Loading...
The URL can be used to link to this page
Your browser does not support the video tag.
Home
My WebLink
About
SWP272200
Short Plat (Sf IPL If ) REQUEST FOR PROJECT u Prclim. Plat (PP/1' ) -CAGa To: Technical Services Date S—Z - 9s' w0u 87(0 9 0 Grccnll From: Plan Rcvicw/Projcct Manager pAL/L L y rK 8A/Z 7- Project Name Al. W, 1-14ty49L//YG- S11—TN' M S OACIC4 ZwA�C�h/yVS.0 (20 charactcn max) Description of Project: COA_o iCVCT10A, 0X (3Z ,Sp 0 ,M per OFj<«� /WA/lE�iir.t� v/G 14VG1- . D v S,o� D w/G L S L C /�i4 y/NCr_ Ae/ue w.4y, EoAAJF r4[lr w fi��D�Aiv T. S4wi�i�t y sib ;rA4A6< sTorQ�1 O0?41#v S�isn i- Circle Size of Waterline: 8" 10" (2" 4 Circle One: Nett' or Extension Circle Size of Sewerline: 10" 12" Circle One: New or Extension Circle Size of Stormline: l2" 15" 18" 24" Circle One: Ne.v or Extension i Address or Street Names) Avv�4G /9V�,.�.!�/, ,S�W� 7_2W 57 • Dvlpr/Contractor/Owner/Cnslt: ^/mow. A40' "OI.✓/V /ST.E'/4� dEf jr 16AI G,eov? Check each discipline involved in Proj*w Ltr Drwg u of sheets per discipline �( Trans-Storm J /2�1,D, ) sic•W 4&W7dN) Vol3 sh/ Ts (RoadtYdy�rdinage) (offsite inl[K—Cmals)(inetudc basin name) . (indudc TESC shccu) ❑ Transportation (SipulizatioR Clunnctiiilioq Lightinp� ❑ Wastewater (Sanitary$ewer Main)(include basin name) — �( water 78w./ry; /0"(M;ai A 0Me)VA14Ar A?rEM�e y lu,valves,Hydrants) _ ✓ Z sff,,L��.T-f (Include composite&Horizontal Girl Shccts) TS Use Only ` E� UIR 7 0- `,PProved by ITSM Date 6rnWmisd92-090.DoC/CD/bh TECHNICAL INFORMATION REPORT N.W. Handling, Powell Ave . & S .W. 7th ST . BY SITE DEVELOPMENT SERVICES 310 208TH ST SE BOTHELL 98012 481-9687 February 6, 1995 "lls,011 r , GEOTECH CONSULTANTS, INC. December 7, 1994 13256 N.E.20th St.(Northup Way),Suite 16 Bellevue,WA 98005 JN 94425A (206)747-5618 FAX 747-8561 Northwest Handling Company 838 Seneca Avenue Southwest Renton, Washington 98055 Attention: Jim Franck Subjects Executive Summary and Transmittal Letter Phase 1 Environmental Site Assessment Commercial Site 1100 Southwest 7th Street Renton, Washington Dear Mr. Franck: Enclosed is the Phase 1 Environmental Site Assessment of the commercial site located northwest of the intersection of Southwest 7th Street and Powell Avenue Southwest. This report was prepared in accordance with the terms of our proposal dated November 9, 1994. Executive Summary The subject property is currently undeveloped, and from our historical review of the property, it appears to have been free from major development throughout its history. Prior to the 1950s, a fairway and green for the Earlington golf course existed on the property. The old Black River channel appears to have passed by the site, as it ran just south of Southwest 7th Sheet. As part of our rc<.ently completed geotechnical engi.leering study, v,•e excavated six test pits on the si.►bjPc;t rr-perty. No substantial fill soils and no odors or visibly stained soils were obsarveu in our test pits. The surrounding properties are oped with commercial buildings. At the nearby Black River Corporate Park to the west, some fairly significant environmental concerns have been encountered regarding the placement of fill soils derived from dredging and excavation in the adjacent Mill Creek channel. The nearest property line of the Black River Corporate Park is located approximately 500 feet west of the subject property. Based on the measured local hydraulic gradient as presented in a report prepared for the Black River Corporate Park by another professional engineering firm, the corporate park is downgradient from the subject property. Due to the above information and the absence of fill soils from this source on the subject site, it is our opinion that the environmental issues impacting the Black River Corporate Park do not appear to have environmentally impaired t the subject property. ION w=�=. t ;,e;SaN Northwest Handling Company JN 94425A December 7, 1994 Cover Letter/Page 2 This assessment revealed no evidence of recognized environmental conditions in connection with the property. A discussion of the scope of our work, our site observations, and our conclusions are contained in the attached report. We appreciate the opportunity to be of service on this project. If you have any questions, or if we may be of further service, please do not hesitate to contact us. Respectfully Submitted, GEOTECH CONSULTANTS, INC. James H. Strange, Jr. Environmental Engineer GEOTECII CONSULTANTS,INC. PHASE 1 ENVIRONMENTAL SITE ASSESSMENT Commercial Site 1100 Southwest 7th Street Renton, Washington TABLE OF CONTENTS INTRODUCTION........................................................................................................................ 1 Purpose................................................................................................................................ 1 Limitations............................................................................................................................ 2 Methodology and Scope of Work........................................................................................ 2 SITEDESCRIPTION...................................................................................................................3 Location................................................................................................................................3 SiteGeology.........................................................................................................................3 Site and Vicinity Characteristics...........................................................................................3 Current Uses of Site and Adjoining Properties.................................................................... 4 Past Uses of Site and Adjoining Properties......................................................................... 5 RECORDSREVIEW...................................................................................................................7 County Abandoned Landfill Records................................................................................... 7 WDOE Underground Storage Tanks....................................................................................7 WDOE Hazardous Site Listings............................................................................................8 EPAHazardous Site Listings.............................................................................................. 11 CERCLIS.................................................................................................................... .11 ERNS............................... ............................. ....................................................... ....11 FINDS.......................................................................................: ............................. .. 11 Reviewof Previous Site Reports........................................................................................ 12 SITERECONNAISSANCE........................................................................................................13 Radon................................................................................................................................. 