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Drainage and Erosion ControlOUR REDEEMER FAITH LUTHERAN CHURCH Preliminary Drainage and Erosion Control Report Prepared for: Trans Northwest Construction Inc. 8625 Bedington Dr SE Olympia, WA 98513 (360) 413-0195 November 22, 2005 Prepared by: David W Spitler, P.E. Reviewed by: Steven D. Hatton, PE HATTON GODAT PANTIER 1840 Barnes Blvd SW Tumwater, WA 98512 (360) 943-1599 Project No: 05-079 Project Name: OUR REDEEMER FAITH LUTHERAN CHURCH E:lofficelJOBS12005105-0791RPT-Drainage-11.22.05.doc TABLE OF CONTENTS I. PROJECT ENGINEER'S CERTIFICATE ............................................................................... 3 II. THURSTON REGION FACILITY SUMMARY FORM ............................................................ 4 III. THURSTON REGION FACILITY SUMMARY FORM ............................................................ 4 IV. DRAINAGE REPORT ............................................................................................................ 12 Section 1 -Project Description ................................................................................... 12 Section 2 -Existing Conditions ................................................................................... 12 Section 3 -Soils Report .............................................................................................. 12 Section 4 -Wells and Septic Systems ........................................................................ 13 Section 5 -Fuel Tanks ................................................................................................ 13 Section 6 -Sub-basin Description .............................................................................. 13 Section 7-Analysis of 100-Year Flood ....................................................................... 13 Section 8 -Aesthetic Considerations ......................................................................... 13 Section 9 -Facility Sizing and Downstream Analysis ................................................. 13 Section 10 -Covenants, Dedications, and Easements .............................................. 14 Section 11 -Articles of Incorporation ......................................................................... 14 V. EROSION CONTROL PLAN ................................................................................................. 15 Section 1 -Construction Sequence ............................................................................ 15 Section 2 -Trapping Sediment ................................................................................... 15 Section 3 -Site Restoration ........................................................................................ 16 Section 4 - Geotechnical Analysis .............................................................................. 16 Section 5 -Inspection Sequence ................................................................................ 16 Section 6 -Control of Pollutants other than Sediments ............................................. 16 VI. STORMWATER MAINTENANCE PLAN ............................................................................. 17 Appendix A -Soils Report Appendix B -Wet Vault Sizing Calculations Appendix C -Infiltration Sizing Calculations I. PROJECT ENGINEER'S CERTIFICATE I hereby certify that this Drainage and Erosion Control Report for OUR REDEEMER FAITH LUTHERAN CHURCH, 805 YELM AVENUE, CITY OF YELM, Washington, has been prepared by me or under my direct supervision and meets minimum standards of CITY OF YELM and normal standards of engineering practice. I understand that the jurisdiction does not and will not assume liability for the sufficiency, suitability, or performance of drainage facilities designed by me. f ~~y/~~ L~~Z~!G~ Signature I ~ 3~~c'S Date C~v Seal OUR REDEEMER FRITH LUTHER/1N CHURCH 11.22.05 PAGE 3 II. THURSTON REGION FACILITY SUMMARY FORM Complete one for each facility (detention/retention, coalescing plate filter, etc.) on the project site. Attach 8%2 " by 11"sketch showing location of facility. Proponent's facility name or identifier (e.g., Pond A): Name of road or street to access facility: Hearings Examiner case number: Development Review Project No. /Bldg. Permit No.: Parcel Number(s): On-site Yelm Avenue 22730121100 To Be Completed By Utility Staff: Utility facility number :.................................................... Parcel number status, (num, 1ch) .......................... 0-Known; 1-Public; 2-Unknown; 3-Unassigned Basin and sub-basin, (num, 6ch) ............................ (2ch-Basin; 2ch-Sub-basin; 2ch-Future Responsible jurisdiction, (alpha, 1ch) ..................... O-Olympia; C-County; T-Tumwater; L-Lacey Part 1 - Proiect Name and Proponent Project name: Project owner: Project contact: Address: Phone: Project proponent (if different): Address: Phone: Project engineer: Firm: Phone number: OUR REDEEMER FAITH LUTHERAN CHURCH Our Redeemer Lutheran Church Nate Radichel 805 Yelm Ave E Yelm, WA 98597 Trans Northwest Construction Inc. (Mike Opitz) 8625 Bedington Drive SE Olympia, WA 98513 (3601 413-0195 Steven D. Hatton, PE HATTON GODAT PANTIER (360) 943-1599 OUR REDEEtv1ER rAITH LUTHERAN CHURCH 11.22.05 PAGE ~1 Part 2 - Project Location Section .......................... Township ...................... 30 17N Range .............................. 2E Names and addresses of adjacent property owners: YELM CAPITAL 717 YELM AVE YELM, WA 98597 ENTERPRISES LLC GLEN L NUTTER 10422 CLARK RD SE YELM, WA 98597 SCOTT DEMICH PO BOX 577 YELM, WA 98597 GREG J & AMY L DOMGARD PO BOX 2406 YELM, WA 98597 CARL B CASSADY 2235 HIDDEN ACRES RD MEADOW VISTA, CA 95722 EAR ENTERPRISES PO BOX 875 YELM, WA 98597 BILL & JEANNIE HERTEL 10101 SE 270T" PL KENT, WA 98031 JOHN F & TERESA F VOTRUBA PO BOX 3165 HARRISBURG, PA 17105 Part 3 - Type of Permit Application Type of permit (e.g., commercial building): Other permits (D): ^ DOF NV HPA ^ COE Wetlands ^ FEMA ^ Shoreline Management ® Encroachment ^ Other Commercial Buildi ^ COE 404 ^ DOE Dam Safety ^ Floodplain ^ Rockery/Retaining Wall ® Grading Other agencies (Federal, State, Local, etc.) that have or will review this Drainage and Erosion Control Plan: NONE C?UR RECEEMER FAITH LUTHERAN CHURCH 11.22.05 PAGE 5 Part 4 -Proposed Project Description What stream basin is the project in (e.g., Percival, Woodland, etc.)? Nisqually River Zoning :........................ Commercial C-1 On-site: Residential Subdivision: Number of lots .......................................................... Lot size (average, acres) .......................................... Building Permit/Commercial Plat: Building(s) (footprint, acres) ..................................... Concrete paving (acres) ........................................... Gravel surface (acres) .............................................. Lattice block paving (acres) ...................................... Public roads-including gravel shoulder (acres) ........ Private roads-including gravel shoulder (acres) ....... On-site impervious surface total (acres) .................... Part 5 -Pre-developed Proiect Site Characteristics: Stream through site (y/n) ..................................... NO Name ............................................. N/A DNR Type ..................................... NIA 0.09 0.33 0.35 0.77 Type of feature this facility discharges to (i.e., lake, stream, intermittent stream, pothole, roadside ditch, sheetflow to adjacent property, etc.): ENTER TYPE OF DISCHARGE HERE Swales (y/n) ............................................................ N Steep slopes-steeper than 10% (y/n) ..................... N Erosion hazard (y/n) ................................................ N 100-year floodplain (y/n) ......................................... N Wetlands (y/n) ......................................................... N Seeps/springs (y/n) ................................................. N High groundwater table (y/n) .................................. N Other Description ................................................. N OUR REDEEMER FAITH LUTHERAN CHURCH 11.22.05 PAGE 6 Part 6 -Facility Description Total area tributary to facility including off-site (acres) ................... 0.44 Total on-site area tributary to facility (acres) ................................... 0.44 Design impervious area tributary to facility (acres) ......................... 0.44 Design landscaped area tributary to facility (acres) ........................ 0.00 Design total tributary area to facility (acres) ................................... 0.44 Enter "1"for type of facility: Wet pond detention ................................................. Wet pond water surface area (acres) ..................... Dry pond detention .................................................. Underground detention ........................................... Infiltration pond ....................................................... Drywell infiltration .................................................... Coalescing plate separator ..................................... Centrifuge separator ............................................... Other Wet Tank ..................................................... 1 Outlet type (enter "1" for each type present): Filter ........................................................................ Oil/water separator .................................................. Single orifice ........................................................... Multiple orifices ....................................................... Weir ......................................................................... Spillway ................................................................... Pump(s) .................................................................. Other Underground Infiltration ........................... 1 Part 7 -Release to Groundwater Design percolation rate to groundwater (if applicable) ........................ 20 inches per hour Part 8 -Release to Surface Water (if applicable) Thurston County MSL Percent Design Discharge To Surface Elevation ft. Full Volume cu. ft. Water cfs 0 0.00 0.00 25 50 100 C?UR REDEEE4IER FAITH LUTHERAN CHURCH 11.22.05 PAGE 7 III. THURSTON REGION FACILITY SUMMARY FORM Complete one for each facility (detention/retention, coalescing plate filter, etc.) on the project site. Attach 8%2 " by 11"sketch showing location of facility. Proponent's facility name or identifier (e.g., Pond A): Name of road or street to access facility: Hearings Examiner case number:. Development Review Project No. /Bldg. Permit No.: Parcel Number(s): Access Road Yelm Avenue 22730121100 To Be Completed By Utility Staff: Utility facility number :........................................................ Parcel number status, (num, 1 ch) .................................... 0-Known; 1-Public; 2-Unknown; 3-Unassigned Basin and sub-basin, (num, 6ch) ...................................... (2ch-Basin; 2ch-Sub-basin; 2ch-Future Responsible jurisdiction, (alpha, 1ch) ............................... O-Olympia; C-County; T-Tumwater; L-Lacey Part 1 - Proiect Name and Proponent Project name: OUR REDEEMER FAITH LUTHERAN CHURCH Project owner: Our Redeemer Lutheran Church Project contact: Nate Radichel Address: 805 Yelm Ave E, Yelm, WA 98597 Phone: Project proponent (if different): .Trans Northwest Construction Inc. (Mike Opitz) Address: 8625 Bedington Drive SE, Olympia, WA 98513 Phone: (360) 413-0195 Project engineer: Steven D. Hatton, PE Firm: HATTON GODAT PANTIER Phone number: (360) 943-1599 OUR REDEEMER FAITH LUTHERAN GHURGH 11.22.Q5 PAGE 8 Part 2 - Project Location Section .......... Township ...... Range ........... 30 17N 2E Names and addresses of adjacent property owners: YELM CAPITAL 717 YELM AVE YELM, WA 98597 ENTERPRISES LLC GLEN L NUTTER 10422 CLARK RD SE YELM, WA 98597 SCOTT DEMICH PO BOX 577 YELM, WA 98597 GREG J & AMY L DOMGARD PO BOX 2406 YELM, WA 98597 CARL B CASSADY 2235 HIDDEN ACRES RD MEADOW VISTA, CA 95722 EAR ENTERPRISES PO BOX 875 YELM, WA 98597 BILL & JEANNIE HERTEL 10101 SE 270T" PL KENT, WA 98031 JOHN F & TERESA F VOTRUBA PO BOX 3165 HARRISBURG, PA 17105 Part 3 - Tvpe of Permit Application Type of permit (e.g., commercial building): Other permits (^D ): ^ DOF NV HPA ^ COE Wetlands ^ FEMA ^ Shoreline Management ® Encroachment ^ Other Commercial Building ^ COE 404 ^ DOE Dam Safety ^ Floodplain ^ Rockery/Retaining Wall ® Grading Other agencies (Federal, State, Local, etc.) that have or will review this Drainage and Erosion Control Plan: NONE OUR f2EC?cc(49cFZ FAITH LUTHEF2AN CHURCH 11.22.05 PAGE 9 Part 4 -Proposed Project Description What stream basin is the project in (e.g., Percival, Woodland, etc.)? Zoning :........................ Commercial C-1 On-site: Residential Subdivision: Number of lots .......................................................... Lot size (average, acres) .......................................... Building Permit/Commercial Plat: Building(s) (footprint, acres) ..................................... Concrete paving (acres) ........................................... Gravel surface (acres) .............................................. Lattice block paving (acres) ...................................... Public roads-including gravel shoulder (acres) ........ Private roads-including gravel shoulder (acres) ....... On-site impervious surface total (acres) .................... Part 5 -Pre-developed Proiect Site Characteristics: Stream through site (y/n) ..................................... NO 0.77 Name ............................................. NIA DNR Type ..................................... NIA Type of feature this facility discharges to (i.e., lake, stream, intermittent stream, pothole, roadside ditch, sheetflow to adjacent property, etc.): ENTER TYPE OF DISCHARGE HERE Swales (y/n) ............................................................ N Steep slopes-steeper than 10% (y/n) ..................... N Erosion hazard (y/n) ................................................ N 100-year floodplain (y/n) ......................................... N Wetlands (y/n) ......................................................... N Seeps/springs (y/n) ................................................. N High groundwater table (y/n) .................................. N Other Description ................................................. N Nisqually River 0.09 0.33 0.35 OUR REDEEMER FAITH LUTHERAN CHURCH 11.22.05 PAGE 10 Part 6 -Facility Description Total area tributary to facility including off-site (acres) ................... Total on-site area tributary to facility (acres) ................................... Design impervious area tributary to facility (acres) ......................... Design landscaped area tributary to facility (acres) ........................ Design total tributary area to facility (acres) ................................... Enter "1" for type of facility: Wet pond detention ................................................. Wet pond water surface area (acres) ..................... Dry pond detention .................................................. Underground detention ........................................... Infiltration pond ....................................................... Drywell infiltration .................................................... Coalescing plate separator ..................................... Centrifuge separator ............................................... Other Wet Tank ..................................................... 1 Outlet type (enter "1"for each type present): Filter Oil/water separator .................................................. Single orifice ........................................................... Multiple orifices ....................................................... Weir ......................................................................... Spillway ................................................................... Pump(s) .................................................................. Other Underground Infiltration ........................... 1 Part 7 -Release to Groundwater 0.51 0.00 0.51 0.00 0.51 Design percolation rate to groundwater (if applicable) ........................ 20 inches per hour Part 8 -Release to Surface Water (if applicable) Thurston County MSL Percent Design Discharge To Surface Elevation ft. Full Volume cu. ft. Water cfs 0 0.00 0.00 25 50 100 t~UP. REC?EEMER FAITH LUTHERAN CHURCH 11.22A5 PAGE 11 IV. DRAINAGE REPORT Section 1 -Project Description This proposal seeks approval to construct a 3,840 sf car wash building with associated parking and drive facilities on 0.57 acres. The site is located south of the intersection of Yelm Avenue (SR 507) and 103` Avenue, parcel number 21724130700. The site is zoned commercial (C1), which allows the use. The project consists of onsite parking, drive, and building with improvements to Yelm Avenue. Stormwater improvements will be provided onsite for the project. City water and sewer service is available at the site and is proposed to service the site. The project will require site plan approval, grading and building perm its. Stormwater Best Management Practices will be provided for the project, including two wet vaults to treat run-off. These facilities will treat the 6-month event. Storm water quality runoff impacts are mitigated by a non-site infiltration pond. The building runofff will be infiltrated in a drywell. These facilities are designed to infiltrate the 100-year event. Appendix B contains a reduced copy of the site plan. Description On-site Access Road Impervious Area (ac) Total Area (ac) Roof Area (drains to separate dry well system) 0.33 0.44 0.35 0.51 0.07 0.07 Site Total 0.75 1.02 NOTE: For preliminary sizing all calculations assume 100% impervious areas Section 2 -Existing Conditions There is no significant offsite drainage tributary to the site. Yelm Highway appears to infiltrate in road side swales. The Rite Aid site, located east of the site, has an on-site storm water collection and infiltration system. The parcels south of the site drain to an infiltration pond, and the parcels west of the site drain away from the site. The site generally drains to the southwest at a maximum grade of 2%. The site is located within an aquifer recharge area.. There are no known creeks, lakes, ponds, wetlands, gullies, steep slopes, spring or other environmentally sensitive area on site or immediately down gradient of the property. Section 3 -Soils Report The Thurston County Soils map list the soils on the site as Spanaway gravelly sandy loam. Infiltration rates for Spanaway soils generally considered rapid. Testing by Pacific Rim Soil and Water has shown infiltration rates above 50 inches per hour. However, the report recommends an infiltration rate of 20 in/hr QUR REQEEMER FAITH LUTHERAN CHURCH 11.22.05 PAGE 12 for design, to account for construction activities. A copy of the soil report by Pacific Rim Soil and Water is included in Appendix A. Based on the report by Pacific Rim Soil and Water, the design infiltration rate is 20 in/hr. Section 4 -Wells and Septic Systems Records at Thurston County and the Department of Ecology were searched in order to locate wells and septic systems that may be located within the setback distances from the stormwater pond or ponds. In addition, the Project Engineer, or someone under his direct supervision, has visited the site to verify the presence or absence of wells and septic systems as best can be done visually without trespassing onto other properties. All wells and septic systems found to be located within the setback distances from the stormwater pond or ponds have been shown on the plans. Section 5 -Fuel Tanks Records at Thurston County and the Department of Ecology were searched in order to locate the presence of above and below ground fuel storage tanks that may be located within the setback distances from the stormwater pond or ponds. In addition, the Project Engineer, or someone under his direct supervision, has visited the site to verify the presence or absence of fuel tanks as best can be done visually without trespassing onto other properties. All fuel tanks found to be located within the setback distances from the stormwater pond or ponds have been shown on the plans. Section 6 -Sub-basin Description Section 7- Analysis of 100-Year Flood The Federal Emergency Management Agency prepares maps for all areas within Thurston County, including the incorporated cities therein. Panel # 50310-0001 A depicts the areas, if any, subjected to flooding in the vicinity of this proposal. By inspection of this map, this proposal appears to be located in Zone C, an area of minimal flooding. This area, therefore, is not located within the 100-year flood plain. Section 8 -Aesthetic Considerations All above ground stormwater facilities will be hydroseeded upon completion. In addition, the water quality wet pond will be planted with a variety of wetland species both in the permanent pool and along the fringes of the permanent water surface. Additional landscaping shall also be provided throughout the project in conformance with the approved landscaping and tree restoration plan, as applicable, and as otherwise required by the approving authority. Section 9 -Facility Sizing and Downstream Analysis This project has been designed per the requirements of the Storm Water Management Manual for the Puget Sound Basin published in 1992 that has been developed by the Washington State Department of Ecology. The storm water conveyance system and drainage control features have been analyzed using the HYDRA computer modeling software that utilizes the SCS SBUH method. Infiltration Trench Sizing Calculations: The flow out of the infiltration trench was calculated based on the design infiltration rate of 20 in/hr over the bottom area of the infiltration trench. The plans propose a total of 70 LF on-site and 90 LF for the access road, of 5-foot wide trench with 12-inch perforated pipe. OUR REDEEi4~iER FAI T H LUTHERAN CHURuH 11.22.05 PAGE 1s Qo„t (on-site) = 70 ft * 20 in/hr * ft/12-in * hr/3600 sec = 0.16 cfs Qo„t (access road) = 80 ft * 5 ft * 20 in/hr * ft/12-in * hr/3600 sec =0.19 cfs The runoff contributing to the on-site system was modeled using the Hydra ®Computer Program. The program uses Soil Conversation Unit Hydrograph methods to calculate runoff contributing to each catch basin and routes the resulting hydrograph through a model of the infiltration system. An Excel wet vault above the dead storage volume; both are included in Appendix C. The computer analysis indicated that the system would contain and infiltrate the 24-hour 100-year event with in the system. Copies of the computer printouts are provided in Appendix C. Infiltration Svstem Specifics Dimensions: On-site Access Road Length 70 LF 80 LF Trench Width 5 feet 5 feet PerForated Pipe 12-inch 12-inch Computer Analysis 100-year 24-hour event Volume 487 CF 549 CF Elevation + 4.5 feet + 4.5 feet Wet Vault Sizing: The drainage manual standard is a pond with a permanent pool depth of 3-6 feet deep with the volume of the 6-month, 24-hour rainfall event. The contributing area for the pond consists of 0.98 ac of impervious parking lot. Section 10 -Covenants, Dedications, and Easements All stormwater facilities located on private property shall be owned, operated, and maintained by the property owners, their heirs, successors, and assigns. The property owners shall enter into an agreement with the governing body, a copy of which is included in Part V of this report. The agreement requires maintenance of the stormwater facilities in accordance with the maintenance plan provided and shall grant easement for access to the governing body to inspect the stormwater facilities. The agreement also makes provisions for the governing body to make repairs, after due notice is given to the owners, if repairs are necessary to ensure proper performance of the stormwater system and if the owners fail to make the necessary repairs. The cost of said repairs shall be borne by the property owners, their heirs, successors, and assigns. Section 11 -Articles of Incorporation All residential subdivisions shall form a Homeowner's Association for the purpose of assigning responsibility and liability for the operation and maintenance of stormwater facilities jointly serving lots within the subdivision. The association is not required for facilities that serve a single property owner. Articles of Incorporation shall be developed for the association and submitted to the governing body prior to final project approval. QUR REDEEMER FAITH LUTHERAN CHURCH 11.22.45 PAGE 14 V. EROSION CONTROL PLAN Section 1 -Construction Sequence Prior to commencing any grading or filling upon the site, all erosion control measures, including installation of a stabilized construction entrance, shall be installed in accordance with this plan and the details shown on the drawings. More specifically, the following construction sequence shall be observed: Construction on this site shall be conducted substantially in accordance with the construction sequence described on the plans and in this erosion control plan. Deviations from this sequence shall be submitted to the project engineer and permitting jurisdiction. Deviations must be approved prior to any site disturbing activity not contained within these plans. 2. For each phase of the development of this site, the following general sequence shall be observed: a. Install perimeter filter fabric fence as shown. b. Install inlet protection for existing inlets in the vicinity of areas to be disturbed. c. Call for inspection by the project engineer. d. Construct temporary sedimentation trap(s) and outlet(s). e. Perform grading directing site runoff towards the sediment trap prior to discharge from the site. f. Install temporary piping, as required, to direct runoff towards the sediment trap. 3. Once the site is disturbed, continue operations diligently toward completion. 