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09-0239 Pre Stormwater Site Plan 111609• Prepared For: LS Construction 20900 Cooley Road Bend, OR 97701 Prepared By, Jeremy F. Haug, E.%.T., Project Engineer Approved By: Brett M. Allen, P.E., Principal Project # 09-024 1 hereby state that this Stonn Water Site Plan for Les Schwab Tire Center of 805 Yelm Avenue East has been prepared by me or under my supervision and meets the standard of care and expertise Malls usual and customary in this communityof professional engineers. I understand that City of Tacoma does not and will not assume liability for the sufciency, suitability or performance of drainage facilities prepared by Contour Engineering PLLC This analysis is based on data and records either supplied to, or obtained by, Contour Engineering, PLLC These documents are referenced within the text of the analysis. The analysis has been prepared utilizing procedures and practices within the standard accepted practices of the industry. TABLE OF CONTENTS PAGE 1.0 PROJECT OVERVIEW.................................................................................................................................2 PURPOSEAND SCOPE................................................................................................................................................. 2 PROiEc'r DIiSCRIPTION.............................................................................................................................................. 2 2.0 EXISTING CONDITIONS SUMMARY..................................................................................................... 3 3.0 DOWNSTREAM ANALYSIS....................................................................................................................... 4 4.0 STORMWATER CONTROLS...................................................................................................................... 5 EXISTINGSi m, HYDROLOGY...................................................................................................................................... 5 DTVELOPE D SI'Z'E HYDROLOGY.................................................................................................................................. 5 P1.-'.R1'ORMANCE STANDARDS...................................................................................................................................... 5 Fi.OW CONTROL SYSTEM........................................................................................................................................... 5 WATLRQUALITY SYSTEMS....................................................................................................................................... 6 S'T'ORM DRAINAGE CONVEYANCE SYSTEMS.............................................................................................................. 6 5.0 DISCUSSION OF MINIMUM REQUIREMENTS................................................................................... 6 Appendix A' General Exhibits Appendix '8' Geotechnical Report Appendix 'C' Retention Pond Analysis Appendix 'D' Water Quality Systems Sizing and Specifications Appendix 'E' Conveyance Calculations 1.0 PROJECT OVERVIEW Purpose and Scope This Preliminary Stormwater Site Plan report accompanies the Site Plan Review application and Short Plat application submittals for the proposed Les Schwab Tire Center at 805 Yelm Avenue East as submitted to the City of Yelm. This document provides site information and the preliminary analysis used for the stormwater conveyance and retention pond designs, as well as the water quality facilities for both the Les Schwab site and the access roadway. The 1992 Department of Ecology Stormwater Management Manual for Western Washington (DOEManuan establishes the methodology and design criteria used for this project. Project Description The proposed project will consist of a short plat subdivision of the existing parcel into two lots and a tract. The site is currently within parcel 22730121100 which is approximately 299,457 sq. ft. (6.87 acres) and is zoned Commercial C-1. See Vicinity Map in Appendix `A'. Lot 1 will include the proposed Les Schwab Tire Center which will comprise of a 11,751 sq. ft. building with 48 parking stalls, associated drive aisles, loading areas and landscaping. The existing house and accessory buildings will be demolished and removed. Lot 1 will contain an underground storm drainage system separate from either Lot 2 or the Tract. Lot 2 will encompass the remained of the site (excluding the Retention Pond Tract) and include the existing church buildings, facilities, and parking areas as well the access and utility easement for the proposed roadway. The retention pond tract (Tract A) is located along the southern property line and is 60 -ft in width. This pond is sized for the Les Schwab site, the access roadway, and the existing church facilities as well as the possible future expansion of the church facility and its parking area. Legal Description Parcel 22730121100 THAT PORTION OF THE NORTHWEST QUARTER OF THE NORTHEAST QUARTER OF SECTION 30, TOWNSHIP 17 NORTH, RANGE 2 EAST, W.M., DESCRIBED AS FOLLOWS: BEGINNING AT A POINT ON THE SOUTH LINE OF SAID SUBDIVISION 310 FEET WEST OF THE SOUTHEAST QUARTER CORNER THEREOF; THENCE WEST 350 FEET, MORE OR LESS, TO THE SOUTHWEST CORNER OF THE SOUTHEAST QUARTER OF THE NORTHWEST QUARTER OF THE NORTHEAST QUARTER; THENCE NORTHERLY ALONG THE WEST LINE OF SAID SOUTHEAST QUARTER OF THE NORTHWEST 2 QUARTER OF THE NORTHEAST QUARTER AND ALONG THE EAST LINE OF A TRACT CONVEYED TO JOHN CUBIT BY DEED RECORDED IN VOLUME 100 OF DEEDS, PAGE 201, UNDER RECORDING NO. 98937, 1017.5 FEET, MORE OR LESS TO THE SOUTHERLY LINE OF SECONDARY STATE HIGHWAY NO. 5-H; THENCE SOUTHEASTERLY ALONG THE SOUTHERLY LINE OF SAID HIGHWAY TO A POINT NORTH OF THE POINT OF BEGINNING; THENCE SOUTH 737.12 FEET MORE OR LESS, TO THE TRUE POINT OF BEGINNING. EXCEPTING THEREFROM THAT PORTION CONVEYED TO THE CITY OF YELM BY DEED RECORDED OCTOBER 25, 2001 UNDER AUDITOR'S FILE NO. 3387674 FOR ROAD. IN THURSTON COUNTY, WASHINGTON 2.0 EXISTING CONDITIONS SUMMARY Pre -Developed Site Conditions Currently, the parcel contains many structures scattered over the northern half of the parcel. The church facility is comprised of two main buildings and is located toward the west side of the site. There is a residence toward the northeast portion of the site, and there are several accessory buildings scattered throughout the site. Topography and Ground Cover The topography of the site is relatively flat with an overall slope from north to south of less than 0.5%. The parcel is primarily grassed in the southern half with not trees, structures or impervious surfaces. The northern half contains grasses and scattered trees of mixed varieties, as well as the existing structures, gravel parking area, basketball court and playground area. Adjacent Land Uses The parcel is bordered to the north by Yelm Avenue and to the south by a pond facility for the housing development to the south. A commercial property, Rite Aid, is to the northeast with a residential property to the southeast. To the northwest lies a commercial development, which contains the Country Inn Restaurant, some mini -storage, and a small strip mall. To the southwest, lies several residential properties. Native Soils and Groundwater The native soils have been mapped as Spanaway gravelly sandy loam (110) and Spanaway stony sandy loam (112). See Geotechnical Engineering Report as Appendix 'B'. 3 The site is located outside the Thurston County High Groundwater Hazard Area. No groundwater was observed at any of the test pits. See the Geotechnical Engineering Report as Appendix 'B'. Drainage Patterns It is assumed, based on the native soils and the relative flatness of the site and adjacent properties, that all stormwater infiltrates on-site and that there is no off- site stormwater entering the site. There are no known drainage or erosion problems on the project site. However, per representatives of Our Redeemer Lutheran Church, stormwater does pool on occasion in the existing gravel parking area in front of the church facilities. This drainage issue does not have an impact on the subject site and will be addressed in future permits applications. Critical and Sensitive Areas There are no known wetlands or any other sensitive area within 300 -ft of the project site. Other Existing Site Information There are currently two wells on the existing parcel. One is located along the western property line, midway between the church and the northwestern property corner. This well is to remain for utilization by the church facilities. This well will be capped and decommissioned as part of this project. To our knowledge, and based on the DOE Well Logs, there are not other wells within 200 -ft of the project site. There is an existing septic drainfield for the church located east of the existing facilities and a septic tank located between the two current buildings. This system will be decommissioned and removed, and replaced by a sewer STEP system. The permit application for this sewer STEP system is forthcoming. Both the well capping and decommissioning, and the septic decommissioning will be done per current Thurston County Health Department and Department of Ecology standards. There are no known underground tanks within the subject parcel. 