13 CONCLUSIONS.......................................................................................................................13 REFERENCES..........................................................................................................................15 ATTACHMENT Plate 1 Vicinity Map GEOTECII CONSULTANTS.INC_ PHASE 1 ENVIRONMENTAL SITE ASSESSMENT Commercial Site 1100 Southwest 7th Street Renton, Washington LNTRODUCTION This report presents the results of our Phase 1 Environmental Site Assessment of the commercial site in the Earlington area of Renton. The site covers approximately 3 acres northwest of the intersection of Southwest 7th Street and Powell Avenue Southwest. Purpoe The purpose of an environmental assessment is to satisfy one of the requirements to qualify for the innocent landowner defense in the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA): that is, to make "all appropriate inquiry into the previous ownership and uses of the property consistent with good commercial or customary practice." Our scope of work and the limitations of our study are consistent with the recently released American Society of Testing and Materials (ASTM) Designation E 1527-93, "Standard Prac- tice for Environmental Site Assessments: Phase 1 Environmental Assessment Process." The objective of a Phase 1 assessment is to minimize potential future liability for environ- mental problems by demonstrating that at the time this report was prepared, the owner, Bolder, or buyer had no knowledc;e Cr reason to kno,, that any hazardous substance hay: beer: rc!eased or disposed of on, in, or -%,the property. ;,.: �ur.:irlo�gal objective of the Phase 1 assessment is to identify potential contamination souNoes. The goal of the processes established by ASTM is to identify recognized environmental conditions. The term "recognized environmental conditions" means the presence, or likely presence, of any hazardous substances or petroleum products on a property under conditions that indicate an existing release, a past release, or the material threat of a release of any hazardous substances or petroleum products into structures on the property or into the ground, groundwater, or surface water of the property. The term includes hazardous substances or petroleum products even under conditions in compliance with laws. The term is not intended to include de rninimis conditions that generally do not present a material risk of harm to public health or the environment and that generally would not be the subject of an enforcement action if brought to the attention of the appropriate governmental agencies. GEO'IBCH CONSULTAN-IS,INC. Northwest Handling Company JN 94425A December 7, 1994 Page 2 Limitations This report has been prepared for the exclusive use of the Northwest Handling Company, Seafirst Bank, and their representatives for specific application to this site. This work was performed in a manner consistent with that level of care and skill normally exercised by members of the environmental science profession currently practicing under similar conditions in the area, and in accordance with the terms of our proposal dated November 9, 1994. If new information is developed in future site work, which may include additional excava- tions, borings, or studies, Geotech Consultants, Inc. should be given the opportunity to review the findings, re-evaluate the conclusions of this report, and provide amendments as required. Methodology and Scope of Work Our study included: O A review of the chronology of ownership and site history, using county assessor records, title company documents, interviews with individuals familiar with the subject property, and aerial photography as primary resources. An attempt was made to identify possible former industries or uses presenting some probability of generating waste, which may have included dangerous or hazardous substances, as defined by state and federal laws and regulations. O A reconnaissance of the property 20 look for evidence of potential contamination, in the form of soil stains, odors, vegetation stress, discarded drums, or discolored water. O Acquisition and review of available reports and other documentation pertaining to the subject site or nearby sites. O A review of King County Health Department documents pertaining to current and abandoned landfills, along with a review of the statewide municipal solid waste listings published by the Washington Department of Ecology (WDOE). O A review of the WDOE's current listing of underground storage tanks (USTs), along with the current WDOE Leaking Underground Storage Tank listing, for any USTs in the vicinity of the property. O A review of the Emergency Response Notification System (ERNS) listings. G) MEC11 CONSUL;IAN S,INC. Northwest Handling Company JN 94425A December 7, 1994 Page 3 O A review of the current WDOE Confirmed and Suspected Contaminated Sites (C&SCS) report of sites that have been the subject of hazardous waste investi- gation or cleanup activity in conjunction with the Washington Model Toxics Control Act (MTCA), Chapter 173-340 WAC. O A review of the EPA's Comprehensive Environmental Response Compensation and Liability Information System (CERCLIS) list of sites that are potentially contaminated. This list includes National Priority List (NPL) sites. We also review the Facility Index System Database (FINDS) for Resource Conservation and Recovery Act (RCRA) generator sites and TSD facilities. When more detailed information is appropriate, we review the RCRA Notifiers list and the enforcement and compliance monitoring list. SITE DESCRIPTION Location The property is located in the alluvial valley between the Cedar and Green Rivers in the Earlington area of Renton, Washington. The general location of the site is illustrated on the Vicinity Map, Plate 1. The site is composed of Lots 5 and 6 of the plat of the Washington Technical Center. e Geology The site is mapped by the U. S. Geological Survey as alluvium, or a mix of sand, silt, and clay deposited by the White and Green Rivers before the diversion of the White River to the south in 1906. Our recently completed test pits on the site generally confirm this designation. Site and Vicinity Characteristics An environmental assessor from our firm visited the site on November 17, 1994 to observe on-site conditions and land use practices in the surrounding area. Land use in the vicinity is characterized by commercial development. Generally, the land to the south of the site has been fully developed for corporate uses, while areas to the north of the site are scarcely developed. More specifically, the property is bordered as follows: GE01T,CII CONSULTANTS,INC. Northwest Handling Company JN 94425A December 7, 1994 Page 4 North: The three-story Rivertech office building is somewhat north of the property. East: A single-story office building occupies the lot nearest to Southwest 7th Street. The remainder of the adjacent lots across Powell Avenue Southwest are cleared but undeveloped. South: Southwest 7th Street separates the site from a large corporate business park. A large warehouse building that houses the E. J. Ba tells Company is located to the southeast of the subject property. West: The Lowes business park, which consists of several one-story offices, is adjacent to the site. The topography of the site and surrounding area is generally flat to slightly undulating. Based upon local drainage patterns, groundwater gradients measured by other firms, and our review of U.S. Geological Survey maps of the area, it is likely that the flow of surface water, or shallow-seated subsurface water, across the property would be from the east toward the west. Current Uses of Site and Adjoining Pro erties The undeveloped subject property covers approximately 3.09 acres in the Earlington area of Renton. The site consists of two neighboring lots on the northwestern corner of the inter- section of Powell Avenue Southwest and Southwe5, %t� Street- The southern lot is rectangular with appror,rlaiHly 310 feet of frontage along �-Ic uthwest 7th St',:,' to 13 .south and approximately i 61 feet of frontage along Poweli Avenue Southwest Lo its east. The northern lot is pie-shaped and adds approximately 309 feet of frontage along Powell Avenue Southwest. Concrete sidewalks and gutters have been constructed around the subject site. The site grade gently undulates, and it is approximately 3 to 4 feet below the level of Powell Avenue Southwest. A majority of the brush that undoubtedly covered the site has been cleared by a mulching machine. Medium to small deciduous trees line the western and eastern edges of the site, and the southern boundary of the property is mostly overgrown with small trees and blackberry bushes. In addition, a line of trees runs east-west