The URL can be used to link to this page

Home My WebLink AboutFPA2008-00009 Erosion Control - FPA Plot / Site Plans - 8/15/20085 3 10 D_ SITE I� /IHi' LOOP ROAD i- goo°<.` 13 7 18 • I STRECH 8 ISLAND HS 22 23 24 j HARSTENE li ISLAND .- VICINITY M A P N.T.S. SHEET INDEX SHEET 1 OF 4 COVER SHEET AND LAYOUT SHEET 2 OF 4 EROSION CONTROL DETAILS SHEET 3 OF 4 CONTRUCT/ON AND EROSION CONTROL NOTES SHEET 4 OF 4 STORMWATER / EROSION CONTROL NOTES LEGEND ROCK CHECK DAM FILTER FABRIC FENCE DIRECTION OF SURFACE WATER FLOW CATEGORY 111 WETLAND EROSION AND STORMWATER CONTROL FOR ERIC J. & JA NA PERS S ON FOREST PRACTICES SECTION 7, TOWNSHIP 21 NORTH, RANGE I WEST, WM. PARCEL # 12107-75-00050 COVER SHEET AND PROPERTY LAYOUT PARCEL # 121077500050 CATEGORY III WETLAND 60' BUFFER PLUS 15' BUILDING SETBACK 200' 1 G L RA RD n 300' -VIEW L 0 3:1 VARIABLE 8' FLAT BOTTOM 3:I - 7.5' 1' 3:1 - VARIABLE FLAT BOTTOM DITCH FOR WEST BASIF - CRASS SECTIONAL VIEW CHECK DAMS FOR WEST BASIN - END VIEW 3:1 - VARIABLE 10- 711- vorilVar ow 1YT MAXIMUM HEIGHT OF STORMWATER 100 YR STORM CHECK DAMS FOR WEST BASIN - CROSS SECTIONAL VIEW 8' FLAT BOTTOM 2 5' FLAT BOTTOM DITCH FOR EAST BASIN - CROSS SECTIONAL VIEW 8' MAXIMUM HEIGHT OF S I URMWATER 100 YR STORM CHECK DAMS FOR EAST BASIN CROSS SECTIONAL VIEW 3:1 VARIABLE 4' ea aIs s s sue W CHECK DAMS FOR EAST BASIN - END VIEW r-9 z 0 LAYOUT OF SLAT BOTTOM DITCH WITH RACK CHECK DAMS Z TOE 2 1 21' TO 4-" QUARRY SPALLS L SPACING BETWEEN CHECK DAMS - THE TOP AND TOE ARE THE SAME ELEVATION ROCK CHECK DAMS IN DITCH N.T.S. TOP ) 2 1 el3Jdna JO 39Q3 EROSION AND S TORM WA TER CONTROL FOR ERIC J. & JANA PERS S ON FOREST PRACTICES SECTION 7, TOWNSHIP 21 NORTH, RANGE 1 WEST, WM. PARCEL # 12107-75-00050 EROSION CONTROL DETAILS 2" x 4ff x 14 GA WELDED WIRE FABRIC OR EQUAL 2 "x 2'x 5' DOUGL AS FIR STAKE AT 6'-6" MAX. D.C, (TYP,) CONSTRUCTION GEDTEXTILE FOR TEMPORARY SILT FENCE 2' x 4' x 14 GA WELDED WIRE FABRIC DR EQU In EVAI1KWgi�7�7I1��r71��i1��r�Al A7�77��7�i•7�-��iAMA LIMY�i�7�i��j��i�7��JTRVATAM aterAVAVAYy��y��VALTAWA��Q�� I-��VM ��0VOL tY��►1 WA •0000000000000V000000000000'000000o•-yo /��/�%!�/�� \/%ice/��\\\\/ ��%�\f\,:/: /� \\/f\/?-fi ELEVATION i 8'x 12' TRENCH CONSTRUCTION GEL] TEX TIL E FOR TEMPORARY SILT FENCE 1 1/2" MINUS WASHED ROCK SILT LADEN 8"x 12' TRENCH FLOW NOTES; 2" EXCESS L7 VERL AP- 8'--- TYPICAL CROSS—SECTION 1) SEE STANDARD SPECIFICA ION 2-12.3(5), 2) STEEL POSTS MAY BE USED: SUPPORTED BETWEEN POSTS /VITH NIRE FILTER FABRIC FENCE N.T.S. 12" MIN. DEPTH 4" TO 8" QUARRY SPALLS PROVIDE FULL WIDTH OF INGRESS/EGRESS AREA STABILIZED CONTRUCTION ENTRANCE O co �w 0) °' C5 �W J r"CT) zx N CO ciLu O. r- v Lj u. _ O f GENERAL NOTES: 1. ALL APPROVALS AND PERMITS REQUIRED BY THE COUNTY SHALL BE OBTAINED BY THE CONTRACTOR PRIOR TO THE START OF CONSTRUCTION 2. THE CONTRACTOR SHALL BE FULLY RESPONSIBLE FOR THE LOCATION AND PROTECTION OF ALL EXISTING UTILITIES. THE CONTRACTOR SHALL VERIFY THE LOCATIONS PRIOR TO CONSTRUCTION B.Y CALLING THE UNDERGROUND LOCATE LINE AT 1-800-424-5.55.5 A. MINIMUM OF 48 HOURS PRIOR TO ANY EXCAVATION. 3. THE CONTRACTOR IS RESPONSIBLE FOR INSTALLING ANY BURIED UTILITIES AND ELECTRICAL LINES TO APPLICABLE CODES. 4. ALL WORKMANSHIP AND MATERIALS SHALL BE IN ACCORDANCE WITH MASON COUNTY STANDARDS AND THE MOST CURRENT COPY OF THE STATE OF WASHINGTON STANDARD SPECIFICATIONS FOR ROAD BRIDGE AND MUNICIPAL CONSTRUCTION (WSDOT/APWA. 5. ALL SURVEYING AND CONSTRUCTION STAKING SHALL BE PERFORMED) BY AN ENGINEERING OR SURVEYING FIRM CAPABLE OF PERFORMING SUCH WORK. THE ENGINEER OR SURVEYOR DIRECTING SUCH WORK SHALL BE LICENSED BY THE STATE OF WASHINGTON. 6. WHEN PROJECT IS COMPLETE CONTRACTOR SHALL LEAVE THE SITE IN A NEAT AND - PRESENTABLE CONDITION, CLEAR OF DIRT AND/OR DEBRIS. 7. THE CONTRACTOR SHALL BE RESPONSIBLE FOR PROVIDING ADEQUATE SAFEGUARDS, SAFETY DEVICES, PROTECTIVE EQUIPMENT, FLAGGERS, AND ANY OTHER NEEDED ACTIONS TO PROTECT THE LIFE, HEALTH, AND SAFETY OF THE PUBLIC AND TO PROTECT PROPERTY IN CONNECTION WITH THE PERFORMANCE OF WORK COVERED BY THE CONTRACTOR. ANY WORK WITHIN THE TRAVELED RIGHT-OF-WAY THAT MAY INTERRUPT NORMAL TRAFFIC FLOW SHALL REQUIRE AT LEAST ONE FLAGGER FOR EACH LANE OF TRAFFIC AFFECTED. ALL SECTIONS OF THE WSDOT STANDARD SPECIFICATIONS 1-07.23-TRAFFIC CONTROL SHALL APPLY. 