3.0 DOWNSTREAM ANALYSIS Since all stormwater will be collected, conveyed and infiltrated on-site, not downstream analysis is required. W 4.0 STORMWATER CONTROLS } Existing Site Hydrology It is assumed, based on the native soils, all precipitation currently infiltrates on-site; Developed Site Hydrology The post -developed parcel will contain the developed area and some area that will be left in its native condition. See the Basin Map Exhibit in Appendix 'C'. The developed area (Retention Pond Basin) will consist of Lot 1 (Les Schwab), the access roadway, the existing church buildings, facilities and parking area, and a portion of area south of the existing church for a possible building expansion in the future. The post -developed site hydrology will consist of the following areas: Total Parcel Area = 299,457 sq. ft. (6.875 acres) Total Retention Pond Basin = 185,329 sq. ft. (4.255 acres) Total Tract Area = 21,116 sq. ft. (0.485 acre) Total Area to Remain in Native Condition = 93,120 sq. ft. (2.138 acres) The Retention Pond Basin area is used for sizing the retention pond and takes into consideration the future expansion/improvements of the church (See Basin Map Exhibit in Appendix `C'). For pond design, 80% of the area was considered impervious and the remaining 20% was considered pervious. The areas used for pond design are as follows: Total Impervious to Pond = 148,177 sq. ft. (3.40 acres) Total Pervious to Pond = 37,044 sq. ft. (0.85 acres) The remainder of the area to be left as native, will continue to allow precipitation to be infiltrated. Performance Standards The 1992 Department of Ecology Stormwater Management Manual for Western Washington establishes the performance standards for all the storm drainage, infiltration and water quality facilities for the project. Flow Control System Flow control for the developed site will be mitigated via a retention pond located along the southern property of the parcel. (See Appendix `C') The pond is of a linear design and extends approximately the entire southern property line. An access ramp for the pond will be located on the western end with the pond inlet and control structure entering at approximately the middle of the pond. Access gates will be located for the ramp entrance and for access to the control structure. Based on infiltration testing for the site, a maximum infiltration rate of 60 in/hr is recommended by the geotechnical engineer. (See Appendix 'B') The maximum 5 short term infiltration rate per the DOEManual is 20 in/hr. With a safety factor of 2, the design, long term infiltration rate is 10 in/hr. The pond was designed using an infiltration rate of 10 in/hr. The pond was sized to infiltrate the runoff generated from the Tributary Area discussed above. The pond was designed utilizing the current Dept. of Ecology Western Washington Hydrology Model (WWHM) version 3 modeling software. With a design infiltration rate of 10 in/hr and effective depth of 6.5 ft., the minimum bottom surface area of the pond to achieve 100% infiltration of the Tributary Area is 1,960 sq. ft. The proposed pond has a bottom surface area of 2,756 sq. ft. The maximum water elevation in the proposed pond is approximately 2.75 ft. above the bottom elevation. See the Retention Pond Analysis in Appendix `C'. Water Quality Systems Water quality treatment will be performed on each of the lots and along the roadway. As such, there will be several different water quality basins that will treat the stormwater prior to connection to the storm drainage main that outlets to the pond. Lot 1 (Les Schwab) preliminarily has a precast Contech StormwaterSolutions 6'x12' StormFilter Vault with 10 - 18" cartridges. It will located just inside the southern most entrance to the site. See pages D1 -D4 in Appendix 'D' for sizing and specification information. The roadway is broken into two water quality basins, the northern half (RD1) and the southern half (RD2). Water quality treatment for RD1 and RD2 will preliminarily be handled by a Contech Stormwater Solutions 72" StormFilter Manhole and a 48" Stormfilter Manhole, respectfully. See pages D5 -D11 in Appendix `D' for sizing and specification information. Water quality treatment for any future improvements to Lot 2 will be contained within that specific future permit application. None are proposed at this time. Storm Drainage Conveyance Systems Conveyance calculations to ensure minimum cleaning velocity and adequate pipe sizing are included in Appendix 'E'. S.O DISCUSSION OF MINIMUM REQUIREMENTS The Minimum requirements for this project are set forth by 1992 Department of Ecology Stormwater Management Manual for Western Washington. See Figures 2.2 and 2.3 from the DOEManual in Appendix'A'. E Minimum requirements #1 through #10 apply to this project and are discussed below: #1 - Preparation of Stormwater Site Plans This storm water site plan satisfies this requirement. #2 - Construction Stormwater Pollution Prevention Plan (SWPPP) A Construction Stormwater Pollution Prevention Plan Short Form will be prepared and submitted in the civil plan review package. #3 - Source Control of Pollution Applicable Source Control BMPs will be employed as needed and will be located in the SWPPP and the Operations and Maintenance Manual as included in the civil plan review package. #4 - Preservation of Natural Drainage Systems and Outfalls The natural drainage of the site will be maintained by the use of infiltration. #5 - On-site Stormwater Management This requirement will be met by the use of infiltration for stormwater mitigation. #6 — Runoff Treatment See Section 4.0, Water Quality Systems within this report. #7 — Flow Control See Section 4.0, Flow Control System within this report. #8 — Wetlands Protection There are no known wetlands in the vicinity of the project site. #9 — Basin/Watershed Planning All requirements set forth by the DOEManua/and the City of Yelm Municipal Code have been adhered too. #10 — Operations and Maintenance An Operations and Maintenance Manual will be submitted in the civil plan review package. 7 APPENDIX A General Exhibits Thurston County Map Output Page Yelr Les Schwab Disclaimer' Thurston Coolly makes every e0bn to cost Ie that III mop is a it and acauate mp eserwroo of the \\ Or of County government. I ONyeN or, the County and el l relined personnel make no warranty, expressed or imp] led, regarding the accuracy. completeness or convenience ol'ally int ot'mation disclosed on this map. Nei does the Count accept lisbilip for any damage or iniury caused by the use ofthis map. In Ore losses( extent per pursuant to applicable law. I limstoo County disclaims all wamill(im express or implied, including, but not limited to, implied warmm es of merchant ability, data Gloess for o paNarlar pwpose, and nontinfringentelos of proprietaly rights. Under To, circumstances, including- hill not limited to, negligence, shall 'I hwstoo Colint} be liable for any direct, in(irect, incidental, special or consequential kroaLies that result from Ithe useof, or tile inability to lse 'Ihwstoo County matenalc Thurs(oit �r Sf 2009 - Thumtoo CounqOeoD Its Censer G eol)aia;? 2404 Heritage Court SW, 31 d Floor Cetricr .. Olympia, WA98502-6031 Page 1 of 1 LEGEND /N/ Major Roads y Flood Zones ^j Roads - Suter Bodies Strearus `l { r zoning I, - -J Contours Wetlands Cities Wetland Buffers Parcels http://geomapl.geodata.org/servlet/coin.esri.esrimap.Esrimap?ServiceName=cadastralov&... 11/9/2009 n i Thurston County Map Output Page elm Les Schwab 10210 Disc Imme.e'fharston Count, males even, elPort to ensure that this map is a true mid accumte Ieprescntalloft of the cem'k of County eorernment. I-Io6'e,Cl', the COMM -and ell mlmed pet Fennel make no \,artamn expressed or implied, regarding the accuYocy. completeness or Coll, enicnce of any infomtation disclosed on this map_ Nor does the Comity accept habilns f0i any dileltile onnuuy CsL1Scd h) file use ofthis map. 'lo file illicit eUurt ocimismwe pun'uamt to applicable hw- "Ihurstmt Comity disclaims all osm ilties espies or implied, inJudimg, but not limited to, implied mamm�ics ofinerchmv ability dam fitness to LL pamckilm purpose, mid non -i ih mgcancnts of propnetan, right'. Under no circumstances, imcluding, but not limited to, negliglence_ shall Thurston County Ise liable for any direct, indirect. iocideml, special or consequential damaaes that result from rhe useof- or the inability to usc. I hurston County materials. 'Yhms4ou 0 2009 - 1 hursfoo County GcoDma Colter Gei)Datit 2404 Heritage Cour[ SW, 3rd Flow Gamer Olympia, WA 98502-6031 Page I of I LEGEND /N,/ Major Roads Flood Zones Roads -,- 1hTdYPS Bodies streams Zoning Contours l Wetlands n _ Cities Wetland Buffers Parcels http://geomapl.goodata.org/servlet/eom.esri.esrimap.Esiimap?ScrviceName=cadastralov&... 