REVIEW RESPONSIBILITIES Primary- Accident Evaluation Branch (AEB) Secondary- None

A potential source of fission product leakage following a loss-of-coolant accident (LOCA) is the leakage past the main steam isolation valves in a BWR. This leakage is controlled by a main steam isolation valve leakage control system (MSIViJCS). This system may be a positive sealing system or a vacuum type system which collects leakage between the closed isolation valves and releases it to the atmosphere through a filter system. The AEB reviews the method of operation, time of opera-tion, and release paths associated with operation of the MSIVLCS to calculate the fission product releases and their contributions to the doses following a LOCA at the exclusion area and low population zone boundary. The AEB coordinates its evaluation with other branches that interface with the overall evaluation of the LOCA radiological consequence analysis. The Auxiliary Systems Branch (ASB) reviews the design of the MSIVLCS and essential subsystems in accordance with Regulatory Guide 1.96 (Ref. 1) as part of its primary review responsibility for SRP Section 6.7 to assure the system's ability to function following a postulated LOCA including the loss of offsite power. The Containment Systems Branch (CSB) will verify, upon request by AEB, that for a vacuum type system, the operation of the MSIVLCS does not produce an adverse pressure transient in the secondary containment. The acceptance criteria necessary for the review of these areas and their methods of application are contained in the above referenced SRP section of the corresponding primary branch. II. ACCEPTANCE CRITERIA The radiological consequences associated with the operation of the MSIVLCS following a postulated LOCA are combined, under SRP Section 15.6.5, Appendix A, Rev. 1- July 198