across the center of the property, and a grove of medium-sized deciduous trees is located in the northeastern corner of the site. During our visit to the site, we observed some small piles of yard waste and topsoil fill that were located in the northeastern corner of the site. Since a backhoe was on the site for the geotechnical investigation, portions of the soils in the fill piles were exposed for viewing. The piles generally contained topsoil soils and some asphalt debris. No olfactory or visual GEO'IECI I C0NSUl:I'AN'IS,INC Northwest Handling Company JN 94425A December 7, 1994 Page 5 indications of petroleum-hydrocarbon contamination were observed in the exposed fill soils. In addition, we observed a 4-foot stack of wooden shipping pallets on the western end of the site. The potable water, and storm and sanitary sewer services for the site are provided by the local municipalities. The developed properties surrounding the site accommodate relatively new corporate buildings. The Lowes property to the north and the west is developed with a complex of four one-story offices that were constructed in the late 1980s or early 1990s. The large business park to the south was developed throughout the 1980s. The closest building on the southern adjacent property houses the Washington Department of Social Services. The E. J. Bartells warehouse was constructed in the early 1970s and covers most of the block to the southeast of the site. A single-story office building that was constructed in 1983 occupies the only developed adjacent lot to the east of the subject property. The remaining eastern adjacent properties have been cleared, but they are otherwise undeveloped. At the time of our visit, no major stains, odors, or unusual vegetative conditions that might indicate the potential presence of hazardous contamination were observed on the site. Past Uses of Site and Ad'ol ining Pfopertie_s Sources reviewed for information on site and area development and land use included resources at the King County Assessor's Office, the Puget Sound hranch of the Washington State Archives, and the Seai.;� Prr^l - Library, historic aerial photography; and with people familiar with the property. From a review of aerial photographs, dated 1936, 1946, 1960, 1968, 1974, 1980, 1985, and 1992, it appears that other than being in use as part of the Earlington golf course prior to the 1960s, the subject property has remained undeveloped. Specific observations and inter- pretations made during our review of historic aerial photographs of the site and surrounding region are summarized below: 1936: The site is developed with a portion of a green and fairway for the Earling- ton golf course. The line of trees that bisects the site today appears to be in place. The golf course is very large and extends west to the Black River, south to the future location of the 405 freeway, north to the Sunset Highway, and east to Rainier Avenue. The Black River channel appears to run east-west along the southern edge of the future Southwest 7th Street. Other than the golf course, the area is largely undeveloped. GEOTECII CONSULTANTS,INC Northwest Handling Company JN 94425A December 7, 1994 Page 6 1946: The portion of the golf course south of the Black River appears to have been converted to a farm. In addition, the area of the course that includes the site appears to be not in use. 1960: The use of golf course in the area of the site has been terminated. 1968: The section of the Black River channel to the south and the east of the site has been filled. A wet depression is visible to the northwest of the subject property. The area to the south of the site has been stripped, and the construction of some of the structures remotely to the east of the site has begun. 1974: The E. J. Bartells warehouse to the southeast of the site is visible. Southwest 7th Street has been extended past the site and Powell Avenue Southwest has been installed. in addition, a relatively small building has appeared on the property to the southwest of the subject property at the end of Southwest 7th Street. A dirt parking area is to the east of this structure. 1980: The site and surrounding area appear similar to the preceding photograph. 1985: Several of the northeastern structures for the corporate park to the south of the site have been constructed. The lone office to the east of the property is visible. 1992: The subject property aria surrou-i tiding area appear much us they do today. The site is partially overgrown, but some parking of vehicles on the site s evident from the bare dirt patches in the southwestern corner. The undeveloped parcels to the east of the site have not been cleared, and they are heavily overgrown. The Lowes business park to the west has been constructed, and a majority of the park to the south has been filled in. A review of records at the King County Assessor's Office indicates that the current owner is L-O Renton 11, having purchased the property in May of 1990 from Equity Management, Inc. A partial list of previous owners of the property and their dates of purchase are as follows: Pacific Coast Railroad (1954) Julius Rosso (1950) Washington Mutual Savings Bank (1940) Hale E. Ryan (????) James -Thompson Investment Co. (????) GG01110H CONSULTANTS,INC. Northwest Handling Company JN 94425A December 7, 1994 Page 7 i Information from the Washington State Archives indicates that the property has never been developed with any sort of permanent structure. i s Based on this information, it appears that the site does not have a history of industry, manufacturing, chemical distillation, waste disposal, or other uses that might have exposed it to toxic, hazardous, or dangerous substances. RECORDS REVIEW C2uray Abandoned Landfill Records A review of the King County Health Department records pertaining to current and abandoned landfills within the city suggests that the Renton Junction facility is the only landfill located within 1 mile of the property. A statewide listing of municipal solid V%,aste facilities does not record any landfills in this area. The Renton Junction abandoned landfill, located at the Burlington Northern Railroad and Monster Road, is approximately three-quarters of a mile southwest of the subject site. King County operated a sanitary landfill at the Renton Junction from approximately 1946 to 1961. The City of Renton also reportedly utilized the site as a depository for some of its solid wastes. Numerous complaints were received regarding fire, smoke, and inadequate soil cover. In addition, some problems with the dumping of sewage and oils were noted. The site was officially closed in 1957, but filling on the site continued for about another two years to bring the site to a"ucable" condition. According to the King County report coocerning the landfill, the proximity of major industries makes it possible that some potentially hazardous materials were deposited at the landfill site during the years of its operation. However, due to the distance separating the aban- doned landfill and the subject property and the downgradient location of the landfill, the probability that the materials deposited at the Renton Junction landfill would environ- mentally impact the subject site is low. WDOE Underground Storage Tanks Our review of the WDOE listing of underground storage tanks (USTs), dated November of 1994, revealed no registered USTs on, or adjacent to, the subject property. However, four UST sites within a half-mile radius of the property are on the current WDOE's Leaking Underground Storage Tank (LUST) list, dated October 28, 1994. GEOTEC11 CONSULTAN75,INC. Northwest Handling Company JN 94425A December 7, 1994 Page 8 Hydrologic Com"ar-Y and Address Media Location* WDOE Remarks Cummins Northwest Soil CG Conducted 811 SW Grady Way 2,000 feet southeast Ryerson Store Soil CG Conducted -two diesel 600 SW 10th Street tanks removed 8/93. 1,800 feet southeast 225 cy. PCS exported. US West Renton Admin Soil UG In Progress - one diesel and 300 SW 7th Street two unleaded gas tanks removed. 