ML20245G682
| ML20245G682 | |
| Person / Time | |
|---|---|
| Site: | Limerick  |
| Issue date: | 08/08/1989 |
| From: | Butler W Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20245G677 | List: |
| References | |
| NUDOCS 8908160157 | |
| Download: ML20245G682 (5) | |
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7590-01 UNITED STATES NUCLEAR REGULATORY COMMISSION PHILADELPHIA ELECTRIC COMPANY DOCKET NO. 50-353 ENVIRONMENTAL ASSESSMENT AND FINDING OF NO SIGNIFICANT IMPACT The U. S. Nuclear Regulatory Comission (the Comission) 'is considering issuance of an exemption to Philadelphia Electric Company, (the licensee), for operation of the ' Limerick Generating Station, Unit 2, located in Montgomery and Chester Counties, Pennsylvania.
ENVIRONMENTAL ASSESSMENT Identification of Proposed Action:
The proposed exemption would extend the permitted time of operation with a non-inerted containment to accomodate completion of the Power Ascension Test Program.
The proposed action is in accordance with the licensee's application for exemption dated December 5, 1988.
Inerting the containment for the Limerick Generating Station Unit 2 is required by 10 CFR 50.44. Section50.44(c)(3)(1)statesinpartthat,
" Effective May 4, 1982 or 6 months after initial criticality, whichever is later, an inerted atmosphere shall be provided for each boiling light-water nuclear power reactor with a Mark I or Mark II type containment".
The licensee requested an exemption from 10 CFR 50.44(c)(3)(1) to extend the permitted time of operation with a non-inerted containment to accomodate completion of the Power Ascension Test Program. The Limerick Unit 2 Power 8908160157 890808 ADOCK0500g3 PDR P
. Ascension Test Program is based on maintaining the containment in a non-inerted condition until the successful completion of the 100-hour warranty run, a condition which normally would be expected to occur within approximately 120 effective full power days (EFPD) of core burn-up.
The Need for the Proposed Action:
The regulation established a six-month exemption period after initial criticality when inerting is not required with the understanding and expectation that a Power Ascension Test Program would be a continuous program unimpeded by physical or regulatory limits to power increases.
In the case of Limerick Unit 1, and most other recent BWR initial startups, unanticipated equipment problems have caused the power ascension test period to be extended" beyond the six month duration. The average actual duration is approximately ten months.
It has been a long established practice, as reflected in 10 CFR 50.44, to operate boiling water plants during power ascension testing with non-inerted containments. The high frequency of containment entries during this period of plant operations make it impractical to operate with an inerted containment and inerting would impact the effectiveness of the Power Ascension Test Program.
It is advantageous to operate the reactor without inerting the containment during the Power Ascens.fon Test program to permit inspections for identification of possible safety problems. Strict compliance with the regulation would result in undue hardships and schedule pressures in excess of those contemplated when the regulation was adopted and also in excess of recent industry power ascension testing experience.
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, Environmental Impact of the Proposed Action:
The proposed exemption from 10 CFR 50.44(c)(3)(i) will not increase the probability of'any accident or create the possibility of a new or different kind of accident from any accident previously evaluated since no changes are being made in plant operation or equipment. BWR containments are inerted with nitrogen during normal plant operation to reduce the potential for a hydrogen-oxygen reaction in the unlikely event of an accident that could generate hydrogen. However, during initial startup operations, overall plant safety is enhanced by not inerting the containment. The non-inerted containment permits frequent and prompt entries to the containment to examine equipment performance. An inerted containment will tend to inhibit these.
containment entries and thus potentially delay discovery of malfunctioning equipment.
The staff has assessed the potential environmental impacts related to operation with the additional effective full power days of core operation with a deinerted containment and has concluded that there would be no discernible incremental environmental effects. The proposed exemption will not result in any changes to the potential types of liquid, gaseous or solid effluents that might be released during operation with a
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i deinerted versus inerted containment. There is no projected difference in occupational radiation exposure with or without the exemption and no projected increases in radioactivity that might be released to the environment.
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. The staff has also concluded that there will be no significant differential in environmental impacts as a result of postulated abnormal events for the few additional months of testing without an inerted containment and the likelihood.
of accident releases to the environment is diminished by operation with a non-inerted contav. ment during the initial startup testing operations.
Accordingly, the Comission concludes that this proposed action would result in no significant radiological impact. Additionally, it does not affect non-radiological plant effluents and has no other environmental impact.
Therefore, the Commission concludes that there are no significant non-radiological environmental impacts associated with the proposed exemption.
Alternatives to the Proposed Action:
Since the Commission concluded that there are no significant environmental effects that would result from the proposed action, any alternatives with equal or greater environmental impacts need not be evaluated.
The principal alternative would be to deny the requested exemption.
This would not reduce the environmental impacts,of the plant operations and would result in reduced operational flexibility.
Alternative Use of Resources:
These actions do not involve the use of any resources not previously considered in the Final Environmental Statement for the Limerick Generating l
Station, Unit 2, dated April 1984 Agencies and Persons Consulted:
The NRC staff reviewed the licensee's request and did not consult other agencies or persons.
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. - FINDING OF NO SIGNIFICANT IMPACT The Commission has determined not to prepare an environmental impact statement for the proposed exemption.
Based upon the foregoing environmental assessment, we conclude that the proposed exemption will not have a significant effect on the quality of the human environment.
For further details with respect to this action, see the application for exemption dated December 5, 1988 which is available for public inspection at the Commission's Public Document Room, 2120 L Street, N.W., Washington, D.C.
and at the Pottstown Public Library, 500 High Street, Pottstown, Pennsylvania 19464.
Dated at Rockville, Maryland, this 8th day of August 1989.
FOR THE NUCLEAR REGULATORY COMMISSION Walter Butler, Director Project Directorate I-2 Division of Reactor Projects I/II Office of Nuclear Reactor Regulation i
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