8. THE CONTRACTOR SHALL NOTIFY THE PROJECT ENGINEER IN THE EVENT OR DISCOVERY OF POOR DRAINING SOILS, STANDING GROUNDWATER, OR_ SEVERE DISCREPANCIES FROM SOIL INFORMATION AS ORIGINALLY REVIEWED. CONSTRUCTION NOTES COMPACTION OF ALL FILL AREAS SHALL BE PER CURRENT WSDOT/APWA SPECIFICATIONS. FILL SHALL BE PROVIDED IN 8" MAXIMUM LIFTS AND SHALL BE COMPACTED TO 95 PERCENT OF ITS MAXIMUM RELATIVE DENSITY. CULVERTS: IF NECESSARY HANCOR HiQ - DOUBLE -WALLED, CORRUGATED, POLYETHYLENE PIPE, WITH A SMOOTH INTERNAL DIAMETER (AASHTO M-294 TYPE-S ADS N-12 PLASTIC PIPE 12"-24" 0 ONLY) OR APPROVED EQUAL_ COUPLED WITH A COMPANY -PRODUCED PVC COUPLING OR APPROVED EQUAL. EROSION AND STORMWATER CONTROL FOR ERIC J. & JANA PERSSON FOREST PRACTICES SECTION 7, TOWNSHIP 21 NORTH, RANGE I WEST, WM. PARCEL # 12107-75-00050 CONSTRUCTION AND EROSION CONTROL NOTES EROSION AND SEDIMENT CONTROL REQUIREMENT: THIS THINNING PROJECT WILL DISTURB APPROXIMATELY 7.6 ACRES. PER THE DOE STORMWATER MANAGEMENT MANUAL - ALL NEW DEVELOPMENT THAT INCLUDES TF-fE CREATION OR ADDITION OF 5,000 SQUARE FEET, OR GREATER, OF NEW IMPERVIOUS SURFACE AREA, AND / OR LAND DISTURBING ACTIVITY OF ONE ACRE OR GREATER, SHALL COMPLY WITH THE MINIMUM REQUIREMENTS #1 THROUGH #11. 1. WHERE APPLICABLE, THIS PROJECT SHALL COMPLY WITH LARGE PARCEL EROSION AND SEDIMENT CONTROL REQUIREMENTS 1 THRU 11 FOUND IN SECTION 1-2.5 OF THE WASHINGTON STATE DEPARTMENT OF ECOLOGY STORMWATER MANGEMENT MANUAL FOR THE PUGET SOUND' BASIN (THE TECHNICAL MANUAL ). 2. WHEN NECESSARY THE PRIVATE CONSTRUCTION VEHICLE ACCESS SHALL BE MAINTAINED TO COMPLY WITH EROSION AND SEDIMENT CONTROL REQUIREMENTS FOUND IN THE WASHINGTON STATE DEPARTMENT OF ECOLOGY 'MANUAL'. IF A POTENTIAL FOR TRACKING MUD AND DEBRIS -OCCURS, THE CONTRACTOR SHALL IMMEDIATELY ELIMINATE THE POTENTIAL. 3. CONSTRUCTION VEHICLE ACCESS SHALL BE, WHENEVER POSSIBLE, LIMITED TO ONE ROUTE. ACCESS POINTS,WHEN NECESSARY, , SHALL. BE STABILIZER TO._ MINIMIZE . THE TRACKING OF SEDIMENT ONTO PUBLIC HIGHWAYS. WHENEVER CONSTRUCTION VEHICLE ACCESS ROUTES INTERSECT PAVED STREETS, PROVISION MUST BE MADE TO MINIMIZE THE TRANSPORT OF SEDIMENT ONTO THE PAVED STREET. IF SEDIMENT IS TRANSPORTED ONTO A STREET, THE STREET SHALL BE CLEANED IMMEDIATELY, AND THOROUGHLY CLEANED AT THE END OF EACH DAY. 4. SEDIMENT TRAPS, SEDIMENT BARRIERS. AND. OTHER BMP'S INTENDED TO TRAP SEDIMENT ON SITE SHALL BE CONSTRUCTED AS NECESSARY. STANDARD STORMWATER NOTES: 1. A COPY OF THESE APPROVED STORMWATER PLANS MUST BE ON THE JOB SITE WHENEVER CONSTRUCTION IS IN PROGRESS. 2. THE STORM DRAINAGE SYSTEM SHALL BE CONSTRUCTED ACCORDING TO THESE APPROVED PLANS ON FILE WITH THE COUNTY. ANY SIGNIFICANT DEVIATION FROM THESE APPROVED PLANS WILL REQUIRE WRITTEN APPROVAL FROM THE COUNTY. 3. IN ANY AREA WHICH HAS BEEN STRIPPED OF VEGETATION OR EXPERIENCFI)_ LAND._ DISTURBING. ACTIVITIES AND WHERE NO FURTHER WORK IS ANTICIPATED FOR A PERIOD EXCEEDING THE LISTED CRITERIA BELOW, ALL DISTURBED AREAS MUST BE IMMEDIATELY STABILIZED WITH MULCHING, GRASS PLANTING, OR OTHER APPROVED EROSION CONTROL TREATMENT APPLICABLE TO THE TIME OF YEAR IN QUESTION. GRASS SEEDING ALONE WILL BE ACCEPTABLE ONLY DURING THE MONTHS OF APRIL THROUGH SEPTEMBER, INCLUSIVE.- SEEDING- MAY PROCEED, HOWEVER, WHENEVER IT IS IN. THE INTEREST OF THE DEVELOPER/CONTRACTOR, BUT MUST BE AUGMENTED WITH MULCHING, NETTING, OR OTHER TREATMENT. 4. ALL EROSION CONTROL AND STORMWATER FACILITIES SHALL BE REGULARLY INSPECTED AND MAINTAINED BY THE CONTRACTOR DURING THE CONSTRUCTION PHASE OF THE DEVELOPMENT PROJECT. THE FOLLOWING SHALL BE ADHERED TO ON ALL CONSTRUCTION SITES WITH EROSIVE SOILS AND/OR A GRADIENT OF GREATER THAN 2 PERCENT FOR LIMITING EXPOSED- SOILS TO EROSIVE PROCESSES. MAY 1 TO SEPTEMBER 30 (DRY SEASON) THE CLEARING OF LAND, INCLUDING THE REMOVAL- OF EXISTING VEGETATION OR OTHER GROUND- COVER, MUST BE LIMITED TO ONLY AS MUCH LAND AS CAN RECEIVE APPROPRIATE PROTECTIVE COVER OR BE OTHERWISE STABILIZED, AFTER HAVING BEEN CLEARED OR OTHERWISE DISTURBED, BY NO LATER THAN SEPTEMBER 30 OF A GIVEN YEAR. UNLESS IMMEDIATE STABILIZATION IS SPECIFIED IN THE EROSION AND SEDIMENTATION CONTROL PLAN, ALL AREAS CLEARED OR OTHERWISE DISTURBED MUST BE APPROPRIATELY STABILIZED THROUGH THE USE OF MULCHING, NETTING, PLASTIC SHEETING, EROSION BLANKETS, FREE DRAINING MATERIAL, ETC., BY SEPTEMBER 30 OR SOONER PER THE APPROVED PLAN OF ACTION. UNLESS OTHERWISE APPROVED BY THE COUNTY, SEEDING, FERTILIZING, AND MULCHING OF CLEARED OR OTHERWISE DISTURBED AREAS SHALL BE PERFORMED DURING THE FOLLOWING PERIODS: MARCH 1 TO MAY 15 AND AUGUST 15 TO OCTOBER 1. SEEDING AFTER OCTOBER 1 WILL BE DONE WHEN PHYSICAL COMPLETION OF THE