11/9/2009 ^-2— Start Here Does the site have Yes See Redevelopment 35% or more of All Minimummore Minimum existing impervious or new plus replaced Requirements and coverage? surfaces and converted Flow Chart pervious surfaces. Does the project convert (Figure 2.3) No 3/A acres or more of native vegetation to lawn or Does the project add No landscaped areas, or 5,000 square feet or convert 2.5 acres or more more of new 10 of native vegetation to impervious surfaces? pasture? Yes Yes No Minimum Does the project have ® 2,000 square feet or All Minimummore of new, replaced, Requirements apply to or new plus replaced the new impervious impervious surfaces? surfaces and converted No pervious surfaces. Yes No Minimum Does the project have Requirements 41 land -disturbing through 45 apply toactivities of 7,000 the new and replaced Yes square feet or more? impervious surfaces and the land disturbed. No See Minimum Requirement S12, Construction Stormwater Pollution Prevention Figure 2.2 — Flow Chart for Determining Requirements for New Development February 2005 Volume I — Minimum Technical Requirements 2-9 A� 2-10 Do the new, replaced, or new plus replaced impervious surfaces total 2,000 square feet or more? OR Does the land disturbing activity total 7,000 square feet or more? Yes i No Mininmm Requirements #1 through #5 apply to the new and replaced impervious surfaces and the land disturbed. Next Question Apply Minimum Requirement #2, Construction Stormwater Pollution Prevention - Does the project add 5,000 square feet or more of new impervious surfaces? OR Convert 1/4 acres or more of native vegetation to lawn or landscaped areas? OR Convert 2.5 acres or more of native vegetation to pasture? Yes No Next Mininumt Requirements #1 through #10 Question Is this a road - apply to the new, impervious surfaces and related project? the converted pervious surfaces. Yes No Does the project add 5,000 square feet or more of new impervious surfaces? Yes Do new impervious surfaces add 50% or mare to the existing impervious surfaces within the project limits? No Yes No additional No 7s the total of the new plus replaced impervious surfaces 5,000 square feet or more, AND does the value of the proposed improvements — including interior improvements— exceed 50% of the assessed value (or replacement value) of the existing site improvements? Yes No No additional Minimum Requirements #1 through 1/10 apply to the new and replaced impervious surfaces. Figure 2.3 — Flow Chart for Determining Requirements for Redevelopment i Volume / — Minimum Technical Requirements February 2005 A9 Geotechnical Report Ph.253-896-1011 Fx.253-638-8992 Les Schwab Tire Centers c/o Contour Engineering 330956 1h Street NW Gig Harbor, WA 98359 Attn: Mr, Brett Allen, PE GeoResources, LLC 5113 Pacific Hwy. E, Ste. 1-1 Fife, Washington 98424-2649 August 12, 2009 Geotechnical Engineering Report Les Schwab Facility 805 East Yelm Avenue Yelm, Washington No: LesSchwab.YelmAve.RG INTRODUCTION This report presents the results of our geotechnical services for the proposed Les Schwab Tire Center commercial development at 805 East Yelm Avenue in Yelm, Washington. The location of the site is illustrated on the Vicinity Map, Figure 1. This report provides geotechnical recommendations and design criteria for the proposed site development. We further understand that stormwater infiltration systems are proposed for the development. The proposed site layout is illustrated on the Site Plan, Figure 2. Our services are provided at your request. Our understanding of the project is based on our discussions with you, our previous work in the area and our site observations and explorations. The purpose of our services is to evaluate the subsurface conditions at the site to determine geotechnical recommendations and design criteria, including stormwater infiltration rates. Specifically, our scope of services includes the following: 1. Review the available geologic, soil and ground water data relevant to the site. 2. Conduct a geologic reconnaissance of the site area. Monitor the excavation of trackhoe test pits across the site, and specifically in the area of the proposed infiltration systems.Collecting select soil samples for laboratory testing, as appropriate. 3. Providing geotechnical recommendations for site grading including site preparation, subgrade preparation, fill placement criteria, suitability of on- site soils for use as structural fill, temporary and permanent cut and fill slopes, drainage and erosion control measures. 4. Providing recommendations and design criteria for foundation elements and floor/driveway slab support, including allowable bearing capacity, subgrade modulus, lateral resistance valuesand estimates of settlement. 5. Providing recommendations and design criteria for conventional subgrade/retaining (basement) walls, including backfill and drainage requirements, lateral design loads, and lateral resistance values. Providing pavement subgrade recommendation for the plat roadway. 'bl Les Schwab — Yelm Avenue August 12, 2009 Page 2 6. Providing stormwater infiltration rates for the native soils at the proposed locations of the stormwater infiltration systems based on the City of Yelm regulations per Table 1, Soil Classification Table. SITE CONDITIONS Surface Conditions The project site is located in the central portion of the Yelm glacial outwash plain. The site is bounded by existing commercial development on the southeast and west, and Yelm Avenue on the north. We understand that the site is currently owned by the adjacent church (west), but will be subdivided for the proposed commercial development. The east portion of the site was previously developed as a residential site. The residence remains at the site but will be removed. In addition, the garage slab, fence, well house and timber storage building in the central portion of the site will be removed. There are also several concrete slabs utilized as play areas in the south portion of the site that will likely be removed. The ground surface at the site is generally flat. No surface water flow was observed at the site at the time of our reconnaissance. The site is currently vegetated with scattered shrubs, several large trees and ornamental grass. Site Geologic Conditions The site is situated in the central portion of the Yelm glacial outwash plain. The existing topography, as well as the surficial and shallow subsurface soils in the area are the result of the most recent Vashon stade of the Fraser glaciation that occurred between about 12,000 and 15,000 years ago, and the subsequent weathering and erosion. A description of the surficial soils is included in the "Site Soils" section of this report. In general the site is underlain by Vashon glacial outwash. The recessional outwash material consists of gravelly sand with cobbles and occasional boulders, and minor silt. The outwash material is in a medium dense condition near the surface to a depth of approximately 2 feet. The soils become dense below that depth. Based on our experience in the area, we expect that the site area is underlain by glacial till at depth, likely several 10s of feet. Site Soils The NCRS - SCS (Thurston County Soil Conservation Survey) has mapped the soils in the site area as Spanaway gravelly sandy loam (110) and Spanaway stony sandy loam (112). Both these soils are described as having a rapid permeability with a "slight' erosion hazard. We observed no active erosion in the site area during our reconnaissance. Based on our observations, the site soils appear to have little or no susceptibility to erosion, particularly where vegetation is established. Subsurface Conditions The subsurface conditions in the site area were evaluated by reviewing the geologic maps and previous geotechnical reports in the site area, and monitoring test pits excavated across the site and in the proposed infiltration areas. in general, recessional outwash sandy gravel was encountered to the full depth explored in the test pit explorations, up to 14.0 feet. The outwash material consisted of sandy gravel with cobbles and occasional boulders. The soil classification method used is included as Figure 4. Copies of the test pit logs area are included Figure S. Based on our site observations and experience, the soils at the site are generally consistent. Therefore, no additional subsurface explorations or borings are required. S2— Les Schwab —Yelm Avenue August12,2009 Page 3 Grain size tests were performed on soil samples collected below the bottom of the proposed infiltration system. The grain size tests indicate the soils are poorly graded gravel with sand (GP). Copies of the grain size tests are included in Appendix A. CONCLUSIONS AND RECOMMENDATIONS GENERAL Based on our site observations, explorations and analyses, we conclude that the site is suitable for the proposed commercial site development. It is also our opinion that the native site soils are suitable for the infiltration of stormwater, provided the recommendations and design criteria provided herein area followed. The site-specific soils at the proposed depth of the infiltration system and below a minimum of three feet consist of sandy gravel with cobbles and boulders and minor silt. These Type A soils will allow infiltration of stormwater from both the paved areas and the roof areas of the structures. Based on the soils encountered in the subsurface explorations at the site and our understanding of the proposed site development, conventional earthwork and foundation support is feasible for the project. Pertinent conclusions and geotechnical recommendations regarding the design and construction of the proposed development are presented below. Landslide Hazards No slopes over 15 percent occur at the site. No evidence of soil movement was observed at the site. Erosion Hazards Erosion hazard areas are defined by the City of Yelm as those areas defined by the USDA Soil Conservation Service (SCS) soil survey maps as having a "moderate to severe", "severe", or "very severe" rill and inter -rill erosion hazard. The subject property is located in an area mapped by the SCS as Spanaway stoney and gravelly sandy loam (112 and 116). It is our opinion that any potential erosion hazard of the site soils during site development is not a limiting factor for the proposed development. Temporary and permanent erosion control measures should be installed and maintained during construction or as soon as practical thereafter to limit the influx of additional water to exposed or disturbed areas. Erosion control measures may include, but should not be limited to, berms and swales with check dams to direct surface water runoff, ground cover/protection in exposed areas and silt fences where appropriate. Graded areas should be shaped to avoid concentrations of runoff onto cut or fill slopes, natural slopes or other erosion - sensitive areas. Temporary