United States Nuclear Regulatory Commission - Protecting People and the Environment

Implementation of TMI Action ITEM II.K.3.5, "Automatic Trip of Reactor Coolant Pumps" (Generic Letter No. 86-05)


                               UNITED STATES 
                       NUCLEAR REGULATORY COMMISSION 
                          WASHINGTON, D. C. 20555 

                                May 29, 1986

TO ALL APPLICANTS AND LICENSEES WITH BABCOCK AND WILCOX (B&W) DESIGNED 
NUCLEAR STEAM SUPPLY SYSTEMS (NSSSs) 

SUBJECT:  IMPLEMENTATION OF TMI ACTION ITEM II.K.3.5, "AUTOMATIC TRIP OF 
          REACTOR COOLANT PUMPS" (GENERIC LETTER NO. 86-05) 

Gentlemen: 

The purpose of this letter is to inform you of (1) the staff's conclusions 
regarding the B&W Owners Group (BWOG) submittals on reactor coolant pump 
trip in response to Generic Letters 83-10e and f, and (2) provide guidance 
concerning implementation of the reactor coolant pump trip criterion. Our 
Safety Evaluation (SE) on this subject is enclosed for your use. 

With regard to the BWOG submittals referenced in Section V of the enclosed 
SE, we conclude that the methods employed by the BWOG to justify manual 
reactor coolant pump (RCP) trip are consistent with the guidelines and 
criteria provided in Generic Letters 83-10e and f. The approved B&W Small 
Break LOCA Evaluation Model was used to demonstrate compliance with 10 CFR 
50.46 and Appendix K to 10 CFR Part 50. 

We have determined that the information provided by the BWOG in support of 
the loss-of-subcooling RCP trip criterion is acceptable. The generic 
information presented by the BWOG, however, does not address plant specific 
concerns about instrumentation uncertainties, potential reactor coolant pump
problems and operator training and procedures as requested in Generic Letter
83-10. This information, contained in Section IV of the SE, is now being 
requested to assess implementation of the RCP trip criterion. 

Accordingly, for those applicants and licensees who choose to endorse the 
BWOG methodology, we request that operating reactor licensees implement the 
RCP trip criterion based upon the BWOG methodology. Schedules for submittal 
of information requested in Section IV of the SE (refer to Appendix A for 
considerations associated with Generic Letters 83-10e and f) should be 
developed with your individual project managers within 45 days from receipt 
of this letter. The requested information does not constitute a new 
requirement but only identifies information specified in Generic Letters 
83-10e and f which has not been provided under the BWOG generic program. In 
@ the event that licensees decide not to trip the RCP (an option provided 
for in Generic Letters 83-10e and f), they should respond to the questions 
in Section IV of the SE and refer to Appendix B of the SE. Applicants should
provide toe appropriate response to the extent that this information is 
known at this time. 

Those applicants and licensees who choose not to endorse the BWOG 
methodology should submit a schedule for submittal of plant specific RCP 
trip criteria or justification for non-trip of RCPs within 45 days of 
receipt of this letter. 

                                    - 2 -

This request for information was approved by the Office of Management and 
Budget under clearance number 3150-0011 which expires September 30, 1986. 
Comments on burden and duplication may be directed to the Office of 
Management and Budget, Reports Management, Room 3208, New Executive Office 
Building, Washington, D.C. 20503. 

Our review of your submittal of information in response to this letter is 
not subject to fees under the provisions of 10 CFR 170. However, should you, 
as part of your response or in a subsequent submittal, include an 
application for license amendment or other action requiring NRC approval, it 
is subject to the fee requirements of 10 CFR 170 with remittal of an 
application fee of $150 per application (Sections 170.12(c) and 170.21) and 
subsequent semiannual payments until the review is completed or the ceiling 
in Section 170.21 is reached. 

If you believe further clarification regarding this issue is necessary or 
desirable, please contact Mr. R. Lobel (301 492-9475). 

                              Sincerely, 


                              Frank J. Miraglia, Director 
                              Division of PWR Licensing-B 

Enclosure: 
Safety Evaluation 

cc w/enclosure: 
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