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HomeMy WebLinkAboutSEP2012-00031 Repair Storm Damage - SEP Determinations - 5/31/2012 MASON COUNTY DEPARTMENT OF COMMUNITY DEVELOPMENT Planning Division P O Box 279, Shelton, WA 98584 i (360)427-9670 MITIGATED DETERMINATION OF NONSIGNIFICANCE (WAC 197-11-350) SEP2012-00031 Description of Proposal: Repair storm damage to hydroelectric facility on Lilliwaup Creek. The repairs consist of the following: 1. The construction of a mechanically stabilized earth wall and the resloping of the slide scar in the landslide area. 2. The construction of a new pipe to replace the existing failed concrete box culvert 3. The repair of the existing intake box and weir structures. 4. The removal of accumulated sediments within the intake box (80 cubic yards). The dam is upstream of several fish impassable waterfalls. A Habitat Management Plan, Grading Permit, Stormwater Plan, and Geotechnical Report have been submitted for this proposal. Please ignore any reference to the rerouting of Winter Creek - that portion of the project has been cancelled. Proponent: LILLIWAUP GENERATING COMPANY Site Address (If Assigned): 601 N LILLIWAUP ST LILLIWAUP Directions to Site: US HIGHWAY 101 NORTH TO LILLIWAUP, L ON LILLIWAUP ST TO SITE ADDRESS AT THE END 501 N, THEN WALK IN Parcel Number: 323192300000 Legal Description: LOT 2 Lead Agency: Mason County The Lead Agency for this proposal has determined that it does not have a probable significant adverse impact on the environment. An Environmental Impact Statement (EIS) is not required under RCW 43.21 C.030(2)(c). This decision was made after review of a completed Environmental Checklist and other information on file with the Lead Agency. This information is available to the public upon request. MITIGATED MEASURES ARE ATTACHED. Please contact Rebecca Hersha at ext. 287 with any questions. This DNS is issued under WAC 197-11-340(2). The Lead Agency will not act on this proposal for 14 days from the date shown below, when the determination is final. Comments must be submitted to Dept. of Community Development, P.O. Box 279, Shelton WA 98584 by 6/15/2012. Appeal of this determination must be filed within a 14-day period followi g this final determination date, per Mason County Code Chapter 15.11 Appeals. SEP2 12- 0031 Page 1 of,;? MASON COUNTY DEPARTMENT OF COMMUNITY DEVELOPMENT Planning Division P O Box 279, Shelton, WA 98584 1 (360)427-9670 MITIGATED DETERMINATION OF NONSIGNIFICANCE (WAC 197-11-350) SEP2012-00031 CONDITIONS OF THIS DETERMINATION 1) STORMWATER PLAN The approval of this project is subject to the recommendations and specifications outlined in the Stormwater Report prepared by Jacobs Associates, dated April 2012, and compliance with Ecology's 2005 Stormwater Manual. The report shall remain attached to the a oved nd modification permit. All recommendations shall be considered to be req ditions of approval �la%y A fl ro r J Po X /�► P��f�w► AJ/V L° GEOTECHNICAL REPORT 03 J✓ /¢ The approval of this project is subject to the recommendations and specifications outlined in the Geotechnical Report prepared by Jacobs Associates, dated April 2012. The report jdd rema' a ed to the approved grading plans. All recommendations shall be d conditio s of approval. Activity not within the scope of the report will require an ended geotechnical report and Planning Department approval. STORMWATER & GEOTECHNICAL SITE INSPECTION Compliance with an approved Storm Water Plan and Geotechnical Report shall be subject to an on site inspection, or inspections, by the engineer of record or an authorized representative. Said inspection(s) shall be performed in accordance with the approved plan, and prior to any modification that would make a determination of compliance impossible. An inspection report shall be submitted to verify all prevention and mitigation recommendations have been completed in accordance with the approved reports. The inspection report shall be signed and stamped by the stormwater/geotechnical engineer and submitted to- he Mason County Department of Community Development prior to final per approval. opies of the inspection report shall be made available at time of ins X HABITAT MANAGEMENT PLAN The approv roject to subject to the recommendations and specification outlined in the i at Ma ment Plan prepared by Kim Schaumburg (BioResources), dated May 2012. � SEP2012-00031 Page Z..