I Retention/Detention Facility Type of Facility: Detention Pond Side Slope: 2,00 H:1V Pond Bottom Length: 120.00 ft Pond Bottom Width: 24.20 ft Pond Bottom Area: 2904. sq. ft Top Area at 1 ft. FB: 6188. sq. £t 0.142 acres Effective Storage Depth: 4.00 It Stage 0 Elevation: 397.50 ft Storage Volume: 16572, cu. ft 0.380 ac -ft Riser Head: 4.00 ft Riser Diameter: 12.00 inches Number of orifices: 2 Full Head Pipe Orifice # Height Diameter Discharge Diameter (ft) (in) (CFS) (in) 1 0.00 0.58 0,018 2 3.00 1.31 0.047 4.0 Top Notch Weir: None Outflow Rating Curve: None Stage Elevation Storage Discharge Percolation Surf Area (ft) (ft) (cu. ft) (ac -ft) (cfs) (cfs) (sq. ft) 0.00 397.50 0. 0.000 0.000 0.00 2904. 0.01 397.51 29. 0.001 0.001 0.00 2910- 0.02 397.52 58. 0.001 0.001 0.00 2916. 0.03 397.53 87. 0.002 0.002 0.00 2921. 0.04 397.54 117. 0.003 0.002 0.00 292`1. 0.05 397.55 146. 0.003 0.002 0.00 2933. 0.1.5 397.65 442. 0.010 0.003 0.00 2991- 0.25 397.75 744. 0.017 4.005 0.00 3049. 0.35 397.85 1052. 0.024 0.005 0.00 3108. 0.45 397.95 1366. 0.031 0.006 0.00 3167. 0.55 398.05 1685. 0.039 0.007 0.00 3226. 0.65 398.15 2013.. 0.046 0.007 0.00 3286. 0.75 398.25 2343. 0.054 0.008 0.00 3346. ' 0.85 398.35 2680. 0.062 0.008 0.00 3406. 0.95 398.45 3024. 0.069 0.009 0.00 3466. 1.05 398.55 3373. 0.077 0.009 0.00 3527. 1_15 1.25 398.65 398.75 3729. 4091, 0.086 0.094 0.010 0.010 0.00 0.00 3588. 3650. 1.35 398.85 4459. 0.102 0.011 0.00 3`112. 1.45 398.95 4833. 0.111 0.011 0.00 3179. 1.55 399.05 5214. 0.120 0.011 0.00 3836. 1.65 399.15 5601. 0.129 0.012 0.00 3899. 1.75 399.25 5994. 0.138 0.012 0.00 3962. 1.85 399.35 6393, 0.1.47 0.012. 0.00 4025. 1.95 399.4.5 6799. 0.156 0.013 0.00 4090- 2.05 399.55 ?211. 0.166 0.013 0.00 4154. 2.15 399.65 '1630. 0.175 0.013 0.00 4218. 2.25 399.75 8055. 0.185 0.014 0.00 428x. i 2.35 399.85 8486. 0.195 0.014 0.00 4348. 2.45 399.95 8924. 0.205 0.014 0.00 4413. 2.55 400.05 9369_ 0.215 0.014 0.00 4479. 2.65 400.15 9820. 0.225 0.015 0.00 4545. 2.75 2.85 400.25 400.35 10278. 10742. 0.236 0.247 0.015 0.015 0.00 0.00 4611. 4678. 2.95 400.45 11214. 0.257 0.016 0.00 4745. 3.00 400.50 11452. 0.263 0.016 0.00 4778. 3.01 400.51 11499. 0.264 0.016 0.00 4785. 3.03 400.53 11595. 0.266 0.017 0.00 4799. 3.04 400.54 11643. 0.267 0.019 0.00 4805, 3.05 400.55 11691, 0.268 0.021 0.00 4812, 3.07 400.57 11788. 0.271 0.025 0.00 4826. 3.08 400.58 11836. 0.272 0.029 0.00 4832, 3.10 400.60 11933. 0.274 0.030 0.00 4846. 3.11 400.61 11981. 0.275 0.031 0.00 4853. 3.21 400.71 12470, 0.286 0.038 0.00 4920. 3.31 400.81 12965. 0.298 0.042 0.00 4989. 3.41 400.91 13468. 0.309 0.047 0.00 5057. 3.51 401.01 13977. 0.321 0.050 0.00 5126- 3.61 401.11 14493. 0.333 0.054 0.00 5195. 3.71 401.21 15016. 0.345 0.057 0.00 5264. 3.81 401.31 15546. 0.357 0.060 0.00 5334. 3.91 401.41 16083. 0.369 0.063 0.00 5404. 4.00 401.50 16572. 0.380 0.065 0.00 546"1. 4.10 401.60 17122. 0.393 0.375 0.00 5538- 4.20 401.70 17679. 0.406 0.941 0.00 5609. 4.30 401.80 18244. 0.419 1.670 0.00 5680. 4.40 401.90 18815. 0.432 2.470 0.00 5752.. 4.50 402.00 19394. 0.445 2.750 O.D0 5824. 4.60 402.10 19980. 0.459 3.010 0.00 5896. 4.70 402.20 20573. 0.472 3.240 0.00 5968. 4.80 402.30 21174. 0.486 3.470 0.00 6041. 4.90 402.40 21'782. 0.500 3.670 0.00 6114, 5.00 402.50 22397. 0.514 3.870 0.00 6188. 5.10 402.60 23019_ 0.528 4.050 0.00 6262. 5.20 402.70 23649, 0.543 4.2.30 0.00 6336. 5.30 402.80 24286. 0.558 4.400 0.00 6410. 5.40 402.90 24931. 0.572 4.570 0.00 6485. 5.50 403.00 25583. 0.587 4.730 0.00 6560. 5.60 403.10 26243, 0.602 4.880 0.00 6636. 5.70 903.20 26911, 0.618 5.030 0.00 6712. 5.80 403.30 27586. 0.633 5.170 0.00 6788. 5.90 403.40 28268. 0.649 5.310 0.00 6864. 6.00 403.50 28958. 0.665 5.450 0.00 6941. Hyd Inflow Outflow Weak Storage Target Calc Stage Elev (Cu -Ft) (Ac--F") 1 0.41 0.10 0.06 3.71 401.21 15032. 0.345 2 0.24 ******* 0.06 3.89 401.39 15997, 0.367 3 0.21 ******* 0.06 3.83 401.33 15656. 0.359 4 0.38 ******" 0.06 3.73 401.23 15098. 0.347 5 0.38 ******* 0.04 .3.24 400.74 12624, 0.290 6 0.26 ******* 0.05 3.64 401.14 19631. 0.336 7 0.1-7 ******' 0.03 3.07 400.57 11801, 0.271 8 C.14 ******* 0.01 2.30 3°O.SC 8274. 0.190 1 t i t r] 1 t ---------------------------------- Route Time Series through Facility inflow Time Series File:rnfsdev110119.tsf Outflow Time Series File:rdout Inflow/Outflow Analysis Peak Inflow Discharge: 0.412 CFS at 6:00 on Jan 9 in 1990 Peak Outflow Discharge: 0.083 CES at 20:00 on Feb 9 in 1951 Peak Reservoir Stage: 4.01 Ft Peak Reservoir Elev: 401.51 Ft Peak Reservoir Storage: 16604. Cu -Ft 0.381 Ac -Ft Flow Duration from Time Series File:rdout.tsf Cutoff Count Frequency CDF Exceedence_Probability CFS % % 0.001 206794 47.213 47.213 52.787 0.528E+00 0.003 61754 14.099 61.312 38.688 0.387E+00 0.006 48753 11.131 72.443 27.557 0.276E+00 0.008 47990 10.957 83.400 16.600 0.166E+00 0.010 29430 6.719 90.119 9.881 0.988E--01 0.013 24712 5.642 95.761 4.239 0.424E--01 0.015 15593 3.560 99.321 0.679 0.679E-02 0.01'7 1694 0.387 99.708 0.292 0.292E-02 0.020 123 0.028 99.736 0.264 0.264E-02 0.022 101 0.023 99.759 0.241 0.241E-02 O.024 99 0.023 99.782 0.218 0.27.8E-02 0.027 56 0.013 99.794 0.206 0.206E-02 0.029 39 0.009 99.803 0.19`1 0.19"7E-02 0.031 140 0.032 99.835 0.165 0.165E-02 0.033 97 0.022 99.857 0.143 0.143E-02 0.036 81 0.018 99.876 0.124 0.124E-02 0.038 82 0.019 99.895 0.105 0.105E-02 0.040 89 0.020 99.915 0.085 0.852E-03 0.043 60 0.014 99.929 0.071 0.715E--03 0.045 49 0.011 99.940 0.060 0.603E--03 0.047 44 0.010 99.950 0.050 0.502E-03 0.050 67 0.015 99.965 0.035 0.349E--03 0.052 28 0.006 99.971 0.029 0.2858-03 6.654 37 0.008 99.980 0.020 0.201E-03 0.057 39 0.009 99.989 0.011 0.112E-03 0.059 25 4.006 99.995 0.005 0.548E-04 0.061 8 0.002 99.996 0.004 0.365E-04 0.064 10 0.002 99.999 0.001 0.137E--04 0.066 5 0.001 100.000 0.000 0.228E-05 0.068 G 0.000 lcc.c00 0.004 0.228E-05 0.070 0 0.000 100.000 0.000 0.228E-05 0.073 0 0.000 100.000 0.000 0.228E-05 0.0`75 0 0.000 100.400 0.000 0.228E-05 0.077 0 0.000 100.000 0.000 0.228E-05 0.680 0 0.000 100.000 0.000 0.228E'.--05 0.082 0 0.000 100.000 0.000 C.228E-05 Duration Comparison Anaylsis Base File: rrifs_predev.tsf New File: rdout.tsf Cutoff Units: Discharge in CFS i t .1 1 LI E t 1 Fraction of Time ----- Cutoff Base New Base %Change 0.015 1 0.99E-02 0.015 0.12E-01 0.3 20.4 0.021 1 0.44E-02 -24.9 0.25E-02 0.028 -44.0 0.028 1 0.22E-02 0.034 0.20E-02 4.8 -9.3 0.034 1 0.13E-02 7.5 0.14E-02 0.047 11.3 0.040 0.69E-03 0.053 0.87E--03 -1.1 26.1 0.047 1 0.43E-03 -6.8 0.54E-03 0.065 26.7 0.053 1 0.28E-03 0.072 0.26E-03 -13.6 -6.6 0,059 1 0.16E-03 -16.8 0.53E-04 -66.2 0.065 1 0.66E-04 0.23E-05 -96.6 0.072 1 0.30E-04 0.23E-05 -92.3 0.078 1 0,46E-05 0,23E-05 -50.0 ---------Check of Tolerance Probability Base New %Change 0.99E-02 0.015 0.015 0.3 0.44E-02 0.021 0.016 -24.9 0.22E-02 0.028 0.024 -13.9 0.13E-02 0.034 0.036 4.8 0.69E-03 0.040 0.043 7.5 0.43E-03 0.047 0.048 3.7 0.28E-03 0.053 0.052 -1.1 0.16E-03 0.059 0.055 -6.8 0.66E-04 0.065 0.058 -11.3 0.30E-04 0.072 0.062 -13.6 0.46E-05 0.078 0.065 -16.8 Maximum positive excursion � 0.004 cfs ( 8.7%) occurring at 0.042 cfs on the Base Data:rnfs_predev.tsf and at 0.046 cfs on the New Data:rdout.tsf Maximum negative excursion = 0.008 cfs (-32.3%) occurring at 0.025 cfs on the Base Data:rnfs_predev.tsf and at 0.017 cfs on the New Data:rdout.tsf t i n t 1 f Firestone 1 1 Technical Information Report Renton, Washington Appendix E -- Water Quality Calculations IPACLAND Project #10-113-001 Page 5 } .PACLAND.COM � I � I � I if 11 11 'L It 1-7- oil PROJECT: ME (} DESCRIPTION: BASIC, VJF POND p.4-1 0.0 SIR' r = (0.9 k 44.7S Ott) x( -P,) Ac: ZG,I14 sS Ay 4 % 3"12 ,S� vf= �(0,�}(2y 911 + (0,2�,g, ��z x (0.039 Vr = I � z� u5: (3)(1(2-( J) Vu1 0,,-,-79 r -f r L r r �I I u _J r oke_' I 1/_.hjT! 0IhAj6 It ■..1to_.. CONSTRUCTION PRODUCTS INC. Prepared by Kathryn Thomason on January 37, 2011 Size and Cost Estimate Firestone - Stormwater Treatment System Renton, WA Information provided: • Total contributing area = 1.04 acres • Impervious area = 0.62 acres • Water quality flow, Qq = 0.103 cfs • Peak hydraulic flow rate, Qp.ak = 0.943 cfs • Presiding agency = City of Renton, WA Assumptions: • Media = CSF cartridges • Cartridge Height = Low -drop • Cartridge flow rate= 10 gprin • Drop required from inlet to outlet = 1.8' minimum Size and cost estimates: The StormFilter is a flow -based system, and is therefore sized by calculating the peak ater quality flow rate associated with the design storm. The water quality flow rate was calculated using 35% of he developed 2-ye3r peak flow from KCRTS. for the purposes of developing this estimate. The StormFilter for this site was sized based on a water quality flow rate of 0.103 cfs. To mmodate this flow rate, CONTECH Construction Products Inc. recommends using a 72" Manhole StormFilter ith 5 cartridges (see attached detail). The estimated cost of this system is$19.800, complete and delivered to the ob site. This estimate assumes that the manhole is 6 feet deep. The final system cost will depend on the actual epth of the units and whether extras are specified. The contractor is responsible for setting the StormFilter and all a emal plumbing. Typically the precast StormFilters have internal bypass capacities of 1.8 cfs. If the peak d scharge off the site is expected to exceed this rate, we recommend placing a high-flow bypass upstream of the StormFilter system. CONTECH Construction Products could provide our high-flow bypass, the StormGate, which Orovides a combination weir -orifice control structure to limit the flow to the StormFilter. The estimated cost of this s ucture is $4,000. The final cost would depend on the actual depth and size of the unit. @2008 CONTECH Construction Products Inc. 11835 NE Glenn widing Dr., Portland OR 97220 www contech-cpi cpm Toll-free: 800.548.4667 Fax: 800.561.1271 Page 1 of 1 TS -P027 Firestone Technical Information Report Renton, Washington Appendix F — Infiltration Feasibility Study PACLAND Project #10.113.001 Page 6 1 1 t 1 1 1 OTTO ROSENAU & ASSOCIATES, INC. Geotechnical Engineering, Construction Inspection & Materials Testing - - 6747 M. L. King Way South, Seattle, Washington 98118-3216 USA Tel: (206) 725-4600 • Tall Free: (888) OTTO-4-US • Fax: (206) 723-2221 January 17, 2011 WBE W2F5913684 • WABO Registered Agency • website: www.ottorosenau.com FES Group 772 30th Ave N St. Petersburg FL 33704 RE: Infiltration Feasibility Study Proposed Firestone Complete Auto Care Facility 421 Union Avenue Northeast Renton, Washington ORA Project Number: 10-0708 INTRODUCTION We understand that a new Firestone Complete Auto Care Facility is planned at 421 Union Avenue Northeast in Renton, Washington. Please see the attached Vicinity Map on page A-1 of the appendix for an approximate location of the project site. An infiltration pond is being considered to dissipate stormwater collected from future impervious surfaces at the project site into the underlying subgrade soil. The City of Renton requires that the design of infiltration facilities be completed in accordance with the guidelines specified in the King County Surface Water Design Manual. As a result, as series of 4 test pits were completed at the proposed infiltration pond. Falling head percolation tests were performed at three of these locations_ SUBSURFACE CONDITIONS Four test pits (TP -1 through TP -4) were completed at the northeast corner of the project site at the proposed location of the infiltration pond on January 6, 2011. Please see the attached Site Plan on page A-2 for approximate locations of the test pits. Stockpiles of uncontrolled fill was present at the ground surface at each test pit location. The stockpiles contained a mix of soil, wood, concrete rubble and metal debris. The stockpiles were pushed to the side prior to beginning each test pit using the subcontracted excavator. Test pits TP -1, TP -3, and TP -4 were completed to a depths of about 7 to 8 feet below the existing adjacent site grade. Test pit TP -2 was completed to a depth of about 13 feet below the existing adjacent site grade. Similar subsurface conditions were observed in test pits TP -1 through TP -3 with approximately 1 to 6 feet of loose to medium dense, light brown silty sand fill at the ground surface. The light brown silty sand with gravel fill was underlain 1.6 to 3.6 feet of with medium dense, orange - brown silty sand with gravel that we interpreted to be native, weathered till. The weathered till was underlain with dense to very dense silty sand with gravel that we interpreted to be glacial till. At TP -4 we observed the weathered glacial till immediately after the stockpiled fill soils were pushed aside. The soil at the base of each test pit consisted of dense to very dense, gray 1 fl 1 1 t 1 Firestone Renton January 17, 2011 glacial till. Please see the attached test pit logs on pages A-3 through A-6 of the appendix for a full description of the observed subsurface soil and groundwater condtions_ Slight to moderate groundwater seepage was observed in test pit TP -2 between depths of 10.5 and 13 feet below the existing adjacent site grade. We anticipate that the seasonal high groundwater level at this location is at approximately 10.5 feet below the existing adjacent site grade, which corresponds to about Elevation 397.5 feet as shown on the preliminary grading plan. INFILTRATION TESTS An infiltration test was completed at the test pits TP -1, TP -3 and TP4 using the Falling Head Percolation test procedure. A single, 6 -inch diameter PVC pipe was placed in the completed test pit excavations. The soil around the pipes was carefully backfilled. The pipe was seated into the ground by soundly tapping a block of wood at the top of the pipe with a 3 -pound hammer. 