ground cover/protection such as jute matting, excelsior matting, wood chips or clear plastic sheeting may be used until the permanent erosion protection is established. Seismic Hazards According to the Seismic Zone Map of the United States contained in Figure 16-2 of the 1997 UBC (Uniform Building Code) and IBC (International Building Code), the project site is located within Seismic Risk Zone 3. Based on the subsurface conditions observed at the site, we interpret the structural site conditions to corresponds with a seismic Soil Profile type Se, (Site Class "C") as defined by Table 16-J 7JBC) and Table 1615.1.1 in the 2003 IBC documents, respectively. This is based on the likely range of equivalent SPT (Standard Penetration Test) blow counts for the soil types observed in the site area. These conditions were assumed to be representative for the conditions beyond the Les Schwab — Yelm Avenue August12,2009 Page 4 depths explored. Structures located at the site that are constructed in accordance with the appropriate seismic criteria will have the same risk as other designed structures in the Puget Sound area. High Groundwater Hazards The subject site is located outside of the Thurston County High Groundwater Hazard area. A copy of the Thurston County Data Center High Groundwater Map for the area is included as Figure 6. EARTHWORK RECOMMENDATIONS The following section of this report addresses our general conclusions and recommendations regarding site preparation, structural fill, and the re -use of onsite soils. Site Preparation Areas at the site to be graded should be cleared of deleterious matter including any existing structures, foundations, abandoned utility lines, debris and vegetation. The portions of the site still covered with vegetation should be stripped of any organic -laden soils. We anticipate that the average stripping depths will be on the order of 6 to 12 inches, although we expect that areas of deeper organics and topsoil will be encountered in the east portion of the site, up to 2 feet locally. The stripped topsoil may be stockpiled and later used for erosion control and landscaping/revegetation. Materials that cannot be used for landscaping or erosion control should be removed from the project site. Below the organic material and topsoil, there will be a layer of black sand and gravel with variable silt content. This material is commonly referred to as the Steilacoom Gravel. Although it is suitable for use as structural fill with the appropriate moisture content, it is moisture sensitive and difficult to work with during wet weather conditions. Where placement of fill material is required, the stripped/exposed subgrade areas should be compacted to a firm and unyielding surface prior to placement of any fill. We recommend that trees be removed by overturning in fill areas so that a majority of the roots are removed. Excavations for tree stump removal should be backfilled with structural fill compacted to the densities described in the Structural Fill section of this report. We recommend that a member of our staff evaluate the exposed subgrade conditions after removal of vegetation and topsoil stripping is completed and prior to placement of structural fill. The exposed subgrade soil should be proofrolled with heavy rubber -tired equipment during dry weather or probed with a 1/2 -inch -diameter steel rod during wet weather conditions. Any soft, loose or otherwise unsuitable areas delineated during proof rolling or probing should be recompacted, if practical, or over -excavated and replaced with structural fill, based on the recommendations of our site representative. Structural Fill All material placed as fill associated with mass grading or as utility trench backfill should be placed as structural fill. The structural fill should be placed in horizontal lifts of appropriate thickness to allow adequate and uniform comi'action of each lift. Fill should be compacted to at least 95 percent of MDD (maximum dry density as determined in accordance with ASTM D-1557). �3y Les Schwab — Yeim Avenue August12,2009 Page 5 The appropriate lift thickness will depend on the fill characteristics and compaction equipment used. We recommend that the appropriate lift thickness be evaluated by our field representative during construction. We recommend that our representative be present during site grading activities to observe the work and perform field density tests. The suitability of material for use as structural fill will depend on the gradation and moisture content of the soil. As the amount of fines (material passing US No. 200 sieve) increases, soil becomes increasingly sensitive to small changes in moisture content and adequate compaction becomes more difficult to achieve. During wet weather, we recommend use of well -graded sand and gravel with less than 5 percent (by weight) passing the US No. 200 sieve based on that fraction passing the 3/4 -inch sieve. If prolonged dry weather prevails during the earthwork and foundation installation phase of construction, higher fines content (up to 10 to 12 percent) will be acceptable. Material placed for structural fill should be free of debris, organic matter, trash and cobbles greater than 6 -inches in diameter. The moisture content of the fill material should be adjusted as necessary for proper compaction. Suitability of On -Site Materials as Fill During dry weather construction, any nonorganic on-site soil may be considered for use as structural fill; provided it meets the criteria described above in the structural fill section and can be compacted as recommended. If the material is over -optimum moisture content when excavated, it will be necessary to aerate or dry the soil prior to placement as structural fill. We generally did not observe the site soils to be excessively moist at the time of our subsurface exploration program. As discussed above, the near surface Steilacoom gravel materials have a high fines content and are moisture sensitive. During wet weather conditions, special consideration will be required to utilized these soils as structural fill. The underlying soils at the site generally consist of a fine to coarse sand with gravel, cobbles and boulders. These soils are generally comparable to "common borrow" material and will be suitable for use as structural fill provided the moisture content is maintained within 4 percent of the optimum moisture content. However, the outwash does appear to have a significant amount of cobbles and boulders, which may require removal in the upper two feet of fill. Care should be taken when placing and compacting granular material that has individual particales over 3 inches near utility lines and immediately below pavement surfaces. All fill material in building and driveway areas should be placed as described in the "Structural Fill" section of this report and compacted to at least 95 percent of the MDD. If fill material is imported to the site for wet weather construction, we recommend that it be clean sand and gravel mixture, such as high quality pit run with less than 5 percent fines, or crushed rock. Cut and Fill Slopes All job site safety issues and precautions are the responsibility of the contractor providing services/work. The following cut/fill slope guidelines are provided for planning purposes only. Temporary cut slopes will likely be necessary during grading operations or utility installation. As a general guide, temporary slopes of 1.51-n V (Horizontal:Vertical) or flatter may be used for temporary cuts in the upper 3 to 4 feet of the soils that are weathered to a loose/medium dense condition. Where ground water seepage is encountered, flatter temporary slopes may be required. These guidelines assume that all BT Les Schwab —Yelm Avenue August12,2009 Page 6 surface loads are kept at a minimum distance of at least one half the depth of the cut away from the top of the slope and that significant seepage is not present on the slope face. Flatter cut slopes will be necessary where significant raveling or seepage occurs. We recommend a maximum slope of 2H:1 V for permanent cut and fill slopes in areas of medium dense sand and gravel. Where 2H:1 V slopes are not feasible in these soils, retaining structures should be considered. Where retaining structures are greater than 4 -feet in height (bottom of footing to top of structure) or have slopes of greater than 15 percent above them, they should be engineered. It should be recognized that slopes of this nature do ravel and require occasional maintenance. Where raveling or maintenance is unacceptable, we recommend that flatter slopes or retaining systems be considered. GEOTECHNICAL DESIGN CRITERIA Foundation Support Based on the encountered subsurface soil conditions encountered across the site, we recommend that spread footings for the new residences be founded on medium dense native outwash soils or on structural fill that extends to suitable native soils. The soil at the base of the excavations should be disturbed as little as possible. All loose, soft or unsuitable material should be removed or recompacted, as appropriate. A representative from our firm should observe the foundation excavations to determine if suitable bearing surfaces have been prepared, particularly in the areas where the foundation will be situated in fill material. We recommend a minimum width of 2 feet for isolated footings and at least 16 inches for continuous wall footings. All footing elements should be embedded at least 18 inches below grade for frost protection. Footings founded on the shallow black silty sand and gravel as described above can be designed using an allowable soil bearing capacity of 2,000 psf (pounds