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HomeMy WebLinkAboutStormwater Report - PLN General - 7/21/2009 Mason County Stormwater Checklist County Project# Project Name .AMA 4Lg& p;.r- Twnsp,Sec,Range 2-, z -3 a.7 Minimum Requirements of 1992 Stormwater Manual The stormwater checklist identifies the minimum requirements of the 1992 Stormwater Manual. The checklist is intended to identify the locations within the plan that addresses the minimum requirements. Mason County will not perform a technical evaluation of the submittal. Rather,the checklist provides a guide to allow Mason County to review the submittal and determine if the applicant has addressed the minimum features that make up a stormwater plan. It is incumbent upon the applicant and his/her engineer to fulfill all the applicable requirements of the 1992 Stormwater Plan as it relates to the proposed project. Review by Mason County is intended to determine if the plan has addressed the minimum requirements and should not be considered a review for technical accuracy of the plan. During construction of the project,the stormwater plan engineer of record or his/her authorized representative shall inspect the site to ensure the stormwater plan is being implemented as designed. Upon completion of the project, the engineer or his authorized representative shall be required to certify that the stormwater plan has been implemented as designed. Failure to meet the minimum requirements could result in delay or rejection of the application until the deficiencies are corrected. Rft Erosion and Sediment Control.All new development and redevelopment that includes land disturbing activities of one acre or greater shall comply with erosion and sediment control requirements 1 through 14, below. Compliance with the Erosion and Sediment Control Requirements shall be demonstrated through implementation of a large parcel erosion and sediment control plan. All new development and redevelopment that includes land disturbing activities of less than one acre shall comply with the small parcel minimum requirements found in Section 14.48.130, Compliance with the small parcel requirements shall be demonstrated through implementation of a small parcel erosion and sediment control plan. Erosion and Sediment Control Requirement#1: Stabilization and Sediment Trapping. See page/paragraph _ -- J Erosion and Sediment Control Requirement#2: Delineate Clearing and Easement Limits. See page/paragraph Pi z 7 ,; ; Erosion and Sediment Control Requirement#3: Protection of Adjacent Properties. See page/paragraph P �� % �' ► ED � SEP 1 6 426 W: CEDAR STj J Erosion and Sediment Control Requirement#4: Timing and Stabilization of Sediment Trapping Measures. See page/paragraph Erosion and Sediment Control Requirement#5: Cut and Fill Slopes. See page/paragraph �7 '4,_ Erosion and Sediment Control Requirement#6: Controlling Off-Site Erosion. See page/paragraph Erosion and Sediment Control Requirement#7: Stabilization of Temporary Conveyance Channels and Outle s. See page/paragraph je �,,,�, Erosion and Sedi nt Control Requirement#8: Storm Drain Inlet Protection. See page/paragraph f'�� j& 0 Erosion and Sedi nt Control Requirement#9: Underground Utility Construction. See page/paragraph a ie) 3 y S— Erosion and Sedim�ent Control Requirement#10: Construction Access Routes. See page/paragraph -f-u6;,c,.. Erosion and Sediment Control Requirement#11: Removal of Temporary BMPs. See page/paragraph -7-1",1_ jJ " 12 Erosion and Sediment Control Requirement#12: Dewatering Construction Sites. See page/paragraph Erosion and Sediment Control Requirement#13: Control of Pollutants Other than Sediment on Construction Sites. See page/paragraph Erosion and Sedi nt Control Req * ement#14: Maintenance. See page/paragraph // Erosion and Sediment Control Requirement#15: Financial Liability. See page/paragraph ., #2: Preservation of Natural Drainage Systems. Natural drainage patterns shall be maintained, and discharges from the site shall occur at the natural location to the maximum extent practicable. See page/paragraph i3 �G�c ,•u, _ .� _ Q/#3: Source Control of Pollution. Source control BMPs shall be applied to all projects to the maximum extent practicable. Source control BMPs shall be selected, designed, and maintained according to an approved m nual. See age/paragraph !tJA mil— #4: Runoff Treatment BMPs. All projects shall provide treatment of stormwater. Treatment BMPs shall be sized to capture and treat the water quality storm, defined as the six-month, twenty-four hour storm. The first priority for treatment of stormwater shall be to infiltrate as much as possible of the water quality design storm into the ground. Pretreatment of stormwater prior to infiltration into the ground may be required. See page/paragraph ©#5: Streambank Erosion Control.The requirement below applies only to situations where stormwater runoff is discharged directly or indirectly to a stream, and must be met in addition to meeting the requirements in m711/e, um requirement#4, Runoff Treatment BMP's. See page/paragraph ry e e#6: Wetlands. Stormwater discharges to wetlands shall maintain the wetland's natural hydroperiod and flows to the extent needed to preserve or enhance its existing functions and values. Prior to proposing discharge of higher volumes of stormwater to a wetland, alternative discharge, detention, and infiltration practices located in areas outside the wetland shall be evaluated and employed by the roject engineer where feasible and practicable. See page/paragraph ,� Z'47: Water Qualitv Sensitive Areas.Where the Mason County commissioners or their designee determine that the minimum requirements do not provide adequate protection of water quality sensitive areas, either on-site or within the basin, more stringent controls shall be required to protect water quality. An adopted and implemented basin plan (minimum requirement#9) may be used to develop requirements for water quality sensitive areas that are tailored to a specific basin. See page/paragraph �,� #8: Off-Site Analysis and Mitigation. Downstream Analysis May Trigger Additional Requirements. The project engineer shall provide a detailed qualitative analysis of the flow path of the discharge from the project site to the receiving water. This requirement shall apply to all projects where a drainage and erosion control plan is prepared, including those proposing retention facilities. This analysis shall include flow routing, and provide existing pipe and channel sizes and estimated capacities. In addition, the project engineer shall discuss any known or expected downstream erosion, flooding, or water quality problems, including those that may be caused by interflow from the proposed retention facility. The director or designee shall have the discretion to specify the distance and level of detail to be provided by the project engineer. In making this determination, the director or designee shall consider such factors as the relative size of the new development, availability of other hydrologic work for the drainage area, and the extent to which stormwater generate on the project site is to be infiltrated. See page/paragraph E?#8: Basin Planning. Basin plan supersedes Manual See page/paragraph , 12.1 21#10: Operation and Maintenance. An operation and maintenance schedule shall be provided for all proposed stormwater facilities and BMPs, and the party(or parties) responsible for maintenance and operation shall be identified. An operation and maintenance (O&M)covenant will be required to cover all privately owned and maintained stormwater facilities approved by the director. O&M Covenant forms are available at the Mason County public works office. A copy of the completed instrument shall be recorded with the county auditors' office by the proponent and a copy of the recorded instrument is required to be submitted to the public works department prior to final approval of the completed permanent stormwater facilities. See age/paragraph p �- L b Q#11: Financial Liability. Performance bonding, or other appropriate instruments shall be required for all projects to ensure compliance with these standards. See page/paragraph I certify that the stormwater plan submitted for this project fulfills the applicable provisions of the 1992 Stormwater Manual. Engineer Date Applicant Date 4 r ITEMS TO CONSIDER WHEN COMPLETING THE CHECKLIST PIs your project in either the Allyn and Belfair UGA? If so, needs to meet the 2005 Stormwater Manual. ('tiF• P Does the drainage affect WSDOT Ditches. If Yes,contact must be made with Jr WSDOT. tv;11 ©Runoff that satisfies 1992 Manual requirements does not necessarily meet WSDOT standards for runoff into their ditchlines runoff affecting County or private ditches? Needs to be addressed. [''What are the impacts downstream? Are they addressed.( % s [J-Iqas water quality and quantity BMP's been provided as required? �n�• J�rffis provision been made to resize culverts if required? El-lave you provided calculations for basin(s)conveying to point of compliance? (lye-5- ?'Have you provided calculations for Stormwater features: pond sizing,conveyance systems, etc. �B []`Does Geological Assessment/Report address stormwater features placed near slopes? 119'Do we need to recommend more BMP's C%✓,# ['Does your proposal disrupt natural drainage systems and if so what is the mitigation? ' � Is the designer's PE Stamp and signature provided on calculations and drawings? y4 5 Mason CountyStor mwater Report for PROJECT: HAMA HAMA PIT CLIENT: HAMA HAMA COMPANY PO Box 250 Lilliwaup, WA 98555 Mason County July 21, 2009 4 1!, O U z J a3;4 N AI AIL d J�/v$ •4 YV Z, ocP� s 12-02 -09 =D ENGINEERING, LLC PO Box 25422 ederal Way, WA 98093-2422 Ph(206)501-5708 TABLE OF CONTENTS TABLEOF CONTENTS .............................................................................................................2 1. PROJECT LOCATION AND DESCRIPTION................................ 2. GENERAL SOILS DESCRIPTION and INFILTRATION RATE............................................ 5 3. Erosion Control Requirements (Minimum Requirement#1)..................................................... 7 A. Stabilization and Sediment Trapping................................................................................. 7 B. Delineate Clearing and Easement Limits........................................................................... 7 C. Protection of Adjacent Property......................................................................................... 8 D. Timing and Stabilization of Sediment Trapping Measures ............................................... 8 E. Cut and Fill Slopes............................................................................................................. 9 F. Controlling Off-Site Erosion.............................................................................................. 9 G. Stabilization of Temporary Conveyance Channels and Outlets...................................... 10 H. Storm Drain Inlet Protection........................................................................................... 10 I. Underground Utility Construction.................................................................................... 10 K. Removal of Temporary BMPs......................................................................................... 11 L. Dewatering Construction Sites.......................................... . M. Control of Pollutants Other Than Sediment on Construction Sites................................. 11 N. Maintenance..................................................................................................................... 11 4. Preservation of Natural Drainage Systems (Minimum Requirement#2)................................. 13 5. Source Control of Pollution (Minimum Requirement #3)........................................................ 14 6. Runoff Treatment BMPs(Minimum Requirement#4) ............................................................ 15 7. Streambank Erosion Control (Minimum Requirement#5) ...................................................... 16 8. Wetlands (Minimum Requirement#6)..................................................................................... 