4. Monitor all erosion control facilities, and repair, modify, or enhance as directed or as required. Section 2 -Trapping Sediment Sediment ponds shall be constructed at the beginning of each phase of construction to perform as temporary sediment traps. Protection of offsite properties against sedimentation is an absolute necessity. Additional measures may be required to provide full protection of downstream areas. Additional measures may include, but are not limited to, use of sediment bags in existing catch basins, increased filters within sediment ponds such as hay bales, introduction of coagulants to the sediment ponds, and other such measures. Continuous monitoring of the erosion control systems, depending upon site and weather conditions, shall be ongoing throughout project development. Vehicle tracking of mud off-site shall be avoided. Installation of a stabilized construction entrance shall be installed at the start of construction at the exit point to be used by equipment. This entrance is a minimum requirement and may be supplemented if tracking of mud onto public rights-of-way becomes excessive. Washing down roads daily to remove excessive mud may be required. Wash water shall be directed to the temporary sediment traps installed on-site and shall not be allowed to discharge downstream without treatment. OUR REDEEMER FAITH LUTHERAN CHURCH 11.22.05 PAGE 15 Section 3 -Site- Restoration Disturbed areas on and off-site shall be hydroseeded or otherwise landscaped or stabilized upon project completion to provide permanent erosion control where required. Erosion control measures shall remain in place until final site stabilization is imminent (e.g., paving scheduled with a favorable weather forecast). Section 4 - Geotechnical Analysis Existing slopes in the area of the stormwater ponds are at a maximum of 2%. The temporary sediment ponds will be excavated into the native soil. No embankment is required. Section 5 -Inspection Sequence The Project Engineer, or someone under his direct supervision, and the permit authority shall inspect the temporary erosion control facilities (construction entrance, sediment traps, and erosion control barriers) prior to commencement of construction. During and following construction, the Engineer shall inspect the construction of the permanent stormwater facilities and report to the permit authority his findings as to performance and operability of the completed system. Section 6 -Control of Pollutants other than Sediments A centralized equipment marshalling area and containment area is to be provided on-site for equipment maintenance and storage of any equipment service materials. An area on-site will be selected as a temporary debris and stockpile area for materials that will be removed from the site. Erosion control containment and berming of this area will be provided for pollutant containment and sheeting provided for coverage or lining if applicable. bUR REDEEMER FAITH LUTHERAN CHURCH 11.22.Q~ PAGE 16 VI. STORMWATER MAINTENANCE PLAN OUR REDEEMER FAITH LUTHERAN CHURCH NOVEMBER 22, 2005 OUR REDEEIL~IER FAITH LUTr{ERAN CHURCH 11.22A5 r ACE 17 TABLE OF CONTENTS MAINTENANCE AGREEMENT ..........................................................................................................19 II. STORMWATER FACILITY MAINTENANCE GUIDE ........................................................................ 20 INTRODUCTION ........................................................................................................................... 20 What is Stormwater Runoff? .................................................................................................... 20 What is a Storm Drain System and how does it work? ............................................................ 20 What does Stormwater Runoff have to do with Water Quality? ............................................... 20 Your Stormwater Facility .......................................................................................................... 20 Who is Responsible for Maintaining Stormwater Facilities? .................................................... 20 How to Use the Stormwater Facility Maintenance Guide ......................................................... 21 Included in This Guide .............................................................................................................. 21 A Regional Approach to Stormwater Management .........:........................................................ 21 YOUR STORMWATER FACILITIES ............................................................................................. 21 FACILITY KEY ............................................................................................................................... 21 SITE PLAN .................................................................................................................................... 22 QUICK LIST ................................................................................................................................... 23 MAINTENANCE CHECKLISTS ..................................................................................................... 24 Infiltration Trench ...................................................................................................................... 25 Catch Basins, Manholes, and Inlets ......................................................................................... 26 Fencing, Shrubbery Screens, and Gates ................................................................................. 27 Conveyance Pipes, Ditches, and Swales ................................................................................. 28 Grounds and Landscaping ....................................................................................................... 29 Treatment Vault ........................................................................................................................ 30 Drywells, French Drains, or Downspouts ................................................................................. 31 RESOURCE LISTING .........................:......................................................................................... 32 III. POLLUTION SOURCE CONTROL PROGRAM ................................................................................ 34 What Are Pollution Source Controls And Why Are They Needed? .......................................... 34 Materials Used And Wastes Generated ................................................................................... 34 Required Actions ...................................................................................................................... 34 Return to: Thurston County Storm & Surface Water 2000 Lakeridge Dr. SW Olympia, WA 98502 COMMERCIAL/INDUSTRIAL AGREEMENT TO MAINTAIN STORMWATER FACILITIES AND TO IMPLEMENT A POLLUTION SOURCE CONTROL PLAN BY AND BETWEEN THURSTON COUNTY (HEREINAFTER "JURISDICTION") AND OUR REDEEMER FAITH LUTHERAN CHURCH ITS HEIRS, SUCCESSORS, OR ASSIGNS (HEREINAFTER "OUR REDEEMER FAITH LUTHERAN CHURCH") GRANTOR: CHURCH, OUR REDEEMER FAITH LUTHERAN GRANTEE: THURSTON, COUNTY OF LEGAL DESCRIPTION: Section 30, Township 17 North, Range 2 East ASSESSOR'S TAX PARCEL NO.: 22730121100 The upkeep and maintenance of stormwater facilities and the implementation of pollution source control best management practices (BMPs) is essential to the protection of water resources. All property owners are expected to conduct business in a manner that promotes environmental protection. This Agreement contains specific provisions with respect to maintenance of stormwater facilities and use of pollution source control BMPs. LEGAL DESCRIPTION: Section 30, Township 17 North, Range 2 East Whereas, OUR REDEEMER FAITH LUTHERAN CHURCH has constructed improvements, including but not limited to, buildings,. pavement, and stormwater facilities on the property described above. In order to further the goals of the Jurisdiction to ensure the protection and enhancement of Jurisdiction's water resources, the Jurisdiction and OUR REDEEMER FAITH LUTHERAN CHURCH hereby enter into this Agreement. The responsibilities of each party to this Agreement are identified below. OUR REDEEMER FAITH LUTHERAN CHURCH SHALL: (1) Implement the stormwater facility maintenance program included herein as Attachment ..A „ (2) Implement the pollution source control program included herein as Attachment "B". (3) Maintain a record (in the form of a log book) of steps taken to implement the programs referenced in (1) and (2) above. The log book shall be available for inspection by Jurisdiction staff at 805 Yelm Avenue E, Yelm, WA 98597 during normal business hours. The log book shall catalog the action taken, who took it, when it was done, how it was done, and any problems encountered or follow-on actions recommended. Maintenance items ("problems") listed in Attachment "A" shall be inspected on a monthly or more frequent basis as necessary. OUR REDEEMER FAITH LUTHERAN CHURCH is encouraged to photocopy the individual checklists in Attachment "A" and use them to complete its monthly inspections. These completed checklists would then, in combination, comprise the monthly log book. (4) Submit an annual report to the Jurisdiction regarding implementation of the programs referenced in (1) and (2) above. The report must be submitted on or before May 15 of each calendar year and shall contain, at a minimum, the following: (a) Name, address, and telephone number of the business, the person, or the firm responsible for plan implementation, and the person completing the report. (b) Time period covered by the report. (c) A chronological summary of activities conducted to implement the programs referenced in (1) and (2) above. A photocopy of the applicable sections of the log book, with any additional explanation needed, shall normally suffice. For any activities conducted by paid parties not affiliated with OUR REDEEMER FAITH LUTHERAN CHURCH, include a copy of the invoice for services. (d) An outline of planned activities for the next year. THE JURISDICTION SHALL: (1) Provide technical assistance to OUR REDEEMER FAITH LUTHERAN CHURCH in support of its operation and maintenance activities conducted pursuant to its maintenance and source control programs. Said assistance shall be provided upon request and as Jurisdiction time and resources permit, at no charge to OUR REDEEMER FAITH LUTHERAN CHURCH. (2) Review the annual report and conduct a minimum of one (1) site visit per year to discuss performance and problems with OUR REDEEMER FAITH LUTHERAN CHURCH. (3) Review this agreement with OUR REDEEMER FAITH LUTHERAN CHURCH and modify it as necessary at least once every three (3) years. REMEDIES: (1) If the Jurisdiction determines that maintenance or repair work is required to be done to the stormwater facility existing on the OUR REDEEMER FAITH LUTHERAN CHURCH property, the Jurisdiction shall give the owner of the property within which the drainage facility is located, and the person or agent in control of said property, notice of the specific maintenance and/or repair required. The Jurisdiction shall set a reasonable time in which such work is to be completed by the persons who were given notice. If the above required maintenance and/or repair is not completed within the time set by the Jurisdiction, written notice will be sent to the persons who were given notice stating the Jurisdiction's intention to perform such maintenance and bill the owner for all incurred expenses. The Jurisdiction may also revoke stormwater utility rate credits for the quality component or invoke surcharges to the quantity component of the OUR REDEEMER FAITH LUTHERAN CHURCH bill if required maintenance is not performed. (2) If at any time the Jurisdiction determines that the existing system creates any imminent threat to public health or welfare, the Jurisdiction may take immediate measures to remedy said threat. No notice to the persons listed in (1 ), above, shall be required under such circumstances. (3) The owner grants unrestricted authority to the Jurisdiction for access to any and all stormwater system features for the purpose of performing maintenance or repair as may become necessary under Remedies (1) and/or (2). (4) The persons listed in (1 ), above, shall assume responsibility for the cost of any maintenance and for repairs to the stormwater facility. Such responsibility shall include reimbursement to the Jurisdiction within 30 days of the receipt of the invoice for any such work performed. Overdue payments will require payment of interest at the current legal rate for liquidated judgments. If legal action ensues, any costs