2 inches of clean gravel was placed at the base of each stand pipe. The following morning (11712011) the soil at the base of each pipe was soaked for 4 hours by maintaining at least 12 inches of clean water in the pipe. The following morning (11812011), approximately 20 hours after the soaking period was completed, the percolation tests were performed. The percolation tests were performed. The measured infiltration rates are presented in the following table. Please see the details of each percolation test in the logs on pages A-8 through A-10 of the appendix. The measured infiltration rate must be modified in accordance with the requirements of the King County Surface Water manual in accordance with the following formula to come up with the design infiltration rate. !design — 1 measured X Ffesting X Fgeomefry X Fpiugging Otto Rosenau & Associates, Inc. Page 2 of 3 1 Measured Infiltration Test Pit/infiltration Test Rate - Imeasured Location (minutes per inch) Notes TP -1 12.3 Assumed to have a poor seal at base of pipe and not representative TP -3 48 Assumed to have a poor seal at base of pipe and not representative TP -4 240 Appeared to have a good seal at the base of the pipe and is representative Please see the details of each percolation test in the logs on pages A-8 through A-10 of the appendix. The measured infiltration rate must be modified in accordance with the requirements of the King County Surface Water manual in accordance with the following formula to come up with the design infiltration rate. !design — 1 measured X Ffesting X Fgeomefry X Fpiugging Otto Rosenau & Associates, Inc. Page 2 of 3 1 IFirestone Renton January 17, 2011 We recommend that the measured infiltration rate (I11,easumd) be 240 minutes per inch, or 0.0042 inches per minute. The geometry factor (F9eo,,,etry) is must be between 0.25 and 1 as determined by the formula L f {4 x { = DI W)} +0.05 $e01ne1�,, Where D = depth from the bottom of the proposed facility to the maximum wet -season water table or nearest impervious layer, whichever is less W = width of the facility t 1 L L 1 1 r t For a 100 -foot wide pond built over a shallow water table with a depth of 5 feet below the facility, Fgeo"4 _ {4 x (51100)1 +0.05 = 0.25. The current design bottom of infiltration facility would likely need to be revised to a higher elevation to provide greater separation between the design bottom of pond and the maximum wet season water table at about Elevation 397.5 feet. This also roughly coincides with the depth to the dense to very dense tills at the site. We recommend that Fviusg;ns be equal to 0.8 (for fine sands and loamy sands). A value of 0.3 is to be used for Ftestin9 when the EPA falling head percolation rate is used to measure infiltration rates in the field. As a result, if a F9e=etry of 0.25 is assumed the design infiltration rate is Idesign = (0.0042 inches/minute) x 0.3 x 0.25 x 0.8 = 0.00025 inches 1 minute. We anticipate that this would render the current design to be unfeasible due to the very large size of the infiltration pond that would be required. An infiltration pond may not be possible at this site due to the relatively shallow depth to groundwater and relatively impervious soils. At a minimum, a revised infiltration facility would need to have its base at a shallower depth to increase the separation between the groundwater and relatively impervious soils. This may be able to be accomplished by using an open -bottomed, arched vault system that can be built beneath paved areas. Alternatively, a detention tank and a connection to the public sewer system may be required. If you have any questions, please contact us. Sincerely, OTTO ROSENAU &A SSOCIA TES, INC. Anthony Coyne, P. Geotechnical Engineer Otto Rosenau & Associates, Inc. Page 3 of 3 1 9L 1 1 11 l F� i L.1 APPENDIX 1 •. bndSPr II � / i j LU a t. 122 Note: The location of all features shown is approximate. Scale: Not to scale Reference: USGS Quad - Renton, WA - MAPTECH MAPS: Washington. VICINITY MAP Project Name: Firestone Renton i For: FES Group Location: 421 Union Avenue NE, OTTO ROSENAU & Renton, WA ASSOCIATES, INC. SRA Project Number: 10-0708 Date: January 11, 2011 A-1 C3 N 11 L L3 c m U) 3.y� 4Q H ' -.aa-��„75�?7��XYMY..'FY. i •"�'S ^"'A"'i`�'�,r' :�. v , W.x. _ .-. i'x'i" :.�,,..1� � 3N 3nN3AV NOINn mm¢p�g a�---NIT R 3.y� 4Q H ' -.aa-��„75�?7��XYMY..'FY. i •"�'S ^"'A"'i`�'�,r' :�. v , W.x. _ .-. i'x'i" :.�,,..1� � ;.t 3 i; i❑ fl M a p i I z z i S tot- { w re � tot- - I W �r�,\\ xaI� .,.� �. 111 IP� � i S o c �� , \ p l ro LLJ U Lj N S") (0 O �; 3 0Oa 9 n C Ul 4. v m o- i8 I a4 v m ] Mcm n r I �x=o a p a N N 0o Iia I �u 5 L m Z D Qy ttf N - - ...,. .. m is - N Ch Q � C m O O `5 O - nw o Z W I— fY p Q Z L� 1 1 OTTO ROSENAU & ASSOCIATES, INC. TEST PIT NUMBER TP -1 6747 M.L. King Way South Seattle, WA 98118 PAGE 1 OF 1 Telephone: (206) 725-4600 Fac (206) 723-2221 CLIENT FES Group PROJECT NAME Firestone Renton PROJECT NUMBER 10-0708 PROJECT LOCATION 421 Union Avenue Northeast, Renton, Washinqton DATE STARTED 116111 COMPLETED 116111 GROUND ELEVATION 408 ft TEST PIT SIZE 4' w x 10' I x 8' d EXCAVATION CONTRACTOR Evergreen On -Site GROUND WATER LEVELS: EXCAVATION METHOD Steel -crack excavator AT TIME OF EXCAVATION Not encountered LOGGED BY Jeff Rabe CHECKED BY Anthony Coyne P.E. AT END OF EXCAVATION Not encountered NOTES Infiltration test. Approx. 2' yard waste old fill and rubble removed AFTER EXCAVATION Not observed }W F- W S W g Q q MATERIAL DESCRIPTION IL D Qz 0.0 SM Loose to medium dense, light brown, silly SAND with gravel (Fill) (moist) 2.5 GB 1 4,5 403.5 5.0 SM :-, Loose to medium dense, gray, silty SAND with gravel (Fill) (moist) (old topsoil horizon at depth of about 6 feet) :• 6.a 402.0 GB 2 SM Medium dense, orange -brown, silty SAND with gravel (Native) (mast) (weathered glacial till) 7.5 7.5 400.5 GB �_. 3 SM ` 6.0Very dense, gray, silly SAND with gravel (moist) (glacial till) 400.0 13ottom of test pit at 8.0 feel. i i i i i i i i i i i 7 A-3 1 I IL 11 1 P; 1� OTCQ RQSENAtJ 8 ASSOCIATES, INC.TEST PIT NUMBER TP -2 6747 M, L. !ting Way South PAGE 1 OF 1 Seattle, WA 98118 Telephone: (206) 725-46DO Fax: (206) 723-2221 CLIENT FES Group PROJECT NAME Firestone Renton PROJECT NUMBER 10-0708 PROJECT LOCATION 421 Union Avenue Northeast, Renton, Washington DATE STARTED 116111 COMPLETED 116111 GROUND ELEVATION 408 ft TEST PIT SIZE 6' w x 12' I x 13' d EXCAVATION CONTRACTOR Ever een On-site GROUND WATER LEVELS: EXCAVATION METHOD Steel -track excavator �-Z AT TIME OF EXCAVATION 10.5 It / Bev 397.5 ft LOGGED BY Jeff Rabe CHECKED BY Anthony Coyne P_E. TAT END OF EXCAVATION i2.0 fI ! Elev 396.0 ft NOTES No Infiltration test. ApprOx Z yard waste, old fill, rubble removed Q 2hrs AFTER EXCAVATION 11.5 0 t Bev 396.5 ft W a� C w CO w[L r D MATERIAL DESCRIPTION � a� ¢z 0.4 SM :: Loose to medium dense, light brown, silty SAND with gravel (Fill) (moist) 2.5 4.0 404.0 5.0 GB 1 SM ,, Medium dense, orange -brown, silly SAND with gravel (Native) (moist) (weathered glacial till) 7.5 ': 7.5 400.5 Grades to dense, gray, glacial 611 s 10.0 Slight groundwater seepage observed at depth of 10 feet GB 2 Q i SM .: Very dense, gray silty SAND with gravel (wet) (glacial till) GB i 3 Z 12.5 '- GB 4 13.0 395.0 _ Bottom of test pit at 13.0 feet. C i A-4 1 1 Ll 1 1 0170 ROSENAU & ASSOCIATES, INC. TEST PIT NUMBER TP -3 6747 M.L.. King Way South Seattle, WA 98118 PAGE 1 OF 1 Telephone: (206) 725-4600 Fax (206) 723-2221 CLIENT FES Group PROJECT NAME Firestone Renton PROJECT NUMBER 10-0708 PROJECT LOCATION 421 Union Avenue Northeast, Renton, Washington DATE STARTED 116/11 COMPLETED 116111 GROUND ELEVATION 408 It TEST PIT SIZE 4' w x 10' I x 8' d EXCAVATION CONTRACTOR Evergreen Or -Site GROUND WATER LEVELS: EXCAVATION METHOD Steel -track excavator AT TIME OF EXCAVATION Not encountered LOGGED BY Jeff Rabe CHECKED BY Anthony Coyne P.E. AT END OF EXCAVATION Not encountered NOTES Infittration test. iprox 21 _ yard waste old fill and rubble removed AFTER EXCAVATION Not observed w ~^ w v wm -j g c} a� Q p MATERIAL DESCRIPTION O 2Z � Q 0.0 SM Medium dense, orange -brown, silty SAND with gravel (Native) (moist) (weathered glacial till) 2.5 =' 3.5 404.5 GB 1 Dense, gray, silty SAND with gravel (glacial till) 5.0 :• a.0 402.0 Gla 2 SM :: Very dense, gray silty SAND with gravel (mast) (glacial till) 7.5 8,0 40o.a 1 1 1 1 1 1 Bottom of test pit at 8.0 feet. 1 1 I 1 1 3 1 } A-5 1 i� 1 1 1 FS OTTO ROSENAU & ASSOCIATES, INC. TEST PIT NUMBER TP -4 6747 M.L. King Way South Seattle, WA 98118 PAGE 1 OF 1 Telephone: (246) 725-4604 Fax:(206)723-2221 CLIENT FES Group PROJECT NAME Firestone Renton PROJECT NUMBER 10-4708 PROJECT LOCATION 421 Union Avenue Northeast, Renton, Washington DATE STARTED 116111 COMPLETED 116!11 GROUND ELEVATION 409 ft TEST PIT SIZE 4' w x 10' I x 7.5' d EXCAVATION CONTRACTOR Evergreen On -Site GROUND WATER LEVELS: EXCAVATION METHOD Steel -track excavator AT TIME OF EXCAVATION Not encountered LOGGED BY Jeff Rabe CHECKED BY Anthony Coyne P.E. AT END OF EXCAVATION Not encountered NOTES Infiltration test. Approx 3' yard waste, old fill and rubble removed AFTER EXCAVATION Not observed W v? WCL x W � q d MATERIAL DESCRIPTION pCL z a � Q 0.0 SM :' Medum dense, orange -brown, silty SAND with gravel (Native) (moist) (weathered glacial till) 1.0 408.0 SM ;'. Dense, gray, silty SAND with gravel (glacial till) 2.5 4.0 405.0 5.0 SM ': Very dense, gray silty SAND with gravel (mast) (glacial till) . 7.0 402.0 i Bottom of test pit at 7.0 feet. A-6 1 1 1 1 1 1 Ll SOIL CLASSIFICATION CHART NOTE: FINES ARE MATERIALS PASSING THE NO. 200 SIEVE. COARSE GRAINED SOILS RECEIVE DUAL SYMBOLS IF THEY CONTAIN BETWEEN 5% AND 12% FINES. FINE GRAINED SOILS RECEIVE DUAL SYMBOLS IF THEIR LIMITS PLOT LEFT OF THE "A" LINE WITH A PLASTICITY INDEX (PI) OF 4% TO 7%. A-7 SYMBOLS TYPICAL MAJOR DIVISIONS GRAPH LETTER DESCRIPTIONS C LEAN*�� �. WELL -GRADED GRAVELS, GRAVEL - GRAVEL GRAVELS fa'�is SAND MIXTURES, LITTLE OR NO FINES AND GRAVELLY SOILS (LITTLE OR NO FINES) °�o aoQo GP POORLY -GRADED GRAVELS, GRAVEL SAND MIXTURES, LITTLE OR NO n pn D - 00, FINES COARSE GRAINED GRAVELS WITH ° a '° GM SILTY GRAVELS, GRAVEL - SAND - SOILS MORE THAN 50% FINES O b SILT MIXTURES OF COARSE o FRACTION RETAINED ON NO. 4 SIEVE (MORE THAN 12% FINES) GC CLAYEY GRAVELS, GRAVEL - SAND - CLAY MIXTURES CLEAN SANDS sw WELL -GRADED SANDS GRAVELLY SAND SANDS, LITTLE OR NO FINES MORE THAN 50% AND OF MATERIAL IS SANDY LARGER THAN NO. 200 SIEVE SIZE SOILS (LITTLE OR NO FINES)SP POORLY -GRADED SANDS, GRAVELLY SAND, LITTLE OR NO FINES MORE THAN 50% SANDS WITH FINES SM SILTY SANDS, SAND - SILT MIXTURES OF COARSE FRACTION PASSING ON NO. 4 SIEVE (MORE THAN 12% FINES) sc CLAYEY SANDS, SAND - CLAY MIXTURES INORGANIC SILTS AND VERY FINE ML SANDS, ROCK FLOUR, SILTY OR CLAYEY FINE SANDS OR CLAYEY SILTS WITH SLIGHT PLASTICITY SILTS INORGANIC CLAYS OF LOW TO FINELIQUID LIMIT AND CL MEDIUM PLASTICITY, GRAVELLY GRAINED CLAYS LESS THAN 50 CLAAYN , SANDY CLAYS, SILTY CLAYS, SOILS =_ L OL ORGANIC SILTS AND ORGANIC SILTY = =_ CLAYS OF LOW PLASTICITY MORE THAN 50% INORGANIC SILTS, MICACEOUS OR OF MATERIAL IS MH DIATOMACEOUS FINE SAND OR SILTY SMALLER THAN SOILS NO. 200 SIEVE SIZE SILTS LIQUID LIMIT 0 0 0 CH INORGANIC CLAYS OF HIGH LADS GREATER THAN 50 PLASTICITY OI„ I ORGANIC CLAYS OF MEDIUM TO HIGH PLASTICITY, ORGANIC SILTS HIGHLY ORGANIC SOILS ` ` PT PEAT, HUMUS, SWAMP SOILS WITH „ HIGH ORGANIC CONTENTS NOTE: FINES ARE MATERIALS PASSING THE NO. 200 SIEVE. COARSE GRAINED SOILS RECEIVE DUAL SYMBOLS IF THEY CONTAIN BETWEEN 5% AND 12% FINES. FINE GRAINED SOILS RECEIVE DUAL SYMBOLS IF THEIR LIMITS PLOT LEFT OF THE "A" LINE WITH A PLASTICITY INDEX (PI) OF 4% TO 7%. A-7 IPERCOLATION TEST DATA FORM 1 1 1 1 ORA PROJECT: Firestone Renton ORA JOB #: 10-0708 DATE: 01/08/2011 TEST HOLE #: _TP -1 DEPTH TO BOTTOM OF HOLE: _116 inches from tap casing PERCOLATION TEST BY: AGC TIME TIME INTERVAL min. READING inches DROP IN WATER LEVEL inches PERCOALTION RATE minlinch REMARKS 193.1875 13:07 0 199.1875 0 13:37 30 196.375 2.8125 14:07 30 196.,625 2.5625 14:37 30 196.75 2.4375 15:07 30 196.75 2.4375 12.3 A-8 IPERCOLATION TEST DATA FORM ORA PROJECT: Firestone Renton ORA JOB #: 10-0708 DATE: 41/0812011 TEST HOLE #: _TP -3 DEPTH TO BOTTOM OF HOLE: _116 inches from top casing PERCOLATION TEST BY: AGC TIME TIME INTERVAL READING inches DROP IN WATER LEVEL inches PERCOALTION RATE min/inch REMARKS 119.875 13:13 0 125.875 0 13:43 30 124.875 1 14:13 30 125.125 0.75 14:43 30 125.1875 0.6875 15:13 30 125.25 0.625 48 'J 1 1 1 1 1 1 u 1 PERCOLATION TEST DATA FORM ORA PROJECT: Firestone Renton ORA JOB #: 10-0708 DATE: 01/08/2011 TEST HOLE #: _TP -4 DEPTH TO BOTTOM OF HOLE: _116 inches from top casing PERCOLATION TEST BY: AGC TIME TIME INTERVAL mtn. READING inches DROP IN WATER LEVEL inches PERCOALTION RATE min/inch REMARKS 49.375 13:17 0 55.375 0 1147 30 55.3125 0.0625 14:17 30 55.125 0.25 14:47 30 55.1875 0.1875 15:17 30 55.25 0.125 240 A-10 � I F E S G r o u p ➢ Geotechnical Engineering ' ➢ Environmental Site Assessments ➢ Construction Materials Testing 1 ' March 22, 2410 ' Mr. Scot J. Dever Bridgestone Retail & Operations, LLC ' 333 E. Lake Street Bloomingdale, IL 60108 Subject: Report of Geotechnical Exploration ' Firestone Store — Renton, Washington FES GROUP Project No. SGO1006 Dear Mr. Dever: City o Renton Plan n,n ] Divisior7 4 L) ° ) 3 10J f 6'#Vla on cam, FES Group, Inc. (FES Group) has completed the requested geotechnical exploration for the above - referenced project. Our services were provided in general accordance with those outlined in the agreement for professional services between Bridgestone Retail & Operations, LLC (BSRO) and FES Group. The results of the subsurface exploration have been evaluated and are presented in this Report of Geotechnical Exploration. This report presents a review of the project information provided to us, a description of the site and subsurface conditions encountered as well as our foundation and earthwork recommendations for the proposed Firestone Store facility. The Appendices to the report contain site and boring location figures, the results of our field and laboratory testing, boring logs, and site photographs. 772 30'h Avenue North ' St. Petersburg, FL 33704 PH: (727) 576-2000 FX: (727) 576-2022 Firestone Store. Revlon WA FES Prgject Nu. SG07006 t -lurch ??. -7010 Report of Geotechnical Exp(onvion We appreciate this opportunity to provide our services to Bridgestone Retail & Operations, LLC and we look forward to serving as your geotechnical consultant throughout this project. Should you have any questions in regards to the information presented in this report, please do not hesitate to contact us at your earliest convenience. � L Sincerely, FES GROUP, INC. A4-A� Prenatt President National Client Manager w 'oma, �40270; �S TES' #on L %% Bruce A. Wolle, P E EXPIRES /3 Senior Engineer Washington Registration No. 40270 TABLE OF CONTENTS Page 1.0 EXECUTIVE SUMMARY......................................................................................................1-1 2.0 INTRODUCTION ........................................ ............................................................................. 2-1 2.1 PROJECT CHARACTERISTICS ..................... .............. ......................................... 2- 1 2.2 SITE DESCRIPTION ............................ ......... ......... .................................................. 2-1 2.3 PURPOSE AND SCOPE .................... ....................................................................... 2-2 2.4 REPORT FORMAT ........ .......................................................................................... 2-4 3.0 FIELD EXPLORATION..........................................................................................................3-1 4.0 LABORATORY TESTING.....................................................................................................4-1 5.0 GENERALIZED SUBSURFACE CONDITIONS...............................................................5-1 5.1 USGS TOPOGRAPHY SURVEY............................................................................5-1 5.2 AERIAL PHOTOGRAPH ................... ............ .................... ...................................... 5-1 5.3 SUBSURFACE CONDITIONS ................................................ .............. .................. 5-1 5.4 GROUNDWATER CONDITIONS ....... ................................................................... 5-2 5.5 SEISMIC DESIGN PARAMETERS........................................................................5-2 5.6 LIQUEFACTION POTENTIAL..............................................................................5-3 6.0 DESIGN RECOMMENDATIONS.........................................................................................6-1 6.1 GENERAL.................................................................................................................6-1 6.2 SHALLOW FOOTINGS...........................................................................................6-2 6.3 SETTLEMENT ............................................. ............................................................. 6-3 6.4 MODULUS OF SUBGRADE REACTION............................................................6-3 7.0 FLOOR SLAB...........................................................................................................................7-1 8.0 EARTH PRESSURES ON WALLS.......................................................................................8-1 9.0 PAVEMENT THICKNESS DESIGN CONSIDERATIONS.............................................9-1 9.1 SUBGRADE..............................................................................................................9-1 9.2 MODULUS OF SUBGRADE REACTION............................................................9-2 9.3 BASE..........................................................................................................................9-2 9.4 PAVEMENT DESIGN..............................................................................................9-3 10.0 CONSTRUCTION CONSIDERATIONS84 10.1 FILL PLACEMENT AND SUBGRADE PREPARATION.................................10-1 10.2 GROUNDWATER CONTROL.............................................................................10-2 10.3 TEMPORARY SIDE SLOPES.... ..................................................... ..................... 10-3 10.4 ON-SITE SOIL SUITABILITY ....................... ....................................................... 10-3 11.0 BASIS FOR RECOMMENDATIONS.................................................................................11-1 APPENDIX • Figure 1— General Site Vicinity Map • Figure 2 — Local Site Vicinity Map • Figure 3 — Boring Location Plan • Figure 4 — Topographic Map • Figure 5 — 2047 Aerial Photograph • Soil Boring Logs • Site Photographs • Liquefaction Analysis (Youd & Idriss - WEER 1997) • Geophysical Investigation Report Firestone Store, Renton, W.4 tFES Project No. SGO1006 1.0 EXECUTIVE SUMMARY A4arch 22, 2010 .Report of Geotechnical Exploration Based on the results of our subsurface exploration program, the following executive summary is presented. The subject site is planned to be located at 421 Union Avenue NE in Renton, Washington. The existing ground surface appeared to be level with portions of undeveloped and rough graded areas consisting of partial asphalt and concrete paved surfaces, construction debris, rock piles, scrub vegetation, and grass. Underground utilities including natural gas, domestic water, electricity, telephone, storm/sanitary sewer, and foundation support structures were identified at the subject property by use of electromagnetic (EM) and ground penetrating radar (GPR). The presence of metallic debris, piping, conduit, and buried concrete structures including foundations and slabs were also detected. Based on the size and extent of the detection, these items do not appear to be of significant concern with respect to subsurface earthwork and site development. However, the contractor should be prepared for removal of buried concrete structures, metal piping, and construction debris_ Surface water due to recent rainfall events was observed to be present on the ground surface. The borings indicated the subsurface soils generally consisted of dense to very dense poorly -graded silty SAND (SP -SM) and silty sand FILL (SM) with gravel and rock particles underlain by glacial till that extended to boring termination at an approximate maximum depth of 50 feet below ground surface. Although some difficult excavation should be expected, subsurface formations requiring rock -type excavation operations (such as blasting and/or percussion hammers) were not encountered during our subsurface exploration. • Based upon our evaluation and analyses, these soils are capable of supporting the proposed structure on shallow foundations with proper subgrade preparation. Based upon the anticipated light ' construction and recommended site preparation, shallow foundations may be designed for a net maximum allowable bearing pressure of at least 3,000 pounds per square foot (psf)_ • The soils excavated from foundation and/or utility areas are expected to predominately consist of silty ' sand (SM) and gravel with rock particles. Well -graded granular particles, gravel, and rock might also be present in excavated soils. These soils are expected to require moderate manipulation for use as structural fill material. • As recorded immediately after drilling during the time of our subsurface exploration, and corroborated through a visual observation of the obtained soil samples, groundwater was encountered at an approximate depth of 25 feet below ground surface elevations during the time of our subsurface exploration. • Based on our review of the International Building Code, dated 2006 with updates in 2009, and our knowledge of the general subsurface conditions at the site, we believe the site should be considered to be a Site Class D. Based on our field findings for groundwater, soil type, and thickness of layers, we expect liquefaction -induced and surface venting (dry) settlement due to seismic influence to be negligible and less than '/4 inch at the subject site. • Based upon our evaluation and analyses, the subsurface conditions encountered should be acceptable for construction and support of a flexible and/or rigid pavement structure. Firestone Store, Renton, WA FES Project No. SG0106 2.0 INTRODUCTION 2.1 PROJECT CHARACTERISTICS The proposed facility is planned to consist of the construction of a single -story structure, similar to the illustrated structure, and include a series of automotive service lifts and an automotive service pit which are expected to extend to an approximate depth of 10 feet below the existing ground surface elevations. The site is understood to include approximately 52,990 square feet, with the structure expected to encompass an area of March 22, 2010 Report of Geotechnical Fxploration approximately 7,653 square feet and include an automobile service pit extending to an approximate depth of nine feet below the existing ground surface elevations. Primary support of the structure is expected to be provided by load-bearing reinforced masonry walls. The floor of the building is anticipated to be constructed as a concrete slab -on -grade. The finished grades of the facility area are expected to generally coincide with the existing grade levels. The maximum loadings associated with the proposed structure were not available at the time of this report. Based upon our extensive experience with similar projects, however, the maximum loadings associated with the proposed structures are expected to be as follows: Wall Load: 2 kips/linear ft Column Loads: 25 kips Floor Load: 100 lbs/sq ft 2.2 SITE DESCRIPTION The subject site is planned to be located at 421 Union Avenue NE in Renton, Washington. The ground surface appeared to be generally developed and level with areas of rough graded undeveloped characteristics including partial concrete and asphalt pavements, minor construction debris, rock piles, scrub vegetation, and grasses. Through the use of electromagnetic (EM) and ground penetrating radar (GPR), the site was observed to contain underground utilities including natural gas, domestic water, electricity, telephone, and storm/sanitary sewer. The presence of metallic debris, piping, conduit, and buried concrete structures including foundations and slabs were also detected. Surface water due to recent rainfall events was observed to be present in minor ponds at the existing pavement surface and some exposed soil areas. Site photographs have been included in the Appendix of this report. 2-1 Firestone Store, Renton, WA FES Project No. SGO1006 2.3 PURPOSE AND SCOPE ,March 22, 2010 Report of Geotechnical Exploration The purpose of this study was to obtain information on the general subsurface conditions at the proposed project site. The subsurface materials encountered were then evaluated with respect to the available project characteristics. In this regard, engineering assessments for the following items were formulated: • General location and description of potentially deleterious materials encountered in the borings, which may interfere with construction progress or structure performance, including existing fills or surficial/subsurface organics_ • Identification and location of potentially obstructive structures such as underground storage tanks, utilities, vaults, buried concrete slabs, foundations, pipes, and similar items that may exist in the site subsurface. • Identification of the existing groundwater levels. • Development of retaining wall design parameters, including coefficient of sliding, active, passive, and at -rest lateral soil parameters. • Evaluate the infiltration characteristics of the existing subgrade soil conditions. • Evaluation of a shallow foundation system to be used for support of the proposed structure, with a slab -on -grade floor member. Identification of recommended shallow foundation design parameters, including allowable bearing pressures, foundation levels and expected total and differential settlements. • Recommended soil subgrade preparation operations, including stripping, grubbing and compaction. Recommended engineering criteria for placement and compaction of approved structural fill materials. • Evaluation of the suitability and availability of materials on-site that may be moved during site grading for use as structural fill in the building area, as pavement subgrade fill, and as general backfill. • Presentation of construction recommendations, including expected ground water control measures, temporary slope stability recommendations, and unsuitable soil removal guidelines. 2-2 Firestone Store, Renton, W11 FES Project No. SG01006 March 22, 2010 Report of Geotechnical Explorafion The following services were provided in order to achieve the preceding objectives: • Reviewed readily -available published topographic information. This included information from Quadrangle Maps published by the United States Geological Survey (USGS). • Executed a program of subsurface exploration consisting of subsurface sampling and field testing. Four (4) Standard Penetration Test (SPT) borings were performed within the approximate building proposed foundation outline to approximate depths ranging from 10 to 50 feet below existing ground surface elevations. In each boring, soil samples were collected and SPT resistance values were measured at approximate intervals of 2'/2 feet for the top ten feet and at approximate intervals of 5 feet thereafter. Four (4) auger borings were performed within the proposed pavement areas to approximate depths of ten feet below the existing ground surface elevations. • Visually classified and stratified representative soil samples in the laboratory using the Unified Soil Classification System (USCS). Identified soil conditions at each boring location and formed an opinion of the site soil stratigraphy. • Collected groundwater level measurements • Evaluated the permeability characteristics of the existing subgrade soils based on observation of site surface drainage and infiltration of collected storm water run-off. • The results of the field exploration and laboratory tests were used in the engineering analyses and in the formulation of the recommendations. The results of the subsurface exploration, including the recommendations and the data upon which they are based, are presented in this formal written report prepared by an experienced Professional Engineer. The scope of this exploration was intended to evaluate soil conditions within the primary influence of the expected structure foundation and does not include an evaluation of potential deep soil conditions, such as mines, buried organics, wetland debris, and/or sinkholes. An evaluation of potential deep soil problems may be performed at your request and with authorization. In order to perform such an evaluation, it is expected that additional deep soil test borings and GPR would be required. The scope of our services does not include an environmental assessment or investigation for the presence or absence of hazardous or toxic materials in the soil, ground water, or surface water within or beyond the site studied. Any statements in the report regarding odors, staining of soils, or other unusual conditions observed are strictly for the information of our client. 2-3 Firestone Store, Renton, WA FES Project Alo. SG01006 2.4 REPORT FORMAT March 22, 2010 Report of Geotechnical Exploration This report begins with a discussion of the field program followed by a description of the general subsurface conditions. Evaluations are presented for the selected foundation alternative. The site vicinity maps are presented in Figure 1 and 2, the approximate soil boring locations are presented on Figure 3, the USGS vicinity map is presented as Figure 4, and the aerial photograph of the site is presented as Figure 5. The soil boring logs and site photographs are also attached to the Appendix of this report. 