17 9. Water Quality Sensitive Areas(Minimum Requirement#7) ................................................... 18 10. Offsite Analysis and Mitigation(Minimum Requirement#8) ............................................... 19 11. Basin Planning(Minimum Requirement#9)..........................................................................21 12. Operation and Maintenance (Minimum Requirement#10)....................................................22 13. Financial Liability (Minimum Requirement#11)................................................................... 24 APPENDIX 14. Basin Areas, Calculations, and Supporting Data 15. Maps (Including Vicinity Map, Existing site conditions, Proposed Mining Sequence and Proposed Pond Plan) 1. PROJECT LOCATION AND DESCRIPTION The Hama Hama Pit Project (Parcel #324270004000) is located along Highway 101 just south of Eldon, Washington, in Mason County. The pit and entrance is located on the west side of Highway-101 at approximately mile marker 320 immediately south of the Hama Hama River. To the east is the Hood Canal. This project proposes to mine gravel on the approximately 300-feet mound that has been designed as long term commercial forest land (LTCF) zoning. This project includes submittal for a conditional use permit (CUP) that will allow gravel mining in the parcel and revert the land usage back to forested/vegetated upon completion of mining activities in 50 years. Forestry clearing associated with the phased mining will not be mass cleared, but will have small areas cleared gradually. It is anticipated that approximately five acres to 43 acres will be open at any given period with the remaining lands to stay in it's natural state. Typically the open lands needed to mine gravels will be less than 10 acres. The permanent pond proposed in this report assumes that the `permanent' pond will be used with a 43 acre open mining area that progresses with each mining sequence. (See mining sequence figure developed by Garrison Resource Group (GRG) in the appendix for the progression) The mining sequence shall progress from M- 1 (located closest to the northern portion of the project site) to M-5 (located closest to the southern portion of the site). The following stormwater report provides the storm-water treatment for permanent and temporary stormwater control associated with the Hama Hama Pit Project. All minimum Mason County stormwater requirements are sectioned off within this report. Descriptions for this project is provided and required on clearing of over one acre. This project's clearing will be greater than one acre. Compliance with the Mason County Erosion Control Requirements #1 to #14 (also called Minimum Requirement #1) are provided with implementation of the Large Parcel Erosion and Sediment Control Plan (TESC Plan). In addition, Minimum Requirements #2 to #11 (or more commonly called the Permanent Stormwater Quality Control Plan) is provided with this stormwater report and stormwater plan. A future topsoil stockpile plan is also provided by Garrison Resource Group that is located in the Appendix. These stockpiles will have grass covering the mounds during the `storing' period. Grassing the topsoil mounds will minimize potential surface runoff into or out of the project site. 2. GENERAL SOILS DESCRIPTION and INFILTRATION RATE A steep slope geotechnical analysis report is provided by a separate consultant that assesses the slope hazards associated with mining the gravel mound next to Highway 101. The proposed project location in Mason County was reviewed using the National Cooperative Soil Survey (via the US Department of Agriculture) in determining the soils on-site. In addition, an infiltration testing analysis was conducted on the consistently sandy gravelly soils by HWA Geoscience, Inc. and is provided within the Appendix. Three pit tests (one deep pit and two hand augured shall four feet bores) were conducted by PELLC to ensure sols were consistent in the infiltration pond areas proposed. They were found to be consistent via testing, field observations, and from the opened faced wall as seen from Highway 101. Soils found on-site were generally found to be Gn, Gb, and Hf as designated by the United States Department of Agriculture NRCS naming convention. Along Highway 101 the Ma designation is most prevalent. (See Figure xx for approximate soil types and it's areas). Gn : Grove gravelly sandy loam with 30 to 45 percent slopes Gb: Grove cobbly sandy loam with 0 to 5 percent slopes Hf. Hoodsport gravelly sandy loam, 30 to 45 percent slopes Ma: Made land Tn: Tidal marsh with 0 to 2 percent slopes The Gn and Gb soils consist of more than 95% of the project site soils and is the primary soil type mined from the site. PELLC conducted one deep excavated 12.5 feet pit test at the base of the gravel slope in the Gn soil area. This soil pit test was conducted on May 15`h at 1:35 pm in the afternoon. Conditions were sunny and clear skies with temperature in the low 60s. Prior to the soil pit test there appeared to be a couple of significant rain events at the project area. Evidence of a recent rainfall event (May 13t' and 14t') correlated with some very small localized surface ponding from the rain events. From the soil pit test to a depth of 12.5 feet, cobbles with sandy loam were observed for the entire depth of the pit. The sandy loam was a light, brownish color with some fines to mostly medium sand for the sample's smaller diameter soils. Groundwater was not evident during the pit test excavation nor was there any fine grained lens soil layers in the profile. The soils found on-site is consistent with the glacial outwash type that would be predicted with drainage considered to be excessively drained. The capacity of Gn and Gb soils will provide pp water permeability rate of approximately 2.0 to 6.0 inch/hr for the most limiting layers to transmit water. For purposes of infiltration ponds and ditches to be used in this project, 3.87 x 1 OE-3 cm/sec (or 5.36 inches/hr) will be used to assist with lacility sizing. A custom soils resource report is provided within the Appendix for the subject area. 3. Erosion Control Requirements (Minimum Requirement #1) A. Stabilization and Sediment Trapping During temporarily exposed land use conditions needed during open mining,all soils will be stabilized by application of the WA Department of Ecology's BMPs. These BMPs include use of sediment ponds, infiltration ditches, cut-off ditches, rock or mulch check dams in ditches (when needed), mulching, vegetation growth, and vegetated strips. From October 1 to April 30, no soils that drain offsite of he project area whatsoever will remain un-stabilized for more than 2 days. These open source soils that do drain off the site shall at minimum be mulched and seeded as well as pass through a sediment pond if stormwater runoff offsite is evident. The proposed temporary sediment pond shall have the following physical characteristics for each open five areas that may drain offsite: Sediment Trap Dimensions at base of pond: Length=40 feet Wid th=20 feet Sideslopes =3:1 Due to the small size of the sediment trap, no access to the bottom of the structure is required. Cleaning may be done via an excavator on the 3:1 sideslopes. B. Delineate Clearing and Easement Limits Easement limits and clearing limits are provided in a map shown in the Appendix. Clearing will be done in stages as shown in the GRG mining sequence figure via M-1 to M-5. The total progression period will be for 50 years with reclamation, respreading of topsoil, and replanting to be done at the end of the mining period. Clearing will progress first along the northeastern portion of the property near the existing pit entrance. In the field, clearing limits and setbacks, sensitive areas, buffers, etc will be marked prior to clearing any natural areas. C. Protection of Adjacent Property Adjacent properties will be protected from sedimentation with use of a well vegetated buffer strip when possible. The ultimate western and southern boundaries of the proposed project mining site wi11 always have vegetated buffers. The northern site will also have vegetated buffers to protect the existing wetland to the north. A wetland buffer is shown in the figures provided by GRG and contained in the Appendix. Most of the bordering slopes adjacent to Highway 101 will be preserved in it's existing condition so a vegetated buffer strip will be retained. When this vegetated buffer strip is ineffective against preventing sediment from moving to adjacent properties, which is highly doubtful, then perimeter ditches (v-type ditches), swales(ditches with flat bottoms) with rock dams, sediment traps, infiltration trenches, and sediment ponds will be utilized. Most adjacent properties will not be affected by sediment due to the lack of proposed mining along the property boundaries. D. Timinga Stabilization and ization of Sediment Trapping Measures The stabilization of sediment trapping measures will occur before major clearing or other land disturbing activities occur. The sediment traps and ponds are designed to treat stormwater. Sediment ponds will be in place prior to grading with these temporary sediment ponds or traps moving along with mining sequencing when needed. It is anticipated that the natural gravels and soils on site will infiltrate most runoff from the site directly into the ground without the need for any facilities. This report proposes DOE BMPs in the unlikely event that the naturally opened mining areas do not infiltrate runoff quickly. For example, if a 25 year recurrence storm occurs in the project area, then the temporary facility will aid with infiltration of the runoff as a secondary alternative if the outer fringes of project area is not incised within the pit area. Most runoff from the site will remain on-site due to proposed in- sized infiltration facilities, but if any runoff does travel offsite then additional traps and ponds will be built prior to discharge offsite. Prior to winter wet weather months by end of September, areas where stockpiles are located will be mulched, hydroseeded, and/or covered. Covering, seeding, mulching, etc. will prevent stockpiles from generating uncontrollable sediment laden runoff. E. Cut and Fill Slopes Slope runoff produced from cut or fill areas will be designed in accordance with the 1992 DOE Stormwater Manual. This project proposes to be mined in phases with road slopes draining towards the ditch. Ditches will most likely absorb any road runoff and infiltrate into the ground. The existing logging road is built in this manner that accesses to the top of the hillside and slopes towards the upslope side. There is no evidence of erosion in the ditches or large amounts of sheet flow. If long, steep slopes are proposed, then the following will be implanted to prevent drainage from coming off the slopes: 1. Roughen the slope with tracks perpendicular to flowpaths. 2. Ditch interceptors will be used at the top of slopes to prevent runoff from entering the slope. 3. Concentrated stormwater will not be draining down the slopes. They will be conveyed via infiltration ditches and most likely will infiltrate into the subsurface. 