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Home My WebLink AboutLUA-07-015_MiscMACLEARNSBERRY ENCINEERINC, P.S. Civil Engineers o Land Planners TECHNICAL INFORMATION REPORT ( DRAINAGE REPORT) 159 WVatt Way NE Bainbridge ISiand WA 98110 12061 842-7716 2061 780-2408 <facsimile! FOR HOUVENERSHORTPLAT 1719 MORRIS A VE. SOUTH Prepared for: PAUL HOUVENER JANUARY 2007 1(800) 600-4600 i ~:~ --·i:)Cr ·~ 2!$) Yt::::ARS98365 OF SERVICE 2408 !facsimile! P.O. BOX 65382 Port Ludlow WA {360) 437-0430 {2061780- JOB NO. 26528 TABLE OF CONTENTS I. PROJECT OVERVIEW II. PRELIMINARY CONDITIONS SUMMARY Ill. OFF-SITE ANALYSIS IV. RETENTION / DETENTION ANALYSIS AND DESIGN v. CONVEYANCE SYSTEM ANALYSIS AND DESIGN VI. SPECIAL REPORTS AND STUDIES VII. BASIN AND COMMUNITY PLANNING AREAS VIII. OTHER PERMITS IX. EROSION/ SEDIMENTATION CONTROL DESIGN X. BOND QUANTITIES WORKSHEET XI. MAINTENANCE AND OPERATIONS MANUAL Section I. Project Overview Houvener Short Plat I.) Project Overview The proposed Houvener Short Plat is 0.62 acres in size and is located immediately west of Morris Avenue So. Between South 171h Street and South 18111 Street in the City of Renton, WA. The development proposal is to subdivide the property into four single- family residential lots. The site is presently developed with an existing house, guest cottage, detached garage, and a storage shed resulting in an existing impervious surface area of 0.10 ac. The balance of the site is landscaped including sparse trees. The ground slopes moderately to the north and southwest and the underlying soils are Beausite, which are classified in SCS group "C". There are no critical areas onsite, however, the property is located in a high coal-mine hazard area. ( See attached "Coal Mine Ha:mrd Assessment" prepared by AESI ). Approximately 0.51 acres of the site drains to the north. (Basin Pl) The remainder of the site drains to the southwest. (Basin P2) All existing runoff is un-concentrated and there is no natural or man-made stormwater conveyance immediately downstream of the site. The existing house onsite will remain on proposed lot 2 although the other existing structures will be removed. All four lots will take access from Morris Avenue So. For the purpose of analysis the total impervious surface is assumed to be 0.40 ac., an increase of 0.26 ac. above existing conditions. It is also assumed that no frontage improvements are required because the development proposal was reduced from five lots to four. This project is subject to the design standards of the 1990 King County Surface Water Design Manual. The Core and Special requirements of this manual are addressed as follows: Core Requirement # 1: Discharge at the natural location. The majority of the site drains to the north as noted above. It appears that most of the on-concentrated runoff from the site finds it's way to Morris Avenue South and is conveyed to the north and/or east. In either case, this site is within the Black River drainage basin. The closest adequate conveyance system is located at the intersection of Morris Avenue So. and South 17ili St. It is proposed that post-developed runoff from the site be directed to this public storm drain. A description of the system downstream of this point can be found in Section III. of this report. Core Requirement# 2: Offsite analysis Level 1 analysis is provided in Section III. of this report. Core Requirement # 3: Runoff control This project appears to be exempt from runoff control and bio-filtration. See Section IV. of this report for analysis and justification. Core Requirement# 4: Conveyance system See Section V. of this report for a conveyance system analysis Core Requirement# 5: Temporary erosion and sedimentation control See Section IX. of this report for a response to the eleven elements of this requirement. Of the Special requirements of the Drainage Manual, only Requirements# 11&12 apply to this project. These are addressed in Section VI. Of this report. Page 1 of 2 King County Building and Land Development Division TECHNICAL INFORMATION REPORT (TIR) WORKSHEET PART 3 TYPE OF PERMIT APPLICATION D Subdivision [);6 Short Subdivision D Grading D Commercial D Other PART 2 PROJECT LOCATION , AND DESCRIPTION ProjectNamei/aLvc!;.N'l;fZ J'd,;.,-JLt7 Location Township 2! Range S" Section _ _,/'--'-'I ___ _ Project Size d, 6 ~ AC Upstream Drainage Basin Size ____ AC PART 4 OTHER PERMITS D DOF/GHPA D Shoreline Management D COE404 D Rockery D DOE Dam Safety D Structural Vaults D FEMA Floodplain D Other D COE Wetlands D HPA l#\41lUiil·iillPii!1i!ilii·l·hlliltAHfiil= Community Drainage Basin -------"',!J.=~=A~C-=-"'='--------'&('---=-'...:--=;..e:=~'----------------------- PART 6 SITE CHARACTERISTICS D River D Stream D Critical Stream Reach D Depressions/Swales D Lake D Steep Slopes D Lakeside/Erosion Hazard PART7 SOILS . Soil Type Bff.AVS,r£ Slo~s ., ~<? D Additional Sheets Attatched CJ D ----·' ~ LJ r--1 -· D Floodplain Wetlands Seeps/Springs High Groundwa!erTable Groundwater Recharge Other Erosion Potential S<-;a.t(t: FIGURE 1 Erosive Velocities 1/90 Page 2 of 2 King County Building and Land Development Division TECHNICAL INFORMATION REPORT (TIR) WORKSHEET PART 8 DEVELOPMENT LIMITATIONS REFERENCE LIMITATION/SITE CONSTRAINT D Ch. 4 -Downstream Analysis D D D D D D Additional Sheets Attatched PART 9 ESC REQUIREMENTS MINIMUM ESC REQUIREMENTS DURING CONSTRUCTION D Sedimentation Facilities @ Stabilized Construction Entrance 5!l Perimeter Runoff Control D Clearing and Grading Restrictions [)!I Cover Practices [)ZJ Construction Sequence D Other PART 10 SURFACE WATER SYSTEM D Grass Lined Channel ~ Pipe System D Tank D Vault D Open Channel D DryPond D WetPond D Energy Dissapator D Wetland D Stream Brief Description of System Operation Facility Related Site Limitalions Reference Facility Limttation PART 11 STRUCTURAL ANALYSIS 1K] [X] ~ D D (May require special structural review) · D Cast in Place Vault D Other D Retaining Wall D Rockery> 4' High D Structural on Steep Slope MINIMUM ESC REQUIREMENTS FOLLOWING CONSTRUCTION Stabilize Exposed Surfaoe Remove and Restore Temporary ESC Facilities Clean and Remove All Silt and Debris Ensure Operation of Permanent Facilities Flag Limits of NGPES Other D Infiltration D Depression D Flow Dispersal D Walver D Regional Detention .S/.v/3-t!)v7:S Method of Analysis 5Bt?t/ef &7/0,.;A:l. Compensation/Mitigation of Eliminated Site Storage D Additional Sheets Attatched PART 12 EASEMENTS/TRACTS D Drainage Easement D Access Easement D Native Growth Protection Easement D Tract D Other I or a civil engineer under my supe,vision have visited the site. Actual site conditions as observed were incorporated into this worksheet and the attatchments. To the best of my knowledge the information provided here is accurate. . FIGURE 1 -CONTINUED----------___J ISO ~DELORME ! 1 )} / ,I ~ (!' ~' . S.tSIHs1/ :.i ' " 'la "' \ 7 \ \ ·, ~ \ \ ·, \ : 167 Data use subject to license. c:i 2004 Delorme. Topo USA® 5.0. www.delorme.com ' \\, \ \ % \ \ s:1.9.114 S.T ---------,_. > ,, ., ,' .'/ S 2CLTH -~--:-:;" / / / D ~ * I~ Ml<{H.4·EJ FIGURE 2 Topo USA® 5.0 ---- .~ I --. --- / ( i Scale 1 : 6,00~~-------~ "'2 .... '3S ,wt i 1" = 500.0 ft ·, ~ --==---Data Zoom 15-0 \ l / Pt 1- """"" HCU![ (To RDWN) fF • 172.11 I TBR I ;. CARA.GE I • I I I L __ ~ MacLearnsberry Engineering, P .S. Civil Engineers o f!anoers 159 Wyatt Way NE painhri,lg~ I.Janel, WA 98110 pl,one, (206) 84207716 . ~,Jm;J~, (206) 780-2408 r i U) w ~ U) 0::: S. 17TH ss--S. 18TH S FIGURE 3A Paul Houvener Houvener Short Subdivision Pre-Developed Conditions DRAWN BY CAH 1111 26528 MCM 1• m 40• HET / \ MacLearnsberry Engineering, P .S. Civil Engineers ~ Planners 159 Wyatt Way NE l;lamkidge I.land, WA 98110 photte, (206) 842~7716 fu.Jmil., (206) 780-2408 r f Cl) w ~ Cl) c::: S. 17T ~-S. 18TH FIGURE 38 Paul Houvener Houvener Short Subdivision Develo ed Conditions """"' BY CAH o,,. January 23, 2007 MCM 1· • 401 "Tl ci C ;:o m .i:,. ·t· USDA Nabanl Resources iliiliill r.enanation Senke a SOIL SURVEY OF KING COL ... ( AREA, WASHINGTON 50 100 Houvener-Renton Meters 200 Web Soil Survey I. 1 National Cooperative Soil Swvcy 0 150 300 600 900 Feet 1,200 7/19/2006 Page 1 of3 Soil Survey of King County Area. Washington Map Unit Legend Summary King County Area, Washington Map Unit Symbol ·--AgD BeC BeD Ur Map Unit Name Acres in AO! Alderwood gravelly sandy 12.0 loam, 15 to 30 percent slopes Beausite gravelly sandy loam, 6 88.6 to 15 percent slopes Beausite gravelly sandy loam, 8.3 15 to 30 percent slopes Urban land 0.9 Web Soil Survey 1.1 National Cooperative Soil Survey Percent of AO! 10.9 80.7 7.6 0.8 Houvener-Renton 7/1912006 Page 3 of3 lJSOA NIMand Resource1 alilli f.4.lltlerratiob Sent« SOIL SURVEY OF KING ~~UNTY AREA, WASHINGTON MAP LEGEND Soll Map Units e Citle1 c:::::J Oelalled Counties c:::::J Detailed States Interstate Highways Roads -+--+-Ralls \l\llter Hydrography Oceans >. f >.,A, A¥ Escarpment, bedrock vAv,w,-,,.v-. Escarpment, nan-bedrock ~,.-, ,,,,', Gulley 111111111111111 Levee Slope " Blowout 0 Borrow Pit • Clay Spot • Depression, dosed Eroded Spot X Gravel Pit GraveHy Spot ~-Gulley A. Lava Flow @ Landfill .. Marsh or Swamp ® Miscellemeous 1/!Jater V Rock Outcrop + Saline Spot Sandy Spot !