2-4 Firestone Stare, Renton, WA FES Project A'o. SG01006 3.0 FIELD EXPLORATION March 22, 1010 Report of Geotechnical Fxploratlon To explore the general foundation soil types and to aid in developing associated design parameters, four (4) soil test borings and four (4) soil auger borings were drilled within the proposed development area. The boring locations were determined in the field from existing ground surface features. The boring locations illustrated in the Appendix should be considered accurate only to the degree implied by the method used. If more precise locations are desired, we suggest that a Registered Surveyor be contacted. It is important to note that ground surface elevations at the boring locations were neither furnished nor determined. The approximate locations of the borings are illustrated on Figure 3, which has been included in the Appendix of this report. The soil test borings at the proposed building foundation were advanced with a truck -mounted drill rig using Hollow Stem Auger (HSA) drilling procedures. The soil test borings extended to approximate depths ranging from 20 to 50 feet below the existing ground surface elevations. The soil sampling was performed in general accordance with ASTM Test Designation D-1586, entitled Penetration Test and Split -Barrel Sampling of Soils. Samples were obtained at intervals of 21/2. feet to a depth often feet, and at intervals of 5 feet thereafter. The auger borings at the proposed asphalt pavement locations were perfonned with the use of a truck- mounted drill rig using HSA drilling procedures. The soil sampling was performed in general accordance with ASTM Test Designation D-1452, entitled Soil Investigation and Sampling by Auger Borings. These samples were taken "continuously" from the ground surface to an approximate depth of ten feet below the existing ground surface elevations. Representative portions of these soil samples were sealed in glass jars, labeled and transferred to our laboratory for classification and testing. The use of EM and GPR methods across the site indicated the presence of buried cable, conduit, and piping in minor quantities. A buried object sized approximately 2 ft by 2 ft was observed at the north central portion of the site that could be a buried sign foundation. Another buried concrete slab approximately 2ft by 2ft with metal rods at each corner was found along the east side central portion of the site. However, the detection of buried metal tanks and storage drums in good condition were not observed around the proposed building foundation outline. 3-1 Firestone Store, Renton, WA FES Project ,10. SGO1006 4.0 LABORATORY TESTING A,farch 22, 2010 Report of Geotechnical Exploration The soil samples were transported to our laboratory and were classified by the Geotechnical Engineer using the Unified Soil Classification System (USCS) in general accordance with ASTM Test Designation D-2488. Representative soil samples were selected and subjected to grain -size analysis in order to substantiate the visual soil classification and assist in evaluating the near -surface soil infiltration characteristics. Due to the structural characteristics of the proposed facility and the nature of the soils encountered, additional refined laboratory testing methods were not considered necessary. It should be noted that all soil samples will be properly disposed of 30 days following the submittal of this subsurface exploration report. 4-1 Firestone Store, Renton, WA March 22, 2010 ' FES Project No. 5G01006 Report of Geotechnical Exploration 5.0 GENERALIZED SUBSURFACE CONDITIONS j5.1 USGS TOPOGRAPHY SURVEY The topographic survey map published by the United States Geological Survey (USGS) was reviewed for ground surface features at the proposed project location (see Figure 4 in the Appendix of this report). Based on this review, the ground surface appears to be a generally level area, with the approximate natural ground surface elevation at +400 feet (above) the National Geodetic Vertical Datum of 1927 (NGVD). The ground surface within the region of the subject property appears to generally be developed, with the natural ground surface sloping gently downward toward the ! southwest. 5.2 AERIAL PHOTOGRAPH An aerial photograph, dated 2007, of the subject property was reviewed for ground surface features at the proposed project location (see Figure 5 in the Appendix of this report)_ Based on this review, the subject site appeared to be developed with partial pavement coverage as was observed during the time of our site visit. 5.3 SUBSURFACE CONDITIONS The subsurface conditions encountered at the boring locations are described on the Soil Boring Logs in the Appendix of this report. These records represent our interpretation of the subsurface conditions based on the field logs, and visual observation of field samples by an experienced Professional Engineer. The lines designating the interfaces between various strata on the Soil Boring Logs represent the approximate interface locations. In addition, the transitions between strata may be gradual. Water levels shown on the Soil Boring Logs represent the conditions only at the time of our exploration. Soil and rock conditions may vary between boring locations. The borings indicated that the existing partial asphalt concrete surface coverage was approximately one to two inches thick. Underlying the asphalt concrete, the subsurface soils generally consisted of dense to very dense poorly -graded silty SAND (SP -SM), native fill consisting of silty SAND (SM), and glacial till with well -graded gravel and rock particles that extended to boring termination at an approximate maximum depth of 50 feet below the existing ground surface. 5-1 Firestone Store, Renton, WA Map,ch 22, 2010 FES Project ho. SGO1006 Report of Geotechnical Exploraf ion The subsurface conditions encountered indicated that the subsurface soils are generally uniform within the area explored. No "raveled" conditions indicative of sinkholes, buried wetland organics, and/or mining type activity were encountered during this subsurface exploration program. The logs of all borings have been included in the Appendix of this report. These logs describe the visual characteristics of all soil strata encountered using the Unified Soil Classification System. Groundwater observations, sampling information and other pertinent field data and observations are also included. 5.4 GROUNDWATER CONDITIONS As recorded immediately after drilling during the time of our subsurface exploration, and corroborated through a visual observation of the obtained soil samples, groundwater was encountered at an approximate depth of 25 feet below the existing ground surface elevations during the time of our subsurface exploration. It should be noted that groundwater levels tend to fluctuate during periods of prolonged drought and extended rainfall and may be affected by man-made influences. In addition, a seasonal effect may also occur during which higher groundwater levels are normally recorded in rainy seasons. If the groundwater level is critical to design or construction, groundwater observation wells should be installed on-site to monitor groundwater fluctuations over a period of time and to permit more accurate determinations of wet season and dry season levels. 5.5 SEISMIC DESIGN PARAMETERS Based on field subsurface exploration results, a seismic Site Class D as defined in Table 1613.5.2 of the 2006 IBC should be used for design. Spectral response accelerations and site coefficients based on the approximate site latitude of 47.489° and longitude of -122.164° are recommended for design 0.2 Sec Spectral Res onse, Acceleration Ss (g)' 1.399 1.0 Sec Spectral Response, Acceleration S, (g)z 0.477 Site Coefficient Fa' 1.000 Site Coefficient F„4 1.523 5% Damped, 0.2 Sec Spectral Response, Acceleration SDs (g)5 0.933 5% Damped, 1.0 Sec Spectral Response , es onse, Acceleration SD, (g)6 0.484 'Figure 1613.5(3), Tigure 1613.5(4), 3Figure 1613.5.3(1), °Figure 1613.5.3(2) 5Egn 16-39 where SMs = Ss x Fa, 6Egn 16-40 where SM, — Si x F, 5-2 Firestone Store, Renton, WA March 22, 2016 FES Project No. SGO1006 Report of Geotechnical Exploration 5.6 LIQUEFACTION POTENTIAL Liquefaction potential is greatest where the groundwater level is shallow, and submerged loose, fine sands occur within a depth of about 50 feet or less. Liquefaction potential decreases as grain size, clay, and gravel content increase. As ground acceleration and shaking durations increase during an earthquake, liquefaction potential increases. Groundwater was encountered within the exploration at a depth of 25 feet below ground surface in our soil exploration. For evaluation of the liquefaction potential, the ground motion, which is designated as the SBC ground motion parameter, Soh, obtained from ASCE 7 Figure 11.4-1 and Equation 11.4-5 is 0.933g. The value of 0.9338 was reduced by 0.4 resulting in a value of 0,373g for use in performing the liquefaction analysis and settlement evaluation that is attached. Based on the analysis, we conclude that the quantity of expected settlement for the upper liquefiable layer is negligible. Based on our field findings for groundwater, soil type, and thickness of layers, we expect liquefaction -induced and surface venting (dry) settlement due to seismic influence to be less than '/a inch at the subject site. The liquefaction analysis spreadsheet has been included in the Appendix of this report. 5-3 Firestone Store, Renton, WA FES Project No. SG01006 6.0 DESIGN RECOMMENDATIONS March 21, 201(1 Report of Geotechnical Exploration The following design recommendations have been developed on the basis of the previously described project characteristics and subsurface conditions encountered during this exploration. The test boring data was evaluated using correlations between the measured standard penetration test resistances and the engineering performance characteristics of similar subsurface conditions. If there is any change in these project criteria, including project building locations on the site, a review must be made by FES Group to determine if any modifications to the recommendations will be required. The findings of such a review should then be presented in a supplemental report. After final design plans and specifications are available, a general review by FES Group is strongly recommended as a means to check that the evaluations made in preparation of this report are correct, and that earthwork and foundation recommendations are properly interpreted and implemented. 6.1 GENERAL The soil test borings indicated the subsurface soils generally consisted of dense to very dense poorly - graded silty SAND (SP -SM), fill consisting of silty SAND (SM), and glacial till with gravel and rock particlesthat extended to boring termination at an approximate maximum depth of 50 feet below the existing ground surface. Although some difficult excavation, subsurface demolition, and object removal should be expected, extensive subsurface formations requiring rock -type excavation operations (such as blasting and/or percussion hammers) were not encountered during our subsurface exploration. Based upon our evaluation and analyses, the existing soils are expected to be capable of supporting the proposed structure on shallow foundations with proper subgrade preparation. As identified by EM and GPR geophysical surveys, the potential presence of utilities and subsurface concrete structures exists at the subject site. Although nothing of significant extent was found, we recommend the contractor be prepared with heavy ripping equipment. Upon demolition and removal of such structures, the recommendations provided in the following sections for fill suitability, placement, and compaction should be used to prepare the subgrade as required for construction purposes. 6-1 Firestone Store, Renton, WA FES Project No. SG01006 6.2 SHALLOW FOOTINGS March 22, 2010 Report of Geotechnical Lrploration Fallowing removal of any existing subgrade structures, including utilities and storage tanks, the exposed surface soils should be proofrolled with a heavy self-propelled vibratory drum roller (having a static drum weight on the order of four tons) under the direction of a Geotechnical Engineer in order to confirm the ability of the soils to properly support the expected Firestone Store development. Subgrade areas considered to be unstable, if any, should be remediated as directed by the Geotechnical Engineer. Based upon the anticipated light construction and recommended site preparation, shallow foundations may be designed for a net maximum allowable bearing pressure which does not exceed 3,000 pounds per square foot (psf). The foundation and floor slab should bear on the approved natural subgrade or on properly placed and compacted fill. It is recommended that the foundation bearing soils be observed and approved by the Geotechnical Engineer. All footings should be embedded so that the bottom of the foundation is a minimum of 18 inches below the adjacent compacted grades on all sides. Strip or wall footings should be a minimum of 18 inches wide and pad or column footings should be a minimum of 24 inches wide. The minimum footing sizes should be used regardless of whether or not the foundation loads and allowable bearing pressures dictate a smaller size. These minimum footing sizes tend to provide adequate load bearing area to develop overall bearing capacity and account for minor variations in the bearing materials. It is important that the structural elements be centered on the footings such so that loads are transferred evenly, unless the footings are adequately proportioned for eccentric loads. 6-2 Firestone Store, Renton, WA FES Project No. SGO1006 6.3 SETTLEMENT March 22, 2010 Report of Geotechnical Exploration The settlement of shallow foundations supported on the soils should occur as the loads are applied. Provided that the recommended subgrade preparation operations are properly performed, the total settlements of isolated columns and wall footings should not exceed 3/4 inches, with differential settlements approximately 50 percent of the total settlements. Differential settlements of these magnitudes are usually considered tolerable for the anticipated construction; the tolerance of the proposed structure to the predicted total and differential settlements should be confirmed by the Structural Engineer. 