or fees incurred by the Jurisdiction will be borne by the parties responsible for said reimbursements. (5) The owner hereby grants to the Jurisdiction a lien against the above-described property in an amount equal to the cost incurred by the Jurisdiction to perform the maintenance or repair work described herein. This Agreement is intended to protect the value and desirability of the real property described above and to benefit all the citizens of the Jurisdiction. It shall run with the land and be binding on all parties having or acquiring from OUR REDEEMER FAITH LUTHERAN CHURCH or their successors any right, title, or interest in the property, or any part thereof, as well as their title, or interest in the property or any part thereof, as well as their heirs, successors, and assigns. They shall inure to the benefit of each present or future successor in interest of said property or any part thereof, or interest therein, and to the benefit of all citizens of the Jurisdiction. Owner Owner E:\office\agency\thurstonWPPENDIXK-COMstorm maintagr.doc STATE OF WASHINGTON ) ss COUNTY OF THURSTON ) On this day and year above personally appeared before me, and known to be the individual(s) described, and who executed the foregoing instrument and acknowledge that they signed the same as their free and voluntary act and deed for the uses and purposes therein mentioned. Given under my hand and official seal this day of , 200_. Notary Public in and for the State of Washington, residing in My commission expires Dated at ,Washington, this day of 200_ Thurston County STATE OF WASHINGTON ) ss COUNTY OF THURSTON ) On this day and year above personally appeared before me, who executed the foregoing instrument and acknowledge the said instrument to be the free and voluntary act and deed of said Municipal Corporation for the uses and purposes therein mentioned and on oath states he is authorized to execute the said instrument. Given under my hand and official seal this day of 200 Notary Public in and for the State of Washington, residing in My commission expires APPROVED AS TO FORM: II. STORMWATER FACILITY MAINTENANCE GUIDE INTRODUCTION What is Stormwater Runoff? When urban and suburban development covers the land with buildings, streets and parking lots, much of the native topsoil, duff, trees, shrubs and grass are replaced by asphalt and concrete. Rainfall that would have soaked directly into the ground instead stays on the surface as stormwater runoff making its way into storm drains (including man-made pipes, ditches, or swale networks), stormwater ponds, surface and groundwater, and eventually to Puget Sound. What is a Storm Drain System and how does it work? The storm drain system for most developments includes measures to carry, store, cleanse, and release the stormwater. Components work together to reduce the impacts of development on the environment. Impacts can include flooding which results in property damage and blocked emergency routes, erosion which can cause damage to salmon spawning habitat, and pollution which harms fish and/or drinking water supplies. The storm drain system provides a safe method to carry stormwater to the treatment and storage area. Swales and ponds filter pollutants from the stormwater by physically settling out particles, chemically binding pollutants to pond sediments, and biologically converting pollutants to less harmful compounds. Ponds also store treated water, releasing it gradually to a nearby stream or to groundwater. What does Stormwater Runoff have to do with Water Quality? Stormwater runoff must be treated because it carries litter, oil, gasoline, fertilizers, pesticides, pet wastes, sediments, and anything else that can float, dissolve or be swept along by moving water. Left untreated, polluted stormwater can reach nearby waterways where it can harm and even kill aquatic life. It can also pollute groundwater to the extent that it requires treatment before it is suitable for drinking. Nationally, stormwater is recognized as a major threat to water quality. Remember to keep everything out of stormwater systems except the rainwater they are designed to collect. Your Stormwater Facility Different types of ponds are designed for different purposes. For example, wet ponds primarily provide treatment of stormwater. Dry ponds or infiltration ponds are designed to provide storage for stormwater and allow for its gradual release downstream or into the ground. Who is Responsible for Maintaining Stormwater Facilities? All stormwater facilities require maintenance. Regular maintenance ensures proper functioning and preserves visual appeal. This Stormwater Facility Maintenance Guide was designed to explain how stormwater facilities work and provide user-friendly, straightforward guidance on facility maintenance. You are responsible for regularly maintaining privately owned ponds, catch basins, pipes and other drainage facilities on your property. Stormwater facilities located in public rights-of-way are maintained by local governments. OUR REDEEMER FAITH LUTHERAN CHURCH 11.22.45 PAGE 2D How to Use the Stormwater Facility Maintenance Guide This Maintenance Guide includes a Site Plan specific to your development and a Facility Key that identifies the private stormwater facilities you are responsible for maintaining. A "Quick List" of maintenance activities has also been included to help you identify the more routine needs of your facility. Included in This Guide ^ Comprehensive Maintenance Checklists that provide specific details on required maintenance ^ Pollution Prevention Tips that list ways to protect water quality and keep storm drain systems functioning smoothly ^ Resources to provide more information and technical assistance A Regional Approach to Stormwater Management The Cities of Lacey, Olympia and Tumwater together with Thurston County are taking steps to educate and involve area residents in water quality issues and stormwater management. Stormwater runoff is a widespread cause of water quality impairment and stream degradation. The jurisdictions are working together with residents, businesses, community groups and schools to address this problem. This guide focuses on providing information on ways that you can reduce stormwater impacts through pollution prevention and proper facility maintenance. YOUR STORMWATER FACILITIES This section consists of two parts that are to be used together: the Facility Key and the Site Plan. Review the site plan and identify the numbers denoting a feature of the system. Then check the facility key for the feature type and checklist name. FACILITY KEY The stormwater facility in your neighborhood is comprised of the following elements: Type of':Feature & Checklist Name Location on Site Plan Infiltration Trench 1 Catch Basins, Manholes, and Inlets 3 Fencing, Shrubbery Screens, and Gates 4 Conveyance Pipes, Ditches, and Swales 6 Grounds and Landscaping 7 Treatment Vault 12 Drywells, French Drains, or Downspouts See individual lot site plan. OUR REC?EEMER FAITH LUTHERAN GHURGH 11.22.05 PAGE 21 SITE PLAN OUR REDEEMER FAITH LUTHERAN CHURCH 11.22.05 PAGE 22 QUICK LIST The following is an abbreviated checklist of the most common types of maintenance required. Please go over this checklist after heavy rains. The list represents minimum maintenance to be performed and should be completed in conjunction with the other checklists for an effective maintenance program. ^ Inspect catch basin grates to see that they are not clogged or broken. Remove twigs, leaves, or other blockages. Contact the local jurisdiction to replace the grate if it is broken. ^ Inspect inlet and outlet pipes for blockages. Clear all blockages. ^ Inspect filter strip, swale and pond walls for erosion or caved in areas. ^ Inspect riprap (rocks) at the inlets and outlets of culverts and other pipes. If they are silted in or eroded away, replace them. QUR REC~EEMER FAITH LUTHERAN CHURCH 11.22.05 PAGE 23 MAINTENANCE CHECKLISTS The Maintenance Checklists in this packet are for your use when inspecting the stormwater facilities on your property. This packet has been customized so that only the checklists for your facilities are included. If you feel you are missing a checklist, or you have additional facilities not identified or addressed in this packet, please contact your local jurisdiction. The checklists are in tabular format for ease of use. Each describes the area to inspect, inspection frequency, what to look for, and what action to take. A log sheet is included toward the end of the chapter to help you track maintenance of your storm drainage system. Although it is not intended for the maintenance survey to involve anything too difficult or strenuous, there are a few tools that will make the job easier and safer including: ^ A flashlight ^ Along pole or broom handle ^ Some kind of pry bar or lifting tool for pulling manhole and grate covers ^ Gloves A resource list is included in the next chapter. Here you will find the phone numbers of the agencies referred to in the tables, as well as the contractors and consultants who designed and constructed your facilities. SAFETY WARNING: In keeping with OSHA regulations, you should never stick your head or any part of your body into a manhole or other type of confined space. When looking into a manhole or catch basin, stand above it and use the flashlight to help you see. Use a long pole or broom handle to check sediment depths in confined spaces. NO PART OF YOUR BODY SHOULD BREAK THE PLANE OF THE OPEN HOLE. OUR REDEEMER FAITH LUTHERAN CHURCH 11.22.Q5 PAGE 24 Infiltration Trench INSPECTION ::.AREA FREQUENCY LOOK FOR ACTION Storage Area Annually Sediment buildup in Remove sediment and/or clean facility system so that infiltration system works accordin to desi n. Storage Area Annually Slow draining (more than Enlarge the system or replace gravel 48 hours) or overflowing with large diameter perforated pipe. Aerate soil to improve drainage. Contact design engineer or City for more information. C7UR RECIEEMER FAITH LUTHERAN CHURCH 11.22.05 PAGE 25 Catch Basins, Manholes, and Inlets These structures are typically located in the streets and public rights-of-way. Local jurisdictions are responsible for routine maintenance of the pipes and catch basins in rights-of-way, while you are responsible for keeping the grates clear of debris in all areas as well as pipes and catch basins in private areas. INSPECTION FREQUENCY LOOK FOR ACTION .:AREA Catch basin During and after Accumulation of trash or debris in front of Remove blocking trash or debris with a opening major storms catch basin opening that prevents water from rake and clean off the grate. flowin in Catch basin Quarterly Sediment or debris in the basin. No more Remove debris from catch basin. than half the depth from the bottom of the pipe to the bottom of the basin should be allowed to accumulate. Use a long stick or broom handle to poke into sediment and determine de th. Inlet and outlet Quarterly Trash or debris in the pipes that has Remove trash or debris from inlet and pipes exceeded 1/5 of their height. Ensure there outlet pipes. are not tree roots or other vegetation rowin in the i es. Inlet and outlet Annually Cracks wider than''/2 inch and longer than Repair cracks or replace the joints. pipe joints 12-inches at the joint of any inlet or outlet pipe. Also check for evidence of sediment enterin the catch basin throw h cracks. Grate Quarterly Cracks longer than 2 inches or multiple Replace grate if necessary. cracks. Frame Quarterly Confirmation that the frame is sitting flush on Repair or replace the frame so it is flush top of the concrete structure (slab). A with the slab. separation of more than'/< inch between the frame and the slab should be corrected. Catch basin Annually Cracks wider than %2 inch and longer than 3 Replace or repair the basin. Contact a feet. Also check for any evidence of professional engineer for evaluation. sediment entering the catch basin through cracks. Determine whether or not the structure is sound. Catch basin Quarterly Chemicals such as natural gas, oil, and Clean out catch basin. Contact your gasoline have may have entered the catch local jurisdiction or Thurston County basin. Check for noxious odor or oily sludge. Environmental Health if you detect a color, odor, or oil slud e. Oil /water Quarterly Significant sludge, oil, grease, or scum layer Remove the catch basin lid and skim off separator covering all or most of the water surface. oil layer. Pour oil into a disposable (downturned container, seal container, wrap securely elbow or 'T" in in newspaper, and place in trash. Water catch basin surface should be clear of oil la er. Pipe elbow Quarterly Damage to top or bottom of pipe; determine If pipe is broken, replace pipe in whether pipe is plumb. accordance with approved plans on file with our local 'urisdiction. C)UR REDEEMER FAITH LUTHERAN CHURCH 11,22.05 PAGE 26 Fencing, Shrubbery Screens, and Gates Fences and shrubbery screens aren't typically required for stormwater ponds. If the slopes of the sides are too steep, usually some kind of barricade is constructed. INSPECTION ' FREQUENCY :LOOK FOR ACTION AREA Fence or Quarterly Inspect the fence or screen to ensure Mend the fence, repair shrubbery that it blocks easy entry to the facility. erosion, or replace the shrubs screen Make sure erosion hasn't created an to form a solid barrier. o enin under fence. Shrubbery Quarterly Confirm that shrubbery is not growing Trim and weed shrubbery to screen out-of-control or that it is not infested provide appealing aesthetics. with weeds. Do not use chemicals to control weeds. Wire Fences Annually Confirmation that fence is still in Straighten posts and rails if ali nment. necessar . Wire Fences Annually Missing or loose tension wire. Replace or repair tension wire so it holds fabric. Wire Fences Annually Missing, loose, or sagging barbed Replace or repair barbed wire wire. so that it doesn't sag between osts. Wire Fences Annually Rust or scaling Paint or coat rusting or scaling arts with a rotective coatin . Wire Fences Quarterly Confirm that there are no holes in the Repair holes so that there are fabric or fencing. no openings in the fabric or fencin . Gate Quarterly Confirm that the gate is not broken, Repair or replace the gate to jammed, or missing and that it opens allow entry of maintenance easily. people and equipment. If a lock is used, make sure you have a ke . GUR REUEEh.