2,200 feet east Possible GW impact. K& N Meats Soil UG Conducted - one gas, one 601 Seneca Avenue diesel, and one waste oil 1,500 feet east tank removed. -------------------------------------------------------------------------------------------------------------------------------------------- Notes: * "Hydrological Location" refers to the position of the UST in relation to the subject property and the probable direction of shallow groundwater flow. UG and CG denote upgradient and crossgradient locations, respectively. PCS refers to petroleum-contaminated soil. GW denotes groundwater. Our ,-cview of U.S. Geologlcai Survey topograptm.; ma ,. ;ir the area suggests that vocal drainage patterns of shallow groundwater flow are, generally to the west into Mill Creek (see the attached Vicinity Map, Plate 1). Measured groundwater gradients for the immediate area of the site reported by another environmental firm confirm these patterns. Based on the distances separating the tank sites from the subject property, it is our opinion that the potential for environmental impairment of the subject property by water-borne petroleum contaminants from any of these potential sources is low. For your reference, the approximate locations of the tank sites are noted on the Vicinity Map, Plate 1. WDOE Hazardous Site Listings A review of the WDOE Confirmed & Suspected Contaminated Sites (C&SCS) report, dated November of 1994, revealed several sites within 1 mile of the property that have been desig- nated as confirmed hazardous substance sites. These are listed below: GEOTECH CONSULTANT'S,INC. Northwest Handling Company JN 94425A December 7, 1994 Page 9 Site and Status Affected Media Contaminants Washington Natural Gas DW, Soil S: 15 319 South 3rd Street 1 mile NE, upgradient awaiting assessment Renton Junction Landfill Soil, GW, SW S 1800 Monster Road 3/4 mile SW, downgradient awaiting assessment Black River Corporate Park Soil C: 3,7 Oaksdale Ave. SW @ Monster Rd. GW, Sed, SW S: 37 500 feet W, downgradient undergoing independent remedial action ----------------------------------------------------------------------------------------------------------------------- Contaminant Key: C - Confirmed GW- Groundwater S - Suspected SW- Surface Water R - Remediated DW- Drinking Water Sed- Sediment 1) base, neutral, acid organics 9) ncr` halogenated solvents haiv0=_•!hated organic compounds 10) dioxi,-�- 3) EPA priority pollutants 11) FA,Hs 4) metals 12) reactive wastes 5) polychlorinated biphenyls (PCBs) 13) corrosive wastes 6) pesticides 14) radioactive wastes 7) petroleum products 15) conventional organic 8) phenolic compounds 16) conventional inorganic The closest of the above sites, the Black River Corporate Park, lies approximately 500 feet west of the subject site. From our research at the WDOE C&SCS files, we have compiled the following summary. The Black River Corporate Park generally consists of property on the banks of Mill Creek and the adjacent P-1 storm detention pond. The property consists of Tracts A and B. Tract A is located on the western side of Mill Creek, while Tract B sits on the eastern edge of the GEOTECII CONSULTANIS,INC Northwest Handling Company JN 94425A December 7, 1994 Page 10 creek. A portion of the P-1 pond forms the northern boundary of Tract A and part of Tract B's northwestern boundary. In 1984, the City of Renton and the Soils Conservation Service began an enlargement project at the P-1 pond. The detention capabilities of the pond were expanded through the excavation of shoreline soils and the dredging of the sediments deposited behind the P-1 pump station at the western outlet of the P-1 pond. Placement of the dredged fines was mainly confined to the center of Tract A, while the excavated shoreline soils were placed throughout both Tracts A and B. The P-1 pond is located downstream from the Western Processing facility. Metals, solvents, and hydrocarbons were reportedly released into Mill Creek by the plant. In 1984, surface water samples from Mill Creek collected by the EPA showed that organic chemical concentrations (solvents and hydrocarbons) rapidly decreased to be!ow detectable levels within approximately 1,000 feet downstream of the plant. However, their investigation indicated that metals concentrations contained in the sediments had been transported at least 1 mile downstream and had, in all likelihood, affected all of the areas of Mill Creek downstream from the plant. Metals identified in the sediments by the EPA included cadmium, chromium, lead, nickel, and zinc. By 1987, remedial procedures at Western Processing were largely completed, but surface water samples from the creek collected from a location approximately 1 mile upstream from the P-1 pond indicated high metals concentrations with no signs of declination with recession from the Western Processing plant. Several firms have assessed the situation regarding the Black River Corporate Park and conducted borings to investigate the contents of the fill soil:: piar:ed on the site. The most recent report issue; ;y Hart Crowser in June of 1991 indicate that F: veral recognized hazardous materials were contained in the fill soils deposlr3d on the corporate park site. Soils containing concentrations of cadmium, chromium, nickel, zinc, and total petroleum hydrocarbons above "conservative" MTCA cleanup standards were encountered on Tract A of the Black River Corporate Park. The majority of Tract B was found to contain only native soils, but in the southeastern portion, fill soils containing concentrations of cadmium and mercury above the MTCA cleanup levels were encountered. Soils underlying the site were generally found to be relatively non-permeable silts mixed with relatively permeable sands. Groundwater was encountered from 15 to 20 feet below grade. The Hart Crowser report also showed that the measured groundwater gradient (from an earlier Shannon and Wilson study) on the eastern side of Mills Creek declines to the west. Based on the measured local hydraulic gradient as presented in the Hart Crowser report, the corporate park is downgradient from the subject property. Due to the above information and the apparent absence of substantial fill soils on the subject site, it is our opinion that the environmental issues impacting the Black River Corporate Park do not appear to have environmentally impaired the subject property. Based on the distances separating the other CEOTECII CONSULTANIS,INC. Northwest Handling Company JN 94425A December 7, 1994 Page 11 two C&SC sites from the subject property, the probability of hazardous materials deposited on the sites environmentally impairing the subject site would be considered to be low. EPA Hazardous Site Listing$ CERCLIS A review of the EPA's CERCLIS listing, dated November of 1994, revealed no active sites within approximately 1 mile of the subject site that have been designated as potentially hazardous or eligible for participation in the Superfund cleanup program. ERNS They subject property does not appear on the current ERNS listing for King County, dated February of 1994. FINDS Our review of the Facility Index System (FINDS) listing and the EPA's RCRA Notifiers list revealed three businesses adjacent to the subject property that are regularly monitored by the EPA and the WDOE for their use or generation of small amounts of hazardous substances as a normal part of their business activities. Reg"I or E. J. Bartells HWDMS t, 700 Powell Avenue Southwest George A. Hormel and Company HWDMS, TRIS 1, G 600 Southwest 7th Street Grinnell Fire Protection Systems HWDMS, TRIS 1, G 875 Southwest 7th Street ------------------------------------------------------------------------------------------------------------------------- Regulatory Agencies: HWDMS Office of Solid Waste (RCRA listing). TRIS Office of Toxic Release Inventory. GEMECIi CONSULTAKIS,INC Northwest Handling Company JN 94425A December 7, 1994 Page 12 Generator Codes: 1) Large Quantity Generator, more than 1000 kilograms per month of hazardous material. 