per square foot) for combined dead and long-term live loads. Where footings extend to and are founded on the underlying gravelly sand, they can be designed using an allowable soil bearing capacity of 3,000 psf for the combined dead and long-term live loads. The weight of the footing and any overlying backfill may be neglected. The allowable bearing value may be increased by one-third for transient loads such as those induced by seismic events or wind loads. Lateral loads may be resisted by friction on the base of footings and floor slabs and as passive pressure on the sides of footings. We recommend that an allowable coefficient of friction of 0.40 be used to calculate friction between the concrete and the underlying soil. Passive pressure may be determined using an allowable equivalent fluid density of 350 pcf (pounds per cubic foot). Factors of safety have been applied to these values. We estimate that settlements of footings designed and constructed as recommended will be less than 1 inch, for the anticipated load conditions, with differential' settlements between comparably loaded footings of 1/2 inch or less. Most of the settlements should occur essentially as loads are being applied. However, disturbance of the foundation subgrade during construction could result in larger settlements than predicted. Floor Slab Support Slabs -on -grade, if constructed, should be supportel on the medium dense native outwash soils or on structural fill prepared as described above. We recommend that floor slabs be directly underlain by a capillary break material with minimum 6 -inch thickness of 30 Les Schwab — Yelm Avenue August 12, 2009 Page 7 coarse sand, pea gravel, or gravel containing less than 3 percent fines. The drainage material should be placed in one lift and compacted to an unyielding condition. A synthetic vapor barrier is recommended to control moisture migration through the slabs. This is of particular importance where the foundation elements are underlain by the silty till or lake sediments, or where moisture migration through the slab is an issue, such as where adhesives are used to anchor carpet or tile to the slab. A thin layer of sand may be placed over the vapor barrier and immediately below the slab to protect the liner during steel and/or concrete placement. A subgrade modulus of 400 kcf (kips per cubic foot) may be used for floor slab design. We estimate that settlement of the floor slabs designed and constructed as recommended, will be 1/2 inch or less over a span of 50 feet. Pavement and Driveway Areas We understand that asphalt pavements will be used for the new driveways and parking areas. All structural fill should be compacted according to our recommendations given in the "Structural Fill" section. Specifically, the upper 2 feet of soils underlying pavement section should be compacted to at least 95 percent of ASTM: D-1557, and all soils below 2 feet should be compacted to at least 90 percent. The subgrade areas should be proof -rolled with a loaded dump truck or heavy compactor to verify that a firm and unyielding surface has been achieved. Any areas where this proof -rolling operation reveals soft, organic, or pumping soils at or closely beneath the pavement subgrade should be overexcavated to a maximum depth of 8 inches and replaced with a suitable structural fill material. DRAINAGE CONSIDERATIONS Stormwater Infiltration Rates Based on the soils encountered in our explorations and the results of the grain size tests, we conclude that the infiltration of storm water is feasible at the site. The thick underlying deposits of recessional outwash soils have adequate permeability and storage capacity to infiltrate storm water from the site, provided adequate design, construction and maintenance practices are used. Storm water infiltration rates for the site soils were determined in accordance with the Yelm/Thurston County Stormwater Manual guidelines, Table 1. Grain size distribution tests were performed on select soil samples collected from the depth of the proposed infiltration trench. The results of the grain size test are included in Appendix A. Based on the soils observed in the test pits excavated at the site's stormwater infiltration locations, we recommend a maximum infiltration rate of 60 inches per hour be used for the infiltration system to be located in the area of Test Pits 3 through 6. For the soils encountered in Test Pits 7 and 8 we recommend an infiltration rate of 40 inches per hour. We recommend an appropriate factor of safety be applied to these values. Typically, surface systems (ponds) utilize a factor of safety of 2, while a higher factor of safety should be utilized for a below grade system (gallery). Suspended solids could eventually clog the soil and reduce the infiltration rate for retention ponds or trenches. Because of the potential for clogging, we recommend that an appropriate factor of safety be utilized in the design. To reduce potential clogging of the infiltration systems, the infiltration ponds or galleries shouldaot be connected to the stormwater runoff system until after construction is complete and the site areas are landscaped and paved. Temporary systems may be utilized through construction, or the pond/trench bottom left a minimum of 1.5 -feet high during construction and later excavated to the design grade. Periodic sweeping of the paved areas will help extend the life of the S1 Les Schwab — Yelm Avenue August 12, 2009 Page 8 infiltration system. LIMITATIONS We have prepared this report for Les Schwab and project consultants for use in design and construction of the various components of this project. The data and report can be utilized for bidding or estimating purposes, but our report, conclusions and recommendations should not be construed as a warranty of the subsurface conditions, as they may vary both vertically and laterally. If there are changes in the locations or assumptions stated for this project, the conclusions and recommendations presented may not be fully applicable. If design changes are made, we should review the proposed changes to verify the applicability of our conclusions and recommendations. Variations in subsurface conditions are possible between the explorations and may also occur with time. Sufficient monitoring, testing and consultation should be provided by our firm during construction to confirm that the conditions encountered are consistent with those indicated by the explorations, to provide recommendations for design changes should the conditions revealed during the work differ from those antici- pated, and to evaluate whether earthwork and foundation installation activities comply with contract plans and specifications. Within the limitations of scope, schedule and budget, our services have been executed in accordance with generally accepted practices in this area at the time this report was prepared. No other conditions, expressed or implied, should be understood. ♦ ♦ O We appreciate the opportunity to be of service to you on this project. Please call if you have any questions regarding this submittal, or if we can provide additional services. Yours very truly, GeoResources, LLC Glen Coad, PE BPS:GGbpb DoclD:LesSch W ab.YelmAVe.RG ii Adad,l r ls: Figure site vwdy Map Figure 2 - Site Pan Figure $ • NRCS SCS Map Figure 4 - Soil Classification System Figure 5 - Test Prt Logs Figure 6— Thurston Cmnty High Groundwater Hazard Map AppondiK A— Grein Size Mali Brad P. Biggerstaff, LHG Principal IL LEY P. PacGERSTAw:1 s .RIS f. Av !A I H U R S T 0 N q. A, Pv oCcarars I 12 I Ito Ave SE ax i Ae L i A, Pv oCcarars I 12 I Ito Ave SE ax A, Cook RASE 4".1IM"4Y$E IMAwSE ax j -"I R GeoResources, LLC 5007 Pacific Highway East, Suite 20 Fife, Washington 98424 Phone: 253-896-1011 Fax: 253-896-2633 Approximate Site Location Not to Scale Site Vicinity Map Proposed Commercial Development 805 Yelm avenue SE Yelm, VVeshington - DocID: LesSchwab.Yelm�August 2009 Figure 1v,.SW rr �"r:i anew , f, I I t"si ,� i 9� TP -2m a rto ij cwuacr+ P -6i■ TP -3■ �y a r °- ! TP -5 ,1 C.\ TP -4 ■tM fn I t I Nrvrvou Anl4 \� plyy i .' J L _.. 9T2 PLAN � w _I '-------------- .._._`.___ SCALE 1" = 100' APPROXIMATE LOCATION AND NUMBER OF TEST PIT TP -1 ■ Site Plan Provided by Contour Engineering & prepared LS Construction Co. dated 8.01.2009 _ GeoResources, LLC Site Pian & Exploration Map 5007 Pacific Highway East, Suite 20 Proposed Commmcial Development Fife, Washington 98424 805 Yelm Avenue SE Phone: 253-896-1011 Ye m, Washin ton _ Fax: 253-896-2633 DocID: LesSchwab.YelmAve.SP August 2009 Figure 2 �I� Approximate Site Location SCS Soil Type SCS Soil Name Parent Material Slopes in ercent 74 _ _ Nisqually loamy fine sand Sandy Glacial Outwash 3 to 15 110 Spanaway gravelly sandy loam Volcanic ash over gravelly outwash 0 to 3 GeoResources, LLC 5007 Pacific Highway East, Suite 20 Fife, Washington 98424 Phone: 253-896-1011 Fax: 253-896-2633 NRCS Soils Map Proposed Commercial Development 805 Yelm Avenue SE Yelm,Washington DocID: LesSchwab.YelmAve.SCS I August 2009 Not to Scale Figure 3 U SOIL CLASSIFICATION SYSTEM MAJOR DIVISIONS GROUP GROUP NAME SYMBOL GRAVEL CLEAN GW WELL -GRADED GRAVEL, FINE TO COARSE .. GRAVEL GRAVEL .- _ COARSE GP POORLY -GRADED GRAVEL GRAINED More than 50% - — SOILS Of Coarse Fraction GRAVEL GM SILTY GRAVEL Retained on WITH FINES --- No. 4 Sieve - GC CLAYEY GRAVEL More than 50% SAND CLEAN SAND SW WELL -GRADED SAND, FINE TO COARSE SAND Retained on No. 200 Sieve SP POORLY -GRADED SAND More than 50% 'Of Coarse Fraction SAND SM SILTY SAND Passes WITH FINES ---- _. No.4 Sieve SC CLAYEY SAND .... SILT AND CLAY INORGANIC ML SILT CL -..._ CLAY FINE_:: � GRAINED - _... .. SOILS Liquid Limit Less than 50 ORGANIC OL ORGANIC SILT, ORGANIC CLAY SILT AND CLAY INORGANIC MH SILT OF HIGH PLASTICITY, ELASTIC SILT - . More than 50% Passes CH CLAY OF HIGH PLASTICITY, FAT CLAY No. 200 Sieve Liquid Limit 50 or more pRGANIC OH ORGANIC CLAY, ORGANIC SILT HIGHLY ORGANIC SOILS PT PEAT NOTES: 1... Field classification is based on visual examination of soil in general accordance with ASTM D2488-90. j 2. „ . Soil classification using laboratory tests Is based on ASTM Q24$7-90. 