~ER FAITH LUTHERAN CHURCH 11.22.UJ PAGE 27 Conveyance Pipes, Ditches, and Swales YNSPECTION FREQUENCY LOOK FOR ACTION AREA Pipes Annually Confirmation that accumulated Clean pipes of all sediment sediment has not exceeded 20% of and debris. Remove all the diameter of the pipe and that vegetation so that water vegetation has not reduced free flows freely through pipes. movement of water through pipes. Repair or replace pipe as Ensure that the protective coating is necessary. not damaged and rusted. Dents should not significantly impede flow. Pipe should not have major cracks or tears allowin water to leak out. Open ditches Quarterly Yard waste or litter in the ditch. Remove trash and debris and dis ose of ro erl . Open ditches Annually Confirmation that accumulated Clean ditch of all sediment sediment has not exceeded 20% of and debris. the de th of the ditch. Open ditches Annually Vegetation (e.g., weedy shrubs or Clear blocking vegetation so &Swales saplings) that reduces the free that water flows freely movement of water through ditches or through ditches. Grassy swales. vegetation should be left alone. Open ditches Quarterly Signs of erosion. Inspect slopes for Eliminate causes of erosion. 8~ Swales signs of sloughing or settling. Action Stabilize slopes by using is needed where eroded damage is appropriate erosion control over 2 inches deep and where measures (e.g., reinforce potential for continued erosion exists. with rock, plant grass, com act soil. Open ditches Annually Adequate rock placement in splash Replace rocks to design & Swales pad, check dam or lining. Native soil standard. should not be visible. Swales Quarterly Adequate grass coverage. Take Aerate soils, reseed and action if coverage is sparse and mulch bare areas. Keep weedy, or areas are overgrown with grass less than 8 inches woody vegetation. high. Remove woody growth, regrade, and reseed as necessar . Swales Quarterly Confirmation that swale has not been If possible, speak with filled in or blocked by structures, homeowner and request shrubbery, etc. that the swale area be restored. Swales Annually Standing water in swale or very slow A survey may be needed to flow velocity. Stagnation. verify grades. Grades should be between 1-5%. OUR RcL}EENtER PAETH LUTHERAN CHURCH 1 1.22.05 PAGE 28 Grounds and Landscaping .INSPECTION .AREA........ FREQUENCY LOOK FOR ACTION Landscaped Quarterly Uncontrolled weed growth in If possible, pull weeds by hand Areas landscaped areas. to avoid using chemical weed controls. Landscaped Quarterly Presence of poison ivy or other Remove poisonous vegetation Areas oisonous ve etation or insect nests. or insect nests. Landscaped Quarterly Yard waste or litter Remove and dispose of Areas ro erl . Landscaped Quarterly Noticeably visible rills in landscaped Identify the causes of erosion Areas areas. and take steps to slow down or disperse the water. Fill in contour; seed area. Trees and Annually Split, broken or otherwise damaged Trim trees and shrubs to shrubs tree parts and shrubs restore shape. Replace severely damaged trees and shrubs. Trees and Annually Blown down or knocked over trees or Replant trees or shrubs, shrubs shrubs inspecting for injury to stem or roots. Replace if severely dama ed. Trees and Annually Exposed roots, inadequate support, Place stakes and rubber- Shrubs severe leaning coated ties around young trees/shrubs for su port. OUR REDEEMER FAWN LUTHERAN CHURCH 11.22.05 PAGE 29 Treatment Vault This facility is for pretreatment of stormwater prior to entering the infiltration pond. .:INSPECTION FREQUENCY LOOK FOR ACTION AREA Entire Treatment Quarterly Sediment or debris First, attempt to locate the source of the pollution; Vault then call the Moderate Risk Waste program at Thurston County Environmental Health to report the hazard; then call maintenance contractor. Inlet/Outlet Quarterly Sediment or debris. Call maintenance contractor. Treatment Vault Entire Treatment Annually Check maintenance Call maintenance contractor. Vault schedule. OUR REDEEMER FAITH LUTHERAN CHURCH 11.22.05 PAGE 30 Drywells, French Drains, or Downspouts .INSPECTION AREA FREQUENCY LOOK"FOR ACTION Downspout Annually Water overflowing from the First clean the gutters and downspout over the ground. downspouts. If this doesn't solve the problem, a larger dr ell ma be re uired. Roof Annually Moss and algae taking over the Disconnect flexible part of the shadier parts of the shingles. downspout leading to the drywell. Remove moss. Pressure washing or use of fatty acid solutions instead of highly toxic pesticides or chlorine bleach is preferred. Install a zinc stri as a reventative. OUR REDEEMER FAITH LUTHERAN CHURCH 11.22.Q5 PAGE 31 RESOURCE LISTING If you suspect a problem exists, please contact your local jurisdiction at one of the numbers below and ask for Technical Assistance. Contact Numbers: Yelm Public Works WSU Cooperative Extension (360)458-3244 (360)786-5445 Developer Information: Trans Northwest Construction 8625 Bedington Drive SE Olympia, WA 98513 (360) 413-0195 Engineer's Information: HATTON GODAT PANTIER 1840 Barnes Blvd SW Tumwater, WA 98512 (360) 943-1599 C7UR REDEEi49ER FAITH LUTHERAN CHURCH 11.22.05 PAGE 32 LOG SHEET Use log sheets to track maintenance checks and what items, if any, are repaired or altered. The completed sheets will serve as a record of maintenance activity and will provide valuable information about how your facilities are operating. Log sheets should be kept in a dry, readily accessible place. INSPECTION DATE: PERFORMED BY: PHONE NUMBER: ADDRESS: POSITION ON HOA: CITY, ST, ZIP: • ~: • ~• ~ ~ ~ ~ • ~ OUR REDEEMER FAITH LUTHERAN GHURGN 1122.Q5 PAGE 33 III. POLLUTION SOURCE CONTROL PROGRAM What Are Pollution Source Controls And Why Are They Needed? Pollution source controls are actions taken by a person or business to reduce the amount of pollution reaching surface and ground waters. Controls, also called "best management practices" (BMPs) include: ^ Altering the activity (e.g., substitute non-toxic products, recycle used oil, route floor drains to sanitary sewer rather than storm sewer) ^ Enclosing or covering the activity (e.g., building a roof) ^ Segregating the activity (e.g., diverting runoff away from an area that is contaminated) ^ Routing runoff from the activity to a treatment alternative (e.g., a wastewater treatment facility, sanitary sewer, or stormwater treatment area) Pollution source controls are needed because of the contamination found in runoff from commercial areas and the effect of this contamination on aquatic life and human health. Research on urban runoff in the Puget Sound area and elsewhere has found oil and grease, nutrients, organic substances, toxic metals, bacteria, viruses, and sediments at unacceptable levels. Effects of contaminated runoff include closure of shellfish harvesting areas and swimming areas, mortality of young fish and other aquatic organisms, tumors on fish, and impairment offish reproduction. Materials Used And Wastes Generated Of particular concern are drives and parking areas. Because of heavy vehicle usage, the concentration of oil and grease in stormwater may exceed the Ecology guidelines of 10 mg/1. Although there are no local data to confirm this view, limited research in the San Francisco Bay area found the mean concentration of oil and grease in stormwater to exceed 10 mg/1. Required Actions The following actions shall be taken to ensure that pollution generated on site shall be minimized: Warning signs (e.g., "Dump No Waste -Drains to Stream") shall be painted or embossed on or adjacent to all storm drain inlets. They shall be repainted as needed. Materials needed to undertake this task can be purchased or may be available from the Public Involvement Coordinator for the Department of Public Works. 2. Sediment removed from basins, ponds, and swales shall be disposed of in a proper manner. Contact the local governing jurisdiction for inspection prior to completing this task. 3. No activities shall be conducted on site that are likely to result in short-term, highly concentrated discharge of pollution to the stormwater system. Such activities may include, but are not limited to, heavy vehicle maintenance, and cleaning of equipment used in the periodic maintenance of buildings and paved surfaces. 4. Use of pesticides and fertilizers shall be minimized. 5. Do not dump paint, solvents, oils, or other such substances, including landscape waste, into storm drains or ponds. OUR RECEEMER FAITH LUTHERAN CHURCH 19.22.()5 PAGE 34 APPENDIX A -Soils Report ~~ t ;,y. ~, .~:: y : ~ ;~i i' ~~` - lye ~;.~. r DAMEL UFNAR 1220 Fouirrt-1 AvEivuE EnsT b ~ ~ ~y - Or..YN[r[n, WA, 98506 ~~., ~~; - VOICE: (360)-236-1899 FAx: (360)-236-7813 Trans Northwest Construction Mike Opitz 8625 Bedington Drive SE Olympia, WA 98503 August 24, 2005 Report File Number: SOS-0066 Report Subject: Soils investigation for stormwater facility design Location: The study site is located at 805 Yelm Avenue East, about 360 feet from Vancil Road SE, in Yelm, Washington. It is in the NE 1/4 of Section 30, Township 17N, Range 2E (Tax Parcel Number: 22730121100). INTRODUCTION An onsite soils investigation was performed on August 23, 2005, by Daniel Ufnar (soil scientist). The intent of the work was to identify and characterize onsite soil conditions and how they would affect stormwater facility design. The purpose of this document is to report the results of those investigations. Please note that the report below is based on the current requirements for site assessment and design. Anew stormwater design protocol is expected to be adopted over the next month to six months which may require additional field work to be carried out or data to be collected METHODS AND MATERIALS Office Research The Thurston County Soil Survey was consulted to determine how local soils are mapped and to determine if some areas might be better suited than others for onsite stormwater infiltration. Field Research On August 23rd , 4 soil pits were excavated with an excavator to a maxunum depth of 14 feet onsite (See site map, Appendix IV). All pits were located in the vicinity of the proposed stormwater management facilities. Soil profiles were described in each pit with special emphasis on soil texture and structure in each horizon. Soil pits were also evaluated for any sign of a long-term or seasonal water table. Information obtained from the soil profile description was also used to estimate potential soil page 1 D^-~>~~~ percolation or infiltration rates. RESULTS AND DISCUSSION Site Description The study site consists of the two northern proposed lots (a combined 1.71 acres) of the property located at 805 Yelm Avenue East, about 360 feet from Vancil Road SE, in Yelm, Washington (vicinity map, Appendix IV). The site is currently owned by Our Redeemer Lutheran Church of Yelm, WA, which operates an existing church on the property (Lot 4 on the preliminary site plan-Appendix ]V). There is also an abandoned home in the northeastern portion of the property with two associated out-buildings. There are a number of large black locusts, Douglas-firs and a few western red cedars surrounding the house, along with a mixture of ornamentals and big-leaf maples in the front of the house. The remainder of the property is dominated by mowed fields. It is proposed to knock down the existing home and convert the northeastern