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Drainage and Erosion Control Report 2004GLACIER NORTHWEST Drainage and Erosion Control Report Proponent: Glacier Northwest Thomas G. Hanson, P.E. Manager Washington Division Environmental P.O. Box 1730 Seattle, WA 98111 Phone: (206) 768-7612 Fax. (206) 764-3012 Prepared By: Robert E. Tauscher, P.E. Jerome W. Morrissette & Associates Inc., P.S. 1700 Cooper Point Road SW, #B2 Olympia, WA 98502 Phone: (360) 352-9456 Fax. (360) 352-9990 Submitted: March 2004 TABLE OF CONTENTS L DRAINAGE REPORT Section 1 - Project Description 1 Section 2 - Existing Conditions 2 Section 3 - Infiltration Rate/Soils Report 2 Section 4 - Wells 2 Section 5 - Fuel Tanks 2 Section 6 - Sub -basin Description 2 Section 7 - 100 Year Flood 3 Section 8 - Aesthetic Considerations 3 Section 9 - Facility Sizing and Downstream Analysis 3 Section 10 - Covenants, Dedications, and Easements 4 Section 11 - Articles of Incorporation 4 II. EROSION CONTROL REPORT Section 1 - Sequence 5 Section 2 - Trapping Sediment 5 Section 3 - Permanent Erosion Control 5 Section 4 - Geotechnical Report 6 Section 5 - Inspection 6 Section 6 - Control of Pollutants Other than Sediment 6 III. APPENDIX A. Soils Report B. Hydraulic Analysis C. Thurston Region Stormwater Facilities Summary F. Basin Map F. Site Plan Glacier NW Preliminary Drainage and Erosion Control Report JWM&A # 04112 PROJECT ENGINEER'S CERTIFICATE "I HEREBY CERTIFY THAT THIS PROJECT, GLACIER NW, YELM, WASHINGTON HAS BEEN PREPARED BY ME OR UNDER MY SUPERVISION AND MEETS MINIMUM STANDARDS OF THE CITY OF YELM AND NORMAL STANDARDS OF ENGINEERING PRACTICE. I UNDERSTAND THAT THE JURISDICTION DOES NOT AND WILL NOT ASSUME LIABILITY FOR THE SUFFICIENCY, SUITABILITY, OR PERFORMANCE OF DRAINAGE FACILITIES DESIGNED BY ME." 66ETa of 4� �� I Robert E. Tauscher, P.E. Jerome W. Morrissette & Associates Inc., P.S. GIacier NW Preliminary Drainage and Erosion Control Report JWM&A # 04112 \4S ICLAL� aFIRES.0:VV L? ii GLACIER NW CIVII., SITE IMPROVEMENTS YELM, WASHINGTON STORM DRAINAGE AND EROSION CONTROL REPORT PART I. DRAINAGE REPORT This report has been prepared as part of the requirements for the Construction Plan Review for the subject site in accordance with the City of Yelm requirements. Section 1- Project Description: The proposed improvements consists adding concrete pavement pads to direct water for reuse on the 5.0 acre site. The site is located on the west side of Rhoton Road SE in Yelm, Washington, in the Southeast quarter (SE %4) of the Northwest quarter (NW %4) of Section nineteen (19), Township seventeen (17) North, Range two (2) East. The property currently is developed with a concrete batch plant. The site is relatively flat. Attached in Appendix F is a copy of the basin analysis developed for the Glacier NW site. Site access will be via an entrance off of Rhoton Road SW. The entrance is located approximately 900 feet north of the intersection of Photon Road SE and N.P. Road SE. The SCS Soil survey maps this area as a Spanaway gravely sandy loam is excessively draining. The design infiltration rate is 20 inches/hour. This pond is located on the east side of the lot. The intent of the stormwater drainage plan is to provide additional facilities to the site that will prevent the wash water from various process and manufacturing areas from entering the stormwater infiltration facilities and bare ground without treatment, and to prevent stormwater runoff drainage from non -contact areas from mixing with wash water and Portland cement that could enter the infiltration facilities. The proposed additional concrete paving is intended to better control the runoff and direct it to a holding basin to be pump back into the system for reuse. Section 2 - Existing Conditions: Glacier NW Drainage and Erosion Control Report JWM&A # 04112 The existing site is developed with the runoff is currently sheet flowing towards a Pond at the northeast comer of the parcel. The east portion of the property contains storage area for concrete product curing area. The site, measuring approximately 634' x 330', has moderately flat to flat slopes with an elevation change from 332 feet at the southwestern corner and 327 at the northeastern boundary. Section 3 - Infiltration Rates/Soils Report: Soils on the site are Iisted in the Soil Conservation Service's Soil Survey of Thurston County Washington as Spanaway gravely sandy loam (see attached Appendix A). Typical soils are a black gravely sand near the surface with dark yellowish brown very gravelly loam occurring within two feet of surface. Soil mapping indicates that the predominant soil group at this site is `B". An evaluation of the surficial soils was conducted and a copy of the soils information is located in Appendix A. The soils report confirms the soil survey mapping. The soil logs typically indicate sandy gravel to 18-84". The infiltration rate measured in a falling head test performed 36 inches below the existing surface is between 46 and 59 inches per hour. A description of the.falling head infiltration test device used to perform the percolation test and the infiltration tests results are found in the Soils Report in Attachment A. Using standard design practice with a factor of safety of two, a design infiltration rate of 20 in/hr is used for design. Section 4 - Wells: A search on the Thurston County Geodata web site was conducted to identify existing groundwater wells in the vicinity of the proposed project {see attached Appendix Q. There are no ]mown wells within or near the site. Most residential and commercial lots are served with city water. No wells will be drilled for these improvements. Section 5 - Fuel Tanks: There is a covered fuel and storage building on the south