3. Description of soil density or consistency are based on interpretation of blow count data, visual appearance of soils, and or test data. SOIL MOISTURE MODIFIERS: Dry- Absence of moisture, dry to the touch Moist- Damp, but no visible water Wet- Visible free water or saturated, usually soil Is obtained from below water table GeoResources, LLC Soil Classification System 5007 Pacific Highway East, Suite 20 Proposed Commercial Development Fife, Washington.98424 805 Yelm Avenue SE Phone: 253-898.1011 Yeim, Washington -Fax' 253-896-2633 JOB LesSchwab.YelmAva August 2009 Figure 4 BIZ IW Test Pit TP-1 Location: NE portion of the site, by old house Depth (ft.) Soil Type Description 0.0- 1.0 Sod/Topsoil w/ sand and gravel 1.0-2.5 GM Brown silty GRAVEL with occ. cobbles (loose, moist) 2.5-5.0 SP Org/Brn SAND w/ gvl, cobbles, occ. boulders (med. dense to dense, moist) 6.0- 11.0 SP Brn gravelly SAND w/ cobbles, boulders (dense, moist) Terminated at 11.0 feet below ground surface. Minor caving observed. No groundwater seepage observed. Test Pit TP-2 Location: Behind old house, between shed Depth (ft) Soil Type Description 0.0-2.0 Sod/Topsoil. 2.0-2.5 GM Blk si GRAVEL w/ occ. cobbles (loose, moist) 2.5-9.5 SP Brn gravelly SAND w/ cobbles & boulders (med. dense to dense, moist) Terminated at 6.0 feet below the ground surface. Moderate caving observed at 6.0 feet below ground surface. No groundwater seepage observed. Test Pit TP-3 Location: NE corner of Playfield Depth (ft) Soil Type Description 0.0-1.5 Sod/Topsoil. 1.5-2.5 GM Blk si GRAVEL w/ occ. cobbles (loose, moist) 2.5-8.0 SP Brn gravelly SAND w/ cobbles & boulders (med. dense to dense, moist) 8.0- 14.0 GP Brn sdy/cobbly GRAVEL w/ occ. boulders (dense, moist) Terminated at 14.0 feet below the ground surface. Minor caving observed No groundwater seepage observed. GeoResources, LLC Test Pit Logs 5007 Pacific Highway East, Suite 20 Les Schwab Tires - Yeirn Avenue Fife, Washington 98424 Yeim1 Washington Phone: 253-896-1011 Fax: 253-896-2633 JOB: LesSohwab.YelmAve.TP Aug 2009 Figure 5 IW 31 lq Test Pit TP -4 Location: SE corner of Playground Depth (ft) Soil Type Description _ 0.0- 1.0 SodlTopsoil. 1.0- 1.5 SM Blk si SAND w/ gravel, occ. cobbles (loose, moist) 1.5 - 12.5 SP Brn gravelly SAND w/ cobbles & boulders (med. dense to dense) Terminated at 12.5 feet below the ground surface. Minor caving observed No groundwater seepage observed. Test Pit TP -5 Location: SW corner of Playground Depth (ft) Soil Type Description 0.0-0.5 Sod/Topsoil. 0.5- 1.0 GM Blk si GRAVEL w/ occ. cobbles (loose, moist) 1.0-15.0 SP Brn gravelly SAND w! cobbles & boulders (med. dense to dense) Terminated at 6.0 feet below the ground surface. Moderate caving observed at 6.0 feet below ground surface. No groundwater seepage observed. Test Pit TP -6 Location: NW corner of Playground Depth (ft) Soil Type Description 0.0-1.0 Sod(Topsoil. 1.0-2.0 SM Blk si SAND w/ gravel occ. cobbles (loose, moist) 2.0-6.0 SP Brn gravelly SAND w/ cobbles & occ. boulders (med. dense to dense) 6.0- 13.0 GP Brn sdy GRAVEL w/ cobbles, boulders (dense, moist) Terminated at 6.0 feet below the ground surface. Moderate caving observed at 6.0 feet below ground surface. No groundwater seepage observed. GeoResources, LLC Test Pit Logs 5007 Pacific Highway East, Suite 16 NW Corner Yelm Avenue SE & Creek Street Fife, Washington 98424 Yelm, Washington Phone: 253.896-1011 Fax: 253-896.2633 JOB: DevelopmentatYeim.YeimSCornersRetaii.TP May 2007 Figure 5 '.. 31 lq Test Pit TP -7 Location: Behind garage slab, next to tree Depth (ft) Soil Type Description 0.0-1.5 Sod/Topsoil. 1.5-2.6 SM Silk si SAND w/ occ. cobbles, organics (loose, moist) 2.5-5.0 SP Org/Brn gravelly SAND w/ cobbles & boulders (med. dense to dense) 5.0- 12.5 GP Brn sdy GRAVEL w/ cobbles & boulders (dense, moist) Terminated at 12.5 feet below the ground surface. Moderate caving observed No groundwater seepage observed. Test Pit TP -8 Location: East of church driveway, west part of site Depth (ft) Soil Type Description 0.0-0.5 Sod/Topsoil. 0.5.1.8 GM Blk si GRAVEL w/ occ. cobbles (loose, moist) 1.8-4.0 SP Brn SAND w/ gravel, cobbles & occ. boulders (med. dense to dense) 4.0-9.5 SP Gry SAND w/ gravel, cob & occ. boulders (dense, moist) 9.5-16.0 GP Gry/Brn gravelly SAND w/ cobbles & boulders (dense, moist) Terminated at 16.0 feet below the ground surface. Moderate caving observed No groundwater seepage observed. Test Pit TP -9 Location: NW corner of site, next to tree Depth (ft) Soil Type Description 0.0-1.0 Sod/Topsoil. 1.0-2,0 SM Blk si SAND w/ occ. cobbles, organics (loose, moist) 2.0 - 12.15 GP Brn sdy GRAVEL w/ cobbles & boulders (dense, moist) Terminated at 12.5 feet below the ground surface. Moderate caving observed No groundwater seepage observed. Logged by: BPB Date: Aug 2009 GeoResources, LLC Test Pit Logs 5007 Pacific Highway East, Suite 16 NW Corner Yelm Avenue SE & Creek Street Fife, Washington 98424 Yelm, Washington Phone: 253-896.1011 _ Fax: 253-896-2633 --- — J08: Les Schwab.YelmAve.TP Aug 2009 Figure 5 8)5 APPENDIX "A" SIEVE SIZE PERCENT " FINER SPEC.' PERCENT PASS? (X=NO) 2.5 100.0 2.0 _Particle Size Distributions Report 1.5 64.4 8 S 'x -.1.2.5- 63.0 1 56.0 Z u$ Z i v 46.6 100 39.1 .3125 36.4 #4 32.5 #10 30.4 #20 25.5 #40 9.6 -#60 3.2 #100 1.7 #200 1.0 80 70 so Z l LL j z so V LU - v I I I I I I I I V I I I w 40 - 1 + I - ..... _ 30 V I _ - 2a 1I( _ I IItill" Ii l I I I I I I I I N 100 10 1 0.1 0.01 c GRAIN SIZE - mm. c %Gravel %Sentl V. Fines p ° °' Coarse Fine Coarse Medium Fine Silt " .., 4) _ 0.0 1 53.4 1 14.1 1 2.1 1 20.8 1 8.6 1 1.0 SIEVE SIZE PERCENT " FINER SPEC.' PERCENT PASS? (X=NO) 2.5 100.0 2.0 80.7 1.5 64.4 -.1.2.5- 63.0 1 56.0 .75 46.6 .5 39.1 .3125 36.4 #4 32.5 #10 30.4 #20 25.5 #40 9.6 -#60 3.2 #100 1.7 #200 1.0 0 -.. 10 20 --- 30 40 -- 50 so 70 80 - 90 100 Material Description Sandy GRAVEL Sampled by BPB on 8/6/09 Tested by RMH on 8/7/09 Atterberg Limits PL= LL= P1= Coefficients D85= 53.5063 D60= 28.2286 D50= 21.4036 D80= 1.3754 D15= 0.5394 DiO= 0.4342 Cu= 65.02 Cc= 0.15 ' Classification USCS= GP AASHTO= Remarks F.M.=6.36 F -- specification provided) _ 2 p Sample Number: 090160 Depth: 12-15 feet depth m " Location. TP -8 Date: 8/10/09 ° Geollesources, LLQ Client: Les Schwab Store - Project: Proposed Commercial Developement 1 h - F1fe,_WA. " - Project No: LesSchwab.Yeltitffty Figure Tested By: RMH - _ Checked By: BPB__..,_ _ I - Gas APPENDIX C Retention Pond Analysis Western Washington Hydrology Mode]. PROJECT REPORT Project Name: 09-024.Lin Ret Pond Required Site Address: City Report Date :1./9/2009 Gage Olympia Data Start 1955/10/01 Data End 1.999/09/30 Precip Scale: 0.80 WWH43 Version: DEVELOPED LAND USE Name Pond Bypass: No Groundwater: No Pervious Land Use Acres C, Lawn, Flat .65 Impervious Land Use Acres PARKING FLAT 3.4 Element Flows To: Surface Interflow Groundwater Trapezoidal Pond 1, Trapezoidal Pond 1., Name Trapezoidal Pond 1 _ 6 Bottom Length: 196ft. R tioi�°✓vl F Bottom Width: i0ft. Depth : 6.5f.t. Volume at riser head : 0.5638f.t. Infiltration On Infiltration rate 20 \� Infiltration saftey factor 0.5.x_ Side slope 1: 2 To 1 Side slope 2: 2 To 1 Side slope 3: 2 To 1 Side slope 4: 2 To 1. Discharge Structure Riser Height: 5.5 ft. Riser Diameter: 1.8 in. Element Flows To: Outlet 1 Outlet 2 GZ- Pond Hydraulic Table Stage(ft) Area(acr) Volume(acr-ft) Dschrg(cfs) Infilt(cfs) 0.000 0.045 0.000 0.000 0.000 0.072 0.046 0.003 0.000 0.454 0.144 0.048 0.00'7 0.000 0.454 0.21.7 0.049 0.01.0 0.000 0.454 0.289 0.050 0.01.4 0.000 0.454 0.361 0.052_ 0.017 0.000 0.454 0.433 0.053 0.021. 0.000 0.454 0.506 0.055 0.025 0.000 0.454 0.578 0.056 0.029 0.000 0.454 0.650 0.057 0.033 0.000 0.454 0.722 0.059 0.037 0.000 0.454 0.794 0.060 0.042 0.000 0.454 0.867 0.062 0.046 0.000 0.454 0.939 0.063 0.051. 0.000 0.454 1.011 0.064 0.055 0.000 0.454 1.083 0.066 0.060 0.000 0.454 1..156 0.067 0.065 0.000 0.454 1.228 0.069 0.070 0.000 0.454 1.300 0.070 0.075 0.000 0.454 1.372 0.072 0.080 0.000 0.454 1.444 0.073 0.085 0.000 0.454 1.517 0.075 0.090 0.000 0.454 1.589 0.076 0.096 0.000 0.454 1.661 0.077 0.1.01 0.000 0.454 1.733 0.079 0.107 0.000 0.454 1.806 0.080 0.113 0.000 0.454 1.878 0.082 0.119 0.000 0.454 1.950 0.083 0.125 0.000 0.454 2.022. 0.085 0.131 0.000 0.454 2.094 0.086 0.137 0.000 0.454 2.167 0.088 0.143 0.000 0.454 2.239 0.089 0.150 0.000 0.454 2.311 0.091 0.156 0.000 0.454 2.383 0.092 0.163 0.000 0.454 2.456 0.094 0.169 0.000 0.454 2.528 0.095 0.176 0.000 0.454 2.600 0.097 0.183 0.000 0.454 2.672 0.098 0.190 0.000 0.454 2.744 0.100 0.1.97 0.000 0.454 2.817 0.1.01 0.205 0.000 0.454 2.889 0.103 0.212 0.000 0.454 2.961 0.1.04 0.219 0.000 0.454 3.033 0.106 0.227 0.000 0.454 3.106 0.107 0.2.35 0.000 0.454 3.178 0.1.09 0.242 0.000 0.454 3.250 0.110 0.250 0.000 0.454 3.322 0.112 0.258 0.000 0.454 3.394 0.113 0.267 0.000 0.454 3.467 0. 115 0.275 0.000 0.454 3.539 0. 117 0.283 0.000 0.454 3.611. 0.1.18 0.292 0.000 0.454 3.683 0.1.20 0.300 0.000 0.454 3.756 0.1.21 0.309 0.000 0.454 3.828 0.123 0.318 0.000 0.454 3.900 0.124 0.327 0.000 0.454 3.972 0.126 0.336 0.000 0.454 4.044 0.128 0.345 0.000 0.454 4.117 0.129 0.354 0.000 0.454 G3 4.189 0.131 0. 363 0.000 5 year 0.454 4.261 0.132 0.3'73 1..3428 0.000 50 year 0.454 4.333 0.134 0.383 0.000 0.4:14 4.406 0.435 0.392 0.000 0.4514 4.478 0.;.37 0.402 0.000 0.454 4.550 0. 