lot into a carwash. The lot adjacent to the west will be potentially converted for commercial use in the future. The preliminary site layout map provided by the client indicates an area to the north and east of the existing home as well as an area to the north of the church as potential locations for stormwater facilities. According to the topography data obtained from the Thurston County GeoData (TCGD) system (Appendix IV), overall site relief is about 6 feet. Onsite elevation ranges from a low of 344 feet along the southern border of the property (south of the church) to a high of 350 feet along the northern properly boundary along Yelm Avenue. The site topography gently slopes to the south at less than 3% grade. The nearest body of water, according to the TCGD is Yelm Ditch, located about 470 feet south of the site with a surface elevation of about 356 feet. Yelm Creek is located about t/Z of a mile to the northeast at a surface elevation of 338 feet. Both systems are known to have areas where water flows over a restrictive layer that perches the water table. So while those systems may periodically overflow and affect groundwater in the immediate vicinity of the creeks, they are not expected to have a significant impact on study site groundwater hydrology. However, there are areas of Yelm that have a groundwater table within 10-20 feet of the soil surface. But no indicators of that were observed at this site. The site is not mapped as a flood or high groundwater hazard area. Mapped Soils Description According to the Thurston County Soil Survey, the following soil series are mapped on the site: 1) Nisqually loamy fine sand, (classified a sandy, isotic, mesic Vitrandic Dystroxerept'). The ' Sandy, isotic, mesic Vitrandic Dystroxerepts, generally meaning the soil has minimal horizon development (ept), has developed under conditions of winter precipitation and summer drought (xer), has a low sub-surface base saturation, generally indicative of poor nutrient status (Dystro), and has been influenced by coarse textured or young volcanic materials (Vitrandic), has developed under conditions of a mesic climate (mean annual temperature ranges from 8° to 15° C (47° - 59° F), has a high water retention to clay content ratio and has derivatives from the page 2 Nisqually loamy fine sands aze very deep, somewhat excessively-drained soils formed on ancient terraces and floodplains in sandy glacial outwash. These soils aze mapped in the extreme southern portion of the property. 2) Spanaway gravelly sandy loam, (classified as asandy-skeletal, mixed, mesic Typic Melanoxerandsz). The Spanaway gravelly sandy loamy are very deep, somewhat excessively drained soils on terraces formed in glacial outwash and volcanic ash. The Spanaway series is mapped across the majority of the property and is the only series mapped in the vicinity of the areas investigated. For your information, standard chazacteristics of the mapped soil series are described in Appendix II. Please note that the NRCS (formerly the SCS) soil series maps and descriptions represent expected characteristics in only the ton 60 inches of soil. Furthermore, the map units can have extensive inclusions of other soil types, and in some rare cases, can be entirely in error. Taxonomic descriptions listed reflect the most recent changes to Soil Taxonomy and represent the current accepted understanding of soil forming processes. These soil taxonomic names do not necessarily correspond to those listed in the Soil Survey of Thurston County, Washington since it was published under an earlier version of Soil Taxonomy. Please refer to the individual pit descriptions in Appendix I and to the discussion in the text below for specifics on observed site soil conditions. Onsite Soil Descriptions Four soil pits were excavated and described onsite for stormwater facility design purposes. Pits 1 and 2 were located in the northeast lot. Pit 1 was excavated to the northwest of the abandoned house mentioned above and to the west of a lazge big-leaf maple shrub. Pit 2 was located northwest of Pit 1 and about 50 feet west of a western redcedaz along Yelm Avenue. Pits 3 and 4 were located on the adjacent lot and north of the gravel parking circle in front of the church. Pits 3 and 4 were approximately 50 feet apart. All four pits had a surface elevation (as determined from TCGD derived data) of approximately 348 feet. Please see the site map located in Appendix IV for approximate pit locations. The soils in all four pits were typical of the Spanaway soil series, and soil characteristics were fairly uniform among the four pits examined. They all had about 2 feet of dazk-colored, gravelly (coazse fragment content averaged about 20 percent) loam at the surface. It should be noted that high volcanic ash and organic matter content (i.e., high sealing potential) is typical of these dark surface layers. Transitional AB or BA horizons were noted between surface and subsurface break down of noncrystalline minerals (isotic), and has less than 35% coarse fragment content and is either sandy or loamy sand with less than 50%very fine sand content (sandy). 2 Sandy-skeletal, mixed, mesic Typic Melanoxerands, generally meaning the soil is of volcanic origin (ands), has developed under conditions of winter precipitation and summer drought (xer), has adark-colored, organically rich, volcanically influenced surface horiwn (Melano), and has otherwise average characteristics for these soil types (Typic), has a mesic temperature regime (mean annual temperature ranges from 8° to 15° C (47° - 59° F), has no specific mineralogic source (mixed), has 15-50% sand by weight and greater than 35% coarse fragments by volume (sandy-skeletal). page 3 layers; they were generally higher in organic content and darker in color than the subsoils described. Textures were very gravelly (40 to 50% gravel content) sandy loam and colors were typically very dazk grayish brown. These layers extended to a depth of about 2.5 to 3 feet and aze considered to be part of the soil surface horizons for this discussion. A weakly developed brown subsurface B horizon (averaging between 8 and 10 inches in thickness) was noted in all four pits. Textures were very gravelly to extremely gravelly loamy medium sands (although textures in Pit 2 within this layer were finer) with coazse fragment contents exceeding 50 percent. There were no signs of mottling or other indications of a seasonal or long-term groundwater table within these layers. Please note that detailed pit descriptions aze located in Appendix I. Below about 3.5-4 feet in all the pits, the soils became dominantly (exceeding 70%) glacial outwash gravels and cobbles; the remaining 25-30% were olive brown medium sands. This material is expected to infiltrate water at rates exceeding 20 inches per hour, and should be targeted for stormwater facility design. While black Manganese (Mn) stains on the undersides of cobbles were common in all of the pits examined, this type of Mn staining is not typically a sign of long duration saturation, but rather is a result of Mn laden groundwater condensing and then evaporating on rock bottoms. There was no evidence (mottling, seeping water, etc.) for a current long-duration or seasonal high groundwater table in the surface 14 feet of soil examined (which translates to an elevation of 334 feet if the base of the test pits are converted to an elevation). The surface elevations of Yehn~Ditch and Yehn Creek (listed above) are both higher in elevation than the base of our test pits, which indicates these systems are perched and do not represent the true regional groundwater table. No evidence of a seasonal groundwater table was found in any of the pits examined. Recommendations We recommend that the base of the infiltration facilities be sited 4 feet below the existing surface to ensure the infiltration surface is installed in the highly permeable C horizons. As was stated, the very gravelly to cobbly loamy medium sands aze expected. to infiltrate at rates of greater than 20 inches per hour in an undisturbed native condition. When we have tested similaz soils, rates of between 50 and 100 inches per hour were common. For those reasons, we recommend designing at the maximum allowed infiltration rate of 20 inches per hour. In order to maintain this rate over time, the base of the facility should be left open -- meaning it should not be vegetated (assuming an open pond design is used) -leaving the gravels and cobbles exposed and un-graded. If a trench design is used, a long and narrow design shape (trench rather than box) is recommended to minimize any incidental groundwater mounding effects (not expected to be significant) and to take advantage of as much side wall area as possible. Special care will also be needed to ensure that the black loam surface material is removed and is not allowed to wash back into the base of the infiltration facility. This will act to minimize sealing potential, which is high in this particular soil. Building in the summer months as well as seeding or landscaping the upper pond sidewalls (if an open pond design is used) will also help to minimize potential erosion hazazds. Grass seeding and page 4 establishment will be difficult due to the subsoil's excessive drainage and low nutrient status. Sprinklers or some other source of watering will be required to ensure vegetative establishment and long-term survival. The main limitation for facility design in these types of soils is the gravelly subsoil's poor filtering capacity - a result of rapid percolation rates and relatively low silt and clay content. Grass-lined swales and other filtration conveniences or filtering systems are encouraged for pretreatment of stormwater prior to infiltration. Considering the high infiltration capacity of soils across the entire site, we recommend installing drywells for all structures to infiltrate roof runoff from the proposed buildings. Again, the C horizons below 4 feet should be targeted for infiltration and the black loam surface material should be completely removed and kept from eroding back into the drywell base to maximize infiltration potential. Long-narrow trenches built parallel with the slope work best. I hope this report provides enough information to proceed with project planning. Please call if you have any questions or require additional detail or clarification on any of these issues. Th You, Pacific Rim Soil & W er, c. Daniel Ufiiar SSSA APSC soil classifier #32300 Lisa Palazzi ARCPACS certified soil scientist Certification #3313 page 5 APPENDIX I SOIL PROFILE DESCRIPTIONS APPENDIX I Pit 1 Horiz D,~ Col CF Txt Struc Perc Mott Roots OM %C A 0-22 10YR2/1 20 GRL WMGR 0.2-0.6 - MF,CM,CC 8 12 AB 22-34 10YR3/2 40 VGRSL SG 0.6-2 - MF,CM 4 10 Bw 34-42 10YR5/4 70 XGRLMS SG 20+ - FF <3 <10 2C 42-168 2.SY4/3 75 XGRMS SG 20+ - - <3 <5 Typical Spanaway soil series. Very dark loamy surface underlain by very gravelly trending to extremely gravelly and cobbly medium sands with depth. Manganese (Mn) staining on the undersides of cobbles was common. Soil was dry and no sign of seasonal high water table within surface 14 feet. Infiltration rates will exceed 20 inches per hour in the C horizons under natural conditions, and should be targeted for. onsite infiltration. Pit 2 Horiz Dnth Col CF Txt Struc Perc Mott Roots OM %C A 0-26 10YR2/1 20 GRL WMGR 0.2-0.6 - MF 8 12 BA 26-32 10YR3/2 50 VGRSL SG 0.6-2 - MF 3 10 Bw 32-41 2.SY4/3 55 VGRSL SG 6-2018 - CF <3 10 2C 41-160 2.SY4/3 75 XGRMS SG 20+ - - <3 <5 Refer to Pit 1 description. Pit 3 Horiz D~ Col A 0-22 10YR2/1 AB 22-31 10YR3/2 Bw 31-41 10YR4/3 CF Txt Struc 20 GRL WMGR 40 VGRSL SG 50 VGRLMS SG 70 XGRMS SG Perc Mott Roots OM %C 0.2-0.6 - MF 8 12 0.6-2 - MF 5 10 20+ - CF 3 8 20+ - - <3 <5 2C 41-162 2.SY4/3 Refer to Pit 1 description. Pit 4 Horiz Dnth Col A 0-22 10YR2/1 AB 22-36 10YR3/2 Bw 36-40 10YR5/4 CF Txt Struc 20 GRL WMGR 40 VGRSL SG 55 VGRLMS SG 75 XGRMS SG Perc Mott Roots OM %C 0.2-0.6 - MF,CM,CC 8 12 0.6-2 - MF,CM 4 10 20+ - FF <3 <10 20+ - - <3 <5 2C 40-144 2.SY4/3 Refer to Pit 1 description. page 6 APPENDIX II SOIL SERIES DESCRIPTIONS APPENDIX II NISQUALLY SERIES The Nisqually loamy fine sands are very deep, somewhat excessively-drained soils formed on ancient terraces and floodplains in sandy glacial outwash. Generally, the upper 26 inches are very dark-colored, highly organic, loamy fine sands; the underlying horizons are lighter colored with an abrupt drop in organic content, and slightly coarser in texture, grading to loamy sands. Average soil permeability near the surface is moderately rapid (2-6 inches per hour) grading to very rapid (>20 inches per hour) in the subsoils. The Nisqually soils are generally suitable for hayland, pasture, woodland and homesites with few limitations. Easy tilth and good drainage properties also make them excellent irrigated cropland soils. (They have only moderate water