6.4 MODULUS OF SUBGRADE REACTION Based upon the soil conditions encountered at the proposed site and the recommended site preparation operations presented in the Construction Considerations section of this report, the modulus of vertical subgrade reaction (k) for the shallow soils is expected to be on the order of 180 pounds per square inch per inch of vertical deflection (pci) for a unit footing dimension of one foot by one foot. For larger foundations, the k -value should be reduced in accordance with the following equation: 2 K = K, B+1 2B Where B is the foundation width in feet. It should be noted that this value is based on typical values in published literature; a plate load test may be performed to more accurately assess the actual modulus of vertical subgrade reaction. 6-3 Firestone Store, Renton, WA FES Project No. SG0717176 7.0 FLOOR SLAB March 22, 2010 Report of Geotechnical Exploration The floor stab may be safely supported as a slab -on -grade member provided that any undesirable materials are removed and replaced with controlled structural fill. Due to the competence of the materials encountered underlying the subject site, it is expected that "floating" floor slabs (that is, generally ground -supported and not rigidly connected to walls or foundations) will provide satisfactorily performance. Floating floor slabs tend to reduce the possibility of cracking and displacement of the floor slab due to differential movements between the slab and the foundation. Due to the granular nature of the soils encountered, a capillary break is not considered to be necessary. It is recommended that the granular subgrade be covered with a lapped polyethylene sheeting in order to reduce the potential for floor dampness which can affect the performance of glued the and carpet, if any are used. The polyethylene sheeting should consist of a 10 -mil single layer of non -corroding, non -deteriorating polyethylene sheeting material placed so as to minimize seams and to cover all of the soil below the building floor stab. This membrane should be cut in a "cross shape" to allow for pipes or other penetrations and the membrane should extend to within 'h inch of all such pipes or penetrations. All seams of the membrane should be lapped at least 12 inches. Punctures or tears in the membrane should be repaired with the same or comparable material and sealed in a waterproof manner. The performance of concrete floor slabs is also affected by the concrete mix that is used. A relatively high water -cement ratio of the concrete can cause aesthetic disruptions, such as unsightly slab "curling" and shrinkage cracking. Also, an additional waiting period may be required prior to installing moisture -sensitive floor covering because of the moisture loss from the concrete floor slab. For these reasons, we recommend that a concrete mix design be selected with a water -cement ratio not exceeding 0.45. 7-1 Firestone Store, Renton, WA March 22, 2010 FES Project Alo, SGO1006 Report of Geotechnical Exploration 8.0 EARTH PRESSURES ON WALLS Due to the automobile service pit associated with the proposed project, some earth retaining walls are expected to be required. These retaining walls should be designed to resist pressures exerted by the adjacent soils. For walls that are not restrained during backfilling, and are free to rotate at the top, active earth pressures should be considered in their design. Walls that are restrained should be designed assuming using at -rest pressures. Recommended soil parameters for the near -surface granular soils encountered are presented below: Total Unit Weight, Ww = 120 lbs/f1:3 At -rest Soil Pressure, Ko = 0.50 Active Soil Pressure, Ka = 0.33 Passive Soil Pressure, Kp = 3,00 Coefficient of Sliding Friction, f = 0.40 The above recommended pressures assume that adequate drainage is provided behind the walls to prevent the build-up of excess hydrostatic pressures. This can be achieved by installing drains, using geotextiles or backfilling with free -draining granular material, in association with adequate weep holes. In order to reduce the loads being applied to the underground foundation walls and to promote positive water drainage, it is recommended that a granular backfill be placed directly behind the walls and extended laterally a minimum distance equal to the wall height. These granular soils should be relatively clean, free -draining granular materials containing less than five percent passing the No. 200 sieve (0.074 mm). Positive drainage of these backfill soils should also be provided by means such as "sock" enclosed perforated pipe toe drains. Wall rotation may be reduced by tying the wall directly into the floor slab. It is also important to note that wall damage due to excessive compaction or vibration may be avoided by utilizing hand -operated mechanical tampers. If these are used to compact the granular materials; heavy compaction equipment should not be allowed within ten feet of the walls. The compaction behind these walls should be in the range of 93 to 97 percent of the Modified Proctor maximum dry density (ASTM D-1557). S-1 Firestone Store, Renton, TYA March 21, 1010 FES Project No. SG01006 Report of Geotechnical Exploration 9.0 PAVEMENT THICKNESS RECOMMENDATIONS It is understood that it is considered desirable to use both flexible (Asphaltic Concrete) and rigid (Portland Cement) pavement section within the proposed pavement areas. Therefore, the pavement recommendations presented in the following sections are considered minimum for the site, soil and limited traffic conditions expected. The final pavement thickness design should be determined by the project civil engineer using information obtained during the subsurface exploration program and an analysis of anticipated traffic conditions. 9.1 SUBGRADE ' The test boring results indicated the subsurface soils generally consisted of dense to very dense poorly - graded silty SAND (SP -SM) and silty SAND (SM) fill with gravel and rock particles. Based upon our ' evaluation and analyses, the soils should be acceptable for construction and support of a flexible type pavement section after proper subgrade preparation, provided that drainage controls are implemented. The existing surface soils should be proofrolled with a heavy self-propelled vibratory drum roller (having a static drum weight on the order of four tons) under the direction of a Geotechnical Engineer in order to confirm the ability of the soils to properly support the expected building development. Non - vibratory compaction is recommended within areas which are located within 50 feet of existing structures, including underground utilities. The subgrade soils encountered tend to be moisture sensitive and may become unstable with increases in moisture content, such as occur during storm events and frost/freezing events. In order for a pavement to perform satisfactorily, the subgrade soils must have sufficient strength and be stable enough to avoid deterioration from construction traffic, support the paving equipment, and resist wheel loads from traffic. In addition, in order to reduce the effects of adverse weathering events, it is considered essential that the construction area be sloped to provide positive drainage away from the construction areas and that any trapped surficial water be promptly removed from the construction area. OF Firestone Store, Renton, WR March 22, 2010 FESProject,No, SG01006 Report of Geotechnical Exploration Following approval of the Geotechnical Engineer, the pavement subgrade should be compacted to a minimum depth of 12 inches to at least 98 percent of the Modified Proctor maximum dry density (ASTM D1557). Any fill used to elevate the cleared pavement areas to subgrade elevation should consist of reasonably clean well -graded to fine sands, uniformly compacted to a minimum density of 98 percent of the soil Modified Proctor maximum dry density (ASTM DI 557). It is important to note that no California Bearing Ratio (CBR) tests were requested or performed during this subsurface exploration program. It is recommended that during the pavement design phase, CBR testing be performed on the natural subgrade materials and/or the proposed structural fill materials, as appropriate. Based on our experience with similar materials, the soils ecountered across the subject site during the time of our subsurface exploration are expected to have a CBR value on the order of ten (10). 9.2 MODULUS OF SUBGRADE REACTION Based upon the soil conditions encountered at the proposed site and the recommended site preparation operations presented in the Construction Considerations section of this report, the modulus of vertical subgrade reaction (k) for the shallow soil is expected to be on the order of 180 pounds per square inch per inch of vertical deflection (pci). 9.3 BASE Base material should meet Washington Department of Transportation (WSDOT) requirements, including compaction to 98 percent of its maximum dry density as determined by the Modified Proctor Test (ASTM D-1557) and a minimum California Bearing Ratio (CBR) of 100 percent. Traffic on the subgrade areas should be avoided before the base is placed to avoid rutting. Minimizing infiltration of water into the subgrade and rapid removal of subsurface water are essential for the successful long-term performance of the pavement. Both the subgrade and the pavement surface should have a minimum slope of one-quarter inch per foot to promote surface drainage. Edges of the pavement should be provided a means of water outlet by extending the aggregate base course through to daylight or to surface drainage features such as storm inlets. 9-2 Firestone Store, Renton, WA FES Project No. SGO1006 9.4 PAVEMENT DESIGN Our analysis was performed based on the following design criteria. Standard Duty Pavement March 22, 2010 Report of Geotechnical Exploration • Design Reliability = 85% at an overall standard deviation of 0.45 for flexible pavements and 0.35 for rigid pavements; • Initial Serviceability = 4.2; Terminal Serviceability = 2.0; • Minimum Asphalt thickness = 2 inches • Minimum concrete thickness = 5 inches Heavy Dutv Pavement • Design Reliability = 85% at an overall standard deviation of 0.45 for flexible pavements and 0.35 for rigid pavements; • Initial Serviceability = 4.2; Terminal Serviceability = 2.0; • Minimum asphalt thickness = 3 inches • Minimum concrete thickness = 6 inches Flexible Pavement Structural Sections The following pavement designs are based upon the design methods described in the AASHTO Guide for Design of Pavement Structures 1993 published by the American Association of State Highway and Transportation Officials (AASHTO). These designs present the Structural Number and the 18 -kip equivalent single -axle load applications for the pavement sections presented. Pavement ,Duty. Recommended Pavement Structural Section Pavement Structural Number 1'81UP Equivallent Single Axle Load APPlications Standard 2 -Inch Surface Course Asphalt 2.0 200,000 6 -Inch Aggregate Base Course Heavy 3 -Inch Surface Course Asphalt 2.8 2,000,000 8 -Inch Aggregate Base Course 9-3 Firestone Store, Renton, WA FES Project No. SGO1006 Rigid Concrete Pavement Harch 22, 2010 Report ajGeotechnical Exploration As an alternate to the above flexible pavement design, a rigid concrete pavement design could be used. It is recommended that the concrete pavement incorporate the following design criteria. • Minimum concrete modulus of rupture of 500 psi at 28 days. • Minimum concrete elastic modulus of 3,600,000 psi at 28 days. • Effective modulus of subgrade reaction of 160 pci. • Load transfer coefficient of 3.2. • Drainage Coefficient of 1.0 In addition, in order to increase the structural rigidity of the concrete pavement section, a reinforcing steel mat, preferably size ##3 steel bars placed sixteen inches on center, may be used. The following pavement designs are based upon the design methods described in the AASHTO Guide for Design of Pavement Structures 1993 published by the American Association of State Highway and Transportation Officials (AASHTO). These designs present the recommended range of 18 -kip - equivalent single axle loads for the "standard duty" and "heavy duty" pavement sections presented. Pavement Pavement Structural Section 18 Kip Duty Equivalent Single Axle Loads Standard 5 -Inch Portland Cement Concrete 400,000 12 -Inch Compacted Subgrade Heavy 6 -Inch Portland Cement Concrete 900,000 12 -Inch Compacted Subgrade 9-4 Firestone Store, Renton, Wil .+March 22, 2010 FES Project No. SGD1006 Report of Geotechnical Exploration 10.0 CONSTRUCTION CONSIDERATIONS 10.1 FILL PLACEMENT AND SUBGRADE PREPARATION The following are our recommendations for overall site preparation and mechanical densification work for construction of the proposed development, based on the anticipated construction and our boring results. These recommendations should be used as a guideline for the project general specifications prepared by the Design Engineer. Prior to construction, the location of any existing underground utility lines within the construction area should be established. Provision should then be made to relocate any interfering utility lines from the construction area to appropriate locations. In this regard, it should be noted that if underground pipes are not properly removed or plugged, they may serve as conduits for subsurface erosion which subsequently may result in excessive settlements. 2. Following removal of the existing structure, including the underground structures (such as foundations) the exposed subgrade should be evaluated and proofrolled with a heavy self-propelled vibratory drum roller (having a static drum weight on the order of four tons), as directed by FES GROUP to confirm that all unsuitable materials, if any, have been removed and that the soils are capable of supporting the proposed structure on shallow foundations. Careful observations should be made during proofrolling to help identify any areas of soft yielding soils that may require over -excavation and replacement. 3. It is recommended that within the building area, the natural ground be compacted to a dry density of at least 95 percent of the Modified Proctor Test maximum dry density (ASTM D-1557) to a minimum depth of one foot below stripped grade. Within the pavement area, the natural ground be compacted to a dry density of at least 98 percent of the Modified Proctor Test maximum dry density to a minimum depth of one foot below stripped grade. 