2) Small Quantity Generator, between 100 and 1000 kilograms per month. 3) Conditionally Exempt Small Quantity Generator, less than 100 kilograms per month. Non-Regulated Codes: G - Non-Regulated Hazardous Waste Generator. None of the listed FINDS sites within a half-mile radius have a history of violations or enforcement actions according to the HWDMS compliance list dated January 20, 1994. No treatment, storage, and disposal (TSD) facilities are located within 1 mile of the property. Businesses named in the FINDS listing are users or generators of potentially hazardous or toxic materials as a normal aspect of their business practices. The !;sting also includcic treatment, storage, and disposal (TSD) facilities. Listed businesses are requ.;,—d tc c.-W-,r!y monitor and report ilie:.- use or generati.--n -f materials to the EPA,. Based on the monitoring and reporting requirements imposed by the EPA, on our review of the EPA Hazardous Waste Data Management System (HWDMS) compliance listing, and on the assumption that the listed users and generators exercise prudence in their management of these materials to minimize liability and EPA penalties, it is our opinion that the potential for environmental impairment of the property from the listed businesses is very low. Review of Previous Site Rem We recently completed a geotechnical engineering study for the subject property, during which we excavated six test pits. The test pits generally encountered a mixture of alluvial silts, sands, and clays that is typical for sites located in alluvial valleys. Slight groundwater seepage was encountered at 8 to 12 feet below the existing grades. No substantial fill soils and no odors or visibly stained soils were observed in our test pits. GEOIT30-1 CONSULTANTS,INC. Northwest Handling Company JN 94425A December 7, 1994 Page 13 SITE RECON_N_AISSANCE Radon Radon is a naturally occurring, highly mobile, chemically inert, radioactive gas created through the radioactive decay of uranium and thorium. The potential for the occurrence of radon varies widely and depends on: (1) the concentration of radioactive materials in the underlying bedrock, (2) the relative permeability of soils with respect to gases, and (3) the amount of fracturing or faulting in the surficial materials (EPA, 1987). The EPA has established a concentration for radon of 4 pico-Curies per liter (pC/1) of air as a maximum permissible concentration "action level." According to some studies, the average concentration in homes across the United States is on the order of 1.4 pC/I. Typically, the Puget Sound area of Washington is underlain by a consolidated thickness of glacial drift and rocks that do not contain radon-forming minerals. The Washington Department of Health, Division of Radiation Protection, published a study listing the King County average as 0.7 pC/l and the statewide average as 1.0 pC/l. Based on this information, it is our opinion that the potential for elevated levels of radon at this site is low. CONCLUSIONS We performed a Phase 1 Environmental Site Assessment consistent with the scope and limitation: of A3TM Practice F 1527-93 for the commercial site ivcated at 1100 SclAhwest 7th Street. This assessment revar�a J nc, evidence of recognized environmental in connection with the property. GE07ECII CONSULTANTS,INC. Northwest Handling Company JN 94425A December 7, 1994 Page 14 We appreciate the opportunity to be of service on this project. If you have any questions, or if we may be of further service, please do not hesitate to contact us. Respectfully Submitted, GEOTECH CONSULTANTS, INC. James H. Strange, Jr. Environmental Engineer 'P0 U sS�0r11 A1.F-� Z/7/9Y James R. Finley, Jr., F.L. pr'Incipal JHS/JRF:jcv OEO'ITCII CONSULTANTS,INC Northwest Handling Company JN 94425A December 7, 1994 Page 15 REFERENCES Division of Radiation Protection, Department of Health, State of Washington, Radiation Fact Sheet. Geotech Consultants, Inc. Geotechnical Engineering Study - same site . November 1994. Hart Crowser. J -3276 report (for the Black River Corporate Park). June 221, 1991. King County Health Department. Abandoned Landfill Toxicity/Hazard Assessment Project, 1986. U.S. EPA Region 10 lists include: Superfund Program, CERCLIS. November 1994. Facility Index System Data Base. November 1994. Facility Index System Data Base of Notifiers. November 1994. Facility Index System Data Base of Violations and Enforcement Actions. January 1994. Walker and Associates. Historic aerial photography. Tukwila, Washington. November 28, 1994. Washington Department of Ecology lists include: Leaking Underground Storage Tank listing. October 1994. Toxic Cleanup Program Site Information System of Confirmed and Suspected . Contaminated Sites. November 1994. Underground Storage Tank listing. November 1994. GEOTECH CONSULTAMIN,INC. `OUNtr IN ST �' s �r�'r'o�-1GSh\� 4s, 1` i'� + t''\ •� s ♦J f� I I ' rpUr,TN4 ST'i+ _.lE0 �f �\�• � 1' • oT' o t 7 ,r I ! , •}-�T a o 5 IlA rwg $T < >' ST I I a��.^. tlfq � .. rl• r U'r !11lTMN ST $ 11 ° •' t r•_�7 �r U! s`' �s lNr it ♦S jY' Ilr'"'l;l�,� ' S Ilfr� rl �." N In n» 7 utIKN 1 T ! O .J•���.. ���. w�< 9R✓I(.Ir«• _ `�.6 ! �Il,.n $ Ilt•«$$i a Khtdr \\ II, `. $ s,rr. �n s n•.T f�w�!C! ( tr : gyp...rl .c•'•'. .. A. ..+y4' - - .< $T I _— V• ♦ o•rr' a r r. .3f 170T•!f.a T. + 1 iN� r.ns '•' t ILcc Ij2•p N N $r '. 'TC. ��� '.r w� o 1 ,I � .r /> v.w. a •r � '-17Mu fro �. j . j j j ti �aC r°• A a.:ry T �,� •\ v.aM1 S S 'N, m tr?-- $ 12!•05, D Is ro,r•.t... 'Ir • • \ 'g •., .'o �1Y 1�...:r.+'.1 25 onl ! ;S 1 • ••°'S 12.r $r ♦ .,T^ .�f _.lrl 'I,•.� wi .- _ ■ < '12a,« $T T :, p \ \ .Ir•-a. , ; a t rl c •i rt * e on Is •�r0. ♦ a s' �sW( ti .I_ t' S J- 4 !7 I ••,T 1 aZ i ,,,III r .... rs a t",nr"v .p 1 • < :ul \� r��. 'tiy rw.t'`..' !I,'? .1\•'�; � •♦ �'n4fgp ,• rr a � !, s' I y I•' 4sr 1_ 1t;., 1 l.V•.t,lw pp s+�-✓ � at 9'!• �'�s.1''� �s_ rT1h .r,r)h '` ,.r. r a1ftPOMY w e sT :tT'_. r �.1 '� ✓ 'rOlrrt J RIy�. _';r`= er # t 1i �1a »1 : - \i\ i 1 :.,,\.s '\�\ ,r' I ',r .l��" u0 •re,♦. <TH N r b •'! `! `' \ RIVE EA IV T•c(TpS �\ ,•. r �' s s• T It • ,M t.!I ` Z , 'It IDlMI f t, Y I��T% !11lM I0,1 VILL hGE A 1'" • T IAAK * 1 ICI\ 1 2 IS01n$T tI >" I 2 ILI 25 -4 . C i l urn 1 >E' $T 1 Ch i s onya� es of grrsrA, i, •f J • {1 is I kit 1111 u 't / y,!! �! MVTN ..awGt /` ►vWY .�� < }r y� rOC.il I ,rtG�ylImW � 1 4� � is �' l! •E--V'Y' t'-! r 1 Ispp RENT N c .• t..all.s, y ♦0 tom.�, �t -- rn Amoy• Txy !� F >!• ^• >. .. 1 I ' �i� x �' � .,.,«�, I: , ITT f 'Tcr 26 CnMf1- ITQq, i L �.. I 'II I ---E' I M I 1 Ilr �I ,,.hl!I I LEGEND: ® Approximate Location of WDOE Listed Leaking UST Site Approximate Location of WDOE Listed UST Site I%kProbable Direction of Shallow Groundwater Flow Near Site VICINITY MAP GEOTECH 1100 SW 7th STREET $ c'c)NtiuLTAN•1:tir INI'. R E N T O N, WA \ Job No: Date: Plate: 94425A DEC 1994 1 • TABLE OF CONTENTS SECTION NO. Project Overview I Preliminary Conditions Summary II (Not used) Off-Site Analysis III Retention/detention Design IV(Not req'd) • Conveyance Systems Analysis and Design V (Swale Design) Special Reports and Studies VI (Not used) Basin and Community Planning Areas VII (Not used) Other Permits VIII (Not used) Erosion/Sedimentation Control Design IX Bond Quantities and Other Forms X Maintenance and Operations Manual XI (not used) • • SECTION I • PROJECT OVERVIEW • PROJECT OVERVIEW This section summarizes all of the Core Requirements . Any applicable Special Requirements will also be discussed. The project consists of 3 . 11 acres and has no structures on it . The project will result in the creation of one building to be used as a warehouse and office. The parcel is forested, with light underbrush. Because the site is part of the Plat of Washington Technical Center, detention is not required. However, because over one acre will be subject to vehicular traffic and the site is within one mile of a Class 1 or 2 stream, a water quality swale is required. This has been provided in series with biofiltration. • • MAP r.