1.39 0.41.2 0.000 0.454 4.622 0.140 0.422 0.000 0.454 4.694 0.1.42 0.432 0.000 0.454 4.167 0.144 0.443 0.000 0.454 4.839 0.145 0.453 0.000 0.454 4.911 0.147 0.464 0.000 0.454 4.983 0.148 0.474 0.000 0.454 5.056 0.1.50 0"485 0.000 0.454 5.128 0.1.57. 0.496 0.000 0.454 5.200 0.153 0.50"1 0.000 0.454 5.272 0.155 0.51.8 0.000 0"454 5.344 0.151 0.529 0.000 0.454 5.417 0.158 0.541 0.000 0.454 5.489 0.160 0.552 0.000 0.454 5.561 0.1.62 0.564 0.221 0.454 5.633 0.1.63 0.576 0.71.1 0.454 5.706 0.165 0.587 1.361 0.454 5.778 0.1.67 0.599 2.139 0.454 5.850 0.168 0.611, 3.025 0.454 5.922 0.170 0.624 4.008 0.454 5.994 0.172 0.636 5.079 0.454 6.067 0.173 0.648 6.232 0.454 6.139 0.175 0.661 7.460 0.454 6.211 0.177 0.674 8.160 0.454 6.283 0.178 0.687 10.13 0.454 6.356 0.1.80 0.699 11.56 0.454 6.428 0.182 0.71.3 13.05 0.454 6.500 0.183 0.726 14.61 0.454 6.572 0.185 0.739 1.6.22 0.454 ANALYSIS RESULTS Flow Frequency Return Periods for Developed. POC #1 Return Period Flow(cfs) 2 year 0.8829 5 year 1.0769 10 year 1.1.9'73 25 year 1..3428 50 year 1..4475 100 year 1.5495 This program and accompanying documentation is provided 'as -is' without warranty of any kind. The entire risk regarding the performance and results of this program is assumed by the user. Clear Creek Solutions and the Washington State Department of Ecology disclaims all warranties, either expressed or implied, including but not limited to implied warranties of program and accompanying documentation. In no event shall Clear Creek Solutions and/or the Washington State Department of Ecology be liable for any damages whatsoever (including without limitation to damages for loss of business profits, Loss of business .i.nformation, business interruption, and the like) arising out of the use of, or .inability to use this program even if Clear Creek Solutions or the Washington State Department of Ecology has been advised of the possibility of such damages. (, 114 APPENDIX D Water Quality Systems Sizing and Specifications 1 el v- i %.MAS /'5- - f(ov (cin ` 0,154 7 6 7, 7 .� .i yrs SSG sdt_ - 7� �- lode.( 5�� r✓ — /S 5�/ i e / o?u i �l.f� ..S- - �7 4' `>-I.�`7� ' - /,� 7� l 5F' _ �Y `t7' I I � (�� :J�i` Gi:✓e) 117,5 /5F' �iSG 5(= of 13SS (C'Z3QG:e5� 1 el v- i %.MAS /'5- - f(ov (cin ` 0,154 7 6 7, 7 Western Washington Hydrology Model PROJECT REPORT Project Name: Site Address: City Report Date Gage Data Start Data End Precip Scale: WWH43 Version: 09-024.WQ BASIN SCHWAB 1.0/28/2009 Olympia 1955/10/01 1.999/09/30 0.80 Name SCHWAB Bypass: No GroundWater: NO Pervious Land Use Acres C, Lawn, Flat .23 Impervious Land Use Acres PARKING FLAT 1.03 Element Flows To Surface Interflow Groundwater Water Quality SMP Flow and Volume for POC 1. On-line facility volume: 0.1421 acre-feet On-line facility target flow: 0.01 cfs. / Adjusted for 15 min: 0.1587 cfs. t (Avp f --Ir Off-line facility target flow: 0.0806 cfs Adjusted for 15 min: 0.0892 cfs. This program and accompanying documentation is provided 'as -is' without warranty of any kind. The entire risk regarding the performance and results of this program is assumed by the user. Clear Creek Solutions and the Washington State Department of Ecology disclaims a1.1warranties, either expressed or implied, including but not l.i.mi.ted to implied warranties of program and accompanying documentation. In no event shall Clear Creek Solutions and/or the Washington State Department of Ecology be liable for any damages whatsoever (including without limitation to damages for loss of business profits, loss of business information, business interruption, and the like) arising out of the use of, or. inability to use this program even if Clear Creek Solutions or the Washington State Department of Ecology has been advised of the possibility of such damages. g2_ bAIAJIST .O -AI ION PIPE (`iEE NOT[ 15) LocnTION (TYP) (SEE NOI E 6) OUILF1 RAY INLE1 PIPE _� + OUTLET PIPE (5EE NOTES 546) (5EE NOTE5 5£G 6'x 12' STORMFILTER - PLAN VIEW rl 30'0 PRAMS AND COVER (TYP) (5EE NOTE 4) GRADE. RING ((Yr) FLOW SPREADER 1 (TYP) P.AFPLF Y✓Alt. (TYP) FF I LADDER 4'-G' MIN (SEE NOTE 7) 3'-4 PERMANENT POOL 11 it lilt i t ENERGY 5TORMFILTFR D1551PA1 OR CARTRIDGE. (TYP) UNDERDRAIN (HE NOTE 2) MANIPOI.D 6' x 12' STORMFILTER-SECTION VIEW Dif 51ORMWAUR MANAGZWNT 5[onN 1 LlS.PAIFN2Plo.o. 53 5.322.629. Nc..707.529, N, 6A27,639 NAND 649,OAb. No. 5.FOUIG6, /JJD OTNF.R U.S. ANG FOREIGN (92006 CONTECH Stonwater Solutions PATfNT5 Penowc 6' x 12' PRECAST STORMFILTER DR WING STORMWATER PLAN AND SECTION VIEWS � SOLUTIONS STANDARD DETAIL 112 Wntehatomwaler.wm DATE: 09129105 1 SCAT H: NONE I FILE NAME: 5F61bPC4XL OfNWN:MAV CHECRL):PRC V J GENERAL NOTE5 I) 5TORMPILTER BY CONTECH STOPMWATEP. 501UTIONS; PORTLAND, OR (800) 548-4667; 5CA.PROR000t', M(_ (877) 907 8G7G; E.LKPJDGE, MD (8GG) 740.3 18. 2) FILTER CARTRIDGE(-,) TO DE SIPHON -ACTUATED AMC) 511L1 -CLEANING. 51ANDAR,D DETAIL DPAWING 5HOW5 MAXIMUM NUMI3LR OF CARTRIDGEr, ACTUAL NUMBER REQUIRED TO RE SPECIFIED ON 51T'E PLANS OR IN DATA TABLE BELOW. 3) PRECAST VAULT TO HE CONSTRUCTED IN ACCORDANCE tNlTfi ASTM C857 AND 0858. DETAIL DRAWING REFLECTS DESIGN IIJTENT ONLY. ACTLJAI. DMENSIOWS ANO CONFIGURATIOIJ OF .STRUCTURE WILT. RE SHOWN ON PRODUCTION SHOE DRP.WING. 4) STRUCTURE. ANC ACCESS COVERS TO MEET AASrrO tf20 LOAD RATING. 5) 5TORMEII.TCR REQUIRE-, 2.3 FEET OP DROP FROM INLET TO OUTI.ET. IF LESS DROP IS AVP.IIAI3LC-, CONTACT CONTECY, 5TORMWATER 50(UTION5, G) INLET ANC OUFF1 FIRING i0 BF 5PFCIPIED BY ENGINEER AND PROVIIJED by CONTWP.CTOR. PRECAST 5TORMFILTFR VAUIT FQUIPPED WITH EITHER CORED OPENINGS OR ICNOCICOU15 AT [NJ FI AND OUTLT LOCANON5. 7) PROVIDE MINIMUM CI EARANCE POR MA.INTENlWCE ACCESS. If A 51-11,I.I.OWER 5Y5TE M: IS REQUIRED, CONTACT CONTECH 5TORMWATEP 5OLUTIONS POR OTYER OPTIONS. 5) ANTI -FLOTATION 3AIIA5T TO BE 51'EQFIED BY ENGINEER AND PPOVIDED BY CONTRACTOR, IF REQUIRED, RAJ I AiT TO EC 5117 ALONG ENTIRE LENGTH OF BOTH 51DE5 Of THE 5TRUCTUPE. 9) AL15TORMFILTER5 REQUIRE REGU[AR MAINTENANCE, REFER TO OPERATION AND MAINTENA.NCE GUIDELINE5 FOR MORE RAF BE fl/A11 30'0 FRAME AND COVER (TYP) (SEE 140TE 4) FLOW SPREADER BALLAST (SIFE NOTE 8) HEIGHT e + UNDERORAIN MANIFOLD WIDTH��--) 6'x 12' STORMFILTER - SECTION VIEW rBS-� 2 W'3 6' x 12' STORMFILTER -TOP VIEW 2 RfP STOR�n1VA'fFl2 MANAG[MCNT $R:crxJ 0.5. PATENTNT 11nlo. 5,322.629, No. D.707.e27, No. e.027o39 AND OTfiPB U.S. AND FOREIGN PhiZNt$ WUNDING �/=��i�SITCAIJ� 6'x 12' PRECAST STORMFILTER V�� i TOP VIEW, SECTION VIEW AND NOTES 2 STORMWATER�----� STANDARD DETAIL �---�SOLUTIONS v2 wntechstormvmter,wm DATE.09I26I05 I SCALE:NONE I I ILE NAML:SF612.PC-DTL DHAV✓N: MJW I CHE:CKED;ARG V�y r w /.ti =�� J i� oil -02-y 2 SF 0;LICJS— Iffier✓'. ;; ,;c .�-rte.. = f:Xv35i= x"L = 2. 73'� ,5�..�per✓:jos rr_ = 1710 Z-7 iLiU2- 5F �U(, '3``iZ Gc✓c) �%✓ (,JG✓{�/�� iS-rn�h �%e.✓ R �- = C�,��SzB c -ice AID rAre pe ✓;a✓y f�v c- _ l�lv� f - a'tiS = l"zh YJo �11 � WC/i I-I/✓i /S r�� -F/e.✓ &w c = 0.0>1'13 ci's 7 C�Oly3 K `l49 = Z.�"3 '—' 3c�r 5ey ��S�MIf' Western Washington Hydrology Model PROJECT REPORT Project Name: Site Address: city Report Date Gage Data Start Data End Precip Scale: WWHIf3 Version: 09-024.WQ BASIN ;pRDl 11/4/2009 Olympia 1955/10/01 1999/09/30 0.80 Name RD1 Bypass: No GroundWater: NO Pervious Land Use Acres C, Lawn, Flat .063 Impervious Land Use Acres ROADS FLAT 0.342 Element Flows To: Surface Interflow Groundwater Water Quality BMP Flow and Volume for POC 1. On-line facility volume: 0.0469 acre-feet e On-line facility target flow: 0.01 efs. U eck For slZ,In Adjusted for 15 min: 0.0528 cfs. <_- J Off-line facility target flow: 0.0267 efs. Adjusted for 15 min: 0.0296 cfs. This program and accompanying documentation is provided 'as -is' without warranty of any Kind. The entire risk regarding the performance and results of this program is assumed by the user. Clear Creek Solutions and the IJashington State Department of Ecology disclaims all warranties, either expressed or implied, including but not limited to implied warranties of program and accompanying documentation. in no event shall Clear Creek Solutions and/or the Washington State Department of Ecology be liable for any damages whatsoever (including without limitation to damages for loss of business profits, loss of business information, business interruption, and the Like) arising out of the use of, or inability to use this program even if Clear Creek Solutions or the Washington State Department of Ecology has been advised of the possibility of such damages. D(o Western Washington Hydrology Model PROJECT REPORT Project Name: Site Address: City Report Date Gage Data Start Data End Precip Scale: WWHM3 Version: 09-024.4gQ BASIN IIRD2 7.1/4/2009 Olympia 1955/10/01 1999/09/30 0.80 Name RD2 Bypass: No GroundWater: No Pervious Land Use Acres C, Lawn, Flat .044 Impervious Land Use Acres ROADS FLAT 0.287 Element Flows To: Surface Interflow Groundwater Water Quality li+ Flow and Volume for POC 1. On-line facility volume: 0.039 acre-feet On-line facility target flow: 0.01 cfs. Adjusted for 15 min: 0.0443 cfs. _< (Ac, S� 2'n� Off-line facility target flow: 0.0224 cfs. Adjusted for 15 min: 0.0249 cfs. This program and accompanying documentation is provided 'as -is' without warranty of any kind. The entire risk regarding the performance and results of this program is assumed by the user. Clear Creek Solutions and the Washington State Department of Ecology disclaims all warranties, either expressed or implied, including but not limited to implied warranties of program and accompanying documentation. In no event shall Clear Creek Solutions and/or the Washington State Department of Ecology be liable for any damages whatsoever (including without limitation to damages for loss of business profits, loss of business information, business interruption, and the like) arising out of the use of, or inability to use this program even .if Clear. Creek Solutions or the Washington State Department of Ecology ties been advised of the possibility of such damages. D-7 64.1.1:.51 ° (5EE NOTE 8) 7Z''O ° A 1 INLET PIPE 5'71 2'0 I1DPE OUTLET (5EE NOTE5 5 E G) 5TUD (5EE NOTE5 5 G) n MANHOLE STORMFILTER - PLAN VIEW �1� 1 30'6 PRME AND COVER (5TD) CONCRETE (5EE NOTE A) GRADE RING 51 EP (TYP) INLET PIPE -'.DPE OUTLET (SEE NOTES 5 E G) R15ER WM SCUM DAM E r� 4' G" MIN (5EE NOTE 7) 5ALLA51 (5EE NOTE 5) YIEIGII7 dO `\\ WIDTH I �-�— `— SEE DETAIL 2/2 UNDFRCRA.IN 51ORMPILTE1? CARTRIDGE MANIFOLD (iYP) (5EE NOTE 2) MANHOLE STORMFILTER - SECTION VIEW %AA� 1 TME. STo MWAR:R MANAGEWNT 0.5. PATENT Na. 5.322,629, No. 5.707.v22'no. G.027.639 OTHER 6..A 5,-a4IG4. IJAND O!M[R U5140 ECSEIGN OMWING A��ITCA�� PRECAST 72" MANHOLE STORMFILTER =�` ' PLAN AND SECTION VIEWS 1 STORMWATER STANDARD DETAIL SOLUTIONSK ll2 W012Chatorm 6t21.00111 DAl E:09126/05 SCALE:NCNE FILE NAME: MHSF7-72PC-DTL I UINWN.MJW CHECNEC:ARG l7� GENERAL NOTES i ) 51ORMPICTFP BY CONTFCH STORMWATER S0LUU01,15; PORTLAND, OR (800) SA8 4GG'7; SCAR130POUGH, ME (577) 907 867(,'; FIARIDGE, MD (8GG) 7403318. 