Lower Cumberland and Tennessee Rivers, Kentucky Lock Addition Project, Final Supplement 1 Environmental Impact Statement, Department of the Army, United States Army Corps of Engineers

AGENCY:

Tennessee Valley Authority.

ACTION:

Adoption of Final Supplement 1 Environmental Impact Statement and issuance of record of decision.

SUMMARY:

In accordance with the Council on Environmental Quality's regulations (40 CFR parts 1500 to 1508) and the Tennessee Valley Authority's (TVA) procedures for implementing the National Environmental Policy Act (NEPA), TVA has decided to adopt the Final Supplement 1 Environmental Impact Statement (FSEIS) issued by the United States Army Corps of Engineers (USACE) in May 2001. The FSEIS, entitled “Lower Cumberland and Tennessee Rivers, Kentucky Lock Addition Project,” was filed with the Environmental Protection Agency on May 31, 2001. It addresses modifications and design changes to the approved Lock Addition Project not addressed in earlier NEPA reviews. TVA was a cooperating agency in the preparation of the FSEIS because it has responsibility for Kentucky Dam, including preserving the integrity of the dam and its appurtenant lock structures. TVA also has review and approval responsibilities under Section 26a of the TVA Act and property under TVA control that would be affected. TVA has independently reviewed the FSEIS and finds that the statement adequately addresses the comments and suggestions made by TVA in its role as a cooperating agency. Further, TVA has decided to adopt the USACE's Proposed Action Plan identified in the FSEIS. The Proposed Action Plan is the currently recommended project design based on recent engineering studies, hydraulic modeling information, and newly added features. Overall, the design changes and project modifications reduce the environmental impacts of the original project on high quality mussel resources while improving long-term recreation facilities for fishermen and tourists. None of the proposed changes resulted in public controversy.

FOR FURTHER INFORMATION CONTACT:

Linda B. Shipp, Senior NEPA Specialist, Environmental Policy and Planning, Tennessee Valley Authority, 400 West Summit Hill Drive, Mail Stop WT 8C, Knoxville, Tennessee 37902-1499, telephone (865) 632-3440 or e-mail lboxendine@tva.gov. Copies of the FSEIS may be obtained by writing to Tim Higgs, U.S. Army Corps of Engineers, Nashville District, PO Box 1070 (PM-P), Nashville, Tennessee 73202-1070, telephone (615) 736-7863 or e-mail Timothy.A.Higgs@usace.army.mil.

SUPPLEMENTARY INFORMATION:

The Kentucky Lock and Dam (L&D) project is located in Marshall and Livingston Counties in western Kentucky at Tennessee River Mile 22.4. The project is part of the Kentucky-Barkley Reservoirs' navigation system. The originally approved design for the Lock Addition Project was evaluated in a Final Feasibility Study and Final Environmental Impact Statement (FS/FEIS) completed by USACE on March 13, 1992. In its adoption of the FS/FEIS and issuance of a Record of Decision (ROD) on September 30, 1999, TVA adopted the USACE's preferred alternative, Alternative Plan A. Alternative Plan A recommended the construction of a second and main 110-foot-wide by 1200-foot-long navigation lock chamber and related features at the existing Kentucky L&D to improve the capacity and efficiency of the navigation system. The project was authorized by section 101(a)(13) of the Water Resources Development Act of 1996, and funding to initiate construction was included in the Fiscal Year 1998 Energy and Water Development Appropriations Act.

In recommending the construction of a new navigation lock chamber at Kentucky Dam, the USACE recognized that additional engineering evaluations and hydraulic modeling studies would be required before some features, such as a possible navigation training dike, could be designed. Further, USACE recognized that those modified project components would be addressed in subsequent NEPA documents, tiered from the 1992 FEIS. The FSEIS was prepared to address the project changes not covered by previous NEPA documents.

