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HomeMy WebLinkAboutSEPA Environmental Checklist - SEP Determinations - 4/12/2012 3628 South 35`h Street Tacoma,Washington 98409-3192 TACOMA POWER TACOMA PUBLIC UTILITIES TACOMA PUBLIC UTILITIES July 14, 2012 ���'' JUL 20 20 Barbara Adkins 426 W.CEDAR S_T_. Mason County PO Box 279 Shelton, WA 98584 Subject: State Environmental Policy Act (SEPA) — Environmental Checklist City of Tacoma Determination of Non-Significance Potlatch Transmission Lines - North Bay Crossing Rebuild Project CITY OF TACOMA FILE #SEP2012 - 40000183278 Tacoma Power is proposing to replace two existing transmission line circuits crossing North Bay Case Inlet in Mason County, Washington. A Substantial Development/Conditional Use PermitNariance application has been submitted to Mason County for this project; file SHR2012-00009-Tacoma Public Utilities. Pursuant to the Washington State Environmental Policy Act, Tacoma Power is sending you the enclosed project SEPA for your review. If you have any comments, information or other pertinent information, please submit them to me by 5 p.m. August 2, 2012. If you have any questions or know of any other agencies or groups who should receive a copy of this document, please call me at (253) 502-8122. Sincerely, 4W A4&�4 Patrick Leach, P.E., S.E. Project Manager Enclosures cc: Mailing List Enclosed 3628 South 35"'Street Tacoma,Washington 98409-3192 TACOMA POWER T TACOKA PVNLIC VTILITI91 ACOMA PUBLIC UTILITIES Determination of Non-significance (DNS) SEPA File Number: SEP2012-40000183278 Description of Proposal: Tacoma Power (TPWR) is proposing to replace its two existing 115kV transmission line circuits crossing the North Bay of Case Inlet, Mason County, Washington. The proposed Potlatch Transmission Lines North Bay Crossing Project would replace the existing Potlatch #1 and #2 lines, and structures crossing North Bay between the communities of Allyn and Victor. The Project would be approximately one mile in length. The portion of the project that would cross the North Bay would be approximately 0.6 miles. Eight of the existing lattice towers and foundations, constructed in 1925, will be replaced, The four in-water structures and foundations will be replaced with one 170 foot pole structure atop a new foundation mid-bay within the existing alignment. Two sets of structures and foundations on either side of the bay will be replaced with new pole structures and foundations approximately 300 feet further from the shoreline. Proponent: City of Tacoma, Department of Public Utilities, Light Division, dba Tacoma Power Location of proposal, including street address, if any: Potlatch 115 kV Transmission Line in Mason County, Crossing North Bay Case Inlet and North Bay Rd. and State Route 302 near the communities of Allyn and Victor, within the southwest ''/. Section 16, Township 22 N, Range 1 W: Latitude 47-23-24 N / Longitude 122-49-09 W Lead Agency: City of Tacoma City Contact: Pat Leach, P.E., S.E., Project Manager 3628 South 351h Street Tacoma, WA 98409-3192 Phone: 253-502-8122 E-Mail: pleach@cityoftacoma.org 3628 South 35° Street T4� Tacoma,Washington 98409-3192 TACOMA POWER TACOMA PUBLIC UTILITIES TACOMA /YOLK VTILIT116 Determination: 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 a review of a completed environmental checklist and other information on file with the lead agency. This information is available to the public on request. The issuance of this SEPA Determination does not constitute final project approval. The proponent must comply with applicable requirements of the City of Tacoma and other agencies with jurisdiction prior to receiving construction permits. This DNS is issued under WAC 197-11-340(2); the lead agency will not act on this proposal for 14 days from the issue date below. Comments must be submitted by August 2, 2012. Responsible Official: David Ward, P.E., Transmission and Distribution Section Manager 3628 South 351h Street Tacoma, WA 98409-3192 Phone: (253) 502-8286 Issue Date: July 19, 2012 You may appeal this Determination of Non-significance: You may appeal this determination to the City of Tacoma Hearing Examiner by filing a written Notice of Appeal together with a filing fee as set forth in TMC 13.12.680, no later than 14 days after the issuance of this determination, or August 2, 2012. Signature: S.A CA , V\") WAC 197-11-960 Environmental checklist. ENVIRONMENTAL CHECKLIST Purpose of checklist: The State Environmental Policy Act(SEPA),chapter 43.21C RCW,requires all governmental agencies to consider the environmental impacts of a proposal before malting decisions. An environmental impact statement (EIS) must be prepared for all proposals with probable significant adverse impacts on the quality of the environment. The purpose of this checklist is to provide information to help you and the agency identify impacts from your proposal(and to reduce or avoid impacts from the proposal,if it can be done)and to help the agency decide whether an EIS is required. Instructions for applicants: This environmental checklist asks you to describe some basic information about your proposal. Governmental agencies use this checklist to determine whether the environmental impacts of your proposal are significant, requiring preparation of an EIS. Answer the questions briefly,with the most precise information known,or give the best description you can. You must answer each question accurately and carefully,to the best of your knowledge. In most cases,you should be able to answer the questions from your own observations or project plans without the need to hire experts. If you really do not know the answer, or if a question does not apply to your proposal, write "do not know" or "does not apply." Complete answers to the questions now may avoid unnecessary delays later. Some questions ask about governmental regulations, such as zoning, shoreline, and landmark designations. Answer these questions if you can. If you have problems,the governmental agencies can assist you. The checklist questions apply to all parts of your proposal,even if you plan to do them over a period of time or on different parcels of land. Attach any additional information that will help describe your proposal or its environmental effects. The agency which g cY to you submit this checklist may ask you to explain our answers or provide additional Y Y P Y information reasonably related to determining if there may be significant adverse impact. Use of checklist for nonproject proposals: Complete this checklist for nonproject proposals, even though questions may be answered"does not apply." IN