+ 3 MASON COUNTY DEPARTMENT OF COMMUNITY DEVELOPMENT Planning Division P O Box 279, Shelton, WA 98584 041 (360)427-9670 MITIGATED DETERMINATION OF NONSIGNIFICANCE (WAC 197-11-350) SEP2012-00031 HABITAT MANAGEMENT PLAN INSPECTION An inspection letter/report shall be submitted to verify compliance with the approved Habitat Management Plan. The report shall be signed and stamped by the author of the plan or ' or fie designee and submitted to the Mason County Department of Community D opment pr�r to final permit approval. Copies of the inspection report shall be made a ime of inspection. WATER QUALITY Water u to be degraded to the detriment of the aquatic environment as a result of project. De is or deleterious material resulting from construction shall be removed from e 'ect site and shall not be allowed to enter waters of the State. HYDRAULIC PR JECT APPROVAL raulic Proje Approval (HPA) shall be obtained from the Washington Department of life prior to beginning any site preparation and construction work. ARCHAEOLOGICAL RESOURCES Archaeological or historical resources, such as ruins, sites, buildings, artifacts, fossils, or other objects of antiquity that may have significance from an historical or scientific standpoint, which be encountered by the developer/contractor, shall not be further disturbe a deve er/contractor encounters any such artifacts, he/she shall imm diatel st ork and notify Mason County and the Washington State Department of Archaeo reservation. Failure to do so may result in civil penalties. SEP2012-00031 Page -5 _4 3 MASON COUNTY ENVIRONMENTAL CHECKLIST 1 C� �Xf �0 z9m 3,2 3 MASON CO. ENVIRONMENTAL CHECKLIST -�y-a0000 -��f cuo 30 A. BAC KG RO U N D 1. Name of proposed project, if applicable: Lilliwaup Falls Power Project— Landslide and Intake Area Repairs 2. Name of applicant: Lilliwaup Falls Generating Company. 3. Address and phone number of applicant and contact person: Craig Norsen, (206) 628-3150, (206) 808-7854, craign@senecagroup.com 4. Date checklist prepared: 4-19-12. 5. Agency requesting checklist: Mason County 6. Proposed timing or schedule (including phasing, if applicable): Work to be completed upon receiving all required permits, as per the HPA provisions. 7. Do you have any plans for future expansion, or further activity related to or connected with this proposal: if yes, explain. In the future, Winter Creek may require bank stabilization and channel realignment. 8. List any environmental information you know about that has been prepared, or will be prepared, directly related to this proposal. An HMP has been submitted to Mason County. 9. Do you know whether applications are pending for governmental approvals of other proposals directly affecting the property covered by your proposal? If yes, explain. No. 10. List any government approvals or permits that will be needed for your proposal, if known. A Shoreline exemption permit, an MEP & HMP, plus an HPA from the WDFW. MASON COUNTY ENVIRONMENTAL CHECKLIST 2 , 11. Give a brief, complete description of your proposal, including the proposed uses and the size of the project and site. There are several questions later in this checklist that ask you to describe certain aspects of your proposal. You do not need to repeat those answers on this page. (Lead agencies may modify this form to include additional specific information on project description.) Stabilizing of the slide area will involve the construction of a 60 feet (height) by 145 feet (length) by 40 feet (depth) mechanically stabilized earth (MSE) wall, using a system of welded wire mats and facing to build an embankment across the slide area. The MSE wall will have a face slope of % horizontal to 1 vertical. The existing steep slopes of the upper slide scar will be re-graded to a stable 2H to 1V slope, and the resulting material will be used to fill the embankment area. The size of the area to be re-sloped is approximately 109,000 square feet (2.5 acres). Approximately 43,000 square feet (1 acre) of existing native vegetation will be lost in the re- sloping. An existing access road will be extended across the completed upper slope area. A new 48-inch diameter high density polyethylene pipe (HDPE) will extend approximately 500 feet from an existing gate house to an existing screen house. This pipe shall be buried. The MSE wall face and all other disturbed ground areas will be hydroseeded following construction as per the Washington State Department of Ecology's BMP for temporary and permanent seeding. After the hydroseeded grasses are established the area shall be replanted with native trees. Any disturbed buffer area of Lilliwaup Creek in the vicinity of the MSE wall shall be replanted with native trees and shrubs. In the winter of 2007/2008, high flows in Lilliwaup Creek and Winter Creek damaged the intake area where water is directed into the hydroelectric facility. The intake area is located on the north side of Lilliwaup Creek, above the falls. Winter Creek, an ephemeral (non-perennial) Type F stream, discharges into Lilliwaup Creek immediately adjacent the intake area. Damage included the loss of weir boards that impounded water, loss of a leaf cleaner conveyor, and the destruction of electric components, lighting, railings, and metalwork. Since the downstream concrete flume portions of the system were destroyed in the winter of 2005/2006, the annual sediment flushing of the intake box and adjacent tunnel has not occurred. Consequently, stream sediments (consisting primarily of alluvial gravels and cobble) have accumulated within and around the concrete intake box to a depth of approximately 5 feet above normal operating levels. Proposed repairs to the intake area include the repair of the concrete intake box and weir structures, and the removal of accumulated sediments (approx. 80 cubic yards). Turbidity curtain shall be used, along with additional BMPs, to alleviate downstream turbidity. MASON COUNTY ENVIRONMENTAL CHECKLIST 3 The nearest waterbodies are Lilliwaup, Winter, and Beardsley Creeks. 12. What is the location of the proposal? Give sufficient information for a person to understand the precise location of your proposed project including a street address, if any, and section, township, and range, if known. If a proposal would occur over a range of area, provide the range or boundaries of the site(s). Provide a legal description, site plan, vicinity map, and topographic map, if reasonably available. While you should submit any plans required by the agency, you are not required to duplicate maps or detailed plans submitted with any permit applications related to this checklist Take SR Hwy. 101 north to Lilliwaup and turn left onto Lilliwaup St. Follow to end and cross over bridge onto property. Section 19, Township 23N, Range 03W. The legal description is: TR3-B of VAC PLAT OF LILLIWAUP. B. ENVIRONMENTAL ELEMENTS: 1. EARTH: a. General description of the site (circle one): Flat, rolling, hilly, steep slopes, mountainous, other. b. What is the steepest slope on the site (approx. percent slope)? Approx. 100% and greater. C. What general types of soils are found on the site (for example, clay, sand, gravel, peat, muck)? If you know classification of agricultural soils, specify them and note any prime farmland. Alluvial sediments. d. Are there surface indications of history of unstable soils in the immediate vicinity: If so, describe. Yes. A mass wasting event damaged the existing power facility's flume, necessitating repairs and slope stabilization. e. Describe the purpose, type, and approximate quantities of any filling or grading proposed. Indicate source of fill. 18,600 cubic yards cut and 18,840 filled for this project. Source of the fill is the cut, plus topsoil and mulch for revegetation. MASON COUNTY ENVIRONMENTAL CHECKLIST 4 f. Could erosion occur as a result of clearing, construction, or use: If so, generally describe. The WDOE's Best Management Practices and the WDFW's HPA provisions shall be followed during construction to prevent water pollution. g. About what percentage of the site will be covered with impervious surfaces after project constructions (for example, asphalt or buildings)? The project will not add any new impervious surface to the site. h. Proposed measures to reduce or control erosion, or other impacts to the earth, if any: A Stormwater Report and a Stormwater Pollution Prevention Plan have been prepared as part of this project. 2. AIR: a. What types of emissions to the air would result from the proposal (i.e. duct, automobile, odors, industrial wood smoke) during construction and when the project is completed? If any, generally describe and give approximate quantities, if known. Emissions from any heavy equipment use shall be minor. b. Are there any off-site sources of emissions or odors that may affect your proposal? If so, generally describe. No. C. Proposed measures to reduce or control emissions or other impacts to air, if any: Work to be completed as quickly as possible. 3. WATER: a. Surface: MASON COUNTY ENVIRONMENTAL CHECKLIST 5 1 I r n surface r n r in h immediate vicinity of s there any su ace Ovate body o o the t y the site (including year-round and seasonal streams, saltwater, lakes, ponds, wetlands)? If yes, describe type and provide names. If appropriate, state what stream or river it flows into. Lilliwaup and Winter Creeks. 2 Will the project require an work over, in, or adjacent to within 200 P 1 q Y 1 ( feet) the described waters? If yes, please describe and attach available plans. Yes. 3) Estimate the amount of fill and dredge material that would be placed in or removed from surface water or wetlands and indicate the area of the site that would be affected. Indicate the source of fill material. 