property line. No additional fuel tanks will be brought onto the property or installed during these improvements. Section 6 — Sub -basin Description: The sub -basin that contains this site is approximately 5.0 acres in size. A complete sub -basin analysis was conducted for this project and a copy is located in Appendix F. Glacier NW Drainage and Erosion Control Report 7WM&A # 04112 Section 7 - 100 Year Flood: The project does not contain or abut a stream and is not in a flood zone. Section 8 - Aesthetic Considerations; In general, the overall aesthetic affect of the stormwater facilities on this site will be consistent with, if not more pleasing than, neighboring areas and should not detract from surrounding areas. Section 9 — Facility Sizing and Downstream Analysis: All stormwater conveyance and detention systems were designed for the 100 Year/24 Hour Design Event. The hydraulic analysis for the on-site stormwater facilities may be found in Appendix B. The evaluation performed include pond storage and HYDRA analyses (HYDRA Version 5.85, July 1994). Copies of the HYDRA Input and Output files and tables summarizing the site area and pond volume characteristics are included in Appendix B. POST IMPROVEMENT SITE CHARACTERISTICS Total Site Area 5.00 Acres Pass -Through Drainage Area 0 Acres Pond Tributary Area 5.00 Acres Parking and Other Impervious Area 4.15 Acres Pervious Area (Lawn and Landscape) 0.86 Acres SCS Data Hydrologic Soil Group `B" Curve Numbers Impervious Areas 98 Landscaped Pervious Areas 85 SYSTEM MINIMUM REQUIREMENTS Min. Stor. Volume Req. Stor. Volume per HYDRA Stormwater Volume provided Settling Pond Volume Design Infiltration Rate System Performance 13,300 CF 14,410 CF 18,781 CF 4,257 CF 1.70 CFS at 20 in/hr with 3,680 sf pond bottom Glacier NW 3 Drainage and Erosion Control Report JWM&A # 04112 Based on the HYDRA analyses performed for the 100 Year/24 Hour - Design Event, the peak flow into the stormwater pond will be 4.50 CFS. The maximum storage expected in the pond per HYDRA is 14,410 CF, the design infiltration rate 1.70 CFS with a 3,680 SF pond bottom, with a combined volume provided including the settling basin, infiltration pond. holding basin and concrete re -use tanks of 15,781 CF. Downstream analyses are not included in this report, as all stormwater is being detained and infiltrated on site. Section 10 - Covenants, Dedications, Easements: Operation and maintenance of the stormwater pond, settling pond and swales will be the responsibility of the property owner. A Commercial/Industrial stormwater facilities maintenance agreement prepared for this site is located in Appendix D. Section 11 - Articles of Incorporation: The parcel will be privately owned, Articles of Incorporation are not required. Glacier NW 4 Drainage and Erosion Control Report 7WM&A # 04112 PART H. EROSION CONTROL REPORT Section 1- Sequence: The following is the construction sequence for construction of the roadway and the pond. 1. Rough grade proposed concrete pads. 2. Once disturbed surfaces have developed suitable groundcover, remove perimeter silt fences. Section 2 - Trapping Sediment: The proposed grading of the site, as well as the construction of the items listed below, will mitigate against any major diversion of stormwater runoff by maintaining natural drainage patterns. The structural components of the erosion control plan will work in combination with temporary and permanent soil stabilization efforts to minimize the amount of sediment -laden runoff entering adjacent properties and the existing on-site wetlands. Measures Taken to Control Sediment: Entrance is currently concrete pavement for the point of egress during the construction of the civil site improvements. Permanent sediment trapping will be accomplished in the swale, where vegetation will cause soil particles to drop out of solution as the stormwater passes through the area. The current entrance is concrete pavement off of Rhoton Road SE at the location of the existing driveway on the plans. The concrete pavement entrance should reduce any loss of soil due to vehicle tracking. If a substantial amount of soil is being deposited on Rhoton Road SE due to truck traffic, the road will immediately be cleaned of all debris and further preventative measures will be taken to ensure the problem ceases, such as establishing a tire wash down area. All of the above features of the Erosion and Sedimentation Control Plan, if installed and periodically maintained, are expected to minimize the potential for sediment -laden runoff escaping the site and entering the downstream environment during and after the construction of the project. Section 3 - Permanent Erosion Control: Glacier NW Drainage and Erosion Control Report JWM&A # 04112 The following measures will be taken for soil stabilization to minimize the amount of sediment-Iaden runoff entering adjacent properties and the existing on- site wetlands. Stabilization of cut and fill areas with hydro seeding and, if necessary, chopped hay mulching (or jute matting). Permanent erosion control on this site will be accomplished through the development of grass groundcover on all unpaved disturbed areas. Section a - Geotechnical Report: There are no other incipiently unstable stormwater related conditions within the project site, hence; no additional soil investigations or analyses are planned. Section 5 - Inspection: The construction of stormwater facilities on the subject site will be monitored by the Owner and the Owner's representative in accordance with the requirements of the Drainage Manual. The following is the recommended inspection sequence for the construction of stormwater facilities described above: I . At completion of rough grading. 