> Slide or Slip 0 Sinkhole pl Sodlc Spot .. SpoUArea 0 Stony Spot Ill vert Stet @ Perennial Water t VVl!t Spot Houvener-Renton MAP INFORMATION Source of Map: Natural Resources Conservation Service Web Soil Survey URL: http://websoilsurvey.nrcs.usda.gov Coordinate System: UTM Zone 10 Soil Survey Area: King County Area, Washington Spatial Version of Data: 1 Soil Map Compilation Scale: 1 :24000 Map comprised of aerial images photographed on these dates: 7/10/1990; 7/16/1990 The orthophoto or other base map on which the soil lines were compiled and digitized probably differs from the background imagery displayed on these maps. As a result, so_me_minor shifting of map unit boundaries may be evident. Web Soil Survey 1.1 National Cooperative Soil Survey 7/19/2006 Page 2 of3 ~-- KING COUNTY, WASHINGTON, SURFACE WATER DES I G N MANUAL (2) CN values can be area weighted when they apply to pervious areas of similar CN's (within 20 CN points). However, high CN areas should not be combined with low CN areas (unless the low CN areas are less than 15% of the subbasin). In this case, separate hydrographs should be generated and summed to form one hydrograph. FlGURE ).5.2A HYDROLOGIC SOIL GROUP OF THE SOILS IN KING COUNTY HYDROLOGIC HYDROLOGIC SOIL GROUP GROUP* SOIL GROUP GROUP* Alderwood C Orcas Peat D Arents, Alderwood Material C Oridia D Arents, Everett Material t{-+ Ovall C Beausite Pilchuck C Bellingham I U' Puget D Briscot D Puyallup B Buckley D Ragnar B Coastal Beaches Variable Renlon D Earlmont Silt Loam D Riverv.rash Variable Edgewick C Salal C Everett A/8 "Sammamish D Indianola A Seattle D Kitsap C Shacar D Klaus C Si Silt C Mixed Alluvial Land Variable Snohomish D Neilton A Sultan C Newberg B Tukwila D Nooksack C Urban Variable Normal Sandy Loam D Woodinville D HYDROLOGIC SOIL GROUP CLASSIFICATIONS A. (Low runoff potential). Soils having high infiltration rates, even when thoroughly wetted, and consisting chiefly of deep, well-to-excessively drained sands or gravels. These soils have a high rate of water transmission. B. c. D. • (Moderately low runoff potential). Soils having moderate infiltration rates when thoroughly wetted, and consisting chiefly of moderately fine to moderately coarse textures. These sons have a moderate rate of water transmission. {Moderately high runoff potential). Soils having slow infiltration rates when thoroughly wetted, and consisting chiefly of soils with a layer that impedes downward movement of water, or soils with moderately fine to fine textures. These soils have a slow rate of water transmission. (High runoff potential). Soils having very slow infiltration rates when thoroughly wetted and consisting chiefly of clay soils with a high swelling potential, soils with a permanent high water table, sons wtth a hardpan or clay layer at or near the surface, and shallow soils over nearly impervious material. These sons have a very slow rate of water transmission . From SCS, TR-55, Second Edttion, June 1986, Exhib~ A-1. Revisions made from SCS, Soil Interpretation Record, Form #5, September 1988. 3.5.2-2 11/92 "'''' ... ,.,,, E.(J"l'RO'. "' \ SCALE• I 1/ --./ I I \ I t- 1 '' ~ ~o; """"' ll.J'¥,Q: 00<:.RETMIN. WALLIS 0.4'5.0""1(1'1.1£ ""'"" QJ'W[Ell'.N:,/U.lff,C .,.,_. Cl6'S.CF"11Pll£ I )5,385 '?Q.rt FIGURE 5 .. ! "' ~-17TH ~- J"i UJ > ;1 ~I 2 I -- ~ I I I I _,,_ £ .. IS\K-a"RCP,"E £•$»-a"RD>,SN ss-~. 18TH ~T. Section II. Preliminary Conditions Summary II.) Preliminary Conditions Summary Memorandum from Mike Dotson to Jill Hall dated August 9, 2005 Water 1. There is an 8" waterline in Morris Ave South. Response: Informational comment -Acknowledged 2. The modeled fire flow available at the site is approximately 1000 gpm. Static water pressure is approximately 60psi. Response : Informational comment -Acknowledged 3. The proposed project is located within the 300-water pressure zone Response : Informational comment -Acknowledged 4. If fire sprinkler systems are necessary, then a separate fire sprinkler permit will be required. Response: Informational comment -Acknowledged. We do not anticipate the need for sprinkler systems. 5. All new single-family construction must have a fire hydrant capable of delivering a minimum of 1000 gpm. (home square footage less than 3600) and must be located within 300 feet of the structures. There may be some hydrant(s) that meets this requirement. However, any existing sub-standard hydrants will need to be replaced and/or retrofitted with a quick disconnect Storz fittings. Response : Existing fire hydrants are located on the east side of Morris Ave South to the north and south of the site. The new structures will be within 300 feet of these hydrants. A note has been included on the plan advising the possible need for replacement and/or retrofitting. 6. If the home square footage is greater than 3600, then minimum fire flow increases to 1500 gpm, and additional hydrants may be required. A Water System development Charge of $1,525.00 per new lot is due at time of issuance of a construction. Response : A new hydrant is shown between lots 1 and 2 with a note addressing this issue. 7. All short plats shall provide a separate water service to each building lot prior to recording of the short plat. Response : Separate services are shown on the plan with a note addressing this issue. Sanitary Sewer 1. There is an existing 8-inch sewer main in Morris Ave. South. Response : Informational comment -Acknowledged 2. Our records indicate that the existing home at 1719 Morris Ave. South is currently connected to the sewer system (see attached side-sewer card). The sewer stub may be reused if it is in adequate condition and location to serve one new home. Response : The existing house will remain and continue to use this service. 3. All short plats shall provide separate side sewer stubs to each building lot prior to recording of the short plat. No dual side sewers are allowed. Side sewers shall be a minimum 2% slope. Response : Separate side sewers are shown on the plan with notes addressing this issue. 4. The sanitary Sewer System Development Charges (SDC is $900 per single-family home. This fee is due at the time of utility construction permit. Response : Informational comment -Acknowledged. Also, a note addressing this issue is included on the plan. Surface Water 1. This site drains to the Black River drainage basin Response : Informational comment -Acknowledged 2. A drainage analysis and design is required to comply with the requirements and standards of the 1990 King County Surface Water design manual. Response : A Technical Information Report is included with this submittal. The proposed design is in compliance with the standards. 3. The preferred method of drainage control would be infiltration facilities. Response: Infiltration is not feasible on this site.(see enclosed geotechnical report. This project is exempt from flow control and water quality treatment. Perforated stub-outs are proposed on the plan. Justification for the proposal is provided in Section N. of the T.I.R. 4. The Surface Water System Development Charges (SDC) is $715 per lot. This fee is due at the time the utility construction permit is issued. Response : Informational comment -Acknowledged. A noted is included on the plan addressing this issue. Street Improvements 1. Transportation Mitigation fees are $75 per additional generated trip generated. These fees shall be assessed per new single-family home at a rate of9.57 trips. Response : Informational comment -Acknowledged. A note is included on the plan addressing this issue. 2. All wire utilities shall be installed underground per the City of Renton Under- grounding Ordinance. If three or more poles are required to be moved by the development design, all existing overhead utilities shall be placed underground. Response : Informational comment -Acknowledged. A note is included on the plan addressing this issue. 3. According to City of Renton code, projects that are 5 residential lots in size are required to install half pavement v.,idth per standards. This project requires installing curb, gutter, sidewalks, and street lights along Morris Ave. South. A deferral of these improvements may be requested through the Board of Public Works. Response : The development proposal has been changed from 5 lots to 4 lots. Frontage improvements are no longer required. General Comments l. Permit application will require separate plan submittals for all proposed utility, drainage and street improvements. Plans are required to be prepared by a licensed Civil Engineer according to City of Renton drafting standards. Response : Separate plans are provided and prepared by a licensed Civil Engineer. 2. Permit application must also include an estimated cost of construction for water, sewer and roadway/drainage improvements (please see permit application available at 6th floor Customer Service Counter). Separate permits for water meters, and side sewers are required. And a separate utility permit to cut and cap existing utilities to existing structures on site will be required as part of the demolition permit. Response : See T.I.R. Section X. for cost estimates. Other permits will be applied for as required. 