Federal Register: June 24, 2008 (Volume 73, Number 122)
DOCID: fr24jn08-105 FR Doc E8-14146
TENNESSEE VALLEY AUTHORITY
Tennessee Valley Authority
ACTION: Final Environmental Impact Statement:
DOCUMENT ACTION: Issuance of Record of Decision.
Final Environmental Impact Statement--Rutherford-Williamson- Davidson Power Supply Improvement Project
This notice is provided in accordance with the Council on Environmental Quality's regulations (40 CFR parts 1500 to 1508) and TVA's procedures implementing the National Environmental Policy Act. TVA has decided to implement the preferred alternative identified in its Final Environmental Impact Statement (EIS), RutherfordWilliamson Davidson Power Supply Improvement Project.
In implementing Alternative 2, TVA has decided to construct and operate the new 500kV Rutherford Substation, the 27mile 500kV transmission line between TVAs 500kV Maury Substation and the new Rutherford Substation, the new 9mile 161kV transmission line between the new Rutherford Substation and Middle Tennessee Electric Membership Corporations (MTEMC) Almaville Substation, and the new 15mile 161kV transmission line between the new Rutherford Substation and MTEMCs Christiana Substation.
Rutherford-Williamson-Davidson Power Supply Improvement Project,
TVA owns and operates a system of transmission lines that move electricity throughout the TVA service area, which comprises most of Tennessee and portions of six adjacent states, and to adjacent utilities. The electrical load growth in Rutherford, Williamson, and Maury Counties, Tennessee, will exceed the capacity of the three 500kV substations and several of the 161kV transmission lines serving the area by 2010. Unless action is taken to address this problem, TVAs ability to continue to provide reliable electric service will be degraded and disrupted more frequently and for longer periods. Therefore, TVA needs to increase transmission capacity in this area.
TVA published a Notice of Intent to prepare this EIS in the Federal Register on July 1, 2005. A public scoping meeting was held in July 2005 and attended by about 25 people. Written scoping comments were received from two federal agencies, five state agencies, and several individuals. The Notice of Availability of the Draft EIS was published in the Federal Register on October 5, 2007. TVA held a public meeting on the Draft EIS in October 2007 and accepted comments through mid November. During the development of the EIS, TVA also accepted comments received during an open house held in April 2006 to review potential substation sites and transmission line routes. Comments on the Draft EIS were received from about 22 members of the public and agencies. Appendix B of the Final EIS contains comments TVA received on the Draft EIS and responses to those comments. The Notice of Availability for the Final EIS was published in the Federal Register on April 18, 2008. Alternatives Considered
TVA uses a detailed, comprehensive siting process when it plans its transmission line projects. This is an iterative process that takes into account important environmental and cultural resource features that become constraints on locating proposed lines. Concerns of potentially affected landowners are also actively addressed during this process to reduce or avoid landowner impacts. Broad study corridors are initially defined and potential line routes are subsequently located within the study corridors. Because transmission line rightofways (ROWs) are much narrower than the study corridors, important features that are associated with specific corridors can often be avoided when final line routes are selected. Potential environmental impacts are considered and addressed throughout this siting process with the objective of formulating alternative line routes, including a preferred route, that meet the purpose and need for the proposed action while avoiding or reducing potential impacts. The identified preferred route is then subjected to additional study and analyses. TVA uses a similar process in identifying substation sites.
TVA initially identified four solutions (possible alternatives) to meet the project need. These consisted of: (1) Construct and operate a new 500kV substation in southwest Rutherford County, and construct and operate 2530 miles of 500kV transmission line on vacant, TVAowned ROW, and about 24 miles of new 161kV transmission lines in Rutherford, Maury, and Williamson Counties; (2) construct and operate a new 500kV substation in northeast Williamson County near Brentwood and upgrade about 126 miles of existing 161kV transmission lines in Davidson, Rutherford, Williamson, Sumner, Coffee, Franklin, and Bedford Counties; (3) expand TVAs Pinhook 500kV Substation in southeast Davidson County and upgrade about 134 miles of existing 161kV transmission lines in Davidson, Rutherford, Williamson, Sumner, Wilson, Franklin, and Bedford Counties; and (4) rely on load management and conservation by achieving a reduction in current peak loads by at least 800 megawatts.
Further evaluation of these four potential solutions concluded that only the first would be able to meet the project need. The other two construction solutions had higher overall costs, engineering problems, and problems meeting the 2010 inservice date because of the limited times when the existing transmission lines could be taken out of service for upgrading. Although TVA has recently committed to achieving a systemwide reduction in peak demand growth of 1,400 MW by 2012, the amount of load reduction achievable in the project area by 2010 is not sufficient for the load management/conservation solution to meet the purpose and need.
