NEW YORK STATE DEPARTMENT OF ENVIRONMENTAL CONSERVATION

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1 NEW YORK STATE DEPARTMENT OF ENVIRONMENTAL CONSERVATION

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4 October 17, 2011 Mr. Chris Hogan New York State Department of Environmental Conservation Division of Environmental Permits, 4 th Floor 625 Broadway Albany, New York Re: Additional Information; CPV Valley Energy Center; DEC #: /00005; Wawayanda (T), Orange County Dear Mr. Hogan: This transmittal is in response to the New York State Department of Environmental Conservation s (NYSDEC s) comment letter dated July 9, 2009, regarding the CPV Valley Energy Center s Application for Permit pursuant to 6 NYCRR Part 663 (Freshwater Wetlands). Prior to responding to NYSDEC s comments, CPV Valley was awaiting the results of the additional ecological field surveys conducted at the Project site so that thorough and complete responses could be provided to the NYSDEC and U.S. Army Corps of Engineers comments on the Joint Wetlands Permit Application. Since receipt of the NYSDEC s comments, CPV Valley has completed additional ecological field surveys as part of the SEQRA process. The ecological field surveys were conducted in the spring through fall of 2009, and included additional evaluation of vernal pools, surveys for the potential summer roosting habitat of the Indiana Bat, stream habitat assessment, and detailed surveys for rare plant species. The results of the surveys were submitted to the Town of Wawayanda Planning Board in November 2009 and then subsequently approved by the Planning Board and its consultants. The report documenting the survey results, entitled Spring and Summer 2009 Ecological Field Survey Report was distributed to all involved and interested agencies and made available to the general public in March 2010 as part of the SEQRA process. The report was provided to the NYSDEC on March 8, 2010 for its review and comment. In addition, CPV Valley is currently in the process of working with the City of Middletown and property owners in refining the location of the end portion of the Project s process water/wastewater line and connection to the City of Middletown Sewage Treatment Plant. The portion along Dolsontown Road and connection to the City of Middletown Sewage Treatment Plant is currently being refined pending discussions with the property owners. The revised plans for the Joint Wetlands Permit Application will be submitted to DEC and the U.S. Army Corps of Engineers once this segment of the water line route has been confirmed. As discussed at our meeting on January 13, 2011, CPV was at that time proceeding through the New York State Independent System Operator (NYISO) electrical interconnection process. The design of the interconnection, and specifically whether underground versus overhead, was a subject of substantial L

5 Mr. Chris Hogan Page 2 of 7 debate with NYPA, NYSEG, and CHG&E. Until the interconnection design was accepted and approved by all of these affected parties, CPV was not able to proceed with finalizing the interconnection and evaluating its impacts. In September 2011, the NYISO finalized the interconnection study and confirmed the underground option would be acceptable. This process, which has been a reason for delay in responding to the NYSDEC comments, is now concluded and CPV is proceeding with the underground interconnection design. Based on the information compiled, responses to the NYSDEC s July 9, 2009 comments are provided below. NYSDEC s comments are presented in italics, with the responses following each comment in normal type. Consistent with the comments made in the July 9, 2009 DEC letter, CPV has pursued a goal of avoiding impacts to wetlands where practicable. If wetland impacts could not be avoided, the objective was to minimize the area impacted and to develop companion mitigation measures. Where potential impacts could not be avoided, design efforts were pursued to test alternative physical layouts for plant structures and alternative routing rights-of-way for linear project components. NYSDEC COMMENT: 1) Alternative Analysis. The biggest impact to wetlands is the clearing and disturbance through forested wetland for the transmission line connection to the grid. The application does not provide a detailed enough alternative analysis for this portion of the project. As required by regulation, you must demonstrate no practicable alternative to this impact on the resource. For instance, page 5-2 of the application refers to a Figure 19-1 that shows routing options. Staff could not locate this diagram in the application. The application should evaluate alternatives such as addressing placing the transmission line along Route 6 and then crossing Route 17M. The application also does not address placing the transmission line underground. The alternative analysis should address in detail issues such as, but not limited to, cost, electrical losses, and visual impacts. RESPONSE: The referenced Figure 19-1 showing the electric line routing options was inadvertently omitted from the application. This figure is attached. Summary discussion regarding placing electric transmission line along Route 6 and underground within the Project site is provided below: Placing Electrical Transmission Line Underground along Route 6: The ability to install the electric transmission line underground within the Route 6 right-of-way was evaluated in consideration of the following factors: Current use of right-of-way and width: The right-of-way width on Route 6 along the frontage of the Project site (south shoulder of Route 6) varies from 12 to 20 feet from the edge of the pavement to the right-of-way line. Two natural gas lines, an 8 inch line and a 12 inch line, are located within this right-of-way. The path followed by these natural gas lines is irregular and not straight within the right-of-way. There are also utilities located on the north shoulder of Route 6, including the Town s water line. There are two natural gas lines located about 400 feet east of Kirbytown Road; one runs along Route 6 to the east and the other bisects it. As-built survey drawings are not available for the utilities located to the north; therefore, their exact locations are unknown. L

