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HomeMy WebLinkAboutLog190 Stormwater Pollution Prevention Plan (SWPPP) for Marrowstone Island Water Main Extension 1. Purpose. To serve as the SWPPP for the Marrowstone Island Water Main Extension Construction Project. 2. Background. a. As a result of seawater intrusion problems and the lack of potable ground water on Marrowstone Island, Jefferson County, PUD# 1 of Jefferson County was petitioned to purvey water to the Island residents. b. The project involves the installation of approximately 120,000 feet of 8,6,4, and 2 inch C900 PVC water line on Marrowstone Island. The project includes service meters, several fire hydrants, and other various water system accoutrements. c. Water lines will be installed in rights of way and easements on State Route 116, numerous Jefferson County roads, and on private roads. In most cases water lines will be positioned within the ditch lines which are maintained on a regular basis by both State and County road crews. d. The PUD has been working with the State Department of Transportation and County Public Works to position the water lines where they will have the least effect on the roads. In many cases this conflicts with our efforts to have the minimal impact on existing vegetation within the right of way (eg. Trees, shrubs, flowerbeds, driveways, etc.) e. Marrowstone Island is located in the Olympic Rain Shadow and as such receives less than 18 inches a year of precipitation. 3. General Description of project. This project, although quite large in scale is limited in scope. Basically, the PUD will be installing water lines (8 inches or less), generally behind or in the ditch line, in some cases in the shoulders, and where possible on the far side of the ditch line. Positioning of the water lines will be lAW the controlling agencies desires. In general, we try to cooperate to minimize disruption to existing environment. Along SR116, State DOT has allowed us to position our water lines on the back side or in the ditch, as necessary. They have requested that we decrease the depth of the existing ditch line to better match the roadway. This would provide a safer road for both vehicles and pedestrians. In general all crossings of the State and County roads will be encased. See drawings for details. The County PW' s has been working with the PUD to meet their requirements to have the water line as far as possible from the roadway, while acknowledging that the existing terrain restricts our ability to position the water lines. The County has agreed to review on a case by case basis the requirement to bore across all roads. MLA05-00276 LOG ITEM # lCVJ Pag'3 _Lot..L.L 17 March 2006 4. Objectives of this Plan a. To implement Best Management Practices (BMPs) to minimize erosion and sediments from rainfall runoff at construction sites, and to identify, reduce, eliminate or prevent the pollution of stormwater. b. To prevent violations of surface water quality, ground water quality, or sediment management standards. c. To prevent, during the construction phase, adverse water quality impacts including impacts on beneficial uses of the receiving water by controlling peak rates and volumes of stormwater runoff at the permittee's outfalls and downstream of the outfalls. d. To eliminate any possible discharges of unpermitted process wastewater, domestic wastewater, illicit discharges, and non-contract cooling water to stormwater drainage systems and surface waters of the state. 5. General Requirements. The PUD will be the permittee and responsible for the implementation of the SWPPP. The SWPPP will be provided to the contractor as part of the bid documents, this will allow the contractor sufficient time to plan and the implementation the provisions of this SWPPP. The PUD will designate the Notice Of Intent (NOI), a contact person, who will be available 24 hours a day to respond to emergencies, and to inquires or directives from Ecology. This person will be the PUD project inspector. The contact person shall have authority over the SWPPP implementation. While the PUD is ultimately responsible for proper activities under the general permit and for proper implementation of the SWPPP, both the owner and lor operator of the site may be held liable for any permit violations. The contractor will retain the SWPPP on-site or within reasonable access to the site and make it available upon request to Ecology and local governmental agencies with jurisdiction. The public may obtain a copy of the PUD's SWPPP by request from Jefferson County, Ecology or the PUD. The PUD will retain the SWPPP and copies of the Notice of Intent, inspection reports and all other reports required by this permit for, at least three years after the date of the final stabilization of the construction site. The PUD shall make these documents available upon request by Ecology and by the local government agencies with jurisdiction. Reports on incidents, such as discharge of spills and other noncompliance notification, shall be included