TVA subsequently addressed two alternatives in further detail in the EIS.
Under Alternative 1, the No Action Alternative, TVA would not
address the forecast highvoltage transmission capacity problem by
implementing any of the potential solutions identified above. This
would make existing electrical supplies unstable and increase likelihood of both planned and
unplanned power outages (brownouts/blackouts) in the Middle Tennessee area as the demand continued to grow.
Under Alternative 2, TVA would construct and operate a new 500kV substation in southwest Rutherford County and associated 500kV and 161kV transmission lines. The preferred locations for these facilities were determined through a rigorous siting process, which included evaluations of natural and cultural features, land use, engineering attributes, and cost. The substation would be located on Coleman Hill Road, about 4 miles east of U.S. Alternate Highway 31/41. A 27mile 500kV transmission line would be built on vacant, TVAowned ROW between TVAs existing Maury 500kV Substation and the proposed new substation. A 9mile 161kV transmission line would connect the new substation to MTEMCs existing Almaville 161kV Substation; 6 miles of this line would be on vacant TVAowned ROW, and the remainder would be on new ROW. A 15mile 161kV transmission line on new ROW would connect the new substation to MTEMCs existing Christiana 161kV Substation.
The proposed substation would occupy a 53acre site and about 40 acres of it would be cleared and graded. Major substation components include 500161kV transformers, circuit breakers, connecting bus work, supporting steel superstructure, ground wire towers, microwave communication tower, spill retention basins and retention pond or tank, switch house, and equipment storage building, enclosed by a security fence. The proposed 500kV transmission line would use selfsupporting galvanized, laced steel structures about 85 to 125 feet tall. The average distance between structures would be about 1000 feet. The electrical conductors would consist of three sets of three cables suspended beneath the structure crossarms by insulators. The proposed 161kV transmission lines would use either single or double steelpole structures 80 to 110 feet tall and three singlecable conductors suspended beneath crossarms by insulators.
Most of the ROW for the 500kV transmission line would be 175 feet wide; about two miles of the ROW near the proposed substation would be 425 feet wide to accommodate parallel lower voltage lines. For ROW it does not already own, TVA would purchase easements from landowners. Because of the need to maintain adequate clearance between tall vegetation and the transmission line conductors, as well as to provide access for construction equipment, most trees and shrubs would initially be removed from the entire width of the ROW. Trees outside of the ROW which are tall enough to pass within 10 feet of a conductor if they fell towards the line would also be removed. Following line construction, the ROW would be revegetated with lowgrowing plants. The ROW can be used by the landowner for many purposes that do not interfere with the maintenance and operation of the line. TVA would periodically inspect and conduct maintenance activities on the completed line. The major maintenance activity is vegetation management, conducted to maintain adequate clearance around the conductors. This would consist of both felling tall trees adjacent to the ROW and control of vegetation within the ROW. Management of vegetation within the ROW would use an integrated vegetation management approach based primarily on mechanical mowing and herbicide application.
Comments on the Final EIS
TVA received comments on the Final EIS from two State and two Federal Government agencies. The Environmental Protection Agency (EPA) requested a comparison of the number of stream crossings potentially affected by the various alternative solutions. Although TVA did not conduct detailed field surveys of the Pinhook and Brentwood alternative solutions and thus cannot compare the number of potentially affected stream crossings with the same accuracy available for the Rutherford solution, the Pinhook and Brentwood solutions would potentially affect more stream crossings because they both involve over twice the length of transmission lines. The potential impacts to individual stream crossings under the Pinhook and Brentwood solutions, however, would likely be less because the transmission lines and most of the potential access roads already exist and there would be little to no clearing of new ROWs.
EPA commented on the discussion of potential impacts to wetlands in the Final EIS and noted that conversion of forested wetlands is impactful given the loss of forest habitat and fragmentation of contiguous habitat. TVA agrees with this and notes that the 2.3 acres of forested wetlands that would be converted to scrubshrub wetlands under the selected alternative occur is several disjunct tracts associated with previously fragmented forests.