\ fi .. •i':?C r. .rd.r•-od" aS: ;:y.;'4,Sr rF �;r, `,`•6j-!. :D _T. T. ULV b.Ef• `:r• �TI 1 L=.�- - -_IC •U S I I24TI ST 1... ..._ yy r s -rzfrx 'r" J S 125TN ST Z � ?, �- VI fT +• ` � j SouiN '4Cf. ST �N ♦ N . �/ I f : < t rtH , a ,.. BURNETl ■ C���, � �J• s sf-- '^ i ti q` � S� 126t fs•n �Poh �� I?4!x s7- ? F 3 J• ,r tttl St �P / : Iz iz6nr n ? �$ IAKx���� < < p0. ,•f I7/11I /•/ I„�\ < M $ Ig L,s ,j •f• ! •11 VI St'YlNOSLX ppr, S m 17AT11 ST $`f 12ATH -ST s C N 4T11 I (� •r 1 x1.(, M/�5, �I /c)`�`N' I •.1/// .: UMN) v. t i 11M '�L' ~ !N.IIL_r• S 1'•� -i � x 1111 SI � S 12YIII T S )L a S 1J9-LI'._ s "' '\� �+ s'<I]o,x_?• s) w < T r +0 = RD < S7 m •1 $ IANGSTON RD n 0 •.. _— ..- - _ _ _ ___ r-_- _ _ _.___-___s.+ ___—_- -0K_ _� _ _ __-._♦Q, . _ C• •r• =7 1!_71zr n J' __� ' � a 1 $ AIRPORT ',i to t a Qi! yl S"�;1 JrF .-..137•YD ALI HSp 8r{?2 sr NE slS 133R0� \1'�u 51 ,-6i'ST--a _ U7xu SI_ I'^ S TILLIC ST rlil\\, A b \ NW 2N0 ST 1 S TDBIN sr Sl 1 H Y II/ r+�W rKArr r \ _ \f kI s t S 1 F.' Y{tnMIA ltt S ? ,d n N71fIRA f.141 �,; RENION In a. .. Mr ,`/ , 011 v[I ,x .fix. - i ♦•,st FOSTER `, /4, !d a L'°r�„) 1!S vl lr~. cr ; cIHrIIRr _ �G RIYfR (\` qp ry \ U�j fi r'•`f ~1, �C��j� GOLF .. ' /. / �� �,' lI !y!` sr�SL '1 LINKS )I../.S+l,rll:ullll r ! ur ruu Cd lZ gE7St.l� y+ „) i wP vl i : ••,z4 JOSS ~119IH S/ �°qti \\' S 7 1 ' `.�--_-- .(J�• SY �d•PO : y �—A7 -- S 3RD - •11 S--` ` 5 •. _RENTON < < f PK s klVl ram. \ !l.ISI ✓f`•� '1 I I iH,Y UNS I CENTER a r 1 S �il '1 J K •1,,.� (!+ Y ` 1/ I+ a r v Lltl l,. RR "x 11'Uj y, 6TH Pam'' J:�`'i• ��(�' RD •i. I05TER v, 17 r JR H5 f u J�� 143, S�� s /��a r NS 144TH N --' r I IS T S 144 { >< S a� t RD PL\ �S 143 S[T�- .f` ` Q j i < S 67H ST .-a--+-< R "--•- _ > 144T, ) A•1\ GTO N I SW 7TH '�� 5 N $T $T = x 5 s 5T - ST i �'• R Rrar 0 E v1 5 14 T t LIB > r ---- ------�----....< _,.-�... G(LA ---- •- S-9TN ST-• MlLtli••' !S s. y pENt'1 J SW S ARArOto •..4y 01� < 5 149TH 5 b.i PK, 1 5T �pY `'� i i"'rK:• cfD nA 1 t,97M > E N TO N L 1DTH G S RE ON VILLAGE S 11 ST S ,R R O I`'/ ST I S 150TH ST ,x st I i •^ f si +\ Y� t St �`'`\ •�F e x�� R I- z r sr s I• ,� ...,. 9L TH k�(DYKF 62N0 5T Y- _ ,s < , sss �� a~A a .•1j•, < J h1'1,1•rl\V- 5 G $ 8 y� /) \ ♦ ua s s a iSTx < C� 4 4 r CC '.� y s S I Sy A-16TN ST }� S F� x d GST `^TIaCMIu 16TN ST k_ sS 6TH sr 5,�,•'s SE 9 Mr OR SE'•• S� lcR''! < II Sp �... IFS 17TH N N J i q 5 1 �' P �. s' '^-- - -� << + '^S IRTH uM FR _. ST RCH POD Y LIA'KACR[S 1 Y' w 19TH S T .,'MIT• N N 'h� s �,` p�� `7 s)t: - .r rL I 7- + CRYSTA! 4/ T t/s fY 1 LLMG4LRC5 �. �M NllL1 S r,° '+��` s M • /s��,. �> SPRIT i'f� UK 1(q PKWY, s I5Bn1 ST TRALK TRACE SW 21ST ST . IPAR!(r} I PUGET ....L..---.......ST$ .I(A)1_..S������Prrrrrr� Cl r I ... la:/l H TRACK a; H1 Irrr.tIAU:I7i231 1 i �,�Cn� R.yxN 1 , •. .y 11 � 7 Sl .l;•' I sLrnlr:(N1EN > ,) a ' 7 •n 'a r W)l.• rL ` CRCSTYILY II BAKE BLV•Q•-•-•. . r°as 1 ' 'VICTOR, C• ' 'F'� f';• I\h',4. `,y+ PARK ;Il(TL SJ �� 1 d 111 YlCIgLlA JR yy a - 111 I�Sn k t' 1 V f a w i IlNrnrwY 1._ I ' 0 �:�AAK�{ y S NS �..�..�LINII:(. )i- j.. l T _ Y Po a nn• �� i lil W = ' < SE loran St^ w 1 STFANDER BLVD CN ISTE fX\' .3,z rod)' { SE 164TH ST surx ya9 GR LABEL R NTO N Sw 27TH ST s+'+ !x'n > 'S 21TIi ST N SE 164TH SI y ST r 1 p TRECK~ INo '< S 167TH $T 1•n DR 0JA ,p a V 66I11 .79111 SI st i• s)4 1 1 3 ]68TH 5T L N CT I 0 C' 29TH ST '' yz+•a �' ,,,S1 St 16),x s, r> H HC1I -1Ts R S. N s 16B ` , i;. Z S SW 307H T SE mi a IS , \ '^ SW 31ST 5T ]IST ST 46 &E 7L i p ' 1 I SW R w 37 ST 34TH `•� rx rt tr litr" a SE .^.S SEJLSIIJ.. .'. CDdWORAT ' qi sal" a Sw 172N0 ' ' /�. i ST > W S �� 6rlx r g SE I70T11 ST uOIH _ ST In '^ DR N \ _ _ h rL F - a r.IS St �:t4.. ..flI !F S'^ 172ND Pl I CORPORATE ' ., 3 ST S I72ND Si mil. SE 177,N0••'<<; S o ST___ r o OR HI LER 'BLVD <. ' > o <j �Lf�3 SE i7zao 5Y• f ______UPLAND OR la �1' - 175TH I ST ' CF+AINf TY g CL S 'fin 91 tH'ST -' •C ir" 5 114111 SI '�yr• 1/xxl;1 r ! / - } 'f HEALTH ,°C.+ ' In sT -- r z ~^I S y'., it F5 >C 176TH T i ERGEAtt •o NIOIAND D ' W SW 39TH ST / Y S .� ?$. I SE 175T d. AV of 1 CENTER /� s s SE 176TH `si J 5 ,TTW $T 'LAKE, RI L LA A 8 rlH sr _ r ST LIB PK 178TH SA H 'DR SW I1ST ST VALLEY TRI LAND DR -' 1rerH r` •• 179TH S7 H HILALs s,nx p Pp$• a - r< _ ^ • a S `,� N ,�` � fT _ ___•_.__ CE uTE o f R ss G L4 6 ♦ S 7 T .. it _ _.._._._. _ -. c • CORE REQUIREMENTS REQUIREMENT #1 : DISCHARGE AT NATURAL LOCATION Discharge from the site is to a storm drain line in Powell ave . The developed site discharges to the same location. REQUIREMENT # 2 : OFF-SITE ANALYSIS These issues are addressed in Section III . The downstream system appears to be adequate. REQUIREMENT # 3 : RUNOFF CONTROL As stated above, no detention is required, but runoff will be treated thru a bioswale and a water quality swale. REQUIREMENT # 4 : CONVEYANCE SYSTEM • Conveyance is accommodated by a piped storm drain system which drains into a bioswale . This then drains into a flow diverter, which diverts all storms over a 2 year event away from the water quality swale . After flowing through the water quality swale, the runoff is discharged to an existing catch basin in Powell Ave. Every attempt was made to make this connection point as high as possible in order to minimize the possibility of water backing up into the site from Powell Ave . All roof runoff was diverted directly to an existing storm drain stub in order to minimize the flows entering the swales, thus minimizing the required swale widths . Areas around the building are directed into two separate swales before combining into the water quality swale . Thus the flows in all but the overflow system are quite small and were therefor not analyzed in detail . • . REQUIREMENT #5 : EROSION/SEDIMENTATION CONTROL Sediment runoff from the site will be controlled thru standard measures, including silt fences, a gravel construction entrance, and use of a small pond for sediment collection during construction. This pond consists of the water quality swale, which is below grade and will provide excellent opportunity for sedimentation. See Section IX for a complete design. SPECIAL REQUIREMENTS The only special requirement applicable to this project is Number 5, and deals with special treatment due to the proximity of sensitive streams . The manner in which this issue was handled was discussed above . • • • SECTION III • OFF-SITE ANALYSIS • OFF-SITE ANALYSIS Because of the simplicity of the downstream conditions, a detailed downstream analysis was not done . After discharging into the system in Powell Ave . , the runoff is carried to a deep east-west swale . This swale is about 8 feet across at the base and sidewalls of about 2H: 1V slope. The swale is vegetated and not suffering any apparent erosion or sedimentation problems . Before connecting to the P-1 Channel, the swale crosses under Naches Ave . in a 60 inch CMP, where it combines with runoff coming down that street . No upstream areas drain onto the subject site, as it is surrounded by developed properties, which control runoff on their respective sites . • • SECTION V CONVEYANCE SYSTEMS ANALYSIS AND DESIGN 4.l v- C, (i W W W W W W O O O tn O O H r _ 1 ,' f r (f a^ W t�.1-v t(� QV G-`�, f W CL CrCiCr nnn t, GG_� P° < f L.o L� s T rJ u_e1 F t��n { �`e e..r �Sp.•�! t� C c� Sr S zoo 4r-eo, (4D 5 t r,tAp��vt�cusr. 3g, ✓7 lJ 3 5— d. 2/ 3/95 Site Development Services page 1 Powell Ave Warehouse --------------------------------------------------------------------- --------------------------------------------------------------------- • BASIN SUMMARY 3ASIN ID : a100 NAME : Water Quality Swale Design SBUH METHODOLOGY -'--- TOTAL AREA. . . . . . . : 2 . 07 Acres BASEFLOWS : 0 . 00 cfs RAINFALL TYPE. . . . : TYPElA PERVIOUS AREA PRECIPITATION. . . . : 3 . 90 inches AREA. . : 0 . 69 Acres TIME INTERVAL. . . . : 10 . 00 min CN. . . . : 86 . 00 TIME OF CONC. . . . . : 7 . 65 min IMPERVIOUS AREA ABSTRACTION COEFF : 0 . 20 AREA. . : 1 . 38 Acres CN. . . . . 98 . 