[Federal Register Volume 61, Number 65 (Wednesday, April 3, 1996)]
[Notices]
[Pages 14837-14839]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-8298]



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NUCLEAR REGULATORY COMMISSION
[Docket Nos. 50-373 and 50-374]


Commonwealth Edison Company; Lasalle County Station, Units 1 and 
2 Environmental Assessment and Finding of No Significant Impact

    The U.S. Nuclear Regulatory Commission (the Commission) is 
considering issuance of an exemption from the requirements of Appendix 
J to 10 CFR Part 50 for Facility Operating License Nos. NPF-11 and NPF-
18, issued to Commonwealth Edison Company (ComEd, the licensee), for

[[Page 14838]]
operation of the LaSalle County Station, Units 1 and 2, located in 
LaSalle County, Illinois.

Environmental Assessment

Identification of Proposed Action

    Section III.A.5(b) of Appendix J to 10 CFR Part 50 contains 
acceptance criteria for the maximum allowable measured leakage rates 
from a plant's primary reactor containment structure for Type A leakage 
tests at both a reduced pressure and at a peak pressure.
    Section III.C.3 of 10 CFR Part 50, Appendix J, contains acceptance 
criteria for the combined leakage rate for: (1) all primary reactor 
containment penetrations as defined in Section II.G which are subject 
to Type B tests; and (2) all containment isolation valves as defined in 
Section II.H which are subject to Type C tests.
    The exemption request will replace a portion of a prior exemption 
granted in NUREG-0519, ``Safety Evaluation Report Related to the 
Operation of LaSalle County Station Units 1 and 2,'' (SER) dated March 
1981, as modified by Supplement No. 6 to that SER, dated November 1983. 
The exemption request will raise the maximum allowable TS value of the 
main steamline isolation valve (MSIV) leakage rate through all four of 
the main steamlines to 400 standard cubic feet per hour (scfh) from the 
present value of 100 scfh. This exemption request was submitted by 
ComEd in its letter dated August 28, 1995, in conjunction with its 
request for license amendments for Units 1 and 2. These amendment 
requests propose to delete the present MSIV leakage control system 
(LCS) and replace this system with an alternate leakage treatment (ALT) 
path for leakage past the MSIVs in the event of a design basis accident 
loss-of-coolant (DBA-LOCA).

The Need for the Proposed Action

    The proposed exemption would allow the licensee to continue to 
perform the Type A, B and C tests in the same manner required by 10 CFR 
Part 50, Appendix J, without penalizing the performance of these 
primary reactor containment leakage tests by including the proposed 
increase in the TS allowable leakage past the MSIVs. Specifically, the 
exemption granted in NUREG-0519 and its supplement cited above, 
excluded the MSIV leakage from the Type A, B and C tests and the 
present exemption will also continue to do so but at a higher allowable 
MSIV leakage rate.