6 Mr. Chris Hogan Page 3 of 7 Facility transmission line space requirement: An underground 345 kv transmission line and encasing duct bank structure requires a width of 6 feet. In addition, an underground transmission line requires a 20 foot wide right-of-way to accommodate construction and maintenance. With the gas lines located in the south shoulder of Route 6, there is not enough space to accommodate the addition of the transmission line and associated duct bank. In addition, engineering design criteria require that high voltage electric lines and natural gas lines that are collocated in a common right-of-way provide for adequate physical separation and cathodic protection for purposes of safety. This safety requirement further reinforces the infeasibility of use of the Route 6 right-of-way. Therefore, instead of the electrical lines, the Project s water/wastewater lines were chosen to be located within the south shoulder of Route 6 due to their relatively small size and to minimize further disturbances in the wetland along the southern boundary of the property. Similarly, available information regarding the north side of Route 6 shows inadequate right-ofway width due to the Town water main and natural gas lines. Placing Electric Transmission Line Underground within the Project Site: As mentioned above, the NYISO concluded the interconnection study process and accepted the underground interconnection option. The electric transmission line will be placed underground from the project site proper and extended to the GIS substation located adjacent to NYPA s 345kV Marcy South transmission line. This point of interconnection with NYPA is the same point of interconnection depicted in the DEIS. Environmental Considerations The underground option would consist of the transmission cables being placed underground, and therefore, there would be minimal permanent disturbance, which would be associated with manholes located along the path of the underground cables. There may be up to three manhole access points approximately 20 feet long by 9 feet wide by 8.5 feet deep in dimension. There will be temporary land disturbance associated with the installation of underground cable, including uplands, a roadway road shoulder, wetlands (NYSDEC-mapped and federal-only wetlands), and two streams. The installation process will entail open cut trenching and backfilling. The disturbed non-woody vegetation within the maintained electrical right-of-way will be allowed to return to its natural state, and will be seeded for stabilization as necessary. The on-site underground electrical transmission route alternative would follow the same general route as the originally proposed overhead route. The center line has been moved slightly from that presented in the DEIS to avoid impacting a vernal pool. A 75 foot construction corridor will be established, within which vegetation will be cleared for trenching, soil stockpiling, conduit assembly and operation of construction equipment. The construction corridor will occur within approximately 2077 linear feet of wetlands (240 feet of which are currently forested). Use of this construction corridor would result in approximately 3.56 acres of temporary impacts and of this approximately 0.46 acres of permanent impacts to wetlands in the form of conversion of forested to non-forested vegetation. These approximate wetland impact numbers will be refined once the revised site plan is completed. This is a significant reduction from the above ground option that consisted of a 130 foot right-of-way width resulting in approximately 6.2 acres of temporary L