80 cubic yards of coarse alluvial sediments (cobble and gravel) 4) Will the proposal require surface water withdrawals or diversions? Give general description, purpose, and approximate quantities if known. No. 5) Does the proposal lie within a 100-year floodplain? If so, note location on the site plan. No. 6) Does the proposal involve any discharges of waste materials to surface waters? If so, describe the type of waste and anticipated volume of discharge. No. b. Ground: 1) Will ground water be withdrawn, or will water be discharged to ground water? Give general description, purpose, and approximate quantities, if known. No. MASON COUNTY ENVIRONMENTAL CHECKLIST 6 2) Describe waste material that will be discharged into the ground from septic tanks or other sources, if any (for example: domestic sewage, industrial, containing the following chemicals...,agricultural, etc.)> Describe the general size of the system, the number of such systems, the number of houses to be served (if applicable), or the number of animals or humans the system(s) are expected to serve. None will be discharged. C. Water runoff (including storm water): 1) Describe the source of runoff (including storm water) and method of collection and disposal, if any (include quantities, if known). Here will this water flow? Will this flow into other waters? If so, describe. See Stormwater Report (April 16h 2012) & Stormwater Pollution Prevention Plan ( April 18t 2012) for Lilliwaup Falls Landslide and Conveyance Pipe Repairs, Jacobs Associates. 2) Could waste materials enter ground or surface waters: if so, generally describe. No. d.Proposed measures to reduce or control surface, ground, and runoff water impacts, if any: The WDOE's Best Management Practices and the WDFW's HPA provisions shall be followed during construction to prevent water pollution. See Stormwater Report (April 16h 2012) & Stormwater Pollution Prevention Plan ( April 18t 2012) for Lilliwaup Falls Landslide and Conveyance Pipe Repairs, Jacobs Associates. 4. PLANTS: a. Check or circle types of vegetation found on the site: _deciduous tree: alder, maple, aspen, other x_evergreen tree: fir, cedar, pine, other x_shrubs x_ grass pasture crop or grain MASON COUNTY ENVIRONMENTAL CHECKLIST 7 wet soil plants: cattail, buttercup, bulrush, skunk cabbage, other _water plants: water lily, eelgrass, milfoil, other other types of vegetation b. What kind and amount of vegetation will be removed or altered? Approximately 34,000 square feet or 0.8 acre of upland forest vegetation shall be removed to insure the stability and integrity of the re- sloped hillside. Approx. 8500 sf (previously or newly disturbed) in the buffer of Lilliwaup Creek shall be replanted, along with 96,000 sf outside of the buffer. C. List threatened or endangered species known to be on or near the site. Unknown. d. Proposed landscaping, use of native plants, or other measures to preserve or enhance vegetation on the site, if any: A planting plan is part of the HMP, Lilliwaup Falls Power Project, April 17, 2012. 5. ANIMALS a. Circle any birds and animals which have been observed on or near the site or are known to be on or near the site: Birds: hawk, heron, eagle, songbirds, other Mammals: deer, bear, elk, beaver, other Fish: bass, salmon, trout, herring, shellfish, other b. List any threatened or endangered species known to be on or near the site. Bull trout (Salvelinus confluentus), marbled murrelet (Brachyramphus marmoratus marmoratus), Puget Sound Chinook salmon (Oncorhynchus tshawytscha), Puget Sound Steelhead (Oncorhynchus mykiss), Hood Canal Summer-Run Chum (Oncorhynchus keta), and the northern spotted owl (Stridex occidentalis). C. Is the site part of a migration route? If so, explain. Yes. Salmonids spawn in Lilliwaup Creek. MASON COUNTY ENVIRONMENTAL CHECKLIST 8 d. Proposed measures to preserve or enhance wildlife, if any: Conservation Measures, including re-vegetating disturbed areas is in the HMP's planting plan. 6. ENERGY AND NATURAL RESOURCES: a. What kinds of energy (electric, natural gas, oil, wood stove, solar) will be used to meet the completed project's energy needs? Describe whether it will be used for heating, manufacturing, etc. None. b. Would your project affect the potential use of solar energy by adjacent properties: If so, generally describe. No. C. What kinds of energy conservation features are included in the plans of this proposal? List other proposed measures to reduce or control energy impacts, if any: None. 7. ENVIRONMENTAL HEALTH: a. Are there any environmental health hazards, including exposure to toxic chemicals, risk of fire and explosion, spill, or hazardous waste, which could occur as a result of this proposal? If so, describe. No. 1) Describe special emergency services that might be required. An ambulance in the event of a construction related accident. 