PROJECT IS IMMINENT AND THE ENVIRONMENTAL CONDITIONS ARE CONDUCIVE TO SATISFACTORY GROWTH. IN THE EVENT THAT PERMANENT STABILIZATION IS NOT POSSIBLE, AN ALTERNATIVE METHOD OF GROUND COVER (SUCH AS MULCHING, NETTING, PLASTIC SHEETING, EROSION BLANKETS, ETC.) MUST BE INSTALLED BY NO LATER THAN SEPTEMBER 30. IN THE EVENT THAT CONSTRUCTION ACTIVITIES OR OTHER SITE DEVELOPMENT ACTIVITIES ARE DISCONTINUED FOR 4 CONSECUTIVE DAYS OR MORE, THE PROPONENT SHALL BE RESPONSIBLE FOR THE INSPECTION OF ALL EROSION AND SEDIMENTATION CONTROL FACILITIES. IMMEDIATELY AFTER STORM EVENTS, AND AT LEAST ONCE EVERY WEEK. THE PROPERTY OWNER SHALL BE RESPONSIBLE FOR THE MAINTENANCE AND REPAIR OF ALL EROSION AND SEDIMENTATION CONTROL FACILITIES. OCTOBER 1 TO APRIL 30 (WET SEASON) ON SITES WHERE UNINTERRUPTED CONSTRUCTION ACTIVITY IS IN PROGRESS, THE CLEARING OF LAND, INCLUDING THE REMOVAL OF EXISTING VEGETATION OR OTHER GROUND COVER, SHALL BE LIMITED TO ONLY AS MUCH LAND AREA AS CAN BE COVERED OR STABILIZED WITHIN 24 HOURS IN THE EVENT A MAJOR STORM IS PREDICTED AND/OR EROSION/ SEDIMENT TRANSPORT OFF -SITE IS OBSERVED. ADDITIONALLY, ALL CLEARED OR DISTURBED AREAS WILL RECEIVE APPROPRIATE PROTECTIVE COVER OR BE OTHERWISE STABILIZED (SUCH AS MULCHING, NETTING, PLASTIC SHEETING, EROSION BLANKETS, FREE DRAINING MATERIAL, ETC.) WITHIN 5 DAYS AFTER HAVING BEEN CLEARED OR OTHERWISE DISTURBED IF NOT BEING ACTIVELY WORKED. FILTER FABRIC- FENCING, SEDIMENT TRAPS, SEDIMENT PONDS, ETC., WILL NOT BE VIEWED AS ADEQUATE COVER IN AND OF THEMSELVES. IN THE EVENT THAT ANY LAND AREA NOT BEING ACTIVELY WORKED REMAINS UNPROTECTED OR HAS NOT BEEN APPROPRIATELY STABILIZED 5 DAYS AFTER HAVING BEEN CLEARED, ALL CONSTRUCTION ACTIVITY ON THE SITE, EXCEPT FOR APPROVED EROSION AND SEDIMENTATION CONTROL ACTIVITY, SHALL IMMEDIATELY CEASE UNTIL SUCH A TIME AS SAID LAND AREA HAS BEEN APPROPRIATELY PROTECTED OR STABILIZED. THE CONTRACTOR SHALL AT ALL TIMES HAVE AVAILABLE FOR THE PROJECT SUFFICIENT QUANTITIES OF PROTECTIVE COVERING MATERIALS TO IMMEDIATELY STABILIZE ALL DISTURBED AREAS IN CASE THE PROJECT ENGINEER OR COUNTY DIRECTS HIM/HER TO COVER DUE TO OBSERVED MIGRATION OF SOILS OR INCLEMENT WEATHER, (REFER TO EROSION CONTROL NOTES #5). EROSION CONTROL NOTES: 1. THIS SITE DOES NOT HAVE A STABILIZED ENTRANCE. A TEMPORARY CONSTRUCTION ENTRANCE AS PER THE D.O.E. MANUAL IS REQUIRED. THE STABILIZED CONSTRUCTION ENTRANCE DETAIL IS SHOWN ON THESE CIVIL DRAWINGS. THE SITE LOCATION TO BE DETERMINED BY THE CONTRACTOR. 2. SHOULD THE NATURAL EROSION AND SEDIMENTATQN CONTROL MEASURES NOT PROVE ADEQUATE TO CONTROL EROSION AND SEDIMENTATION, THE DEVELOPER/CON-TRACTOR SHALL INSTALL ADDITIONAL FACILITIES AS. NECESSARY TQ PROTECT ADJACENT PROPERTIES, SENSITIVE AREAS, AND/OR THE STORM DRAINAGE SYSTEM. 3. THE PROPOSEDCLEARING LIMITS -FOR THE PROPOSED THINNING SHALL BE DEFINED BY THE OWNER OR THEIR- ASSIGNS. FLAGGING OR OTHER IDENTIFICATION MAY BE USED. THE BUFFER LIMITS SHALL ALSO BE CLEARLY MARKED WITH FLAGGING. 4. THE CONTRACTOR SHALL PROVIDE MATERIALS ON -SITE READILY AVAILABLE TO IMMEDIATELY STABILIZE DENUDED AREAS DURING PERIODS OF INCLEMENT WEATHER WHICH RESULT IN EROSION AND SFDIMENT TRANSPORT OFF -SITE. AS A MINIMUM THE CONTRACTOR SHALL HAVE ON HAND 30 STRAW HAY BALES AND FOUR (20 FT. BY 100 FT.) ROLLS OF 6 MIL PLASTIC COVERING. 5. ALL WORK ASSOCIATED WITH STABILIZING THE. DISTURBED AREASSHALLBE. IN ACCORDANCE WITH THE MASON COUNTY STORMWATER MANAGEMENT MANUAL. 6. ALL NECESSARY FACILITIES SHALL BE MAINTAINED ON SITE TO PREVENT DEBRIS, DUST, AND MUD FROM ACCUMULATING ON PUBLIC OR PRIVATE PROPERTY OR RIGHT OF WAY. SILT FENCES 1. FILTER FABRIC SHALL BE PURCHASED IN A CONTINUOUS ROLL AND CUT TO THE LENG.TH. OF THE BARRIER TQ AVOID. USE OF JOINTS. WHEN JOINTS ARE NECESSARY, FILTER CLOTH SHALL BE SPLICED TOGETHER ONLY AT A SUPPORT POST WITH A MINIMUM 6-INCH OVERLAP, AND SECURELY FASTENED AT BOTH ENDS TO POSTS 2. POSTS SHALL BE SPACED A MAXIMUM OF 6 FEET APART AND DRIVEN SECURELY INTO THE GROUND (MINIMUM OF 30 INCHES) . 3. A TRENCH SHALL BE EXCAVATED APPROXIMATELY 8 INCHES WIDE AND 12 INCHES DEEP ALONG- THE LINE OF POSTS AND UPSLOPE FROM THE BARRIER. THIS TRENCH SHALL BE BACKFILLED WITH WASHED GRAVEL. 4. WHEN STANDARD STRENGTH FILTER FABRIC IS USED, A WIRE MESH SUPPORT FENCE SHALL BE FASTENED SECURELY TO THE UPSLOPE SIDE OF THE. POSTS USING HEAVY-DUTY WIRE. STAPLES AT LEAST 1-INCH LONG, TIE WIRES_ OR HOG RINGS__ THE WIRE SHALL EXTEND INTO THE TRENCH A MINIMUM OF 4 INCHES AND SHALL NOT EXTEND MORE THAN 24 INCHES ABOVE THE ORIGINAL GROUND SURFACE. 