ML20064G476

Discusses Status of Containment Concerns.Final Rept from Containment Issues Review Panel Will Be Submitted by Mar 1983.Responses to Consultants Delayed Due to Reallocation of Technical Resources

ML20064G476
Person / Time
Site:	Grand Gulf
Issue date:	12/31/1982
From:	Dale L MISSISSIPPI POWER & LIGHT CO.
To:	Harold Denton Office of Nuclear Reactor Regulation
References
AECM-82-641, TAC-49995, TAC-49996, NUDOCS 8301110513
Download: ML20064G476 (4)

Text

o 4 MISSISSIPPI POWER & LIGHT COMPANY Helping Build Mississippi P. O. B OX 1640, J A CK S ON, MIS SISSIP PI 3 92 05 December 31, 1982 NUCLEAR PRODUCTION 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 License No. NPF-13 File: 0260/0272/L-869.9 Humphrey Containment Concerns AECM-82/641

References:

(1) Letter from Mark III Containment Issues Owners Group to H. R. Denton dated September 24, 1982 (2) Letter Number AECM-82/497 From L. F. Dale to H. R. Denton dated October 22, 1982 (3) Letter Number AECM-82/540 From L. F. Dale to H. R. Denton dated November 18, 1982 (4) Letter Number AECM-82/574 From L. F. Dale to H. R. Denton dated December 3, 1982 Mississippi Power & Light (MP&L) Company committed to respond to a number of questions raised by your staff's consultants in reference letter 2. MP&L committed to address two additional concerns beyond the scope of the original "Humphrey Concerns" in reference letter 3. Responses to more than 50% of these questions were provided in reference letters 2 and 4.

Reference letter one discusses the formation of the Containment Issues i

Review Panel which is being funded by the Mark III Containment Issues Owners Group at the request of the Nuclear Regulatory Commission. This review panel has requested several clarifications of the work which has been submitted to your staff. In order to support expeditious completion of the review panel's work, MP&L has reallocated our available technical resources to respond to the review panel's questions. This reallocation of technical resources will result in some delay in completing responses to the questions raised by your consultants. At present, MP&L intends to submit the final report from the Containment Issues Review Panel and responses to all questions raised by your consultants by mid-March, 1983. This date is dependent upon the timely completion of the review panel's work.

MP&L remains committed to providing final resolution to the Humphrey Concerns. All of the initial work which MP&L undertook to address the Humphrey Concerns is now complete. The additional work necessary to address Et301110513 821231 PDR ADOCK 05000416 O@(

T8 P PDR Member Middle South Utilities System

1 6 e AECM-82/641 MISSISSIPPI POWER O LIZHT COMPANY ' #82

. questions raised by your consultants will be completed as the appropriate technical resources become available. Attachment I to this letter provides a complete list of all'open questions for which MP&L will prepare responses.

l Yours truly, ,

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Ill &

L. F. Dale Manager of Nuclear. Services RAW /SHH/JDR:rg Attachment cc: Mr. N. L. Stampley (w/a)

Mr. R. B. McGehee (w/a)

Mr. T. B. Conner (w/a)

Mr. G. B. Taylor (w/a)

Mr. Richard C. DeYoung Director (w/a)

Office of Inspection & Enforcement U. S. Nuclear Regulatory Commission Washington, D. C. 20555 Mr. J. P. O'Reilly, Regional Administrator (w/a)

Office of Inspection and Enforcement U.S. Nuclear Regulatory Commission Region II 101 Marietta St., N.W., Suite 3100 Atlanta, Georgia 30303 l

l

. i 1 +1 - . :

Attachment 1 to AECM-82/641 LIST OF QUESTIONS FOR WHICH MP&L IS PREPARING A RESPONSE I.1.4 Evaluate the numerical impact on prediction for encroachment effects of-uncertainties in analytical assumption.

'I.1.5 Define the sensitivity of local encroachment analytical results to assumptions regarding time at which breakthrough occurs in the bulk pool.

I.6.1 Quantify the maximum lateral loads which could be applied to the RHR heat exchanger reliaf valve discharge line as a result of chugging in the discharge line.

I.6.2 Evaluate condensation oscillation loads which could be produced by discharges from the relief valve discharge line.

.I.A The main steam SRV lines enter the suppression pool at an angle.

Consequently, the additional five feet of submergence produced by upper pool dump may actually increase the length of submerged SRV discharge line by as much as eight feet. Although this change should not adversely effect the air clearing loads, it may change the SRV piping thrust loads, i

I.B.

, The location of SRV quenchers under the TIP platform may produce changes in the SRV quencher loads.

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