4. Drainage will be provided when instances of a water seepage is occurring on the slope. It is anticipated that the project will have mostly cut slopes and cut areas that will be stockpiled. All stockpile locations will not generate runoff offsite since the gravel pit will be mostly in-sized. It is anticipated that open and cut areas will not be greater than 5.0 acres at any given time. Each mining segment shall progress as shown in the Mining Sequence Figure provided. F. Controlling Off-Site Erosion Erosion will be kept out of off-site areas as much as possible given increased runoff, volume, peak flow and velocities resulting from the clearing of the forested upslope properties. Keeping runoff out of offsite areas will be require utilization of infiltration trenches, ditches, infiltration ponds,etc. In addition, silt fences may need to be utilized as well as vegetated buffers. G. Stabilization of Temporary Conveyance Channels and Outlets Temporary conveyance channels shall be sized with a minimum flow conveyance of the 2 years, 24 hour frequency event for developed landuse conditions upstream. Since the gravel mine will be constructed and used as needed, the ultimate upstream channel conveyance is designed within this drainage plan. Stabilization shall be installed to prevent erosion of outlets, streambanks, slopes, and downstream properties. H. Storm Drain Inlet Protection Storm drain inlets that work during construction will have treatment prior to discharge into the storm drain inlets to prevent clogging of the drain and pipe system. I. Underground Utility Construction Any construction of underground utility lines shall be subject to the following criteria: Where feasible, no more than 500 feet of trench shall be opened at one time. Where consistent with safety and space considerations, excavated material shall be placed on the uphill side of trenches. Trench dewatering devices shall discharge into a sediment trap or sediment pond. The Hama Hama pit project proposes to not open any trenches except during construction of the sediment trap(s) or pond(s). Open trenches will be very limited. No proposed buildings or utilities are needed on-site. Any trench dewatering will be contained in sediment traps or sediment ponds during and after construction. The project does not propose to construct any underground utilities or deep trenches for stormwater purposes. J. Construction Access Routes Paved roads are not needed at this project site since the underlying soils are Gn and Gb type soils that provide a good structural base. Construction access road entrances from Highway 101 will have angular rock placed to prevent sediment from tracking onto the paved road. In addition, paved streets will be swept when needed and at the end of each day. Water trucks will keep dust down during dry months and if dust is being generated from the access roads. K. Removal of Temporary BMPs Temporary BMPs will be removed within 30 days after final site stabilization is achieved or when the BMPs are not needed. Any trapped sediment shall be cleaned out or stabilized within the site. Disturbed soils will be revegetated and permanently stabilized. L. Dewatering Construction Sites Any dewatering devices used will discharge into a sediment trap, baker tanks, sediment pond, or other BMPs that separate out sediment laden runoff. It is not anticipated that any dewatering devices will be used on this project. M. Control of Pollutants Other Than Sediment on Construction Sites All pollutants other than sediment that occur on-site or is handled on-site shall be disposed of in a manner that does not cause contamination to storm-water. These pollutants include, but are not limited to, temporary fueling tanks, chemical storage facilities with hazardous materials, etc. N. Maintenance All temporary and permanent erosion and sediment control BMPs shall be maintained and repaired as needed to assure continued performance of their intended function. Maintenance on infiltration facilities will need to have sediment skimmed off the top layer when runoff is not infiltrating through the facility and is plugged by fines. All maintenance and repair shall be conducted in accordance with the 1992 Department of Ecology's Stormwater Guidance Manual for this project. These temporary and permanent erosion and sediment control BMPs include: • Sediment traps or ponds when larger sub-basins greater than 3.5 acres of contributing areas are present • Infiltration ponds • Infiltration galleries • Infiltration ponds with bioswale i 4. Preservation of Natural Drainage Systems (Minimum Requirement #2) Discharges from the site shall be maintained at all perimeter locations of the project site. Currently there exists a mound of gravel and soil that is proposed to be mined that mostly drains to the NE towards US Highway 101 and ultimately to the Hama Hama River. A small portion of runoff along the northwest portion of the site's slope drains to the depression site to the north of the parcel. This depression runoff drains to the Hama Hama wetland and river. All runoff eventually discharges to the Hama Hama River. (See runoff downstream pathway Figure 3 located in the Appendix for more details.) 5. Source Control of Pollution (Minimum Requirement #3) Source control will be applied to this project using the BMPs approved by the 1992 Department of Ecology Stormwater Guidance Manual, Chapter I-4. There will not be much source pollution from the site besides the possibility of runoff that contains some sediment. There will not be any impervious surfaces placed on the project site except for a small job trailer. In addition, infiltration facilities is optimal given the soil conditions on this site to prevent concentrated runoff from discharging downstream to Highway 101's roadside low elevation. There is no roadside ditch due to the very pervious soils in the area. Therefore use of the following BMPs is suggested: Water quality infiltration basins Water quality infiltration trenches Sand filtration basins Sand filtration trenches Wet ponds or detention ponds are not recommended in this area due to the infiltration capabilities of the on-site soils. This stormwater plan suggests utilizing runoff treatment only since no downstream streambank erosion was observed prior to runoff discharging into the Hama Hama River. Streambank erosion control BMPs are usually needed in urban developments. This project is in a rural area and is very `controllable' via use of runoff treatment infiltration BMPs. In addition, little or no impervious runoff will be generated from the site. Runoff will change from one that is predominantly forested to grass/cleared runoff. Eventhough the forest conditions will be periodically cleared,there will be little or no runoff due to the infiltration capabilities of the soils below the 1.5 feet to 2.0 feet deep topsoil layer. The soils on- site and the lack of erosion from the existing logging roads suggest that runoff drains immediately into the soils. 6. Runoff Treatment BMPs (Minimum Requirement #4) This project will provide treatment of runoff per the minimum requirement#4 stated in the 1992 DOE Stormwater Manual. The 6-month, 24-hour return period storm will be contained and treated from any cleared area using an infiltration pond or trench, after being treated via a constructed bioswale that filtrates . Groundwater will not be affected since it is greater than 12 feet below elevation 20.0 feet as was observed via a pit test conducted by PELLC near the site access location. The project site will grade to approximately elevation 40.0 as shown in the final grading site plan. (See Appendix for calculations associated with the ultimate proposed infiltration facility of the project site.) Note that runoff will neither be discharged to a stream or a wetland from the site, so no Streambank Erosion Control is required on the project site. 7. Streambank Erosion Control (Minimum Requirement #5) The streambank erosion control criteria is not required for this project site since the runoff all drains into the ground and no runoff appears to be draining offsite even after a large storm. No runoff drains directly into a stream from the project site boundaries. All proposed runoff will be treated via infiltration with the majority of runoff to contribute to baseflow conditions. 8. Wetlands (Minim um um Requirement #6) A wetland buffer exists to the north—northeast boundary of the project site. A wetland buffer will be maintained in this area. Vegetation, slope, grading and etc. will be maintained in this 250-feet radius buffer. Since all runoff currently drains into the soil and proposed runoff will also maintain it's existing characteristics of infiltration into the ground, then the wetlands should maintain it's baseflow conditions during and after site activities. 9. Water Quality Sensitive Areas (Minimum Requirement #7) No water quality problems should be expected as a result of this project since all runoff will be infiltrated. In addition, the steep slope area will be evaluated by a professional geotechnical engineer via a separate report for stability and erosion potential. 10. Offsite Analysis and Mitigation (Minimum Requirement #8) The offsite analysis and downstream quarter mile examination was conducted on May 15t' after two back to back short duration, intense rain events that occurred the previous day and night. Therefore any observations of runoff problems would be visible during the '/4 mile downstream analysis. Weather was in the low 60s with precipitation evident due to some roadside low elevation ponding. The northwest, north, and east perimeter of the project site was examined for excessive evidence of erosion, sedimentation, water quality, water quality violations, or spills/discharges. There existed no evidence of any erosion downstream from the project site's slope on the northwest face of the slope. Heavy vegetation was littered throughout the northwestern and western side of the slope and no concentrated ditch runoff was evident. Due to the soils on-site, most or all runoff drains to through the layer of topsoil and into the infiltrative soils on the northwest slope. The eastern slope of the project is mostly untouched forested land cover also. This project site has second growth trees with very good vegetation cover throughout most of the parcel. Runoff from the eastern slope doe not accumulate into a concentrated channel as is evident from the lack of a defined roadside ditch. Soils are somewhat of a different consistency near the roadside and is due to use of fill, structural soils. The north side of the project has a wetland that borders close to the northern boundary. This wetland gets most of it's flow from baseflow and not any defined ditch system draining to the wetland. There existed no evidence of any streambank erosion along this wetland area or any ditches leading to the wetland area. The Hama Hama River is immediately downstream of the wetland and flows under the Highway 101 bridge prior to draining into the Hood Canal. This is the extent of the '/4 mile downstream analysis prior to discharge into the Hood Canal. No evidence of stream erosion, slope erosion, or sediment deposition is evident in this north side area. In general, the proposed project runoff will sheet flow(if any)across the property towards the northeast to the wetland with the ultimate discharge into the Hama Hama River. The runoff from the site is very little to no runoff due to the overabundance of 2"d forested vegetation on-site. In addition, sub-surface conditions with sandy and gravelly soils tends to infiltrated any rains straight into the ground. The wetland to the northeast is a percolating wetland that is mostly made via sub-surface groundwater and seeps. This project should mimic the existing runoff characteristics by discharging 100%of the runoff into infiltration facilities including infiltration trenches and ponds. I i 11. Basin Planning (Minimum Requirement #9) No basin plans exist for this project area in Mason County. 