ADDITION,complete the SUPPLEMENTAL SHEET FOR NONPRO]ECT ACTIONS(part D). For nonproject actions, the references in the checklist to the words "project," "applicant," and "property or site" should be read as"proposal,""proposer,"and"affected geographic area,"respectively. A. BACKGROUND 1. Name of proposed project,if applicable: Potlatch Transmission Lines—North Bay Crossing Rebuild Project 2. Name of applicant: Tacoma Public Utilities 3. Address and phone number of applicant and contact person: Attn:Pat Leach,P.E. 3628 South 35th Street Tacoma,WA 98409-3192 Phone:(253)502-8122 Email:pleach@0ci.tacoma.wa.us 4. Date checklist prepared: April 12,2012 1 TO BE COMPLE fED BY APPLICANT EVALUATION FOR AGENCY USE ONLY 5. Agency requesting checklist: City of Tacoma Tacoma Public Utilities 6. Proposed timing or schedule(including phasing,if applicable): The proposed project includes both upland and in-water work. Primary work constraints include the Washington Department of Fish and Wildlife (WDFW) in-water work window, which restricts work below the ordinary high water mark (OHWM) for 65 days from March 14 through June 15. The other work constraint Is that line outages cannot occur for a period of 151 days from October I through April 30.Due to in-water work timing constraints and limited potential for line outages, project construction must be sequenced. Factoring in these variables, the overall project is anticipated to take approximately one year to complete. It is anticipated that construction of the land-based foundations and towers would begin in the summer of 2013,while construction of the marine foundations,structure,and conductors would occur from January 2014 through August 2014.The proposed construction schedule is outlined below. Proposed Construction Schedule Task Start Date End Date Duration Site Development 6/13/13 7/9113 20 days Land Foundations&Anchors 7/10/13 818/13 22 days Erect Line t(northern circuit)Land 8128113 9/5113 7 days Structures Erect Line 2(southern circuit)Land 916/13 9/16/13 7 days Structures Install Temporary Bay Structures 1/3/14 1/10/14 6 days Tag Off Line 1(1 day outage) 1116/14 1/17/14 2 days Tag Off Line 2(1 day outage) 1120/14 1121/14 2 days Marine Foundations 1/21/14 3/14/14 39 days De-Energize Line 2 5127/14 5128114 2 days Move Line 2 from Temporary 5/28/14 5/29/14 2 days Structure to New Foundation Erect Pre-Assembled Bay Tower 6/2114 616/14 5 days Remove Line 2 Conductors 619/14 6/13114 5 days Demolish Line 2 Upland and Marine 6/16/14 6/20/14 5 days Towers(4 Total) String/Sag Line 2 Conductors 6/23114 6/30/14 6 days Energize Line 2 711/14 7/2/14 2 days De-Energize Line 1 Conductors 7RI14 718114 2 days Remove Line 1 Conductors 718114 7114114 5 days Demolish Line 1 Upland and Marine 7/15/14 7122114 6 days Towers(4 Total) String/Sag Line 1 Conductors 7/23114 7/30/14 6 days Energize Line 1 7131114 8/1/14 2 days Demolish Old Marine Foundations 8/4114 8129114 20 days and Temporary Structures 7_ Do you have any plans for future additions,expansion,or further activity related to or connected with this proposal? If yes,explain. 2 TO BE COMPLETED BY APPLICANT EVALUATION FOR AGENCY USE ONLY No. 8. List any environmental information you know about that has been prepared,or will be prepared,directly related to this proposal. • Critical Areas Report • Biological Assessment • Cultural Resources Report • Joint Aquatic Resource Permit Application(JARPA) • Temporary Erosion and Sediment Control Plan • Spill Prevention Control Plan 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. • Nationwide Permit(Section 404)—U.S.Army Corps of Engineers(also includes compliance with Section 7 of the ESA and Section 106 of the NHPA) • Hydraulic Project Approval—Washington State Department of Fish and Wildlife • Right of Entry/Authorization to Use State Owned Aquatic Lands — Washington State Department of Natural Resources • Water Quality Certification(Section 401)—Washington State Department of Ecology • Coastal Zone Management Act Consistency Determination—Washington State Department of Ecology • Shoreline Substantial Development/Conditional Use Permit—Mason County • Grading Permit Mason County • NPDES Permit Washington State Department of Ecology 11. Give 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.) The City of Tacoma, Department of Public Utilities (TPU) is proposing to rebuild a segment of the Potlatch Transmission Line where it crosses North Bay (see Figures 1, 2, 3, and 4). At least one of the four existing 115-foot-tall steel lattice towers in North Bay is leaning,and all four are deteriorating and in need of seismic upgrade. The double circuit, 110kV Potlatch Transmission Line was originally constructed in 1925 to transmit electricity generated at Cushman Dam to the City of Tacoma.Cushman Dam No.1 is a hydroelectric dam on the North Fork of the Skokomish River In Mason County that forms Lake Cushman. It was built from 1924 to 1926. Two 21,600-kilowatt generators provide 127 million kilowatt-hours annually to the Tacoma Power system. The transmission of electricity to Tacoma,over lines crossing North Bay,Henderson Bay,and the Tacoma Narrows,was activated on March 23,1926.A second,smaller dam,Cushman Dam No. 27 was completed in December 1930. The design and location of the new structures are the result of an alternatives selection process that Included reviewing existing information on soils, topography, critical areas, existing system requirements, potential future system requirements,and available technologies. This information was augmented with geotechnical boring data and site visits. Site photographs are contained in Figure 5. The alternatives selection process resulted in the preferred alternative, which is now being advanced through permitting and final design. Design drawings are contained in Figure 6. The project involves installing one new,approximately 170-foot-tall tubular steel tower at mid-bay to carry both circuits on davit arms.The two existing pairs of structures(four towers total)in the bay will be removed and replaced with this new taller, but narrower tower. This will reduce the in-water footprint by approximately 75 percent.A pair of tangent structures on each side of the bay will also be replaced with new structures. In summary,four towers in North Bay would be removed and replaced by a taller,single tower. The two existing upland towers on each side of the bay would also be removed and replaced with new towers 3 TO BE COMPLETED BY APPLICANT EVALUATION FOR AGENCY USE ONLY further up or further away from North Bay. All new upland towers will be constructed farther than 200 feet from the