holding capacities and require regular irrigation during summer months.) Due to rapid percolation rates in subsoils, however, water applications of any sort (e.g. stormwater or septic effluent) should be closely monitored and controlled to minimize leaching of solubilized nutrients and other pollutants into underlying susceptible groundwater aquifers. SPANAWAY SERIES The Spanaway gravelly sandy loamy are very deep, somewhat excessively drained soil on terraces formed in glacial outwash and volcanic ash. The top 20 inches are expected to be very dark- colored gravelly to very gravelly loamy and sandy loamy. Subsoils are expected to be extremely gravelly sands. In some areas, these soils can also be very stony (rocks larger than 10 inches in diameter). Soil percolation rates are expected to be moderately rapid (2-6 inches per hour) near the surface and very rapid (greater than 20 inches per hour) in the extremely gravelly sand substratum. These soils are used mainly as hayland, pasture, or cropland, as homesites, or as a gravel source. The primary limitation for any vegetation-related use is the very low water holding capacity in the subsoils. The volcanic ash influence in these soils may be evidenced by fine-textured soils in interstices between coarse fragments. Furthermore, these soils may show an increased tendency to cement or compact firmly in surface horizons when disturbed. The volcanic ash particles tend to break down into amorphous clays -- a silica gel. The main limitation for septic system (or stormwater pond) design is the gravelly subsoil's poor filtering capacity -- a result of rapid percolation rates and relatively low silt and clay content. Community sewer systems or alternative septic systems (usually sand filter and/or pressure distribution) are encouraged to avoid contamination of groundwater or nearby wells. Grass-lined swales or sand lined ponds may be encouraged for pretreatment of stormwater prior to infiltration. page 7 APPENDIX III DEFINITIONS APPENDIX III DEFINITIONS Soil Profile Description Column Headings: Horiz =horizon: This word refers to the horizontal bands of soil parallel to the surface that form at various depths from the surface as a result of the leaching and accumulation of organic matter, clays, metal oxides and other salts via the weatherin action of water. A list of common master horizons and their criteria follows. Table 1: Master Horizon descri tions Horizon Criteria O Predominantly organic matter (leaf litter and humus) A Mineral horizon with an accumulation of organic materials and the loss of Iron, Aluminum, and clay B A subsurface horizon showing signs of an accumulation of clays, Iron, Aluminum, Silica, Humus (organic matter), carbonates, sulfates, other salts or a mixture of several of the above via illuvial (additions from above layers) or insitu processes. C Shows little sign of pedogenic alteration (i.e. accumulation or loss of clay, organic matter, Iron, Aluminum, etc.) from original parent materials. Often made up of unconsolidated earthy material and/or soft bedrock. R Hard continuous bedrock. Master horizons can be used in combination with each other to indicate a transitional or varied horizon. These combinations can take two separate forms; l) a horizon could be dominated by properties of one master horizon but have subordinate properties of another (an example would be an AB horizon, which has characteristics of both an overlying A horizon and an underlying B horizon, but it is more like an A horizon than a B horizon). These horizons tend to represent a transitional layer; or 2) a horizon may have two distinct parts that have recognizable properties of the two kinds of master horizons, in which case the combination of horizons are separated by a virgule (n. Examples include AB, or B/C horizons. These horizons typically represent layers that have individual parts of one horizon component surrounded by the other. A small letter, a horizon suffix, following the capital letter provides additional information and further describes Master Horizons A list ofhorizon suffixes and their criteria alon with the Master Horizons associated with each suffix follows. Table 2. Master Horizon Suffix descri tions Horizon Criteria Example shown with Suffix appropriate Master Horizons a Highly decomposed organic matter. Oa b Buried genetic (native) horizon. Ab, Bb d Densic layer (physically root restrictive); caused by a mechanical or Cd physical rather than chemical process; an example would be basal till (formed by compaction from the weight of an overlying glacier). e Moderately decomposed organic matter. Oe g Strong gley (low chroma) colors; caused by long duration saturation Bg, Cg causing the chemical reduction and subsequent translocation of Iron . -1- h Illuvial (an addition from layers above) organic matter accumulation. Bh i Slightly decomposed organic matter. Oi m Strong cementation caused by pedogenic (natural ongoing chemical, Bm physical alterations) processes-soil is massive in its lack of structure. (Example: an iron pan-Bsm (sesquioxides) or Bvm (Ironstone).) p Plow layer or other artificial disturbance-typically to surface layers. Ap r Weathered or soft bedrock; also an indicator of moderate to slight Cr cementation and is often used when describing cemented till. s The illuvial (addition from above layers) accumulation of sesquioxides Bs (a mixture of Iron and Aluminum oxides along with organic matter). Is atypical cementing agent and can be used in combination with horizon suffix `m'. t The illuvial (addition from above layers) accumulation of clays. Bt v Presence of plinthite-an Iron rich, humus poor, hard reddish material Bv, Cv often forming from prolonged wet and dry cycles. Often referred to as Ironstone-this material often forms a platy, polygonal, or reticulate pattern. Typically found in old, highly weathered soils and could be considered an Iron pan if horizontally continuous (in which case it would be used in combination with the horizon suffix m-"Bvm"). w Weak color or structure-indicating only slight alterations to original Bw parent material. x Fragipan (a firm yet brittle pedogenic layer high in bulk density that Bx can perch water and is somewhat root restrictive) characteristics. Formation is poorly understood, and differs from other hard pans in that these layers are not cemented with a specific cementing agent (such as Iron) but are instead hi in bulk densi and often massive. A `2' in front of a B or C horizon (Example: " 2B" or " 2C") indicates that the subsoils have a different parent material than the overlying soils. A `2' after a horizon (Example: "Bt2" or "Cg2") indicates a subdivision of that type of horizon based on a morphological change (color, texture, etc.) with depth. Dpth =depth: gives the distance in inches (unless otherwise noted) from the ground surface for the top and bottom of each horizon. Col =color: gives a Munsell Book color chip code. The Munsell color codes give information on the hue (the dominant spectral color -red, blue, etc.), value (the relative lightness or darkness of a color -the higher the value the lighter the color), and chroma (the purity or richness of a color -the higher the chroma the more brilliant or less gray the color) of the soil. In the example lOYR 2/2, the hue is l OYR, the value is 2, and the chroma is 2. Soil color can be used to infer parent material, percent organic content, or soil drainage characteristics. For example, soils with both low chroma and value (example: lOYR 2/2) are very dark-colored and tend to have high organic matter contents; soils with a Munsell chroma code of 2 or less (example: l OYR 7/2) may be poorly drained. Table 4 shows the value/chrome color codes that correspond to soil color names for the two most commonly used HUE pages lOYR and 2.SY. Txt =texture: describes the relative dominance in size of soil particles smaller than 2 mm diameter. Sand, silt, and clay are the three size classes with sand being largest and clay being smallest. The textural names are applied based on the weight percentage of sand (S), silt (Si), and clay (C). The textural name is derived from the field estimate of -ii- percent sand, silt and clay. Table 3 provides additional information on these abbreviations. CF =percent coarse fragments. Coarse fragments are defined as any mineral fragment in the soil greater than 2mm diameter. If needed, coarse fragments are also described in terms of various size classes -- gravel, cobble, stone. Abbreviations associated with CF percentages will be: GR=gravelly (between 2 and 76 mm (<3 ") diameter); CB = cobbly (coarse fragments between 3-10" diameter); ST=stoney (between 10-25" diameter). If no abbreviation is included, assume that the percent CF is describing gravels (coarse fragments >2 mm and <3" in diameter). If coarse fragment content is expressed as 15-35 percent, the fine fraction (soil particles less than 2 mm diameter) textural designation is modified and defined as gravelly (i.e. gravelly loam or gravelly silty clay); 35-65 percent is very gravelly; greater than 65 percent is defined as extremely gravelly. Struc =structure: describes the shape and size of the natural soil aggregates. Soil with strong structure is generally considered to be stable and well developed. Soils that are periodically disturbed generally have poor structure or are structureless. Fine textured soils with weak structure often have poor percolation capabilities. Parent materials that are unaltered are often structureless (either single grained or massive). These parent materials can be highly permeable material if the textures are coarse (such as sands and gravels, which are single grained), or they can be effectively impermeable if the textures are fine silts and clays (which are massive). Structural type, grade, and size are recorded. Table 3 provides additional information on these abbreviations. OM =percent organic matter. In mineral soils, organic matter decreases with distance from the soil surface. Low percentages (3% or less) at the surface can indicate erosion problems. Increased percentages below the surface can indicate a buried surface (fill on the surface). Organic matter improves structure and fertility. Surface OM% in mineral soils ranges from 4 to 20%. When OM% is greater than 20%, the soil maybe classified as an organic rather than mineral soil. This is generally indicative of saturated and/or cold conditions in the soil. Root =root presence. The rooting depth can be used to locate layers in the soil that may restrict growth or water movement. Root prominence and size (diameter) are measured Table 3 provides additional information on these abbreviations. Mott =mottles. Mottles are an indication that the soil goes through alternating periods of extended saturation and drying. Mottle prominence, size, and contrast are measured. Table 3 provides additional information on these abbreviations. Perc =percolation rate. The percolation rate is an estimate of inches per hour water percolation through the soil. The range in percolation rates as devised by the NRCS (formerly the SCS) are as follows: Class Estimated inches/hour Very slow less than 0.06 Slow 0.06-0.2 Moderately slow 0.2-0.6 Moderate 0.6-2.0 Moderately rapid 2.0-6.0 Rapid 6.0-20 Very rapid more than 20 The field estimate is made based on soil texture, percent coarse fragments, and other soil features, such as indication of cementing and the presence of mottles. Type =soil type: as defined in Article IV, Rules and Regulations of the Thurston County Board of Health Governing Disposal of Sewage (same as State definition). These groupings have been recently reviewed and revised at the State level, but in general indicate soil texture and relative percent of coarse fragments with the Type 1 soils being the most coarse-textured with the highest coarse fragment percentage and the Type 6 soils being the finest textured. Similar to soil percolation rate estimates, the field typing estimate is based on interpretation of effects of soil texture, percent coarse fragments, and other soil features, such as indication of cementing and the presence of mottles. In -iii- general, soil type 1 is too coarse textured to allow for a standard design. Some pre-treatment design is used, then the native soils are used for disposal of the treated effluent. Soil types 3 and 4 are generally preferred, although some type 4's may be limited to some degree by slow percolation; type 5 soils percolate very slowly and are generally less desirable due to how easily they are hydraulically overloaded, but mound or pressure distribution systems can be used in some cases to compensate for these limitations; type 6 soils are unsuited due to minimal percolation. %C =Percent clay content as estimated using hand-texture techniques in the field. Table 3: Field Data Abbreviations C = Clay(ey)* L = Loam(ey) S =Sand(y) Si =Silt(y) Modi iers CO =Coarse CB = Cobbly F =Fine GR =Gravelly ST =Stoney V=Very X =Extremely uanti (15` character) F =Few C =Common M =Many Size (2"d character) F =Fine (< 2 mm) M =Medium (2-5 mm) C =Coarse (> Smm) uanti (15S character) F =Few C =Common M =Many Size (2"d character) F =Fine (< 2 mm) M =Medium (2-5 mm) C =Coarse (> Smm) Contrast (3`d character) F =Faint D =Distinct P =Prominent Grade (1 ~` character) W =Weak M =Moderate S =Strong Size (2"d character) F =Fine M =Medium CO =Coarse Type (3'~ character) GR =Granular ABK =Angular Blocky SBK = Subangular Blocky PL =Platy Structureless SG =Single Grained MA =Massive -iv- Table 4: Mansell Color Codes translation to descri tive color names. lOYR HUE 2.5Y HUE COLOR NAME COLOR NAME VALUE/CHROMA VALUE/CHROMA white 8/1 white 8/1 light gray 7/1, 7/2 light gray 7/1, 7/2 gray 6/1, 5/1 gray 6/1, 6/2 dark gray 4/1 dark gray 4/1 very dark gray 3/1 very dark gray 3/1 black 2/1 black 2.5/1 very pale brown 8/2, 8/3, 8/4, 7/3, 7/4 pale yellow 8/2, 8/3, 8/4, 7/3, 7/4 light brownish gray 6/2 light brownish gray 6/2 grayish brown 5/2 grayish brown 5/2 dark grayish brown 4/2 dark grayish brown 4/2 very dark grayish brown 3/2 very dark grayish brown 3/2 very dark brown 2/2 yellow 8/6, 8/8, 7/6, 7/8 yellow 8/6, 8/8, 7/6, 7/8 light yellowish brown 6/3, 6/4 pale brown 6/3 light olive brown 5/3, 5/4, 5/6 brown 5/3, 4/3 olive brown 4/3, 4/4 dark brown 3/3 dark olive brown 3/3 light yellowish brown 6/4 olive yellow 6/6, 6/8 brownish yellow 6/6, 6/8 yellowish brown 5/4, 5/6, 5/8 dark yellowish brown 4/4, 4/6, 3/4, 3/6 -v- APPENDIX IV PROJECT MAPS s~ ~_ ~~ ~~ ~° ~~ =o ~~ ~Z n~ g' o a$ ~g o- ~< a$ ~~ V ~ ~ G f ~ ~~ m © ~ r ~ ~ .g o~ V U Soil Map - Yelm Carwash Site ti./ - 1 1 U 1 1 1 Y'~1m . ~ 114 llo `i4 112 t X12 6\ ,l 1 l 110 ~~~ A'9~. 