12. Operation and Maintenance (Minimum Requirement #10) The operation and maintenance of the infiltration facilities is vital to the long term success of the project stormwater system. Lack of maintenance will prevent runoff from infiltrating into the soils and potentially cause localized ponding in the project site,backwater, and potentially pollution. The following are brief descriptions of physical facilities proposed on the project site: * Topsoil stockpile areas: Topsoil stockpile areas are at various locations of the excavated areas and are to be used for future reclamation when the project mining activities are completed. These topsoil piles shall be seeded at the minimum during late September to mid October to promote grass cover growth. Prior to seeding, plastic covering shall be installed on any topsoil stockpile areas to prevent runoff from intermixing with topsoil. * Water Quality Infiltration Basin: Soils logs have been conducted at the site of the infiltration basin. The soils are described within the soils section of this report. When infiltration basins are placed into service, monthly inspections shall be conducted to ensure adequate performance of the facility. Inspections can be reduced when the facility is found to be performing adequately after a series of inspections. The access ramps into the infiltration facilit shall be properly maintained to ensure pY P Pe Y ease of future sediment removal. Maintenance of vegetation on the basin floor and side slopes are necessary to promote turf and root growth. Bare spots are to be immediately revegetated and stabilized. The permanent infiltration basin shall be `different' from the temporary sediment trap/pond basin in that the permanent facility shall be free of heavy concentration of fine sediments and fresh construction runoff. There are three main maintenance activities that must be maintained within the infiltration basin that includes vegetation maintenance(when vegetation is used to aide in infiltration), sediment control, and inspection schedule. These three maintenance items must be properly managed to ensure proper operation of the facility. * Water Quality Infiltration Trench• These facilities are to be used alongside narrow and long areas that do not support pond shaped sizes for runoff treatment. Infiltration trenches or ditches can be used for this site since groundwater depth is not evident from the various borings done in the past or by PELLC. These facilities can be useful applications for offline areas hard to treat runoff due to area constraints. Stone aggregates should be placed in 12 inch lifts and compacted using plates. Care must be used when placing stone aggregates with not contaminating the stone with the natural soils. Contaminated stones shall be removed and replaced with uncontaminated aggregates. Use of fabric will aide in keeping stone uncontaminated. i 13. Financial Liability (Minimum Requirement #11) Performance bonding shall be provided for within this project to ensure compliance with the 1992 Department of Ecology Stormwater standards via the strict Department of Natural Resources mining requirements. Financial resources shall be proven to be adequate via the DNR bonding to perform the stormwater management plan requirements. Funds must be available to implement erosion control measures required for the mineral resources DNR permit. 14. Basin Areas, Calculations, and Supporting Data The runoff treatment design using the Santa Barbara Urban Hydrograph methodology is used in the infiltration pond design. The storm to be modeled is the 6 month, 24 hour storm event(or 64%of the 2 year, 24 hour storm event) without the need for a correction factor due to not needing to design for the stream-bank erosion control criteria as discussed in Section 6 and 7. The Washington State Iso-Pluvials for the following storm events are listed below: 2 year, 24 hour precipitation=2.0 inches 100 year, 24 hour precipitation=4.5 inches 100 year, 7 day precipitation = 10.2 inches The following section provides supporting design information for existing and proposed landuse on the project site for each 5 acres that is cleared and open on the project site, as well as the total project build-out. EACH.S ACRE OPENED FOR MINING EXISTING CONDITION CN Forested Area(2"d Growth) = 5.0 acres 72 PROPOSED CONDITION Gravel Area= 5.0 acres 82 Length of Overland Flow= 540 feet (of loose gravel) Slope=25.9% Length of Ditch Flow= 525 feet(of gravel ditch) Slope= 0.95% Proposed 2-year, 24hr Discharge potential = 0.52 cfs TOTAL PROJECT BUILDOUT(50 YEARS): For the full build-out condition, the permit boundary land area will have more than half of the area vegetated with grass and native vegetation upon the slopes and with the bottom area in open grave condition and topsoil stockpiles. EXISTING CONDITION CN Forested Area(2"d Growth)= 179 acres 72 PROPOSED CONDITION Grassed Area(Pasture) = 122 acres 78 Open Gravel Area=43 acres 82 Length of Sloped Overland Flow= 1058 feet(of grassed area), Slope= 26.4% Length of Mild slope Ditch Flow= 1864 feet(of loose gravel), Slope=0.3 % Proposed 2yr, 24hour Potential Flowrate =4.36 cfs Proposed 100yr, 7day Potential Flowrate= 149.87 cfs Infiltration Facility Sizing: Via use of 5.36 inches/hr infiltration rate and converting to minutes per inch to use within Water-Works program,then applying a factor of safety of 2 to determine the infiltration rate,the infiltration rate is 5.6 minutes per inch. For each 5 acres open up and the remaining left in a natural state,the following infiltration water quality facility is needed: * Bio-swale pre-treatment facility * Infiltration discharge facility with minimum 700 cubic feet of volume * Approximate bottom dimensions=40' x 20' with minimum 2.5 feet depth that includes 1.5' of overflow elevation. For water quality storm (64%of the 2 year, 24 hour event) on the ultimate 50 year build-out scenario we assume 43 acres of open gravel area and the remaining areas are covered with grass and native vegetation growth: * Bio-swale pre-treatment facility * Infiltration discharge facility with minimum 52,010 x 0.64 = 33,287 cubic feet of volume * Approximate bottom dimensions= 100' x 70' with 8 feet depth For the ultimate closed depression facility that treats all discharges prior to discharge into groundwater assuming 50 year build-out, 43 acres of open gravel area, and the remaining areas with grass and native vegetation growth: * Bio-swale pre-treatment facility * Infiltration discharge facility with minimum 1,456,541 cubic feet of volume * Approximate bottom dimensions=400' x 300' with 14 feet depth I • ter. t ��r' . v U s STORMWATER MANAGEMENT MANUAL FOR THE PUGET SOUND BASIN Table III-1.3 SCS Western Washington Runoff Curve Numbers (Published by SCS in 1982) Runoff curve numbers for selected agricultural, suburban and urban land use for Type lA rainfall distribution, 24-hour storm duration. LAND USE DESCRIPTION CURVE NUMBERS BY HYDROLOG SOIL GROUP A B C D Cultivated land(1) : winter condition 86 91 94 95 Mountain open areas: low growing brush & grasslands 74 82 89 92 Meadow or pasture: 65 78 85 89 Wood or forest land: undisturbed 42 64 76 81 Wood or forest land: young second growth or brush 55 72 81 86 Orchard: with cover crop81 88 ! 92 94 Open spaces, lawns, parks, golf courses, cemeteries, landscaping.Good condition: grass cover on Z75% of the 68 801 86 90 area Fair condition: grass cover on 50-75% of 77 85 90 92 the area Gravel roads & parking lots: 76 85 89 91 Dirt roads & parkinglots: 72 8 87 89 Impervious surfaces, pavement, roofs etc. 98 98 98 98 Open water bodies: lakes, wetlands, ponds etc. 100 0 100 100 Single family residential(2) : Dwelling Unit/Gross Acre %Impervious(3) Separate curve number 1.0 DU/GA 15 shall be selected for 1.5 DU/GA 20 pervious & impervious 2.0 DU/GA 25 portions of the site 2.5 DU/GA 30 or basin 3.0 DU/GA 34 3.5 DU/GA 38 4.0 DU/GA 42 4.5 DU/GA 46 5.0 DU/GA 48 5.5 DU/GA 50 6.0 DU/GA 52 6.5 DU/GA 54 7.0 DU/GA 56 PUD's, condos, apartments, %impervious commercial businesses & must be industrial areas computed (1) For a more detailed description of agricultural land use curve numbers refer to National Engineering Handbook, Sec. 4, Hydrology, Chapter 9, August 1972. (2) Assumes roof and driveway runoff is directed into street/storm system. (3) The remaining pervious areas (lawn) are considered to be in good condition for these curve numbers. III-1-12 FEBRUARY, 1992 HAMAHAMA-BASIN-SUMMARY.PRN 2/9/00 9:24:15 am page 1 HAMA HAMA GRAVEL PIT JUNE 2009 HYDROLOGICAL CALCULATIONS BASIN RESULT SUMMARY BASIN -----VOLUME---- -RATE- ----TIME----- Hydrograph Area ID ---cf-- AC-ft --cfs- -min- hours Methodology Acres PR2-24A 11655 0.27 0.52 480 8.00 SBUH Method 5.00 PR2-24B 227807 5.23 4.36 960 16.00 SBUH Method 165.00 PR2-24C 4084248 93.76 149.87 540 9.00 SBUH Method 165.00 Page 1 HAMAHAMA-LEVELPOOL.PRN 2/9/00 9:2S:1 am page 1 HAMA HAMA GRAVEL PIT JUNE 2009 HYDROLOGICAL CALCULATIONS asssasssaasxaassxsxazs:sxxsxxxxxaxaxxsssxxxxxxssssaaxxxxxxcxxazcasxxx LEVEL POOL TABLE SUMMARY MATCH INFLOW -STO- -DIS- <-PEAK-> OUTFLOW STORAGE <--------DESCRIPTION---------> (Cfs) (Cfs) --id- --id- <-STAGE> id (Cfs) VOL (cf) sxxsxsaxxsxxxssxxsssxsxxsxxsxssxxsxxxxxxssaassxaxxsxxxx xx s sscssaxxxsssaxxsxscsss 2yr,24hr 5acres . .. .. . ..... ... 0.52 0.52 InfilA Emerl 100.72 11 0.27 677.33 cf 2yr,24hr 169acres . . . .. .... . .. 4.36 4.36 Infi16 Emer2 105.21 12 3.38 52006.68 cf 1yr,7d 169acres ... .. .... ... 149.87 149.87 Infilc Emer3 110.21 13 43.97 33.4376 ac-ft Page 1 HAMAHAMA-STORAGE-DISCH.PRN STAGE <--DISCHARGE---> STAGE <--DISCHARGE---> STAGE <--DISCHARGE---> STAGE <--DISCHARGE---> (ft) ---cfs-- ------- (ft) ---cfs-- ------- (ft) ---cfs-- ------- (ft) ---cfs-- ------- Mxaszmazzssssxssxxxxxxxscxzsxxxsssaxssxxssassamxcsxxasxacrosaxxsxxxaxassxaxxs:szasasasszzaaxxacsax¢xzxx .00 0.0000 111.80 18.569 112.60 6S.867 113.40 145.52 111.10 0.6382 111.90 22.861 112.70 73.96S 113.50 1S7.97 111.20 1.8787 112.00 27.599 112.80 82.577 113.60 171.00 111.30 3.5869 112.10 32.792 112.90 91.712 113.70 184.62 111.40 5.7309 112.20 38.448 113.00 101.38 113.80 198.83 111.50 8.3007 112.30 44.574 113.10 111.58 113.90 213.65 111.60 11.295 112.40 S1.181 113.20 122.34 114.00 229.08 111.70 14.716 112.50 58.275 113.30 133.65 2/9/00 9:2S:48 am page 4 HAMA HAMA GRAVEL PIT JUNE 2009 HYDROLOGICAL CALCULATIONS xxmxasaxsasxamssmxaxxsxxxxxsxxxxxxsascxs¢xz:xxxxxxaaxzsxxxxxxxxxxxxxx STAGE DISCHARGE TABLE OVERFLOW WEIR ID No. Emer3 Description: Emergency overflow Ratio (h:lv): 3.2100 weir length: 6.0000 ft. El: 110.00 ft. Weir Increm: 0.10 STAGE <--DISCHARGE---> STAGE <--DISCHARGE---> STAGE <--DISCHARGE---> STAGE <--DISCHARGE---> (ft) ---cfs-- ------- (ft) ---cfs-- ------- (ft) ---cfs-- ------- (ft) ---cfs-- ------- x xxxssa:saxscsssxxxsxxx -aaxxxxsaasss¢xsssxssxxxs_x �--xxz¢:sxsxxxx¢xxsxxxssa:zxasxsxassxxxxxxxxsaxx 110.00 0.0000 110.30 3.5869 110 60 11.295 110.90 22.861 110.10 0.6382 110.40 5.7309 110.70 14.716 111.00 27.599 110.20 1.8787 110.50 8.3007 110.80 18.569 0 Page 2 HAMAHAMA-STORAGE-DISCH.PRN 2/9/00 9:25:48 am page 1 HAMA HAMA GRAVEL PIT JUNE 2009 HYDROLOGICAL CALCULATIONS axaaassaaxxaaaam�xaac=sxxaaxac cxaxa x as as ssxxa=s=axaxxxxaaaaaxss STORAGE STRUCTURE LISTa TRAPEZOIDAL BASIN ID No. InfilA Description: infiltration (ea 5 acres) Length: 40.00 ft. width: 20.00 ft. Side Slope 1: 3 Side Slope 3: 3 Side Slope 2: 3 Side Slope 4: 3 infiltration Rate: 5.60 min/inch TRAPEZOIDAL BASIN ID No. InfilB Description: infiltration (169 acres) Length: 100.00 ft. width: 70.00 ft. Side Slope 1: 3 Side Slope 3: 3 Side Slope 2: 3 Side Slope 4: 3 infiltration Rate: 5.60 min/inch TRAPEZOIDAL BASIN ID No. Infilc Description: infiltration (169 acres) Length: 400.00 ft. width: 300.00 ft. Side Slope 1: 3 Side Slope 3: 3 Side Slope 2: 3 Side slope 4: 3 infiltration Rate: 5.60 min/inch 2/9/00 9:25:48 am page 2 HAMA HAMA GRAVEL PIT JUNE 2009 HYDROLOGICAL CALCULATIONS xxaxaxaa_xaxasxvxsax=aaaaxssassxxxxaxxxeaaaoxxxxxaxaa==xxxxxxxaxoxx-- STAGE DISCHARGE TABLE OVERFLOW WEIR ID No. Emerl Description: Emergency overflow Ratio (h:lv): 3.2100 weir length: 6.0000 ft. El: 110.00 ft. weir Increm: 0.10 STAGE <--DISCHARGE---> STAGE <--DISCHARGE---> STAGE <--DISCHARGE---> STAGE <--DISCHARGE---> (ft) ---cfs-- ------- (ft) ---cfs-- ------- (ft) ---cfs-- ------- (ft) ---cfs-- ------- a=acxaxxasasss=aasc=xxxxxaca=sxxxxcaxaaaasxssax===x=sxaxxxxxxssxxaaxa-----xas=sxaxa-----xamaxa------ 110.00 0.0000 110.30 3.5869 110.60 11.295 110.90 22.861 110.10 0.6382 110.40 5.7309 110.70 14.716 111.00 27.599 110.20 1.8787 110.50 8.3007 110.80 18.569 2/9/00 9:25:48 am page 3 HAMA HAMA GRAVEL PIT JUNE 2009 HYDROLOGICAL CALCULATIONS ssaamam¢¢xxsasasxssxsx¢assxxssxx¢axcsssaxmxaxaaaasasaaaxx==xax=sxssss STAGE DISCHARGE TABLE OVERFLOW WEIR ID No. Emer2 Description Emergency overflow Ratio (h:lv): 3.2100 weir length: 6.0000 ft. El: 111.00 ft. Weir Increm: 0.10 Page 1 � , HWAGEOSCIENCES INC. Geotechnical & Pavement Engineering- Hydrogeology • Gcoermironmetital • Inspection v Testing June 8,2009 HWA Project No. 2009-000 Task 010 Preferred Engineering, LLC PO Box 25422 Federal Way, Washington 98093 Attention: Mr. Steven Lee,P.E. Subject: Soil Laboratory Testing Report Hydraulic Conductivity and Grain Size Analysis PDLC -Hama Hama Soil Dear Mr. Lee: As requested, HWA GeoSciences Inc. (HWA)performed laboratory testing for the above referenced project. Herein we present the results of our laboratory analyses, which are summarized on the attached reports and in Table 1. The laboratory testing program was performed in general accordance with your instructions and appropriate ASTM Standards as outlined below. SAMPLE DESCRIPTION: The subject sample was delivered to our laboratory on May 22, 2009. The sample was designated as S-1. The sample was delivered in a plastic bag. Based on manual-visual methods,the soil description for the sample is as follows: S-1 Light grayish brown, well graded GRAVEL with sand(GW) PARTICLE SIZE ANALYSIS OF SOILS: The sample was split down to an appropriate P P specimen test size to determine the particle distribution in general accordance with ASTM D422. A#270 sieve was added to the sieve set to better quantify the silt fraction. The results are summarized on the attached Grain Size Distribution report, Figure 1, which also provides information regarding the classification of the sample and the moisture content at the time of testing. PERMEABILITY OF GRANULAR SOILS(CONSTANT HEAD METHOD): The coefficient of permeability (also commonly referred to as hydraulic conductivity) of the sample was measured in general accordance with method ASTM D2434. The sample was placed in the test apparatus loosely and was hand compacted to minimize voids. A low, constant, hydraulic head was applied to the sample. The test gradient was 0.12 cm/cm. The sample didn't settle during testing. The test results are detailed in Table 1. 