3. The applicant is responsible for securing any private utility easements. Response : No private utility easements are required for this project. Jill Hall Associate Planner City of Renton Development Services Division 1055 South Grady Way, Renton, WA 98055 RE: Houvener Short Plat, Pre-App file no. 05-100 In response to the memorandum from Jill Hall dated August 11, 2005 regarding Pre- Application file no. 05-100 Land Planning Northwest is offering the following information: The proposed short plat has been revised to show 4 lots. This meets current density requirements for the R-8 zone in which the project lies. All access panhandles have been deducted from gross lot area in order to calculate net density of the proposed project. Minimum lot size, width and depth for the R-8 zone have been met. The minimum lot size of the proposed project is 5,085 net square feet. All lots are at least 65 feet deep and at least 50 feet wide. Gross and net square footage for all lots is provided on the site plan. Building Height and lot coverage shall be within the limits for the R-8 zone. The required minimum building setbacks are shown on the site plan for the proposed project. All lots shall provide parking for at least two vehicles in driveway and/or garage spots. Panhandles to lots 3 and 4 are private, and provide access to one lot only. Minimum width of20 feet is shown on the site plan. All addresses shall be visible from Morris Ave at the time of construction. The maximum driveway grade shall not be exceeded for the proposed project. See grading plans. A 5-foot wide landscaped strip is shown along Morris Ave in the front yards of lots 1 and 2. Planting in this strip shall meet RMC, and is shown on the conceptual landscape plan. In addition, at least two trees of a minimum caliper of 1.5" shall be planted in the front yard of all new lots. A Geotechnical report and coal mine hazard letter has been prepared and is included in this submittal. This proposed project is consistent with the Residential Single Family (RSF) Comprehensive Plan Land Use Designation. The application fee shall be paid at the time of formal land use application. All other fees shall be paid at their respective required payment dates prior to recording. Please do not hesitate to contact us if you have questions or comments. Thank.you, Andy McAndrews Associate Planner/Project Manager Land Planning Northwest Phone: (206) 719-7901 Fax: (425) 640-8562 Lpnw@verizon.net Section Ill. Offsite Analysis III.) Offsite Analysis Field inspection was conducted on July 28, 2006. Weather conditions consisted of clear skies and temperatures in the low 80's. The existing stormwater conveyance system along South 17th Street and Talbot Rd. South was walked for approximately V. mile from the site to Williams Ave. South. This system consists of a network of catch basins and 12-inch diameter concrete pipes for the entire length. Exhibit "B" illustrates the alignment of the system and the contributing drainage basin. Photos were taken to illustrate the surface features present. No evidence of overtopping or erosion was noted. As can be seen in the photos, there is no curb and gutter along the entire route limiting collection of surface-water runoff. This does not limit the capacity of the system to convey up-stream flows. .-=::,:---------------9 3~0f)l.:I 6l(S' 0 N 'Z/1 3: 3:S"ll Nf'ZJ.. 61 fD 009'1"'l 002 -E-lZ ( ~; .. -at"Lil ~~a b ,,/'' \~p ,; -n 11861 <IA Y.N -'I(( -O'l.., S'O qua>1ll DUQ1IOO ~·-':.7' ··tr~~~ I I -,~·t:a·" ~~M-~j- i11 a as I£'ZJ. 81 -£.i 90/8Vto SE>IA llllS 'IVOINHO!LI. /4cl/&/ d m~isAs m.10:is • \\ \ '!: I '\ ·: l"·'-"·,' , I; , \ . \ \ '\. ·~ :o\1 ·rr .. i. ,: J j •-t-B3'~ 1, t-L3'ta ,_ I lo-93'la ~ .. -9l'la -1 6"'3'ta · " i t-93'1 I a-m V ,_,,, -- • fi/ '/! ,"/,; 0 F ~ ,-"' ,.\_/ '; ·. I ' \. \ )i 9-.. 3'1.r " {~' ~j,·1-a3'9T i£.-.8l'91 / 8 • ..... \0 ~ tJ ~ z := 1.11 t'l':I ~ ,_,. ' tJ SEISMIC HAZARD AREAS Technical SeNlces Plannln9'Bufk:llng/Public Works R. MacOnle, D. Visneskl September 2005 -----City Limits Ill H~h Hazaro FLOOD HAZARD AREAS 0 3000 -----Oty l.mh 6000 Technical Services Plannln!)'Bulldlng/Publlc WOfks R. MaCOnle, D. Vlsflesld Sep!embef 2005 COAL MINE HAZARD AREAS e Technlcal Services Plam""""-'""""W<xk, R. MacClnie, 0. Vlsn19$kl July 2005 . .... """' -----City Limits -High Hazard -Moderale IBllll!I! Unclassified ! ""i ,, .!I ' . ' ~T"'.""ti/;--=-"-~! ' ·:-,:- --· -;,.:; I --·~!:~~; ---------_: • '·1 I ~----' I I I I I ·f -~ AQUIFER PROTECTION ZONES e Tedmical---R. MacOnie, o. Vlsneskl --Renton Munldpal Code --, @~%5.l Zone l Modified [''-·-:·:·-·_--;-j ZoneZ ----=--=-=.. City Ll!rils EROSION HAZARD AREAS e Technical SeMCSS Plannlng/Bulldlfl1J'Publlc Wort<:s R. MaCOnle, D. vtsneskl September 2005 -----CJty Limits 0 15<10 3000 l~:3000' LO.KE WASHINGTON 1014-'-----1--,---l.+,e..lO~, \ LANDSLIDE HAZARD AREAS • Kinu c-ty Hmo.-d -----Qyl>nlt, DOWNSTREAM PHOTOS Looking south along Morris Ave . Note lack of drainage conveyance along site frontage at left in photo ~ Looking west along north line of site Runoff from majority of site appears to sheet flow into adjacent driveway and then drains to Morris Ave . ' Catch basin at southeast comer of intersection of Morris Ave. and S 17th St. Storm drain runs east from this point CB and storm drain along south side of S 17th St. Note that little runoff from road is intercepted CB and storm drain at SW comer of intersection of S 17th St. and Talbot Rd. S CB's and storm drain at intersection of Talbot Rd. S and S 16th St.-looking north CB in Williams Ave S just north of intersection with Talbot Rd. S approx. 1/4 mile downstream of site. Cover could not be opened to verify pipe alignment. flows appear to be towards the north beyond this point Section IV. Retention I Detention Analysis and Design IV.) Retention/Detention Analysis and Design Existing Site Hydrology (Part A) Basin Pl Pervious area= 0.41 acres CN value= 81 ( This is a conservative estimate assuming second growth forest) Tc = 18.82 min. Impervious area= 0.10 acres CNvalue = 98 Tc= 5.00 (assumed) Q2 = 0.07 cfs. Q10= 0.14cfs. Q100 = 0.23 cfs. BasinP2 Pervious area = 0.11 acres CN value= 81 (see above) Tc= 13.00 min. Q2 = 0.01 cfs. Q10 = 0.02 cfs. Q100 = 0.04 cfs. Developed Site Hydrology (Part B) Basin DEV Pervious area= 0.26 acres CN value= 86 (lawn assumes) Tc = 5.00 min. (assumed) Impervious area= 0.36 acres (Portion subject to vehicular traffic= 3840 sf.) CNvalue=98 Tc= 5.00 min. (assumed) Q2 = 0.19 cfs. Q10 = 0.31 cfs. Q100 = 0.44 cfs. Hydrologic Analysis (Part C) The enclosed analysis was performed using the Santa Barbara Urban Hydrograph Method. Computer software entitled "Waterworks 4.13" as prepared by Engenious Systems Inc. was used. For the purpose of evaluating the need for on-site peak rate runoff control, the runoff rates for basins Pl and DEV (listed above) were compared. The increase in runoff due to development during a 100yr.-24hr. storm event was calculated to be 0.21 cfs. This is less than the 0.50 cfs. threshold identified on Section 1.2.3 -Core Requirement# 3. Consequently, this project is exempt from the requirement for runoff control. In addition. this project will construct less than 5000 sf. of impervious surface subject to vehicular use or storage of chemicals. Consequently, this project is also exempt from the requirement for bio-filtration facilities. Retention/Detention System (Part D) Retention/detention facilities do not apply to this project due to it's exemption status. The site has been evaluated for the potential of roof downspout infiltration systems. The underlying soils were found to be inadequate for this purpose. The proposed lots are also too small to allow for the installation of dispersal systems. Consequently, perforated stub- outs designed in conformance with Figure 4.5.6B are proposed for this project. These will direct runoff to the nearest adequate conveyance system located at the intersection of Morris Ave. South and South 17th Street. K I N G C O U N T Y, W A S H I N G T O N. S U R F A C E W A T E R D E S I G N M A N U A L I I FIGURE 3.5.lC 2-YEAR 24-HOUR IS0PLUV1ALS \-----\'--t4t::i!til-"ai1t I ,\ l"f----- lf ......__ ~ lfl-~~~A~ 11 111 ltf ,/ I / -YEAR 24-HOUR PRECIPITATION ,3.4-ISOPLUVIALS OF 2-YEAR 24-HOUR TOTAL PRECIPITATION IN INCHES 0 l 2 3 4 5 6 7· B Mlt.s 1: 300,000 1/90 K I N G C O U N T Y, W A S H I N G T O N, S U R F A C E W A T E R D E S I G N M A N U A L 2.1 2.2 <3 2.4 25 2.6 2.? 2.s 2.9 3.0 -YEAR 24-HOUR PRECIPITATION / , 3.4-ISOPLUVIALS OF 10-YEAR 24-HOUR TOTAL PRECIPITATION IN INCHES 0 1 2 3 4 5 6 7 8 MIies I: 300,000 1/90 ( 4.0 K I N G C O U N T Y, W A S H I N G T O N, S U R F A C E W A T E R D E S I G N M A N U A L __ GURE 3.5.lH 100-YEAR 24-HOUR ISOPLUVIALS 11 EAR 24-HOUR PRECIPITATION 3.4 -ISOPLUVIALS OF 100-YEAR 24-HOUR TOTAL PRECIPITATION IN INCHES 0 1 2 3 4 5 6 7 8 MIies l: 300,000 r'""-'-__ 6.5 -r-"'--., 6D 5Jf"" 1/90 KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL FIGURE 4.5.6B PERFORATED S'IUB-OUT DESIGN RANDOM FILL TRENCH X-SECTION PLAN VIEW OF ROOF NOTE: NOT TO SCALE 4.5.6-4 FILTER FABRIC 4" PERF PIPE 1 /t' -t" WASHED ROCK SLOPE ---1•- 2' X 10' CH ----LEVEL TREN TO ROAD DRAINAGE SYSTEM T W/PE RF PIPE 11/94 1/19/07 10:24:32 am Shareware Release HOUVENER SHORT PLAT page 1 ================------=----===-----:---=----------------------=====-- BASIN ID: DEV SBUH METHODOLOGY TOTAL AREA •...... : RAINFALL TYPE .... : PRECIPITATION .... : TIME INTERVAL .•.• : BASIN SUMMARY NAME: 2YR 24HR 0.62 Acres TYPElA 2.00 inches 10.00 min BASEFLOWS: AREA, , : CN .•.. : TC .... : 0.00 cfs PERV 0.26 Acres 86.00 5.00 min ABSTRACTION COEFF: 0.20 TcReach -Sheet L: 130.00 PEAK RATE: 0.19 cfs VOL: ns:0.1500 p2yr: 2.00 s:0.0300 0.07 Ac-ft TIME: 480 min BASIN ID: Pl SBUH METHODOLOGY TOTAL AREA .•••..• : RAINFALL TYPE .... : PRECIPITATION .... : TIME INTERVAL .... : NAME: 2YR 24HR 0.51 Acres TYPElA 2.00 inches 10.00 min BASEFLOWS: AREA .. : CN .... : TC .... : 0.00 cfs PERV 0.41 Acres 81.00 18.82 min ABSTRACTION COEFF: 0.20 TcReach -Sheet L: 250.00 PEAK RATE: 0.07 cfs VOL: ns:0.1500 p2yr: 2.00 s:0.0440 0.04 Ac-ft TIME: 480 min BASIN ID: P2 NAME: 2YR 24HR SBUH METHODOLOGY TOTAL AREA ....••. : RAINFALL TYPE .... : PRECIPITATION .... : TIME INTERVAL ...• : 0.11 Acres TYPElA 2.00 inches 10.00 min ABSTRACTION COEFF: 0.20 BASEFLOWS: AREA .. : CN .... : TC ..