5. THE STANDARD STRENGTH FILTER FABRIC SHALL BE STAPLED OR WIRED TO THE FENCE, AND 20 INCHES OF THE FABRIC SHALL BE EXTENDED INTO THE TRENCH. THE FABRIC SHALL NOT EXTEND MORE THAN 24 INCHES ABOVE THE ORIGINAL GROUND. SURFACE. 6. WHEN EXTRA -STRENGTH FILTER FABRIC AND CLOSER POST SPACING IS USED, THE WIRE MESH SUPPORT FENCE MAY BE ELIMINATED. IN SUCH A CASE, THE FILTER FABRIC IS STAPLED OR WIRED DIRECTLY TO THE POSTS WITH ALL OTHER PROVISIONS OF ABOVE NOTES APPLYING. 7. FILTER FABRIC FENCES SHALL NOT BE REMOVED BEFORE THE UPSLOPE AREA HAS BEEN PERMANENTLY STABILIZED. 8. FILTER FABRIC FENCES SHALL BE INSPECTED IMMEDIATELY AFTER EACH RAINFALL AND AT LEAST DAILY DURING PROLONGED RAINFALL. ANY REQUIRED REPAIRS SHALL BE MADE IMMEDIATELY. 9. SILT FENCES WILL BE INSTALLED PARALLEL TO ANY SLOPE CONTOURS. 10. INSTALL DOWNSLOPE OF EXPOSED AREAS. 11. DO NOT DRIVE OVER OR FILL OVER SILT FENCES. SEEDING - FOR ALL RAWSLOPES: 1. SEED MIXTURE SHALL BE AS SHOWN BELOW, AND SHALL BE APPLIED AT THE RATE 2. SEED BEDS PLANTED- BETWEEN MAY 1 AND OCTOBER 31 WILL REQUIRE IRRIGATION TO FOSTER AND PROTECT THE ROOT STRUCTURE. 3. FOR SEED BEDS PLANTED BETWEEN OCTOBER 31 AND APRIL 30, ARMORING OF THE GEOTEXTILES, JUTE MAT,CLEAR PLASTIC COVERING), 4. BEFORE SEEDING, INSTALL NEEDED SURFACE RUNOFF CONTROL MEASURES SUCH AS GRADIENT TERRACES, INTERCEPTOR DIKES, SWALES, LEVEL SPREADERS AND SEDIMENT BASINS. 5. THE SEEDBED SHALL BE FIRM WITH FAIRLY FINE SURFACE, FOLLOWING SURFACE ROUGHENING. PERFORM ALL OPERATIONS ACROSS OR AT RIGHT ANGLES TO THE SLOPE. 6. FERTILIZERS ARE TO BE USED ACCORDING- TO SUPPLIERS' RECOMMENDATIONS. AMOUNTS USED SHOULD BE MINIMIZED, ESPECIALLY ADJACENT TO WATER BODIES AND WETLANDS. OF 120 POUNDS PER ACRE. AND -OTHER MAINTENANCE AS NECESSARY SEED BED WILL BE NECESSARY, (e.g., USE THE FOLLOWING RECOMMENDED SEED MIXTURE FOR EROSION CONTROL, OR A COUNTY -APPROVED ALTERNATE SEED MIXTURE, Name Proportions Percent Percent by Weight Purity Germination Redtop (Agrostis alba) 4nnuat rye (Lotium r ultiflorun-) Chewing fescue (Festuco. rubra commutate) (James-taw-n, Banner, Shool w, or Koket) White dutch ctove-r (Trifoliurn repens) 10 percent 40 percent 40 percent 10 percent 98 98 97 90 90 80 96 90 MULCHING - FOR ALL RAW SLOPES: 1. MULCH MATERIALS USED SHALL BE WOOD FIBER CELLULOSE, AND SHALL BE APPLIED AT THE RATE OF 1000 POUNDS PER ACRE 2. MULCH SHALL BE APPLIED IN ALL AREAS WITH EXPOSED SLOPES GREATER THAN 2: 1. 3. MULCHING SHALL BE USED IMMEDIATELY AFTER SEEDING OR IN AREAS WHICH CANNOT BE SEEDED BECAUSE OF THE SEASON 4. ALL AREAS NEEDING MULCH SHALL BE COVERED BY NOVEMBER 1. z W z o Qoccct = Q z �z0w CC U-1 w�� Q a er w� a L Z::, Z W O OOP.: CL'Z= ( O U :. v z � o FOREST PRACTICES APPLICATION STORMWATER/EROSION CONTROL REVIEW I. PROJECT OVERVIEW ERIC AND JANA PERSSON OWNERS OF 10 ACRES - The Forest Practices Application is for the thinning of timber from their property located in Section 7, T. 21 N., R. 1 W., W.M., Parcel No. 12107 75 00050. Landowner wishes to conduct an uneven aged and salvage type harvest to ensure proper crown spacing and to reduce pockets of disease and defects. An improved gravel access road serves the site. Removal is to be completed using rubber tired skidder. This project is located in an area designated by Mason County as Rural, at the intersection of East Murray Road North and East Frontier Road. Topography wi#rin the property slopes down toward a wide, law gradient swale that slopes southwesterly within the central portion of the parcel. A forested wetland is located within the swale. The Wetland Delineation Report states that the wetland meets criteria for a Slope wetland based on functions per Washington State Wetland Rating System for Western Washington (Hruby 2004) for the purposes of rating. Based on functional attributes associated with the wetland including habitat, water quality, and hydrology functions, it has been rated as a Category I11 wetland. According to Table 17.01.070 D of the Mason County Resource Ordinance the base buffer width is required to be 60 feet in width with an additional 15 foot building setback. Generally there are no steep slopes (5-- 15 percent) or saturated conditions that would lead to sflding. The natural swale separates the property into two drainage basins. The easterly basin contains approximately 5.53 acres and the westerly basin contains approximately 4.47 acres. The runoff from