Environmental Impacts of the Proposed Action

    The radiological consequences of a potential release of fission 
products through the ALT path would be still subject to the radiation 
exposure guidelines at the site boundary as contained in 10 CFR Part 
100 and also subject to the control room dose guidelines in General 
Design Criteria (GDC) 19 of Appendix A to 10 CFR Part 50. In addition, 
the licensee has demonstrated that the ALT path would remain 
structurally sound in the event of the design basis earthquake. 
Accordingly, granting of the requested exemption will still satisfy the 
requirement of limiting radiation exposures to acceptable limits in the 
event of a DBA-LOCA.
    Specifically, both the MSIV leakage and the primary containment 
leakage, is used to calculate the maximum radiological consequences of 
a postulated DBA-LOCA as shown in Table 15.2 of NUREG-0519. (Table 15.1 
of Supplement No. 6 to NUREG-0519 replaced this earlier table.) 
Conservative assumptions were used in the staff's reevaluation of the 
offsite and control room doses, including the doses due to the 
increased TS allowable MSIV leakage, which could result from a 
postulated DBA-LOCA. The staff's analyses demonstrate that the proposed 
leakage rate of 400 scfh past all the MSIVs results in potential dose 
exposures to the public which remain within the guideline exposure 
limits in 10 CFR Part 100. These analyses also demonstrate that the 
potential doses to the control room personnel meet the requirements in 
GDC 19 of Appendix A to 10 CFR Part 50.
    With respect to the proposed deletion of the MSIV-LCS, this action 
will reduce the overall occupational radiation dose exposures and 
reduce the generation of low level radioactive waste due to the 
elimination of maintenance and surveillance activities associated with 
the present LCS. The dose exposure associated with deleting the LCS 
will satisfy the as low as reasonably achievable (ALARA) requirements 
in 10 CFR Part 20 and will be less than the radiation doses which would 
result from maintenance and surveillance activities associated with the 
present leakage control system if it were continued to be used for the 
remainder of the station's life. Accordingly, the potential releases 
will not differ significantly from those determined previously, and the 
proposed amendments do not otherwise affect facility radiological 
effluent or occupational exposures.
    Therefore, there will not be a significant increase in the types 
and amounts of any effluent that may be released offsite and, as such, 
the proposed amendments do not alter any initial conditions assumed for 
the DBAs previously evaluated. Finally, the proposed ALT path is 
capable of mitigating the radiological consequences of these postulated 
DBAs.
    Furthermore, the proposed exemption will not result in a 
significant increase to the LOCA doses previously evaluated against the 
offsite dose guideline values contained in 10 CFR Part 100 and in the 
limits in GDC 19 of Appendix A to 10 CFR Part 50.
    With regard to potential nonradiological impacts, the proposed 
actions involve features located entirely within the restricted area as 
defined in 10 CFR Part 20. They do not affect nonradiological plant 
effluents and have no other environmental impact. Accordingly, the 
Commission concludes that there are no significant nonradiological 
impacts associated with the proposed actions.
    The Commission concludes that: (1) the proposed actions will not 
increase the probability or consequences of accidents; (2) no changes 
are being made in the types of effluents which may be released offsite; 
and (3) there is no significant increase in the allowable individual 
cumulative occupational radiation exposure nor in radiation exposure of 
the public.

Alternatives to the Proposed Action

    Since the Commission has concluded there is no measurable 
environmental impact associated with the proposed actions, any 
alternatives with equal or greater environmental impact need not be 
evaluated. As an alternative to the proposed actions, the Commission 
considered denial of the proposed actions. Denial of the application 
would result in no change in current environmental impacts.

Alternative Use of Resources

    This action does not involve the use of any resources not 
previously considered in the Final Environmental Statement for the 
LaSalle County Station dated November 1978.
    Accordingly, the impacts of the proposed action and the alterative 
action are similar.

Agencies and Persons Consulted

    In accordance with its stated policy, on February 21, 1996, the NRC 
staff consulted with the Illinois State Official, Mr. Frank Niziolek, 
Head, Reactor Safety Section, Division of Engineering, Illinois 
Department of

[[Page 14839]]
Nuclear Safety; regarding the environmental impact of the proposed 
action. The State official had no comments.

Finding of No Significant Impact

    Based upon the environmental assessment, the Commission concludes 
that the proposed action will not have a significant effect on the 
quality of the human environment. Accordingly, the Commission has 
determined not to prepare an environmental impact statement for the 
proposed exemption.
    For further details with respect to the proposed action, see the 
request for exemption dated August 28, 1995, which is available for 
public inspection at the Commission's Public Document Room, The Gelman 
Building, 2120 L Street, NW., Washington, DC, and at the local public 
document room, located at the Jacobs Memorial Library, Illinois Valley 
Community College, Oglesby, Illinois 61348.

    Dated at Rockville, Maryland, this 26th day of March 1996.

    For the Nuclear Regulatory Commission
Robert A. Capra,
Project Director, Project Directorate III-2, Division of Reactor 
Projects III/IV, Office of Nuclear Reactor Regulation.
[FR Doc. 96-8298 Filed 4-2-96;8:45am]
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