•. : o.oo cfs PERV 0.11 Acres 81.00 13.00 min TcReach -Sheet L: 130.00 ns:0.1500 p2yr: 2.00 s:0.0300 PEAK RATE: 0.01 cfs VOL: 0.01 Ac-ft TIME: 480 min IMP 0.36 Acres 98.00 5.00 min IMP 0.10 Acres 98,00 5.00 min IMP 0.00 Acres 0.00 0.00 min 1/19/07 10:25:8 am Shareware Release HOUVENER SHORT PLAT page 1 ========================----=--======-===--------=--=-====-----~===== BASIN ID: DEV SBUH METHODOLOGY TOTAL AREA •...... : RAINFALL TYPE ..•. : PRECIPITATION ..•. : TIME INTERVAL .... : BASIN SUMMARY NAME: lOYR 24HR 0.62 Acres TYPElA 2.90 inches 10.00 min BASEFLOWS: AREA •• : CN ..... : TC •••• : 0.00 cfs PERV 0.26 Acres 86.00 5.00 min ABSTRACTION COEFF: 0.20 TcReach -Sheet L: 130.00 PEAK RATE: 0.31 cfs VOL: ns:0.1500 p2yr: 2.00 s:0.0300 0.11 Ac-ft TIME: 480 min BASIN ID: Pl NAME: lOYR 24HR SBUH METHODOLOGY TOTAL AREA ...••.. : 0.51 Acres BASEFLOWS: 0.00 cfs RAINFALL TYPE ..•. : TYPElA PERV PRECIPITATION .•.• : 2.90 inches AREA .. : 0.41 Acres TIME INTERVAL .... : 10.00 min CN ..... : 81.00 TC ..... : 18.82 min ABSTRACTION COEFF: 0.20 TcReach -Sheet L: 250.00 PEAK RATE: 0.14 cfs VOL: ns:0.1500 p2yr: 2.00 s:0.0440 0.06 Ac-ft TIME: 480 min BASIN ID: P2 NAME: lOYR 24HR SBUH METHODOLOGY TOTAL AREA ....•.. : 0,11 Acres BASEFLOWS: 0.00 cfs RAINFALL TYPE ..•• : TYPElA PERV PRECIPITATION •.•. : 2.90 inches AREA .• : 0.11 Acres TIME INTERVAL .... : 10.00 min CN ..... : 81.00 TC .... : 13.00 min ABSTRACTION COEFF: 0.20 TcReach -Sheet L: 130.00 ns:0.1500 p2yr: 2.00 s:0.0300 PEAK RATE: 0.02 cfs VOL: 0.01 Ac-ft TIME: 480 min IMP 0.36 Acres 98.00 5.00 min IMP 0.10 Acres 98.00 5.00 min IMP 0.00 Acres 0.00 0.00 min 1/19/07 10:23:45 am Shareware Release HOUVENER SHORT PLAT page 1 ==================-======================---=---====;================ BASIN ID: DEV SBUH METHODOLOGY TOTAL AREA ....... : RAINFALL TYPE .... : PRECIPITATION .... : TIME INTERVAL .... : BASIN SUMMARY NAME: lOOYR 24HR 0.62 Acres TYPElA 3.90 inches 10.00 min BASEFLOWS: AREA .. : CN •.... : TC .•.. : 0.00 cfs PERV 0.26 Acres 86 .00 5.00 min ABSTRACTION COEFF: 0.20 TcReach -Sheet L: 130.00 PEAK RATE: 0.44 cfs VOL: ns:0.1500 p2yr: 2.00 s:0.0300 0.16 Ac-ft TIME: 480 min BASIN ID: Pl SBUH METHODOLOGY TOTAL AREA .•...•. : RAINFALL TYPE .... : PRECIPITATION .... : TIME INTERVAL .... : NAME: lOOYR 24HR 0.51 Acres TYPElA 3.90 inches 10.00 min BASEFLOWS: AREA .. : CN •••• : TC ••.• : 0.00 cfs PERV 0.41 Acres 81.00 18.82 min ABSTRACTION COEFF: 0.20 TcReach -Sheet L: 250.00 PEAK RATE: 0.23 cfs VOL: ns:0.1500 p2yr: 2.00 s:0.0440 0.10 Ac-ft TIME: 480 min BASIN ID: P2 NAME: lOOYR 24HR SBUH METHODOLOGY TOTAL AREA ..•.... : 0.11 Acres BASEFLOWS: 0.00 cfs RAINFALL TYPE .... : TYPElA PERV PRECIPITATION .... : 3.90 inches AREA .. : 0.11 Acres TIME INTERVAL .... : 10.00 min CN ..•. : 81.00 TC .... : 13.00 min ABSTRACTION COEFF: 0.20 TcReach -Sheet L: 130.00 ns:0.1500 p2yr: 2.00 s:0.0300 PEAK RATE: 0.04 cfs VOL: 0.02 Ac-ft TIME: 480 min IMP 0.36 Acres 98.00 5.00 min IMP 0.10 Acres 98.00 5.00 min IMP o.oo Acres 0.00 0.00 min Section V. Conveyance System Analysis and Design I le I I I I I I I ·-I I I I I I I I II V. Conveyance System Analysis and Design The stormwater conveyance system for this project is limited to the roof downspout collection system and short section (two pipe runs) of offsite stonn drain to be constructed in Morris Ave. South. The low flows anticipated do not warrant an extensive analysis. The following analysis uses the Rational method to conservatively estimate I OOyr. peak flows and the proposed pipes are evaluated for full flow capacity relative to the entire contributing basin. Rational Method Check Due to the small size of the contributing basin, the post-developed 1 OOyr. flow rate will be calculated using the rational method. To simplify this analysis, the lOOyr. flow for the entire basin will be compared to most restrictive pipe runs to demonstrate capacity. Q=CIA A = 0.62 acres C = (0.26} (0.25} + (0.36} (0.90} 0.62 I= (P10o)(iR) Tc= 10 minutes (assumed) = 0.63 (-0.63) P 100 -3 .90 inches (-bR) iR = (aR) (Tc) = (2.61)(10) = 0.61 I= (3.90) (0.61) = 2.38 Qtoo = (0.61) (2.38)(0.62) = 0.90 cfs. Minimum design slope-12" pipe= 0.50% (CBI to Ex.) n = 0.012 Per Manning's eq.: Qru11 = 2.73 cfs. > 0.90cfs. OK Minimum design slope-6" pipe= 4.20 % ( YD4 to YDl), n = 0.012 Per Manning's eq. : Q1u11 = 1.25 cfs. > 0.90 cfs. OK 3.2.1 RATIONALMETHOD General Land Covers Single Family Residential Areas· Land Cover· C Land Cover Density C Dense forest 0.10 0.20 DU/GA (1 unit per 5 ac.) 0.17 Light forest 0.15 0.40 DU/GA (1 unit per 2.5 ac.) 0.20 Pasture ~ 0.80 DU/GA (1 unit per 1.25 ac.) 0.27 Lawns 5 1.00 DU/GA 0.30 Playgrounds 030 1.SODU/GA 0.33 Gravel areas 0.80 2.00 DU/GA 0.36 Pavement and roofs I 0.90 I 2.50 DU/GA 0.39 Open water (pond, 3.00 DU/GA 0.42 1.00 lakes, wetiands) 3.50 DU/GA 0.45 4.00 DU/GA 0.48 4.50 DU/GA 0.51 5.00 DU/GA 0.54 5.50 DU/GA 0.57 6.00 DU/GA 0.60 Based on average 2,500 square feet per lot of impervious coverage. For combinations of land covers ljsted above, an area-weighted "CcCx A," sum should be computed based on the equation C.-x A,= (C, x A,)+ (C2 x A2 ) + ... +(C. x A.). where A,= (A 1 + A2 + ... +A.), the total drainage basin area. Design Storm Return Frequency aR 2 years 1.58 5 years 2.33 10 years 2.44 25 years 2.66 50 years 2.75 100 years 2.61 . --"£~::i~\7r·.,-.. .. . · TABLE 3.2.I;C J:_. V AL~R T, USING THE RATIONAL METHOD · '-":l''l"t'Cie:f~c Land Cover Category Forest with heavy ground litter and meadow Fallow or minimum tillage cultivation Short grass pasture and lawns Nearly bare ground Grassed waterway Paved area (sheet flow) and shallow gutter flow 1998 Surface Water Design Manual 3.13 2.5 4.7 7.0 10.1 15.0 20.0 bR 0.58 0.63 0.64 0.65 0.65 0.63 9/1198 Section VI. Special Reports and Studies 01/12/2007 10:47 3606536852 January 9, 2007 Project No. KEOS874A Mr. Paul Houvener 100 2• Avenue South Edmonds, Washington 98020 Subject: Geotecimical Evaluation 1719 Morris Avenue South Renton. Washington Mr. Houvener: LPNW This letter-report p,:esems the resullS of Associated Earth Scie:oces, Inc. 's (AESl's) subsurface e;11ploralion and geot.echnical assessment for the property located at 1719 Morris Avenue South in Renton, Washington (Figure 1). The approximate locations of the explorations accomplished for this study ar:e p(eSC!lted on the Site and Exploration Plan, Figure 2. If any changes in the nature, design, or location of the structure are planned, the conclusions and recommendations in this letter-report should be reviewed and modified, or verified, as necessary. The purpose of this evaluation was to provide subsurface data and design recommendations for the on-site infiltration of stonn water and g,:neral geotec:hnical recommendations reguding site development. This evaluation included a review of available geologic: literature, excavation of exploration pits, drilliDg hand-auger borings, and performing geologic studies 10 assess the type, thickness, distribution and physical properties of the subsurface sediments and shallow ground water conditions. A previous report prepared by AESI, dated January 27, 2006, addressed !he poumtilll Coal Mine Hazard for the subject site. Written authoruation to proceed with this evaluation was granted by Mr. Paul Houvener. Our study was accomplished in general accordance with Olll' proposal dated August 7, 2006. This letter-report bas been prepared for the exclusive use of Mr. Paul Houvener and his agents for specific application to this project. Within the limitations of scope, schedule, and budget, our services have been performed in accordance with generally accepa:d geotecbnical engineering and engineeting geology praclic:es in effect in Ibis ue:a at lhe time our report was prepared. No other wauauty, express or Implied, is made. Olll' observations, fiudings, and opinions are a means to ideJJ.tify and n:duce the inherent risks to tbe owner. JCidd>,,dOflia,•,11 Rlil>Aw,-,Suioc lOO •Klddand, WA !l80'3•PI (42.S) IIZl-7/UI • Fl (US)827,SU4 E,amOllia,•2911112 Howia.-.-Soirz:Z•S-,,,WA 9112111 •PI (US)2S!M)522• Fl (<US) 252-3408 .... a <Din PAGE 02 01/12/2007 10:47 3606536852 LPNW PROJECT AND SITE DESCRIPTION This lctteT-report was completed with an understanding of the project based on our discussions with Mr. Larry Deishef of Landplaning Northwest. Present plans call for the development of several single-family, residential building lobi on the 0.6-acre parcel. The parcel is currently occupied by three structures im:luding a house:, detached garage, and an accessory dwelling u.uit. The parce.l is covered with landscape vegetation and grass. Total elevation change across the property was on the order of 4 feet. SUBSURFACE EXPLORATION Our field srudy included ex.cavaliltg three exploration pits and drilliog three band-auger borings to gain infonnation about the site. The various types of sed.imeots, as weU as the depths where characreristics of the sediments changed, are indicated on the exploration logs attached to this letter-report. The depths indicated on the logs where conditions changed may represent gradational variatioDS between sediment types. The conclusions and recommendations presented in this letter-report are based on the six subsurface explorations completc:d for this evaluation. The number, locations, and depths of the e.xplor111ions were completed within site and budgetary constraints. Because of the nature of exploratory work below ground, extrapolation of subsurface conditions beyond field explorations is necessary. Differing subsurface conditions may sometimes be present due