ML20212G342
| ML20212G342 | |
| Person / Time | |
|---|---|
| Site: | Grand Gulf  |
| Issue date: | 01/12/1987 |
| From: | NRC |
| To: | |
| Shared Package | |
| ML20212G336 | List: |
| References | |
| RTR-REGGD-01.097, RTR-REGGD-1.097 GL-82-33, TAC-51094, NUDOCS 8701200223 | |
| Download: ML20212G342 (2) | |
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UNITED STATES 8"
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WASHINGTON, D. C. 20555
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ENCLOSURE 1 SAFETY EVALUATION REPORT GRAND GULF NUCLEAR STATION, UNIT NO. 1 DOCKET NO. 50-416 CONFORMANCE TO REGULATORY GUIDE 1.97, REVISION 2
1.0 INTRODUCTION
Mississippi Power and Light Company was requested by Generic Letter 82-33 to provide a report to the NRC describing how the post-accident monitoring instrumentation meets the guidelines of Regulatory Guide (R.G.) 1.97 as applied to emergency response facilities. The licensee's response to R.G. 1.97 was provided by. letters dated February 28, 1985 and February 14, 1986.
A detailed review-and technical evaluation of'the licensee's submittals was performed by EG&G Idaho, Inc., under contract to the NRC, with general supervision by the NRC staff. This work was reported by EG&G in the Technical Evaluation Report (TER), "Conformance to R.G. 1.97, Grand Gulf Nuclear Station, Unit No.1," dated March 1986 (attached). We have reviewed this report and concur with'the conclusion that the licensee either conforms to, or has adequately justified deviations from the guidance of R.G. 1.97 for each post-accident monitoring variable except for neutron flux.
2.0 EVALUATION Subsequent to the issuance of the generic letter, the NRC held regional meetings in February and March 1983 to answer licensee and applicant questions and concerns regarding the NRC policy'on R.G. 1.97.
At these meetings, it was established that the NRC review would only address exceptions taken to the guidance of R.G. 1.97.
Where licensees or appl'icants explicitly state that instrument systems conform to the provisions of the regulatory guide, no staff review would be necessary for those items. Therefore, the review performed and reported by EG&G only addresses exceptions to the guidance of R.G. 1.97.
This Safety Evaluation addresses the licensee's submittals based on the review policy described in the NRC regional meetings and the conclusions of the review as reported by EG&G.
We have reviewed the evaluation performed by EG&G contained in the enclosed TER and concur with its basis and findings with the exception of the issue related to neutron flux monitoring instrumentation which is 8701200223 870112 PDR ADOCK 05000416 p
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' evaluated below and is not discussed within the enclosed TER. Therefore, the Grand Gulf design either conforms to, or the licensee has provided acceptable justification for deviations from the guidance of^R.G. 1.97 for each post-accident. monitoring variable except for neutron flux.
Regulatory Guide 1.97, Revision 2 recommends that the neutron flux monitoring system comply with Category 1 design criteria including seismic and environmental qualification. However, existing neutron flux monitoring systems for BWRs, including Grand Gulf, are not typically fully' environmentally and seismically qualified.
It is the staff's understanding that a Category 1 system that will meet all the required design criteria is an item currently under development by industry.
By letter dated February 28, 1985, the licensee has provided infonnation which infers that the subject instrumentation would only be needed in the event of an anticipated trans.ient without scram (ATWS) and that such an event would not result in an environment more severe than a normal operating environment. However, it is the staff's position that neutron
' flux instrumentation is required for long-term monitoring purposes as related to the mitigation of any inadvertent boron dilution event or other reactivity addition situation resulting from accidents.
In addition to providing justification for not having to fully environmentally qualify the neutron flux monitorin'g system, the licensee has committed to continue to follow industry development of such equipment and will either (1) implement a new system in the future that will comply with the Category 1 design requirements or (2) upgrade the present system t(t provide the necessary reliability based on the Grand Gulf specific design requirements. The staff finds this commitment to be acceptable with the understanding that the staff's position stated above will be adhered to during the development and implementation of a Category 1 neutron flux monitoring system.
3.0 CONCLdSION Based on the above evaluation which included the staff's review of the enclosed Technical Evaluation Report and the licensee's submittals, we find that the Grand Gulf Nuclear Station design is acceptable with respect to the provisions of R.G.1.97, Revision 2 except for the instrumentation associated with the neutron flux variable.
It is the staff's position that the licensee shall install and have operational monitoring instrumentation for the subject variable which fully conforms to the recommendations of R.G. 1.97, Revision 2.
Operating license condition 2.C.(36) requires that the installation of flux monitoring instrumentation conforming to RG 1.97 be installed prior to startup following the second refueling outage.
It has been concluded by the staff that the existing neutron flux instrumentation is acceptable for interim operation pending satisfactory implementation of a fully qualified indication system.
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