4. Following satisfactory completion of the proo#rolling and compaction operations, the proposed structure area may be brought up to finished subgrade levels, if required. Fill should consist of material with less than 12 percent passing the No. 200 sieve and be free of rubble, organics, debris and other unsuitable material. Fill should be tested and approved by FES GROUP prior to acquisition. Approved fill should be placed in loose lifts not exceeding twelve inches in thickness. Within the building area, the fill should be compacted to a dry density of at least 95 percent of the Modified Proctor Test maximum dry density; within the pavement area, the natural ground be compacted to a dry density of at least 98 percent of the Modified Proctor Test maximum dry density. HM Firestone Store, Renton, JVA FESProject Alo. SG01006 March 22, 2010 Report ofGeofechnical Exploraiion Soil moisture content may need to be controlled in order to facilitate proper compaction. If additional moisture is necessary to achieve the compaction objectives of imported fill, then water should be applied in such a way that will not cause erosion or removal of the subgrade soils. A moisture content within two percentage point of the optimum indicated by the Modified Proctor Test (ASTM D-1557) is recommended prior to compaction of the natural ground and fill. 6. It is recommended that all foundation excavations be observed and evaluated by the Geotechnical Engineer or his representative to explore the extent of any fill and excessively loose, soft, or otherwise undesirable materials. The foundation bearing surfaces should be compacted to a dry density of at least 95 percent of the Modified Proctor Test maximum dry density to a minimum depth of one foot below the foundation bearing elevations. If soft pockets are encountered in the footing excavations, the unsuitable materials should be removed and the footings may be located at a lower elevation. Alternatively, the proposed footing elevations may be re-established by backfilling after the undesirable material has been removed. It is recommended that this backfilling be done with a very lean concrete or open -graded crushed stone approved by the Geotechnical Engineer. A representative from FES GROUP should be retained to provide on-site observation of earthwork and ground modification activities. Density tests should be performed within the top one foot of compacted existing ground, after each fill lift, and at the bottom of foundation excavations. It is important that FES GROUP be retained to observe that the subsurface conditions are as we have discussed and reported herein, and that foundation construction, ground modification and fill placement are in accordance with our recommendations. 14.2 GROUNDWATER CONTROL The existing near -surface soils consist of poorly -graded silty SAND (SP -SM) and silty sand fill that tends to allow stormwater to permeate the ground surface. In this regard, it is expected that satisfactory dewatering may be readily provided by pumping from sump areas. Soils exposed in the bases of all satisfactory foundation excavations should be protected against any detrimental change in conditions, such as physical disturbance or rain water. Surface runoff water should be drained away from the excavations and not be allowed to pond. If possible, all foundation concrete should be placed the same day that the excavations are made. If this is not possible, the foundation excavations should be adequately protected in the interim. 10-2 Firestone Store, Renton, WA FES Project No. SGO1006 10.3 TEMPORARY SIDE SLOPES A9arch 21, 2010 Report of Geotechnical Exploraiion The side slopes for temporary excavations are expected to remain stable at two horizontal to one vertical (2H: IV) for short dry periods of time to a maximum excavation depth of ten feet. Where restrictions do not permit slopes to be constructed as recommended above, the excavation should be shored and braced in accordance with current OSHA requirements. During foundation construction, excavated materials should not be stockpiled at the top of any slope within a horizontal distance equal to the excavation depth. 10,4 ON-SITE SOIL SUITABILITY All materials to be used for backfill or compacted fill construction should be evaluated and, if necessary, tested by FES GROUP prior to placement to determine if they are suitable for the intended use. In general, based upon the boring results, the poorly -graded silty sand materials are considered to be SUITABLE for use as structural fill. Suitable structural fill materials should consist of material with less than 12 percent passing the No. 200 sieve, plasticity index (Pi) of less than 15, and be free of rubble, organics, ice clumps, clay, debris and other unsuitable material, and be comprised of material which is smaller than 4 -inches in any dimension. Any off-site materials used as fill should be approved by FES GROUP prior to acquisition. 10-3 Firestone Store, Renton, WA :March 22, 2010 ' FES Project No. SG01006 Report of Geotechnical Exploration 11.0 BASIS FOR RECOMMENDATIONS Our professional services have been performed, our findings obtained and our recommendations prepared in accordance with generally accepted geotechnical engineering principles and practices. This company is not responsible for the conclusions, opinions or recommendations made by others based upon this data. The scope of the exploration was intended to evaluate soil conditions within the primary influence of the proposed structure and does not include an evaluation of potential deep soil conditions, such as mines and/or sinkholes. The analysis and recommendations submitted in this report are based upon the data obtained from the soil borings performed at the locations indicated. Regardless of the thoroughness of a geotechnical exploration, there is always a possibility that conditions between borings will be different from those at specific boring locations and that conditions will not be as anticipated by the designers or contractors. In addition, the construction process itself may alter soil conditions. If any subsoil variations become evident during the course of this project, a re-evaluation of the recommendations contained in this report will be necessary after we have had an opportunity to observe the characteristics of the conditions encountered. The applicability of this report should also be reviewed in the event that significant changes occur in the design, nature or location of the proposed construction. The recommendations provided herein are based in part upon project information provided to us and they apply only to the specific project and site discussed in this report. If the project information is incorrect or if additional information is available, the correct or additional information should be conveyed to us for review. Our recommendations may then be modified, if necessary. Experienced geotechnical personnel should observe and document the construction procedures used and the conditions encountered. Unanticipated conditions and inadequate procedures should be reported to the design team. We recommend that the owner retain FES GROUP to provide these services based upon our familiarity with the project, the subsurface conditions, and the intent of the recommendations and design criteria. APPENDIX FIGURES %%bklbe) [eland a �TrirftFngers Camarta Smakey Paint Irt Angeles Part Townsend Fort Plagler 4 South Forty SnllaguamM Motet Agnew a T 3 State Park Tulaii 9 : oryalte. Sequ[m 5�5 M arysville 9igFar SIDan P" Port Hadlock �A1txlnt �M"W 835 R Dungeness a ake Stevens C* Campo �RrxndlMr:ftl.airi 1 ISLAND 3 P99N : ft Peak Discovery '. 2 A L L A M Bay Mukilteo Snohomish Won reek �'' 101. Leke,wane M01 Creek 2' Sultan E 99 old Bw tAa.lrlI� id 4 00 oe Edmonds �.ynfkwood 522 JEFFERSON I�° S N O H d M I lrH., n 743 ft. Tunnel Richmond Highlands,, YountlakeTerrace .North c1[y .----- --. _—.., _ ..._._.... . kraal Pant Creek Suquamish, o -. �� uvatE mom IylourllJuPitef Shoreline Sheri4an8each Id�c Ducksbush - r s s, Duckabush ;_ tCirkland° �edmond 203 Skykornisl ro+ Sikverdale Bairibndge 4alte _. JP, 52t} Tplt cork Quinault � & Island Mount FSySfl. 4 Eriands Point Sedlt�e — 1101levue 202 Baker-Snoqualmie Aiantsk-lw Tracyton' �1 5+rogrralnire National Forest Want K1TSP.F t;9 land tag arrow astsivv i Marchester While _ Mourilan East rort� CAIsr n Mawr lssaq NOrSh Bend C-0101 CushLake orchard Cushman Shorewood a OR is ! Forest Tahuya Buden I N G � Vashon _riq,+akr aider Des Sent iss Ceti Moines 515 Summit SITE jFederal Wayo Covington Gig Harbor' 16, Auburn Green M A S LO N Tacoma University Pacific Place n Grass eShallOrt a - _ Fife North Puyallup Enumclaw PAOU'lawi L.akewoolio Puyallup Bonney Buckle}• Spam take b Wend Lake W A S H I N G T O N Th panaway} Frederickson G,�r7orr BOR Plain - t lcClea Olympian .,Elk -;ALA ry a 507 167".leans, 1 umwatap P' ! E R C E HuckAefberry Maicne - Fort Lewis 7 Spukwush Creek P` Military Creek yeas;, Reservation Meadow Cres* Mt. Rainier White H U R S T© N Natir.nal Park NORTH FES GROUP, INC. GEOTECHNICAL, ENVIRONMENTAL &CONSTRUCTION INSPECTION SERVICES 772 30TH AVENUE NORTH ST. PETERSBURG, FLORIDA 33704 PHONE: 727-576-2000 FAX: 727-576-2022 DATE: SCALE: FES REPORT NO: MARCH 22, 2010 NIA I SGO1006 FIRESTONE STORE 421 UNION AVENUE NE RENTON, KING COUNTY, WASHINGTON FIGURE — I GENERAL VICINITY MAP y 1 NORTH FES GROUP, INC. FIRESTONE STORE GEOTECHNICAL, ENVIRONMENTAL &CONSTRUCTION INSPECTION SERVICES 421 UNION AVENUE NE 772 30TH AVENUE NORTH RENTON' KING COUNTY, WASHINGTON ST. PETERSBURG, FLORIDA 33704 SITE BOUNDARIES ARE APPROXIMATE PHONE: 727-576-2000 FAX: 727-576-2022 DATE: SCALE: FES REPORT NO: FIGURE — 2 MARCH 22, 2010 NIA SGO1006 SITE VICINITY MAP m m CL C rn 0`. 7 < Q D Z LU LU m 3 rTI Ri 1'l NE 12th St NE 12th St d Do ^ SE-412th sl _v n sE 1131h St o NE 10th St m — SE:%'ffi St �,� ONE,Bttt SI $ i{iwam.; Park z `, LU NE Sth St Z F ¢ Z c 4 ' ro NE 7th CL Z i > os '� NE stn P1 -SITE s � w ro NE 6th St - m- o LU 'I 4th ,St 4th St SI 42$th E 3rd S. Std Greenwoods Cemetery > N CD 9DO N� �� jO1 m `si 9 Ml Calm Cemetery QRenton SE 2nd Pt SE 136th St `.i SE at"", SX SE 138th PI SE 5fh 44 5E 142nd St nth'` S<'-- 144th St SE 145th c � Map4wom p °',y Go" Course S Maplawood., 1 NORTH FES GROUP, INC. FIRESTONE STORE GEOTECHNICAL, ENVIRONMENTAL &CONSTRUCTION INSPECTION SERVICES 421 UNION AVENUE NE 772 30TH AVENUE NORTH RENTON' KING COUNTY, WASHINGTON ST. PETERSBURG, FLORIDA 33704 SITE BOUNDARIES ARE APPROXIMATE PHONE: 727-576-2000 FAX: 727-576-2022 DATE: SCALE: FES REPORT NO: FIGURE — 2 MARCH 22, 2010 NIA SGO1006 SITE VICINITY MAP a o NE Aft PC El nr� xv� , f I %nom II,[[[yyy��� — •--- �, 110' j ..... II �_ I I �I I g5 � �AB•2 i i �� W Q I I � S I s¢ I I I I o - -- "— rsatou� Iq _�! ITQ' w� b1 L -MOTO r7wj- 30-0' f - -- -- --. IlkI0 .07 I NORTH FES GROUP, INC. FIRESTONE STORE GEOTECHNICAL, ENVIRONMENTAL & CONSTRUCTION INSPECTION SERVICES 421 UNION AVENUE NE 772 30 AVENUE NORTH 30TH RENTON, KING COUNTY, WASHINGTON ST. PETERSBURG, FLORIDA 33704 PHONE: 727-576-2000 FAX: 727-576-2022 DATE: SCALE: FES REPORT NO: FIGURE - 3 MARCH 22, 2010 N/A SGO1006 TEST BORING LOCATION PLAN i I I I I 1 I 1 I I I Source: USGS 7.5 Minute Series Renton, Washington Quadrangle Topographic Map SITE BOUNDARIES ARE APPROXIMATE h. t NORTH FES GROUP, INC. FIRESTONE STORE GEOTECHNICAL, ENVIRONMENTAL & CONSTRUCTION INSPECTION SERVICES 421 UNION AVENUE NE 772 30T" AVENUE NORTH RENTON, KING COUNTY, WASHINGTON ST. PETERSBURG, FLORIDA 33704 PHONE: 727-576-2000 FAX: 727-576-2022 DATE: SCALE: FES REPORT NO: FIGURE — 4 MARCH 22, 2010 N/A SGO1006 TOPOGRAPHIC MAP tm Vo ,r ` - ' .+*a. 41* NORTH 1 FES GROUP, INC. FIRESTONE STORE GEOTECHNICAL, ENVIRONMENTAL & CONSTRUCTION INSPECTION SERVICES 421 UNION AVENUE NE 772 30TH AVENUE NORTH RENTON' KING COUNTY, WASHINGTON ST. PETERSBURG, FLORIDA 33704 PHONE: 727-576-2000 FAX: 727-576-2022 DATE: SCALE: FES REPORT NO: FIGURE - 5 MARCH 22, 2010 N/A SGO1006 AERIAL PHOTOGRAPH SOIL BORING LOGS D SOIL CLASSIFICATION L E SAMPLES PL(�i} NM L Pio) I REMARKS: N -COUNT P AND REMARKS E L cuttings. E D Y t FINFS (%) H V SEE KEY SYMBOL SHEET FOR EXPLANATION OF N N P a • SPT (bpo (ft SYMBOLS AND ABBREVIATIONS BELOW SYMBOLS D (ft) T E N G b 10 20 30 40 SU 60 70 BU 90 100 Gray brown poorly graded silty SAND (SP -SM) with gravel 400.0 and rock fragments, dense to very dense, medium moisture, and low to medium plasticity. 5 395.0 — 5 SPT -L 4-2-3 7 l0 Gray and dark brown silty SANb (SM) with gravel and rock 390.0 110 fragments, dense to very dense, medium moisture to wet, and SPT -2 2-6-6 low to medium plasticity. 15 385.0 — 15 SPT -3 9-5014" 20 Glacial till with well -graded granular particles, gravel, and 380.0 X 20 rock fragments, SPT -4 33-5011" 25 375.0— 25 SPT -5 50r3" 40 30 Increased rock fragments, wet, very dense. 370.0 — 30 SPT -6 5014" 35 365.0 35 SPT -7 5013" 40 40 360.0 40 SPT -8 5014" 10 45 355.0 45 50 3500 50 SPT -9 X 50i I" FIELD ENGINEERING OBSERVATIONS: Approximate test boring location at northeast corner of 55 proposed building as shown on Figure 3. 345.0 55 Groundwater encountered at approximately 25 feet below In ground surface. ':nn n L- - . . I DRILLER: Boretec, Inc. EQUIPMENT: EC -55 METHOD: Hollow -Stem Auger HOLE DIA.: 8 in REMARKS: N Count = SPT value in blows per foot (140 Ib hammer free -falling 30 inches). SPT = Standard Penetration Test (split spoon sampler). Borehole backfilled with drill cuttings. THIS RECORD IS A REASONABLE INTERPRETATION OF SUBSURFACE CONDITIONS AT THE EXPLORATION LOCATION. SUBSURFACE CONDITIONS AT OTHER LOCATIONS AND AT OTHER TIMES MAY DIFFER. INTERFACES BETWEEN STRATA ARE APPROXIMATE. TRANSITIONS BETWEEN STRATA MAY BE GRADUAL. 0 10 20 30 40 SU bU 70 W 90 100 SOIL. TEST BORING RECDRD ' PROJECT: Firestone- Renton, WA BORING NO.: BI COORD N: COORD E: DRILLED: March 10, 2010 PROJ. NO.: S00I006 PAGE I OF 1 FES - 772 30TH AVE NORTH ST PETERSBURG, FLORIDA 33704 (727) 576-2000 727 576-2022 fax � I � I DRILLER: Boretec, Inc. EQUIPMENT: EC -55 METHOD: Hollow -Stem Auger HOLE DIA.: 8 in REMARKS: N Count = SPT value in blows per foot (140 lb hammer free -falling 30 inches). SPT = Standard Penetration Test (split spoon sampler). Borehole backfilled with drill THIS RECORD 1S A REASONABLE INTERPRETATION OF SUBSURFACE CONDITIONS AT THE EXPLORATION LOCATION. SUBSURFACE CONDITIONS AT OTHER LOCATIONS AND AT OTHER TIMES MAY DIFFER. INTERFACES BETWEEN STRATA ARE APPROXIMATE. TRANSITIONS BETWEEN STRATA MAY BE GRADUAL. U W LU 7U 4U M OU W SU YU IUU SOIL TEST ROIU,, 1'G RECORD PROJECT: Firestone - Renton, WA BORING NO.: B2 COORD N: COORD E: DRILLED: March 10, 2010 PROJ. NO.: SG01006 PAGE 1 OF 1 FPS - 772 30TH AVE NORTH S T PETERSB URG, FLORIDA 33704 (727) 576-2000 727 576-2022 fax SOIL CLASSIFICATION L F SAMPLES PL %}NM®('Ln)LL Wo) P AND REMARKS E L 1 N -COUNT G E D A FINFS (%) TT SEE KEY SYMBOL SHEET FOR EXPLANATION OF E N V E N Y P �0 • SPT (bpf) SYMBOLS AND ABBREVIATIONS BELOW D (ft) T E (ft) 0 400,0 lU ZO 30 40 50 60 70 80 90 100 Gray to dark brown poorly -graded silty sand FILL (SP -SM) with rock fragments, dense, medium moisture, and low to medium plasticity. Gray brown to dark brown silty SAND (5M) with rock fragments, dense to very dense, medium moisture, and low to medium plasticity, 5 i 395.0 5 SPT -1 3-3.4 10 I { 390.0 10 SPT -2 17-18-16 15 Glacial till with well -graded granular particles and increased 395A 15 rock fragments - X SPT -3 5016" 20 i I ff 380.0 20 SPT ty f1i 22-5016" 40 -4 FIELD ENGINEERING OBSERVATIONS: Approximate test baring location at northwest corner of proposed building as shown on Figure 3. Groundwater not encountered. 