2. At completion of the pond. Upon completion of the project, the "Engineer's Construction Inspection Report Form" will be completed by the Licensed Professional Engineer responsible for providing the above listed inspection services and submitted to the City of Yelm. Section 6 - Control of Pollutants Other Than Sediments: Temporary pollutant sources, such as cement truck wash -down waste, fuel spillage during equipment refueling, and commercial construction waste materials may develop for short periods during the construction of the roadways, utilities, stormwater facilities and structures. Care will be taken to minimize the adverse impacts of these conditions. Activities such as concrete truck wash -down and equipment refueling will be carried out in the vicinity of structure construction, at least 25 feet from the stormwater facilities. Construction material stockpile areas should be limited to the immediate vicinity of the commercial buildings being constructed. Bulk petrochemical storage, in the Glacier NW Drainage and Erosion Control Report JWM&A # 04112 form of gasoline, fuel, oil, lubricants, and other such hazardous fluids will not be permitted on this site. Glacier NW Drainage and Erosion Control Report JWM&A # 04112 APPENDIX A Soils Report APPENDIX A Soils Report * ILLT- Thurston County, Washington 89 ncluded areas make up about 10 percent of the total acreage. Permeability is moderately rapid in the Spana soil. Wailabie water capacity is moderate. Effective rooting iepth is 20 to 40 inches. A seasonal high water table is it a depth of about 12 to 36 inches from November to kpril. Runoff is slow, and the hazard of water erosion is ;light. Most areas are used as hayiand and pasture. This snit is suited to hay and pasture. The main limitations ire the seasonal high water table and the moderate rvailable water capacity. Proper-steciring-rates;-pasture otation, and restricted grazing during wet periods help o keep the pasture in good condition and protect the ;oil from erosion..Rotation grazing helps to maintain the luality of forage. Periodic mowing helps to maintain iniform growth, discourages selective grazing, and ;ontrols weeds. In most years irrigation is needed for naximum production. Sprinkler irrigation is the best nethod of applying water. The amount of water applied ;hould be sufficient to wet the root zone but small :Hough to minimize the leaching of plant nutrients. . A few ,areas are used as woodland. On the basis of a 00 -year site curve, the estimated site index for )ouglas-fir is 144:^On the basis of a 50 -year site curve, I is 110. The estimated growth rate of an unmanaged, wen -aged stand of Douglas -fir is 150 cubic feet per acre per year at 60 years of age. The main limitation affecting the harvesting of timber s the muddiness caused by seasonal wetness. Use of vheeled and tracked equipment when the soil is wet esults in ruts and soil compaction. Unsurfaced roads ind skid trails are soft and can be impassable when vet. Logging roads require suitable surfacing material or year-round use. Rounded pebbles and cobbles for cad construction are readily available on this unit. The seasonal high water table limits the use of equipment to fry. periods. Disturbance of.the-pptective layer of duff :an be minimized by the careful use of wheeled and narked equipment. - -- -- Seedling establishment is the main concern in the production of timber. Reforestation can be Lccomplished by planting Douglas -fir seedlings. If the ;tand includes seed trees, natural reforestation by red alder occurs periodically in cutover areas. The seasonal sigh water table inhibits root respiration and thus results n some seedling mortality. When openings are made in he canopy, invading brushy plants can prevent the -stablishment of planted Douglas -fir seedlings. Common forest understory plants are cascade )regon-grape, salal, vine maple, western brackenfern, ind Oregon white oak. This map unit is in capability subclass lllw. 110—Spanaway gravelly sandy loam, 0 to 3 percent slopes. This very deep, somewhat excessively drained soil is an terraces. It formed in glacial outwash and volcanic ash. The native vegetation is mainly grasses, Ferns, and a few conifers. Elevation is 100 to 400 feet. The average annual precipitation is 45 to 55 inches, the average annual air temperature is about 51 degrees F, and the average frost -free period is 150 to 200 days. Typieafly,- he-surfeee layer-iek gravelly sandy loam about 15 inches thick. The subsoil is dark yellowish brown very gravelly loam about 5 inches thick, The substratum to a depth of 60 inches or more is dark yellowish brown extremely gravelly sand. Included in this unit are small areas of Alderwood soils on till plains; Everett, Indianola, and Nisqually soils on outwash terraces; and Spana soils in depressions. . Also included are small areas of Spanaway soils that have a stony sandy loam surface layer and small areas of Spanaway gravelly sandy loam that have slopes of 3 to 15 percent. Included areas make up about 20 percent of the total acreage. Permeability is moderately rapid in the subsoil of the Spanaway soil and very rapid in the substratum. Available water capacity is low. Effective rooting depth is 60 inches or more. Runoff is slow, and the hazard of water erosion is slight. This unit is used mainly as hayiand, pasture, or cropland, as a site for homes, or as a source of gravel. It is also used ais woodland. The main limitation affecting hay and pasture is the low available water capacity. Proper grazing practices, weed control, and fertilizer are needed to ensure maximum quality of forage. Rotation grazing helps to maintain the quality of forage. Periodic mowing helps to maintain uniform growth, discourages selective grazing, and