in the records. MLA05-00276 ~ Page LOG ITEM L96 7- otJ.L 17 March 2006 4. Modifications: a. Jefferson County or DOE may notify the PUD when the SWPPP does not meet one or more of their requirements. Upon notification by Jefferson County or Ecology, the PUD will take appropriate action(s) to come into compliance. b. Jefferson County or DOE may require SWPPP and BMP modifications if compliance with standards is not being achieved. c. The PUD will modify the SWPPP whenever there is a change in design, construction, operation, or maintenance of any BMP which cause(s) the SWPPP to be less effective in controlling the pollutants. d. Whenever a self-inspection reveals that the description of pollutant sources or the BMPs identified in the SWPPP are inadequate due to the actual discharge of or potential to discharge a significant amount of any pollutant, the SWPPP shall be modified as appropriate. The PUD shall provide for implementation of any modifications to the SWPPP in a timely manner., 7. Applicability of Current and Future Editions of the Stormwater Management Manual for the Puget Sound Basin (SWMM): BMPs were selected from the most recent published edition of the SWMM, August 2001, that has been available for at least 120 days prior to the BMP selection, or other equivalent manuals available at the time of the BMP selection or when the selection of additional BMPs is necessary. If new BMPs are required they will be implemented per DOE and Jefferson County directives. 8. EROSION AND SEDIMENT CONTROL PLAN: a. Stabilization Practices: MLA05-00276 1) Stabilization practices will include: Attempting to place the new water line in areas that will result in the least amount of disturbance to the natural fauna (in the ditch or on the shoulder of the roads), by using mulch, permanent seeding, and geo-textiles; by advocating the retention of existing vegetative buffer strip to DOT and Jefferson County; and by attempting to protect of existing trees, preservation of mature vegetation. A record of the dates when major grading activities occur, when construction activities temporarily or permanently cease on a portion of the site, and when stabilization measures are initiated. Stabilization measures shall be initiated as soon as practicable in portions of the site where construction activities have temporarily or permanently ceased. The following conditions will require application of BMPs: LOG ITEM (S 0 ~ otLL 2) 3) 4) # Page, 17 March 2006 MLA05-00276 i) All exposed and unworked soils shall be stabilized by suitable and timely application of BMPs. ii) Existing vegetation should be preserved where attainable. In the field, mark areas which are not to be disturbed, including setbacks, sensitive/critical areas and their buffers, trees and drainage courses shall be marked or flagged on site before construction activities and initiated. These areas should not be harmed when measures under the SWPPP and/or construction activities are undertaken. iii) Cut and fill slopes shall be designed and constructed in a manner that will minimize erosion. Slopes shall be stabilized in accordance with requirement a. above. iv) Stabilization adequate to prevent erosion of outlets and adjacent stream banks shall be provided at the outlets of all conveyance systems. v) All storm drain inlets made operable during construction shall be properly maintained. vi) Wherever construction vehicle access routes intersect paved roads, provisions must be made to minimize the transport of sediment onto the paved road. If sediment is transported onto a road surface, the roads adjacent to the construction site shall be cleaned on a regular basis. Street washing shall only be allowed after other methods to prevent the transport or to remove the sediments are unsuccessful. b. Structural Practices: There will be a very minimal requirements for any structural BMP's. However, the contractor should implement structural BMPs to divert flows from exposed soils, store flows, or otherwise limit runoff and discharge of pollutants from exposed areas of the site to the degree attainable. Such practices include slit fences, earth dikes, drainage swales, sediment traps, check dams, subsurface drains, pipe slope drains, level spreaders, storm drain inlet protection, rock outlet protection, reinforced soil retaining systems, gabions, and sediment basins. Structural practices should be placed on upland soils to the degree attainable. The installation of these devices may be subject to Section 404 of the Federal Clean Water Act. The following requirements will be satisfied: i) Prior to leaving the site, storm water runoff shall pass through a sediment pond or sediment trap, or other appropriate BMPs. ii) Properties adjacent to the project site shall be protected from sediment deposition. Sediment ponds and traps, perimeter dikes, sediment barriers, and other BMPs intended to trap sediment on-site shall be constructed as a first step in grading. These BMPs shall be functional before land disturbing activities take place. Earthen