shoreline and,therefore,out of shoreline jurisdiction. The project includes three primary construction tasks,including: 1)construction of new structures,2)string the transmission conductors onto the new towers, and 3) removal of the old structures. Because at least one circuit must remain energized at all times, construction tasks will he phased to replace one circuit at a time. Construction phasing will consist of the following primary sequences: • Site development and construction of upland foundations and structures(both sides) • Construction of aquatic foundation and temporary structures • Removal of first existing circuit and towers • Erection of new mid-bay tower • Installation of new first circuit conductors • Removal of second existing circuit and towers • Installation of new second circuit conductors • Removal of temporary structures and old foundations The general location of the existing and proposed structures, and the stringing sites, is depicted in Figures 3 and 4.The three primary construction tasks are described below. Construction of New Structures Construction of new structures consists of two distinct elements, including upland structures and aquatic structures.The process involved with constructing upland versus aquatic structures is very different and will be described separately below. • Upland Structures The project includes the construction of four new upland structures,two on the east side and two on the west side of North Bay.The structures will be anchored and guyed to resist conductor dead-end loading. Buried anchors will be installed approximately 70 feet upland from the structure foundations.Guy wires will be installed between the top of the tower and the anchors. Equipment staging for the upland structures will occur in the immediate vicinity of each new structure. Construction of the new upland structures includes site preparation, foundation and anchor installation, and tower assembly and erection. Prior to foundation installation, site access improvements and a working pad will be constructed. Development of the construction pad involves clearing existing vegetation and debris, grading the ground, and then laying down an approximately 8-inch-thick layer of quarry spells that will form the construction working pad. Each structure requires an approximately 100- by 100-foot working pad, which is used to maneuver equipment and materials and for general parking; and temporary storage of construction equipment, structure components, and general supplies. The working pads (one on each side of the bay)will be within the existing right-of-way. Each upland structure on the west side will be supported by three concrete drilled shaft foundations approximately 5 to 6 feet in diameter and approximately 20 feet deep.Each upland structure on the east side will be supported by one concrete foundation approximately of the same dimensions. Each shaft will require approximately 20 cubic yards of excavation and a similar amount of concrete fill. After the foundations are installed and cured,a crane will be used to position each approximately 70-to 100-foot- tall steel tower in place. It will take approximately three weeks to develop the site and construct the upland foundations and anchors on each side of the bay.It will take approximately four days to assemble and erect each tower. The overall project area footprint for upland construction is approximately 1.6 acres. • Aquatic Structures Construction of the new structure in North Bay will be performed from a barge. The largest potential size of a barge that could be used for this project is 175 feet by 35 feet by 11 feet; the actual size may be 4 TO BE COMPLETED BY APPLICANT EVALUATION FOR AGENCY USE ONLY smaller. The barge will include a crane;deck space for storage;and assembly of structure components, generators, and miscellaneous project equipment. By design, barges are shallow-draft vessels. Use of a barge would be limited to periods of high tide to avoid grounding the vessel. 'The new tower will be supported by four steel piles filled with concrete. Each pile will be 30 inches in diameter and will extend 20 to 25 feet above the mud line. Each pile will be installed with a D-80 or D- 100 impact hammer.Once the four piles are installed and filled with concrete,an approximately 24- by 24-foot tower pad is attached to the top of the piles. The lower edge or the tower pad will be at an elevation of 18 feet (NAVD88 datum), so it is 4 feet above the mean higher high water elevation. The concrete tower pad will be cast in place. Temporary aquatic structures are also anticipated to hold the existing conductors out of the way during construction of the new bay structures and for purposes of a temporary platform.The poles used to hold the existing conductors out of the way could consist of up to six approximately 24-inch diameter by 90- foot-long wood or steel piles driven approximately 15 feet below the mud line and reinforced with down guys attached to two large concrete blocks set on the bay bottom.The temporary platform would likely be held stationary by four steel piles up to 30 inches in diameter. The maximum number of piles proposed for marine construction is 16. This includes four permanent piles for the new structure, and up to 12 temporary piles. All piles will be installed with an impact hammer. For purposes of planning it is assumed the contractor will be able to install a minimum of one pile per day. It only takes approximately two hours to actually drive the pile, but several hours are required for set-up. String New Transmission Conductor Wire setups will be required on each side of the bay, a few hundred feet upland from the new upland structures. One side will include a wire tensioner and reel stands, while the other side will include a wire puller and reel winder. Each site will require approximately a 100- by 100-foot clearing to set up for both circuits. The existing conductor will be cut and allowed to drop into the bay and then reeled up onto spools for disposal.A pilot wire will then be strung by boat or helicopter between the new towers.The pilot wire will be used to pull in the new conductor.The wires and conductors will be pulled through sheaves installed at each tower.Once the new conductor is strung across the bay,it will be dead-ended to the upland tower on one side, pulled up to meet the required sag and tension,and then dead-ended to the upland tower on the other side. The conductor will then be clipped in (permanently attached) to the mid-bay tower. For each circuit, it will take approximately ten days to establish wire setups, remove the