19730-64th Avenue W. Suite 200 Lynnwood,WA 98036.5957 Tel: 425.774.0106 Fax: 425.774.2714 www.hwageo.com Table 1. Hydraulic Conductivity Sample ID Wet Moisture Dry Void Hydraulic Conductivity Density Content Density Ratio (cm/s) (pcfl (%) (Pcf) S-1 129.1 2.6 125.8 0.31 3.78 E-03 O.O CLOSURE: Experience has shown that test values on soil and other natural materials vary with each representative sample. As such, HWA has no knowledge as to the extent and quantity of material the tested samples may represent. HWA also makes no warranty as to how representative either the samples tested or the test results obtained are to actual field conditions. It is a well established fact that sampling methods present varying degrees of disturbance that affect sample representativeness. No copy should be made of this report except in its entirety. We appreciate the opportunity to provide laboratory testing services on this project. Should you have any questions or comments, or if we may be of further service,please call. Sincerely, HWA GEOSCIENCES INC. .144� Harold Benny Lorne A. Balanko,P. E. Materials Laboratory Manager Principal GRAVEL SAND SILT CLAY Coarse Fine FCoarse Medium Fine U.S. STANDARD SIEVE SIZES 3/4" 3" 1-1/2" 5/8" 3/8" #4 #10 #20 #40 #60 #100 #200 100� I I I I I I I I I I I I !I I I I I I 90 I I I I I 1 I I I I I I I I I I I I I I 80 = 1 I I I I I I I I 70 I I I I I I I I I 1 I I I I I I I I I I m 60 I I I I I I 1 I I W 50 Z LL I I I 1 I I I I I I I— 40 I 1 1 I I I I I I I z I I I I I I I I I C) 30 w 11 I I I I !I I I I I I 20 I I I I I I I I I I I I I I I I I 1 10 II I I 0 50 10 5 1 0.5 0.1 0.05 0.01 0.005 0.001 0.0005 GRAIN SIZE IN MILLIMETERS SYMBOL SAMPLE DEPTH(ft) CLASSIFICATION OF SOIL-ASTM D2487 Group Symbol and Name %MC LL PL PI Gravel Sand Fines • S-1 (GW)Light grayish brown,well graded GRAVEL with sand 3 62.7 35.6 1.8 PARTICLE-SIZE ANALYSIS Preferred Engineering OF SOILS �HWAGEOSCIENCES INCTHOD ASTM D422 C. PROJECT NO.: 2009000-TO1 O FIGURE: USDA United States A product of the National Custom Soil Resource Department of Cooperative Soil Survey, Agriculture a joint effort of the United Report for O NI ��� States Department of v Agriculture and other Mason Federal a encies State g County, Natural agencies including the Resources Agricultural Experiment Washington Conservation Stations, and local Service participants All 14 . i �,,4 � `•� of �!�' i � �r ``•i _ t ir 'IV r� t• i n I Mason T. q '"•�T � i � ail� � �4 .� - �+' A � 11l K J�' �j 1- � fi• A P .� �.,•Y +DNA y �� � � -,r. 41 IF a �Tf 1� LT ►2C • { n 1`� `►=It A j f May 15, 2009 Preface Soil surveys contain information that affects land use planning in survey areas. They highlight soil limitations that affect various land uses and provide information about the properties of the soils in the survey areas. Soil surveys are designed for many different users, including farmers, ranchers, foresters, agronomists, urban planners, community officials, engineers, developers, builders, and home buyers. Also, conservationists, teachers, students, and specialists in recreation, waste disposal, and pollution control can use the surveys to help them understand, protect,or enhance the environment. Various land use regulations of Federal, State, and local governments may impose special restrictions on land use or land treatment. Soil surveys identify soil properties that are used in making various land use or land treatment decisions. The information is intended to help the land users identify and reduce the effects of soil limitations on various land uses. The landowner or user is responsible for identifying and complying with existing laws and regulations. Although soil survey information can be used for general farm, local, and wider area planning,onsite investigation is needed to supplement this information in some cases. Examples include soil quality assessments (http:/!soils.usda.gov/sqi/) and certain conservation and engineering applications. For more detailed information, contact your local USDA Service Center(http://offices.sc.egov.usda.gov/locator/app? agency=nres) or your NRCS State Soil Scientist(http://soils.usda.gov/contact/ state_offices/). Great differences in soil properties can occur within short distances. Some soils are seasonally wet or subject to flooding. Some are too unstable to be used as a foundation for buildings or roads. Clayey or wet soils are poorly suited to use as septic tank absorption fields. A high water table makes a soil poorly suited to basements or underground installations. The National Cooperative Soil Survey is a joint effort of the United States Department of Agriculture and other Federal agencies, State agencies including the Agricultural Experiment Stations, and local agencies. The Natural Resources Conservation Service (NRCS) has leadership for the Federal part of the National Cooperative Soil Survey. Information about soils is updated periodically. Updated information is available through the NRCS Soil Data Mart Web site or the NRCS Web Soil Survey. The Soil Data Mart is the data storage site for the official soil survey information. The U.S. Department of Agriculture(USDA)prohibits discrimination in all its programs and activities on the basis of race, color, national origin, age, disability, and where applicable, sex, marital status, familial status, parental status, religion, sexual orientation, genetic information, political beliefs, reprisal, or because all or a part of an individual's income is derived from any public assistance program. (Not all prohibited bases apply to all programs.) Persons with disabilities who require alternative means 2 for communication of program information (Braille, large print, audiotape, etc.)should contact USDA's TARGET Center at(202) 720-2600 (voice and TDD). To file a complaint of discrimination, write to USDA, Director, Office of Civil Rights, 1400 Independence Avenue, S.W., Washington, D.C. 20250-9410 or call (800) 795-3272 (voice) or(202) 720-6382 (TDD). USDA is an equal opportunity provider and employer. 3 Contents Preface....................................................................................................................2 How Soil Surveys Are Made..................................................................................5 SoilMap......................................................................... ..... 7 SoilMap................................................................................................................8 Legend............ . . ....................................................................-.-..............9 MapUnit Legend................................................................................................10 MapUnit Descriptions........................................................................................10 MasonCounty, Washington............................................................................12 Gb—Grove cobbly sandy loam, 0 to 5 percent slopes................................12 Gn—Grove gravelly sandy loam, 30 to 45 percent slopes..........................12 Hf—Hoodsport gravelly sandy loam, 30 to 45 percent slopes....................13 Ma—Made land...........................................................................................14 Tn—Tidal marsh, 0 to 2 percent slopes......................................................14 References............................................................................................................16 4 How Soil Surveys Are Made Soil surveys are made to provide information about the soils and miscellaneous areas in a specific area. They include a description of the soils and miscellaneous areas and their location on the landscape and tables that show soil properties and limitations affecting various uses. Soil scientists observed the steepness, length, and shape of the slopes; the general pattern of drainage; the kinds of crops and native plants; and the kinds of bedrock. They observed and described many soil profiles. A soil profile is the sequence of natural layers, or horizons, in a soil. The profile extends from the surface down into the unconsolidated material in which the soil formed or from the surface down to bedrock. The unconsolidated material is devoid of roots and other living organisms and has not been changed by other biological activity. Currently, soils are mapped according to the boundaries of major land resource areas (MLRAs). MLRAs are geographically associated land resource units that share common characteristics related to physiography, geology, climate, water resources, soils, biological resources, and land uses (USDA, 2006). Soil survey areas typically consist of parts of one or more MLRA. The soils and miscellaneous areas in a survey area occur in an orderly pattern that is related to the geology, landforms, relief, climate, and natural vegetation of the area. Each kind of soil and miscellaneous area is associated with a particular kind of landform or with a segment of the landform. By observing the soils and miscellaneous areas in the survey area and relating their position to specific segments of the landform,a soil scientist develops a concept,or model, of how they were formed.Thus, during mapping, this model enables the soil scientist to predict with a considerable degree of accuracy the kind of soil or miscellaneous area at a specific location on the landscape. Commonly, individual soils on the landscape merge into one another as their characteristics gradually change. To construct an accurate soil map, however, soil scientists must determine the boundaries between the soils. They can observe only a limited number of soil profiles. Nevertheless, these observations, supplemented by an understanding of the soil-vegetation-landscape relationship, are sufficient to verify predictions of the kinds of soil in an area and to determine the boundaries. Soil scientists recorded the characteristics of the soil profiles that they studied. They noted soil color, texture, size and shape of soil aggregates, kind and amount of rock fragments, distribution of plant roots, reaction, and other features that enable them to identify soils. After describing the soils in the survey area and determining their properties, the soil scientists assigned the soils to taxonomic classes (units). Taxonomic classes are concepts. Each taxonomic class has a set of soil characteristics with precisely defined limits. The classes are used as a basis for comparison to classify soils systematically. Soil taxonomy, the system of taxonomic classification used in the United States, is based mainly on the kind and character of soil properties and the arrangement of horizons within the profile. After the soil scientists classified and named the soils in the survey area, they compared the 5 I Custom Soil Resource Report individual soils with similar soils in the same taxonomic class in other areas so that they could confirm data and assemble additional data based on experience and research. The objective of soil mapping is not to delineate pure map unit components; the objective is to separate the