[Federal Register Volume 66, Number 4 (Friday, January 5, 2001)]
[Notices]
[Pages 1158-1160]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 01-360]


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NUCLEAR REGULATORY COMMISSION

[Docket Nos. STN 50-454, STN 50-455, STN 50-456 and STN 50-457]


Commonwealth Edison Company, Byron Station, Units 1 and 2, 
Braidwood Station, Units 1 and 2; Environmental Assessment and Finding 
of no Significant Impact

    The U.S. Nuclear Regulatory Commission (NRC) is considering 
issuance of amendments to Facility Operating License Nos. NPF-37, NPF-
66, NPF-72 and NPF-77; issued to Commonwealth Edison Company (ComEd or 
licensee), for operation of Byron Station, Units 1 and 2 (Byron), 
located in Ogle County, Illinois, and Braidwood Station, Units 1 and 2 
(Braidwood), located in Will County, Illinois.

Environmental Assessment

Identification of the Proposed Action

    The proposed action would allow ComEd to increase the maximum 
reactor core power level from 3411 megawatts thermal (MWt) to 3586.6 
MWt, which is an increase of 5 percent of rated core thermal power for 
each unit at Byron Station, Units 1 and 2, and for each unit at 
Braidwood Station, Units 1 and 2. The proposed action is in accordance 
with the licensee's application for amendment dated July 5, 2000, as 
supplemented on November 27, 2000.

The Need for the Proposed Action

    The proposed action permits an increase in the licensed core 
thermal power from 3411 MWt to 3586.6 MWt and for each of the four 
units and provides the flexibility to increase the potential electrical 
output of Byron Station, Units 1 and 2, and Braidwood Station, Units 1 
and 2.

Environmental Impacts of the Proposed Action

    ComEd has submitted an environmental evaluation supporting the 
proposed power uprate and provided a summary of its conclusions 
concerning both the radiological and non-radiological environmental 
impacts of the proposed action.

[[Page 1159]]

Radiological Environmental Assessment: Radwaste Systems

    The reactor coolant contains activated corrosion products, which 
are the result of metallic materials entering the water and being 
activated in the reactor region. Under power uprate conditions, the 
feedwater flow increases with power and the activation rate in the 
reactor region increases with power. The net result may be an increase 
in the activated corrosion product production. However, the evaluation 
has shown that the power uprate will not cause a significant change in 
the types or a significant increase in the amounts of any radiological 
effluent that may be released offsite.
    Non-condensible radioactive gas from the main condenser, along with 
air in-leakage, normally contains activation gases (principally N-16, 
O-19 and N-13) and fission product radioactive noble gases. This is the 
major source of radioactive gas (greater than all other sources 
combined). These non-condensible gases, along with non-radioactive air, 
are continuously removed from the main condensers which discharge into 
the offgas system. The changes in gaseous effluents are small and are 
well within the uncertainty of the calculation of the original limits 
following implementation of the power uprate.
    ComEd has concluded that there will be no significant change in the 
level of controls or methodology used for the processing of radioactive 
effluents; or handling of solid radioactive waste at Byron and 
Braidwood will not be impacted by operation at uprated power 
conditions, and the slight increase in effluents discharged would 
continue to meet the requirements of part 20 of Title 10 of the Code of 
Federal Regulations (10 CFR) and 10 CFR part 50, appendix I. Therefore, 
the power uprate will not appreciably affect the ability to process 
liquid or gaseous radioactive effluents and there are no significant 
environmental effects from radiological releases.

