ML20211D877
| ML20211D877 | |
| Person / Time | |
|---|---|
| Site: | Summer  |
| Issue date: | 09/17/1997 |
| From: | NRC (Affiliation Not Assigned) |
| To: | |
| Shared Package | |
| ML20211D873 | List: |
| References | |
| NUDOCS 9709290273 | |
| Download: ML20211D877 (3) | |
Text
_-____.
UNITED STATES j
, "g NUCLEAR' REGULATORY COMMISSION p
WASHINGTON, D.C. 800eH001
...p SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT NO.138TO FACILITY OPERATING LICENSE NO, NPF-12 SOUTH CAROLINA ELECTRIC & GAS COMPANY SOUTH CAROLINA PUBLIC SERVICE AUTHORITY VIRGIL C. SUMMER NUCLEAR STATION. UNIT NO 1 DOCKET NO. 50-395
1.0 INTRODUCTION
By application dated March 26,1997, South Carolina Electric & Gas Company (SCE&G) (the licensee) requested changes to the Technical Specifications (TS) for the Virgil C. Summer Nuclear Station (VC5NS). The proposed changes would change the Technical Specifications (TS) definition of Core Alteration. At present, the TS definition includes " movement or manipulation of any component within the reactor vessel" as Core Alterations. The licensee proposes to revise the current definition such that a Core Alteration would be limited to movement of any fuel, source, or reactivity control component.
2,0 BACKGROUND The VCSNS TS define Core Alteration as follows: " Core Alteration shall be the movement or manipulation of any component within the reactor vessel with the vessel head removed and fuelin the vessel." The VCSNS TS require and will continue to require that containment
- integrity be established during Core Alterations. A literal interpretation of the TS definition results in containment integrity being required when conducting activities ranging from removal of the reactor vessel upper intemals to placing lights or a TV camera in the reactor vessel. A literal interpretation thus results in more complex and correspondingly longer outages. To eliminate this problem without impacting on safety, the licensee proposes to adopt the definition of Core Alteration from NUREG-1431, " Standard Technical Specifications Westinghouse Plants." This definition states that " Core Alteration shall be the movement of any fuel, sources, or reactivity control components with the vessel head removed and fuel in the vessel." The proposed definition only addresses activities that impact on reactivity, and excludes movement of any other components in the reactor vessel. The staff has reviewed the licensee's proposal. The results of the staff review are discussed below.
3.0 EVALUATION As discussed above, the focus of this TS change is to reduce the requirement for containment integrity by reducing the applicability of Core Alterations. The purpose of -
requiring containment integrity is to preclude the release of radioactivity into the environment.
Such releases could be the result of 1) accidents such as dropping an irradiated fuel assembly (fuel handling accident) or dropping heavy loads on irradiated fuel in the reactor vessel, and 2) reactivity excursions within the reactor vessel. This evaluation addresses the on nQb 9709290273 970917 PDR ADOCK 05000395 P
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- effect of the proposed definition change with respect to potential accidents. The proposed new definition does not impact on TS requirements associated with potential reactivity excursions.
At VCSNS, the heavy loads of concem are the reactor vessel upper intemals. The current TS definition of Core Alteration includes handling of the upper intemals. The proposed new definition, however, would not be applicat:'e to this activity. In tum, the requirement to establish containment integrity during movement d the upper intamals would also not be applicable. Heavy load handling at VCSNS is conducted in accordance with the guidance of NUREG-0612, " Control of Heavy Loads at Nuclear Power Plants." By GL 85-11, dated 6/28/85, the staff concluded that implementation of the guidelines of NUREG-0612 provided sufficient protection such that the risk associated with heavy load drops is acceptably small.
Based on this, the staff concludes that the proposed change to the definition of Core Alteration is acceptable with respect to moving the reactor vessel upper intamals.
The proposed new definition would also not be applicable to movement of any other components in the reactor vessel with fuel in the vessel. At VCSNS, all movement of components within the reactor veseel that is not associated with the vessel intemals or with reactivity control components is bounded by the fuel handling accident. At VCSNS, the fuel handling accident assumes an irradiated fuel assembly is dropped into the reactor core. The analysis shows that all damage is confined to the fuel assembly that was dropped. There is no damage to irradiated fuel in the core.- All components that may be moved within the reactor vessel at VCSNS (other than as described above) weigh less than a fuel assembly (e.g., small tools, TV camera, lights, etc.). Therefore, dropping one of these components would not result in fuel damage or the possibility of a release of radioactivity. The staff, therefore, concludes that movement of such components without establishing containment -
integrity is acceptable.
The existing definition of Core Alteration addresses " movement or manipulation" of components. The proposed definition deletes the phrase "or manipulation." The terms
" movement" and " manipulation" have the same meaning with respect to the definition of Core.
Alteration. Deleting the latter phrase removes one of two redundant terms along with any potential contusion, but there is no change in TS applicability and no impact on safety. The staff, therefore, concludes that this proposed change is also acceptable.
The current TS definition of Core Afteration also includes the following: " Suspension of Core Alterations shall not preciude completion of movement of a component to a safe conservative position." This statement is included in the proposed definition except that the word
" conservative" is deleted, it is the staff's view that " safe" and " conservative" have the same meaning in the context of this definition, and deleting " conservative" will have no safety impact. Based on its review of the licensee's submittal and on information provided by the licensee, the staff concludes that changing the VCSNS current definition of Core Alteration to reflect the definition in NUREG-1431 will not have an adverse impact on safety and is, therefore, acceptable.
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4.0 STATE CONSULTATION
la accordance with the Commission's regulations, the State of South Carolina official was
- mtified of the proposed issuance of the amendment. The State official had no comments.
5.0 ENVIRONMENTAL CONSIDERATION
The amendment changes a requirement with respect to installation or use of a facility component located within the restricted area as defined in 10 CFR Part 20. The NRC staff has determined that the amendment involves no significant increase in the amounts, and no significant change in the types, of any affluents that may be released offsite, and that there is no significant increase in individual or cumulative occupational radiation exposure. The Commission has previously issued a proposed finding that the amendment involves no significant hazards consideration, and there has been no public comment on such finding (62 FR 27800). Accordingly, the amendment meets the eligibility criteria for categorical axclusion set forth in 10 CFR 51.22(c)(g). Pursuant to 10 CFR 51.22(b) no environmental impact
. statement or environmental assessment need be prepared in connection with the issuance of the amendment.
6.0 CONCLUSION
The Commission has concluded, based on the considerations discussed above, that (1) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, (2) such activities will be conducted in compliance with
- the Commission's regulations, and (3) the issuance of the amendment will not be inimical to the common defense and security or to the health and safety of the public.
Principal Contributors: Edward Tomlinson A. Attard Date: September 17. 1997 l