NRC Generic Letter 1981-35

NRC Generic Letter 1981-035: Safety Concerns Associated with Pipe Breaks in the BWR Scram System

ML031110044
Person / Time
Issue date:	08/31/1995
From:	Eisenhut D G Office of Nuclear Reactor Regulation
To:
References
NUREG-0803 GL-81-035, NUDOCS 8112170388
Download: ML031110044 (1)

• ,UNITED STATESNUCLEAR REGULATORY COMMISSIUNWASHINGTON. D. C. 205 r* ha August 31, 1981TO ALL BWR APPLICANTS FOR CP's, HOLDERS OF CP's. AND APPLICANTS FOR OL'sGentlemen:SUBJECT: SAFETY CONCERNS ASSOCIATED WITH PIPE BREAKS IN THE BWR SCRAMSYSTEM (GENERIC LETTER 81-35)In April 1981 the NRC staff sent a letter to each BWR license applicantirequesting certain information on this subject. We indicated that thisitem must be resolved prior to issuance of an operating license. Sub-sequently, on July 7, 1981 the NRC staff sent a letter to all BWRlicensees informing them that the generic review of this issue had beencompleted. We indicated that a NUREG report describing the results ofthis review would be issued.This letter forwards NUREG-0803, "Generic Safety Evaluation ReportRegarding Integrity of BWR Scram System Piping," dated August 1981.Section 5 of NUREG-0803 presents the staff's generic conclusions on thisissue. Briefly, the staff has concluded that the SDV piping systemdesign is acceptable, provided certain conditions are satisfied on aplant specific basis. The staff further concluded that the safety-concerns associated with a postulated failure of the SDV piping systemdo not represent a dominant contribution to the risk of core melt,-provided certain assumptions used in the risk assessment are validatedon a plant specific basis.-NUREG-08Q3 provides the staff's guidance and schedule for implementa-tion. As provided in our April 1981 letter, cited above, plant specificresponses should be provided for all plants with Mark I and Mark IIcontainments to support issuance of an operating license. Plant speci-fic responses conforming to the guidance contained in NUREG-0803will satisfy the information requested in our April 1981 letter. Thisletter is being provided to applicants with Mark III containments forinformation purposes, since the staff has concluded that this is not asafety issue for the Mark III containment design.Sincerely,CADivision of icensingOffice of Nuclear Reactor RegulationEnclosure:As statedcc: Service List -58112170388 810831PDR NUREG0803 C PDR:, 6I