Dose Consideration

    ComEd evaluated the potential effects of power uprate conditions on 
the radiation sources within the plant and the radiation levels during 
normal and post-accident conditions. The original calculations for 
determining the normal operational doses and radiation shielding 
requirements were very conservative and had additional margin assumed 
in the calculations. It was determined that these margins are 
sufficient to accommodate any increases attributed to the five percent 
increase in rated thermal power. The power uprate has no significant 
effect on plant normal operation radiation zones and shielding 
requirements. In addition, the normal operation component of the total 
integrated dose used for radiological equipment qualification (EQ) is 
not affected by the power uprate.
    The power uprate does not involve significant increases in the 
offsite doses to the public from noble gases, airborne particulates, 
iodine, tritium, or liquid effluents. An upper bound analysis for the 
potential impact of the power uprate indicates that the increase in 
radiological releases and resultant dose impact is bounded by the 
percentage increase in the reactor core power. Therefore, the normal 
offsite doses are not significantly affected by operation at the 
uprated power level and remain below the limits of 10 CFR part 20 and 
10 CFR part 50, appendix I.
    The uprate program included a reanalysis or evaluation of all other 
aspects of large-break loss-of-coolant accident (LBLOCA), small-break 
loss-of-coolant accidents (SBLOCA), non-LOCA accidents, and Nuclear 
Steam Supply System (NSSS) and balance-of-plant (BOP) structures, 
systems, and components. Major NSSS components (e.g., reactor pressure 
vessel, pressurizer, reactor coolant pumps, and steam generators); BOP 
components (e.g., turbine, generator, and condensate and feedwater 
pumps); and major systems and sub-systems (e.g., safety injection, 
auxiliary feedwater, residual heat removal, electrical distribution, 
emergency diesel generators, containment cooling, and the ultimate heat 
sink) have been assessed with respect to the bounding conditions 
expected for operation at the uprated power level. Control systems 
(e.g., rod control, pressurizer pressure and level, turbine overspeed, 
steam generator level, and steam dump) have been evaluated for 
operation at uprated power conditions. Reactor trip and Engineered 
Safety Feature (ESF) actuation setpoints have been assessed and no 
needed changes were identified as a result of uprated power operations. 
The results of all of the above analyses and evaluations have yielded 
acceptable results and demonstrate that all design basis acceptance 
criteria will continue to be met during uprated power operations.
    For post-accident conditions, the existing post-accident dose rate 
maps are adequate for power uprate conditions, and variances from 
existing calculated values are insignificant. The resulting radiation 
levels were determined to be within current regulatory limits, and 
there would be no effect on the plant equipment, access to vital areas, 
or habitability of the control room envelope and the Technical Support 
Center. The licensee has determined that access to areas requiring 
post-accident occupancy will not be significantly affected by the power 
uprate.
    The calculated whole body and thyroid doses at the exclusion area 
boundary that might result from a postulated design basis LOCA were 
evaluated. All offsite doses evaluated at uprated power conditions 
remain below established regulatory limits. Therefore, the results of 
the radiological analyses remain below the 10 CFR part 100 guidelines 
and all radiological safety margins are maintained.

Non-Radiological Environmental Assessment

    The licensee reviewed the non-radiological environmental impacts of 
the power uprate based on information submitted in the Environmental 
Report, Operating License Stage, the NRC Final Environmental Statement 
(FES), and the requirements of the Environmental Protection Plan. Based 
on this review, the licensee concluded that the proposed power uprate 
has no significant effect on the non-radiological elements of concern 
and the plant will be operated in an environmentally acceptable manner 
as established by the FES. In addition, the licensee states that 
existing Federal, State, and local regulatory permits presently in 
effect accommodate the power uprate without modification.

Byron Station Effluent Analysis and Evaluation

    The Circulating Water (CW) System at Byron Station is a closed loop 
cooling system designed to dissipate waste heat from the turbine cycle 
to the atmosphere using natural draft cooling towers; one tower for 
each unit. Tower blowdown is accomplished by diverting flow from the 
circulating water system downstream of the CW pumps and upstream of the 
condenser and tower and discharging it to the Rock River.
    The increase in heat associated with the power uprate will 
primarily affect the CW system and will be approximately 5 percent 
higher than the heat at the present power level. This will result in a 
1  deg.F CW temperature increase. The current CW temperature rise is 
approximately 22  deg.F at 100 percent power. Although the National 
Pollutant Discharge Elimination System (NPDES) Permit does not specify 
a maximum cooling tower blowdown temperature, it controls temperature 
at the edge of the mixing zone in the river.

[[Page 1160]]

It has been determined that under a worst-case scenario, the tower 
blowdown temperature would be approximately 120  deg.F and has set this 
value as the administrative limit. Assuming a nominal summer river 
supply temperature of 70  deg.F-90  deg.F and a cooling tower blowdown 
temperature of 96  deg.F, the proposed power uprate will not impact the 
120  deg.F administrative limit.