landscape into landforms or landform segments that have similar use and management requirements. Each map unit is defined by a unique combination of soil components and/or miscellaneous areas in predictable proportions. Some components may be highly contrasting to the other components of the map unit. The presence of minor components in a map unit in no way diminishes the usefulness or accuracy of the data. The delineation of such landforms and landform segments on the map provides sufficient information for the development of resource plans. If intensive use of small areas is planned, onsite investigation is needed to define and locate the soils and miscellaneous areas. Soil scientists make many field observations in the process of producing a soil map. The frequency of observation is dependent upon several factors, including scale of mapping, intensity of mapping, design of map units, complexity of the landscape, and experience of the soil scientist. Observations are made to test and refine the soil- landscape model and predictions and to verify the classification of the soils at specific locations. Once the soil-landscape model is refined, a significantly smaller number of measurements of individual soil properties are made and recorded. These measurements may include field measurements, such as those for color, depth to bedrock, and texture, and laboratory measurements, such as those for content of sand, silt, clay, salt, and other components. Properties of each soil typically vary from one point to another across the landscape. Observations for map unit components are aggregated to develop ranges of characteristics for the components. The aggregated values are presented. Direct measurements do not exist for every property presented for every map unit component. Values for some properties are estimated from combinations of other properties. While a soil survey is in progress, samples of some of the soils in the area generally are collected for laboratory analyses and for engineering tests. Soil scientists interpret the data from these analyses and tests as well as the field-observed characteristics and the soil properties to determine the expected behavior of the soils under different uses. Interpretations for all of the soils are field tested through observation of the soils in different uses and under different levels of management. Some interpretations are modified to fit local conditions, and some new interpretations are developed to meet local needs. Data are assembled from other sources, such as research information, production records, and field experience of specialists. For example, data on crop yields under defined levels of management are assembled from farm records and from field or plot experiments on the same kinds of soil. Predictions about soil behavior are based not only on soil properties but also on such variables as climate and biological activity. Soil conditions are predictable over long periods of time, but they are not predictable from year to year. For example, soil scientists can predict with a fairly high degree of accuracy that a given soil will have a high water table within certain depths in most years, but they cannot predict that a high water table will always be at a specific level in the soil on a specific date. After soil scientists located and identified the significant natural bodies of soil in the survey area, they drew the boundaries of these bodies on aerial photographs and identified each as a specific map unit.Aerial photographs show trees, buildings,fields, roads, and rivers, all of which help in locating boundaries accurately. 6 Soil Map The soil map section includes the soil map for the defined area of interest, a list of soil map units on the map and extent of each map unit, and cartographic symbols displayed on the map. Also presented are various metadata about data used to produce the map, and a description of each soil map unit. 7 f A V A W o N W N O W ' V 5264800 5264900 5265000 5265100 5265200 5265300 5265400 5265500 5265600 123'3'17" Z -40 it ,w x �► 00 Adwle NN cn m • _ yp o t "� •"i rrh•v,.J►� 'r l� v � rsd ��t; O m 3 +� r,n. :- "1a 01 of. y i ' ' ' ♦` '1' _ � W p • N dO % y r V ' •Y AM 45 s �r y.� } 0 ,� �,� 4�'•� ,+��+? ��l�'�'�,�'� �� s �� r-r'�' a �* 'grin ei ' : t -. ♦ A� C i .--Y r� �r O f . cn cnCD �•..- �:r • ,r' is r - . � _�7 o�o f_.• ., "4, _ d4#4� w - x 'k rr" ,,�, r �r .s +P '- SU O ` V , .,���� ,. - � 1 x1Mr e.� Yf� •shy„� ^1�.-• `► .� '. m o � a 0 0 A � A 123°2'17" S g 123'2'17" 5264800 5264900 52651000 52651100 5265200 52651300 5265400 5265500 5265600 A o A W V N W N Q W ' V Custom Soil Resource Report MAP LEGEND MAP INFORMATION Area of Interest(AOI) Z Very Stony Spot Map Scale: 1:5,970 if printed on A size(8.5"x 11")sheet. Area of Interest(AOI) +� Wet Spot Soils The soil surveys that comprise your AOI were mapped at 1:31,680. Soil Map Units a Other Special Line Features Please rely on the bar scale on each map sheet for accurate map Special Point Features Gully measurements. Blowout Short Steep Slope ® Borrow Pit Source of Map: Natural Resources Conservation Service Other Web Soil Survey URL: hftp://websoilsurvey.nres.usda.gov X Clay Spot Political Features Coordinate System: UTM Zone 10N NAD83 Closed Depression O Cities This product is generated from the USDA-NRCS certified data as of X Gravel Pit Water Features the version date(s)listed below. Gravelly Spot Oceans Landfill Soil Survey Area: Mason County,Washington Streams and Canals Survey Area Data: Version 4, Dec 5,2006 !. Lava Flow Transportation Marsh or swamp +++ Rails Date(s)aerial images were photographed: 8/6/2006 x Mine or Quarry Interstate Highways The orthophoto or other base map on which the soil lines were p Miscellaneous Water US Routes compiled and digitized probably differs from the background imagery displayed on these maps.As a result,some minor shifting p Perennial Water Major Roads of map unit boundaries may be evident. v Rock Outcrop Local Roads + Saline Spot Sandy Spot Severely Eroded Spot p Sinkhole a' Slide or Slip 0 Sodic Spot Spoil Area U Stony Spot Custom Soil Resource Report Map Unit Legend Mason County,Washington(WA645) Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI Gb Grove cobbly sandy loam,0 to 5 percent 63.2 38.6% slopes Gn Grove gravelly sandy loam,30 to 45 percent 56,8 34 7% slopes Hf Hoodsport gravelly sandy loam, 30 to 45 i 32.01 percent slopes Ma Made land 6.1 3.7% Tn Tidal marsh, 0 to 2 percent slopes 1.3 0 8°!° Subtotals for Soil Survey Area 159.4 97.3'4 ------._ Totals for Aroa of lnterm 163.8 100.0'/. Map Unit Descriptions The map units delineated on the detailed soil maps in a soil survey represent the soils or miscellaneous areas in the survey area. The map unit descriptions, along with the maps, can be used to determine the composition and properties of a unit. A map unit delineation on a soil map represents an area dominated by one or more major kinds of soil or miscellaneous areas. A map unit is identified and named according to the taxonomic classification of the dominant soils. Within a taxonomic class there are precisely defined limits for the properties of the soils. On the landscape, however, the soils are natural phenomena, and they have the characteristic variability of all natural phenomena. Thus, the range of some observed properties may extend beyond the limits defined for a taxonomic class. Areas of soils of a single taxonomic class rarely, if ever, can be mapped without including areas of other taxonomic classes. Consequently, every map unit is made up of the soils or miscellaneous areas for which it is named and some minor components that belong to taxonomic classes other than those of the major soils. Most minor soils have properties similar to those of the dominant soil or soils in the map unit, and thus they do not affect use and management. These are called noncontrasting, or similar, components. They may or may not be mentioned in a particular map unit description. Other minor components, however, have properties and behavioral characteristics divergent enough to affect use or to require different management. These are called contrasting, or dissimilar,components.They generally are in small areas and could not be mapped separately because of the scale used. Some small areas of strongly contrasting soils or miscellaneous areas are identified by a special symbol on the maps. If included in the database for a given area, the contrasting minor components are identified in the map unit descriptions along with some characteristics of each. A few areas of minor components may not have been observed, and consequently they are not mentioned in the descriptions, especially where the pattern was so complex that it was impractical to make enough observations to identify all the soils and miscellaneous areas on the landscape. 10 Custom Soil Resource Report The presence of minor components in a map unit in no way diminishes the usefulness or accuracy of the data. The objective of mapping is not to delineate pure taxonomic J PP 9 classes but rather to separate the landscape into landforms or landform segments that have similar use and management requirements. The delineation of such segments on the map provides sufficient information for the development of resource plans. If intensive use of small areas is planned, however, onsite investigation is needed to define and locate the soils and miscellaneous areas. An identifying symbol precedes the map unit name in the map unit descriptions. Each description includes general facts about the unit and gives important soil properties and qualities. Soils that have profiles that are almost alike make up a soil series. Except for differences in texture of the surface layer, all the soils of a series have major horizons that are similar in composition, thickness, and arrangement. Soils of one series can differ in texture of the surface layer, slope, stoniness, salinity, degree of erosion, and other characteristics that affect their use. On the basis of such differences, a soil series is divided into soil phases. Most of the areas shown on the detailed soil maps are phases of soil series. The name of a soil phase commonly indicates a feature that affects use or management. For example, Alpha silt loam, 0 to 2 percent slopes, is a phase of the Alpha series. Some map units are made up of two or more major soils or miscellaneous areas. These map units are complexes, associations, or undifferentiated groups. A complex consists of two or more soils or miscellaneous areas in such an intricate pattern or in such small areas that they cannot be shown separately on the maps.The pattern and proportion of the soils or miscellaneous areas are somewhat similar in all areas. Alpha-Beta complex, 0 to 6 percent slopes, is an example. An association is made up of two or more geographically associated soils or miscellaneous areas that are shown as one unit on the maps. Because of present or anticipated uses of the map units in the survey area, it was not considered practical or necessary to map the soils or miscellaneous areas separately. The pattern and relative proportion of the soils or miscellaneous areas are somewhat similar. Alpha- Beta association, 0 to 2 percent slopes, is an example. An undifferentiated group is made up of two or more soils or miscellaneous areas that could be mapped individually but are mapped as one unit because similar interpretations can be made for use and management. The pattern and proportion of the soils or miscellaneous areas in a mapped area are not uniform. An area can be made up of only one of the major soils or miscellaneous areas, or it can be made up of all of them. Alpha and Beta soils, 0 to 2 percent slopes, is an example. Some surveys include miscellaneous areas. Such areas have little or no soil material and support little or no vegetation. Rock outcrop is an example. 