each basin will be captured by its own constructed flat bottomed ditch with check dams that will run parallel to the natural swale, and 10 feet away from the wetland buffer. The constructed flat bottomed ditch with check dams will act as a settling pond, a treatment facility and some infiltration before the stormwater reaches the natural swate and the Category 111 wetland. The calculated additional post stormwater runoff caused by the thinning will infiltrate into the ground. Post storm runoff will be Tess than Pre storm runoff. The soil survey of Mason County indicates that the one onsite soil type, (USDA1951) is Alderwood gravelly sandy loam (Ab), 5 to 15 percent slopes. The Alderwood series consists of brown, well -drained, upland soils. They have developed from mixed gravelly glacial till dominated by acid igneous rock. The imbedded gravel is mainly granite and quartzite. Rainfall is 45 to 60 inches a year. The native vegetation is dense forest consisting almost entirely of Douglas -fir and a dense understory of salal, Oregon -grape, vine maple, and huckleberry. Northeast of the Hood Canal the understory is mainly rhododendron. Alderwood soils occupy extensive rolling glacial moraines, and they are the dominant soils in the eastern part of the county. The Alderwood soils are associated with the somewhat excessively drained Everett and lnianola soils and with the moderately well drained Vitsap soils. The Alderwood gravelly sandy loam, 5 to 15 percent slopes (Ab) is the most extensive soil of the Alderwood series. It occupies undulating to rolling moraines. Alderwood gravelly sandy loam, 5 to 30percent slopes. (Ac). This soil varies more in depth, but otherwise it is similar. to Alderwood gravelly sandy loams, 5 to 15 percent slopes. Experience has shown that the infiltration rate for this soil is: 4.3 inches per hour. MINIMUM REQUIREMENTS The project shall comply with D.O.E's 1992 Stormwater Management Manual for the Puget Sound Basin, New Development Minimum Requirements #1 through #11. Minimum Requirement #1: EROSION AND SEDIMENT CONTROL Refer to EROSION and SEDIMENT CONTROL PLAN DURING THE TIMBER THINNING located on this sheet_ Minimum Requirement #2: PRESERVATION OF NATURAL DRAINAGE SYSTEMS Natural drainage patterns shall be maintained, and discharges from the site shall occur at the natural location,. to the maximum extent practicable. There is one drainage swale that separates the property into twa drainage basins. i-he drainage swale has been classified as a Category III wetland with a 50 foot buffer. The logging operation will not disturo the wetland nor the buffer. Wide bottom ditches with check dams will be constructed parallel to and on each side of the wetland buffer. These ditches will capture the runoff before it reaches the wetland. The Post runoff is calculated to be Tess than the Pre runoff, therefore, this proposed logging will not alter the natural drainage patterns off site. Minimum Requirement #3: SOURCE CONTROL OF POLLUTION * Source control BMPs shall be applied to all projects to the maximum extent practicable. Source control BMPs shalt be selected, designed, and maintained according to an approved manual: The 10 acres is divided into 2 drainage basins. Each basin borders the Category III wetland 60' buffer. A filter fabric fence will be installed adjacent to the buffer in each basin. Adjacent to the filter fabric fence a fiat bottomed ditch with check dams will be constructed. The ditch with check dams will act as a settling pond, a treatment facility and also provide infiltration before the stormwater reaches the natural swale. Minimum Requirement #4: RUNOFF TREATMENT BIVFPS * First priority for treatment shall be to infiltrate as much runoff as possible, if site conditions are appropriate and ground water quality will not be impaired. In addition to the treatment received from the flat bottomed ditch, the runoff treatment will also be primarily the natural treatment received from overland flow and the infiltration in each basin. Minimum Requirement #5: STREAMBANK EROSION CONTROL * This requirement applies only to situations where stormwater runoff is discharged to a stream. Calculations show that the Post runoff satisfies the Streambank Erosion Control requirements. Minimum Requirement #6:. WETLANDS * This requirement applies only to situations where stormwater discharges directly or indirectly through a conveyance system into.a wetland.. This project is Timber Thinning. This