2) Proposed measures to reduce or control environmental health hazards, if any: None. b. Noise: 1) What types of noise exist in the area which may affect your project (for example: traffic, equipment, operation, other)? None. MASON COUNTY ENVIRONMENTAL CHECKLIST 9 2) What types and levels of noise would be created by or associated with the project on a short-term or a long-term basis (for example: traffic, construction, operation, other)? Indicate what hours noise would come from the site. Construction noise will occur during daylight hours. 3) Proposed measures to reduce or control noise impacts, if any" Work to be completed as quickly as possible. 8) LAND AND SHORELINE USE: a. What is the current use of the site and adjacent properties? Residential. b. Has the site been used for agriculture? If so, describe. No. C. Describe any structures on the site. A failed flume, Gate House, Intake Area, Screen House, penstock, Power House, and a single-family residence. d. Will any structures be demolished? If so, what? A failed steel bridge and flume will be removed from the site. e. What is the current zoning classification of the site? R 10. f. What is the current comprehensive plan designation of the site? Unknown. g. If applicable, what is the current Shoreline Master Program designation of the site? Urban Residential. MASON COUNTY ENVIRONMENTAL CHECKLIST 10 h. Has any part of the site been classified as an "Environmentally sensitive" area? If so, specify. Lilliwaup, Winter, and Beardsley Creeks. i. Approximately how many people would reside or work in the completed project? Several. j. Approximately how may people would the completed project displace? None. k. Proposed measures to avoid or reduce displacement impacts, if any: None. i. Proposed measure to ensure the proposal is compatible with existing and projected land uses and plans, if any: The intent of the project is to repair an existing hydroelectric power plant that will supply clean power to Mason County. 9. HOUSING: a. Approximately how many units would be provided, if any? Indicate whether high, middle, or low-income housing. None. b. Approximately how many units, if any would be eliminated? Indicate whether high, middle, or low-income housing. None. C. Proposed measures to reduce or control housing impacts, if any: None. 10. AESTHETICS: a. What is the tallest height of any proposed structure(s), not including antennas; what is the principal exterior building material(s) proposed? MASON COUNTY ENVIRONMENTAL CHECKLIST 11 The proposed armoring shall be approximately 40 feet in height on a sloped grade. b. What views in the immediate vicinity would be altered or obstructed? None. C. Proposed measure to reduce or control aesthetic impacts, if any: None. 11. LIGHT AND GLARE a. What type of light or glare will the proposal produce? What time of day would it mainly occur? None. b. Could light or glare from the finished project be a safety hazard or interfere with views? No. C. What existing off-site sources of light or glare may affect your proposal: None. d. Proposed measures to reduce or control light and glare impacts, if any: None. 12. RECREATION a. What designated and informal recreational opportunities are in the immediate vicinity? Hiking, fishing, etc. b. Would the proposed project displace any existing recreational uses? If so, describe. No. C. Proposed measures to reduce or control impacts on recreation, including recreational opportunities to be provided by the project or applicant, if any: MASON COUNTY ENVIRONMENTAL CHECKLIST 12 None. 13. HISTORIC AND CULTURAL PRESERVATION: a. Are there any places or objects listed on, or proposed for, national, state, or local preservation registers known to be on or next to the site? If so, generally describe. No. b. Generally describe any landmarks or evidence of historic, archaeological, scientific, or cultural importance known to be on or next to the site. None. C. Proposed measures to reduce or control impacts, if any: None. 14. TRANSPORTATION a. Identify public streets and highways serving the site and describe proposed access to the existing street system. Show on site plans, if any. SR Hwy 101. b. Is site currently served by public transit? If not, what is the approximate distance to the existing street system? Show on site plans, if any. Unknown. C. How many parking spaces would the completed project have? How many would the project eliminate? None. d. Will the proposal require any new roads or streets, or improvements to existing roads or