11.:2 r ~ -, 'pi~c. 74 113 1 P('DJ Ct ItPY10 d~ 0 110 65 r 11.3 74 110 33 ~ 114 127 30 10 114 112 111 11..0 ~ 110 65 111 '. 111 3 \~ 33 _ J \ I Thurston County Soil Survey Map Unit Soil Tvne 74 Nisqually loamy fine sand, 3-15% slopes 110 Spanaway gravelly sandy loam, 0-3% slopes File Reference Number: SOS-0066 HUG-IU-ZUUb W@U UI~L( rrl HHIIUK 4UUH1 YHIVIICK um~xgwduWle4 ,;•. ~~ -001=.1 ~''~ 66ZB'LSC'OVC 7(Y~ OBS1'kY8'Oif T~1 ~ Z/S6BVM7131VMWnt ^. M3OWiH1n06 S>3NtlYy 01YL ~'pS-7CB'FDOl9B0 StlOA3Atln5 OHtl Sil33NI~JN3 ~~~ a311Ndd 1~+00J NOlltlH i~ .~ e.~ r~ :~ ~~i .~ .L. ~, i ~ ~'r 1Po-~-c,L T / /3 L S j c,~ryt u'i9 T 5ca ~ ~ P / -~'~ rHn nu. aou ail ocaa r. uc Nr"7d H11S .lLlb'N/W!?32/d 3 enuany w/a,~ gp@ T~ H91rM?f~ iM73.[ aTw Y ~~~~~ ~ g-"g w gg 8 ~ I ~~a~ ~ ~~ ~ ~ ~~~ ~ ~~ ~ ~~ ~ CL c ~ i; : ~ ? i i i t ~~.,, ~+ PAMTlw Q gooE3 ~ ~ ~ ~ ~~ ~~ _ . ~ ~ "Thurston County Map Uutput Yage rage i or 1 http://geomap l .geodata.org/servlet/com.esri.esrimap.Esrimap?ServiceName=cadastralov&... 8/23/2005 t~ ~; 5 lc.~ So I te.. ~ -~S APPENDIX B -Wet Vault Sizing Status of DEFAULTS at start of run. ( * May be reset by SET) "Command file -C:\HYDRA\CMII\II~-QT9.CMD Input units are read as ~JSA * Output sent to display Detailed * Output sent to printer Brief. * Output sent- to file Detailed Paper width in inches 8.000 String to reset printer 2751 36.18 String to set printer to compressed 17 15 String to set .printer to 8 lines/inch 8 27 51 27 Name of printer Epson,. FX series Print heading at top of page False Number of steps in hydrograph 9-6 Step length-in minutes :._15-- Significant -flow in hydragraph (1,.010 * Maxi-mum plot value ~elec-tech by HYP~RA Type of hydrographic plot Co€~pa~c-t, Sanitary flow by ~ Di~trga3 -Curve Delay to- start of_ actual -stQr~ 4 . f~fl Rational-Method computat3orr~ °Off 8CS computations- Sairta Barbara Continuous - simulation- ~omput-ati-orrs: Dff *- Maximum d"/D for pipe de-sign~anaiyss ~ ."9DD . * Ma~cl~ point position on pipe- rtT,~O or -lnyert * Numbe-r- of allowable dam drops- 9-9~ * Mimimum drop thru manhole 0.000 Routing technique ¢uick * Calculate sanitary flows True * Calculate infiltration fl-ows Txue * Calculate_ storm flows Txue * Calculate misc. flows 'true 1: JOB Yelm Car Wash 6-month 24 Hour 2: REM Size the wet vaults 3: 4 : TOT ~.. 3 3 5: 6: REM 6-month 1.33 in 7: REM 100-year 4.00 in 8: 9 : FIL doe. inc "'calls the doe_ unit_ hydrog~aph ------START OF SUB-FILE------ l: HYE 10 0.00 0.040 0.040 0.440- 0.04-0 0.040- 0.040 0.040 0.0-40 0.04.0 0.0 40+ 2 : 0 .050 0 .050 0 .050 O . Q5_Q 0 _O~Q 0 _0.~0 0 _0.8.0 0 .060 0.-0FiQ O ..0.6.0 0.060 0.060+ 3: 0.070 0.070 0.070 0.070 0.(170- 0.070 (1.082 0.082 0.082 0.082 0.082 0.082+ 4 : 0 .095 0 .095 0 .095 0...0.9.5. Q_035 0 ~Q35_ Q~13.4 0 .134. 0_._13.4. 0 .18_Q 0..180 0.340+ 5: 0.540 0.270 0.180- 0.134 0-.13.4 0.134 0.088 0.088 0.088 0.0-88 0,088 0.088+ 6: 0.088 0.088 0.088 O.D88 "0.088 D.~088 "0.072 0.072 0.072 0.072 0.072 0.072+ 7: 0.072 0.072 0.072 0.072 4.472 4.4-72 Q.-057 0.057 Q.057 0.05-7 0-,057 0.057+ 8: 0.057 Q.057 0.05-7 Q..Q57 Q__O57 Q-..05.7 0._050 Q_.Q5_Q 0..0.5.0.Q.Q5Q Q,. 050 0.050+ 9: 0.050 0.050 0.050 0.454 0.454 0-.45.4 0-.040 0-.040 0.0.44.0.040 0.040 0.040+ 10 : 0 .040 0 .040 0-._Q40 0._0.40. 0 _A40 Q _040. 0._:040 0.04_Q 0 ~Q.4Q Q ._Q4Q 0, 040 0.040+ 11: 0.040 0.040 0.044 4.044 0.044 4.044 4.440 0.040 4.-0.40 0.-444 4..040 0.040+ 12: 0.040 0.040 0.040 0_040 0_040 0_.040 0__Q4Q 0.0:40 0..:04.0.0...-0.40 0.040 0.040+ 13: 0.040 0.040 ----- END OF SUB-FILE ------ 10: 11: PDA 0.012 8 1 2 2. Q__QO5 "' sets` default pipe. vaJ-ues 12: NEW Car Wash pavemnet and landscaping 13: SCS 0.44 1.0098 80 2 "area percent. impervious, CN impervious,. Cn p ervious, TC 14: RES -1 0/0 999999999/0 NOTE: No flow to inlet. 15: 16: NEW Private-Road 17: SCS 0.51 1.00 98 80 2 18: RES -1 0/0 99999999999/0 NOTE: No flow to inlet. 19: 20: END ------ S U M M A R Y O F A-N A L Y S I S------ Run nu~ber on command file Number of links :- Number of hyclrographs Total sanitary papui.ation Total sanitary area Tat.a1. starni -a.rea Number of pumps Number of reseruQirs ": Number of diversion. structures Number a£ inlets Length of new pipe Length Qf existing pipe Length of c3~annel Length of gutter Length pf transport units I.~en_gth. of_ pressure pipe. 2 2 4~ 0 0.00 Acres Q_.-~.~ Acres 2 0 0 0.00 Feet 0_ _ Q.Q. ~'ee t 0.00 Feet Q_0O- Feet U.00 Feet 0 _ 0 0 Eee-t_ HGA, Consulting Engineers HYDRA Version 4.59 pl~mpiar WaGh~t.on. Page 1 C~\HYDRA~CMD~05-079.CMD ------ 13:iS 22--ATE-105 Yelm-Car Wash 6-month 24 Hour *** Car Wash ga_vemnat and__landeca~in_ RP~er~oir Invert -------------- Maximum Flow Values ------- ------ ---- 'Link LIp./ Dn Han_ T n f S_t.a_ Mis De.sign_ ~o s t 1 Unknown Discharge 0.00 D.~D ~.DD D.DO D.DO 0 Unknown Stored : 0 0 1774 0 1774 Incoming 0 .0D 0 . DD D .14 D ."OD 0 .-14 Lateral 3engt~i= ff I~pstream ierrg~~.= fl- *** Private Road Reservoir Lnvert -------------- Maximum.. Elc,w ya1uP~ ------- ------ ---- Link Up/Dn -San Inf 8to Mis Design Cosh 2. Unknawr~ Discharge _ ~ Q__QQ _ Q _ Q0. Q : O Q Q ~:0 0 0. ~ QQ 0 Unknown Stored 0 0 2056 0 2056 Incoming o __aa_ a ._a0___ a .~., a..-aa p .16 ---------------- Lateral Iength= --------- 6 ------------------- Upstream Iength= ------ -- 0 APPENDIX C -Infiltration Sizing Calculations On-site Infiltration 5' Volume Provided 563 CF Min elevatin void ratio = 0.3 1' min length 70 ft infiltration °' o rate= 20 in/hr ° 0 ° ° Qow 0.16 ft'/sec o 0 total volume 563 CF 5.~' Bedding 2.00 Cover 2.0 0 0 " Diameter 1.0 12 "pipe ° o Radius 0'.5 ° o ~ width 5.0 ° Dist. from bottom of n~/n B Unit Volume UnilTrench Total Unit Total volume trench 1 of Pipe Volume Volume of trench 0,00 0 0.0000 0.000 0.000 0.000 0 0.10 0 0.0000 0.000 0.150 0.150 11 0.50 0 0.0000 0.000 0.750 0.750 53 1.00 0 0.0000 0.000 1.500 1.500 105 1.50 0 0.0000 0.000 2.250 2.250 158 2.00 0 0.0000 0.000 3.000 3.000 210 2.50 0.5 3.1416 0.393 3.632 4.025 282 3.00 1 6.2832 0.785 4.264 5.050 353 3.21 1.21 6.2832 0.785 4.579 5.365 376 3.35 1.35 6.2832 0.785 4.789 5.575 390 3.50 1.5 6.2832 0.785 5.014 5.800 406 4.00 2 6.2832 0.785 5.764 6.550 458 4.50 2.5 6.2832 0.785 6.514 7.300 511 > than the 100yr event, 487 CF 5.00 3 6.2832 0.785 7.264 8.050 563 Page 1 Access Road • -• 5' Volume Provided 644 CF Min elevatin void ratio - 0.3 I 1' min length 80 ft infiltration ° °: j rate= 20 in/hr o 0 o. 1 Qnul 0.19 ft3/sec ° 0 total volume 644 CF - 5.~' Bedding 2,00 Cover 2.0 ° ° Diameter 1.0 12 "pipe o Radius 0.5 ,o Width 5.0 ° Dill. from bottom of n~/n B Unil Volume UnilTrench Tofal Unit Tofal volume Trench of Pipe Volume Volume of trench 0.00 0 0.0000 0.000 0.000 0.000 0 0.10 0 0.0000 0.000 0.150 0.150 12 0.50 0 0.0000 0.000 0.750 0.750 60 1.00 0 0.0000 0.000 1.500 1.500 120 1.50 0 0.0000 0.000 2.250 2.250 180 2.00 0 0.0000 0.000 3.000 3.000 240 2.50 0.5 3.1416 0.393 3.632 4.025 322 3.00 1 6.2832 0.785 4.264 5.050 404 3.21 1.21 6.2832 0.785 4.579 5.365 429 3.35 1.35 6.2832 0.785 4.789 5.575 446 3.50 1.5 6.2832 0.785 5.014 5.800 464 4.00 2 6.2832 0.785 5.764 6.550 524 4.50 2.5 6.2832 0.785 6.514 7.300 584 > than the 100yr event, 549 CF 5.00 3 6.2832 0.785 7.264 8.050 644 Page 1 .~tati~g of 1~F.FATTT.T~ at- gtart of ri~n _ ( * May he rre~et by ~F:TI Command file C:\HYDRA\CMD~-05-0~9fi.CMD Input units are read as ~TSA * Output sent to display Detailed * Output sent to printer Brief * Output sent to file Detailed Paper width in inches 8.000 String to reset printer 27 51 36.18 String to set printer to compressed 17 15 String to set printer to 8 lines/inch 8 27 51 27 Name of printer Epson, FX series Print heading at top of page : False Number of _st.eps in h1rdrQgraph 96 Step length in minutes. 15 Significant .flow in hydrogr-aph : ~1.D1.0 * Maximum plot value Selected by HYDRA Type of hydragraphic plat Compae~t Sanitary-flow by Di'txrnal Curve Delay to start of actual stQr~r a.a~ Rational Method computations Off SCS computations Sarrta Barbara Continuous simulation computations C7ff * Maximum d/D for pipe design/analysis -~.9-00 * Match point position on pipe ~0:0`II or Invert * Number of allow-a7~le diam edraps ~~} * Mimimum drop thru manhole O.p-00 Routing te-chnique ~zick * Calculate sanitary flows Txue * Calculate infiltration flows 'Prue * Calculate storm flows 'Prue ~* Calculate misc flows True 1 .TC1R Valm C_a__r WacYi 7 (1(lVaar 7d ~Tnnr RF.M G-i ?e thF? i of i l teat i nn Gy~tem~ ~. J 4: TOT 4.00 _~• F _ RFM ti-mnntlh 1 _ 3~ irk, 7• RFM 1 ~~-vPar 4 (ln i n 8: 9 : FTT. rlc)e _ i T?~' "dal 1 c the dna iini t hydr~,g~aph ------TART (~F ~TTR-FTT.F.------ 1: HYE 10 0 00 040 0 040 0 0 04 tr ^~v 0 v v40 040 0 0 00 040 ^ 040 0 0 0 . . . . - . . . . . . . 40+ 2: 0.050 0 .050 0 .050 0 .05.n 0 .00 ~_ .n5_Q n _Otin 0. 050 n_ Qtin 0_ ..0_ti0 0, 050 0.050± ~. n non n non n non n non ~ non n non n nom n nom n nom n nom n nom J V.V/V V V/V VVlV V .ll fV _ .V-fV V". VY-V V-. VV-G VVVG V VVG V.VV"L V.VVL 0.082+ 4 : 0 _ 095 0 .0.95 0 .05_ n _0~5 0_ _n~~ n__ 0~5 Q _i ~4 0. 134. n _ ~ ~4 n _~ Rn_ 0. 180 0.340± ~. n inn ~ ~~n n ion n ion n ion n hen n noo n noo n boo ~ noo n noo J V J Z V . G r~v- v~. t-v v v. r /3 v~ . t ..rr V. t/-r v-. v vv V V v v -w . vv v V-v V V V V p 0.008+ 5: 0.088 0.088 O.ORB 0.088 O .ORB O.OR8 0.07? 0.07? 0. 072 0. 072 0 .072 0.072± 7: V. V 7 2 V. V 7 2 V. V 7 2 CnJ . V 7 G V . V~f G V. V 7 G V. V J7 V. V/ 7 V. V 57 V. V J 7 V . 0 5 7 0.057+ 8: 0.057 0.057 0.05.7 0__OF7 0. _0.57 2.057 0_OS~ 0.05n 0_ _00. 0__ 00 0 .050 n_ nnn+ J~ : V .050 V VSV- V . VJV - V'. VJ V' tnl VJV tnl. V1V - --V. V4"[n!- V' V-4 ~ V'. GTV- 0-. w4-V- V ~. V4V 0.040+ 10: 0.040 0.04.0 0.040. .n-_04n n _04n 0.04n 0_.0.4.0_ n_n4n n~ n4_:0. 0-__ ~4n 0. .040 0.040± ~~ n nnn n Cnn n nnn n nnn n nnn n nnn n nnn C nnn ra n4r~ n nnn n nnn 1 1. V. V T V V T V- V. V T-t! V• VTV V . VTV V. VTV V. VTV . VTV . V V. VTV V r V T V 0.040+ 12: 0.040 0.04.0 0_Q40 2__Q4.0 0 __040 0_040 0..040 0.04,n, 0_._ 0.4.0. 0~ n40 0 .040 n_ n4n~ 1J: V.V4V V.0.4V ----- - END OF SUB-FIL E ---- -- in 1 1 ; PTA Q _ n1~ R 1 7- 2 n __Q n~ ~ RPt R C~Pfal7~ ~ rl rP_ ZT~~ 7„1,P~ 1~ ; N_F.W C"ar W~ch ratrr~mnet and l an ~crari n~T 13: SCS 0.44 1.00 9 8 80 2 "'area;.. percent. i mpervious; CN i mpervi ous; Cn n arvi nn c T('' ~ 1 d ; RFC -1 Q /fl , 'I F QQQQgQ / Q , 'I ti A.QQ 1VVTE: 1YV f1 VVV tV / ~ 1111e4. 15 1 F ~ rTEy,;r Pr3.'Lratc l~nar7 17: CrC 0.5i 1.OOvgB'R0 lg; RFC -1 0/n,lg aggggg4gaga/p,ig NOTE: No flow to inlet. ~9- n • FnTn - - - ---- ______ a rr Trt nrt r p v n~ T TT T r v~ I c _ .~ v 1 a•1 1Z ~ t v- r 1Z-- rr- 1T sr- r v- Run number on command file T~Tiimhcr of l i nlrc Ni4mher pf h1rr~rnJrr~rhg _ Tnra1 rani Y~rlr =n=i~1 ati nn_ _, Total sanitarv area T_n_ta9 cYnrm araa N~imhE?rVnf r~mr~ _ TT~.~m1-,.-..r -.-.~ ~rr-. e+~-v-e rr+i v.e srt.retwc t vi s c oe t rv~~r• o- Number of diversion-structures ATnmhcr nf_ i n l ct c _ T.Pncrfih of Vnaw ni nP ----.~ --- - - --- •• r -r - T.Pnai-}-i of PXT Rr l nc7 nl nP ----a --- --- °--- ----.:r r -r - Lena_th of channel T.Pn Jrh. of c~~irtPr _ T.Pncrth of t-rancnnrfi iini fia ----~--- -- -------r--- ------- T.an~rh of =rPGG~ir~ ~i ~P :- 18 42 n 0.00 Acres n 7 0 n 0. 00 FPPt n- '-Qn F,'PPt 0.00 Feet 0 .On Feet 0 .00 Feet n _ Qn FPPt