11 Custom Soil Resource Report Mason County, Washington Gb -Grove cobbly sandy loam, 0 to 5 percent slopes Map Unit Setting Mean annual precipitation: 90 inches Mean annual air temperature:48 degrees F Map Unit Composition Grove and similar soils: 100 percent Description of Grove Setting Landform. Outwash plains Parent material. Glacial outwash Properties and qualities Slope: 0 to 5 percent Depth to restrictive feature: More than 80 inches Drainage class: Somewhat excessively drained Capacity of the most limiting layer to transmit water(Ksat): High (1.98 to 5.95 in/hr) Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding, None Available water capacity: Low (about 3.0 inches) Interpretive groups Land capability(nonirrigated): 4s Typical profile 0 to 13 inches: Cobbly sandy loam 13 to 28 inches: Very gravelly sandy loam 28 to 60 inches: Very gravelly loamy sand Gn—Grove gravelly sandy loam, 30 to 45 percent slopes Map Unit Setting Mean annual precipitation: 90 inches Mean annual air temperature: 48 degrees F Map Unit Composition Grove and similar soils: 100 percent Description of Grove Setting Landform: Outwash plains Parent material: Glacial outwash Properties and qualities Slope: 30 to 45 percent 12 Custom Soil Resource Report Depth to restrictive feature: More than 80 inches Drainage class: Somewhat excessively drained Capacity of the most limiting layer to transmit water(Ksat): High (1.98 to 5.95 in/hr) Depth to water table. More than 80 inches Frequency of flooding: None Frequency of ponding: None Available water capacity: Low (about 3.2 inches) Interpretive groups Land capability(nonirrigated): 6e Typical profile 0 to 13 inches: Gravelly sandy loam 13 to 28 inches: Very gravelly sandy loam 28 to 60 inches: Very gravelly loamy sand Hf—Hoodsport ds o r p rt gravelly sandy loam, 30 to 45 percent slopes Map Unit Setting Mean annual precipitation: 60 inches Mean annual air temperature: 50 degrees F Map Unit Composition Hoodsport and similar soils: 100 percent Description of Hoodsport Setting Landform. Till plains Parent material. Basal till Properties and qualities Slope: 30 to 45 percent Depth to restrictive feature: 20 to 40 inches to dense material Drainage class: Moderately well drained Capacity of the most limiting layer to transmit water(Ksat): Very low to moderately low (0.00 to 0.06 in/hr) Depth to water table: About 18 to 36 inches Frequency of flooding: None Frequency of ponding: None Available water capacity:Very low (about 1.6 inches) Interpretive groups Land capability(nonirrigated): 6e Typical profile 0 to 5 inches: Gravelly sandy loam 5 to 24 inches: Very gravelly sandy loam 24 to 60 inches: Gravelly sandy loam 13 Custom Soil Resource Report Ma—Made land Map Unit Setting Mean annual precipitation: 0 inches Mean annual air temperature: 32 degrees F Map Unit Composition Made land: 100 percent Description of Made Land Interpretive groups Land capability(nonimgated): 8s Typical profile 0 to 6 inches: Variable Tn—Tidal marsh, 0 to 2 percent slopes Map Unit Setting Elevation: 0 to 100 feet Mean annual precipitation: 20 to 30 inches Mean annual air temperature: 48 to 52 degrees F Frost-free period: 170 to 210 days Map Unit Composition Tidal marsh and similar soils: 100 percent Description of Tidal Marsh Setting Landform: Coastal plains Properties and qualities Slope: 0 to 2 percent Depth to restrictive feature. More than 80 inches Drainage class: Very poorly drained Capacity of the most limiting layer to transmit water(Ksat). Moderately high to high (0.57 to 1.98 in/hr) Depth to water table:About 0 inches Frequency of flooding: Frequent Frequency of ponding: Frequent Maximum salinity: Slightly saline to moderately saline (8.0 to 16.0 mmhos/cm) Sodium adsorption ratio, maximum: 10.0 Available water capacity: High (about 10.0 inches) Interpretive groups Land capability(nonirrigated). 6w 14 Custom Soil Resource Report Typical profile 0 to 6 inches: Fine sandy loam 6 to 60 inches: Stratified fine sandy loam to silty clay loam 15 References American Association of State Highway and Transportation Officials(AASHTO).2004. Standard specifications for transportation materials and methods of sampling and testing. 24th edition. American Society for Testing and Materials (ASTM). 2005. Standard classification of soils for engineering purposes. ASTM Standard D2487-00. Cowardin, L.M., V. Carter, F.C. Golet, and E.T. LaRoe. 1979. Classification of wetlands and deep-water habitats of the United States. U.S. Fish and Wildlife Service FWS/OBS-79/31. Federal Register. July 13, 1994. Changes in hydric soils of the United States. Federal Register. September 18, 2002. Hydric soils of the United States. 6.0 Version ,2006- Field indicators of hydric soils Hurt G.W.,and L.M.Vasilas, editors. in the United States. National Research Council. 1995. Wetlands: Characteristics and boundaries. Soil Survey Division Staff. 1993. Soil survey manual. Soil Conservation Service. U.S. Department of Agriculture Handbook 18. http.//solls.usda.gov/ Soil Survey Staff. 1999. Soil taxonomy: A basic system of soil classification for making and interpreting soil surveys. 2nd edition. Natural Resources Conservation Service, U.S. Department of Agriculture Handbook 436. http //soils.usda.gov/ Soil Survey Staff. 2006. Keys to soil taxonomy. 10th edition. U.S. Department of Agriculture, Natural Resources Conservation Service. http://Soils.usda.govi Tiner, R.W., Jr. 1985. Wetlands of Delaware. U.S. Fish and Wildlife Service and Delaware Department of Natural Resources and Environmental Control, Wetlands Section. United States Army Corps of Engineers, Environmental Laboratory. 1987. Corps of Engineers wetlands delineation manual. Waterways Experiment Station Technical Report Y-87-1. United States Department of Agriculture, Natural Resources Conservation Service. National forestry manual. http.//soils.usda.gov/ United States Department of Agriculture, Natural Resources Conservation Service. National range and pasture handbook. http.//www.glti.nres.usda.gov/ United States Department of Agriculture, Natural Resources Conservation Service. National soil survey handbook, title 430-VI. http.//soils usda.gov/ United States Department of Agriculture, Natural Resources Conservation Service. 2006. Land resource regions and major land resource areas of the United States, the Caribbean, and the Pacific Basin. U.S. Department of Agriculture Handbook 296. http://Soils.usda.gov/ 16 1 I Custom Soil Resource Report United States Department of Agriculture, Soil Conservation Service. 1961. Land capability classification. U.S. Department of Agriculture Handbook 210. 17 1 oa .T Sit CAN T , - Jmill _. . r co r ','Aso/ a� ;%l.'• �.� • too 2-*Z z� 6 S W w +� A EA� J ,SO /f \ "'-- RECESSIONAL OUTWASH DELTA 1 L Iry F,�TRATtOf! / � f wwTCtt turPLv �zA 1.006 GPM Y �t Zoo'"fie 11m4L -c-v- �+ S rr PLANS' yo AREA d) fs ►4A T /Z �p 0 t 2T PT FIGURE17 DRILL HOLE LOCATION MAP TOWNSHIP 24 NORTH, RANGE 3 WEST oUIFE LV1�EN LOCATION MAP WHATCOM "E WASHINGTON R 3 W SANJUAN e 1 1 11 1 �'- wo v owoRT •SITE '� SIT °" T 3KAGn 24 M. oNN GELE TMNEEII �'a�+To'+ N E � SNOHOMISH 47°32'40"N Latitude "*E CLALLAM s! se -,gyp 123'02'30"W Longitude - `�� JEFFERSON LNNe No sNrHosesH�' S M TTL EELL ASO ISE'RT jj__ KFNr TII YENo P— �H000s w� VNRH KING RAYS ' K. T "uNcuw BEACH H BOR UCNLEr DIRECTIONS TO SITE: °° E ° '"` PIERCE HORES THE SITE IS LOCATED ON THE WESTERN SIDE OF US HIGHWAY 101, NEAR MILE THURSTON R NER CENTR/�LM MARKER 320, LESS THAN ONE MILE A B Yw THEN La LEWIS Pn — SOUTH OF ELDON, WA. "�, Lobo 4 PACIFIC wswoa �ssrRorx Sf CH — i�w�c _ IAKUM uETu� SKAMANIA "OCN COWLITZ .� GTMAME •Nf,tT. l �E680 NELEM NOTE: w000AN�� CLA K� USGS TOPOGRAPHIC QUADRANGLE MAP PROJECT `E EA-E (ELDON, 1985)REPRODUCED USING MAPTECH VICINITY MAP � lONEVIlE INC.,TERRAIN NAVIGATOR PRO SOFTWARE. • CWrvN.Ea -' Lid.-,�. _. . y__..,.j_....�._._.�__.._........... ..+.�_. 11j F PROPERTY BOUNDARY! I PERMIT �US HIGHWAY 101 BOUNDARY / SITE ACCESS / 28 27 ( / 33 34 _ 774 I � a JORSTED CREEK t/► �. 0 3000 6000 SCALE IN FEET - s GARRISON RESOURCE GROUP,INC. DATE: 08-06-08 Figure JA _ DWN: MPM VICINITY MAP ------------ '� REQ. BY:RG Hama Hama Pit PRJ. MGR:JBA CHK Company P Hama Hama C ' CHK Y 1157 3rd Avenue,Ste.220B Longview,WA 98632 APPR: Mason County, Washington (360)200-4803 IPROJ.#:1744,0]j Section 27, Township 24N, Range 3W aIAZvAt, vl EW OF ppbZ7tj!:5r S(It- PERMIT BOUNDARY 3 �,, `. �j Yk;-'►f . : 2 2, `.\94� ------ PARCEL LINES � e �`� ` �♦�:. *' lea.. �' ♦ �, � i 7gpoo'� 32427 PARCEL NUMBERS .fit p 0004000 BERS Y � 127 GEOREFERENCE "� ' ;'� ♦ 33 34 (SECTION CORNER) O o SUBJECT PROPERTY OWNERSHIP INFORP 324276004000 o N PARCEL NUMBER OWNER NAME OWNE R N 32427 AQUA CUL 0004000 HAMA HAMA COMPANY LILLIWAUI ADJACENT PROPERTY OWNERSHIP INFOR PARCEL NUMBER OWNER NAME OWNE r 324280000000 324281000010 324270000010 O�i 324271400000 AQUA CUL ' n �y `•. a ��^ 324260004000 HAMA HAMA COMPANY •�+*4VLS� t, * -" ^�'/ LILLIWAUI � 324274470940 324340000000 324331100000 DEPT.OF l 3242700600000 STATE OF WASHINGTON STATE L 4" O (US-101) PO c * OLYMPIA ' 324340000000 1 / 4r _ 3242700600000 800 1600 y4 tHit-C n 1t4AQE PATH . . -� . . �.� . 1�`^ — -- PERMIT BOUNDARY \� 1 1149 (183 ACRES) WE`IfBUFFER W ���L SITE ACCESS - — . — - SETBACK(= 11 ACRES) EXISTINGTOPOGRAPH' EXISTING TOPOGRAPH' CROSS SECTION LOCAL GA^A (SEE FIGURE 6) SAFETY BERM ------ EXISTING DISTURBED A o fill I ------I (PER DNR AERIAL ANAL WETLAND 250'WETLAND BUFFER It tit 4ri 'll, 28127 GEOREFERENCE ` 1 2 `\_) ;��- /', ' 1\\►1 \\\\1\\ I 33 34 (SECTION CORNER) I I \\ ., „ /, / 1\\\ \\I\\ EARTH MATERIAL DISP( \\\ \\\ ,�,��, \,", 1 , I►1 I 1 I I I �IIII1Il11TCI� (SEE NOTE 2) SAFETY BERM aw PERMIT BOUNDARY (183 ACRES) WETLAND, -► _ ,__�---__---� �_ \► BUFFER y L� SITE ACCESS SETBACK(- 11 ACRES) 01 2501W EXISTING TOPOGRAPH' J EXISTING TOPOGRAPH` _ �\ - -��+`.`` /� H /f\ v CROSS SECTION LOCA- \\ \� (SEE FIGURE 6) SAFETY M-1 I BERM WETLAND lilt �I . I _► :,/�,_ ^/� `, %' ' (35 ACRES) kill 1`'ttt'tt+it�t\++� - — — — - 250'WETLAND BUFFER ,+t+ 28127 Ilk �`1 - t, GEOREFERENCE �� ►I lilti 'i 8 l l 33 34 (SECTION CORNER) � �- /-,, ► ►( ,,__;� iitt ,tit 11 � i ,i''i' _ _ 141i 1�II t�t1 � i 4b:") ►�'" %� \` ���ii �I'`It ttti I ® EARTH MATERIALDISP( I V t+t t\`t\+` M-2 , t` (SEE NOTE 2) ►► �� (35 ACRFS) ++ ,+ B' SAFETY BERM II �.f/. %,, �'+ 1 jlil titilt lilt /, / ► r I TOPSOIL STORAGE ARE (35 ACRES) PERMANENT MARKER (LINE OF SIGHT, MARKE -5 `� M4 1 � '��; �/ INSTALLED ONE SEGME R-4 R-3 (31 ACRES) -� (35 ACRES); �� , MINING SEGMENT 8 RECLAMATION SEQUEN 5 M-2 MINING SEGMENT 300' r R-1 RECLAMATION SEQUEN (SEE NOTE 3) t qpo' ,-t `� ( ,'�-� i /� '. r r/, / , �.� DIRECTION OF MINING / 1ST PHASE OPEN AREA WITH LEGEND: TEMPORARY INFILTRATION • POND(5.0 ACRES-GRAVEL) �R INING M-1 AREA LEFT PROPERTY BOUNDARY U TURBED UNTIL NEEDED. • PERMIT BOUNDARY (183 ACRES) a. _ . W SETBACK (• 11 ACRES) c O < EXISTING TOPOGRAPHY (100' INTERVALS) m a E N m w m o c�z EXISTING TOPOGRAPHY 20' INTERVALS < E M v O - ( ) 5 Z_ � N c 0 o CROSS SECTION LOCATION � = o'g ' �•, (SEE FIGURE 6) _ 3 ------I EXISTING DISTURBED AREA a 3.8 ACRES f= 04 o /i - I------� (PER DNR AERIAL ANALYSIS 02-01-06) c C/ o d ( 1 WETLAND N ` - — — — - 250'WETLAND BUFFER IQ I 28127 GEOREFERENCE � (C 33 r34 (SECTION CORNER) ' EARTH MATERIAL DISPOSAL SITE FINAL M FILTR PON[ (SEE NOTE 2) Q (S P R CONSTR. �l SAFETY BERM o c � WELL EXISTING BASIN/PROJECT BOUNDARY Q w i a / o0xaUQa -► EXISTING DRAINAGE BASIN DS PATHWAY -- N 28 300' _ _ U PATHWAY: • OV RLAND= 8 EXISTING BASIN / L -26. BOUNDARY a TCH= 64 EX.AREA= 179 ACRES 0. 600 1200 W® N; N �+ N SCALE IN FEET C. PE-SSE-JOBS`,2008-PE'600-HAMA-HAMAI FROM GRG\HAMA HAMA-STANARD\1744.01-FIGURES XXXX.DWG L LOAND. TESC SPECIFIC LEGEND: - - — PROPERTY BOUNDARY __40!_� RECLAIMED TOPOGRAPHY* ® EARTH MATERIAL DISPOSAL SITE (20'INTERVALS;100'INDEX CONTOURS) (SEE FIGURE NOTE 2) — �— E UPSTREAM CUTOFF DITCH PERMIT BOUNDARY(183 ACRES) WETLAND WELL (SEE FIGURE 2B FOR DETAILS) SETBACK x SILT FENCE 250'WETLAND BUFFER FINAL DRAINAGE PATTERNS* (SEE FIGURE 2B FOR DETAILS) EXISTING TOPOGRAPHY (20'INTERVALS; 100'INDEX CONTOURS) 28127 GEOREFERENCE LIMITS OF DISTURBANCE 33 34 (SECTION CORNER) 0 (= o 164 ACRES) �0cc c � rn CL L 07 EROSION CONTROL NOTES: Q a E o cat — U 1. BEFORE ANY CONSTRUCTION OR DEVELOPMENT ACTIVITY OCCURS, A PRE-CONSTRUCTION a) ca cc cv H MEETING MUST BE HELD WITH MASON COUNTY. �i U= E c n Lmc) M Cc 7 L 2. ALL LIMITS OF CLEARING AND AREAS OF VEGETATION PRESERVATION AS PRESCRIBED ON I.