Braidwood Station Effluent Analysis and Evaluation

    The CW system at Braidwood Station is a closed loop cooling system 
similar to that at the Byron Station, except that waste heat is 
rejected from the turbine cycle to a cooling lake. Three CW pumps per 
unit pump cooling water from the lake to the main condenser. Discharge 
from the condenser is returned to the lake, where it is separated from 
the intake supply by a dike. The heat duty increase associated with 
power uprate is mainly associated with the CW System and will be 
approximately 5 percent higher than at the present power level. This 
will result in a 1  deg.F increase to the CW temperature rise, which is 
now approximately 21.8  deg.F at 100 percent power. The increase will 
nominally increase the lake temperature as the lake temperature is 
primarily influenced by climatic conditions.
    Byron and Braidwood operate in compliance with a NPDES Permit, 
which requires all effluents to be closely monitored to assure 
compliance with the permit levels. There is no significant change in 
the types or a significant increase in the amounts of non-radiological 
effluents that may be released offsite due to the power uprate of each 
of the units at Byron Station, Units 1 and 2, and Braidwood Station, 
Units 1 and 2.

Noise Evaluation

    The noise effects due to operation of Byron Station and Braidwood 
Station at uprated power conditions were reviewed. No increase in noise 
from the turbine or reactor building will result due to uprated power 
operations. In addition, the turbine and the reactor building supply 
and exhaust fans will continue to operate at current speeds, and the 
associated noise levels will also be unaffected by uprated power 
operations. In summary, the overall noise levels at Byron Station and 
Braidwood Station will not increase due to the power uprate.
    The non-radiological environmental impacts related to the proposed 
power uprate at Byron Station and Braidwood Station have been reviewed 
and there are no adverse impacts or significant changes required to the 
current NPDES Permits or other plant administrative limits. No changes 
to land use would result and the proposed action does not involve any 
historic sites. Therefore, no new or different types of non-
radiological environmental impacts are expected.

Summary

    The proposed action will not significantly increase the probability 
or consequences of accidents, no changes are being made in the types of 
any effluents that may be released off site, and there is no 
significant increase in occupational or public radiation exposure. 
Therefore, there are no significant radiological environmental impacts 
associated with the proposed action. With regard to potential 
nonradiological impacts, the proposed action does not involve any 
historic sites. It does not affect nonradiological plant effluents and 
has no other environmental impact. Therefore, there are no significant 
nonradiological environmental impacts associated with the proposed 
action. Accordingly, the NRC concludes that there are no significant 
environmental impacts associated with the proposed action.

Alternatives to the Proposed Action

    As an alternative to the proposed action, the staff considered 
denial of the proposed action (i.e., the ``no-action'' alternative). 
Denial of the application would result in no change in current 
environmental impacts, but would reduce the operational flexibility 
that would be afforded by the proposed change. The environmental 
impacts of the proposed action and the alternative action are similar.

Alternative Use of Resources

    This action does not involve the use of any resources not 
previously considered in the Final Environmental Statement for the 
Byron Station, Units 1 and 2, and in the Final Environmental Statement 
for Braidwood Station, Units 1 and 2.

Agencies and Persons Consulted

    In accordance with its stated policy, on December 18, 2000, the 
staff consulted with the Illinois State official, Frank Niziolek of the 
Illinois Department of Nuclear Safety, regarding the environmental 
impact of the proposed action. The State official had no comments.

Finding of No Significant Impact

    On the basis of the environmental assessment, the NRC concludes 
that the proposed action will not have a significant effect on the 
quality of the human environment. Accordingly, the NRC has determined 
not to prepare an environmental impact statement for the proposed 
action.
    For further details with respect to the proposed action, see the 
licensee's letter dated July 5, 2000, as supplemented on November 27, 
2000. Documents may be examined, and/or copied for a fee, at the NRC's 
Public Document Room, located at One White Flint North, 11555 Rockville 
Pike (first floor), Rockville, Maryland. Publicly available records 
will be accessible electronically from the ADAMS Public Library 
component on the NRC Web site, http://www.nrc.gov (the Electronic 
Reading Room).

    Dated at Rockville, Maryland, this 22nd day of December 2000.

    For the Nuclear Regulatory Commission.
Anthony J. Mendiola,
Chief Section 2, Project Directorate III, Division of Licensing Project 
Management, Office of Nuclear Reactor Regulation.
[FR Doc. 01-360 Filed 1-4-01; 8:45 am]
BILLING CODE 7590-01-P