ML19331D865

Describes Interim Actions Needed Prior to Issuance of OL to Further Reduce Risk from ATWS Before Required Plant Mods,As Determined by Commission,Are Completed.Atws Emergency Operating Procedure Should Be Submitted

ML19331D865
Person / Time
Site:	Callaway
Issue date:	08/15/1980
From:	Tedesco R Office of Nuclear Reactor Regulation
To:	Bryan J UNION ELECTRIC CO.
References
NUDOCS 8009030672
Download: ML19331D865 (2)

Text

{{#Wiki_filter:. ?~ hp UNITED STATES S. j.1.;p 'g NUCLEAR REGULATORY COMMISSION wAsmoroN. o. c. :osss g]g , j g .~j AUG 1 - 1333 Docket Nos.: 50-483 and 50-486 Union Electric Company ATTN: Mr. John K. Bryan Vice President - Nuclear P. O. Box 149 St. Louis, Missouri 63166

SUBJECT:

INTERIM ACTICNS NEEDED FOR PLANT OPERATION PENDING FINAL RESOLUTION OF ANTICIPATED TRANSIENTS WITH FAILURE TO SCRAM (ATWS) (WESTINGHOUSE PWR) In December 1978 the Nuclear Regulatory Commission (NRC) staff issued Volume 3 of NUREG-0460 which describes the proposed type of plant modifications the staff believes are necessary to reduce the risk from anticipated transients with failure to scram (ATWS) to an acceptable level. The NRC's Regulatory Requirements Review Comittee completed its review in January 1979, and concurred with the staff's approach described in Volume 3 of NUREG-0460, insofar as it applies to your plant. The staff has issued requests for the industry to supply generic analyses to confirm the ATES mitigation capability described in Volume 3 of NUREG-0460. Subsequently, the staff plans to present its recommendations for rulemaking on ATWS to the Ccmission. The Commission would, by rulemaking, determine the required modifications to resolve ATWS concerns and the required schedule for the implementation of such modifications. Your plant would, of course, be subject to the Comission's decision in this matter. Based on considerations described in pages 42 through 45, Volume 3 of NUREG-0460, the staff generally concluded that plants with operating licenses can continue to operate without undue risk to the health and safety of the public during the estimated 2 to 5 year period needed to implement the necessary modifications. However, the staff believes the following steps should be taken as a prudent course prior to the issuance of an operating license in order to further reduce the risk from ATWS events during the interim period before the required plant modifications as determined by the Comission are completed. 1. An emergency operating procedure should be developed for an ATWS event, including consideration cf scram indicators, rod position indicators, flux monitm, pressurizer level and pressure indicators, pressurizer relief valve and safety valve position indicators, coolant average temperature, containment temperature and pressure indicators, steam generator level, pressure and flow indicatcrs, and any other alarms 8000030 =

I 4 Mr. John K. Bryan annunciated in the control room including alarms not processed through the electrical portion of the reactor scram system. The emergency operating procedure should be sufficiently simplified and unambiguous to permit prompt ATWS recognition. 2. The emergency operating procedure should describe actions to be taken in the event of an ATWS including consideration of manually scramming the reactor by using the manual scram buttons, prompt actuation of the auxiliary feedwater system to assure ' delivery of the full capacity of this system, and initiation of turbine trip. These actions must be taken irmediately following the occurrence of the event. Actions should also include prompt initiation of boration by actuation of the high pressure safety injection system to bring the plant to a safe shutdown condition. We require that you submit your ATWS emergency operating procedure. Our review may include a visit to your plant to determine the feasibility of implementing your proposed procedures through operator simulation of the steps. Our evaluation must conclude that an acceptable procedure and operator training are completed prior to the issuance of a full power operating license. ] Sincerely, q.,C ' WW

~

Robert L. Tedesco, Assis ant Director f for Licensing Civision of Licensing cc: See next page l l l l l l t l ?

s I Mr. J. K. Bryan Vice President - Nuclear Union Electric Company P. O. Box 149 St. Louis, Missouri 63166 cc: Mr. Nicholas A. Petrick Executive Director - SNUPPS 5 Choke Cherry Road Rockville, Maryland 20850 Gerald Charnoff, Esq. Shaw, Pittran, Potts, Trowbridge & Madden 1800 M Street, N.W. Washington, D. C. 20036 Mr. J. E. Birk Assistant to the General Counsel Union Electric Company P. O. Box 149 St. Louis, Missouri 63166 Dr. Vern Starks Route 1 Box 863 Ketchikan, Alaska 99901 Ms. Treva Hearn, Assistant General Counsel Missouri Public Service Comission P. O, Box 3f,0 Jef ferson City, Missouri 65102 am Resident Inspector U. S. Nuclear Regulatory Connission P. O. Box 1743 Jefferson City, Missouri 65101 Mr. D. F. Schnell Manager - Nuclear Engineering Union Electric Company P. O. Box 143 St. Louis, Missouri 63166 =}}