25 �n 375.O a-rn n 25 DRILLER: Boretec, Inc. EQUIPMENT: EC -55 METHOD: Hollow -Stem Auger HOLE DIA.: 8 in REMARKS: N Count = SPT value in blows per foot (140 lb hammer free -falling 30 inches). SPT = Standard Penetration Test (split spoon sampler). Borehole backfilled with drill THIS RECORD 1S A REASONABLE INTERPRETATION OF SUBSURFACE CONDITIONS AT THE EXPLORATION LOCATION. SUBSURFACE CONDITIONS AT OTHER LOCATIONS AND AT OTHER TIMES MAY DIFFER. INTERFACES BETWEEN STRATA ARE APPROXIMATE. TRANSITIONS BETWEEN STRATA MAY BE GRADUAL. U W LU 7U 4U M OU W SU YU IUU SOIL TEST ROIU,, 1'G RECORD PROJECT: Firestone - Renton, WA BORING NO.: B2 COORD N: COORD E: DRILLED: March 10, 2010 PROJ. NO.: SG01006 PAGE 1 OF 1 FPS - 772 30TH AVE NORTH S T PETERSB URG, FLORIDA 33704 (727) 576-2000 727 576-2022 fax DSOIL CLASSIFICATION L E SAMPLES PL (%) NM(%) LL(°i) E AND REMARKS E L I T N -COUNT T (i E D FINES (%) H E V E Y SEE KEY SYMBOL SHF..FT FOR EXPLANATION OF N N P o SPT (hpf) (fi) SYMBOLS AND ABBREVIATIONS BELOW_ D (ft) T E v c 10 20 30 40 50 60 70 80 90 100 0 Gray and brown poorly -graded silty sand FILL (SP -SM) with 4000 rock fragments, dense, medium moisture, and low to medium plasticity. Gray to brown silty SAND (SM) with rock fragments, dense to very dense, medium moisture, and low to medium 5 plasticity. 395.0 5 j i I f SPT -1 20-28-36 10 Increased quantity of rock fragments. I G 3900- 10 SPT -2 18-2644 15 Glacial till with well -graded granular particles. 385.0 15 SPT -3 5016" 20 380.0 70 SPT -4 50/3" FIELD ENGINEERING OBSERVATIONS: Approximate test boring location at southwest comer of proposed building as shown on Figure 3. Groundwater not encountered. 2S 375.0 25 in ' 7n n DRILLER: Boretec, Inc. EQUIPMENT. EC -55 METHOD: Hollow -Stem Auger HOLE DIA., 8 to REMARKS: N Count — SPT value in blows per foot (140 Ib hammer free -falling 30 inches). SPT — Standard Penetration Test (split spoon sampler), Borehole backfilled with drill THIS RECORD IS A REASONABLE INTERPRETATION OF SUBSURFACE CONDITIONS AT THE EXPLORATION LOCATION. SUBSURFACE CONDITIONS AT OTHER LOCATIONS AND AT OTHER TIMES MAY DIFFER. INTERFACES BETWEEN STRATA ARE APPROXIMATE, TRANSITIONS BETWEEN STRATA MAY BE GRADUAL - u IV 2V SU 4U �U bU '10 SU YU 1 W SOIL TEST BORING RECORD PROJECT: Firestone - Renton, WA BORING NO.: 133 COORD N: COORD E: DRILLED: March 10, 2010 PROD. NO.. SG01006 PAGE 1 OF 1 FES - 772 30 TH AVE NORTH ST PETERSBURG, FLORIDA 33704 (727) 576-2000 727) 576-2022 fax 11 DSAMPLES SOIL CLASSIFICATION L E Hollow -Stem Auger HOLE DEA.: 8 in REMARKS: PL iia) Free -failing 30 inches), SPT = Standard Penetration Test I NM (ao) LL E PE L I N -C OUN'f a x, I. � V D Y ♦FINES (oa) [[ SEE KEY SYMBOL SHEET FOR EXPLANATION OF N N P p 0 SPT (bpf) () SYMBOLS AND ABBREVIATIONS BELOW. D (ft) T E b E N " 10 20 30 40 50 60 70 80 90 100 0 4000 Gray to brown poorly -graded silty sand FILL (SP -SM) with rock Fragments, dense, medium moisture, and low to medium plasticity. Gray and brownsiltySWN5 (SM) with well graded rock fragments, dense to very dense, medium moisture, and low to medium plasticity. 5 395.0 5 r SPT -I 28-50l6" 10 10 390.0 10 SPT -2 50/6" 15 Glacial till with well -graded granular particles. 385.0 15 SPT -3 5016" 24 380.0 20 SPT -4 — 5015" FIELD ENGINEERING OBSERVATIONS: Approximate test boring location at southeast comer of proposed building as shown on Figure 3. Groundwater not encountered. 25 375.0 25 in 17n It DRILLER: BOreteC, Inc. EQUIPMENT: EC -55 METHOD: Hollow -Stem Auger HOLE DEA.: 8 in REMARKS: N Count = SPT value in blows per foot (140 lb hammer Free -failing 30 inches), SPT = Standard Penetration Test I (split spoon sampler). Borehole backfilled with drill cuttings, THIS RECORD IS A REASONABLE INTERPRETATION OF SUBSURFACE CONDITIONS AT THE EXPLORATION LOCATION. SUBSURFACE CONDITIONS AT OTHER LOCATIONS AND AT OTHER TIMES MAY DIFFER. INTERFACES BETWEEN STRATA ARE APPROXIMATE. TRANSITIONS BETWEEN STRATA MAY BE GRADUAL. U IV 1V SV 4U ]U ou !V 6U YU IVU IL TEST BORING RECORD PROJECT: Firestone - Renton, WA BORING NO.: 134 COORD N: COORD E: DRILLED: March 10, 2010 PROJ. NO.: SG01006 PAGE I OF 1 FES - 772 30TH AVE NORTH ST PETERSBURG, FLORIDA 33704 (727) 576-2000 727 576-2022 fax D E P T H Id - 5 to 15 20 �;— 25 30 SMSSIFI(NIlN L E SAMPES PIQ NM r. IV. I T NUNT ANIREMARK N &nt-Sl%alue in blows per foot #40 Ib hammer L - e a G E D A FINES VV E V E Y SEE EIS111ISBE'i 13tiE14]NA199 D N N P a • SpTlpf) SMHANURFVIAVS BIN, D 0) T E c b ^ ^ 10 20 30 40 50 60 70 80 9 100 Gray to dark brown poorly graded silty SANIaPSMjwiih 400.0 rock fragments, dense to very dense, medium moisture, and low to medium plasticity. AU i I E .{ s j I 39.0 5 Gray and dark brown silty SAN15M)with rock fragments , i dense to very dense, medium moisture, and low to medium plasticity. 38.0 10 FIEMNGINEERING 1ERVAINS: Approximate test boring location near northeast comer of proposed parking area as shown on Figure 3. 385.0I5 Groundwater not encountered, 380.0 20 375.D z�n n 25 RIER: Bretec, Inc. EQIPMENT EO MEID bllnwgtem Auger (3W 8 in REMARK N &nt-Sl%alue in blows per foot #40 Ib hammer freefal ling 30 inches) SP FStandard Penetration first 4plit spoon sampler) Brehole backfilled with drill cuttings. IS RE@IDS A REAS19AB IN)ERPRE1110 DSURURFAF t9MS AM EMA'IN BHN. SUSURFAE GIDS ASR BINS ANfA`M MMES MAYYFER. 1NIERFAES BWEEN SICAX ARE APPROAAT. KANS11NS BWEEN SIAM MAIB GRADAL U IU LU a4 40 M 60 70 8U N 1UU SOTL� TEST BORING RECORD PROJECT: Firestone -Renton, WA BORING NO.: AB COORD N: COORD E: DRILLED: March 10, 2010 PROJ. NO.: SGO1006 PAGE 1 OF 1 FES - 772 30TH AVE NORTH ST PETERSBURG, FLORIDA 33704 (727) 576-2000 727 576-2022 fax 5 `a 3C DRILLER: SOIL CLASSIFICATION L E SAMPLES HOLE DIA.: 8 in REMARKS, PL (�/4) free -falling 30 inches). SPT = Standard Penetration Test NM (pro) LL (,o} P AND REMARKS L' L IN -COUNT T E V D Y • FINES(io} H SEE KEY SYMBOL SHEET FOR EXPLANATION OF N N P c o 0 SPT (bpf) (fi? SYMBOLS AND ABBREVIATIONS RFl.OW. D ft � } 7 L 10 20 30 40 54 60 70 80 40 100 0 400.0 Gray to dark brawn poorly -graded silty sand FILL (SP -SM) with rock fragments, dense, medium moisture, and tow to medium plasticity. AU Gray and dark brown silty SAND {SM} with rock fragments, dense to very dense, medium moisture, and low to medium plasticity - 5 —3950— 5 to 390,0 10 FIELD ENGINEERING OBSERVATIONS: Approximate test boring location near northwest corner of proposed parking area as shown on Figure 3. 15 385.0 15 Groundwater not encountered. 20 380.0 20 25 375.0 25 z�n n 5 `a 3C DRILLER: Boretee, Inc. EQUIPMENT: EC -55 METHOD: Hollow -Stem Auger HOLE DIA.: 8 in REMARKS, N Count = SPT value in blows per foot (140 Ib hammer free -falling 30 inches). SPT = Standard Penetration Test (split spoon sampler). Borehole backfilled with drill Cuttings. THIS RECORD IS A REASONABLE INTERPRETATION OF SUBSURFACE CONDITIONS AT THE EXPLORATION LOCATION. SUBSURFACE CONDITIONS AT OTHER LOCATIONS AND AT OTHER TIMES MAY DIFFER. INTERFACES BETWEEN STRATA ARE APPROXIMATE. TRANSITIONS BETWEEN STRATA MAY BE GRADUAL. U IU 2U SU 4V 3V 69 7U SU VU IOU SOIL TEST BORING RECORD PROJECT: Firestone - Renton, WA BORING NO.: AB2 COORD N: COORD E: DRILLED: March 10, 2010 PROJ. NO.: SG01006 PAGE I OF 1 FES - 772 30TH AVE NORTH ST PETERSBURG, FLORIDA 33704 (727) 576-2000 727 576-2022 fax DS(11? T SSIFIAIlO ANIREMARK I E G E L E SAMPFS bllowStem Auger El W: PW. NM 4'o 14'0 l N int =SP'Palue in blows per foot 040 Ib hammer NONT �' - - Q • FINES 4'o H 4plit spoon sampler) &ehole backfilled with drill E V DT E Y SEE KISMO 3EFR EMNAIN E) N N P o o ! SPT)pf) ft� SMOAN@t13EVIAWS BQV D (t)T E d ]D 20 30 40 50 60 70 BU Gray to dark brown poorlygraded silty sand PI$PSM) with rock fragments, dense, medium moisture, and low to0 medium plasticity, AU Gray brawn silty SAN113Mjaith tines and rock fragements, glacial till, dense to very dense, medium moisture, and low to medium plasticity. 5 10 FIEMNGINEERING WRVAIG& Approximate test boring location near southwest comer of proposed parking area as shown on Figure 3. 15 Groundwater not encountered. 20 0 ry 30 BIER: arctec, Inc. EQIPMENT EO MED bllowStem Auger El W: 8 in REMARK N int =SP'Palue in blows per foot 040 Ib hammer freefalling 30 inches) SP7;tandard Penetration ilst 4plit spoon sampler) &ehole backfilled with drill cuttings. E5 REOM A REAS&AB IN>ERPREAU f) SUSURFAE ISMS AM EMA'IL4 010. SUSURFAe &MS A'E R RIGS AN[A'W EMES MAYYFER. INERFAES BWEEN SXAA ARE APPRWA1E. KANSIUS BWEEN STAR MA'S 6RADAL 39.0 38,0 385.0 380.0 375.0 370.0 5 10 15 20 25 SOWTEST BOI UNG RECORD . PROJECT: Firestone -Renton, WA BORING NO.: AB COORD N: COORD E: DRILLED: March 10, 2010 PROJ. NO.: SG01006 PAGE 1 OF 1 FF - 772 30 TH AVE NORTH ST PETERSBURG, FLORIDA 33704 (727) 576-2000 727 576-2022 fax E SIESSIFIAIN T ANIREMARS E SEE H ISM13BE'F O EIKKNAW E) SMOANIA REV1AUS [3fY Gray to dark brown poorlygraded silty sand F11¢PSM) with rock fragmems, dense, medium moisture, and low to medium plasticity. Gray brown silty SANIOMjwith fines and rock fragements, glacial till, dense to very dense, medium moisture, and low to medium plasticity_ 5 10 FIEIINGINEERING 13ERVAINS: Approximate test boring location near southeast corner of proposed parking area as shown on Figure 3. 15 Groundwater not encountered, 20 30 TKER; l3retec, Inc. EQIPMENT E0 MEI$ hilowStem Auger 9 T S in REMAR$ N Gint;aP"palue in blows per foot Q 40 lb hammer n freefalling 30 inches) SPTStandard Penetration irst (split spoon sampler) 8rehole backfilled with drill E cuttings, IM REDEN A REASNAB INIRRPREXIN DSUBURFAE OMS AIR EMA'IN &W. SUBURFAE MINS AIR @1I9S ANDUM MMES MAUFER. IN>ERFAES BWEEN SWAT ARE APPRfMA>E. I£ANSTINS BWEEN SHAH MAM GRADAL L E SAMPES P% NM Vo IV6 E L I NONT G E n T ► FINES Qlo E VF Y N N P o n ! SPTrpf) D) T ° 400,0 — 10 20 30 40 50 60 70 80 0 100 AU t�' I1�====__====© ��l 1 -= ====IE dpm� Mi= ======® 370.0 1 1 1 1 1 1 1 1 1 1 1 1 1 1 0 10 20 30 40 50 60 70 80 6 100 SOIL TEST BORING°RECORD PROJECT: Firestone -Renton, WA BORING NO.: Aig COORD N: COORD E: DRILLED: March 10, 2010 PROJ. NO.: SG01006 PAGE I OF S - 772 30TH AVE NORTH ST PETERSBURG, FLORIDA 33704 (727) 576-2000 727 576-2022 fax cn >y �3 j p LO) Q Y co� 20 O U ', U cz a� O �-' � ?C "O O � vii Ri I O �O•, R U I b i 4-+ O r O r [4 i r V1 i 1 y Q PLO mdumm 04 cu p Q�> �� 7 �v��❑ .-7 O� 1� ❑ c cn a� j t✓ i z o r W CCL. � G Sl c � i¢ CD � O � Q 0= 3 •n O O Ln � a � a. 0 z b co or p:w u m b O U ImoF.. s. °y`�" y>d 7p CC CC V T_ A O 5.5. 7yl C C7 yr j 7' `«.-.� an .-. :� N cq v •0 'w {7� CUC .� v, yOy y cr O O - sem. 41 DD, rn bb p �_ •O �.' Cl ' C ra rn 'C v ... g.2 'Q U M N r` ino a �3 o b o bob `n E N bA� E a E in U E a; va U O 3 ° .o 6. Q a o°} v>, .r ,., v� LQ fW O • L a� �0. ¢ ul �o o o U nA �cn ° V O z� U a o i ul 0 O ❑ y d., N vm V) z o ❑ .. W O W Lr .,, 4, Q A C ❑ .0 wv� [J} V) �j C z Q ati Wzti z OF �V Q c 3v Uv7 C¢i�F-Q oVi 3" .7W U� W tc C.) z py ! o w v Z z a p Wwusv ❑�nv> Er 4 �r� Q U cd� �6) M o�� Q� o Ln U w onZva]���N� FES GROUP, Inc. ' 772 301h Avenue N. St. Petersburg, Fl. 33716 PH: 727-576-2000 FES GROUP INC. 200 Sieve Analyses Log Sheet New Firestone Store Renton, Washington FES Group Job No. SGO1006 Sample Date Material Description 1 Soil Classification Natural Moisture % % Passing 200 Sieve Tech 3109110 Auger Boring 1 at -5 to -6.5 ft below existing rade Brown Slightly Silty Sand SP -SM with Rock Fragments 9.7 11.8 NP 3109110 Boring B-2 at -5 to -6.5 feet below existing rade Dark Brown Silt Sand SM 20.0L 19.9 NP 3109110 Boring B-4 at -10 to -11.5 feet below existing rade 9.3 28.1 NP Grayish Brown Slightly Silty Sand SM with Rock Fragments 3109110 Boring B-1 at -10 to -11.5 feet below existing rade Grayish Brown Silt Sand SM 11.3 28.5 NP FES GROUP, Inc. ' 772 301h Avenue N. St. Petersburg, Fl. 33716 PH: 727-576-2000 SITE PHOTOGRAPHS Firestone Store Renton, Washington Photograph No. 1: View of subject site looking northwest from the southeastern entrance. Photograph No. 2: View of southeast corner and entrance area of the subject site. FES Group, Inc. Project Number SGO1006 Firestone Store Renton, Washington Photograph No. 3: View of the subject site looking north along Union Avenue NE with utility flags. Photograph No. 4: View of partial concrete and asphalt pavement coverage with debris and central portion of the site. FES Group, Inc. Project Number SGO1006 Firestone Store Renton, Washington Photograph No. 5: View of EM & GPR marking at the subject site with utility flags. Photograph No. 6: View of soil test boring exploration activities near the southwest portion of the site. FES Group, Inc. Project Number SG01006 Firestone Store Renton, Washington Photograph No. 7: View of existing light standard and partial pavement coverage near the southeast corner of the subject site. Photograph No. S: View of partial pavement, debris, and vegetation at central portion of the site. FES Group, Inc. Project Number SGO1006 LIQUEFACTION ANALYSIS (Youd & Idriss - NCEER 1997) 1 11 11 � I I 3, J0000w�wwoo000000o ozzzz�}}}zzzzzzzzz I i r! O_ 4 Q O O O 1 ( _ r r r N N ; 40 47 Mn If] r m to to Lo L,o us ❑ ❑ ❑ ❑ ❑ ❑ O O F o, �pp ' pp OO p O o o O G 0 0 C UY •� *'i 4 0 Gi d) d) W 4 LO N _ O N co al h UJ h N n > > > > > o r m 60 + rn m C.?I r o o O o❑❑ O❑❑❑❑❑❑ W z ol Q I0 4 4 0 0 C O 4 00 0 0 d O a� O aI al a) 7 3 N US M M 0 N a) N N a0 nY N O (O h QI O 0 O 0 O 0 O 0 O 4 O 4 O 0 O 00 Q F q �c0ay rn ma) 6) (3)a�000rr al rn rn as rn m r�ro00000006 � J w i I� v��yrvhrr.-fin»D5 M CO N O 0 o w rn _0 0_o _o Z'' �Z �cannnnr�** *ateEs i J o. 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O 7 0) O 0 O 0 p 0 4 ~ a fl M C7 M (OSS c'? m 'T qr n V Q V V, r V Ui fj W p C•I y �000006QQ00 E o 0 0 0 0 o 0 0 o o S 000000 o 0 0 o 00 °aUQOOOwwww000.0o010oQ YTTr - - - -rr�r�TTTTT -Z Z Z_Z >-} >->-Z_Z Z.Z-Z,Z:Z.Z.Z. .. . �I N Q QY rfOD' m O.Om �� j -20 NO dOOOOOOoO Lo LO O,❑.❑ ❑❑❑❑❑ o 0 0 o o 0 o O T _..... _ •• s _._. �m In0�nmmcnimmM10:dddo0olo0 Cl) rV O co N:cO O •• }Cyy�ocflmN Q[Dr~rn O 0 CL'r-O! to CD La o�G O La V OO , 'O'd! ? OO TT TT a N Q1 W ❑ to W,N ri m _...