project will not change the amount of pervious surface. Minimum Requirement #7: WATER QUALITY SENSITIVE AREAS * Where local governments determine that the Minimum Requirements do not provide arIr rji ate protection of water quality sensitive areas, either on -site or within the basin, more stringent controls shall be required. Mason County has not imposed additional requirements. Minimum Requirement #8: OFF -SITE ANALYSIS AND MITIGATION * All development projects shall conduct an analysis of off -site water quality impacts resulting from the project and shall mitigate these impacts.. The analysis shall extend a minimum of one-fourth of a mile downstream from the project. The off site Post Discharge is calculated to be less than the Pre Discharge. Further analysis is not necessary. Minimum Requirement #9-: BASIN PLANNING- * An adopted and implemented basin plan may be used to develop requirements for water quality sensitive areas that are tailored to a specific basin. The proposed project is addressing stormwater issues with on -site facilities. No water -shed basin plan is available for use. Minimum Requirement #1-0; OPERATION AN[ MAINTENANCE DURING LOGGING * An operation and maintenance schedule shall be required for all proposed stormwater facilities and BMPs, and the party (or parties) responsible for maintenance and operation shall be identified. The private facility maintenance checklist should be tailored to the facility. The Owner/Contractor will be responsible for operation and maintenance of any stormwater facilities during and after the Timber Thinning. The Owner/Contractor will also inspect the facilities for any evidence of erosion or soil migration and take appropriate action. Grass should ba encouraged to grow where fogging has been completed. Some timber and native brush will remain behind to assist in greenup. Some areas may be replanted with douglas fir seedlings. Minimum Requirement #11: FINANCIAL RESPONSIBILITY * Performance bonding or other appropriate financial instruments shall be required for all projects to ensure compliance with these standards. We do not expect Mason County to make any requirements regarding performance bonding as a result of the stormwater control plan. 1I. PLOT PLAN See Civil Drawings III. GENERAL SITE CONDITIONS SUMMARY See Project Overview for information. IV. SPECIAL REPORTS AND STUDIES A Wetland Delineation Report,prepared by "THE WETLAND CARPS" is. attached to these Civil Drawings V. BASIN AND COMMUNITY PLANNING N/A Vi. STORM EVENT DESIGN ASSUMPTIONS STORMWATER CONTROL REVIEW Based on DOE's Stormwater Management Manual: * STORM EVENT Total Acreage East basin West basin Rain Precipitation (in.) Six-month, 24-hour Storm Event Two-year, 24-hour Storm Event Ten-year, 24-hour Storm Event Hundred -year, 24-hour Storm Event Rainfall Choice Hydrograph ** Santa Barbara Urban Hydrograph Method 10 acres 5.53 ac 4.47 ac 2.24" 3.50" 4.75" 6.50" IA SBUH** EROSION AND STORMWATER CONTROL FOR ERIC J. & JANA PERSSON FOREST PRACTICES SECTION 7, TOWNSHIP 21 NORTH, RANGE ? WEST, WM. PARCEL # 12107-75-00050 S TORMWA TER I EROSION CONTROL REPORT EROSION and SEDIMENT CONTROL PLAN DURING THE TIMBER HARVESTING #1 Stabilization and Sediment Trapping All exposed and unworked soils shall be stabilized by suitable application of BMPs. From October 1 to April 30, no soils shall remain unstabilized for more than 2 days. From May 1 to September 30, no soils shall remain unstabilized for more than 7 days_ Prior to leaving the site, stormwater runoff shall pass through a sediment pond or sediment trap, or other appropriate BMP's. The proposed thinning and harvesting will be with rubber tired skidder. Harvested area boundaries include the 10 acre area. All exposed soil will be seeded`. A filter fabric fence shall be installed on each side of the buffer. A flat bottom ditch will be installed to act as a settling trap, a tredlnrentfacility and an infiltration pond. #2 Delineate Clearing and Easement Limits In the field, mark clearing limits and/or any eassements, setbacks, sensitive/critical areas and their buffers, trees and drainage cources. The thinning and harvesting operations take place on the entire 10 acres. Delineation of the property boundaries and the boundaries of the wetland buffer are required. Strips of ribbon will be adequate. #3 Protection of Adjacent Properties Property adjacent to the project site shall be protected from sediment deposit. The underlying soils