old conductors and sag,and dead-end and clip the new conductors. Removal of Old Structures Removal of the old upland towers will be accomplished by a crane and excavator.The excavator will have a demolition boom installed with a hydraulic shear cutter at the end.The existing tower leg members will be sheared such that the crane can lower the lattice tower sections to the ground.The lattice sections will then be further demolished on the ground or hauled in large sections to a salvage yard. Existing concrete pedestals will be removed to below grade.It will take approximately one week to remove each upland structure. Existing aquatic towers will be disassembled in a similar manner as the upland towers,except the crane and excavator will be mounted on barges.Existing aquatic foundations consist of three wood piles per leg(12 per tower) tied together with concrete caps and a concrete frame. The concrete will be cut and removed in sections;the wood piles will be withdrawn from the bay subsurface using similar equipment required to drive the piles for the new aquatic structure.It will take approximately one week to remove each aquatic tower and two weeks to remove each aquatic foundation. 5 TO BE COMPLETED BY APPLICANT EVALUATION FOR AGENCY USE ONLY 12. 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. The project site is located within Mason County,Washington (Sections 16 and 17,Township 22 north,Range 01 west,W.M.). The project area is an approximately 1-mile-long section of the Potlatch Transmission Line that includes crossing approximately 0.6 miles of North Bay in southern Puget Sound.North Bay is located at the northern tip of Case Inlet. B. ENVIRONMENTALELEMENTS 1. Earth a. General description of the site(circle one): la rolling,hilly, tee slo mountainous, other...... Topography along the one-mile length of the transmission line corridor is variable. b. What is the steepest slope on the site(approximate percent slope)? 15-30% c. What general types of soils are found on the site(for example,clay,sand,gravel,peat,muck)? If you know the classification of agricultural soils,specify them and note any prime farmland. Soils on the west side of the bay where the existing structure is located, and where the proposed structure would be constructed, consist of Alderwood gravelly sandy loam on 5 to 15 percent slopes. Soils on the east side of the bay where the existing structure is located consist of Everett gravelly sandy loam on 15 to 30 percent slopes. The area on the east side of the bay where the new structure is proposed consists of Everett gravely sandy loam on 5 to 15 percent slopes. These soil types are not considered hydric. The Alderwood series is generally considered moderately well drained, while the Everett series is generally considered somewhat excessively drained. d. Are there surface indications or history of unstable soils in the immediate vicinity? If so,describe_ No. e. Describe the purpose,type,and approximate quantities of any filling or grading proposed.Indicate source of fill. The overall upland project area is 1.6 acres, which includes existing access roads, the area of disturbance around the existing towers on both sides of the bay that are to be removed, and the area around the new upland towers.The existing access roads need to be improved to accommodate construction equipment,and construction pads must be built to withstand use by the heavy construction equipment involved in building the new towers. In order to construct these improvements, approximately 13,147 square feet of permanent gravel and 2,575 square feet of temporary gravel will be installed on the east side of North Bay, and 15,585 square feet of gravel and 800 square feet of asphalt on the west side of the bay. Improvements to the access roads will consist of 12 inches of crushed surfacing base course per Washington State Department of Transportation(WSDOT)standard specifications.The construction pads or staging areas at each new tower will consist of the same material used for the access roads. The project also includes developing stabilized construction entrances and exit driveways,which will consist of 12 inches of 4-to 8-inch quarry spalls. In summary, construction activities on the east side of North Bay will result in the cut of 143 cubic yards of material and the fill of 3,747 cubic yards. Construction activities on the west side of North Bay will result in the cut of 2,230 cubic yards and the fill of 279 cubic yards. Specifications are contained in Figure 6. The source of material is unknown at present. 6 TO BE COMPLETED BY APPLICANT EVALUATION FOR AGENCY USE ONLY f. Could erosion occur as a result of clearing,construction,or use? If so,generally describe. Erosion could occur during construction. However, all disturbed areas will be stabilized by erosion control measures, and construction equipment will be situated on stable surfaces built per WSDOT standard specifications as outlined above(e.). g. About what percent of the site will be covered with impervious surfaces after project construction(for example, asphalt or buildings)? On the east side of North Bay,the project will install approximately 13,147 square feet of permanent gravel (this excludes the existing 6,541 square feet of gravel that will be replaced), plus an additional 2,575 square feet of temporary gravel(near the existing towers). On the west side of North Bay, the project will install approximately 15,585 square feet of permanent gravel plus 800 square feet of permanent asphalt. On the west side, the project is converting 3,704 square feet of existing impervious surface to pervious(seeded)surface. In summary,the project would cover approximately 18.3 percent of the project site on the east side of the bay and 18.9 percent of the project site on the west side of the bay with impervious surface. g. Proposed measures to reduce or control erosion,or other impacts to the earth,if any: A Temporary Erosion and Sediment Control (TESC) Plan will be developed and implemented. The Best Management Practices (BMPs) in the plans will be used to control sediments generated from all vegetation removal and ground-disturbing activities. Erosion containment measures will include installation of clearing limits and erosion control fencing, use of a quarry spell pad under the construction area, tire washing requirements prior to equipment leaving the project site, and hydroseeding areas with exposed earth once construction activities have been completed. 