structures used for sediment control such as dams, dikes, and diversions shall be stabilized as soon LOGSif~EM # (~D Page~otL iii) 17 March 2006 MLA05-00276 iv) Properties and waterways downstream from the construction site shall be protected from erosion due to increases in volume, velocity, and peak flow of storm water runoff from the project site. v) All temporary erosion and sediment control BMPs shall be removed within 30 days after final site stabilization is achieved or after the temporary BMPs are no longer needed. Trapped sediment shall be removed or stabilized on-site. Disturbed soil areas resulting from removal shall be permanently stabilized. c. Selection of Stabilization and Structural BMPs: The PUD has selected BMPs described in Volume II, August 2001, edition of Ecology's Stormwater Management Manual (SWMM) d. Inspection and Maintenance All BMPs will be inspected, maintained, and repaired as needed to assure continued performance of their intended function. All on-site erosion and sediment control measures will be inspected at least once every seven days and within 24 hours after any storm event of greater than 0.5 inches of rain per 24 hour period. e. Record Keeping Reports summarizing the scope of inspections, the personnel conducting the inspection, the date(s) of the inspection, major observations relating to the implementation of the SWPPP, and actions taken as a result of these inspections shall be prepared and retained as part of the SWPPP. f. Compliance Reporting Requirement: Compliance with the maintenance and schedule requirements of the SWPPP and other schedule requirements of this permit constitutes compliance with the reporting requirements of WAC 173-226-180. g. Plans (drawings): The Erosion and Sediment Control Plan consists of two parts: a narrative and a set of site plans (drawings). The drawings are enclosed. Because of the nature of the project and the scale plans simply identify locations of water lines and examples of BMPs to be used. 2. Control of Pollutants Other That~~miVI Construction Sites: ~g'3_~ot1L 17 March 2006 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. Chapter 11-3 of the SWMM can be referenced for guidance in controlling other potential pollutants. 3. Coordination with Local Requirements: The PUD is coordinating this application through the Jefferson County Permit Center. They will coordinate with all required agencies. 5. Notice of Termination (NOT) After the site has undergone final stabilization, and all storm water discharges from soil disturbing activities have ceased, and all exposed soils have a permanent vegetative cover, or equivalent permanent stabilization measure with prevent erosion, the PUD will submit a Notice of Termination form. A Notice of Termination will end permit coverage and the responsibility of the PUD. The PUD is responsible for submitting the termination notice in order to end permit coverage. Unless the permit is terminated, Ecology will continue to assess a fee for the permit. 6. Plan requirements to achieve the 12 Elements of a SWPPP. Element Number 1: Mark Clearing Areas. Because we will be working within the right of ways there will not be any need to mark areas. The water lines will be installed within the existing ditch lines. Element Number 2: Establish Construction Access. The contractor will be required to follow the following rules for his staging areas: Construction vehicle access and exit shall be limited to one rout if possible Access point shall be stabilized with quarry spall or crushed rock to minimize the tracking of sediment onto the public roads Wheel was or tire bath should be located on-site, if applicable. Public roads shall be cleaned thoroughly at the end of each day. Sediment shall be removed from roads by shoveling or pickup sweeping and shall be transported to a controlled sediment disposal area. Street washing will be allowed only after sediment is removed in this manner. Street wash wastewater shall be controlled by pumping back on-site, or otherwise be prevented from discharging into systems tributary to state surface waters. Element Number 3: Control Flow Rates MLA05-00276 LOG ITEM # ~O Pagt3_ otlL- 17 March 2006 Properties and waterways downstream from development sites shall be protected from erosion due to increases in the volume, velocity, and peak flow rate of the stormwater runoff from the project site, as required by local plan approval authority. Element Number 4: Install Sediment Controls The duff layer, native topsoil, and natural vegetation shall be retained in an undisturbed state to the maximum extent practicable. Prior to leaving a construction site, or prior to discharge to an infiltration facility, storm water runoff from disturbed areas shall pass through a sediment pond or other appropriate sediment removal BMP. Runoff from fully stabilized areas may be discharged without a sediment removal BMP Sediment ponds, vegetated buffer strips, sediment barriers or filters, dikes, and other BMPs intended to trap sediment on-site shall be constructed