are considered to have very little potential for migration. Protecting adjacent property (beyond Persson's ownership) from damage caused by sedirrrentmigralion does not appear to be a problem. Filter fencing (BMP E3.10) will be installed adjacent to the wetland area. Hay or grass mulch maybe used where necessary. #4 Timing and Stabilization of Sediment Trapping Measures Sediment ponds and traps, perimeter dikes, sediment barriers, and other BMP's intended to trap sediment on -site shall be constructed as a first step in grading. The proposal is a Timber Thinning, with ground disturbance to be kept at a minimum. The underlying soils are considered to have very little potential for migration. The filter fabric fence will be installed to protect the wetland and buffer. The flat bottom ditch will be installed to act as a sediment trap, treatment facility and infiltration pond. The Contractor shall provide material on -site readily available to immediately stabilize problem areas during periods of inclement weather. As a minimum the Contractor shall have on hand 30 straw/hay bales and 4 (20 ft. by 100 f_) rolls. of 6 mil plastic covering. Erosion control measures are to be installed first before any significant Timber Thinning is started. #5 Cut and Fill Slopes Cut and fill slopes shall be designed and constructed in a. manner that will minimize erosion. The Timber Thinning activities do not generate Cut and Fill Slopes. However, the installation of the flat Bottom. Ditchwill havecut and fill slopes_ The side slopes of. the ditch are to be no steeper than 3 foot horizontal to 1 foot horizontal. All raw ditch slopes shall be seeded and or mulched immediately after construction- #6 Controlling Off -site Erosion Properties and waterways downstream from development sites shall be protected from erosion due to increases in volume, velocity, and peak flow irate of stormwater runoff from the project site. Because of the gravelly nature of the existing materials, off -site erosion is not anticipated to become an issue. Also the calculated post discharge is less than the calculated pre discharge because of infiltration expected in the flat bottom ditch. #7 Stabilization of Temporary Conveyance Charnels and Outlets All temporary on -site conveyance channels shall be designed, constructed and stabilized to prevent erosion from the expected velocity of flow -from the 2-year, 24-hour frequency scram for the developed condition. The proposal is a Timber Thinning with ground disturbance to be kept at a minimum. The underlying soils are considered to have very little potential for migration. The filter fabric fence will be installed to protect the wetland and buffer. The flat bottom ditch will be -installed to act as a sediment trap, treatment facility and infiltration pond. #8 Storm Drain Inlet Protection All storm drain inlets made operable during construction shalt be protected se that stormwater runoff shall not enter the conveyance system without first being filtered or otherwise treated to remove sediment. NA No Storm Drains on site. #9 Underground Utility Construction The construction of underground utilities lines shaft be subject to certain criteria. NA No Utilities on site. #10 Construction Access Routes Wherever construction vehicle access routes intersect paved roads, provisions must be made to minimize the transport of sediment (mud) onto the paved road. Construction vehicle access shall be, whenever possible, limited to one route. Stabilized Construction Entrance Detail is shown on the Civil Drawings. #11 Removal of Temporary BMPs All temporary erosion and sediment control BMPs will be removed when final site stabilization is achieved. Except for the filter fabric fence, all other BMP'sare considered permanent erosion and sediment control measures. #12 Dewatering Construction Sites Dewatering devices shall discharge into a sediment trap or sediment pond. NA Groundwater or standing water is not anticipated to become a problem. Lowering the ground water table to facilitate this project will not be an issue. #13 Control -of Pollutants -Other Than- Sediment on Construction- Sites - All pollutants other than sediment that occur on -site during construction shall be handled and disposed of in a manner that does not cause contamination of stormwater: #14 Maintenance All temporary and permanent erosion and sediment control BMPs shall be maintained and repaired as needed to assure continued performance of intended