controls weeds. Animal manure can be applied _periodically during the g_r.Q g season. Areas that receive heavy applications should be harrowed at least once a year. In summer, irrigation is needed for maximum production of most forage crops. Sprinkler irrigation is the best method of applying water. The amount of water applied should be sufficient to wet the root zone but small enough to minimize the leaching of plant nutrients. This unit is suited to crops. Wheat, oats, strawberries, raspberries, blackberries, and sweet corn are commonly grown. The main limitation is the low available water capacity. In summer, irrigation is needed for maximum production of most crops. Sprinklers can be used, but a slow application rate is needed to minimize runoff. The amount of water applied should be sufficient to wet the root zone but small enough to minimize the leaching of plant nutrients. The application rate should be adjusted to the available water capacity, the water intake rate, and the needs of the crop. Animal manure can be applied periodically during the growing season. Areas that receive heavy applications should be harrowed at least once a year. This unit is well suited to homesites. Pebbles and cobbles should be removed, particularly in areas used for lawns. In summer, irrigation is needed for lawn grasses, shrubs, vines, shade trees, and ornamental trees. Mulch, fertilizer, and irrigation are rrereded`t'tr` - establish lawn grasses and other small -seeded plants. The main limitation affecting septic tank absorption fields is a poor filtering capacity. If the density of housing is moderate or high, community sewage systems are needed to prevent the contamination of water supplies caused by seepage from onsite sewage disposal systems. Cutbanks are not stable and are subject to sloughing. Douglas -fir is the main woodland species on this unit. Among the trees of limited extent are Oregon white oak, lodgepole pine, and red alder. Douglas -fir and Scotch pine are grown on Christmas tree plantations. On the basis of a 100 -year site curve, the mean site index for Douglas -fir is 140. On the basis of a 50 -year site curve, it is 106. The highest average growth rate of an unmanaged, even -aged stand of Douglas -fir is 145 cubic feet per acre per year at 65 years of age. This soil is suited to year-round logging. Unsurfaced roads and skid trails are slippery when wet. Logging roads require suitable surfacing material for year-round use. Rounded pebbles and cobbles for road construction are readily available on this unit. Disturbance of the protective layer of duff can be minimized by the careful use of wheeled and tracked equipment. Seedling establishment and seedling mortality are the main concerns in the production of timber. Reforestation can be accomplished by plantiag-Douglas4ir seedlingS__. _ If the stand includes seed trees, natural reforestation by Douglas -fir, Oregon white oak, and lodgepole pine occurs periodically in cutover area's. Droughtiness in the surface layer reduces the seedling survival rate. When openings are made in the canopy, invading brushy plants can delay the establishment of planted Douglas - fir seedlings. Common forest understory plants are cascade Oregon -grape, salal, western brackenfern, western swordfern, Indian plum, and Scotch -broom. Soil Survey This map unit is in capability subclass IVs. 111—Spanaway gravelly sandy loam, 3 to 15 percent slopes. This very deep, somewhat excessivel, drained soil is on terraces. It formed in glacial outwash and volcanic ash. The native vegetation is mainly grasses, ferns, and a few conifers. Elevation is 100 to 400 feet. The average annual precipitation is 45 to 55 inches, the average annual air temperature is about 51 degrees F, and the average frost -free period is 150 to 200 days. Typically, the surface layer is black gravelly sandy loam about 15 inches thick. The subsoil is dark You wisirbrowrrvery -gravefly -- inches thick. The substratum to a depth of 60 inches or more is dark yellowish brown extremely gravelly sand. Included in this unit are small areas of Alderwood soils on till plains and Everett, Indianola, and Nisqually soils on terraces. Also included are small areas of Spanaway soils that have a stony sandy loam surface layer and small areas of Spanaway gravelly sandy loan that have slopes of 0 to 3 percent: Included areas mak, up about 20 percent of the total acreage. Permeability is moderately rapid in the subsoil of the Spanaway soil and very rapid in the substratum. Available water capacity is low. Effective rooting depth is 60 inches or more. Runoff is slow, and the hazard of water erosion is slight. This unit is used mainly as hayland or pasture, as a site for homes, or as a source of gravel. It is also used as woodland. The main limitation affecting hay and pasture is the low available water capacity during the growing season Proper grazing practices, weed control, and fertilizer arc needed to ensure maximum quality of forage. Rotation grazing helps to maintain the quality of forage. Periodic mowing helps to maintain uniform growth, discourages selective grazing, and controls weeds. Animal manure can be applied periodically during the growing season. Areas that receive heavy applications should be harrowed at least once a year. in summer, irrigation is npprlad for maximum p,rortuctirm-aLmQatjorage cmpj. Sprinkler irrigation is the best method of applying water. The amount .of water applied should be sufficient to wet the root zone but small enough to minimize the leachinc of plant nutrients. This unit is suited to homesites. The main limitation is the slope. Cutbanks are not stable and are subject to sloughing. A plant cover can be established and maintained through proper