- cc co U 3 WELL r THE PLAN(S) SHALL BE CLEARLY FLAGGED IN THE FIELD AND OBSERVED DURING = E a o — - ? CONSTRUCTION. Cc co F' cc �L SITE ACCESS 2 N I ♦ t�`� 3. ALL REQUIRED SEDIMENTATION/EROSION CONTROL FACILITIES MUST BE CONSTRUCTED AND FIRST PHASE-TEMPORARY TESC POND ♦`� IN OPERATION PRIOR TO LAND CLEARING AND/OR CONSTRUCTION TO ENSURE THAT WITH CONTROL OVERFLOW STRUCTURE 250 SEDIMENT LADEN WATER DOES NOT ENTER THE NATURAL DRAINAGE SYSTEM. ALL EROSION (NOT TO SCALE) AND SEDIMENT FACILITIES SHALL BE MAINTAINED IN A SATISFACTORY CONDITION UNTIL SUCH CD G" / TIME THAT CLEARING AND/OR CONSTRUCTION IS COMPLETE AND POTENTIAL FOR ON-SITE I 100'J EROSION HAS PASSED. THE IMPLEMENTATION, MAINTENANCE, REPLACEMENT AND 100. ADDITIONS TO EROSION/SEDIMENTATION CONTROL SYSTEMS SHALL BE THE RESPONSIBILITY OF THE PERMITEE. 4. THE EROSION AND SEDIMENTATION CONTROL SYSTEMS DEPICTED ON THIS DRAWING ARE I O m I INTENDED TO BE MINIMUM REQUIREMENTS TO MEET ANTICIPATED SITE CONDITIONS. AS CONSTRUCTION PROGRESSES AND UNEXPECTED OR SEASONAL CONDITIONS DICTATE, THE PERMITEE SHALL ANTICIPATE THAT MORE EROSION AND SEDIMENTATION CONTROL ao oO p0 yo w� FACILITIES WILL BE NECESSARY TO ENSURE COMPLETE SILTATION CONTROL ON THE CID PROPOSED SITE. DURING THE COURSE OF CONSTRUCTION, IT SHALL BE THE OBLIGATION zoo• l AND RESPONSIBILITY OF THE PERMITEE TO ADDRESS ANY NEW N I .MCP I CO DITIONS THAT MAY BE a, t zoo zoo, _ CREATED BY THE ACTIVITIES AND TO PROVIDE ADDITIONAL FACILITIES, OVER AND ABOVE o 010 MINIMUM REQUIREMENTS, AS MAY BE NEEDED, TO PROTECT ADJACENT PROPERTIES AND N a WATER QUALITY OF THE RECEIVING DRAINAGE SYSTEM. PERMANENT BIOSWALE/ 5. APPROVAL OF THIS PLAN IS FOR EROSION/SEDIMENTATION CONTROL ONLY. IT DOES NOT Ui VEGETATED SWALE H Z 0 D. 1 (NOT TO SCALE) CONSTITUTE AN APPROVAL OF STORM DRAINAGE DESIGN, SIZE NOR LOCATION OF PIPES, o o a a- RESTRICTORS,CHANNELS,OR RETENTION FACILITIES. I SILT FENCE 30' + 80 60.4p CUTOFF DITCH 6. IN ANY AREA WHICH HAS BEEN STRIPPED OF VEGETATION AND WHERE NO FURTHER WORK IS 120• loot ANTICIPATED FOR A PERIOD 30 DAYS OR MORE, ALL DISTURBED AREAS MUST BE LIMITS OF 160740 —� IMMEDIATELY STABILIZED WITH MULCHING, GRASS PLANTING OR OTHER APPROVED EROSION M DISTURBANCE / 780' CONTROL TREATMENT APPLICABLE TO THE TIME OF YEAR OR HAVE NO RUNOFF DRAINING I 240220 200' / N OFF THE PROJECT SITE. GRASS SEEDING ALONE WILL BE ACCEPTABLE ONLY DURING THE z60• MONTHS OF APRIL THROUGH SEPTEMBER, INCLUSIVE. SEEDING MAY PROCEED, HOWEVER, 3 2e0 • WHENEVER IT IS IN THE INTEREST OF THE PERMITEE, BUT MUST BE AUGMENTED WITH a li 3 sea 300' MULCHING, NETTING OR OTHER TREATMENT APPROVED BY THE COUNTY OR PERMIT I ` CONDITIONS,OUTSIDE THE SPECIFIED TIME PERIOD. W II 7\ c c I _ a 7. FOR ALL EROSION/SEDIMENTATION CONTROL PONDS A MINIMUM HEIGHT OF THREE(3) FEET, 28 27 - - - - _— - 300' CUTOFF DITCH 3:1 SIDE SLOPES. C) N c 33 34 - � - 8. A TEMPORARY GRAVEL CONSTRUCTION ENTRANCE,24 FEET X 50 FEET X 8 INCHES OF 4 TO 6 INCH QUARRY SPALLS SHALL BE LOCATED AT ALL POINTS OF VEHICULAR INGRESS AND EGRESS TO THE CONSTRUCTION SITE. c i Q I TEMPORARY SLOPES WITH EXPOSED SOILS SHALL HAVE DOZER TRACKS PERPENDICULAR Q FIGURE NOTES: 0 700 1 400 TO THE SLOPE TO PREVENT CONCENTRATED FLOWS. 1. BASE MAP&TOPOGRAPHY OBTAINED ONLINE FROM MASON COUNTY ASSESSOR AT WEB ADDRESS;HTTP/MIAPMASON.CO.MASON.WAUSIWEBSITEMASON. 2. EARTH MATERIAL DISPOSAL SITE;MASON COUNTY GRADING PERMIT GRDa"0009. SCALE IN FEET SILT FENCE DETAIL STRAW BALE BARRIER INSTALLATION CROSS SECTION; INSTALLED STRAW BALE BRUSH BARRIER STORMNATER NAXAaEXE.W :•GAWAL FOR THE P.ICET SOUND RAS134 -- s-TORAWATE4 YANAGEY.ENT yatr-:aL FOR THE: PUGET SOUND AAStH _ NOT TO SCALE Figure ;I-5.20 Proper InstaLlation of a Straw aele Barrier Figure 11-5.19 cross-section of a Pre"cly Installed Straw Sale Barrier t:aiaf are -tec-mlwol :tiow file FILTER FABRIC MATERIAL 60" WIDE ROLLS. USE STAPLES OR WIRE RIN65 TO A TTA CH 1 . -xcavato the trench. 2. 'lace anc stake straw �-a1es . 611d171jMore Cr 'yf� 1; 1111 1 'yroacte0 Sn�' LO FABRIC TO WIRE. 2"BY 2"14 6A. WIRE FABRIC OR EQUIV. �'"" ;- fi�te}rc inch ({((( `•f�. 1 '"*+�` BURY BOTTOM OF FABRIC MATERIAL -3•. �! �' �^ 4- IN 8"BY 12" TRENCH �: ba a;ow -- ,i-"__ - -•.h - - L Lj, 2. The rerlaining steps for inacallinq a etsav bal* barrier for sheet flow w app:icatzons apply here, with the f;4ilowing addition. 2. The barriar shall be extended to suet a kangth that the Sott ms of the end / bales are F.ig Ar is elo!yptltu ,%han ttiA =oprot t+� lowest mi3dla heylA c`1irooggh, or�ov*els ►: � �4 ,iroina Itt`ltri�'l t..`do ,�(11 flow a --her + �� /1•`- y.: K.....� ;..1k • S La � era aha31. be ta��r� iaspseted fn�a'k#..�' J$typc i+�h ranofi- ^o pducinq-y � rai'a>€a at le i2Y da during Fro1O j&1nlal:. ./'r ,.' Ste• y /�'''� f CIO" a-te FILTER FABRIC MATERIAL nti°ps► shall be paid to the repairof daiagid baloe, and ryas, and Jf �- ��j+j� undercutting bNMatJn.baleundercutting e Xecesear repairs to Darr_ere or r6 \\\ y W' + pi7cocnen: of bales *..all by nccoepltchad 2"BY 2"BY 14 6A. WIRE 3. wedge loose straw between 4. Backtil l• and toeipacw the proslptly. FABRIC OF EQUIV bales. excavated soil,, • Sodimant depoe.ts should be raoibved after each r'jnoff-producing rainfall;. They Must be removed when the level.of deposiciun reaches approzimaveiy. cna Aslf the CVSTRUCT;R2 GF A STRAA SALE.8ARRIER height of the barrier. PROVIDE 314"-1.5" WASHED GRAV - • 1►gyt RedLaent depmeit cemainin9.;a place attar the straw male barrier is no BACKFILL IN TRENCH AND ON BOTH longer required shall !ze dressed to eoaform to the ixircing grade, pra4pstred and seeded. SIDES OF FILTER FENCE FABRIC ON THE SURFACE. - a=- =emvora ,fn11 pgrebanent erosion and sadiment coatzb6•'&rca0ticea at-.ail oe maintained wild,' r r'ap}t:rgd•as needed =o assure ooatincoQ• pstfdh�tzice of their 4 intended tuactioeb` latenarce {r_d repair sha'11.-hi c.. cted in accordance with an approved ! . Ail Lamporary erosion and`k.4w A .04nx^oL Msasorea shall be remc va$ uithir. 2"BY 4" WOOD POST ALT. 3C dnye after final site stalftZflioin`!�1 aa:hi'eved cr after _tip taraporary i3!!Ps — are no longer needed. Trapped sed4jllegt shg1L be rem-red or stabilised on site. STEEL FENCE POSTS. "" Disturbed soil areas resulting Cron redolral sha11 be permanently stabilized. NOTES: II 1. FOR SHEET RUNOFF OR FOLLOWING DISCHARGE FROM A SEDIMENT TRAP OR POND. 1 --of-its A shop-jld.,4e hi gh4r. :,'1dr ;poi nt a 2. MAXIMUM SLOPE STEEPNESS PERPENDICULAR TO FENCE LINE IS 1:1. rRUPf.R ?LACEMENT OF STRAW BALE BARRIER 1` DRAINAGE MAY 3. MAXIMUM SHEET OR OVERLAND FLOW PATH LENGTH TO THE FENCE OF 100 FT. FIGURE NOTES: 4. IF 50%OR LESS OF THE SOIL, BY WEIGHT, IS FINE PARTICLES SMALLER THAN THE U.S. 1. SILT FENCE DETAIL OBTAINED FROM STEVE LEE;PREFERRED ENGINEERING, INC. STANDARD SIEVE NO. 200, THE EOS SHOULD BE EQUAL TO OR SMALLER THAN THE 2. STRAW BALE BARRIER INSTALLATION AND CROSS SECTION OBTAINED FROM SIEVE SIZE THAT 85%OF THE SOIL CAN PASS THROUGH. STEVE LEE; PREFERRED ENGINEERING, INC.FROM STORMWATER MANAGEMENT MANUAL FOR THE PUGET SOUND BASIN(FEBRUARY, 1992). 5. THE TRENCH SHALL BE BACKFILLED WITH 3/4"MINIMUM DIAMETER WASHED GRAVEL. GARRISON RESOURCE GROUP,INC. DATE: 07-21-09 Figure 2B 6. FILTER FABRIC FENCES SHALL BE REMOVED WHEN THEY HAVE SERVED THEIR _ _ TESC Plan - Detail Map USEFUL PURPOSE, BUT NOT BEFORE THE UPSLOPE AREA HAS BEEN PERMANENTLY - —- --fi DWN: MPM Hama Hama Pit STABILIZED. PROJ:#1744.01 Hama Hama Company 7. FILTER FABRIC FENCES SHALL BE INSPECTED IMMEDIATELY AFTER EACH RAINFALL 1157 3rd enue,Ste.2206 Longview,WA Mason County Washington Av AND AT LEAST DAILY DURING PROLONGED RAINFALL, ANY REPAIRS SHALL BE MADE 1 (360)200-4803 1 1 APPR: Section 27, Township 24N, Range3W, W.M. IMMEDIATELY. 1 ST PHASE OPEN AREA WITH TEMPORARY INFILTRATION LEGEND: • POND(5.0 ACRES-GRAVEL) R�*INING M-1 AREA LEFT . . PROPERTY BOUNDARY / UNPfrSTURBED UNTIL NEEDED. • •• �: — PERMIT BOUNDARY (183 ACRES) s P a _ SETBACK (• 11 ACRES) C 3 I - w > ° a i F 50' EXISTING TOPOGRAPHY (100' INTERVALS) w = tda r m • ua E � � o ��oo EXISTING TOPOGRAPHY (20' INTERVALS) E, Gw m U 5 2)z M m c a o CROSS SECTION LOCATION " O E _ 'o N ;SEE FIGURE 6) i m a 0 0 f R-S I J WETLAND U C w ct Q — - (3s.�cRes) 1 250' WETLAND BUFFER �1�7 GEOREFERENCE � 33134 (SECTION CORNER) oa • � M-2 EARTH MATERIAL DISPOSAL SITE R 1 \ (SEE NOTE 2) I O � j35 aceesj SAFETY BERM �1-3 FINAL M FILTR PON( (SE P R CONSTR. WELL R-2 135 ACRES) TOPSOIL STORAGE AREAS " a � / R3 PERMANENT MARKER m R-4 v (LINE OF SIGHT, MARKERS WILL BE < w _ ct us 'kcRES) INSTALLED ONE SEGMENT AT A TIME) ocl a c� a � 13I U RESI % MINING SEGMENT& N RECLAMATION SEQUENCE BOUNDARY it 28 300' M-2 MINING SEGMENT U PATHWAY: • ' R-1 RECLAMATION SEQUENCE w OV BLAND= 8 (SEE NOTE 3) L 26. ITCH=. _ LA DIRECTION OF MINING NOTES: 0 600 1200 Luu 1. BASE MAP&TOPOGRAPHY OBTAINED ONLINE FROM MASON COUNTY ASSESSOR AT WEB ADDRESS; HTTP//MAPMASON.CO.MASON.WA.US/WEBS ITE/MASON. SCALE IN FEET 2. EARTH MATERIAL DISPOSAL SITE, MASON COUNTY GRADING PERMIT GRD-99-00009. 3. THE EXISTING DISTURBANCE AREA(APPROX. 4 ACRES)AT THE TIME OF APPLICATION WILL BE RECLAIMED CONTEMPORANEOUSLY WITH MINING OF SEGMENT 1,ALTHOUGH THIS AREA IS WITHIN RECLAMATION PHASE 5. S MASON-WA'COUNTY-PROJECTS 1 744-HAMA HAMA COMPANY 1 744 01-HAMA HAMA PIT 1744.01 -FIGURES\1744.01 -VM-AP--EX-RS-FL.DWG 1 ST PHASE OPEN AREA WITH TEMPORARY INFILTRATION LEGEND: ♦ PO D(5.0 ACRES-GRAVEL) INING M-1 AREA LEFT . . PROPERTY BOUNDARY } UNP TURBED UNTIL NEEDED. `` --/' ' - —• - - __ �� �� � � �� � ,\ PERMIT BOUNDARY g (183 ACRES) aLLJ 3 �} 5 ACRE_TC PATHWAY: (D 3 1 _ - GRASSEDOVERLANQ=5kFT` ♦ SETBACK (� 11 ACRES) Q c (" \ - / Z �.O -- L fH 52`5 FT , �, �.r �' �250' _ c m C _ . v __ ; , •_ SL{QPE=A. %- _ EXISTING TOPOGRAPHY a N a I (100' INTERVALS) Z ° z cc CN - 1 `.1 .. ;•; __-��� EXISTING TOPOGRAPHY IZ < (20' INTERVALS) = 0 FINAL TOPOGRAPHY (100' INTERVALS) a =C r- 1--` — —��• ��' �' \\\ t 1 tl t f R-5 FINAL TOPOGRAPHY (20 INTERVALS) c I \ a-135 \ORES) _ 1 \ 1, 0 t t \l, CROSS SECTION LOCATION J ,I I SEE FIGURE 6 111 WETLANDilk s M-2 �I \`�\ \ _ — — — _ 250'WETLAND BUFFER R-1 \ t 28 27 GEOREFERENCE (SECTION CORNER) W FILTR POND 33 1 34 FINAL M1 BICIS L M-3 (SEE POND D ► R CONSTR. R-2 TAILS)/ i l /r 1 EARTH MATERIAL DISPOSAL SITE o (SEE NOTE 2) u oVe 135 A('RESI -_ ,_ WELL m x 0 c LIJ (31ACRES --___ (3SACRESI ---__ , f--- DRAINAGE PATTERNS 1 FINAL < � , / N . .• ,\ ; 'Y•,•: ..• ; .�• EXAMPLE OPEN MINING 8 SORTING 28 i7_,,' 3ar AREA '8h U�TIMA�E TC PATHWAY: 1 GRASSEb OVERLAND=100 T !, ,l r„ , / EXISTING BASIN �t ®$LOVE`=26.496 _ BOUNDARY `_ ; ,';,',p I', i EX.AREA= 179 ACR INFILTRATION POND �N GRAVEL DITCH= 11�64)'T , / r o� N QSLOPE 0.391) � +� O lu 0 U. i A 600 1200 \ NOTES: PR. TIME OF CONCENTRATION PATH 1. BASE MAP&TOPOGRAPHY OBTAINED ONLINE FROM MASON COUNTY ASSESSOR AT WEB ADDRESS; SCALE IN FEET HTTP//MAPMASON.CO.MASON.WA.USNVEBSITEIMASON. 2. EARTH MATERIAL DISPOSAL SITE,MASON COUNTY GRADING PERMIT GRD-99-00009. %!AS(-;N 'dVAk,COUNTY-PROJECTS\1 744 HAMA HAMA COMPANY 1744.01-HAMA HAMA PIT 1 744.01-FIGURES\1 744.01-VM-AP--EX-RS-FL.DWG 0 40 80 BIOSWALE: 100LF 00.50% / I 0 HOR: SCALE IN FEET 0 10 20 - 299.0 IE=299.0 N N9 16LF 2"CMP 01 .75% VERT: SCALE IN FEET 299 25 �^^��� _ IE=296. ( I ( 0.5' 3' 10' 3' 0.5' ROCK UTFA I I I BERM BERM - �•••�"'9 5'W x 'DEEP j ' 2 294 292 \ . I 4"-8" FRACTURtD RO�K EXIST GRADE MAINTENANCE EXTEND�TO TOE OF SLOPE ACCESS RAMP: 29 1 -.6 \ \ ^� O 6"CSTC 1 c v! I \ M. m cE N� \ � � U �?.. B INFILTRATION ►� \ \ �p= E �`" POND r 1 TYPICAL BIOSWALE SECTION u- I)! ME = o NTS cc c° U 118 ch= E � 3 5'R MATCH *XISTING 300t = on� rJ BOTTOM=288.0 P� I ) \ Iz> ms N � a N TY �. GRADE\ p CR1mpm » >rssCOs 40'!C 90% 90x c • ` PSOXIQQAL Ru ws 96x 9m O / I OOY= Tm S RITH TOPS. On Nuun NO Dl�1ot TB�M IIiCH. !! }S B1C!l10t fO � 290 292 I w0>�[ TOPsoIQ, nrro Tss vPPa solo X&TM. uxa > Taar s> n • uY>!sz or a CO 2g4 � ' >roLc°��MW= i WAY MW IN UM APPLicAaorf8 w1Ta APPIovID - _ _ _ - - - _ � _ N 43 ACRL — — — 1 100 YEAR ELEV=298.0 i POND PLAW I Q � o � tt cm tA [-6 MIN BERM EXIST GRADE ---}-BI SWALE EXIST GRADE 'MIN BERM x � w 2 in 300 300 300 300 v Y a c 100 YEAR E EV=298.0 100 YEkR ELEV=29 .0 Q uw w = a cr DOwa0Qa `�S PROPOSED Ile S: PROPOS DIle �L POND �G POND 290 290 290 290 � 0TTOM=288 BOTTOM 288.0 FG FG 9 $ POND SCALE 1 w=40' HOR POND SCALE: 1*-40' HOR @c ju R SECTION A—A 1 =10 VERT SECTION B—B 1 10 vERT 1 3 I NOTES: gill 1. BASE MAP&TOPOGRAPHY OBTAINED ONLINE FROM MASON COUNTY ASSESSOR AT WEB ADDRESS; b HTTP://MAPMASON.CO.MASON.WA.USNVEBSITE/MASON. 2. EARTH MATERIAL DISPOSAL SITE;MASON COUNTY GRADING PERMIT GRD-99-00009.