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EA-Administrative Record
Finding of No Significant
Impact (FONSI)
BFN Cooling Tower 3
Replacement
2013-3
SUPPLEMENTAL ENVIRONMENTAL ASSESSMENT AND
FINDING OF NO SIGNIFICANT IMPACT
TENNESSEE VALLEY AUTHORITY
BROWNS FERRY NUCLEAR PLANT COOLING TOWER 3 REPLACEMENT,
LIMESTONE COUNTY, ALABAMA
The Tennessee Valley Authority (TVA) proposes to replace one of its seven existing mechanical
draft cooling towers (MDCT) at the Browns Ferry Nuclear Plant (BFN) with a more modern
tower that includes larger fan motors and a larger cold water basin. TVA would replace the
existing damaged Cooling Tower 3 (CT-3) with a similar 16-cell fiberglass reinforced Plastic
(FRP) cooling tower with similar capacities.
The existing CT-3 partially collapsed in July 2012 and is in an unsafe condition. It is currently in
the process of being demolished and removed from the BFN site. The effects of the CT-3
demolition were addressed in Categorical Exclusion Checklist (CEC) 27427 (Attachment 1),
including the demolition of the north wall of the cooling tower basin. Demolition and cleanup will
take about 3 weeks.
The cooling towers at BFN are especially critical during the hot summer months to provide heat
rejection capacity which reduces the temperature of the cooling water used during power
production. Loss of heat rejection capacity can cause significant plant derates, where the plant
reduces power production that result in increased operating costs and lost revenue. The recent
structural failure of existing CT-3 has reduced the available heat rejection capacity. The
replacement of CT-3 would result in a near full heat rejection capacity being available during
power operations in the summer months. Thus, the tower replacement would help reduce the
duration and frequency of power generation reductions (known as “derates”) at BFN.
On October 28, 2010, TVA issued an Environmental Assessment (EA) for Browns Ferry Nuclear
Plant Cooling Towers Addition and Replacements and a finding of no significant impact (FONSI)
for the replacement of four original MDCTs with larger towers and the construction of an
additional MDCT at BFN. This work was to provide additional and more efficient cooling
capacity needed for current operation and for future increases in power output (known as
“uprates”). The new cooling towers were proposed to help reduce the duration and frequency of
derates at BFN which could increase costs to TVA ratepayers during the summer months.
TVA also completed a Final Supplemental Environmental Impact Statement for Operating
License Renewal of the Browns Ferry Nuclear Plant in 2002. The Final Supplemental
Environmental Impact Statement (SEIS) assessed the impacts of the license renewal for Units 2
and 3 for an additional 20 years of operation beyond their current operating licenses and the
restart, license extension, and uprate of BFN Unit 1. The SEIS considered alternatives for up to
eight cooling towers for BFN, including replacements and new towers. TVA has subsequently
constructed one additional cooling tower.
In consideration of the replacement for CT-3, TVA has reviewed the 2010 EA for the Browns
Ferry Nuclear Plant Cooling Towers Addition and Replacements and the 2002 Final SEIS. The
potential effects of constructing a new cooling tower at the existing CT-3 site that were not
previously addressed are documented in this supplement to the 2010 EA (SEA).
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In addition to the 2002 license renewal SEIS, 2010 cooling tower addition and replacement EA,
and demolition CEC previously mentioned, several environmental reviews have been prepared
for actions related to the construction and operation of additional and replacement cooling
towers at BFN. This SEA supplements the 2010 EA and incorporates by reference the 2002
license renewal SEIS.
Background
BFN is a three-unit General Electric boiling water reactor facility with a capacity of 3,440
megawatts. The units began operation between 1974 and 1977 and six Ecodyne MDCTs were
originally installed at the facility. CT-1, -2, -5, and -6 are the original Ecodyne 16-cell cooling
towers with 200 horsepower (hp) fan motors and are planned for replacement with increased
cell capacity (up to 20 cells). The original CT-3 and -4 were destroyed by fire in 1986 and in
1996 respectively, during a long plant shutdown. CT-3 was replaced in 1996 with the currently
inactive Balcke-Durr 16 cell MDCT which is approximately 14 feet wider than the original
Ecodyne design and with 200 hp fan motors. CT-4 was replaced in 2007 with a Marley (SPX)
16 cell cooling tower to support a Unit 1 restart. CT-4 is also wider and has larger, 250 hp fan
motors. To increase total plant cooling capacity as planned during relicensing, a new cooling
tower, CT-7 was constructed in 2011.
