AECM-82-314, Discusses Result of Util Preliminary Assessment of NSSS & Balance of Plant Equipment Located Inside Containment Re Potential Impact of Variable Pool Swell Response Spectra on Seismic Qualification Review Team Qualification

Discusses Result of Util Preliminary Assessment of NSSS & Balance of Plant Equipment Located Inside Containment Re Potential Impact of Variable Pool Swell Response Spectra on Seismic Qualification Review Team Qualification

ML20054M189
Person / Time
Site:	Grand Gulf
Issue date:	07/07/1982
From:	Dale L MISSISSIPPI POWER & LIGHT CO.
To:	Harold Denton Office of Nuclear Reactor Regulation
References
AECM-82-314, NUDOCS 8207120077
Download: ML20054M189 (3)

Text

O MISSISSIPPI POWER & LIGHT COMPANY Helping Build Mississippi P. O. B O X 16 4 0. J A C K S O N, MISSISSIPPI 39205 NUCLEAR PFODUCiloN DEPARTMENT U.S. Nuclear Regulatory Commission Office of Nuclear Reactor Regulation Washington, D.C. 20555 Attention: Mr. Harold R. Denton, Director

SUBJECT:

Grand Gulf Nuclear Station Units 1 and 2 Docket Nos. 50-416 and 50-417 File 0260/L-814.2 SQRT - Assessment of Variable Pool Swell on SQRT Qualification AECM-82/314 Mississippi Power & Light Company (MP&L) has completed a preliminary assessment of the NSSS and BOP equipment located inside containment to determine the potential impact of the variable pool swell response spectra upon the present SQRT qualification of the NSSS and B0P equipment. The result of this assessment is as follows:

A. B0P Equipment The only ef fected equipment are thermocouples purchased under Specification 9645-J-561.0:

1M71-TE-N005A, B, C, D IM71-TE-N012A, B, C, D IM71-TE-N006A, B, C, D IM71-TE-N013A, B, C, D IM71-TE-N007A, B, C, D IM71-TE-N022A, B, C, D IM71-TE-N00FA, B, C, D IM71-TE-N023A, B, C, D IM71-TE-N00,A, B, C, D IM71-TE-N024A, B, C, D IM71-TE-N010A, B, C, D IM71-TE-N026A, B, C, D IM71-TE-N011A, B, C, D IC61-TE-N403A, B B. NSSS Equipment Excluding the HCU's, no equipment is affected. The review of the HCU's is not complete because the new HCU floor RRS curves are currently under development. The results of our evaluation of these new curves will be provided for your review by August 15, 1982. Our assessment of anticipated changes concludes that sufficient margin exists in the existing qualification levels.

Justification for interim operation for the thermocouples and HCU's is provided as follows:

8207120077 820707 AE1Il PDR ADOCK 05000416 P PDR Member Middle South Utilities System

' e t AECM-82/314 MISSI2IIPPI POWER O LI2HT COMPANY Page 2 4

A. Thermocouples

1. The thermocouples identified above are used by the operator for the purpose of post-accident monitoring.

The thermocouples will not be needed until 5% power is exceeded.

2. The thermocouples have been qualified to IEEE 344-1975.

The increase in "g" level due to the variable pool swell is expected to be less than 0.5g's above the existing qualification level. No problem in requalifying is expected.

3. The thermocouples are presently in a requalification program to meet NUREG-0588, Category I requirements. The seismic testing for the thermocouples is scheduled to begin July 17, 1982, with testing to be completed by July 23, 1982.

B. HCU's

1. Bechtel is scheduled to issue the new HCU floor response spectra with the increase of 25% in response spectra (RRS) peak by July 15, 1982.

2. GE is scheduled to complete the review of existing qualification against the new HCU floor response spectra by August 15, 1982.

3. The existing qualification "g" levels for the HCU's contain excessive margin. Any increase in the "g" level for the new HCU floor response spectra will be bounded by the existing qualification. Comparison of the existing '

TRS and RRS is documented in MP&L's letter to the NRC (AECM-81/391) dated October 9, 1981.

If you have any questions or require further information, please contact this office.

Yours truly,

/

L. F. Dale

[

Manager of Nuclear Services RAB/SHH/JDR:Im .

cc: (See Next Page) 1 1

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! e k AECM-82/314 Page 3 i MISCIIOIPPI POWER O LIGHT COMPANY cc: Mr. N. L. Stampley Mr. R. B. McGehee Mr. T. B. Conner Mr. G. B. Taylor j Mr. Richard C. DeYoung, Director j Office of Inspection & Enforcement U.S. Nuclear Regulatory Commission Washington, D.C. 20555 Mr. J. P. O'Reilly, Regional Administrator Office of Inspection & Enforcement Region II '

101 Marietta Street, N.W., Suite 3100 '

Atlanta, Georgia 30303 i

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