to the random nature of deposition and the alteration of topography by past grading and/or filling. The oawrc and extent of any variatioGS between the field Cllplorations may not become fully evident until construction. If variations are obsei:ved at that time, it may be necessary to re- evaluate specific recommendations in this report and make appropriate changes. Exploration pits were excavated with a tractor-mounted backhoe. The pits permitted direct, visual observation of subsurface conditions. Materials encountered in the exploration pits were studied and classified in the field by a geologist from our firm_ Disturbed soil samples were selected from the pits, placed in moisture-tight containers, and transported to our laboratory for further visual classification and testing. Testing was limited to visual-manual classification of the collected samples in general accordance with American Society for Testing and Materials (ASTM) standard practices. After logging the exposed soils, all exploration pits were bacldUled with the excavated soil 1111d lightly tamped with the backhoe bucket. The exploration borings were completed by advancing a 4-incb-diameter, stainless steel hand auger. During drilling, samples were obtained at each change in soil type. Due to the density of the soil and presence of gravel, hand-auger exploration depths were limited to 3 feet or less. The borings were conliuullUSIY observed and logged by a geologist from our firm. 2 PAGE 03 01/12/2007 10:47 3606536852 LPNW SUBSURFACE CONDITIONS Subsurface conditiODS on the parcel were inferred from the subsurface ~lol"3.tioos accomplished for this study, visual recollllllissance of the site, and review of applicable geologic literature. As shown on the exploration logs, the subsurface explorations generally cru:ounten:d dense, fine sand with gravel overlying weathered bedrock. Some of the soil overlying the weathered bedrock is interpreted as fill. The following section presents more derailed subsudace infonnation org•ui:rm from the .~hallowest (youngest) to the deepest (oldest) ft'dimem types. Fill soils (not naturally placed) were encountered in exploration pill! EP-1, EP-2, and EP-3. The fill l'3.llged in thickness from 2 to 5 feet. As noted on the exploration logs, the fill typically consisted of dense, dry, tm to brown, fine sand and silt with trace gravel and cobble_ Some of the material interpreted as fill may be disturbed, natural soils derived from weathering of the underlying bedrock. Fill/disllu:bed soil should also be expected elsewhere on the site, particularly adjacent to existing buildings, buried utilities, aud driveway/landscape afeas. These materials appear to vary in both quality and depth across the site_ Since the quality, thickness, and compaction of the fill materials is low or variable, the fill is comidered umuitable for strucrural support without proper compaction. Natural soils beneath the fill materials, and at the surface where fill materials were absent, consisted for the most part of weathered bedrock. The weathered bedrock generally consisted of dense, slightly moist, orange-brown, fine sand witb silt and trace gravel. These materials are considered rcgolilh, which is rock weathered to such an extent that it behaves like soil but maintains some features of the parent bedrock, such as bedding planes. This material is suitable for the support of foundations and pavements. Bedrock was em:ountered within exploration pit EP-1. The bedrock was encountered at a depth of approximately 8 feet below the existing site grade and typically consisted of soft, m.oderarely weathered, orange-tan sa11dstone with some smtification (bedding). The bedroc.lc is interpreted to repxesent tbe Renton Formation. We also r«:Viewed the publication Geologic Map of the Rnuon Quadrangle, King ColllllJi, Washington, by D.R. Mullineaux, dilled 1965. This publication shows the site is underlain by bedrock of the Tertiaty-age Renton Formation. Our findings are in generally agreement with those presented in the above-referenced map. Ground water seepage was not cna.mntered in any of the explorations we completed at the time of our field srudy in August 2006. Seepage may occur at random depths and localiom in unsupervised or non-uniform fills_ Fluctuations in tbe level of the ground water may also occur due to variations in the amount of precipitation and changes in site development- 3 PAGE 04 01/12/2007 10:47 3606536852 LPNW INFILTRATION EVALUATION Based on visual observation and our past experience, we evaluated the soils observed within our subsurface exploraiions for !heir potential to infiltrate storm water. Due to their relative high density, line-grained narure, and lb.e occurrence of bedrock at relatively shallow dep!hs, in our opinion, the on-site infiltration of project-geoerat.ed storm water at this sile is not feasible. GEOTECHNICAL EVALUATION Our exploration indicates that, fi'om a geotecbnical standpoint, the parcel is suitable for the proposed development. The bearing stratum is relatively shallow and spread footing foundations may be utilized. Foundations bearing on the weathered bedrock or bedroclc are capable of providing suitable buildin& support. In order to allow foundations to be placed upon recompacted fill soils, AES[ would have to evaluate foundati011 subgrade soil cond.itiona at the time the foundalio1111 are excavated. Existing foundations on the site that are under building areas or not part of future plans should be removed and disposed of off-site. Any buried utilities should be removed or relocated if they are under building areas. The resulting depressions should be backfilled with structural fill. Site preparation of planned buildiog and road/parking areas should include removal of all trees, brush, debris, and any other deleierious mat.erial. Additionally, the upper, organic topsoil should be removed and the remaining roots grubbed. Areas where loose, surficial soils exist due to grubbing operations should be removed down to firm and unyielding soil then brought back to desired grade with structural fiU. Spread footings may be used for building support when founded either directly on the dense, weathered bedroclc or bedrock, or on structural fill placed over these malerials. For footings founded directly upon the dense native soils/bedrock, or on structural fiU we reconunend that an allowable bearing pressure of 2,500 poullds per square foot (psf) be used for design purposes, includiog both dead and live loads. An increase of one-third may be used for short- term wind or seismic loading. Ju S1lllllllaIY, our geotechuical evaluation or the site indicates that the proposed project is feasible from a gemecbnical standpoint, but on-site infiltration of project-generated storm water is not recommended. This evaluation is preliminary in nature in that plans filr the projed have not been finalized. We recommeod that ASEi be allowed to ,:eview the project plans once they have been completed to docwnent that our geotecbnical rewmnzndations have been inco(porated or to provide additional recommendations, as appropriate. 4 PAGE 05 01/12/2007 10:47 3606536852 LPNW We have enjoyed working with you on this project. Should you have any questiom regarding this letter or other geotechnical aspectS of the site, please call us at your earliest convenience. Sincerely. ASSOCIATED EARTH SCIENCES, INC. Kirkland, Wasllingtoa Jon N. Sondergaard, P.O., P.E.G. Principal Engineering Geologist Attachments: Figure I: Vicinity Map Figure 2: Site and Exploration Plan Exploration Logs cc: Land Plannillg Northwest 100 z..i Avenue South, #170 Edmonds, Washington 98020 AUD: Mr. Larry Deisher -Dmll""-' Pl.+m;ucmGIM\G\WP 5 Matthew A. Miller, P.E. Associate Engineer PAGE 06 01/12/2007 10:47 3606536852 LPNW PAGE 07 .; ~ ! ' ,; • V Ill ! V .. .,, Ill .. w • ~ • z<: .. .. .. [I C • z .. • • • • Im • ,c ......... J,llllll \'IIIMW _,_ •i:• 01/12/2007 10:47 I • 3606536852 LPNW SITE AND EXPLORATION PLAN HOUVENER RENTON RENTON, WASHINGTON PAGE N A FIGURE 2 DATE 1/07 PROJ. NO KE05874A 08 01/12/2007 10:47 3606536852 LPNW PAGE 09 ~ LOG OF EXPLORATION PIT NO. EP-1 g This loll Is pall of 111" •=-= i!J A•ocl-E-Solenceo, Inc. (Al/:.Q rw lho no~~ and ollould IHI -" ,_ =::' 11111 ~ lnlelpArlatlon. lJ:le summ,~ only to~ lo on llllo tntnch ,t the i tlrM of n. S.blurfaoo a may cllan119 at l is loal""1 tho -time. The dala presenlad an, Q a simp-of adual candlllono enoounleNd. DESCRIPTION FIii 1 - Dernie, dry, light orange tennfsh brown, fine SAND end SILT, tmoe gravel, trace cobble~; f.w roots. 2 - 3 - 4 - 5 Weatller9d Bedrock (Ragollth) 6 - Dense, slightly moist, omnge.bmwn, fine SAND with slit, trace gravel; highly oxidiZed, moWed texture. 7 - 8 Bedrock 9 - -en, modelllll,ly weathered, orangish tan. SANDSTONE, some stratification of more oxidized aler1al and omanic-rich l=er.1 sllohtlv mot!led texture with oxidaUon. trace ara""'s. 10 - 11 - 12 - 13 - 14 - 15 - 18 - 17 - 18 - 19 - BottDm of up-pit •• deplll 8.5 leel No-·· No ....tng. Houvener Renton Renton, WA r Loggod by: ALO APIJl')vod by: Aseodated Earth Sciences. Inc. Project No. KE06874A 8124106 01/12/2007 10:47 3606536852 LPNW PAGE 10 ft ., f i ; i ~ LOG OF EXPLORATION PIT NO. EP-2 g i Thll log ii """ ol lhe '"""" -= Alo. I .... Ellllh s_c:1 ...... Inc. (AESI) fur U,9 ~rafo<;( and should be reod 11!9effier wfl!, llud Jll!>I!" foi oo III lnlll'll(lllalto. Thl8 oummuy -Mi), to lho of !his lnlni:11 at 111• tme of =:':qr,· Sublurfam ns may i::hlnge 11 thffl location with 'the passage gf Ume, Tl'la date P'N8nted 111n1 u•,,p1 OfOduolcondllooum:01111-. DESCRIPTION FIii Dense, dry, light orange tannlsh brown, fine SAND and SILT, trace gravels; few root,;. 