2) PILTFP OAK ROGE(5) TO BF 51FtiON-ACTUATED AIJD SELF -CI EA.NING- STANDARD DETAIL SHOWS MAXIMUM NUMBEP Of- CARTRIDGE5. ACTUAL NUMPER REQUIREC TO BE 5FECINED ON 51iE PLANS OR IN DATA TABLE BELOW. 3) PRECAST MANHOLF 5TRUCTURF TO BE CONSTRUCTED IN ACCORDANCE WITH ASTM C478. DETAIL PtfLFL;L`> DE:iIGN INTENT ONLY. ACTUAL DIMEN`ION5 AND CONF-IGUP.ANON Of STRUCTURE WILL E2 S IE)WN ON PRODUCTION OTOP DRAWING, 4) 51PUCIURE AND ACCE55 COVEP5 TO MEET AA51"1011-20 LOAD PATING. 5) STORMfIL-ER PFOUIPES 2.3 FEET OF DROP PROI0 INLET TO QUTLCT. IF 1.1155 DROP 15 AVAIIA.51-E, CONTACT CONTECI'I ,5 ORMWATER 501UTION5. MINIMUM ANGLE BETWEEN INI ET AND OUTLET 15 45°. G) INLET PIPING TO BF 5FECIFIED BY ENGINEER AND PROVIDED BY CONTRACTOR. PREC/t5T MANHOLT SIORMFII.TER FOIIIPFED WITH A DUAL DIAMETFP HDFE OUTLET STUB AND 5AND COLLAR, EIGHT INCH. DIANIE ILK OUTLET 5PCIION MAY BE 5FFARATFD FROM OUTLET 5TU13 AT MOLI)f1) IN CUT LINE TO ACCOMMODATE A 12 INCH OUTLCT PIPE, CONNECTION TO DOWNSTREAM PIPING TO BE MADE U51NJ A FLEXIBLE COUPLING OR ECCFNTRIC RFDUCFR, A5 REQUIRED. COUPI ING 5Y FERNCO OR EOUAL AND PROVIDED 13Y CONTRACTOR. 7) PROVIDE MINIMUM CIFARANCE FOR MAINTENANCE ACCE55, IF A 5HAI.I.Oh/ER SY5TEM 15 REQUIRED, CONTAQ COM[CH 51OF.MWA1 ER 5OLUTION5 FOR OTHEP OPTION5, 8) ANTI-PIOTATION RAI 1-45T TO GE 5PFGIfI[D BY FIJGINEFP AND PROVIDED BY CONTRACTOR, IF REQUIRED, PALIAST TO BF SET AROUND THE PFRIMETER OF THE STRUCTURE. 9) ALJ. 51ORMFII.TFR5 RFOURE REGULAR MAINTENANCE, REFER TO OPERA ON AND MAINTENANCE GUIDFI INE5 FOR tvORE INFORMATION. 30'0 fDAME AND COVER (STD) MANHOLE STORMFILTER- TOPVIEW rl \2� OUTLET 5AND'01IAR R15FP I P`0 OUTLET 5TUB a MOLOFD-IN CUT LINE NC 8"0 OUTLET 5TU13 OUTLET FIFE (DY CONTRACTOR) COUPLING (13Y CONTRACTOR) (5EE NOTE G 13AI.IAST GROUT (5EE NOTE 8) (BY CONTRACTOR) MANHOLE STORMFILTER - OUTLET DETAIL %2) 2IDIlBS't63MGSnf2)r11STormwater Solutions 2 IhE STORWIATCR MAW,[ W111 U 5. PATI NT No. 5,322.G29. No. 5.707,527, No. 6,027.639 8n. GA4RO-3. No.'i,G2a,57G. AND OrhER U.5. AND FCU..IGN FAINTS PENDING A�UcLIVE^PRECAST 72" MANHOLE STORMFILTER J" vwval — ° NOW H TOP AND SECTION VIEWS, NOTES AND DATA 2 STORMWATE/R^_ STANDARD DETAIL Ste/ oLUT�o Ns� 212 oontechmormwetecwm DATE:09126105 I SCALE: NONE FILE NAME: MHSP7-72PC-D1L DMWN: M.NJ CHECKED:ARG Dcl 41 INLET P (5EE NOTE5 5 k MANHOLE STORMFILTER - PLAN VIEW%1� 1 30"0 FRAME AND COVER(5TD) CONCRETE (,SFE NOTE 4) GRADE RING STEP (NP) INLET PIPE HDPE OUTLET 1 (5EE NOTES 5 6 6) P15EP WITH SCUM BAPPLE 4 6" MdN r� (SEE NOTE 7) 5TORMFII TER CARTRIDGE (TYP) (5EE I40TE 2) BAIL+ST . (SEE NOTE 8) HEIGHT a ---� -�— •WIDTH , UNDERDRAIN 5EE DETAIL 2/2 MANIFOLD MANHOLE STORMFILTER - SECTION VIEW (:A) 1 UTL.ET 55 E Fi) THL `dTOPW Wh1ER MA NAGTMENI SW -NO 5.3 U.S. PATCM No. 5,322,629, No. 5,707,527, N.. G1027 G39 No. D OTHEK U No. 5,624, IGN AND pinfR 0.5. AND FOREIGN 02006 CONTECH Stonwater Solutions rATrNTs -NDING A� Umrle^L o PRECAST 48" MANHOLE STORMFILTER DRAWING STORMWATER PLAN AND SECTION VIEWS �-SO K STANDARD DETAIL WrNeCh810"W8ler.WM DAT E: 09126105 SCALE: NONE I FILE NAME: MHSE3�48PGDTL I DRAWN: MJW I CHECKED: ARG Do GENERAL NOTES 1) STOKMf11TER BY CONTECH 5TORM`4AAT(_R 501A1TION5t FORTLAN ), OR (800) 548-4667: ,CAPbOKOUGF' ME (877) 907-8676; EI KP.IDGE. MD (866) '740 33 i 8. 2) PIF?ER CARTRIDGf(51 TO EF 51Fi ION -ACTUATED AND 5EI_P-CLEANING. SANDARD DETAIL SHOWS MAY.IMUM NUIvIl3ER OP CARTRIDGFS. ACTUAL NUMBER REQUIP.ED TO 5E SPECIFIED ON 511 F PLANS OR IN DATA TABLE BELOW. 3) PRECAST MANHOLE STP.UCIUP.E TO BE C:ONSTRUC'FD IIJ ACCORDANCE `/✓ITH ASTM C4'78. CE?All. P.EPLECTS DESIGN INTENT ONLY. ACTUAL DIMCN51011S AND CONFIGURATION Of STRUCTURE Witt BF SHOWN ON I-RODUCI'ION SFIOP CRANING. A) STRUCTURE AND ACCESS COVLPS TO MEET AA511"10 Ii -20 LOAD RATING. 5) 51ORMI'V ER REQUIRES 2.3 FEET OF DROP FROM INLET TO OUTLET. IF LF55 DROP 15 AVAIIA.511. CONTACT COMECIt j1ORMWNIER 501UTIONS. MINIMUM ANGLF F)FTWFEtl INI E? ANC QUTI'[T 15 45°. G) INLI' PIPING TO BE 5PECIFIED BY FIJGIPJEER AND PROVIDED 6Y CONTRACTOR. PRECAST MAIJt101.E STORMFIISER EQl11PPED WITH A DUAL DIAMETER IOPE ONE LET STUB AND SAND COLLAR, EIGHT INCH DIAMETER CUII D SECT ON MAY 51E SEPARATED FROM OUTLET STUB AT MOLDED -IN CUT LINE TO ACCOMMODATE A 12 INCN OUTLET PIPE. CONNECTION TO DOV✓N5?P.EAM PIPING TO BE MADE U51NG A fLEX161 E COUPIINC OR ECCENTRIC REDUCER, AS RFQUIRFD. COUP[ ING BY f'ERNCO OR EQUAL AND PROVIDED BY CONTRACTOR. 7) PROVIDE MINIMUM CLEARANCE FOR MAINTENANCE ACCP. 55. IF A SHALLOWER SYSTEM IS REQUIRED, CONI ACT CONI ECH STORMWATER SOLUTIONS FOR OTHER OPTIQIJ, 8) ANTI P -I OTA110N BAIJA57 TO BE SPFCIFIED BY FNGINFFR AND FROVIDEG BY CONTRACTOR, IF REQUIRED. DAI I AST TO BE 5[i AROUND T IIE PERIMETER Of THE STRUCI URF. 9) ALL STORMFILTERS KEQUIKE REGUTAK MAINTENANCE. REFER TO OPERATION AND MAINTENANCE GUIDELINES FOR MORE INFORMATION. 30'0 FRAME AND COVEK (STC) MANHOLE STORMFILTER - TOP VIEW 2 QUTIFT SANG COLIAR R15ER A / ( 'Jl OUT1 3TUB LD a' MOED-IN CUT LINE i— 8"O OUTIU71 FTSTUB OUT[ ET PIPE (t3Y CONTRACTOR) COUPLING (EiY CONTRACTOR) (5EE NOTE G) HALIAST GROUT (5EE NOTE 8) (EiY CONI PACIOR) MANHOLE STORMFILTER - OUTLET DETAIL (2� 2 STORMWATER SOIUTIONSK THE STOJ W WA1 CR MANA6-PJA NT 5W'I,f w U.`_i. PATENT No. 5.322,619, ago. 5,707,52V, Ito, 6,02.9,639 No. G,G49,018, No. 5,G24,576, AND OTHER U.S. AND fCREIGi\' PAMI T5 P.'.ROIN'G PRECAST 48" MANHOLE STORMFILTER TOP AND SECTION VIEWS, NOTES AND DATA STANDARD DETAIL DATE:0917.6105 SCALE:NONE TILT NAME MHSfJdBPG)ill DRAWN: MJ 2 CM APPENDIX E Conveyance Calculations Worksheet for Main S® 12" @.4% Project Description Friction Method Manning Formula Solve For Normal Depth Input Data> - Roughness Coefficient 0.015 Channel Slope 0.00400 ft/ft Diameter 1.00 ft Discharge 1.55 ft3/s Results Normal Depth 0.67 If Flow Area 0.56 ftp Wetted Perimeter 1.92 it Top Width 0.94 ft e'4 Critical Depth 0.53 ft Percent Full 67.3 f Critical Slope 0.00839 fUft INS 2 D Velocity 2.76 ft/s f---- 2 , i Gx i Velocity Head 0.12 ft hi,n, G�r�_r,h� Veto<-�� !S MCA, Specific Energy 0.79 ft Froude Number 0.63 Maximum Discharge 2.10 l Discharge Full 1.95 ft'/s Slope Full 0.00252 ft/ft Flow Type SubCritical GVF Input Data Downstream Depth 0.00 it Length 0.00 It Number Of Steps 0 GVF Output Data Upstream Depth 0.00 ft Profile Description Profile Headloss 0.00 it Average End Depth Over Rise 0.00 Normal Depth Over Rise 67.25 % Downstream Velocity Infinity ft/s Upstream Velocity Infinity fps Bentley Systems, Inc. Haestad Methods Solution Center Bentley FlowMaster [06.01.071.00] 1111112009 4:41:40 PM 27 Siemens Company Drive Suite 200 W Watertown, CT 06796 USA +1-203455-1666 Page 1 of 2 Worksheet for Main SD 12" @.4% GVF Output Data Normal Depth Critical Depth Channel Slope Critical Slope 0.67 ft 0.53 ft 0.00400 ft/ft 0.00839 Wilt Bentley Systems, Inc. Haestad Methods Solution Center Bentley FlowMaster [08.01.071.00] 11/1112009 4:41:40 PM 27 Slemons Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 Page 2 of 2 Worksheet for Roof Lines Project Description Friction Method Manning Formula Solve For Discharge Input Data Roughness Coefficient 0.015 Channel Slope 0.01000 ft/ft Normal Depth 0.50 ft Diameter 0.50 ft Results Discharge 0.49 ft'/s Flow Area 0.20 fi Wetted Perimeter 1.57 ft Top Width 0.00 ft Critical Depth 0.36 ft Percent Full 100.0 % Critical Slope 0.01369 ft/ft �-{ SV m1n {1115 2.,0 �5 Velocity 2.48 f/s <— �`t$ Velocity Head 0.10 ft G�Pa-✓`h� vt to�bl� �S �^'��'� Specific Energy 0.60 ft Froude Number 0.00 Maximum Discharge 0.52 W/s Discharge Full 0.49 W/s Slope Full 0.01000 ft/ft Flow Type SuIrCritical GVF Input Data Downstream Depth 0.00 H Length 0.00 ft Number Of Steps 0 GVF Output Data Upstream Depth 0.00 ft Profile Description Profile Headloss 0,00 ft Average End Depth Over Rise 0.00 % Normal Depth Over Rise 100.00 % Downstream Velocity Infinity ft/s Upstream Velocity Infinity ft/s Bentley Systems, Inc. Haestad Methods Solution Center Bentley FlowMaster [08.01.071.001 11/11/2009 4:41:57 PM 27 Siemens Company Drive Suite 200 W Watertown, CT 06795 USA +1.203.7551666 Page 1 of 2 Worksheet for hoof tines GVF Output Data Normal Depth 0.60 ft Critical Depth 0.36 ft Channel Slope 0.01000 ft/ft Critical Slope 0.01369 ft/ft Bentley Systems, Inc. Haestad Methods Solution Center Bentley FlowMaster [08.01.071.00) 11/11/2009 4:41:57 PM 27 Siemens Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 Page 2 of 2