Information Notice No. 95-42: Commission Decision on the Resolution of Generic Issue 23, "Reactor Coolant Pump Seal Failure"

                                 UNITED STATES
                         NUCLEAR REGULATORY COMMISSION
                         WASHINGTON, D.C.  20555-0001

                              September 22, 1995

                               GENERIC ISSUE 23, "REACTOR COOLANT PUMP SEAL    


All holders of operating licenses or construction permits for nuclear power


The U.S. Nuclear Regulatory Commission (NRC) is issuing this information
notice to notify addressees of the Commission's decision on Generic Issue
(GI) 23, "Reactor Coolant Pump Seal Failure."  This decision was documented in
a staff requirements memorandum (SRM) from John C. Hoyle to James M. Taylor,
dated March 31, 1995 (Accession Number 9504140300), written in response to
SECY-94-225, "Issuance of Proposed Rulemaking Package on GI-23, `Reactor
Coolant Pump Seal Failure'."  No specific action or written response is
required as a result of this information notice.


On April 19, 1991, the NRC published a Federal Register notice (56 FR 16130)
requesting comments on the then-current understandings, findings, and
potential recommendations regarding GI-23, together with a draft Regulatory
Guide, DG-1008, "Reactor Coolant Pump Seals."  On May 2, 1991, NRC issued
Generic Letter (GL) 91-07, "GI-23, `Reactor Coolant Pump Seal Failures' and
Its Possible Effect on Station Blackout," which stated that preliminary
results of NRC studies suggested that reactor coolant pump (RCP) seal leak
rates could be substantially higher than those assumed in the coping analyses
for implementation of the station blackout (SBO) issue.  The generic letter
reminded licensees that higher seal leak rates could affect licensee analyses
and actions addressing conformance to the SBO rule.

Staff studies and analyses concerning RCP seal leakage are documented in
Appendices A and B to NUREG/CR-5167, "Cost/Benefit Analysis for Generic
Issue 23:  Reactor Coolant Pump Seal Failure," April 1991, which contains the
NRC model for RCP seal failure.  The report identifies several modes of RCP
seal leakage which may be in excess of that assumed in licensee coping
analyses for implementing the requirements of 10 CFR 50.63, the SBO rule.  
GI-23 is related to a number of other generic issues:  GI-65, "Component
Cooling Water System Failure"; GI-130, "Essential Service Water (ESW) System
Failure at Multiplant Sites"; GI-153, "Loss of Essential Service Water in
LWRs"; GI-106, "Piping and the Use of Highly Combustible Gases in Vital
Areas"; and Three Mile Island (TMI) Actions II.K.2.16 and II.K.3.25.  In
addition, the Individual Plant Evaluation (IPE) Program, as described in 

9509200232.                                                            IN 95-42
                                                            September 22, 1995
                                                            Page 2 of 2

GL 88-20, requests evaluation of plant vulnerabilities with respect to certain
generic issues, including GI-23.  


The Commission considered the proposed rulemaking as a method to resolve 
GI-23.  In SECY-94-225, dated August 26, 1994, a draft rule was proposed for
public comment that would resolve GI-23.  

On March 31, 1995, the Commission voted against the publication of the
proposed rule on the resolution of GI-23, "Reactor Coolant Pump Seal Failure." 
The Commission concluded that the proposed rule did not provide sufficient
gain in safety to justify its issuance.  The Commission was also concerned
that inaccuracies in the NRC seal leakage evaluation model may exist. 
Further, the wide range of plant-specific considerations with regard to
pressurized-water reactor (PWR) RCP seals would result in the spending of
excessive resources by some licensees without commensurate safety benefits;
also some licensees are addressing the issue by using the IPE program and
accident management strategies.  Therefore, the NRC will not proceed with the
rulemaking effort described in SECY-94-225.  The staff is currently exploring
options to determine what, if any, further action will be taken regarding the
final disposition of GI-23.  

This information notice requires no specific action or written response.  If
you have any questions about the information in this notice, please contact
one of the technical contacts listed below or the appropriate Office of
Nuclear Reactor Regulation (NRR) project manager. 

                                    /s/'d by DMCrutchfield

                                    Dennis M. Crutchfield, Director
                                    Division of Reactor Program Management
                                    Office of Nuclear Reactor Regulation

Technical contacts:  Chu-yu Liang, NRR              Syed K. Shaukat, RES
                     (301) 415-2878                 (301) 415-6592

                     Christopher Jackson, NRR
                     (301) 415-2947

Lead project manager:   Linh N. Tran, NRR
                        (301) 415-1361


Page Last Reviewed/Updated Wednesday, March 24, 2021