ML20214G466
| ML20214G466 | |
| Person / Time | |
|---|---|
| Site: | Brunswick  |
| Issue date: | 05/15/1987 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20214G455 | List: |
| References | |
| NUDOCS 8705270075 | |
| Download: ML20214G466 (3) | |
Text
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UNITED STATES y
3 c. ( [ g NUCLEAR REGULATORY COMMISSION
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SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION SUPPORTING AMENDMENT N0.107 TO FACILITY OPERATING LICENSE NO. DPR-71 CAROLINA POWER & LIGHT COMPANY BRUNSWICK STEAM ELECTRIC PLANT, UNIT 1 DOCKET NO. 50-325
1.0 INTRODUCTION
The primary means of containment post-accident purging, as well as normal s
operational purging, is through a 2-inch drywell bypass line. This bypass
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line directs the discharge around the large 18-inch purge isolation valves to the Standby Gas Treatment System (SBGTS). By letter dated December 16, e
1986, the licensee proposed to remove the inboard 2-inch isolation valve along with two test connection isolation valves from the drywell bypass line and place them in an identical isolation arrangement on the 20-inch purge line located on the suppression chamber. Additionally, the remaining 2-inch drywell bypass line with the outer isolation valve would be rerouted to tie into the 18-inch purge line between the main isolation 18-inch valves rather than prior to the inboard valve. Both of the affected penetrations are part of theContainmentAtmosphereDilution(CAD) System. The licensee also proposes to retain all controls of the moved isolation valves, as well as its contain-ment isolation signal override capability. This ova ride capability would also be extended to the 18-inch inboard drywell purge isolation valve.
The above modifications t
.ae drywell and suppression chamber purge lines have been proposed to take advantage of the radioactive scrubbing capability of the suppression pool. Without the changes, post-accident venting using the small 2-inch line would go directly from the drywell to the SBGTS. With the modifications, the pathway would be from the drywell, through the pool and then to the SBGTS.
These changes are the same as those that have been approved by the staff and implemented on Brunswick Unit 2.
The staff's evaluation concerning these changes, as well as other modifications, was issued on May 5, 1986, to support the Brunswick Unit 2 Technical Specification (TS) changes in Amendment 125.
The licensee's submittal of December 16, 1986, also included a proposed revision to the Unit 1 TSs that was necessitated by the above valving modifications.
2.0 EVALUATION The proposed purge line changes will affect the overall plant isolation arrangement to a very limited extent.
Basically, one half of the drywell 1
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2-inch bypass line will be removed and added to the suppression chamber purge line. As a result, the line arrangement from the suppression chamber will be identical to the existing drywell purge arrangement. The remaining drywell pathway will still be quite similar to the existing pathways. The only significant change is related to the isolation role of the inboard 18-incn valve.
In the modified version, the valve serves as the inboard isolation valve for both the main 18-inch pathway, as well as the 2-inch bypass. This arrangement satisfies both GDC 54 and GDC 56 of 10 CFR Part 50, Appendix A, and, therefore, is acceptable. The suppression chamber isolation arrangement, i
since it is identical to the current drywell arrangement, is also acceptable.
In addition to the above considerations, the proposed modifications have been implemented on Brunswick Unit 2.
Acceptance of these proposed modifications would allow Unit I to become identical to Unit 2 with respect to the previously i
staff approved piping arrangements.
j Finally, the proposed TS change is simply a change in the nomenclature of the moved isolation valve. Again, this change will make both Unit I and 2 TSs identical in this area.
Based on the evaluation provided above, the staff finds the proposed modifi-cations to the purge lines of the CAD System and the corresponding revision to the TS are acceptable.
3.0 ENVIRONMENTAL CONSIDERATION
S This amendment changes a requirement with respect to installation or use of a facility component located within the restricted area as defined in i
10 CFR Part 20. The staff has determined that the amendment involves no significant increase in the amounts, and no significant change in the types, of any effluents that may be released offsite; and that there should be no significant increase in individual or cumulative occupational radiation exposure. The Commission has previously issued a proposed finding that this amendment involves no significant hazards consideration, and there has been no public comment on such finding. Accordingly, this amendment meets the eligibility criteria for categorical exclusion set forth in 10 CFR 551.22(c)(9).
Pursuant to 10 CFR 551.22(b), no en-vironmental 'mpact statement or environmental assessment need be prepared i
in connection with the issuance of the amendment.
1
4.0 CONCLUSION
1 Th~ Commission made a proposed determination that the amendment involves anificant hazards consideration, which was published in the Federal r
Re1 ster on February 11,1987(52FR4403),andconsultedwiththeState of North Carolina. No public comments were received, and the State of North Carolina did not have any comments.
i We have concluded, based on the considerations discussed above, that:.(1) there is reasonable assurance that the health and safety of the public 4
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3-will not be endangered by operation in the proposed manner, and (2) such activities will be conducted in compliance with the Comission's re-gulations, and the issuance of the amendment will not be inimical to the comon defense and security or to the health and safety of the public, i
1 Principal Contributor:
J. S. Guo i
Dated: May 15, 1987 s
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