fertilizing, seeding, mulching. and shaping of the slopes. Pebbles and cobbles should' be removed, particularly in areas used for lawns. In 158 Spanaway Series The Spanaway series consists of very deep, somewhat excessively drained soils on terraces. These soils formed in glacial outwash and volcanic ash'. Slope is 0 to 15 percent. Elevation is 100 to 400 feet. The average annual precipitation is 40 to 55 inches, the average annual air temperature is about 51 degrees F, and the average frost -free season is 150 to 200 days. These soils are sandy -skeletal, mixed, mesic Andic Xerumbrepts. Typical pedon of Spanaway gravelly sandy loam, 0 to 3 percent slopes, 4 miles southeast of Lacey; about 250 feet west and 400 feet south of the northeast-saraer--a _ sec. 25. T. 36 N.. R. i W. A-0 to 15 inches; black (10YR 211) gravelly sandy loam, very dark grayish brown (10YR 3/2) dry; weak fine granular structure; loose, very friable, nonsticky and nonplastic: many fine, medium, and coarse ro.ots: 25 percent pebbles; strongly acid; clear smooth boundary. Bw-15 to 20 inches; dark yellowish brown (10YR 3/4) very gravelly sandy loam, light olive brown (2.5Y 5/4) dry; weak fine subangular blocky structure; loose, very friable, nonsticky and nonplastic; many fine, medium, and coarse roots; 55 percent pebbles; medium acid; clear smooth boundary. C-20 to 60 inches; dark yellowish brown (10YR 414) extremely gravelly sand, yellowish brown (10YR 5/4) dry; single grained; loose; few fine roots; 80 percent pebbles, 10 percent cobbles; slightly acid. The thickness of the solum ranges from 15 to 25 inches. The content of coarse fragments in the control section ranges from 50 to 85 percent. The weighted average texture of this section is very gravelly sand or extremely gravelly sand. The umbric epipedon is 10 to 20 inches thick. The A horizon has hue of 10YR or 7.5YR, value of 3 or 4 when dry, and chroma of 1 or 2 when moist or dry. It is medium acid or strongly acid. The Bw horizon has value of 4 or 5 when dry aad_a_ctr_4_wbRa_moist_1t is very gravelly sandy loam, very gravelly loam, or extremely gravelly sandy loam. The C horizon has hue of 10YR or 2.5Y, value of 5 or 6 when dry and 4 or 5 when moist, and chroma of 3 or 4 when dry or moist. It is extremely gravelly sand or extremely gravelly loamy sand and is slightly acid or neutral. Sultan Series The Sultan series consists of very deep, moderately Soil Survei well drained soils on flood plains. These soils formed alluvium- Slope is 0 to 3 percent. Elevation is 20 to 75 feet. The average annual precipitation is 40 to 50 inches, the average annual air temperature is about 51 degrees F, and the average frost -free season is 150 tc 200 days. These soils are fine -silty, mixed, nonacid, mesic Aquic Xerofluvents. Typidal pedon of Sultan silt loam, 7 miles east of Lacey; about 1,000 feet east and 1,975 feet north of P southwest corner of sec. 16, T. 18 N., R. 1 E. Ap-0 to 7 inches; dark yellowish brown (10YR 3/4) sii .leaewrrf;-6'►�R-5f3}-dry;-rRadera#e�e-ar►d--.- medium granular structure; slightly hard, very friable, slightly sticky and slightly plastic; many fine medium, and coarse roots; many very fine and fine tubular pores; slightly acid; abrupt smooth boundary. BA -7 to 20 inches; dark yellowish brown (10YR 4/4) silt loam, brown (10YR 513) dry; moderate fine and medium subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; man) very fine, fine, and medium roots; many very fine and fine tubular pores; slightly acid; clear wavy boundary. Bw1-20 to 25 inches; bark brown (10YR 3/3) silt loam grayish brown (2.5Y 5/2) dry; common fine prominent red (2.5YR 518) mottles; moderate fine and medium subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic: common fine and medium roots; common very fine and fine tubular pores; slightly acid; gradual wavy boundary. Bw2-25 to 45 inches; dark brown (10YR 4/3) silt loam, light brownish gray (10YR 6/2) dry; common medium prominent red (2.5YR 5/8) mottles; moderate medium and coarse subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; few very fine and fine roots; few very fine and fine tubular pores; slightly acid; gradual waw hmndar_y_. - C-45 to 60 inches; grayish brown (10YR 5/2) silt loam, light gray (10YR 7/2) dry; common medium prominent dark brown (7.5YR 4/4) mottles; massive; slightly hard, very friable, slightly sticky and slightly plastic; slightly acid. - The soils are slightly acid or neutral in the control section and range from slightly acid to strongly acid below a depth of 40 inches. Mottles that have chroma of 3 or more are at a depth of more than 20 inches. J I 94TwAL Jerome W. Bloke & Associates Inc., P.S. 1700 Cooper Point Road SW, #B-2, Olympia, WA 9850211/0 (360)352-9456 1 FAX (360)352-9990 Civil / Municipal / Geotechnical Engineering and Planning J It' &LASYLAL Jerome W. Mon satin & Assodates lac., P.S. 1700 Cooper Point Road SW, #&2, Olympia, WA 98502-1110 (360)352-9456 1 FAX (360)352-9M Civil / Municipal / Geoteadnical Engineering and Planning Jerome W. Morrissstie & Associates Inc., P.S. 17011 Cooper Point Read SW, Z alYrmpfa. WA 98sog_.i i in Civil / Municipal / Geotechnical Engineering and Planning I W SP 9 • i .Jerome W. Mortissette $ Associates Inc-, P.S. 1740 Cooper Point Road SW, #B -Z 0 lympla. WA 9854Q-1 110 (360),392-9456 1 FAX 13601GA7-oonq Civil / MunlclPal / Geotechnical Engineenng and Planning APPENDIX B Hydraulic Analysis GLACIER NORTHWEST DRAINAGE SIZING 312TJO4 MINIMUM STORAGE VOLUME Pared 5.0 Acres, Zoned Industrial, SCS Soil Survey - Spanaway gravely. sandy Loam, Group B Table 111-1.3 - Curve Number for Open Spaces - 85 for Soil Group B Curve Number for Impervious - 98 for Soil Group B Pre - Developed EAsting Impervious EAsting Pervious Area Post - Developed