7 Mr. Chris Hogan Page 4 of 7 wetland impacts, and 0.92 acres of permanent impacts to wetlands in the form of conversion of forested to non-forested vegetation. A permanent corridor of 20 feet will be maintained for the electric transmission line within the site proper (i.e., from the switching station to the crossing of Carpenter Creek at Route 17M). The interconnect would then continue north, parallel to Route 17M within a roadside corridor, cross beneath the Route 6 interchange, and connect to the GIS building and then to the NYPA 345 kilovolt (kv) lines. Prior to the start of construction, erosion and sedimentation (E&S) controls will be installed along the construction corridor. A 12 foot wide by 4 foot deep trench will be excavated for electrical conduits. A temporary access road using swamp mats and possibly gravel road fill sufficient to accommodate large cement mixers or dump trucks for trench backfill will be installed and maintained for conduit installation. Topsoil excavated from the trench will be stockpiled within the construction corridor so that it may be placed back over the completed electric transmission line. However, most of the subsoil from the trench will be removed from site in order to backfill the trench with suitable materials. E&S controls will be placed around temporary soil stockpiles to avoid sedimentation of surrounding wetlands. The trench will be dewatered as necessary during conduit installation. Trench water will be directed to temporary above-ground basins comprised of haybales and filter fabric, which will allow water to infiltrate back into the ground. The underground trench would cross the unnamed tributary to Carpenter Creek, south of where it joins Carpenter Creek, requiring 600 square feet (0.01 acre) of temporary impact to the stream and its banks. Open cut construction methods will be used. The methodology for stream crossings is outlined in the Joint Wetlands Application for Permit. Following construction, the trench area and the disturbed corridor will be re-graded, stabilized, and revegetated. The stream bed and banks will also require restoration to pre-existing grades, with bank stabilization measures and monitoring to prevent soil erosion. Wetland and stream restoration monitoring will be implemented according to permit conditions. Visual Impacts The underground installation of the electric wires eliminates the visual impacts of the overhead transmission wires and supporting pole structures. Once the transmission line is constructed, only the maintained corridor will be visible. Placing Electric Transmission Line Adjacent to Interstate 84 (I-84) The alternative of abutting the electrical interconnect as close to Interstate 84 (I-84) as possible was also evaluated. The field surveys conducted of the site indicated the presence of wetland areas along the edge of the NYSDOT controlled right-of-way for I-84 extending eastward from near the edge of the generating facility footprint, all the way to Route 17M. The impacted wetland area associated with pursuit of an east to west right-of-way along I-84 is significantly greater than that of the preferred alignment. L

8 Mr. Chris Hogan Page 5 of 7 NYSDEC COMMENT: 2) Minimization of Impacts. Once the department has determined there are no reasonable alternatives, it must determine impacts to the wetlands have been minimized. In that regard, the application must demonstrate that a 130 foot wide ROW is necessary. The application indicates that the towers are 130 feet in height. The presumed purpose of clearing the ROW is to prevent trees from taking out the line. That being the case, it does not seem that a 130 foot ROW is necessary with towers of that height? The area of the transmission line construction is red maple swamp and if the trees are not greater than 60 feet in height which also makes the 130 foot ROW seems excessive. In addition, the application should address topping the trees in the ROW rather than cutting them to the ground in order to minimize wetland impacts. RESPONSE: Due to the transmission line placement underground, any impacts have been significantly minimized through the elimination of transmission towers and a reduction in the right-of-way width. The width of the permanent electrical right-of-way has been reduced to 20 feet. NYSDEC COMMENT: 3) If, based on the application, the Department determines clearing through the wetland is justified; a plan will need to be submitted showing the route and limit of disturbance. This can be submitted as part of the response to this information request, if it is available. RESPONSE: The revised plan will be submitted to the DEC and will show the route and limit of disturbance, as well as specific crossing impacts at each wetland area. The attached figure shows the reduced right-of-way width on an aerial photograph. NYSDEC COMMENT: 4) Mitigation: The application does not include mitigation for the conversion of forest to scrub-shrub wetland. The Department considers this to be a permanent impact. RESPONSE: The Wetland Mitigation Plan that was submitted with the original Joint Application has been revised to include mitigation for the conversion of forest to scrub-shrub wetland as a permanent impact. The revised Wetland Mitigation Plan, along with additional soils and groundwater information will be provided in the forthcoming submittal to DEC. Conversion of forested wetlands to non-forested wetland within the electrical interconnect will be compensated by creating a permanent forested riparian buffer along Carpenter Creek within the site boundaries. This riparian buffer planting area will be approximately 70 feet wide (25 to 30 feet on either side of the bank, not including the stream width), and extend for most of the entire length of Carpenter Creek on the site, about 4,000 linear feet. The riparian buffer area will therefore encompass approximately 6.4 acres on the site. The area will be planted with tree seedlings including flood-tolerant species suitable for riparian zones and valuable for mast production and cover habitat species such as pin oak (Quercus palustris), silver maple (Acer saccharinum) and quaking aspen (Populus tremuloides). The riparian buffer area will be permanently protected from clearing or access from agricultural activities L

