ML19345D678
| ML19345D678 | |
| Person / Time | |
|---|---|
| Site: | Brunswick  |
| Issue date: | 12/10/1980 |
| From: | Utley E CAROLINA POWER & LIGHT CO. |
| To: | Ippolito T Office of Nuclear Reactor Regulation |
| References | |
| IEB-79-01B, IEB-79-1B, NO-80-1839, NUDOCS 8012160460 | |
| Download: ML19345D678 (2) | |
Text
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)_f December 10, 1980 Filei NG-3514(B)
SERIAL NO.: NO-80-1839 Office of Nuclear Reactor Regulation ATTENTION:
Mr. T. A.
Ippolito, Chiet Operating Reactors Branch bo 2 United States Nuclear Regulatory Commission Washington, D. C.
20555 BRUNSWICK STEAM ELECTRIC PLANT UNIT NOS. 1 AND 2 DOCKET NOS. 50-325 AND 50-324 LICENSE N05. DPR-71 AND DPR-62 EFFECT OF SPILLAGE ON ECCS PERFORMANCE
Dear Mr. Ippolito:
Your April 25, 1980 letter requested information concerning the effects on ECCS performance of a DC power supply failure and of the loss of equipment due to water spillage. For our Brunswick Steam Electric Plant (BSEP) Unit Nos. 1 and 2, Carolini. Power & Light Company (CP&L) responded to the question of DC power supply failure in a September 11, 1980 letter. This letter provides the requested infor-mation regarding the effect of water spillage.
Redundant safety-related equipment within primary containment is designed and installed in two divisions with physical separation existing between the divisions. The recirculation loop discharge and suction piping is also arranged such that spillage resulting from a recirculation loop line break would spill cnly on equipment in one of the divisions without affecting equipment in the other division.
In the design of the BSEP pressure suppression containment (i.e., drywell-torus), flooding is not considered to be a credible accident environment due to the high volume, low hydraulic resistance flow paths from the drywell to the torus which would immediately direct LOCA blowdown flow or spillage away from the drywell. Therefore, flooding as a result of spillage is not considered.
Safety-related equipment within primary containment which is in the path of spillage from a recirculation loop line break has equip-ment enclosures designed to protect the equipment from the effects of this spillage. A recent inspection of this equipment was performed in both Unit 1 and Unit 2 primary containments which verified that the f
equipment enclosure cover gaskets, covers, and hold down screws were 00i in place.
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In addition, IE Bulletin 79-OlB has required substantial studies addressing the qualification of this Class 1E equipment. A portion of this bulletin addresses the ability of Class lE equipment within primary containment to withstand a postulated harsh environment after a LOCA. This environment includes spray and humidity, which could be considered a harsher environment than spillage, although flooding level is also appropriately addressed.
Considering the above, we have concluded that a loss of primary containment safety-related equipment due to water spillage, following a recirculation loop discharge or suction line break will not add to, or change, the previously supplied equipment listing of l
the effect of a DC power supply failure on ECCS performance.
Yours very truly,
,(b Is E
E. Utley Executive Vice President Power Supply and Engineering & Construction RMP/DEM/jc (573-219) l l
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