2. Air a_ What types of emissions to the air would result from the proposal(i.e.,dust,automobile,odors,industrial wood smoke) during construction and when the project is completed? If any,generally describe and give approximate quantities if known. Emissions will be limited to those generated by gas and diesel powered equipment during construction and maintenance.These emissions will be minor and short-term. b. Are there any off-site sources of emissions or odor that may affect your proposal? If so,generally describe. None known. c. Proposed measures to reduce or control emissions or other impacts to air,if any: None proposed. 3. Water a. Surface: I) Is there any surface water body on or in the immediate vicinity of 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. The project site includes North Bay, which is located at the northern tip of Case Inlet in southern Puget Sound.One palustrine wetland(Wetland A)is present in the immediate vicinity of the upland towers on the east side of North Bay(see Figures 4 and 6). 7 L TO BE COMPLETED BY APPLICANT EVALUATION FOR AGENCY USE ONLY 2) Will the project require any work over,in,or adjacent to(within 200 feet)the described waters? ifyes, please describe and attach available plans. In North Bay,the project includes installing one new structure and removing four existing structures(two sets of towers). The project also includes removing two upland structures on each side of the bay, and constructing two new upland structures further from North Bay (see attached plans). The existing structures on the east side of North Bay are within 200 feet of the ordinary high water mark of the bay. These structures are within a wetland and will be permanently removed. No other structures are located within or proposed to he constructed within shoreline jurisdiction. 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. New Marine Structure The new structure in North Bay will be supported by four 30-inch-diameter steel piles that will be driven into the substrate.This process does not require any fill or dredging.However,sediment from within each of the four piles will be removed so they can be filled with concrete.Approximately 0.55 yards'of sediment will be displaced by each pile for a total of 2.2 yards'.Up to a maximum of 12 temporary piles will also be installed during construction of the new marine structure. These temporary piles will be extracted upon completion of the project. Existine Marine Structures There are currently two sets of structures in North Bay(four separate structures).Each existing steel tower is attached to a concrete platform approximately 20 feet square. Each corner of the platform is supported by a concrete pier cast over a 3-wood pile cluster. Each of the concrete piers has a diameter of approximately 36 inches,which currently displaces approximately 0.79 yards'per pier.Therefore,all four structures displace approximately 12.6 yards'of substrate.The new structures will be supported by four 30- inch-diameter piers (piles) and will displace approximately 2.2 yards'of substrate. Therefore, the project will result in an increase of approximately 10.4 yards'of available substrate compared to existing conditions (82.5 percent increase).This increase in available substrate is achieved by removing more piles associated with the existing structures than will be added by the new structure. The existing concrete piers will be completely removed and each of the associated piles will be fully extracted.The process requires disturbing the substrate around each pier or the area under each structure. The overall footprint of each structure, when considering the entire area under each structure and an additional 5-foot-wide area that factors in clearing an adequate space for equipment access, assumes a 25-by 25-foot footprint,or a total area of 625 square feet per structure.This is the maximum total area per structure that would be temporarily disturbed during demolition. Therefore, the total area of temporary disturbance to the substrate during demolition of the existing structures in North Bay is estimated at approximately 2,500 square feet. Wetland A The existing structures on the east side of North Bay are within a wetland. This wetland is identified as "Wetland A"in the Critical Areas Report.These structures are to be permanently removed from Welland A. No permanent fill or dredging in Wetland A is proposed. However, removal of these structures will require temporary disturbance of the area around the existing structures and construction of a temporary crane pad.The project will temporarily impact 2,555 square feet of wetland,which includes removal of both towers and construction of a temporary crane pad. The overall footprint of the crane pad will be 2,573 square feet, of which 1,188 square feet is within Wetland A, resulting in 44 cubic yards of wetland excavation.The plan is to remove both towers and The concrete pedestals they are bolted on to.Each tower is supported by four concrete pedestals.Each pedestal is approximately 18 inches wide and will be broken off approximately two feet below the existing ground level.For purposes of assessing impacts,it is assumed that the demolition process associated with both structures will result in approximately 2,555 square feet of temporary wetland impact and 1,885 square feet of temporary buffer impact.The wetland area within the 8 TO BE COMPLETED BY APPLICANT EVALUATION FOR AGENCY USE ONLY TPU easement (2,158 square feet) that is disturbed during demolition will be planted with red-osier dogwood (Corms slolonifera), while the buffer area within the TPU easement (765 square feet) will be planted with Nootka rose(Rosa nurkana).Areas outside of the TPU easement but within WSDOT right-of- way and the parcel to the south will be hydroseeded. 4) Will the proposal require surface water withdrawals or diversions? Give general description,purpose,and approximate quantities if known. No surface water withdrawals or diversions are required. 5) Does the proposal lie within a 100-year floodplain? Ifso,note location on the site plan. The project site includes North Bay,which is tidally influenced.No riverine floodplains occur in the project area. 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 discharge of waste material to surface waters is proposed or anticipated. 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 ground water will be withdrawn and no water will be discharged to ground water. 