9 Mr. Chris Hogan Page 6 of 7 through placement of markers along the field edges, and through direct control and management of the land leases by CPV Valley. NYSDEC COMMENT: 4) Mitigation: (continued) In addition the Department as part of the approval for the Project will require the project sponsor to submit an Invasive Species Management Plan for the wetlands on the property. The plan will need to address removal of any existing invasive species and plan to manage invasive species in the future. RESPONSE: Invasive species in both wetland and upland communities were observed on the site. Within the emergent marsh wetland communities, stands of common reed and purple loosestrife were noted. Common reed is located within the cropland/row crops and mowed roadside/path communities situated in disturbed areas that are adjacent to the I-84 highway right-of-way. Purple loosestrife was observed in the shallow emergent marsh on the eastern end of the site, closest to Route 17M and the I-84 westbound on-ramp. Upland forested and successional areas were observed to contain Norway maple and tartarian honeysuckle, and both successional upland and forested/shrub swamp wetland communities were observed to contain common buckthorn, multiflora rose and poison ivy. The Project will avoid the introduction and further spread of invasive species to the maximum extent practicable. The Wetland Mitigation Area to be constructed will be planted with native saplings, shrubs and herbaceous vegetation. Seeding of the new placed soils will be done as soon as possible after final grading of the mitigation area in order to quickly establish herbaceous growth. Any use of supplemental soils or organic mulch within the mitigation area, if required, will be specifically obtained from sources free of invasive species and invasive seed and/or roots. The rapid establishment of native vegetation will lessen the opportunity of invasive species colonization on the site. It is anticipated that all topsoil used for landscaped or restored areas will be from on-site stockpiles. This will contribute to the overall quality control for the construction of the permanent riparian buffer along Carpenter Creek. For control of invasive species within the generating facility site and ecologically sensitive areas such as the wetland mitigation area and wetland/riparian buffers, CPV will employ a multi-tiered invasive species control methodology that may include mechanical, chemical, and biological components as developed and approved by the EPA and NYSDEC. The electrical interconnect line will be controlled and maintained by CPV, or its subcontractor. Routine maintenance will likely include vegetation control by a combination of mechanical cutting and use of herbicides, per NYPA s or New York State s Bulk Power System standards and practices for vegetation management elsewhere on their system. Depending on the vegetative conditions of the particular rightof-way, mechanical cutting and use of herbicides each have benefits, including overall effectiveness and ecological sensitivity, when used in combination over a multi-year cycle. CPV is aware of the ecological sensitivity of wetland areas and will recommend employment only of vegetation control methods suitable for wetlands communities and accepted by the EPA and the state of New York under NYPA s or New York State s Bulk Power System standards for approved vegetative management plan. Part of the management plan would likely include performing vegetative maintenance during the winter. L

10 Mr. Chris Hogan Page 7 of 7 We trust that the information provided above and attached addresses your comments. If you have any additional questions, please contact me at (978) or me at cduncan@trcsolutions.com, or contact Steve Remillard at (781) or sremillard@cpv.com. Sincerely, Colin P. Duncan, CPSS, PWS Senior Soil and Wetland Scientist Attachments cc: Steve Remillard, CPV Valley Brian A. Orzel, U.S. Army Corps of Engineers L

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13 January 6, 2012 Mr. Chris Hogan New York State Department of Environmental Conservation Division of Environmental Permits, 4 th Floor 625 Broadway Albany, New York Mr. Doug Gaugler New York State Department of Environmental Conservation 21 South Putt Corners Rd New Paltz, New York Re: Additional Information; CPV Valley Energy Center Project; DEC # /00005; Wawayanda (T), Orange County Dear Gentlemen: As a follow up to TRC s letter dated October 17, 2011, please find attached the revised plans for the CPV Valley Energy Center Project to support the CPV Valley Energy Center s Application for Permit pursuant to pursuant to 6 NYCRR Part 663 (Freshwater Wetlands), dated July 9, The revised plans, which are included as Attachment A to this letter, address the project refinements that were summarized in TRC s letter dated October 17, 2011, as well as respond to comments from the U.S. Army Corps of Engineers on previous set of plans. The most recent agency correspondence is provided as Attachment B to this letter. If you have any additional questions, please feel free to contact me at (978) or cduncan@trcsolutions.com or contact Steve Remillard at (781) or sremillard@cpv.com. Sincerely yours, Colin P. Duncan, CPSS, PWS Senior Soil and Wetland Scientist Attachments cc: Steve Remillard, CPV L

14 ATTACHMENT A REVISED PLANS WETLANDS PERMIT APPLICATION L