1 - 2 - 3 +------------,,w.,,..,=-==Bed=ccm:-c:.:k-;("'Reg,:-c--o-.,li"th"'I----------- Vary den1e, slfghdy moist, orange-brown, fine SAND and SILT to SILT and fin" SAND, little cisy, highly OJddW!d, mottled texture. 4 - 5 6 -Bottom of ""111.nllon pH at dtplh s feet No saopage. Na coving. 7 - 8 - 9 - 10 • 11 - 12 - 13 • 14 - 15 - 16 - 17 - 18 - 19 - ~t,y; ALO App-by: Houvanar Renton Renton, WA Assuciated E.irth Sciences, Inc. Project No. KE0587 4A 8124106 PAGE 11 01/12/2007 10:47 3606536852 LPNW 1 - LOG OF EXPLORATION PIT NO. EP-3 This leg lo part of lho ra,::J.fl"""'"" l!Y l\11oclalad E8'1ti Sdenooo, Inc. (I\ESI) far the "'"""' oroloct and lllauld ll<II -d 11!9'1ffior wilh -11 far-~ion. Thia ••mmory a1>1>IIN only to the lcc:allon al 1~19 trench II the time of ucavallon. Subaurf&Q!I wndiflonl may c;ttange at this Jocallon with-the pu1ll9e Of timD. The d.ilt. pm19nted a,v a 1lmplficati:;:1 Gf acu.,af cnndlions encounterid, DESCRIPTION FIii Oense. dry, slighHy orange tannlsh brown, fine to medium SAND and SILT, trace gravel; few roots, sllghUy oxidized. 2 -+-------------..W~eatllared-,.,-~Bed~~roc~k~(=Reg-o"'llth,,,..,.)----------- Very dense, sfightlY moist, orange-brown, nne SAND and SILT to SIL Tand fine SAND, ll!Ue clay, 3 - 4 - 5 - 6 - 7 - 8 - 9 - 10 - 11 - 12 - 13 - 14 - 15 - 16 - 17 - 16 - 19 - lrace gravels; slight elralification with oxide~on, mottled te)((ura. Bollom of uplo,otion pll III doplh 3.5 feet Nosaepage. NoC1Mng. ij--==----------------------- " Houvener Renton J Renton, WA j Ii Lonod 1!7; AI.D --by; Associated Earth Sciences, Inc. Project No. KE05874A 8/24/08 Associated Earth Sciences, Inc. January 27, 2006 Project No. KE05874A Mr. Paul Houvener c/o Land Planning Northwest 100 2"" A venue , Edmonds, Washington 98020 111 ~ [I;] ~ lm1 Cefefui~ 2.51fears of Seroit:e Attention: Mr. Larry Deisher, P.E. Subject: Coal Mine Hazard Assessment 1719 Morris Avenue Renton, Washington Dear Mr. Deisher: Associated Earth Sciences, Inc. (AESD is pleased to provide this letter-report presenting the results of our coal mine hazard assessment for the above-referenced site. Authorization to proceed with this study was granted by Mr. Larry Deisher. Our study was based on our visit to the site and accomplished in general accordance with our scope of work letter dated November 21, 2005. This letter-report has been prepared for the exclusive use of the Mr. Paul Houvener, Land Planning Northwest, and their agents for specific application to this project. Within the limitations of scope, schedule, and budget, our services have been performed in accordance with generally accepted geotechnical engineering and engineering geology practices in effect in this area at the time our letter-report was prepared. No other warranty, express or implied, is made. It must be understood that no recommendations or engineering design can yield a guarantee of stable ground or Jack of future settlement or subsidence. Our observations, findings, and opinions are a means to identify and reduce the inherent risks to the owner. INTRODUCTION The proposed project involves subdividing the ex1stmg approximately 0.6-acre parcel for residential redevelopment. The property is located south of the city of Renton on a hill just south of Interstate 405 and east of State Highway 167 (Figure 1). The property is currently occupied by two houses, one built in 1901 and one built in 1912, and a few associated Klddarul Oflia, • 911 Blih.Avenue, Suite 100 • Kiddand, WA 98033 •PI (425) 827-7701 •FI (425) 827-5424 &...rt Office • 2911 1/2 HewittAvorue, Suite 2 • Everett, WA 98201 • P I (425) 259-0522 • F I (425) 252-3408 wwwaesgco.com I outbuildings. The subject lot is relatively flat and generally cleared of trees. The property is bordered by other single-family residences to the north, south, and west, and by Morris A venue South to the east. The areas to the south and east of the city of Renton are known to have been mined for coal in the past. Coal was first discovered in the Renton area in about 1853, with mining occurring at various scales thereafter into the early 1900s. The main coal mine in Renton was the Renton Mine located east of the subject property in Section 20. However, other smaller mines were located south of the city in Section 19, in the vicinity of the subject property. The coal seams are found within the Tertiary age Renton Formation sandstone. DOCUMENT REVIEW AESI reviewed the following documents during preparation of this letter-report: 1. Evans, G.W., 1912, The Coal Fields of King County, published by the Washington Geological Survey, Bulletin 3. 2. Schasse, H.W., et al., 1983, Directory and Users Guide to the Washington State Coal Mine Map Collection, published by the Washington State Department of Natural Resources, Division of Geology and Earth Resources. 3. Livingston, V.E., 1971, Geology and Mineral Resources of King County, Washington, published by the Washington State Department of Natural Resources, Division of Mines and Geology. 4. Mine Map K32(A), Renton Mine, Renton Coal Company, 1920, shows old Talbot Mine, Sunbeam Mine and Patton Mine, Washington State Coal Mine Map Collection, Washington State Department of Natural Resources, Division of Geology and Earth Resources. 5. Bagley, C., 1929, History of Coal Mining in Washington, in the Breathless Moon, The Burgess Legacy Genealogy Project. 6. Mullineaux, D.R., 1965, Geologic Map of the Renton Quadrangle, King County, Washington, United States Geological Survey GQ 405. Review of the above-referenced documents indicates that the subject property is underlain by the Old Patton Mine (Figure 2). The Patton Mine was opened in 1872 when a slope was excavated down one of the Renton coal beds. There were three main coal seams in the Renton area, the No. l, No. 2, and No. 3. The No. 1 was approximately 17 feet thick, the No. 2 about 13 feet thick, and the No. 3 about 11 feet thick. In the vicinity of the subject site, the coal seams were gently inclined to the south-southeast at a dip of approximately 7 to 10 2 degrees. Apparently only two levels were worked in this mine. Little information is available regarding the Patton Mine and its workings. COAL MINE HAZARD ASSESSMENT Title 4, Chapter 3, Section 4-3-050(J)(l)(e) of the Renton Municipal Code (RMC) defmes coal mine hazards within the city of Renton. The coal mine hazards are subdivided into three categories defined as follows: Low Coal Mine Hazards (CL): Areas with no know mine workings and no predicted subsidence. Medium Coal Mine Hazards (CM): Areas where mine workings are deeper than 200 feet for steeply dipping seams or deeper than 15 times the thickness of the seam or workings for gently dipping seams. These areas may be affected by subsidence. High Coal Mine Hazards (CH): Areas with abandoned and improperly sealed mine openings and areas underlain by mine workings shallower than 200 feet in depth for steeply dipping seams or shallower than 15 times the thickness of the seam or workings for gently dipping seams. These areas may be affected by collapse or other subsidence. The records for the Patton Mine are scarce and details of the workings are unknown. The coal mine map (K32) referenced above shows the outline of the mine workings, but does not provide any elevations for the slopes, gangways, or seams. The location of the mine, as shown on Figure 2, may also not be quite accurate due to the difference between survey datum used when the map was made and present day. Based on the site topography, it may be that the entrance to the mine was north of where it is plotted, on the slope where outcropping seams would have been more evident. However, with the low dip angle (7 to 10 degrees) of the seams in this area, the subject property would still be underlain by the workings even if the entry was actually north of where it is plotted. The maps and records do show that the main entry to the mine was a slope, which typically means the workings entered directly onto the seam and drove down the dip of the seam before mining gangways along the strike of the seam. The records also do not indicate which seam of the Renton Coal Beds was being mined at the Patton Mine. Assuming that the shallowest seam (No. I) was worked, then applying the 15 times rule to the thickness of the seam (17 feet) would result in a depth of 255 feet. Since the topographic relief between the subject site and the base of the slope to the north is only about 100 feet, it seems likely that the mine workings are within a depth of 255 feet from the surface since the entry was a slope located on the seam that outcropped on the hillside to the north. Based on this criterion, the vicinity of the subject property would be classified as a High Coal Mine Hazard Area according to the RMC. 3 During our field reconnaissance of the subject property, we did not identify any surface features indicative of mine openings, settlement, or subsidence. We also did not observe obvious indications of these types of features on surrounding streets or property. Although, based on the low dip angle of the seams, it is likely that the workings occur at relatively shallow depth beneath the site, the age of the workings (late 1800s) suggests that if the mine was prone to subsidence manifested by surface settlement, such settlement would have occurred by the present time. COAL MINE HAZARD MITIGATION In our opinion, the proposed development will not increase the threat of settlement or subsidence on the adjacent properties beyond pre-development conditions, will not adversely impact other critical areas, and the proposed development can be safely accommodated on the site. To mitigate for potential future mine-related settlement or subsidence, we recommend that all building foundations consist of continuous strip footings with no isolated column or pad footings. It must be understood that, unless the abandoned mine workings are properly closed and filled, there will always be some risk of mine-related settlement or subsidence at the site. Sincerely, ASSOCIATED EARTH SCIENCES, INC. Kirkland, Washington Jon N. Sondergaard, P.G., P.E.G. Principal Engineering Geologist Attachments: Figure 1: Vicinity Map Matthew A. Miller, P.E. Associate Engineer Figure 2: Approximate Location of the Patton Mine JNSfld KED5874Al Projt:cts\200S0874\K.E\WP 4 t J ; =--.