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. Not applicable. c_ Water runoff(including stormwater): 1) Describe the source of runoff(including storm water)and method of collection and disposal,if any(include quantities,if known). Where will this water flow? Will this water flow into other waters? If so,describe. Rainfall directly on the area within the project limits and over-ground flow from areas uphill from the project limits are the sources of potential runoff. Runoff will be collected and detained downhill from the project limits, and released (in accordance with the 2005 Stormwater Management Manual for Western Washington) through dispersion or to existing drainage ditches that eventually convey runoff to state waters. 2) Could waste materials enter ground or surface waters? If so,generally describe. It is possible for waste material to enter surface waters (specifically North Bay). This would generally include sediment from the disturbed areas during demolition/construction.BMPs are proposed to minimize the transport of sediment(waste materials)to surface waters. d. Proposed measures to reduce or control surface,ground,and runoff water impacts,if any: The project includes preparation of TESC and Spill Prevention, Control,and Countermeasure (SPCC) plans. BMPs will be implemented to reduce or control impacts. Tbese BMPs include limiting the disturbed areas to only those areas needed to complete the proposed work, installation of silt fencing and straw wattles, inlet protection,stabilized construction exits,and site monitoring during construction. 9 TO BE COMPLETED BY APPLICANT EVALUATION FOR AGENCY USE ONLY 4. Plants a. Check or circle types of vegetation found on the site; deciduous tree: alder,maple,aspen,other evergreen tree: fir,cedar,pine,other shrubs wwd pasture crop or grain wet soil plants: cattail, uttercu bulrush,skunk cabbage,other —water plants: water lily,eelgrass,milfoil,other other types of vegetation(see 4.b.below) b. What kind and amount of vegetation will be removed or altered? No macrophytes will be removed or altered during the construction of the new structure or the removal of the existing structures in North Bay. Vegetation under the transmission line corridor is regularly maintained, and trees are not allowed to become established.Scotch broom(Cylisus scoparius)is the dominant species on the east side of North Bay.The west side of the bay is more pasture-like under the transmission lines,and is composed of an array of grasses and weeds.Some isolated shrubs are present,but very few. Construction of each structure requires an approximately 100- by 100-foot working pad. All vegetation within this area will he temporarily impacted by construction activities. Vegetation under and immediately adjacent to the structures in Wetland A includes reed canarygrass(Phalaris arundinacea),soft rush(Juncos eJj'usus),Himalayan blackberry(Rubus armeniacus),giant horsetail(Equisetum telmareia), cleavers bedstraw (Calium aparine), creeping buttercup (Ranunculus repens), moss, and other unidentified grasses and weeds. The proposed project would result in temporary impacts to Wetland A and its buffer.These temporary impacts are the result of permanently removing two structures from Wetland A. The area to be disturbed is on historic fill material and is dominated by invasive or weedy species. c. List threatened or endangered species known to be on or near the site. No threatened or endangered plant species are known to be on or near the site. d. Proposed landscaping,use of native plants,or other measures to preserve or enhance vegetation on the site,if any: After construction,disturbed upland areas will be hydroseeded with a grass mixture. Temporary impacts to Wetland A within the TPU easement will be mitigated by replanting the disturbed wetland area with red-osier dogwood,and the disturbed buffer area with Nootka rose.Areas outside the easement within WSDOT right-of-way will be hydroseeded. 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; 1hawk,heron eagle,songbirds,other:os r mammals: deer,bear,elk beaver,other: fish: bass, Ting,shellfis other: 10 TO BE COMPLETED BY APPLICANT EVALUATION FOR AGENCY USE ONLY b. List any threatened or endangered species known to be on or near the site. Case Inlet is known to be utilized by Chinook salmon,steelhead trout,and occasionally orca whales.The waters of North Bay are too shallow for orca whales. A few Chinook salmon can be anticipated to seasonally move through North Bay towards Coulter Creek.These Chinook salmon are likely hatchery strays.Steelhead trout are rumored to occasionally utilize Coulter Creek. c. Is the site part of a migration route? If so,explain. The site is not part of a migration route in the typical sense of a flyway, such as the Pacific flyway. However, marine waterways and their associated shorelines are used by numerous species as migration corridors. d. Proposed measures to preserve or enhance wildlife,if any: The number of in-water structures is being reduced from four to one,while existing shoreline structures are being replaced further from the bay. Impact minimization measures are proposed to reduce noise from marine pile driving (a bubble curtain and pile cushion), and BMPs will be implemented to reduce the potential of erosion,spills,or increased turbidity.Since both marine towers are used for nesting,the nests used by herons on the west bay tower and osprey on the east bay tower will be removed prior to the nesting season when construction is proposed, and measures to discourage nesting will be implemented so they do not re-establish nests on the towers that are to be demolished.Restoration of areas disturbed during construction in Wetland A is also proposed,which will enhance wildlife habitat by adding a native shrub component. 6. Energy and natural resources a. What kinds of energy(electric,natural gas,oil,wood stove,solar)will be used to meet the completed projeot's energy needs? Describe whether it will be used for heating,manufacturing,etc. The project is a maintenance action along an existing electrical transmission line used to transmit electricity from Cushman Dam to the City of Tacoma. 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: Not applicable. 7. Environmental health a. Are there any environmental health hazards,including exposure to toxic chemicals,risk of fire and explosion, spill,or hazardous waste,that could occur as a result of this proposal? If so,describe. The construction process includes the use of various types of equipment that will contain petroleum products such as gas,diesel,oil,and hydraulic fluids.These products are toxic and some can explode or spill and become an environmental health hazard. 1) Describe special emergency services that might be required. Not applicable. 