No changes in the total BFN intake flow rate of 1.98 million gallons per minute are proposed and
the intake and discharge volumes would remain the same. Federal, state, and local
environmental authorizations could include additions to the National Pollutant Discharge
Elimination System (NPDES) Permit for discharges of storm water associated with construction
activities and the Storm Water Pollution Prevention Plan (Alabama Department of
Environmental Management [ADEM]) and solid and hazardous waste disposal (Resource
Conservation and Recovery Act [RCRA]; ADEM)
Alternatives
The potential effects of constructing and operating both replacement and new cooling towers
were evaluated in TVA’s 2010 EA. The EA evaluated two alternatives in detail: the No Action
Alternative and the Action Alternative. Under the No Action Alternative, TVA would not have
increased BFN cooling capacity and would neither replace the four cooling towers nor construct
a the new cooling tower (CT-7).
Under the Action Alternative in the 2010 EA, CT -1, -2, -5, and -6 would be replaced with larger
linear MDCTs and one additional 25- to 30-cell linear MDCT would be constructed (CT-7).
Activities included construction of a new discharge channel, modifications to the existing warm
and cold water channels, a pumping station, various pipelines, a gate structure, and overhead
power lines. The Alternative also included the relocation of the Western Perimeter Ditch and
Shaw Road to make room for CT-7, the relocation of underground fiber optic cable and
telephone lines, and improvements to Lawngate and Browns Ferry roads. TVA selected the
Proposed Action Alternative of the 2010 EA. TVA completed the additional cooling tower (CT-7)
in May 2012; replacement of CT -1, -2, -5, and -6 has not yet begun.
The alternatives currently under consideration are the No Action Alternative and the Proposed
Action Alternative. Under the No Action Alternative, TVA would continue with the CT
replacement plan assessed in the 2010 EA. Under the Proposed Action Alternative here, TVA
would continue with that plan, but now would include the replacement of CT-3. The proposed
new CT- 3 would follow the basic concept plans for the replacement of the four other towers
considered in the 2010 EA. With the replacement of CT-3, the potential heat rejection capacity
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that was lost when the cooling tower was taken out of service would become available for future
BFN power operations.
The new CT-3 would be constructed similarly to the collapsed tower, although out of FRP
instead of wood. Sixteen new 250 hp fan motors would be installed. The height of the tower
would be increased by two feet, to a total height of 67 feet, 7.5 inches from the basin to top of
the stack and the cold water basin would be increased in width from 65 feet to 70 feet. The
excavation for the basin prep work would not exceed 48 inches in depth (Attachment 2). The
concrete foundations of the two current switchgears would be rebuilt approximately 30 feet north
of the wider basin. The foundations would be the same size as those for the old tower. The
construction would take approximately 6 months to complete.
Impacts Assessment
Under the No Action Alternative, TVA would continue to operate BFN using the existing cooling
tower system without the capacity of CT-3. The discussion of impacts described in the 2010 EA
under its Proposed Action Alternative would occur under the current No Action Alternative. TVA
would continue to operate the system so as to meet NPDES permit limits, including derating the
plant during the summer as necessary. Extensive summer derates at BFN could increase costs
to TVA ratepayers.
The Proposed Action Alternative would result in similar but greater construction and operational
effects than those described in the 2010 EA. As in the 2010 EA, construction and operational
effects to historic and archeological resources, floodplains and flood risk, endangered and
threatened species, and wetlands are expected to be none or minor. The Alabama State
Historic Preservation Officer concurred with TVA’s determination of no effects to historic
properties for the proposal in the 2010 EA, CT-3 is within the same area of potential effect that
has been extensively disturbed by the construction of BFN, such that no cultural resources
would be affected. Hydrothermal effects of cooling tower operation are expected to be the
same as the former CT-3 tower and would remain protective of aquatic species. The cumulative
effects of replacing CT-3 would be the same as described in the 2010 EA.
