ML20205G698
| ML20205G698 | |
| Person / Time | |
|---|---|
| Site: | Summer  |
| Issue date: | 08/12/1986 |
| From: | Rubenstein L Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20205G702 | List: |
| References | |
| NUDOCS 8608190594 | |
| Download: ML20205G698 (4) | |
Text
f 7590-01 UNITED STATES NUCLEAR REGULATORY COMMISSION SOUTH CAROLINA ELECTRIC & GAS COMPANY SOUTH CAROLINA PUBLIC SERVICE AUTHORITY VIRGIL C. SUMMER NUCLEAR STATION,' UNIT 1 DOCKET NO. 50-395 NOTICE OF ENVIRONMENTAL ASSESSMENT AND FINDING OF NO SIGNIFICANT IMPACT The United States Nuclear Regulatory Commission (the Commission) is
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considering issuance of an amendment to Facility Operating License No. NPF-12, i
issued to South Carolina Electric & Gas Company and South Carolina Public Service Authority (the licensees), for operation of the Virgil C. Summer Nuclear Station, Unit 1, located in Fairfield County, South Carolina.
ENVIRONMENTAL ASSESSMENT Identification of Proposed Action:
The amendment would revise Technical Specification 3/4.4.5, " Steam Generators" and its bases to allow for the repair of steam generator tubes.
The licensee's application for amendment was dated January 16, 1986 as supplemented March 18, May 8. and July 22, 1986.
The Need for the Proposed Action:
During the last refueling outage, pure water stress corrosion cracking (PWSCC)wasobservedinsomesteamgeneratortubesandapproximately170 tubes were plugged as a result.
8608190594 860812 PDR ADOCK 05000395 P
The licensee has pursued an aggressive program to limit the effects of PWSCC. During the last refueling outage, the Westinghouse rotopeening process was applied in the steam generator hot legs.
Because of tooling problems, this process was only applied in the central region of the tube sheet. Current plans are to shotpeen the remaining peripheral region during the next refueling outage, if an acceptable process is available.
In the interim,.it is expected that some cracking may occur in this unpeened region.
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Steam generator tube repair is needed to recover some tubes (approximately
- 71) previously plugged, and to keep from plugging new tubes with indications greater than 40% through the tube wall.
The plugging of steam generator tubes is undesirable because it reduces reactor coolant system flow, increases moisture carry-over in the steam lines, and shortens component life. The application of tube repair processes (e.g.,
by sleeving, brazing or partial tube replacement) allows the tubes to remain in service, thereby reducing, if not negating, the above mentioned effects.
In addition, tube repair capability would allow the plant to maintain margin with respect to the limits assumed in the safety analysis.
Environmental Impacts of the Proposed Action:
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The proposed amendment regarding steam generator tube repair would allow imperfect tubes to be returned to their original integrity. Accordingly, i
accident radiological releases will not be greater than previously determined.
l Tube repair produces occupational radiation doses and solid raoioactive wastes approximately in the same amount as that incurred by tube plugging.
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the 71 tubes currently plugged that could be unplugged and have tube repair l
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performed, the estimated occupational radiation exposure to unplug and repair the tubes is 12.43 REM, which is less than 1% of the estimated annual occupational radiation exposure contained in the Final Environmental Statement, dated May 1981.
3 It is estimated that approximately 125 ft of solid radioactive waste would be created from unplugging and repairing these 71 tubes. This is less than 2.5% of the estimate for solid radioactive waste shipped annually contained in the Final Environmental Statement.
From the above evaluation of accidents, occupational radiation exposure, and radiological effluents, the Connission concludes that there are no significant radiological environmental impacts associated with granting of the proposed amendment.
With regard to potential non-radiological impacts, the proposed amendment involves systems located entirely within the restricted area as defined in 10 CFR Part 20.
It does not affect non-radiological plant effluents and has no other environmental impact. Therefore, the Comission concludes that there are no significant non-radiological environmental impacts associated with the proposed amendment.
Alternatives to the Proposed Action:
Since the Commission has concluded that the environmental effects of the proposed action are not significant, any alternatives with equal or greater environmental impacts need not be evaluated.
The principal alternative would be to deny the requested amendment. This would not reduce the environmental impacts associated with correction of steam generator tube imperfections and wculd result in reduced reactor coolant system flow, potentially leading to derating of the plant.
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. Alternative Use of Resources:
This action does not involve the use of any resources not previously considered in the "Ffpal Envirtwental Statement Related to the Operation of Virgil C. Summer Nuclear Station, Unit 1" (NUREG-0719), dated May 1981.
Agencies and Persons Consulted:
The NRC staff reviewed the licensee's Nguest and did not consult other agencies or persons.
FINDING OF NO SIGNIFICANT IMPACT
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The Connission has detemined not to prepare an environmental impact statement for the proposed afnendment. Based upon the foregoing environmental assessment, the NRC staff concludes that the proposed action will not have a significant effect on the quality of the human environment.
For further details with respect to this actiori, see the request for amendment dated January 16, 1986, as supplemented March 18, May 8, and July 22, 1986, which is available for public inspection at the Ccmmission's Public Document Room,1717 H Street, N.W., Washington, D.C., and at the fairfield County Library, Garden and Washington Streets, Winnsboro, South Carolina 29810.
Dated at Bethesda, Maryland this 12th day of Au gd s t, 1986.
FOR THE NUCLEAR REGULATORY COMMISSION ISgLtb Lester S. Rubenstein, Director PWR Proiect Directorate #2 Division of PWR Licensing-A Office of Nuclear Reactor Regulation A