00 TcReach - Sheet L: 80 . 00 ns : 0 . 0110 p2yr: 2 . 00 s : 0 . 0120 TcReach - Channel L: 430 . 00 kc: 42 . 00 s : 0 . 0050 TcReach - Channel L: 123 . 00 kc: 17 . 00 s : 0 . 0050 TcReach - Channel L: 200 . 00 kc : 17 . 00 s : 0 . 0100 PEAK RATE : 1 . 49 cfs VOL: 0 . 56 Ac-ft TIME 480 min BASIN ID: a25yr NAME : Water Quality Swale Design SBUH METHODOLOGY TOTAL AREA. . . . . . . : 2 . 07 Acres BASEFLOWS : 0 . 00 cfs RAINFALL TYPE . . . . : TYPElA PERVIOUS AREA PRECIPITATION. . . . : 3 .40 inches AREA. . : 0 . 69 Acres TIME INTERVAL. . . . : 10 . 00 min CN. . . . : 86 . 00 TIME OF CONC. . . . . : 7 . 65 min IMPERVIOUS AREA • ABSTRACTION COEFF: 0 . 20 AREA. . : 1 . 38 Acres CN. . . . : 98 . 00 TcReach Sheet L : 80 . 00 ns : 0 . 0110 p2yr. 2 . 00 s : 0 . 0120 TcReach - Channel L : 430 . 00 kc: 42 . 00 s : 0 . 0050 TcReach - Channel L : 123 . 00 kc: 17 . 00 s : 0 . 0050 TcReach - Channel L : 200 . 00 kc: 17 . 00 s : 0 . 0100 PEAK RATE : �1 cfs VOL: 0 . 48 Ac-ft TIME: 480 min ,� :f V- BASIN ID: a2yr NAME : Water Quality Swale Flows SBUH METHODOLOGY TOTAL AREA. . . . . . . : 2 . 07 Acres BASEFLOWS : 0 . 00 cfs =RAINFALL TYPE . . . . : TYPEIA PERVIOUS AREA PRECIPITATION. . . . : 2 . 00 inches AREA. . : 0 . 69 Acres TIME INTERVAL. . . . : 10 . 00 min CN. . . . : 86 . 00 TIME OF CONC. . . . . : 7 . 65 min IMPERVIOUS AREA BSTRACTION COEFF: 0 . 20 AREA. . : 1 . 38 Acres CN. . . . . 98 . 00 TcReach - Sheet L : 80 . 00 ns : 0 . 0110 p2yr: 2 . 00 s : 0 . 0120 TcReach - Channel L : 430 . 00 kc :'2 . 00 s : 0 . 0050 TcReach - Channel L : 123 . 00 kc : 17 . 00 s : 0 . 0050 TcReach - Channel L : 200 . 00 kc : 17 . 00 s : 0 . 0100 PEAK RATE : 0 . 67 cfs VOL : C . 25 Ac-ft TIME : 480 min Trapezoidal Channel Analysis & Design • Open Channel - Uniform flow Worksheet Name : Powell Ave Warehouse Comment : Water Quality Swale - 2 Year Flow F", W 'e`^`^�� �^G- ,` U `� Solve For Bottom Width Given Input Data : Left Side Slope . . 3 . 00 : 1 (H:V) Right Side Slope . 3 . 00 : 1 (H:V) Manning' s n. . . . . . 0 .350 Channel Slope. . . . 0 . 0200 ft/ft Depth. . . . . . . . . . . . 0 . 25 ft Discharge . . . . . . . . 0 . 67 cfs Computed Results : ✓fie �1 i'rfc� �-� � �. �-t_, Bottom Width. . . . 11 . 02 ft Velocity. . . . . . . . . 0 . 23 fps Flow Area. . . . . . . . 2 . 94 sf Flow Top Width. . . 12 . 52 ft Wetted Perimeter . 12 . 60 ft Critical Depth. . . 0 . 05 ft • Critical Slope . . . 4 . 9324 ft/ft Froude Number. . . . 0 . 08 (flow is Subcritical) Open Channel Flow Module, Version 3 .41 (c) 1991 Haestad Methods, Inc . * 37 Brookside Rd * Waterbury, Ct 06708 • Trapezoidal Channel Analysis & Design • Open Channel - Uniform flow Worksheet Name : Powell Ave Warehouse Comment : Water Quality Swale - Check Velocity Solve For Depth Given Input Data: Bottom Width. . . . . 11 . 00 ft Left Side Slope . . 3 . 00 : 1 (H:V) Right Side Slope . 3 . 00 : 1 (H:V) Manning' s n. . . . . . 0 . 080 Channel Slope . . . . 0 . 0100 ft/ft Discharge . . . . . . . . 0 . 67 cfs Computed Results : Depth. . . . . . . . . . . . 0 . 13 ft Velocity. . . . . . . . . 0 .46 fps 1, 0 ./ Flow Area. . . . . . . . 1 . 46 sf / Flow Top Width. . . 11 . 77 ft Wetted Perimeter. 11 . 81 ft • Critical Depth. . . 0 . 05 ft Critical Slope . . . 0 . 2576 ft/ft Froude Number. . . . 0 . 23 (flow is Subcritical) Coen Channel Flow Module, Version 3 .41 (c) 1991 Haestad Methods, Inc . * 37 Brookside Rd * Waterbury, Ct 06708 V� l�� �� V.•L'��i �•.c�l l,t..� �.J a �='�' C't � • � ltil CAL L vO J to to N W W W "2 0 u N 04 It N N N N N N 0 \) o ('1 r Z s- . 'T{V �— �;. ( Y •l, 4�r`t i `} \.. v�✓ t �. �f � C.. ! ,t C r• (r• Q4,f��� a, 9) t (0.72¢i4e—y i• Z . t t 7 n . l,Jf'S� Su1c� ��_ � : Rr rr. (�ct.�,Jc•��yl � ``.i^S ��:,' :1 ;.a:s 7 7 �� (c• F�ocJ= Lj t J i �--`C. 1�l�l� ✓(f�Cr lam-S� �V �l.� C(^ r r G�.��-' �r/' �r '.I�, _. ��-e"'.c �t^G !r ll lr`^ t r^ � � t• ��..�•t�n �, / r C GS�'V•� � v �J�J�� r r W W W h 0 000 N a vaa rrr �� ��v�'vv� - d• z 4 w1 V It k -e ei-`5- ru t,vt %I-A V z • �a-c-�s Z CrC (.✓ a i. ��— S v� �- c. < �' ��� t�.�;� ¢.� p� �c. Z.(.')C3 � — Pv�cQ C7 ( � r � i l0L cCL,- �c ���rL!`� o.� c '�- ors v ' = d. e � ' -,� ►�zp�� � °' 2/ 4/95 Site Development Services page 1 Powell Ave Warehouse --------------------------------------------------------------------- --------------------------------------------------------------------- • BASIN SUMMARY BASIN ID: e100 NAME : Easterly Swale Design SBUH METHODOLOGY TOTAL AREA. . . . . . . : 0 . 73 Acres BASEFLOWS : 0 . 00 cfs RAINFALL TYPE . . . . : TYPEIA PERVIOUS AREA PRECIPITATION. . . . : 3 . 90 inches AREA. . : 0 . 24 Acres TIME INTERVAL. . . . : 10 . 00 min CN. . . . : 86 . 00 TIME OF CONC. . . . . : 6 . 30 min IMPERVIOUS AREA ABSTRACTION COEFF : 0 . 20 AREA. . : 0 . 49 Acres CN. . . . . 98 . 00 PEAK RATE : 0 .53 cfs VOL : 0 . 2/0 Ac-ft TIME : 480 min BASIN ID: e25yr NAME : Easterly Swale Design SBUH METHODOLOGY TOTAL AREA. . . . . . . : 0 . 73 Acres BASEFLOWS : 0 . 00 cfs RAINFALL TYPE . . . . : TYPEIA PERVIOUS AREA PRECIPITATION. . . . : 3 .40 inches AREA. . : 0 . 24 Acres TIME INTERVAL. . . . : 10 . 00 min CN. . . . : 86 . 00 TIME OF CONC . . . . . : 6 . 30 min IMPERVIOUS AREA • ABSTRACTION COEFF: 0 . 20 AREA. . : 0 .49 Acres CN. . . . : 98 . 00 PEAK RATE : 0 .45 cfs VOL: 0 . 17 Ac-ft TIME : 480 min _ � .2,Y- f cri' (t, a4_ vs?J� BASIN ID: e2yr NAME : Easterly Swale Design SBUH METHODOLOGY TOTAL AREA. . . . . . . : 0 . 73 Acres BASEFLOWS : 0 . 00 cfs RAINFALL TYPE . . . . : TYPEIA PERVIOUS AREA PRECIPITATION. . . . : 2 . 00 inches AREA. . : 0 . 24 Acres TIME INTERVAL. . . . : 10 . 00 min CN. . . . : 86 . 00 TIME OF CONC. . . . . : 6 . 30 min IMPERVIOUS AREA ABSTRACTION COEFF: 0 . 20 AREA. . : 0 . 49 Acres CN. . . . : 98 . 00 PEAK RATE : 0 . 24 cfs VOL : 0 . 09 Ac-ft TIME : 480 min �- -2-y�- � 4 cc1 • Trapezoidal Channel Analysis & Design Open Channel - Uniform flow Worksheet Name : Powell Ave Warehouse Comment : Easterly Swale - 2 Year Flow Solve For Bottom Width Given Input Data: Left Side Slope . . 3 . 00 : 1 (H:V) Right Side Slope. 3 . 00 : 1 (H:V) Manning' s n. . . . . . 0 . 350 Channel Slope . . . . 0 . 0200 ft/ft Depth. . . . . . . . . . . . 0 . 33 ft Discharge . . . . . . . . 0 . 24 cfs Computed Results : Bottom Width. . . . 2 . 11 ft Velocity. . . . . . . . . 0 .23 fps Flow Area. . . . . . . . 1 . 02 sf Flow Top Width. . . 4 . 09 ft Wetted Perimeter. 4 . 20 ft • Critical Depth. . . 0 . 07 ft Critical Slope . . . 4 .4921 ft/ft Froude Number. . . . 0. 08 (flow is Subcritical) Open Channel Flow Module, Version 3 .41 (c) 1991 • Haestad Methods, Inc . * 37 Brookside Rd * Waterbury, Ct 06708 Trapezoidal Channel Analysis & Design • Open Channel - Uniform flow Worksheet Name : Powell Ave Warehouse Comment : Easterly Swale - Check Velocity Solve For Depth Given Input Data: Bottom Width. . . . . 2 . 11 ft Left Side Slope . . 3 . 00 : 1 (H:V) Right Side Slope . 3 . 00 : 1 (H:V) Manning' s n. . . . . . 0 . 080 Channel Slope . . . . 0 . 0050 ft/ft Discharge . . . . . . . . 0 .24 cfs Computed Results : Depth. . . . . . . . . . . . 0 . 22 ft Velocity. . . . . . . . . 0 .40 fps < 1,S- �s Flow Area. . . . . . . . 0 . 59 sf ©(cv Flow Top Width. . . 3 .40 ft Wetted Perimeter. 3 .47 ft Critical Depth. . . 0 . 07 ft • Critical Slope . . . 0 . 2346 ft/ft Froude Number. . . . 0 . 17 (flow is Subcritical) Open Channel Flow Module, Version 3 .41 (c) 1991 Haestad Methods, Inc . * 37 Brookside Rd * Waterbury, Ct 06708 • Trapezoidal Channel Analysis & Design • Open Channel - Uniform flow Worksheet Name : Powell Ave Warehouse Comment : Easterly Swale - Adjust Width Solve For Depth Given Input Data: Bottom Width. . . . . 7 . 15 ft ✓12 b Col Left Side Slope . . 3 . 00 : 1 (H:V) Right Side Slope . 3 . 00 : 1 (H:V) Manning' s n. . . . . . 0 . 080 Channel Slope . . . . 0 . 0050 ft/ft Discharge . . . . . . . . 0 . 24 cfs Computed Results : Depth. . . . . . . . . . . . 0 . 11 ft Velocity. . . . . . . . . 0 . 29 fps Flow Area. . . . . . . . 0 . 82 sf Flow Top Width. . . 7 . 81 ft Wetted Perimeter. 7 . 85 ft Critical Depth. . . 0 . 