Alternatives Considered

Two broad plans were considered in the FSEIS: A No Action Plan and a Proposed Action Plan. Under the No Action Plan, the project would be implemented as described in the original 1992 FEIS, as modified in a subsequent October 1999 Environmental Decision Record on the relocation of transmission structures and a March 2000 Environmental Assessment on the relocation of the U.S. Highway 62/641 bridge off Kentucky L&D. Under the Proposed Action Plan, the previously approved project would be implemented with the following design changes and modifications:

• Relocation of the new lock upstream about 200 feet and toward the river about 20 feet.
• Modification of construction methods to reduce the size of areas within cofferdams and to construct more features in the “wet.”
• Construction of a non-public, temporary access road from the main lock area to the Vulcan Disposal Area.
• Mitigation for the loss of the TVA Taylor Park Campground (TPC), temporarily closed by TVA in 1997, through construction of facilities for use by fishermen. These new or modified facilities include: A new lock visitors' center, Powerhouse Island fishing pier, additional Powerhouse Island parking and restroom facilities, west bank fishing pier, and improvements to existing coffer cell.
• Placement of fill up to elevation of contour 385 feet in the TPC area during construction and possibly permanently.
• Mitigation for closure of the east bank boat ramp by constructing a new public boat ramp and courtesy dock in an expanded west bank boat basin for use after construction.
• Use of the expanded boat basin for contractor activities during construction.
• Refinements in some upstream lock features and the approach channel.
• Refinements in some downstream lock features and the approach channel.
• Modification of the size and location of the navigation training dike off Powerhouse Island to improve commercial navigation conditions.
• Mitigation for construction-related closures of the west bank by construction of two fishing jetties along the downstream part of the west bank shoreline.
• Elimination of placement of excavated or dredged material on the east bank between Russell Creek and the Interstate 24 bridge.
• Elimination of the aquatic disposal site at Tennessee River Mile 19.9.

All of the items listed above were determined to be independent features, each of which could be dropped from the project without jeopardizing the construction of the new lock chamber or any of the other independent features. In addition, utility lines (including water, sewer, power, and telephone) associated with those features will be constructed and/or relocated within the project boundaries.

The USACE used a 1:100 scale physical model of Kentucky L&D at its Engineering Research and Development Center to evaluate alternative lock orientations and the design of the navigation and spillway training dikes. The model also was used to develop designs of project facilities that would have minimal environmental impacts. The proposed upstream lock location was selected because it reduced construction costs and environmental impacts by reducing previously planned downstream channel and bank modifications. Modeling determined that bank excavations and in-water excavations to widen the downstream navigation channel were not required. With the reduced volume of wet material requiring disposal, the need for an aquatic disposal site at Tennessee River Mile 19.9 was eliminated. In addition, the need for placing rock along the east bank between Russell Creek and the Interstate 24 bridge also was eliminated.

Alternative locations for replacement of the fisherman access intended to be provided by the east bank boat ramp included other east bank locations, expansion of the existing west bank ramp (as proposed in the 1992 FEIS), and construction of a new ramp in an expanded west bank boat basin. Other east bank locations were dropped due to environmental conflicts (extensive mussel beds) and safety concerns (proximity to lock approach channel). The location of the new ramp in the expanded boat basin was selected because it provided both improved recreational facilities and easy construction access to the river. Alternative contractor ramp locations upstream of the basin in areas with known higher density of mussels were dropped during preliminary scoping discussions with the resources agencies.

Basis for Decision

Like the USACE, TVA has decided to adopt the Proposed Action Plan because it reduces many environmental impacts of the earlier design, including mitigating unavoidable recreational impacts, reducing impacts to listed and non-listed mussel species, and improving recreational fishing. None of the changes resulted in public controversy. The Proposed Action Plan is the environmentally preferable alternative.

Environmental Consequences and Mitigation

As with the preparation of the 1992 FEIS, the issues of major concern for the Supplemental Environmental Impact Statement (SEIS) were impacts to the high quality mussel beds downstream of the L&D and impacts of construction activities on recreation fishing in the tailwater area. Refinements to the lock design have lessened the degree of in-stream work, such as bank excavation and channel dredging, as well as eliminating the need for placement of material along about 3000 linear feet of the right bank from Russell Creek to the Interstate 24 bridge. Construction techniques were modified to reduce the area to be dewatered behind cofferdams. Proposed techniques for building the lower approach wall call for some features (slurry wall and drilled shafts) to be constructed in the “wet.” Much of the lower guidewall would be constructed on a working platform typically 5 feet above normal water levels. These changes are expected to reduce potential mussel impacts.