-=-==-== J 1 ! Vt ('=....-"'"'I ----~-- "' l 1· "'--· ~ __ .'.?~----? .-------·· -------:-------------- ·-< i1i I 1:i.Trl • ) 1----.... -------~ --p I -----· ;_§: I SI ~ I S\~ .1#..J...--· :;; I ,~--16~ ~I ~I ~,~---. t'.11,~ ., . ,ti1 '···.,,, f;,i ~- 1.it. ~I < ' / (~------"· . ·\ . ;,_"'' ' ... · .. ··-~.~-.. ~ ·· . . . --~~t~i; N ;5 :;::sl w'--' .. ! ~ ,~j ST w lJ.J ...J ~ CL '.3 __ J,_ ~ f~ z .i·!T!.. Tf..Y/ ~-J'1:.."'l.l£.'/ t}P/ Q Sft~TT!...£ -.f~EN!f.~'l 0::. -·------------- ~ , , SlJ/ 19TH · ST >- LU FS .. ....J .....J <( > J; A -~ ~ ~ m ~ NO SCALE C • ii "' I Associated Eaf"th Sciences, Inc. 0 ~ ~ rm l!i ~ "' • Si 0 ?'!L.Uk;f (£..'lrE~ S REIITOH VILLAGE -·-·-··-·--- PL 2 ~\ , ., _y' 1\:,.. . . .. v·, .. --~ _,. . . . :,: v, "' "' .-----·----:/, ~ !:! '-'' ~ '":- / ,::, ,;.;: ~-;;$ i;;~_.:_.itli.{/T><itr __ s ~ :se ;f•l: __ J_~J5Tfl i1r\i!j'f,:l· '/l ·, > -r .. 1·h,.,. ~ <: "' ~(-· C) , U) I ... \~ ~\ . , I : S 16_:!1_1_ ST_ · ·· · ·"' I I · ' 1·ri• ,:._) s 'f-1 I ..I" I ::, ~ • .II '1 \ ,-< I I, <. _ , • , '"1T~I C'T I \y ::51 !..:!-_(_I__( __ .,__, __ , 'r-~· ·-' ,' '1 -/-I I/"/ \ -\ ~\?J8TI!_/ ,•\I SITE ' c.., ST ·· ~,,,. ,p ·, I ~ ! ~/ ~~>:·l~ ·..,.,..~...,,..,.,. ··.-· .. :.. __ , __ ... -.\-l __ ·:1.____ / ·-~ 19TH (/) \ ' ,J~ \ \ ·O' ~l\ *·\ '_.,\ \ ,;~.·~ 21STfT VICINITY MAP HOUVENER RENTON RENTON, WASHINGTON ! i I \ \, \. 6'T1Qjij §J ·· , 1· -;,, I ..;.... \ tr2 !...,----··, ~ :;,, -rl I ' \ :I \ \ \ I.J.J .\ ,n I ,,, i::'.) .. ~\~q. . '•. s ··._.lo'>, ·. '/;I ')::a \< I, \ .... ..: \"' ~'7t~l I ,:,:.;, <i<\ 1-I i.,lil• ===I·~ s~ FIGURE 1 DATE 1/06 PROJ. NO. KE05874A I I' i N w a: ::, !2 u. • '~---- .. . " ! w < C w z :a: .; • ~ i;; "' fil "' ci z -; 0 0: Q. j lli • .. f~ • .. .., i [ii • 0 ~m Section VII. Basin and Community Planning Areas !I/A I Section VIII. Other Permits Section IX. Erosion / Sedimentation Control Design IX. Erosion I Sedimentation Control Design There are no onsite roads or frontage improvements associated with this project. The three new lots may be improved by a single developer or multiple developers. The total onsite grading quantities are anticipated to be less than 500 cubic yards. Consequently, the need for erosion control measures are minimal and will most likely be applied individually to each lot. Standard erosion I sedimentation control BMP's will be employed in conformance with Core Requirement # 5 as follows : ( 1) Clearing Limits: It is anticipated that the new lots may be entirely cleared as there are no critical areas onsite. Some trees and other existing vegetation may be selectively retained depending on the individual plot plans. The minimal grading necessary to improve the lots will not occur closer than two feet to the property lines in accordance with UBC. (2) Cover Measures: Temporary and permanent cover measures are identified on the plans. The timing for implementation will be subject to City of Renton standards or in conformance the minimum requirements listed on the plans. (3) Perimeter Protection: Perimeter protection in the form of silt fencing will be applied to the down-slope limits of the disturbed area of the lots. These will be placed along the property lines or immediately up-slope of vegetated areas to be retained. ( 4) Traffic Area Stabilization: There may be multiple entry points for construction activities coinciding with the permanent lot entries. Full size gravel construction entrances may not be possible or warranted. It is anticipated that the extent of stabilization required will be subject to the direction of the City inspector and also dependant on the time of year that construction occurs. Minimum stabilization measures ( as required) are listed on the plans. (5) Sediment Retention: The limited area(s) of disturbance and grading does not appear to warrant the need for sediment traps, especially of construction occurs during the dry season. CB inserts are recommended and specified on the plans. (6) Surface Water Controls: All surface water control will be provided by the perimeter protection noted above. (7) Dust Control: It is not anticipated that dust control will be a factor on this project. Minimum dust control measures (as needed) are listed on the plans. (8) Wet Season Construction: Wet season construction limitations and requirements shall be in accordance with City of Renton requirements. (9) Construction Within Sensitive Areas and Buffers: Not applicable to this project. (10&1 l) Maintenance & Final Stabilization: Notes pertaining to maintenance of TESC measures and final stabilization arc provided on the plans. Section X. Bond Quantities Worksheet ® ICiq Couaty l)epartPHld of Dffelopamt amt Eatiro1111H111t&I Slrritfa 3600 136th P!aco SouthCUI Belle.we, Wubiagton 98006-1<400 Project Name; j/c,ov' e.,-1 ;;!,p, 5;/o,e.,'(' ?£-.l'lr SIERRA Project No.: /V /,,, Date: ------ Location: C:,:f'f e:.z;:::::· ,(:Bi,ua/ --Sierra Activity No. ~~~,_!J'J~~---- -· = -l .~ '/ 1,, k ,, I 11 F:OR ~TIRE Pflci:J~C'f'':} .t~\.::"' '·:,'..::.; :. ;Q441ntlty,.,:>: /'.~rl~:? EROSION/SEDIMENT CONTROL -- Fenoe, •HI I 1.30 LV l /00 l /'3Q HydroHllding ·"° SY Jut• Mti•h 1.00 SY Mulch, by hand, straw, 2· deep ••• sv I 5i:¥? I l1C' Mulch, by machine, straw, 1 • deep ·"° sv Rook Con,tt Entranc•, 60' JC 15' • 1' 1,030.00 .... I / T 10.10 RoDlc. Constr Entranc•. 100' x 15' IC 1' 1,800.00 E,oh Seeding. 1:iy hand .3' sv ESC SUBTOTAL CIHr/R1move Bru•h~-~ hand .24 sv SUBTOTAL FOfl.PN.U" ci~<:i{" ,,,~'-J":t,·· ,l~_ 1 ·._Jf~~{P£_ir_Jt_,f_,_,_. f'c,a,,.cuel:'T',;;-.. '""i,,~J!!l:t2\tw.~;!l},,·L I'' ,h:·u"' ·"' 9l~E'RAL ITEMS jCo~:Ll_ c1 ... rt-1GNbbrna/Remov,1 1, ... Exo.vatlon -bulk Excavation -tranch S.ckfiN & Co-"aotion • embankment Backfill & Comnactfon • lrt1nch Fifi 6 Ci:,--aot -common barrow Fill & c--aot • "raYtll bate Filf 6 Co-·-ect • •crunl!Nl-1011 Gradin11 fine with nrllcf11r Gradi--fine b"' hand F11noi--cedar. 8' hfah Fencl--oh.In llnk &' hiah F11nclnn chain link net. :20' Fencfnn tamnOt"arv lNGPE'I Sod Monumant•. 3' to- SurveU n" lot loc11tlon/llnott Survttvinn line & nrade Trait 4" cfl.Jshed cinder Trail 4" too counie Gablon 3' 1hlck no Hrrhwotk _wan, r•talni!!a 1 rook.a~ w/11m,hwork -- I 150.00 .. ,. 1.10 CY MO CY <?0 oCJ 3.110 CY 5.70 CY '70 ,,41 I ' ' 11.10 CY 15.60 CY 15.40 CY .70 SY 1.30 SY 25.00 LF 9.20 LF 880.00 .... 1.10 LF 4.82 SY 84.00 Each 830.00 .... 510,00 o- I.SO SY e.oo SY 97.00 SY 21,@ __ SF_ SUBTOTAL Potll'MI c...u*"•· 12.IM4 Paga 2 NP/'t": ;, ( Sl•rra ProJ.ot No. Jw Irr __ _ ,9, do z4U "'-0 :>.>lo 7,0 '2.JO I 70 l-:3~ ' ' ' ;~fl /!!'l<'c..,Alltlif"1o,J a l!!JA~U-- /t,JC,,, WA~, SS "1/40 <S"r~ ROAD IM_PAOVEMENTS AC Grinding_,_ 4' machine 7.00 AC Aemov-111/0ls-posal/R~r 80.00 Ehirric!lde_,_ type Ill 30.00 B11rricltde_,_ type l 20.00 _Curb, 11xtrud11d -11sph11h 1.80 Cur~, ex!ru~&d conc,ete 1.BO Curb & Gutter, rolled ~.30 Curl:>_ i _(i1,1n~rL ver1ic111 IS.SO C11moli1lon/Cl1po~l~~l.lm~ru:~ 10.30 _Q~moli1ionlQ_i11po111l, 11id11w11lk 22.$0 Sawcut,.11spfudt, 3• depth 1.30 S1111wcut, concrete, per 1" depth 1.10 Sealant _,_7:9 __ Shoulder, AC, 111111 AC flo,ad ~houkter, gravel 6.4() Sldewelk1 ,t" thick. vertical curb 20.80 ~!"awalk, 5• thick, rolled curb ~3.80 ~~riping, 4" reflectorized line .20 J_!!i_pl_n11,.P~'-patklng 11tt1H 2.90 Thicken~ ~dg~ -t.70 ROAD SURFACING 14" rock • 2.5 bae• & 1.5" top courul ~~ (h,eitay,_1,S• AC 5.4() AC Owitay_._ 2" AC 6.50 SY SY LF LF LF LF LF LF LF SY LF LF LF SY SY SY SY LF Eeoh LF ID': sy :\oos~h\; .. , ·-::\i. FUTUR(~'.i<.:::~ ~l~H!,OfiWA'(ii (RO~D@/;l!'if#XS,0 ;;,yJ;>WH'lt:r.::yg::: IM~OVl!Mf~::-:n ·· .44 "'Z 4-o U? h I '< '9 SUBTOTAL fOR PAO[ Sle•r• Project No. ------- . ·•.;;.:.• //1#7 ;5r,,, .... i.. /1-t::' £_4- 4c> \U-~ ii" s-ioe S.:WetUS 6 WA16.(1.. Sl!=/2-V/CJ:::. Sierr• Proi-ct No. Jf, <'t-t )<'· PrfOI Oi.lentlty AOAO SURFACING (Can't.} AC Roed. 2" 4" rock. Rret 2500 SY 13.70 SY AC Roed r 4" rook a-. over 2500 SY 9.10 SY AC Road 3" -4• rock Arlt 2500 SY 16.50 SY AC Road. 3•_ 4" rock-Qtv, O'll'er 2$00 SY 11.00 SY AC Roed 5• Flrat 2500 SY 16,30 SY I AC Aoed s· Qh.o, over 2500 SY 10.80 SY ~I / //l AC Roed 6" Fin11t 2500 SY 19.10 SY ll'Y 1r· AC Roed l!I" ON. over 2600 SY 12.70 • SY Arhelt TrHted BHe IA. TB) I Assume 2.05 ton/avd) 30,00 Ton Gra11.r Road 4" rock Firat 2500 SY 7 . .20 SY Gravel Road. 4" rock Qtv, ov.r 2500 SY 4.70 SY PCC Road 5" no bH• 14.30 SY PC~-B.~~. 5", no ~Ill~~---11!1,SO SY I Q_fW_~~O_I ICPP • ~grr~gated P1111tic Pipe, N· 12 or equlvalentl Acee11 Ro~.L_f'UO 9.30 SY ~J11rd• -fhu1d 290.00 tM.h Bollards -remov!!)Je ~75,00 •~• ICBs include frame and_fu!L_ / EJ .,;·-~@ Q44',,,l"j --2"0.rl' tfAe.;./ d 1,.,,::,0 !;I Typ~ 8~,()Q -z. ~Jype/j._ 1,_000.oQ_ -ca 1'.'YP• 11, 48" ~--1,300.00 4 .. d_ Jor ~anal d'apth OWlf 4' ... ,20.00 ~ ,. dMdh 8U8TOT AL l'Oll l'AOI CIM'4MN • 12.IIJM Page4 ( ( -------------------e e $i•rr• flfoj9ct No.