New Concrete Pads = EAsting Impervious Not Changed = Undisturbed Pervious Area 86,684 131,116 sf = sf = 1.99 3.01 Acres Acres Total 217,600 sf = 5.00 Acres 94,089 sf = 2A6 Acres 86,684 sf = 1.99 Acres 37,027 sf = 0.85 Acres Total 217,800 sf = 5.00 Acres MINIMUM STORAGE VOLUME REQUIRED Infiltration rate of 20 In/hr with 3680 sf Bottom=1.70cfs discharge Per DDECM Pg 4-5 Minimum Storage Volume Required Per Acre of Disturbed Pervious = 1,000 cf/ac Minimum Storage Volume Required Per Acre of Impervious Pervious = 3,000 cf/ac (1000cf/ac)(0.85ac) + (3000cflac)(4.15ac) = 13,300 cf MINIMUM INFILTRATION VOLUME Pre - Developed [(4.45iN12inIft)(3.01Ac)(43,560sf/Ac)]+[(5.91Intl 21ntft)(1.99Ac)(43,560s(/Ac)] = 91,314 cf Post Developed [(4.451n112iri/ft)(0.85Ac)(43,560sf/Ac)]+[(5,91in/12intft)(4.15Ac)(43,560sf/Ac)] = 102,762 cf Infiltration Volume Required = Post Develop - Pre Developed = 102,762cf - 91,314cf = 11,448 cf HYDRA VOLUME REQUIRED Per HYDRA volume required for 24 hour1100 year event Is 8,865 cf 14,410 cf Controls STORAGE VOLUME PROVIDED Reuse Concrete ponds provide 6,012 cf of volume New Holding Basin provides 1152 cf of volume Pond Size, at top and bottom is 80' x 45, 2 feet deep, ecology block sidewalls, pond bottom area - 3680 sf Volume contour 326 = 3680 SF 3,680 sf Volume contour 324 = 3680 SF 3,680 sf Volume =((3680+3680)12)'2 = Pond 7,360 cf Concrete Reuse Tanks 6,012 cf Proposed New Holding Basin 1,152 cf EAsitng Settling Basin Next to Pond 4,257 cf 18,781 cf > 14,410 cf OK Using 20 inlhr, over a 3680 sf Bottom, Infiltration Rate m 1.70 cis CHECK: POND VOLUME R UIRED TO BE INFILTRATED WITHIN 48 HRS Hrs to Inf Pond = (VoUAreap(Inf Rate) =(14524cU3680sf)(1120in/hr)(12intft) = 3.1 hrs ok Vol Inf in 48 Hrs=(BottomArear(Inf Rate)'48hrs=(3680sf)(20inlhr)(1ft112in)(48hr)= 294,400 cf ok �.,memenui,� awdw nwe,,,i eratme cuci..Hrv,r. CENTRAL REDDI MIX PERCOLATION TEST RESULTS 02136 11/20/02 Percolation Test No.1 Test Number Elapsed Time (Min:Sec) Elapsed Time (Sec) Elapsed Time (Hr) Inches of Water Perked Perc Rate (In1Hr) 1 6:13 373 0.104 6 58 2 6:06 368 0.102 6 59 3 6:35 395 0.110 6 55 4 6:29 369 0.108 6 56 5 7:00 420 0.117 6 51 6 7:17 437 0.121 6 49 7 7:20 440 0.1 22 6 49 8 7:31 451 0.125 6 48 Percolation Test No. 2 Test Number Elapsed Time (MIn:Sec) Elapsed Time (Sec) Elapsed Time (Hr) Inches of Water Perked Pere Rate (In/Hr) 1 6:18 378 0.105 6 57 2 6:44 404 0.112 6 53 3 7:06 426 0.118 6 51 4 7:22 442 0.123 6 49 5 7:44 464 0.129 6 47 6 7:48 468 0.130 6 46 7 7:45 465 0.129 6 46 8 7:53 473 0.131 6 46 P x l r .. � pit _' • * � 1 4 J Fm JOB GLACIER NW - STORMWATER DESIGN REM --- 100 YEAR STORM EVENT FOR DETENTION SIZING TOT 6.15 FIL C:\HYE\1A.INC NEW PARKING LOT STORMWATER TO BIOFILTER CHID 6, 0.3, 0.03, 3, 2, 3, 1.0, 0, 0, 0, 0 SCS 5, 0.83, 98, 85, 20, .01, 220 CRA 50, 327, 323, 326, 323 RED (0/1.7, 7360/1.7) RES 323, 323, 327, OVER MIN C : \HYDRA\CMD\ HYDRA Version 5.85 j.w.morrissette & associates Page 1 C:\HYDRA\CMD\GLA100.CMD 10:01 22 -Mar -104 CFS GLACIER NW - STORMWATER DESIGN *** PARKING LOT STORMWATER TO BIOFIL Channel Long Invert Surf FreBrd Width Shape San Sto Flow Estimated Link Slope Up/Dn Up/Dn Up/Dn Depth L/C/R Inf Mis 'Uel Cost 1 50 326.00 326.33 0.7 3.99 3.000 0.00 4.70 4.70 0 0.0600 323.00 323.33 -0.3 0.33 2.00 0.00 0.00 4.73 3.000 Froude Number 1.67 ---------------------------------------------------- Lateral length= 50 Upstream length= 50 ---------------------------------------------------- Lateral length- 0 Upstream length- 0 *** PARKING LOT STORMWATER TO BIOFIL Reservoir Cost Invert -------------- Maximum Flow Values ----------------- Link Exfil Up/Dn/Ovr San Inf Sto Mis Design 3 0 323.00 Incoming : 0.00 0.00 4.70 0.00 4.70 0 323.00 Discharge : 0.00 0.00 1.70 0.00 1.70 327.00 Overflow 0.00 0.00 0.00 0.00 0.00 Stored 0 0 14410 0 14410 ---------------------------------------------------- Lateral length= 50 Upstream length= 5o C;\HYDRA\CND\ HYDRA Version 5.85 j.w.morrissette & associates Page 1 C:\HYDRA\CMD\GLA100.CMD 10:01 22 -Mar -104 NONE Status of DEFAULTS at start of run. Command file : C:\HYDRA\CND\GLA100.CMD f Input units are read as USA warnings are turned : OFF Output sent to display Detailed Output sent to printer Off Output sent to file Verbose Paper width in inches 8.000 String to reset printer 27 51 36 18 String to set printer to compressed 17 15 String to set printer to B lines/inch 8 27 51 27 Name of printer Epson, FX series f Print heading at top of page ON Number of steps in hydrograph 166 Step length in minutes 60 Significant flow in hydrograph 0.010 Infiltration Diurnalization Factor 0.980 Maximum plot value : Selected by HYDRA Type of hydrographic plot : Compact Sanitary flow by : Diurnal Curve Delay to start of actual storm 0.00 Rational Method computations OFF SGS computations Santa Barbara Continuous simulation computations ON Maximum d/D for pipe design/analysis 0.900 Match point position on pipe 0.00 or Invert Number of allowable diam drops : 999 i Mimimum drop thru manhole 0.000 Manning's n Variable Routing technique Quick Calculate sanitary flows ON Calculate infiltration flows ON Calculate misc flows ON Listing of acceptable diameters (Changed by the PCO command): 4 6 8 10 12 15 18 21 24 27 30 + 33 36 39 42 45 48 54 60 66 72 78 84 90 96 102 108 114 120 132 t-------------------------------------------------------------------- 1: JOB GLACIER NW - STORMWATER DESIGN 2: REM --- 100 YEAR STORM EVENT FOR DETENTION SIZING 3: 4: TOT 6.15 Total rainfall : 6.15 Inches 5: FIL C:\HYE\ZA.INC ------START OF SUS -FILE ------ 1: C:\HYDRA\CMD\ HYDRA Version 5.85 j.w.morriesette & associates Page 2 =aaaaa�==c==c===a==a=aaaaacvca=cvcamcmaaa===vaaaaaaaa=ave==vvaa=a=v=vv==cveaaa C:\HYDRA\CMD\GL,A100.CMD 10:01 22 -Mar -104 GLACIER NW - STORMWATER DESIGN 2: HYE 10 0.004 0.004 0.004 0.004 0.004 0.004 0.004 0.004 0.004 0.004 0. 