Recreational facilities closed or displaced by construction activities are being mitigated according to plans that have been coordinated with the public and resource agencies. Additional recreational and tailwater fishing facilities are being constructed with funds previously allocated to mitigate the closure of the TVA TPC, including the lock visitors' center, two fishing piers, and additional parking and restroom facilities. As mitigation for the loss of public access to the west bank of the tailwater for 5-8 years during construction, west bank jetties are being constructed that will provide additional shoreline fishing areas downstream from the construction site. As mitigation for the loss of the east bank boat ramp, a new ramp and courtesy dock will be constructed in the expanded west bank boat basin for post-construction public use.

Relocation and construction of utility lines (including water, sewer, power, and telephone), associated with changes in project design, although not directly addressed in the SEIS, are within the project construction area evaluated in the FSEIS. Most of the proposed utility lines are along an existing right-of-way. As with overall project construction, best management practices will be used to minimize erosion impacts. Therefore, impacts of utility line construction and/or relocation will be minor and localized.

All structures displacing aquatic habitat have been designed to the minimum size necessary to achieve the targeted effects (i.e., addressing river eddy formations). The navigation training dike, spillway training dikes, and the west bank fishing jetties will displace existing river bottom habitat; however, mussel relocation will be conducted for the navigation training dike and west bank jetties to reduce the direct impacts to these resources. The west bank jetties will result in some permanent loss of quality mussel habitat; however, both of those structures should provide long-term improvements for fisheries habitat and benthic macroinvertebrate populations. The structures are to be composed of rock containing minimal amounts of fine material so that objectionable turbidity would not be generated during the construction period. Visual turbidity monitoring will be provided to ensure that in-stream activities do not generate objectionable turbidity.

Overall, the Proposed Action Plan reduces construction impacts of the original project design while improving long-term recreation facilities for fishermen and tourists. The environmental commitments presented in the FSEIS for the Proposed Action Plan include:

• Construction sequencing will be implemented to minimize some project impacts. The west bank fishing jetties would be constructed early to offset impacts from closing areas of the west bank upstream of the boat basin to public access.
• Seasonal restrictions on in-stream, bottom-disturbing activities, such as blasting, dredging, and fill placement, to protect fish spawning. For the tailwater, this seasonal restriction is during February and March; in the headwater, the restricted period is mid-April to mid-June.
• Active construction areas are to be cordoned off to protect the general public. This would include the west bank above the existing boat basin and localized areas on the river and reservoir during active construction of in-water features.
• Escort tugs will be required during active construction of the lock guidewalls and approach dredging to protect both construction crews and traffic entering/exiting the lock.
• Conducting in-stream activities during low-flow periods, where applicable.
• Visual turbidity monitoring during in-stream activities.
• Use of a weighted silt curtain during construction of the expanded west bank boat basin.
• Use of rock with minimal fines for construction of in-stream structures, such as dikes and jetties.
• Relocation of abundant mussel resources where they occur at in-water construction sites.
• Notification of Kentucky Department of Fish and Wildlife Resources during blasting activities for monitoring potential fish kills.
• Proper control of fugitive dust and tracking of sediment onto public roads.
• Compliance with solid waste regulations for disposal of demolition and construction-related wastes.
• If cultural resources are encountered, work is to stop until the site is investigated by a qualified archaeologist. The existing “protective” layer of fill at archaeological site 15Lv12 will not be modified. The berm separating site 15Lv12 from the Vulcan Disposal Area Haul Road also is to remain undisturbed.
• Stabilization of all disturbed areas after construction including use of native plants where areas are not to be mowed or manicured.
• Wetland mitigation for the entire Lock Addition Project, including the 0.11 acres associated with the Vulcan Disposal Area Haul Road, will be completed at a site in Benton, Kentucky. The wetland mitigation site will be monitored to ensure successful restoration of the hydrology and the establishment of wetland vegetation.
• Restoration of the Livingston County Trail System after construction use of the Vulcan Disposal Area Haul Road.

Further, as stated in the USACE's ROD: “Compliance with applicable environmental review and consultation requirements has been accomplished through the development of the FSEIS. The FSEIS documents consideration and compliance with the Clean Water Act; the Endangered Species Act; the National Environmental Policy Act; the National Historic Preservation Act; Executive Order 11988 (Floodplain Management); Executive Order 12898 (Environmental Justice); Executive Order 11990 (Protection of Wetlands); Section 504 of the Rehabilitation Act of 1973 and the Architectural Barriers Act of 1968, and other applicable environmental protection statutes, regulations, and orders. * * *”