03 ft • Critical Slope . . . 0 . 2941 ft/ft Froude Number. . . . 0 . 16 (flow is Subcritical) Open Channel Flow Module, Version 3 .41 (c) 1991 Haestad Methods, Inc . * 37 Brookside Rd * Waterbury, Ct 06708 • Trapezoidal Channel Analysis & Design • Open Channel - Uniform flow Worksheet Name : Powell Ave Warehouse Comment : Easterly Swale - 25 Year Flow Solve For Depth Given Input Data: Bottom Width. . . . . 7 . 15 ft Left Side Slope . . 3 . 00 : 1 (H:V) Right Side Slope . 3 . 00 : 1 (H:V) Manning' s n. . . . . . 0 . 080 Channel Slope . . . . 0 . 0050 ft/ft Discharge . . . . . . . . 1 .40 cfs Computed Results : Depth. . . . . . . . . . . . 0 . 31 ft Velocity. . . . . . . . . 0 . 56 fps Flow Area. . . . . . . . 2 . 52 sf Flow Top Width. . . 9 . 02 ft Wetted Perimeter. 9 . 12 ft Critical Depth. . . 0 . 10 ft • Critical Slope . . . 0 . 2021 ft/ft Froude Number. . . . 0 . 19 (flow is Subcritical) Open Channel Flow Module, Version 3 .41 (c) 1991 Haestad Methods, Inc . * 37 Brookside Rd * Waterbury, Ct 06708 • Trapezoidal Channel Analysis & Design • Open Channel - Uniform flow Worksheet Name : Powell Ave Warehouse Comment : Easterly Swale - 100 Year Flow Solve For Depth Given Input Data: Bottom Width. . . . . 7 . 15 ft Left Side Slope . . 3 . 00 : 1 (H:V) Right Side Slope . 3 . 00 : 1 (H:V) Manning' s n. . . . . . 0 . 080 Channel Slope . . . . 0 . 0050 ft/ft Discharge . . . . . . . . 1 . 60 cfs Computed Results : Depth. . . . . . . . . . . . 0 . 34 ft Velocity. . . . . . . . . 0 . 58 fps �� ��.r�(S Flow Area. . . . . . . . 2 . 74 sf Flow Top Width. . . 9 . 17 ft Wetted Perimeter. 9 .28 ft Critical Depth. . . 0 . 11 ft • Critical Slope. . . 0 . 1966 ft/ft Froude Number. . . . 0 . 19 (flow is Subcritical) Open Channel Flow Module, Version 3 .41 (c) 1991 Haestad Methods, Inc . * 37 Brookside Rd * Waterbury, Ct 06708 • { owe r r 1,11�s�Qr� s c,tJG1� �%n4 _ us UA x x x V1 0 0 000 VI O O vaa r r r p f i 4z.(41� r d . 3 3' Cp De rg ' .5 v-v-, r 2/ 4/95 Site Development Services page 2 Powell Ave Warehouse BASIN SUMMARY BASIN ID: w100 NAME : WPstarly Swale Design SBUH METHODOLOGY TOTAL AREA. . . . . . . : 1 . 11 Acres BASEFLOWS : 0 . 00 cfs RAINFALL TYPE . . . . : TYPEIA PERVIOUS AREA PRECIPITATION. . . . : 3 . 90 inches AREA. . : 0 . 22 Acres TIME INTERVAL. . . . : 10 . 00 min CN. . . . : 86 . 00 TIME OF CONC. . . . . : 6 . 30 min IMPERVIOUS AREA ABSTRACTION COEFF: 0 . 20 AREA. . : 0 . 89 Acres CN. . . . . 98 . 00 PEAK RATE : 0 . 84 cfs VOL: 0 . 32 Ac-ft TIME : 480 min r U r p f V 0"!. V n BASIN ID: w25yr NAME : Westerly Swale Design SBUH METHODOLOGY TOTAL AREA. . . . . . . : 1 . 11 Acres BASEFLOWS : 0 . 00 cfs RAINFALL TYPE . . . . : TYPEIA PERVIOUS AREA PRECIPITATION. . . . : 3 .40 inches AREA. . : 0 . 22 Acres TIME INTERVAL. . . . : 10 . 00 min CN. . . . : 86 . 00 TIME OF CONC. . . . . : 6 . 30 min IMPERVIOUS AREA • ABSTRACTION COEFF: 0 . 20 AREA. . : 0 . 89 Acres CN. . . . . 98 . 00 PEAK RATE : 0 . 73 cfs VO/\L: 0 . 27 Afc-ft jT\IME : 480 min !f ? BASIN ID: w2yr NAME : Westerly Swale Design SBUH METHODOLOGY TOTAL AREA. . . . . . . : 1 . 11 Acres BASEFLOWS : 0 . 00 cfs RAINFALL TYPE . . . . : TYPEIA PERVIOUS AREA PRECIPITATION. . . . : 2 . 00 inches AREA. . : 0 . 22 Acres TIME INTERVAL. . . . : 10 . 00 min CN. . . . : 86 . 00 TIME OF CONC. . . . . : 6 . 30 min IMPERVIOUS AREA ABSTRACTION COEFF: 0 . 20 AREA. . : 0 . 89 Acres CN. . . . . 98 . 00 PEAK RATE: 0 . 40 cfs VOL: 0 . 15 Ac-ft TIME : 480 min Trapezoidal Channel Analysis & Design • Open Channel - Uniform flow Worksheet Name : Powell Ave Warehouse Comment : Westerly Swale - 2 Year Flow Solve For Bottom Width Given Input Data: Left Side Slope . . 3 . 00 : 1 (H:V) Right Side Slope . 3 . 00 : 1 (H:V) Manning' s n. . . . . . 0 . 350 Channel Slope . . . . 0 . 0200 ft/ft Depth. . . . . . . . . . . . 0 . 33 ft Discharge . . . . . . . . 0 .40 cfs Computed Results : Bottom Width. . . . 3 . 85 ft Fir L = zoos Velocity. . . . . . . . . 0 . 25 fps Flow Area. . . . . . . . 1 . 60 sf Flow Top Width. . . 5 . 83 ft Wetted Perimeter. 5 . 94 ft Critical Depth. . . 0 . 07 ft • Critical Slope . . . 4 . 4756 ft/ft Froude Number. . . . 0 . 08 (flow is Subcritical) Open Channel Flow Module, Version 3 . 41 (c) 1991 Haestad Methods, Inc . * 37 Brookside Rd * 'rlaterbury, Ct 06708 Trapezoidal Channel Analysis & Design • Open Channel - Uniform flow Worksheet Name : Powell Ave Warehouse Comment : Westerly Swale - Check Velocity Solve For Depth Given Input Data: Bottom Width. . . . . 3 . 85 ft Left Side Slope . . 3 . 00 : 1 (H:V) Right Side Slope . 3 . 00 : 1 (H:V) Manning' s n. . . . . . 0 . 080 Channel Slope . . . . 0 . 0050 ft/ft Discharge . . . . . . . . 0 . 40 cfs Computed Results : Depth. . . . . . . . . . . . 0 . 21 ft Velocity. . . . . . . . . 0 .42 fps -E Flow Area. . . . . . . . 0 . 95 sf i Flow Top Width. . . 5 . 12 ft Wetted Perimeter. 5 . 19 ft Critical Depth . . . 0 . 07 ft • Critical Slope . . . 0 . 2338 ft/ft Froude Number. . . . 0 . 17 (flow is Subcritical) Open Channel Flow Module, Version 3 . 41 (c) 1991 Haestad Methods, Inc . * 37 Brookside Rd * Waterbury, Ct 06-D8 • Trapezoidal Channel Analysis & Design • Open Channel - Uniform flow Worksheet Name : Powell Ave Warehouse Comment : Westerly Swale - Adjust Width Solve For Depth Given Input Data : f Bottom Width. . . . . 8 . 70 ft ✓� ..� '� ?�^� .> �`-t Left Side Slope . . 3 . 00 : 1 (H:V) Right Side Slope . 3 . 00 : 1 (H:V) Manning' s n. . . . . . 0 . 080 Channel Slope . . . . 0 . 0050 ft/ft Discharge . . . . . . . . 0 . 40 cfs Computed Results : Depth. . . . . . . . . . . . 0 . 13 ft Velocity. . . . . . . . . 0 . 33 fps Flow Area. . . . . . . . 1 . 21 sf Flow Top Width. . . 9 . 50 ft Wetted Perimeter. 9 . 54 ft • Critical Depth. . . 0 . 04 ft Critical Slope . . . 0 . 2743 ft/ft Froude Number. . . . 0 . 16 (flow is Subcritical) Open Channel Flow Module, Version 3 . 41 (c) 1991 Haestad Methods, Inc . * 37 Brookside Rd * Waterbury, Ct 06708 • Trapezoidal Channel Analysis & Design • Open Channel - Uniform flow Worksheet Name : Powell Ave Warehouse Comment : Westerly Swale - 25 Year Flow Solve For Depth Given Input Data: Bottom Width. . . . . 8 . 70 ft Left Side Slope . . 3 . 00 : 1 (H:V) Right Side Slope. 3 . 00 : 1 (H:V) Manning' s n. . . . . . 0 . 080 Channel Slope . . . . 0 . 0050 ft/ft Discharge . . . . . . . . 2 . 30 cfs Computed Results : Depth. . . . . . . . . . . . 0 . 37 ft Velocity. . . . . . . . . 0 . 63 fps Flow Area. . . . . . . . 3 . 66 sf Flow Top Width. . . 10 . 94 ft Wetted Perimeter. 11 . 06 ft Critical Depth. . . 0 . 13 ft • Critical Slope . . . 0 . 1891 ft/ft Froude Number. . . . 0 . 19 (flow is Subcritical) Open Channel Flow Module, Version 3 .41 (c) 1991 Haestad Methods, Inc . * 37 Brookside Rd * Waterbury, Ct 06708 • Trapezoidal Channel Analysis & Design Open Channel - Uniform flow Worksheet Name : Powell Ave Warehouse Comment : Westerly Swale - 100 Year Flow Solve For Depth Given Input Data: Bottom Width. . . . . 8 . 70 ft Left Side Slope . . 3 . 00 : 1 (H:V) Right Side Slope . 3 . 00 : 1 (H:V) Manning' s n. . . . . . 0 . 080 Channel Slope . . . . 0 . 0050 ft/ft Discharge . . . . . . . . 2 . 70 cfs Computed Results : Depth. . . . . . . . . . . . 0 .41 ft < U �V) 2. S�yY' Velocity. . . . . . . . . 0 . 66 fps � re (5 Flow Area. . . . . . . . 4 . 06 sf Flow Top Width. . . 11 . 16 ft Wetted Perimeter. 11 . 29 ft Critical Depth. . . 0 . 14 ft • Critical Slope . . . 0 . 1829 ft/ft Froude Number. . . . 3 . 19 (flow is Subcritical) Open Channel Flow Module, Version 3 .41 (c) 1991 Haestad Methods, Inc . * 37 Brookside Rd * Waterbury, Ct 06708 • r� LV t C .� W W W __ 0 Vf Vm �100 —i N � CiC4�t N a aaa rc5r �� N N N a < �F • • SECTION IX EROSION/SEDIMENTATION CONTROL DESIGN Jc't'dl`titicc,`� Y �vl G1 � f ��rN ^ o ro V' v�C� r, I ell L -53 ��ro l K � �e V Q � �J �or .°� = �Crb � = S`2(� Lc=J o W W UA N 1/f 1A coo An o o r aaa CI CI CI 71 CI CI CI �n ®f �L7 1.V� �. ✓ c� C- ) � `�^--1� 7Z �+ c a. �4 Y' o c- , �f • r V C V (Cl t o ! O I— (�v--,e c 2 l O 1i-c- C .t_ SECTION X BOND QUANTITIES AND OTHER FORMS •