2) Proposed measures to reduce or control environmental health hazards,if any: The containment of toxic chemicals and measures to reduce potential spills from construction-related liquids such as gas,oil,hydraulic or radiator fluids,or other hazardous materials used during demolition or construction of the structures will be outlined in the SPCC. The SPCC will also include requirements to have spill containment kits, agency contact information, and designation of an individual responsible for training and preparation for spill response. 11 TO BE COWLE I ED BY APPLICANT EVALUATION FOR AGENCY USE ONLY b. Noise 1) What types of noise exist in the area which may affect your project(for example:traffic,equipment, operation,other)? Existing noise from SR 302 and SR 3 are generally minor and will not affect the project. 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. Noise levels generated during construction are based on the type of equipment used and methods of construction. Pile driving will be the loudest construction-related activity, which is anticipated to reach 110 dBA.However,noise will typically be below 110 dBA and is anticipated to average 84 dBA.Operational noise is limited the hum or buzz associated with an 110kV electrical transmission line.The proposed action will not change the existing 110kV line to a higher transmission rate,so no change in operation noise level is anticipated. 3) Proposed measures to reduce or control noise impacts,if any: No measures to reduce or control noise impacts are proposed for upland work,but work within the marine environment includes use of a bubble curtain and pile cushion to reduce construction-related noise impacts to fish and wildlife. 8. Land and shoreline use a. What is the current use of the site and adjacent properties? The project area is an existing powerline transmission corridor, while the adjacent properties include undeveloped/forested parcels and single-family residences. A WDFW beach access parking lot is present immediately north of the project area on the east side of North Bay.Within the marine environment commercial shellfish operations exist on the west side of the bay,while recreational shellfish harvest occurs on the east side of the bay. b. Has the site been used for agriculture? If so,describe. No. c. Describe any structures on the site. There are four existing marine towers and four existing upland towers on the site. d. Will any structures be demolished? If so,what? The four existing marine towers and four existing upland towers will be demolished. e. What is the current zoning classification of the site? The west side of North Bay is zoned Urban Growth Area because it crosses the northern edge of Allyn,while the east side is zoned Rural Residential 5 Acres.According to the Allyn Urban Growth Area Zoning Map,the west side of North Bay is zoned Single Family Residential (R-1) between North Bay and E. North Bay Road, and Business Park(BP) to the west of E. North Bay. Within the Allyn Urban Growth Boundary,the existing and proposed towers are both within the area classified as Business Park. f. What is the current comprehensive plan designation of the site? The project area on the west side of North Bay is within the Urban Growth Area associated with Allyn,while the east side is mapped as rural area. 12 TO BE COMPLETED BY APPLICANT EVALUATION FOR AGENCY USE ONLY g. I f applicable,what is the current shoreline master program designation of the site? The current shoreline environmental designation is Urban Residential on both sides of the bay.Marine waters or Mason County lying immediately adjacent to shorelands designated as an Urban Residential environment shall be considered as Urban Residential environment from the line of mean higher high tide(MHHT)to a depth of one fathom (6 feet), as determined by the USCS. According to the Shoreline Management Plan (SMP), the MHHT for Allyn—Case Inlet is 14.13 feet.From one fathom to ten fathoms in depth is considered a Conservancy environment. h. Has any part of the site been classified as an"environmentally sensitive"area? If so,specify. North Bay and Wetland A have both been classified as environmentally sensitive areas. i. Approximately how many people would reside or work in the completed project? None. j. Approximately how many people would the completed project displace? None. k. Proposed measures to avoid or reduce displacement impacts,if any: None. I. Proposed measures to ensure the proposal is compatible with existing and projected land uses and plans,if any: All new structures are within the existing TPU powerline transmission corridor.All new upland structures have been situated to be outside of shoreline jurisdiction and critical areas, while the marine footprint has been reduced by 75 percent compared to existing conditions. 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? The tallest structure will be the marine tower which would be an approximately 170-foot-tall tubular steel tower. b. What views in the immediate vicinity would be altered or obstructed? All towers are within an existing powerline transmission corridor. The proposed tower is 170 feet tall, while existing towers are approximately 120 feet tall. However, there are currently four marine towers, and after construction there will be one marine tower.No views will be obstructed. c. Proposed measures to reduce or control aesthetic impacts,if any: There will be a reduction in the number of marine towers. 13 TO BE COMPLETED BY APPLICANT EVALUATION FOR AGENCY USE ONLY 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 desigmated and informal recreational opportunities are in the immediate vicinity? Recreational activities include fishing in/along North Bay,and harvesting shellfish. b. Would the proposed project displace any existing recreational uses? Ifso,describe. The project won't displace any existing recreational uses along the shoreline, but fishers within the bay would need to navigate around the barge(s) during construction. The project would not permanently displace any recreational uses. c. Proposed measures to reduce or control impacts on recreation,including recreation opportunities to be provided by the project or applicant,if any: 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. Tacoma Power recently submitted to the Washington State Department of Archaeology and Historic Preservation (DAHP)a revised National Register of Historic Places(NRHP)nomination form for the Cushman Hydroelectric Development Historic District(Perrin 2012). Four pairs of the Potlatch Transmission Line North Bay crossing towers,slated for replacement as part of the current project,are recommended to be a contributing resource within that district and