Transportation. There would be temporary, minor adverse effects related to transportation
during the construction of CT-3 due to the necessary increase of traffic over local roads by
material deliveries and workers. Construction of CT-3 is expected to require 80 workers at the
peak of construction. Material deliveries during the six month construction period are expected
to average three deliveries per week. Overall, the effects on transportation of the addition of
CT-3 to the proposed action of the 2010 EA are expected to continue to be insignificant.
Noise. The potential for noise impacts from the replacement of cooling towers was addressed
in the license renewal 2002 SEIS. Section 3.19.5 of the SEIS described the current noise
environment as having changed since the plant was constructed, including growth in adjacent
residential populations, an industrial park about 2 miles upstream and across the river, and
barge traffic. None of the alternatives showed potential for adverse impacts to Lakeview
Communities. Alternative 2C in the SEIS, the Enlarged Linear MDCT Option, was assessed as
potentially resulting in noise impacts to Paradise Shores. The SEIS stated that the use of low
noise fans operating at reduced speeds would lower the total predicted noise at Paradise
Shores under the preferred alternative to acceptable noise levels. Subsequent noise analyses
now indicate that background or baseline noise levels without operation of the cooling towers
reach the 59.7 dBA which exceeds EPA’s 55 dBA for residential areas. However, the Federal
Interagency Committee on Noise guidelines at residences and exterior plant boundaries (FICON
guideline) is met when the cooling towers are operating.
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Under the Proposed Action Alternative here, TVA would continue to meet FICON guidelines.
TVA would work with the selected cooling tower vendor to ensure noise attenuating features, as
required, such as low noise fans, lower speed fans, and sound attenuators are included in CT-3
design. Onsite, TVA would comply with Occupation Safety and Health Administration
regulations to protect worker health. As described in the 2010 EA, operational noise levels
would be verified by a qualified acoustical engineer to ensure that the project’s noise level
complies with the applicable levels, and are consistent with previous commitments. Monitoring
is planned to be conducted after the completion of the replacement cooling tower when it is in
operation. In the event that the resulting noise levels are found to exceed the FICON
guidelines, TVA would develop and implement additional acoustical mitigation such as
modifications to fans and motors, or the installation of barriers.
With noise reduction measures included in CT-3 design, noise impacts are expected to continue
to be insignificant. Noise from cooling tower operations would be monitored and mitigated as
identified in the 2010 EA except the EPA guideline would no longer be used.
Visual. The new MDCT would be constructed at the CT-3 site. The existing tower would be
replaced with a slightly taller and wider unit and the new concrete switchgear pad would be
relocated (Attachment 2). The outward appearance of the new unit would be much the same as
the recently constructed CT-7 unit which has the same design and materials
The construction-related impacts on visual resources assessed in 2002, described as temporary
and not significant, bound the potential impacts from the proposed Action Alterative. There
would be no additional operational-related impacts, such as vapor plumes and site lighting. The
primary difference of the proposed action would be the slightly larger size of the new CT-3 unit.
However, the area is already visually cluttered with nuclear plant buildings, roads, and
transmission lines. The proposal would result in some very minor changes to the viewscape,
but the changes would be similar to what is currently seen by observers in the area.
Short-term changes to the visual character would occur within the local area during construction
due to equipment and ground-disturbing activities. However, the proposed action would not
result in environmental impacts significantly different from those identified in the earlier
environmental reviews.
Special Commitments and Mitigation
TVA will implement standard best management practices to reduce the potential for adverse
effects to environmental resources from constructing and operating a replacement for CT-3 at
BFN. To further reduce impacts, TVA will implement the nonroutine mitigation measures
described in the 2010 EA as adjusted to include a CT-3 replacement.
Conclusion and Findings
TVA has determined that the construction and operation of a replacement for CT-3 will not result
in significant adverse impacts, either individually or cumulatively. The 2010 EA and FONSI
remain valid. Consequently, TVA concludes that implementation of this project will not be a
major federal action significantly affecting the environment, subject to the identified mitigation
measures. Accordingly, an EIS is not required.
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December 6, 2012
Date Signed
Charles P. Nicholson, Acting Senior Manager
NEPA Interface
Environmental Permits and Compliance
Tennessee Valley Authority
Attachments
Attachment 1 - CEC 27427
Attachment 2 - Map of Proposed CT 3 Footprint
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Attachment 1 - CEC 27427
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Attachment 2 - CT3 Map
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