005 + 3:0.005 0.005 0.005 0.005 0.005 0.006 0.006 0.006 0.006 0.006 0. 0.007 + 4: 0.007 0.007 0.007 0.007 0.007 0.0082 0.0082 0.0082 0.0082 0.00 82 0.0082 0.0095 + 5: 0.0095 0.0095 0.0095 0.0095 0.0095 0.0134 0.0134 0.0134 0.0180 0.0180 0.034 0.054 + 6: 0.027 0.018 0.0134 0.0134 0.0134 0.0088 0.0088 0.0088 0.0088 0 .0088 0.0088 0.0088 + 7: 0.0088 0.0088 0.0088 0.0088 0.0088 0.0072 0.0072 0.0072 0.0072 0.0072 0.0072 0.0072 + 8: 0.0072 0.0072 0.0072 0.0072 0.0072 0.0057 0.0057 0.0057 0.0057 0.0057 0.0057 0.0057 + 9: 0.0057 0.0057 0.0057 0.0057 0.0057 0.0050 0.0050 0.0050 0.0050 0.0050 0.0050 0.0050 + 10: 0.0050 0.0050 0.0050 0.0050 0.0050 0.0040 0.0040 0.0040 0.0040 0.0040 0.0040 0.0040 + 11: 0.0040 0.0040 0.0040 0.0040 0.0040 0.0040 0.0040 0.0040 0.0040 0.0040 0.0040 0.0040 + 12: 0.0040 0.0040 0.0040 0.0040 0.0040 0.0040 0.0040 0.0040 0.0040 0.0040 0.0040 0.0040 + 13: 0.0040 0.0040 0.0040 0.0040 0.0040 0.0040 0.0040 0.0040 0.0040 0.0040 0.0040 0.0040 + 0.0040Step time 10.00 Minutes Total in original hyetograph 0.17 Inches Adjusting hyetograph from 10.00 minutes to 60.00 minutes Total volume rain in production hyetograph 6..15 Inches Maximum intensity 1.01 Inches/Hr working hyetograph in INCHES/HOUR: 0.00 0.50 1.00 1.50 2.00 Time In/Hr+---------+---------+---------+---------+ 60 0.15 120 0.16 I=== 180 0.20 240 0.23 I===== I I 300 0.27 360 0.32 I==aa=a I I I 420 0.40 480 1.01 I==aaa===alga=floc==.c 540 0.47 1=========1 I I I 600 0.32 660 0.31 I====== l 720 0.27 I=a=== 780 0.25 1===== I 1 1 I 840 0.21 900 0.20 I==== 960 0.18 la=== I I 1020 0.17 1080 0.15 1140 0.15 1200 0.15 I=== I 1260 0.15 I=== 1320 0.15 I=== I I I C:\HYDRA\CMD\ HYDRA Version 5.85 j.w.morrissette & associates Page 3 C:\HYDRA\CMD\GLA100.0 D 10:01 22 -Mar -104 GLACIER NW - STORMWATER DESIGN 1380 0.15 I___ I I 1 1440 0.15.=== 1500 0.00 1 t ---------+----------r---------+---------+ 15: RET ------ END OF SUB -FILE ------ 6: NEW PARKING LOT STORMWATER TO SIOFILTER 7: 8: CHD 6, 0.3, 0.03, 3, 2, 3, 1.0, 0, 0, 0, 0 9: SCS 5, 0.83, 98, 85, 20, .01, 220 Land segment : 5.000 Acres Portion impervious : 0.830 Curve number (CN) for Impervious : 98.000 Curve number (CN) for Pervious : 85.000 K Factor : 20.000 slope of land : 0.0100 Sheet flow distance : 220.000 Feet Computed concentration time : 1.83 Minutes Total Time of Concentration : 1.83 Minutes Total rainfall falling on impervious 92646.67 CuFt Impervious runoff 89159.80 CuFt Portion off impervious 96.24 t Peak CFS rainfall falling on impervious 4.23 CuFt/Sec Peak CFS runoff from impervious 4.06 CuFt/Sec Equivalant "C" off impervious 0.96 Total rainfall falling on pervious : 18975.82 CuFt Pervious runoff : 13730.60 CuFt Portion off pervious : 72.36 Peak CFS rainfall falling on pervious 0.87 CuFt/Sec Peak CFS runoff from pervious 0.64 CuFt/Sec Equivalant "C" off pervious ; 0.73 Total rainfall falling on segment : 111622.50 CuFt Total segment runoff : 102890.40 CuFt Portion off segment : 92.18 Peak CFS rainfall falling on segment 5.10 CuFt/Sec Peak CFS runoff from segment 4.70 CuFt/Sec Equivalant "C" off segment 0.92 C:\HYDRA\CND\ HYDRA, Version 5.85 j.w.morriseette & associates Page 4 C:\HYDRA\CwD\GLA100.CMD 10:01 22 -Mar -104 GLACIER NW - STORMWATER DESIGN Hydrograph off land segment : I - Impervious runoff in CFS P - Pervious runoff in CFS T - Total runoff in CFS 0.00 1.25 2.50 3.75 5.00 Time+ ---------+---------+---------+---------t 0 0.14 0.00 0.14 [ [ [ I [ 60 0.47 0.00 0.47 120 0.71 0.01 0.72 180 0.90 0.05 0.95 IT 240 1.09 0.09 1.19 * [ [ [ [ 300 1.29 0.14 1.44 [ IT [ [ [ 360 1.63 0.22 1.85 IP [ I T I [ [ 420 4.06 0.64 4.70 I P I I II T 480 2.19 0.37 2.57 [ P I I T [ 540 1.17 0.21 1.38 IP I T I [ 600 1.44 0.26 1.70 IP II T I [ 660 0.97 0.18 1.15 I IT I [ [ 720 1.16 0.21 1.37 IP I T I [ [ 780 0.77 0.15 0.92 I IT I I [ 840 0.94 0.17 1.11 I IT [ [ [ 900 0.69 0.13 0.82 I IT [ [ [ [ 960 0.79 0.15 0.94 I 1 T I [ 1020 0.56 0.11 0.67 IT I I [ 1080 0.67 0.13 0.80 I IT I [ 1140 0.57 0.11 0.68 [ * I [ I 1200 0.66 0.12 0.78 ' IT I I I 1260 0.58 0.11 0.69 IT 1320 0.65 0.12 0.77 I IT [ 1380 0.59 0.12 0.70 I IT I I I [ 1440 0.06 0.01 0.07 I I I [ [ Time+---------+---------+---------+---------+ 0.00 1.25 2.50 3.75 5.00 10: CHA 50, 327, 323, 326, 323 Length 50.00 Feet GrUp 327.00 Feet GrDn 323.00 Feet InvUp 326.00 Feet InvDn 323.00 Feet NOTE: Gutter Hydrograph added to Storm Hydrograph. Link number : 1 NOTE: Adjusting hydrographs for worst case situation ®Adding Sto into Event @Adding Diurnal into Design @Adding Event into Design Average Design Flow 0.00 CuFt/Sec Storm flow (no SF) 4.699 Cuft/Sec Design flow including SF 4.699 Cuft/Sec Combined SF : 1.000 CHD Maximum velocity 6.0000 FPS CHD Minimum velocity 0.3000 FPS CHI] Mannings "n" 0.0300 C:\HYDRA'\0M\ HYDRA Version 5.B5 j.w.morrissette & associates Page 5 aaaaaca-- __-_---=accccccaa=acccceaaaaaaGa====aaaa======ac�aa= C:\HYDRA\CMD\GLAl00.CMD 10:01 22 -Mar -104 GLACIER NW - STORMWATER DESIGN CHD Left side slope : CHD Bottom width CHD Right side slope CHD Minimum freeboard CHD Exfiltration : Channel Slope Design flow Depth of flow Velocity : Travel time Width of surface Downstream hydrograph in CFS (Initial time=0.18 min): 0.0000 1.2500 2.5000 3.7500 5.0000 Timef---------+---------+---------+---------+ 0 0.1447 60 0.4678 1=== 1 120 0.7201 180 240 300 360 420 480 540 600 660 720 780 840 900 960 1020 1080 1140 1200 1260 1320 1380 1440 Time 0.9496 1.1868 1.4362 1.8462 4.6988 2.5668 1.3775 1.7003 1.1486 1.3734 0.9201 1.1114 0.8234 0.9417 0.6654 0.7955 0.6812 0.7831 0.6936 0.7735 0.7034 ccaaa== 1 =aacccca caaac===aa la__==aa==Icaaa==aaala=aaa==== 1cc=caa===laaaccaaac= 1=aa=cccaaa f laaacsaa= I I I cc: aa= I 1 1=as===== I f la = I I I==caa i I 1 f==a== I 1 laaccxaa 0.0716 1 11 1 1 +---------+---------+---------+---------+ 0.0000 1.2500 2.5000 3.7500 5.0000 11: 12: RED (0/1.7, 7360/1.7) 1 0.000 1.700 2 7360.000 1.700 13: RES 323, 323, 327, OVER 3.0000 2.00 Feet 3.0000 1.0000 Feet 0.0000 IPH 0.0600 4.70 Cuft/Sec 3.98 Inches 0.33 Feet 4.73 Ft/Sec 0.18 Minutes 3.99 Feet Number of points on Volume/Discharge curve : 2 Maximum capacity of reservoir : INFINITE C:\HYDRA\CMD\ HYDRA Version 5.85 j.w.morrissette & associates Page 6 C:\HYDRA\CND\CLA100.CMD 10:01 22 -Mar -104 GLACIER NW - STORMWATER DESIGN Inlet elevation : 323.00 Feet Outlet elevation : 323.00 Feet Link number : 2 NOTE: Adjusting hydrographs for worst case situation @Adding Sto into Event @Adding Diurnal into Design @Adding Event into Design Average Design Flow : 0.00 CuFt/Sec Storm flow (no SF) : 4.699 Cuft/Sec Design flow including SF 4.699 Cuft/Sec Combined SF 1.000 Diversion hydrographs : I - Incoming hydrograph in CFS X - Exit hydrograph in CFS V - Volume of Reservoir in CuFt divided by10000 0.00 1.25 2.50 3.75 5.00 Time +---------+---------+---------+---------+ 0 0.15 0.15 0.00 I I I 60 0.46 0.46 0.00 I I I I I 120 0.72 0.72 0.00 I I I I 180 0.96 0.96 0.00 I I I I 240 1.18 1.18 0.00 I I I I 300 1.44 1.44 0.00 I * I I 360 1.B4 1.70 0.05 I I XI 420 4.70 1.70 1.13 I V I X I I I 480 2.56 1.70 1.44 I IV X II 540 1.38 1..70 1.33 I * X I I 600 1.70 1.70 1.32 I V * I I 660 1.14 1.70 1.1.2 I 1 X I I I 720 1.38 1.70 1.01 I V I X I I I 780 0.92 1.70 0.73 I VI I X I I I 840 1.11 1.70 0.52 I V I I X I I I 900 0.83 1.70 0.20 IV I I X I 960 0.94 1.50 0.00 I I IX I I 1020 0.66 0.66 0.00 I I I 1080 0.79 0.79 0.00 I * I I I I 1140 0.68 0.68 0.00 I I I I I 1200 0.77 0.77 0.00 1260 0.70 0.70 0.00 I I I I I 1320 0.77 0.77 0.00 I I I I I 1380 0.70 0.70 0.00 I I I I 1440 0.07 0.07 0.00 I I Time +---------+---------+---------+---------+ 0.00 1.25 2.50 3.75 5.00 14: 15: END C:\HYDRA\CMD\ HYDRA Version 5.85 j.w.morrissette & associates Page 7 C\HYDRA\CMD\CLA100.CMD 10:01 22 -Mar -104 GLACIER NW - STORMWATER DESIGN ------ S U M M A R Y O F A N A L Y S I S ------ Run number on command file Number of links Number of hydrographs Total sanitary population Total sanitary area Total storm area Number of pumps Number of reservoirs Number of diversion structures Number of inlets Length of new pipe Length of existing pipe Length of channel Length of gutter Length of transport units Length of pressure pipe Closing DBF and NDX Files 5 3 40 0 0.00 Acres 5.00 Acres 0 1 0 0 0.00 Feet 0.00 Feet 50.00 Feet 0.00 Feet 0.00 Feet 0.00 Feet APPENDIX C Thurston Region Stormwater Facilities Summary 0 6 THURSTON REGION FACILITY SUMMARY FORM PROPONENT'S FACILITY IDENTIFIER: GIacier NW NAME OF ROAD TO ACCESS FACILITY: 705 Rhoton Road SE HEARINGS EXAMINER CASE NUMBER: DEVELOPMENT REVIEW PROJECT NO.: BUILDING SITE APPLICATION NO.: PARCEL NUMBER(S) 22719240100 To be completed by Utility Staff Utility Facility Number: Project Number: Parcel Number Status: Basin & Subbasin: Responsiblc Jurisdiction: PART 1 - Project Name & Proponent Project Name: Glacier NW Project Manager: Tom Hanson Project Contact: Tom Hanson Address: P.O. Box 1730, Seattle, WA 98111 Telephone: (206) 768-7612 Project Proponent: Tom Hanson Glacier NW Facility Summary Form JWM&A # 04112 1 Address: P.O. Box 1730, Seattle, WA 98111 Telephone: (206) 768-7612 Project Engineer: Robert E. Tauscher, P.E. Firm: J.W. Morrissette & Associates Inc., P.S. Telephone: (360) 352-9456 Fact: (360) 352-9990 PART 2 - Project Location Section: 19 Township: 17N Range: 2E PART 3 - Type of Permit Application Type of Permit: Construction Review Other Permits: Grading Other: Other Agencies that have had or will review this Drainage & Erosion Control Plan: None PART 4 - Proposed Project Description What stream basin is this project within: Zoning: Industrial Onsite: Industrial Number of Lots: 1 Yelm Creek (See Appendix C) Glacier NW 2 Facility Summary Form JWM&A # 04112 Avg. Lot Size: NIA Building Permit/Cornmercial Plat: Building Footprint (Acres): 0.16 Concrete Paving (Acres): 3.99 Gravel Surface (Acres): 0 Lattice Block Paving (Acres): 0 Public Roads (incl. gravel shoulder) (Acres): 0 Private Roads (incl. gravel shoulder) (Acres): 3.99 Onsite Impervious Surface Total (Acres): 4.15 PART 5 - Pre -Developed Project Site Characteristics Stream Through Site N Steep Slopes (> 10%) N Erosion Hazard N 100 -Year Flood Plain N Wetlands N Seeps/Springs N High Groundwater Table N Aquifer Sensitive Area N Other: Glacier NW 3 Facility Summary Form JWM&A # 04112 PART 6 - Facility Description Total Area Tributary to Facility Including Offsite (Acres): Total Onsite Area Tributary to Facility (Acres): Design Impervious Area Tributary to Facility (Acres): Design Landscaped Area Tributary to Facility (Acres): Design Total Tributary Area to Facility (Acres): Indicate Types of Facilities Included in Project: Wet Pond Detention 0 Dry Pond Detention 0 Underground Detention: 0 Infiltration Pond: 1 Dry Well Infiltration: 0 Coalescing Plate Separator: 0 Centrifuge Separator: 0 Other: 0 Indicate Outlet Types Included In Project: Filter: 0 Oil/Water Separator: 0 Single Orifice: 0 Multiple Orifice: 0 Weir: 0 Spillway: 0 Pump(s) : 0 Glacier NW Facility Summary Form ]WM&A # 04112 5.00 5.00 4.15 0.85 5.00 4 Other: PART 7 - Release to Groundwater Design Percolation Rate to Groundwater: 20.0 in/hr over pond bottom. PART 8 - Release To Surface Water All stormwater from this site is infiltrated on site with no release to any surface waters. Glacier NW Facility Summary Form JWM&A # 04112 APPENDIX D Basin Map VA 0 P _ ■ i i --------------4--- , .�_�---------- ----_------------ it : ,y• • r•`•3 �4 A. J' �" -' `' r� ■ i i --------------4--- , .�_�---------- ----_------------