United States Nuclear Regulatory Commission - Protecting People and the Environment

Information Notice No. 83-53: Primary Containment Isolation Valve Discrepancies

                                                            SSINS No.: 6835 
                                                            IN 83-53       

                                UNITED STATES
                        NUCLEAR REGULATORY COMMISSION
                    OFFICE OF INSPECTION AND ENFORCEMENT
                           WASHINGTON, D.C. 20555
                                     
                               August 11, 1983

Information Notice No. 83-53:   PRIMARY CONTAINMENT ISOLATION VALVE 
                                   DISCREPANCIES 

Addressees: 

All boiling water reactors holding an operating license (OL) or construction
permit (CP). 

Purpose: 

This information notice is provided as a notification of discrepancies in 
the initiating signals for group 1 primary containment isolation valves. It 
is expected that recipients will review the information for applicability to
their station. No specific response is required at this time. 

Description of Circumstances: 

On January 3, 1983, at Browns Ferry Station, the site resident inspector 
reviewed technical specifications section 3.7. During the review the 
resident inspector noted that the isolation valves in the reactor water 
sample line were listed as group 1 isolation valves, and these valves 
receive a close signal from all the group 1 initiating signals. The FSAR 
also stated that all group 1 initiating signals will shut these sample 
valves. These findings appeared to conflict with the actual logic and an 
examination of the electrical diagrams indicated that the sample valves only 
close from two of the five group 1 isolation signals. Those two signals are 
low low reactor water level (level 2) and high main steam line radiation. 
This was verified to be consistent with the actual circuitry. The resident 
inspector reported the discrepancy to the Regional Office and the Office of 
Inspection and Enforcement for followup actions. 

During the summer of 1982 the technical specifications surveillance 
requirements were reviewed at Brunswick Station. The listed group 1 
isolation valves were compared with the valves that actually isolate from 
each group 1 isolation signal. The reactor sample valves were listed as 
isolating on all group 1 isolation signals when they actually close on only 
two signals (low low reactor water level and high main steam line 
radiation). Following the identification of the discrepancy, Brunswick 
Station personnel contacted General Electric to verify the adequacy of the 
actual design. 

A review of other BWR/4 technical specifications and discussions with 
General Electric indicate that this discrepancy between the listed technical
specification isolation signals and the actual signals may be widespread. It
appears that at some point in the evolution of BWRs the initiating signals 
for the 

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                                                            IN 83-53       
                                                            August 11, 1983 
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group 1 isolation valves were separated but the change was not reflected in 
the technical specification. This separation has been included in the 
technical specifications of newly licensed plants. 

Following the discovery of the discrepancy in isolation signals at Browns 
Ferry Station the licensee has amended the technical specifications for Unit
2 to reflect the actual logic and expects to amend the technical 
specifications for Units 1 and 3. The personnel at Brunswick Station also 
plan to apply for a change to their technical specification to reflect the 
actual logic. It may be prudent for other BWR owners to compare their listed
technical specifications isolation signals against the actual logic. 

No written response to this notice is required. If you have any questions 
regarding this matter please contact the Regional Administrator of the 
appropriate NRC Regional Office, or this office. 


                                   Edward L. Jordan Director 
                                   Division of Emergency Preparedness 
                                     and Engineering Response 
                                   Office of Inspection and Enforcement 

Technical Contact:  Paul R. Farron, IE
                    (301) 492-4766

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