[Federal Register Volume 60, Number 97 (Friday, May 19, 1995)]
[Notices]
[Pages 26913-26914]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 95-12322]
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TENNESSEE VALLEY AUTHORITY
Limestone 500-kV Substation and Transmission Line
AGENCY: Tennessee Valley Authority.
ACTION: Notice of no practicable alternative to impacting wetlands.
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SUMMARY: The Tennessee Valley Authority (TVA) proposes to initially
construct three transmission lines connecting to TVA's new 500-kV
substation (under construction) at a site in eastern Limestone County,
Alabama. An environmental assessment, in accordance with the National
Environmental Policy Act, is being prepared. This proposal will result
in the disturbance of about 11.8 acres of wetlands as a result of
handclearing. No structures would be placed in the wetlands. Consistent
with the Executive Order 11990 ``Protection of Wetlands'' and TVA's
Wetlands Procedure, it has been determined that no practicable
alternative exists. TVA is requesting public comment on the impact to
wetlands.
DATES: TVA will consider all relevant comments received by June 2, 1995
before a final decision is made on the proposal.
ADDRESSES: Any comments on this proposal should be addressed to Dale
Wilhelm, National Environmental Policy Act Liaison, Tennessee Valley
Authority, 400 West Summit Hill Drive, Knoxville, Tennessee 37902.
FOR FURTHER INFORMATION CONTACT:
For additional information on this action, call Hugh S. Barger,
Transmission and Power Supply, Tennessee Valley Authority at (615) 751-
3131.
SUPPLEMENTARY INFORMATION: TVA supplies power over its bulk 500-kV
system to north central Alabama through its Madison and Trinity 500-kV
substations. Twice in the past 16 years the Madison substation has been
virtually isolated from large portions of the transmission network when
the Huntsville area transmission system was devastated by tornadoes.
However, available bulk power system backup prevented lengthy
widespread blackouts..
System contingency studies show that by the summer of 1996
isolation or failure of the 500-kV transformer bank at Madison during
peak demand would result in a loss of electric service over a wide
area. Additionally, by the summer of 1997, loss of the 500-kV
transformer bank at Trinity would result in the loss of service to
sections of the area served by this substation. Other
[[Page 26914]] elements of the existing transmission system could not
prevent these single-contingency losses.
TVA will finish constructing a new 500-kV substation by the summer
of 1996 on a site in eastern Limestone county, Alabama. Initially three
transmission lines would be connected into the new substation:
1. The existing Browns Ferry-Madison No. 2 500-kV Transmission Line
would be looped about 500 feet into the substation. The existing 500-kV
line crosses the proposed substation site and no new right-of-way will
be required.
2. The existing Athens-North Huntsville 161-kV Transmission Line would
also be looped into the new substation by building a new double-circuit
transmission line about 4.5 miles on 100 feet of new right-of-way
adjacent to an existing transmission line corridor and 0.4 miles on new
right-of-way 100 feet wide (58.9 total acres). An additional 1.5 miles
would be underbuilt on rebuilt 500-kV towers in the Browns Ferry-
Madison and Trinity-Maury 500-kV lines. No new right-of-way would be
required in these sections.
3. A new 161-kV transmission line would be built from the Limestone
substation to the Jetport, Alabama, substation in Madison County, a
distance of about 9 miles. Approximately 4 miles of the line would be
new construction of 5 miles of the existing General Motors-Jetport 161-
kV line as a single steel pole, double-circuit 161-kV line on existing
right-of-way.
Construction of the proposed transmission lines would result in
right-of-way clearing and vegetation removal affecting approximately
11.8 acres of wetlands. No structures would be placed within the
wetlands. Following construction. vegetation on these wetland rights-
of-way would be managed so as to impede normal successional patterns.
This successional intervention on forested wetlands could worsen
impacts of previous clearing. Other wetland values an functions
unrelated to forest canopy vegetation would remain intact through use
of Best Management Practices (BMPs) for construction and maintenance.
The proposed transmission line routes have been selected to avoid
wetlands as much as practical. Crossings of the Moss Spring and
Beaverdam Swamp are unavoidable and account for most of the wetland
acreage to be impacted.
Wetland impacts would be further minimized through application of
the following BMPs for clearing, construction, and maintenance, on
these forested wetlands. These BMPs would include:
1. Identified wetlands, streams, and drainways would not be modified so
as to alter natural hydrological patterns.
2. Naturally occurring hydric soils would not be disturbed or modified
in any way that would alter their hydrological properties.
3. Right-of-way clearing within forested wetlands would be accomplished
by hand where possible and would be restricted to the minimal width
necessary to allow for construction and operation of the proposed line.
4. If heavy equipment is required to accomplish right-of-way clearing
within forested wetlands, lay-down pads would be used to remove
vegetation and string transmission line cable.
5. Sediment control fencing would be placed downslope from construction
activity to trap sediment and prevent its migration into waterways or
water bodies.
6. Within wetland areas or along streams, stumps would not be uprooted
or removed.
7. Future right-of-way maintenance within identified wetlands would be
conducted during traditionally dry seasons and would avoid the use of
heavy equipment. Chemical maintenance would only be done using
chemicals labeled by the Environmental Protection Agency for wetlands
use.
Dated: May 12, 1995.
Jon M. Loney,
Manager, Environmental Management.
[FR Doc. 95-12322 Filed 5-18-95; 8:45 am]
BILLING CODE 8120-01-M