as needed or directed by the PUD inspector. Element Number 5: Stabilize Soils All exposed and unworked soils shall be stabilized by application of effective BMPs, that protect the soil from the erosion forces of raindrop impact and flowing water, and wind erosion. From October 1 through April 30, no soils shall remain exposed and unworked for more than 2 days. From May 1 to September 30, no soils shall remain exposed and unworked for more than 7 days. This condition applies to all soils, whether at final grade or not. These time limits may be adjusted by the local permitting authority if it can be shown that the average time between storm events justifies a different standard. Applicable practices include, but are not limited to, temporary and permanent seeding, sodding, mulching, plastic covering, soil application of polyacrylamide (PAM), early application of gravel base on areas to be paved, and dust control. Soil stabilization measures selected should be appropriate for the time of year, site conditions, estimated duration of use, and potential water quality impacts that stabilization agents may have on downstream waters or ground water. Soil stockpiles must be stabilized and protected with sediment trapping measures. MLA05-00276 Work on linear construction sites and activities, including right-of-way and easement clearing, roadway develoJl~n.t...nin.elines, and trenching for LUl:i IIl::M 17 March 2006 # l'1o Pag'3.-Lot-W- utilities, shall not exceed the capability of the individual contactor for his portion of the project to install the bedding materials, roadbeds, structures, pipelines, and/or utilities, and to re-stabilize the disturbed soils, meeting the timing conditions listed above. Element Number 6: Protect Slopes Cut and fill slopes shall be designed and constructed in a manner that will . .. . mmnllize eroSIOn. Consider soil type and its potential for erosion. Reduce the slope runoff waters from off-site with interceptors at top of slope. Off-site stormwater should be handled separately from storm water generated on the site. Diversion of off-site storm water around the site may be a viable option. Diverted flows shall be redirected to the natural drainage location at or before the property boundary. Contain down slope collected flows in pipes, slope drains, or protected channels. Provide drainage to remove ground water intersecting the slope surface of exposed soil areas. Excavated material shall be placed on the uphill side of trenches, consistent with safety and space considerations. Check dams shall be placed at regular intervals within trenches that are cut down a slope. Stabilize soils on slopes, as specified in Element #5. Element Number 7: Protect Drain Inlets All storm drain inlets made operable during construction shall be protected so that stormwater runoff shall not enter the conveyance system without first being filtered or treated to remove sediment. All approach roads shall be kept clean, and all sediment and street wash water shall not be allowed to enter storm drains without prior and adequate treatment is provided before the storm drain discharges to waters of the State. Element Number 8: Stabilize Channels and Outlets MLA05-00276 All temporary on-site conveyance channels shall be designed, constructed, and stabilized to prevent erosion from the expected velocity of flow from a 2 year, 24-hour frequency storm for the expected development. LOG ITEM # BO Pag'3 ~B-ot4-. 17 March 2006 Stabilization, including armoring material, adequate to prevent erosion of outlets, adjacent stream banks, slopes and downstream reaches shall be provided at the outlets of all conveyance systems. Element Number 9: Control Pollutants All pollutants, including waste materials and demolition debris, that occur on- site during construction shall be handled and disposed of in a manner that does not cause contamination of storm water. Cover, containment, and protection from vandalism shall be provided for all chemicals, liquid products, petroleum products, and non-inert wastes present on the site Maintenance and repair of heavy equipment and vehicles involving oil changes, hydraulic system drain down, solvent and de-greasing cleaning operations, fuel tank drain down and removal, and other activities which may result in discharge or spillage of pollutants to the ground or into the stormwater runoff must be conducted using spill prevention measures, such as drip pans. Contaminated surfaces shall be cleaned immediately following any discharge or spill incident. Emergency repairs may be preformed on-site using temporary plastic beneath and, if raining, over the vehicle. Wheel wash or tire bath wastewater, shall be discharged to a separate on-site treatment system or to the sanitary sewer. Application of agricultural chemicals, including fertilizers and pesticides, shall be conducted in a manner and at application rates that will not result in loss of chemical to stormwater runoff. Manufacturers' recommendations shall be followed for application rates and