------ DRAINAG!: (Con't,I --~~·---·--------·--1~~ --1 450.00 4'd••· +-370.00 ,j,.l' donlh CB Tvo11 !I, eo· diemeter 1.600.00 4' dee, for .&ddilionai d"pth over 4' +410,00 + 1' daoth ca Yvce II ?r diome,.,, 2,200.00 4' deoth for ado\tionel dll!lpth over 4' +520.00 +i• deoth Throu11h-c-urb Inlet Fu1rnework lAddl .225,00 E•cn ctHnOUt PVC 4• BB.00 feeh Cleanout P\/C. s· 11$.00 .... C\eani::iut, PVC a-142,00 bch_ Culvert PVC 4" 4.50 LF Culven CPP'. e:• 9.30 LI' C1Jlvert PVC 8'" &.40 LF I I I I I ,&a jq,;4- I I I I I I Culvert, CMP 13" 9.50 lF CWvert, concr•te a• 12.110 LF C1:1lwrt CPP. 8'" 10.00 lF CWvett PVC S" 8.00 LF Culv•rt CMP, 12" 14,60 lF CulV11rt. <10ncrota 1 2" 17.90 LF Culvert. CPP l 2" 11,50 LI' Cu1<1t1rt CMP. 1S" 18.70 LF Cui'Vart ooncf6te 15" 22..50 LF Cu\vtn. CPP l 5" ,a.so lF culvert. CMP, ur 21.90 LF ---- S\JllTO"tA.l fOl\l>-._GE l,,.fi: I I ~ GE Con't.) C art1 concret•1 1 s• 27.60 LF Culvart1 CPP1 1 a• 21.00 LF Culvert1 CMP 1 24• 30.30 LF C:ulv•rt1 concrata1 24• 39.10 LF Culvert1 CPP1 24• 29.00 LF Culvert1 CMP1 30• 38.IO LF Culvert1 concrete1 30• 84.70 LF Culvert1 CMP1 36• 92..80 LF C:ulwrt, concret•, 3g• 83,20 LF Culv11r_t, __ C::_J'~ 36• 39.00 LF ~i,,lvart, r;::o"_i;t_ret•, _4l:_" 101,80 LF Culvert, C:MP, 4S-80.80 LF Culvert, concrete, 48" 113.00 LF Cul1,ert, CMP, 6()" 112..00 LF Culvert, concrete, ea• 154,00 LF Ditching, t;,ara, tpadm• 5.40 CY Flow Oiepereal Trench 1,100 bu•+ 1s·.oo LF .fJe~h Orai_n 12.30 LF Mid-tenk AcceH Rieu, 36• 700.00 .. oh Pof'!d_ Ovllrflow _SpllJWav 4.70 SY Rntriotor/Oil Sae-retor1 1.2• 785.00 .... ~111tlctorlOII Separator, 1 s· 115.00 .... RHttlctor/Oil S-s,eretor,_1_•• 1,c,35.00 - SUBTOTAi. ~#IH·1:IIWM -- MUftE_::~c·.:,c::_,_, ·/. \;;~ME.~~J);t:'. ti . ;--A,~ ltH Ouanth'i' Pflc. I I I Page 6 . I l Y/ I I I I , • --- .:t1•rra Pro1acl ...... ------ = )t / I. I --- DRA.IN_AGl;1Con't.) Rlpra~. pldced 28.00 Tank End Raducar 400.00 Trash Rtick,_ 12~ 160.00 Tra$h Rack, 15" 185.00 Truh Rael<.,_ 18" ;!:JO.QO Trash Ra_c;k,__t1" 240.00 ~~RKING LOT SURFA_Clr,,_g r...A,~:L !" tO_F!_course rock & 4" aeleot borro~ 8.10 1 _ _._!j;~ IOCI courto rock & _2_._5_'."_~H CO!JIH 4,70 4~ !!lec_t ~Q_rrow 1.75 WRITE-IN ITEM& -. I Li. ,, J./ Jttf?{J--,, ""' ,, CY Each Each Each E_ach Each SY SY SY l'c,!!, (~ANAf£\¥%\: }:<i/i{~ ''Jl.1.PROVQAENTl·Ig\::,-, ,,-:,:g/{G: ,, 3 i!,D0 I I II W ,dg.£ )#M//c..Ji ~. ex:> /,::: /0 ,.,,,_.,, 6 '1 S1!7C' -1, .,=; I/ C, &>, 6.,:/o I.P I J,::, e;'fi SUBTOTAL ISUM ALL PAGES): ------------ 30'% CONTINGENCY & MOBILIZATION: ------------- TOTAL: ' <::> -;t<Z..t: :j' ,;,I,<; Slerre ProJoct No.------ (Al (Bl (Cl Quantities above w pleted by: Signature~ Date: -------- PE Registration Numbe,: Tetephone Number: ------ Firm Name:----------------------- Address: ----------------------- This section to be completed by King County BONO COM PUT A TJONS: Stabilization/Erosion Sediment Control [ESCJ Existing Right-of-Way Improvements Futwe Public Road Improvements · Private Improvements A/D Facilities and Conveyance Systems PERFORMANCE BONO AMOUNTS 101 ___________ _ IE! ___________ _ IFI ___________ _ TOTAL Im, _________ _ PEflFORMANCE BOND·AMOUNT RIGHT-OF,WAV & SITE RESTORATION BONO I 1D+E! ___________ _ (Fl"t '7,500 of bond shaR be calh.J PERFORMANCE BONO TOTAL AFTER BONO REDUCTIONS ,, ____________ _ . IT·A,B OR Ci j 12, ___________ _ 13, ___________ _ Original bond computations Si•n• Proi•ct No .• MAINTENANCE BONO AMOUNT DEFECT SONP AMOUNT IE+FI x 0.26 • ,c 0, 16 • ------------ Signature of Person Preparing Bond Reduction ~OTE: The word •bond~ is used to represent any financial guarantee acceptable to King County. prepared by: -----------Date:------ ---- I I Page 8 I ''---------~~ Dote 12: ---------,.= -OaUI 13·---------= °"" NOTE: T°""--_,.,. oft•---.. --301'eldlowlglnll __ ..__., .... ma&na.nance Md defNI .................... •hid•• .. -· ( Section XI. Maintenance and Operations Manual K I N G C O U NT Y, WA S H I N G T O N, S U R F A C E WA TE R D ES I G N MA N U A L NO. 5 -CATCH BASINS Malntenanee Component General Defect Trash & Debris (Includes Sediment) Structural Damage to Frame and/or Top Slab Cracks in Basin Walla/Bottom Settlement/ Misalignment Fire Hazard Vegetation Pollution CondlUona When Maintenance lo Needed Trash or debris of more than 1/2 cubic foot which is located immediately In front of the catch basin opening or ls blocking capacity of basin by more than 10%. Trash or debris (In the basin) that exceeds 1 /3 the depth from the bottom of basin to invert of the lowest pipe into or out of the basin. Trash or debris in any inlet or outlet pipe blocking more than 1 /3 of its height. Dead animals or vegetation that could generate odors that would cause complaints or dangerous gases (e.g., methane). Deposits of garbage exceeding 1 cubic foot in volume. Corner of frame extends more than 3/4 inch past curb face into the street (if applicable). Top slab has holes larger than 2 square inches or cracks wider than 1 /4 inch ~ntent Is to make sure all material Is running into the basin). Frame not sitting flush on top sfab, i.e., separation of more than 3/4 inch of the frame from the top slab. Cracks wider than 1 /2 inch and longer than 3 feet, any evidence of soil particles entering catch basin through cracks, or maintenance person judges that structure is unsound. Cracks wider than 1 /2 inch and longer than 1 foot at the joint of any inlet/outlet pipe or any evidence of soil particles entering catch basin through cracks. Basin has settled more than 1 inch or has rotated more than 2 inches out of alignment. Presence of chemicals such as natural gas, oil, and gasoline. Vegetation growing across and blocking more than 10% of the basin opening. Vegetation growing in inlet/outlet pipe joints that is more than six inches tall and less than six inches apart. Nonflammable chemicals of more than 1/2 cubic foot per three feet of basin length. A-5 Reaulta E,pected When Maintenance la Performed No trash or debris located immediately in front of catch basin opening. No trash or debris in the catch basin. Inlet and outlet pipes free of trash or debris. No dead animals or vegetation present within the catch basin. No condition present which would attract or support the breeding of insects or rodents. Frame ls even with curb. Top slab is free of holes and cracks. Frame is sitting flush on top slab. Basin replaced or repaired to design standards. No cracks more than 1/4 Inch wide at the joint of inlet/outlet pipe. Basin replaced or repaired to design standards. No flammable chemicals present. No vegetation blocking opening to basin. No vegetation or root growth present. No pollution present other than surface film. 1/90 KI N G C O U N T Y, WA S H I N G T O N, S U R FA C E WAT E R D E S I G N MA N U A L >. 5. CATCH BASINS (Continued) Maintenance Condition• When Maintenance Component De!Kt lo-ed Catch Basin Cover Cover Not in Place Cover la missing or only partially In place. My open catch basin requires maintenance. Locking Mechanism cannot be opened by on• Mechanism Not maintenance parson with proper tools. Working Bolls Into frame have less than 1 /2 Inch of thread. Cover Difficult to One maintenance person cannot remove Remove lid after applying 80 lbs. of lift; intent la keep cover from sealing off access to maintenance. Ladder Ladder Aunga Ladder is unsafe due to missing runga, Unsafe misalignment, rust, cracks, or sharp edges. Metal Grates Grate with opening wider than 7 /8 Inch. (if applicable) Trash and Debris Trash and debris that is blocking more than 20% of grate surface. Damaged or Grate missing or broken member(s) of Missing the grate. A-6 R•ulta Ex_...i When Maintenance la Performed Catch basin cover Is cloud. Mechaniam opens with proper tools. Cover can be removed by one maintenance person. Ladder mMls design standards and allows maintenance person safe access. Grate opening• meet design standards. Grate frff of trash and debris. Grata Is In place and meets design standards. 1/90 K I N G C O U N T Y, WA S H I N GT O N, S U R FA C E WAT E R D ES I G N MA N U A L NO. 10 • CONVEYANCE SYSTEMS (Pipes & Ditches) Maintenance Component Pipes Open Ditches Catch Basins Debris Barriers (e.g., Trash Rack) Defect Sediment & Debris Vegetation Damaged Trash & Debris Sediment Vegetation Erosion Damage to Slopes Rook Uning Out of Place or Missing (If Applicable) Condition• When Maintenance la Needed Accumulated sediment that exceeds 20% of the diameter of the pipe. Vegetation that reduces free movement of water through pipes. Protective coating is damaged; rust is causing more than 50% deterioration to any part of pipe. Arty dent that decreases the cross section area of pipe by more than 20%. Trash and debris exceeds 1 cubic foot per 1,000 square feet of ditch and slopes. Accumulated sediment that exceeds 20% of the design depth. Vegetation that reduces free movement of water through ditches. See "Ponds" Standard No. 1 Maintenance person can see native soil beneath the rock fining. See "Catch Basins" Standard No. 5 See ~Debris Barriers" Standard No. 6 A-11 Rnultl Expected When Maintenance Is Performed Pipe cleaned of all sediment and debris. All vegetation removed so water flows freely through pipes. Pipe repaired or replaced. Pipe repaired or replaced. Trash and debris cleared from dit¢les. Ditch deaned/flushed of alt sediment and debris so that it matches design. Water flows freely through ditches. See "Ponds" Standard No. 1 Replace rocks to design standard. See "Catch Basins" Standard No. 5 See "Debris Barriers" Standard No. 6