—_.. �. r .. Lol TSI {-hh ..._-..... .._ .. _ uT 04 li'i!u� O O O.u].O G o o 4 0 0 0 0 W O O',O.O O 0:0 O O O O 0 OHO O O O O SO 0 Z7— [aJ � O''O OIN O a0 Q ED io O Q o:O O 0 0 0 0 .O n5 N ... O o— T r N N Cn = M M;! O 7 0) O 0 O 0 p 0 4 ~ a fl M C7 M (OSS c'? m 'T qr n V Q V V, r V Ui fj W C�C ~ 0 0 0 0 OHO O O O CO TON N.C'1 [O")�Q VCL. J' Q F N m } c c c c c cii c g m!mn Q } 07 I� Qn� 0 ej) w Stresscalc Stress Calculations for Layers: Stress Calculations for SPT depths: At Bottom_ of Laver Total Depth (ft) Top Total Unit Total Vertical Total Effective Layer No. - - - TOP Bottom Weight (pcf) Stress (tsf) Stress is Blowcount Distance(ft) 0 15 115 0.863 0.863 - -- 2 15' 30 118 1.748 1.592 3 30' 50 120 2.948 2.168 4 999 999 0 2.948 -27.441 5 999 999 0 2.948 -27.441 1.217 1.217 25.00 26.50 50 1 6 - 999 999 0 2.948 -27.441 7 999 9991 0 2.948 -27.441 8 999 999 0 2.948 -27.441 9 999 999 - 0 2.948 -27.441 Stress Calculations for SPT depths: Page 1 SPT Total Effective Top Bottom Measured "SPT' Mid -Depth Stress @a Stress @ Depth(ft) Depth(ft) Blowcount Distance(ft) (ft) Mid -Depth (tsf Mid -Depth (tsfl 5.00 6.50 5 1 6.00 . 0.345 _... 0.345 10.00 11.50 12 1 11.00 x.633 0.633 15.00 16.50 50 1 16.00 0.922 0.922 - 20.00 - -- 21.50 50 1 . 21.00 1.217 1.217 25.00 26.50 50 1 26.00 1.512 1.480 30.00 31.50 50 1 31.00 1.808 1.620 35.00 36.50 50 1 36.00 2.108 1.764 40.00 41.50 50 1 41.00 2.408 1.908 0.00 0.00 0 0 0.00 0.000 0.000 0.00 0.00 0 0 0.00 0.000 0.000 0.00 0.00 0 0 0.00 0.000 0.000 0:00 0.00 o 0 0.00 0.000 0.000 0.00 0.00 0 - 0 -- 0.00 0.000 0.000 0.00 0.00 0 0 0.00 0.000 a.aoa 0.00 0.00 0 0 0.00 0.000 0.000 0.00 0.00 0 0 0.00 0.000 6.000 0.00 0.00 0 0 0.00 0.000 0.000 Page 1 GEOPHYSICAL INVESTIGATION REPORT ' GEOPHYSICAL. INVESTIGATION REPORT 421 UNION AVENUE NE SITE RENTON, WASHINGTON FOR FES GROUP, INC. ST. PETERSBURG, FLORIDA MARCH 2010 agoIL>:4116191-1 GEOPHYSICAL CONSULTANT Philip H. Duoos Geophysical Consultant March 22, 2010 Mr. Jeff Prenatt FES Group, Inc. 772 3e Avenue North St. Petersburg, FL 33704 REPORT: Geophysical investigation 421 Union Avenue NE Site Renton, Washington Gear Mr, Prenatt: Our Ref: 907-10 This letter report summarizes the results of the geophysical investigation that I performed on March 11, 2010 at the site. The purpose of the investigation was to locate possible small underground storage tanks (USTs) and a passible septic tank. The site is fairly flat with much of the area covered by asphalt, and the rest is grass with moderate brush and blackberry vines. An electromagnetic (EM -31) survey was made over the area of interest. Field evaluation of the data was made to locate zones with anomalies that may indicate possible buried metal These anomalies were investigated to a limited extent using ground penetrating radar (GPR). A brief ' description of the methods is attached. Three EM -31 anomalous zones were interpreted from the data, but they are not believed to indicate a typical UST. One anomalous zone near a visible concrete structure was explored with a hand shovel, and revealed a metal base for a sign post. The GPR data over the other two anomalies also seems to indicate features smaller than a UST. Their locations are also quite far from the building, and probably do not indicate a septic tank. However, the anomalies may indicate other hazards such as drums, waste debris or other metallic materials. FIELD METHODOLOGY The Interpretation Results Map (Figure 1) shows the results of the EM -31 survey at a scale of 1 inch equals 20 feet. The various site features and locations of the reference grid marks are also shown. Reference baselines were marked at 10 -foot intervals using tape measures and pink or white paint and red pin flags and yellow pin flags. The red pins flags were used to marl€. every 20 feet (0', 20'. 40', etc.) and the yellow flags mark the intervals between (at 10', 30', 50`, etc.). Most of the reference flags were left on the site to assist in locating any future work, Reference grid coordinate OE, 260N is located at the northwest corner of the site at the comer of the wooden fence. Line 260N follows along the wood fence along the north side of the site, and Line OE runs along the wood fence along the east side of the site. Electromagnetic data were recorded using a Geonics EM -31 Terrain Conductivity Meter with data digitally recorded and downloaded to a laptop computer. Data were obtained along survey lines spaced a maximum of 10 -feet apart and oriented in one direction. Additional lines around the former building slab and in the grassy area east of the former slab were spaced 5 feet apart. Data were recorded at 5 -foot intervals along each line. Philip~ H. Duces 13503 NE 78th Place, Redmond, Wagon, 98052 PH/r1425) 882-2634 Emaih geopyg*aolmo m � I 2 I EM -31 data were also recorded along numerous crosslines to assist in the data interpretation. ' Additional lines were located around the perimeter of the building while walking slowly and carefully to avoid interference from the building, and observing the instrument's meter for large deflections perhaps related to a small UST. None were observed. ' The EM -31 conductivity and inphase data contour maps are provided on Figures 3 and 4, respectively, and are at a scale of 1 inch equals 40 feet, The small "+" symbols indicate the station locations for each data point. The blue colors indicate low values, and the red colors ' indicate higher values. Figure 2 is a copy of the Interpretation Results Map at a scale of 1 inch equals 40 feet to help in orienting the data contour figures, INTERPRETATION RESULTS ' Anomalous zone AZ -1 was defined in the field with orange spray paint as shown on Maps 1 and 2. Three shallow GPR targets (1 -foot deep) were observed in AZ -1 and marked w9h orange pin flags in the field, and are shown on the map by the green circles. These targets do not show a good reflection such as from a drum in good condition or tank. They may indicate metal debris, ' or perhaps small, crushed drums. Anomalous zone AZ -2 was not defined its the field. The smaller anomalous zone is probably ' the main concentration of buried metal, but the queried line includes a larger area with lower than normal conductivity and may also indicate small amounts of scattered metal. The brush was thick in this area, but the GPR was used over a small area. The GPR data indicates a ' moderate size target (perhaps 2' x 2' in horizontal extent) at a depth of about 3 feet to the tap of the object. This GPR target was marked with an orange pin flag. AZ -3 is near a concrete slab at the surface. Some shallow digging of the area uncovered a flat ' slab of concrete with four metal rods (about 2 -inch diameter) sticking up at each corner (about 2' x 2' in extent). This is probably the base for a former sign post. A linear anomaly along Line 52E is located in a landscape island. It is only observed in the conductivity data, which probably indicates a wire cable, metal conduit or small metal pipe. If it were a large piece of burled metal, the inphase data would have been affected_ (Conductivity data is more sensitive to long, small diameter features than the inphase data.) The EM -31 data did not indicate any large elevated conductivity zones that sometimes may indicate a septic drainage field. Slightly higher values are observed in the southeast corner of the site, but are interpreted to be a result of the metal fence along the southern and eastern edges of the side. Limited GPR scanning was done over several long lines across the site, including this southwest area, and no patterns of septic drain lines were observed in the data. The use of the EM -31 provided a rapid and non -intrusive means of investigating the area of interest for possible USTs and the septic tank (assuming it had some metal reinforcement). While the brush and blackberry vines prevented a complete GPR survey of the site, the GPR did provide helpful information over the ESA -31 anomalous zones. These methods provided a non-destructive means of investigating the site for various features of interest. However, because of the numerous variables involved in geophysical investigations, there is a possibility that some features may not have been detected. Only direct observations using test pits or other means can ultimately characterize subsurface conditions. Please contact me if you have any questions or comments regarding this information, or if you require further assistance. I appreciated the opportunity to work with you on this project and look forward to providing you with geophysical services in the future. Sincerely, Philip H. Duoos Geophysical Consultant DESCRIPTION OF METHODS EL.EGTROMAGNETICS (EM -31) The EM -31 measures subsurface conductance using the principles of electromagnetic induction. The EM -31 is portable, rapid and non-destructive. It has a fixed boom containing the transmitter and receiver coils so that handling and data gathering is easily achieved by one operator. The EM -31 sends an alternating current into the transmitter coil. This alternating current generates an alternating primary magnetic Meld, which in tum induces a small alternating current in any conductive medium surrounding the transmitter coil, The I' alternating current in the conductive medium generates an alternating secondary magnetic field which is detected by the receiver coil. The EM -31 calculates the conductivity of the subsurface by comparing the primary field and the secondary field. Factors which may increase subsurface conductivities include higher moisture content, greater amounts of finer materials, increased clay and/or silt content, soil contamination and/or ground water contamination_ The presence of buried metal can also affect the conductivity data. The detectability of metal objects (buried pipes, drums, etc.) can be enhanced by measuring the change in the magnitude of the primary field (inphase component) of the induced magnetic field. The primary field is affected mainly by metal. Several factors can affect the effectiveness of the EM method including the proximity of cultural interferences (such as buildings, fences and reinforced concrete) the presence of highly conductive materials (such as clays and water), and the size, depth and conductivity contrast of the target. rI GROUND PENETRATING RADAR Some of the uses of GPR include locating buried tanks and drums, delineating boundaries of landfills and trenches, and defining voids and geologic stratigraphy. Although other techniques can also provide some of this information, GPR is less affected by cultural interferences such as overhead powedines, buildings, and fences. GPR can also provide higher resolution of the target in many cases. Depths of exploration can vary widely, from just a few feet in water saturated clayey materials to hundreds of feet in glacial ice. A variety of antennas (ranging from 80 to 900 MHz) can be used depending on subsurface conditions and the objective of the survey. Resolution of shallow objects requires higher frequencies, while ' lower frequencies words better for deeper investigations. Several factors can affect the effectiveness of the GPR method including reinforced concrete at the surface, the presence of highly conductive materials (such as clays and water), the size, depth, and physical property of the target and; in stratigraphrc investigations, the conductivity contrast between stratigraphic unds. The presence of numerous buried objects may mask objects and/or stratigraphy below them. rI GEOPHYSICAL INVESTIGATION RESULTS 421 UNION AVENUE NE SITE RENTON, WASHINGTON EXPLANATION + Reference Grid Mark Anomalous Zone Questionable Anomalous Zone 03 f GPR Target ... .,-. .--, Possible utility (Linear Anomaly) Electrical Line (marked by others) 4p (] Light Pole Base Steep Slope �-- x Chain Link Fence Depths noted on figures are estimated depths to tops of GPR targets. Philip H. Duoos, Geophysical Consultant Project No. 907-10 March 22, 2010 1 v4 r .R- 1 1 4 � i 1 M � y L f l ' A , r s 1 i V SL TL sn + r w .0. • n! x ' v4 r .R- 1 1 aYps ZP rt3N1"1 � y L f l 1 Q 1 x _ ' :Lb� -� • %.) 11-49 A �� �U)o LL wZ� Ww_Z Z�= 0Z ujoo a aZZ W W �^ N t Za m z a A �. fA 1 � 1 w \ 42 �.. .4 44 A a ' at 4 vu i T f V w r . Mr �pp - ,r V5 � Hyl u �, o z2 Q loci, �} � N o[, i LNv M tM/vIF- es wo" fwer es ! te4 y�o } 2ywr• + i 291N + + Whr 8 w � WN , + t N i • �:; Gr � Loi Joe l yIMF /f/E /S'OC JNi I" P1iA►l, ' i r F BI{I]N r +IYwv r ] } } } Qll{Yn ki h1..J * x I a ' r . D ►trv►N 3 p •� 2 �.6 irk. 1 � 1- } } f 4 94irc �, 1 } 191N 1 �` W Y } � r h0 S 1 z t I 6tPp.mr I I � I ♦ � f sl + t } i • + �r �Fnlx7 P1iA►l, ' i r F BI{I]N r +IYwv r ] } } } Qll{Yn ki h1..J * x I a ' r . D ►trv►N r % 4 r rti.+Y t►nt I irwe - a ' 1 l3� LO.f I I l! ! t J L A~�`fk. � }}J fY vy + Ai pinny , 5Lh6 A-1 INS . * . } oe ;or yae 6oi Bef /eor /int =Yd� f Ro[,K5 4 Rrxr + t 4 i • + amu+ hoo ure f} F ' i r F r f , i } } F * x it J INTERPRETATION RESULTS 2421 UNION AVENUE NE SITE RENTON, WASHINGTON ,March, 2010 FIG. 60 �, o 40- - .. r+_ 0 , ' 4 �' � . 4i` b' of .10 20-- 10 A2 ' - r U.G_ Electric o - - -- - -,- Jo SLAB 20 40 60 80 100 120 140 160 180 Catch Basin 60 Metal Fence & U.G. Electric along -40 East Edge of Site NORTH Scale: V = 40' Phil Duoos, Geophysical Consultant Project # 907-10, March 22, 2010 EM 31 CONDUCTIVITY DATA 421 Union Ave. NE, Renton, WA Range: -6 to 12 mSlmSlm Contour: 0.6 mS1m FIGURE 3 AZ -1 AZ -2 20 40 .......... 60 80 100 120 140 160 180 F 240 '-240 2 f 220-- 220 Linear AZ N: 200 1-200 1180 �� 160 G° 160 Drill Rig x 140 vJ C9 IF -1 40 .r . �.._ i AZ -3 120 a '� 'F 14 - P r 12fl 1 (Sign Base) QP `f FI I'- 100- " . _, �_ ` ,J CY 1 00 80 SLAB 60 �, o 40- - .. r+_ 0 , ' 4 �' � . 4i` b' of .10 20-- 10 A2 ' - r U.G_ Electric o - - -- - -,- Jo SLAB 20 40 60 80 100 120 140 160 180 Catch Basin 60 Metal Fence & U.G. Electric along -40 East Edge of Site NORTH Scale: V = 40' Phil Duoos, Geophysical Consultant Project # 907-10, March 22, 2010 EM 31 CONDUCTIVITY DATA 421 Union Ave. NE, Renton, WA Range: -6 to 12 mSlmSlm Contour: 0.6 mS1m FIGURE 3 AZ -1 AZ -2 ' 20 4 ...._ 60 80 100 120 140 160 180 240 240 0 220.. r -220 200 -200 ry � 180 180 1 Iso iso L 114 ❑rill Rig 140 1201. 4to 8 AZ -3 Sign Base} IX 100 80 . -80 60 �, 60 ' .1D Metal Fence & 2 U.G. Electric along 40 East Edge of Site 20. T` 6 20 0 ------------------ .................. 0 SLAB 20 40 60 80 10 120 140 160 180 ' Catch Basin ' NORTH Scale: V= 40' Phil Duoos, Geophysical Consultant Project # 907-10, March 22, 2010 EM 31 INPHASE DATA 421 Union Ave. NE, Renton, WA Range: -10 to 10 ppt Contour: 0.6 ppt FIGURE 4