procedures. Management of pH-modifying sources shall prevent contamination of runoff and stormwater collected on the site. These sources include, but are not limited to, bulk cement, cement kiln dust, fly ash, new concrete washing and curing waters, waste streams generated from concrete grinding and sawing, exposed aggregate processes, and concrete pumping and mixer washout waters. Element Number 10: Control De-Watering All foundation, vault, and trench de-watering water, which have similar characteristics to storm water runoff at the site, shall be discharged into a controlled conveyance system, prior to discharge to a sediment trap or sediment pond. Channels must be stabilized, as specified in Element #8. MLA05-00276 Clean, non-turbid de-watering water, such as well-point ground water, can be discharged to systems tributary to state surface waters, as specified in Element #8, provided the de-watering flow does not cause erosion or flooding of the LOG ITEM ".aD 17 March 2006 :ag'3~~ot.u- receiving waters. These clean waters should not be routed through sediment ponds with storm water. Highly turbid or otherwise contaminated de-watering water, such as from construction equipment operation, clamshell digging, concrete pour, or work inside a cofferdam, shall be handled separately from storm water at the site. Other disposal options, depending on site constraints, may include: 1) infiltration, 2) transport off-site in vehicle, such as a vacuum flush truck, for legal disposal in a manner that does not pollute state waters, 3) on-site treatment using chemical treatment or other suitable treatment technologies, or 4) sanitary sewer discharge with local sewer district approval if there is no other option. Element Number 11: Maintain BMPs All temporary and permanent erosion and sediment control BMPs shall be maintained and repaired as needed to assure continued performance of their intended function. All maintenance and repair shall be conducted in accordance with BMPs. Sediment control BMPs shall be inspected weekly, or after a runoff-producing storm event during the dry season, and daily during the wet season. All temporary erosion and sediment control BMPs shall be removed within 30 days after the final site stabilization is achieved or after the temporary BMPs are no longer needed. Trapped sediment shall be removed or stabilized on site. Disturbed soil areas resulting from removal of BMPs or vegetation shall be permanent! y stabilized. Element Number 12: Manage the Project Phasing of Construction - Developmental projects shall be phased where feasible in order to prevent, to the maximum extent practicable, the transport of sediment from the development site during construction. Re-vegetation of exposed areas and maintenance of that vegetation shall be integral part of the clearing activities for any phase. Seasonal Work Limitations- From October 1 through April 30, clearing, grading, and other soil disturbing activities shall only be permitted if shown to the satisfaction of the local permitting authority that silt-laden runoff will be prevented from leaving the construction site through a combination of the following: MLA05-00276 1. Site conditions including existing vegetative coverage, slope, soil type and proximity to receiving water; and 2. Limitations on activities and the extent of disturbed areas; and 3. Proposed erosion and sediment control measures. LOG ITEM # L5.D Pag'3_ULot-U-. 17 March 2006 MLA05-00276 Based on the information provided, and/or local weather conditions, the local permitting authority may expand or restrict the seasonal limitation on site disturbance. If, during the course of the seasonal limitation period, silt-laden runoff leaving the construction site causes a violation of the surface water quality standard or if clearing and grading limits or erosion and sediment control measures shown in the approval plan are not maintained, the local permitting authority shall take enforcement action, including, but not limited to a notice of violation, administrative order, penalty or stop-work order. The following activities are exempt from the seasonal clearing and grading limitations: 1. Routine maintenance and necessary repair of erosion and sediment control BMPs; 2. Routine maintenance of public facilities or existing utility structures that do not expose the soil or result in the removal of the vegetative cover to soil; and 3. Activities where there is one hundred percent infiltration of surface water runoff within the site in approved and installed erosion and sediment control facilities. Inspection and Monitoring - All BMPs shall be inspected, maintained, and repaired as needed to assure continued performance of their intended function. Maintenance of the Construction SWPPP - The Construction SWPPP shall be retained on-site or within reasonable access to the site. The Construction SWPPP shall be modified whenever there is a significant change in the design, construction, operation, or maintenance of any BMP. LOG ITEM # (~[) Pag~_lLot-U- 17 March 2006