EPA requested additional information on the anticipated relocation and proximity of homes, schools, and churches to the proposed transmission lines, as well as the potential environmental justice impacts. Two mobile homes and one occupied house occur entirely within the TVAowned ROW to be used for the 500kV line, and a vacant brick house is partially within this ROW. All of these buildings would be relocated. Two fairly new brick houses slightly extend onto this ROW; TVA has determined that they would not have to be removed and will likely issue their owners a permit for the occupancy of the ROW and add an associated covenant to their deeds. One vacant house in a state of disrepair is on one of the 161kV FOWs and would be removed. No occupied buildings are on or in the immediate vicinity of the substation site. Six churches occur near the route of the 500kV line; their closest and average distances from the ROW are 500 and 2,500 feet, respectively. The closest school to any of the facilities is an elementary school 3,000 feet from a 161kV line. The closest churches are 400 and 1,200 feet from a 161kV line. Relative to the three project area counties, the proportions of the overall population of the 12 adjacent surrounding counties classified as minority or below the poverty level vary greatly and are, on average, higher.
EPA requested spot monitoring of electromagnetic fields (EMF) in the vicinity of nearby residences. TVA does not intend to conduct EMF monitoring; TVA will, however, measure EMF field strength if requested to do so by adjacent property owners. Based on the design of the 500kV transmission line and EMF measurements at other similar lines, TVA expects the EMF field strength under the maximum design electrical load at the edge of the 500kV ROW to be significantly less than the Florida standards of 150 milligauss for lines 230kV or less and 200 milligauss for lines 500kV lines or more cited in the Final EIS.
The Department of the Interior (DOI), Office of Environmental
Policy and Compliance resubmitted the comments it had sent on the Draft
EIS and which TVA had inadvertently failed to address in the Final EIS.
DOI requested supporting references for many statements of fact and
field survey descriptions. DOI also requested more specific information
on the implementation of best management practices(BMPs). Some of this
detailed implementation information is listed in Appendices H and J of
the Final EIS, which describe the streamside management zone to be
established along each watercourse. Additional BMP implementation
details are listed in the stormwater pollution prevention plans for the
various project components. TVAs BMP manual, cited as Muncy (1999) in the Final EIS, is
available on the TVA Web site, www.tva.com. Decision
TVA has decided to implement the preferred alternative identified in the Final EIS, Alternative 2. Of the two alternatives evaluated in the Final EIS, Alternative 1No Action and Alternative 2, only Alternative 2 would meet the purpose and need. TVA used an iterative process to define Alternative 2; this process first considered other potential solutions and then considered various potential alternative substation locations and transmission line routes for the preferred alternative. The substation location and transmission line routes were identified as part of Alternative 2 after being evaluated for engineering and construction, ecological, cultural, line length, and land use criteria. The substation site and transmission line routes were then further modified to minimize effects on individual landowners as well as effects on natural and cultural resources. This effort continued TVAs consideration of potential environmental impacts that occurred during the consideration of other possible solutions (alternatives) to the purpose and need here.
The Tennessee State Historic Preservation Officer has concurred with TVAs determination that Alternative 2, with the implementation of mitigation measures described in a Memorandum of Agreement and other measures listed in the Final EIS, would not adversely affect any archaeological or historic sites eligible for or listed in the National Register of Historic Places. The U.S. Fish and Wildlife Service has concurred with TVAs determination that Alternative 2, with the implementation of mitigation measures listed in the Final EIS, would not adversely affect species listed under the Endangered Species Act or adversely modify designated critical habitat.
Environmentally Preferred Alternative
Alternative 1 No Action is the environmentally preferred alternative because the impacts associated with constructing and operating the substation and associated transmission lines would not occur. This alternative, however, would result in the risk of the loss of electrical service to a large area of Middle Tennessee with a total load of over 4000 megawatts and is considered unreasonable. The loss of this electrical service would result in social and economic impacts.
Alternative 2 has been designed to minimize environmental impacts as much as is feasible. While some or all of the other three potential solutions analyzed early in the development of this project could have resulted in less environmental impacts than Alternative 2, none of these solutions would have met the purpose and need and thus they were not considered reasonable alternatives.
For the reasons discussed in the Final EIS and summarized here, TVA is committing to the following measures to avoid, reduce, or mitigate the potential environmental impacts associated with these actions:
(e.g., mowing). Herbicides will not be used in this area.
Dated: June 5, 2008.
Jacinda B. Woodword,
Interim Vice President, Electric System Projects.
[FR Doc. E814146 Filed 62308; 8:45 am]
BILLING CODE 812008P
FOR FURTHER INFORMATION CONTACT
Anita E. Masters, Senior NEPA Specialist, Environmental Stewardship and Policy, Tennessee Valley Authority, 1101 Market Street, LP 5U, Chattanooga, Tennessee 37402; telephone (423) 7518697 or email email@example.com.