United States Nuclear Regulatory Commission - Protecting People and the Environment

Bulletin 79-14: Supplement, Seismic Analysis for As-Built Safety-Related Piping Systems

                                                            SSINS:  6820 
                                                            Accession No: 
                                                            7968080360 

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

                               August 15, 1979

                                        Supplement IE Bulletin No. 79-14 

SEISMIC ANALYSIS FOR AS-BUILT SAFETY-RELATED PIPING SYSTEMS 

Description of Circumstances 

IE Bulletin No. 79-14 was issued on July 2, 1979 and revised on July 18, 
1979.  The bulletin requested licensees to take certain actions to verify 
that seismic analyses are applicable to as-built plants. This supplement to 
the bulletin provides additional guidance and definition of Action Items 2, 
3, and 4. 

To comply with the requests, in IE Bulletin 79-14, it will be necessary for 
licensees to do the following: 

2.   Inspect Part of the Accessible Piping 

     For each system selected by the licensee in accordance with Item 2 of 
     the Bulletin, the licensee is expected to verify by physical 
     inspection, to the extent practicable, that the inspection elements 
     meet the acceptance criteria. In performing these inspections, the 
     licensee is expected to use measuring techniques of sufficient accuracy 
     to demonstrate that acceptance criteria are met. Where inspection 
     elements important to the seismic analysis cannot be viewed because of 
     thermal insulation or location of the piping, the licensee is expected 
     to remove thermal insulation or provide access. Where physical 
     inspection is not practicable, e.g., for valve weights and materials of 
     construction, the licensee is expected to verify conformance by 
     inspection of quality assurance records. If a nonconformance is found, 
     the licensee is expected in accordance with Item 4 of the Bulletin to 
     perform an evaluation of the significance of the nonconformance as 
     rapidly as possible to determine whether or not the operability of the 
     system might be jeopardized during a safe shutdown earthquake as 
     defined in the Regulations. This evaluation is expected to be done in 
     two phases involving an initial engineering judgement (within 2 days), 
     followed by an analytical engineering evaluation (within 30 days). 
     Where either phase of the evaluation shows that system probability is 
     in jeopardy, the licensee is expected to meet the applicable technical 
     specification action statement and complete the inspections required by 
     Item 2 and 3 of the Bulletin as soon as possible. The licensee must 
     report the results of these inspections in accordance with the 
     requirements for content and schedule as given in Item 2 and 3 of the 
     Bulletin. 

3.   Inspect Remaining Piping 

     The licensee is expected to inspect, as in Item 2 above, the remaining 
     safety-related piping systems which were seismically analyzed and to 
     report the results in accordance with the requirements for content and 
     schedule as given in Item 3 of the Bulletin. 
.

Supplement IE Bulletin No. 79                              Page 2 of 2 
August 15, 1979 

4A.  Evaluate Noncomformances 

     With regard to Item 3A for the Bulletin, the license is expected to 
     include in the initial engineering judgement his justification for 
     continued reactor operation.  For the analytical engineering 
     evaluation, the licensee is expected to perform the evaluation by using 
     the same analytical technique used in the seismic analysis or by an 
     alternate, less complex technique provided that the licensee can show 
     that it is conservative. 

     If either part of the evaluation shows that the system may not perform 
     its intended function during a design basis earthquake, the licensee 
     must promptly comply with applicable action statements and reporting 
     requirements in the Technical Specifications. 

4B.  Submit Nonconformance Evaluations 

     The licensee is expected to submit evaluations of all nonconformances 
     and, where the licensee concludes that the seismic analysis may not be 
     conservative, submit schedules for reanalysis in accordance with Item 
     4B of the Bulletin or correct the noncomformances. 

4C.  Correct Nonconformances 

     If the licensee elects to correct nonconformances, the licensee is 
     expected to submit schedules and work descriptions in accordance with 
     Item 4C of the Bulletin. 

4D.  Improve Quality Assurance 

     If noncomformances are identified, the licensee is expected to evaluate
     and improve quality assurance procedures to assure that future 
     modifications are handled efficiently. In accordance with Item 4D of 
     the Bulletin,  the licensee is expected to revise design documents and 
     seismic analyses in a timely manner. 

The schedule for the action and reporting requirements given in the Bulletin
as originally issued remains unchanged. 
Page Last Reviewed/Updated Tuesday, July 23, 2013