therefore historic properties as defined in the NRHP. b. Generally describe any landmarks or evidence of historic,archaeological,scientific,or cultural importance known to be on or next to the site. Project-related activities are in the immediate vicinity of an archaeological site(45MS107),which is defined as a low density scatter of chipped stone artifacts and fire-cracked rocks. As outlined in the draft Cushman Hydroelectric Development Historic District nomination: "The segment of the Potlatch Transmission Line at the crossing of North Bay is approximately one mile long and consists of six pairs of single-circuit steel-lattice towers on concrete foundations/piers:two on the west side of North Bay in the town of Allyn,two in the bay anchored on concrete piers,and two on the east side of the bay west of the Vaughn Tap (where some power is delivered to local distribution systems).'I be tower pairs are spaced evenly about 1,000 feet apart.These structures are original to the Cushman electric power generation and transmission system, retain integrity of design, materials, workmanship, feeling, association, setting, and location, and are a contributing structure to the historic district"(Perrin 2012:7-18). 14 i TO BE COMPLETED BY APPLICANT EVALUATION FOR AGENCY USE ONLY c. Proposed measures to reduce or control impacts,if any: The project team includes an archaeologist and, based on his findings, the project is unlikely to impact any archaeological resources. The project will limit ground-disturbing activities near the recorded site to an area containing previously-disturbed soils.The project archaeologist has recommended developing a Mo nitoring and Unanticipated Discovery Plan for this site,which will be implemented. Under Tacoma Power's Federal Energy Regulatory Commission License No. 460 Article 414 of their License Tacoma Power is constructing fish-passage improvements at Cushman No. 1 Dam. Tacoma Power and DAHP determined that construction will constitute an unavoidable adverse effect on the Cushman No. 1 Power Plant Historic District,a historic roe listed in the NRHP as defined in 36 CFR Pa 80 . property rti' , Part 0 l6(1)(1).Tacoma Power i and DAHP entered into a memorandum of agreement gr (MOA, executed February 28,2012)to mitigate for these effects. Partial mitigation includes completion of Historic American Engineering Record documentation as well as completion of the revised district nomination,currently under review. Mitigation for removal of the existing structures associated with the North Bay will be developed in consultation with the DAHP and implemented by Tacoma Power. 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. Major roadways in the project vicinity include SR 302, SR 3, and E. North Bay Road. SR 302 parallels the eastern shoreline and northern tip of North Bay, while SR 3 and E. North Bay Road are the primary thoroughfares on the west side of North Bay. b. Is site currently served by public transit? If not,what is the approximate distance to the nearest transit stop'? The site is not currently served by public transit.It is unknown where the nearest transit stop is located. c. How many parking spaces would the completed project have? How many would the project eliminate? Not applicable. 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). There are existing roads along or to all upland sites. However, some improvements will be required so that construction equipment can safely access these sites. Roadway improvements are limited to private streets or access roads. e. Will the project use or occur in the immediate vicinity p � { v mlty of)water,rail,or air transportation. If so,generally describe. No. E How many vehicular trips per day would he generated by the completed project?If known,indicate 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 services(for example:fire protection,police protection,health care,schools,other)? If so,generally describe. 15 1 TO BE COMPLETED BY APPLICANT EVALUATION FOR AGENCY USE ONLY 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: Wlectrici ,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. No new utilities are proposed.Tacoma Power will continue to operate and maintain the existing transmission line corridor. C. 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. Signature: .............................................................y.../F ..... .................................................. ............................................ Date Submitted: a/� 16 TO BE COMPLETED BY APPLICANT EVALUATION FOR AGENCY USE ONLY D. SUPPLEMENTAL SHEET FOR NONPROJECT ACTIONS (do not use this sheet for project actions) Because these questions are very general,it may be helpful to read them in conjunction with the list of the elements of the environment. When answering these questions,be aware of the extent the proposal,or the types of activities likely to result from the proposal,would affect the item at a greater intensity or at a faster rate than if the proposal were not implemented. Respond briefly and in general terns. 1. How would the proposal be likely to increase discharge to water;emissions to air;production,storage,or release of toxic or ha72rdous substances;or production of noise? Proposed measures to avoid or reduce such increases are: 2. How would the proposal be likely to affect plants,animals,fish,or marine life? Proposed measures to protect or conserve plants,animals,fish,or marine life are: 3. How would the proposal be likely to deplete energy or natural resources? Proposed measures to protect or conserve energy and natural resources are: 4. How would the proposal be likely to use or affect environmentally sensitive areas or areas designated(or eligible or under study)for governmental protection;such as parks, wilderness,wild and scenic rivers,threatened or endangered species habitat,historic or cultural sites,wetlands,floodplains,or prime farmlands? Proposed measures to protect such resources or to avoid or reduce impacts are: 17 TO BE COMPLETED BY APPLICANT EVALUATION FOR AGENCY USE ONLY 5. How would the proposal be likely to affect land and shoreline use,including whether it would allow or encourage land or shoreline uses incompatible with existing plans? Proposed measures to avoid or reduce shoreline and land use impacts are: 6. I low would the proposal be likely to increase demands on transportation or public services and utilities? Proposed measures to reduce or respond to such demand(s)are: 7. Identify,if possible,whether the proposal may conflict with local,state,or federal laws or requirements for the protection of the environment. 18