streets, not including driveways? If so, generally describe (indicate whether public or private). No. MASON COUNTY ENVIRONMENTAL CHECKLIST 13 e. Will the project use (or occur in the immediate vicinity of) water, rail, or air transportation? If so, generally describe. No. f. How many vehicular trips per day would be generated by the completed project. If known, indicated when peak volumes would occur. None. g. Proposed measures to reduce or control transportation impacts, if any: None. 15. PUBLIC SERVICES a. Would the project result in an increased need for public service (for example: fire protection, police protection, health care, schools, other)? If so, generally describe: No. b. Proposed measures to reduce or control direct impacts on public services, if any: None. 16. UTILITIES a. Circle utilities currently available at the site: electricity, natural gas, water, refuse service, telephone, sanitary sewer, septic system, other.. b. Describe the utilities that are proposed for the project, the utility providing the service, and the general construction activities on the site or in the immediate vicinity which might be needed. None. Signature: The above answers are true and complete to the best of my knowledge. I understand that the lead agency is relying on them to make its decision. MASON COUNTY ENVIRONMENTAL CHECKLIST 14 �ny i 2k,7 Signature: 1G� Date submitted: I �p E 4. Q - x d = q r _ Y STATE OF WASHINGTON DEPARTMENT OF ECOLOGY PO Box 47775 -Olympia, Washington 96504-7775 -(360)407-6300 711 for Washington Relay Service -Persons with a speech disability can call 877-833-6341 June 15, 2012 Ms. Rebecca Hersha e — Your address Mason County ` __ ` is in the Department of Community Development Skokomish- Planning Division _ Dosewallips PO Box 279 watershed Shelton,WA 98584 Dear Ms.Hersha: Thank you for the opportunity to comment on the mitigated determination of nonsignificance for the Lilliwaup Falls Power-Landslide&Intake Area Repair project(SEP2012-00031) located at 601 North Lilliwaup Street in Lilliwaup as proposed by Lilliwaup Generating Company. The Department of Ecology(Ecology)reviewed the environmental checklist and has the following comment(s): WASTE 2 RESOURCES: Mike Drumright(360)407-6397 If greater than 250 cubic yards of inert,demolition,and/or wood waste is used as fill material,a solid waste handling permit is required from the local jurisdictional Health Department(WAC 173-350-990. SEPA REVIEWER: Sonia Mendoza WATER QUALITY CONTACT: Deborah Cornett(360)407-7269 Any discharge of sediment-laden runoff or other pollutants to waters of the state is in violation of Chapter 90.48 RCW, Water Pollution Control,and WAC 173-201A, Water Quality Standards for Surface Waters of the State of Washington, and is subject to enforcement action. Erosion control measures must be in place prior to any clearing, grading,or construction. These control measures must be effective to prevent stormwater runoff from carrying soil and other pollutants into surface water or storm drains that lead to waters of the state. Sand, silt, clay particles,and soil will damage aquatic habitat and are considered to be pollutants. Proper disposal of construction debris must be on land in such a manner that debris cannot enter water of the state(e.g., Lilliwaup and Winter Creek)and stormdrains draining to waters of the state or cause water quality degradation of state waters. Clearing limits and/or any easements or required buffers should be identified and marked in the field,prior to the start of any clearing, grading,or construction. Some suggested methods are staking and flagging or high visibility fencing. June 15,2012 Page 2 A permanent vegetative cover should be established on denuded areas at final grade if they are not otherwise permanently stabilized. Properties adjacent to the site of a land disturbance should be protected from sediment deposition through the use of buffers or other perimeter controls, such as filter fence or sediment basins. Cut and/or fill slopes should be designed to minimize erosion. Methods such as slope roughening,terraces, or pipe slope drains may be used. Ecology's comments are based upon information provided by the lead agency. As such,they may not constitute an exhaustive list of the various authorizations that must be obtained or legal requirements that must be fulfilled in order to carry out the proposed action. If you have any questions or would like to respond to these comments,please contact the appropriate reviewing staff listed above. Department of Ecology Southwest Regional Office (SM:12-2627) cc: Mike Drumright, W2R Deborah Cornett, WQ Lilliwaup Generating Company(Proponent) Craig Norsen, Seneca Group(Contact)