function_ #t5 Financial Liability Mason County has not indicated any requirement for bonding. SETTING UP THE STORMSHED SOFTWARE The software is set up to detain and retain stormwater in a single level bottomed pond of any size and any side slope. The proposal is to hold water back in a flat bottomedditch with a sloping bottom. Several rock check dams will be used to hold the water back. It is anticipated that the water at the check dam will be 1.5' deep and the water depth will diminish to zero up grade from the check dam. The water depth at the check dam for a 100 year storm event is 1.5 feet for both the east and west basins_ A B LENGTH VARIES DEPENDING ON DITCH SLOPE WATER LEVEL 1,5' DITCH SLOPE Rock Check Dam 4,5' Rock\ Check Dam 830' LENGTH VARIES DEPENDING ON DITCH SLOPE 4.5' 4,5' tNN 1.5' I i 8.0' CROSS SECTIONAL AREA OF PONDED WATER AT POINT A' AREA A = (8'+4.5) * 1.5'= 18.75 sf AREA A' + AREA 'B' 8,0' 8.0' CROSS SECTIONAL AREA OF PONDED WATER AT POINT B' AREA B=8'* 0'=0sf 2 = 9.375 sf X LENGTH BETWEEN DAMS SURFACE AREA OF PONDED WATER BETWEEN POINT 'A' & POINT B' (4.5' + 8' + 4.5) + 8' 2 = VOLUME BETWEEN DAMS IN CF = 12.50' X LENGTH BETWEEN DAMS = SURFACE AREA OF PONDED WATER VOLUME EAST BASIN 5,53 ACRES SECT❑N LENGTH 1 138' 2 118' 3 78' 4 78' 5 78' TOTAL VOLUME EAST BASIN VOLUME 1294 cf 1106 cf 731 cf 731 cf 731 cF 4593 cf SURFACE AREA EAST BASIN 5,53 ACRES SECTI❑N LENGTH 1 138' 2 118' 3 78' 4 78' 5 78' SURFACE AREA 1725 sr 1475 sf 975 sf 975 sf 975 sf TOTAL SURFACE AREA 6125 sF EAST BASIN WEST BASIN 4,43 ACRES SECT❑N LENGTH 1 190' 2 100' 3 60' 4 60' 5 52' 6 38' TOTAL VOLUME WEST BASIN VOLUME 1781 cf 938 cf 563 cf 563 cf 488 cf 356 cf WEST BASIN 4.43 ACRES SECTI❑N LENGTH 1 190' 2 100' 3 60' 4 60' 5 52' 6 38' SURFACE AREA 2375sf 1250 sf 750 sf 750 sf 650 sf 475 sf 4689cf TOTAL SURFACE AREA 6250sf WEST BASIN MODEL SOFTWARE In the Nodes - Trap section of the software, adjustments were made to the depth of water, and the pond side slopes to get a computer generated pond to have the same volumes and surface areas for a 100 year, 24 hour storm event, as shown in the above calculations. BASIN EAST WEST LENGTH 500 500 WIDTH SIDE SLOPES 8 2,25 VOLUME CF 4599.13 SURFACE AREA SF 6115,43 8 2,41 4665,86 6262,62 DRAINAGE BASIN East 5.53 acres Alderwood gravelly sandy loam (Abj, 5 - 15 percent slope; Hydrologic Soil Group C Flat bottom Ditch with Cheek Dams Remarks CN# Soil Group Acres Timbered 76 C 5.53 Tc (300' g 15%; w/ Coeff 0.40 plus 600' C 15%; w/ Coeff 0.06) 25.49 minutes Thinning 81 C 5.53 Tc (300' 15%; w/ Coeff 0.40 plus 500' 15%; w/ Coeff 0.035 21.30 minutes DESIGN RESULTS Predeveloped2 Undeveloped Acreage = 5.53 Storm Event 6-Month Two-year Ten-year 100-year Pre Flow -cfs 0.38 1.51 2.90 5.06 Post Developed2 before flat bottom ditch and infiltration Developed Acreage = 5.53 Storm Event 6-Month Two-year Ten-year 100-year Post Flow -cfs 0.79 2.13 3.69 6.12 Post Logging after infiltration in flat bottom ditch (floor 500' x 8' with sideslopes 3' horizonal by 1' vertical plus check dams.) Infiltration rate 6.0 in/hr; Broad Weir 8' wide; Weir height 1.15' above ditch floor_ Storm Event 6-Month Two-year Ten-year 100-year Post Flow -cfs 0.00 0.28 2.46 5.05 Volume -cf 486 2860 3801 4606 (4593) OK Depth- at dam -ft 0.71 1.20 1.3 1.50. Infiltration -cfs 0.45 0.69 0.8I 0.89 DRAINAGE BASIN West 4.47 acres Alderwood gravelly sandy loam (Ab), 5 - 15 percent slope; Hydrologic Soil Group C Flat bottom Ditch with Check Dams Remarks CN# Soil Group Acres Timbered 76 C 4.47 Tc (300' @ 15%; w/ Coeff 0.40 plus 350' @ 15%; w/ Coeff 0.06) 23.48 minutes Thinning 81 C 4.47 Tc (300' @ 15%; w/ Coeff 0.40 plus 300' C 15%; wf Coeff 0.035 20.37 minutes DESIGN RESULTS Predeveloped Undeveloped Acreage = 4.47 Storm Event 6-Month Two-year Ten-year 100-year Pre Flow -cfs 0.22 0.88 1.71 3.02 Post Developed before flat bottom ditch and infiltration Developed Acreage = 4.47 Storm Event 6-Month Two-year Ten-year 1001-yrear Post Flow -cfs 0.46 1.30 2.26 3.72 Post Logging after infiltration inflat bottom ditch (floor 500' x 8' with sideslopes 3' horizonal by 1' vertical plus check dams.) Infiltrationrate.&.0 inlhr; Broad Weir 8' wide; Weir height 1.27' above ditch floor. Storm Event 6-Month Two-year Ten-year 100--Year Post Flow -cfs 0.00 0.00 0.79 2.63 Volume -cf 291 2085 3893 4675 (4689) OK Depth at dam -ft 0.66 1.04 1.37 1.50 Infiltration -cfs 0.42 0.76 0.91 0.96 CONSTRUCTION 0 0 W 0 0_ APPROVAL EXPIRES Z C2 CC ENCINEER5 CERTIFICA TE