ML19341B366
| ML19341B366 | |
| Person / Time | |
|---|---|
| Site: | Sequoyah  |
| Issue date: | 01/13/1981 |
| From: | Mark J Advisory Committee on Reactor Safeguards |
| To: | Ahearne J NRC COMMISSION (OCM) |
| References | |
| ACRS-R-0911, ACRS-R-911, NUDOCS 8101300814 | |
| Download: ML19341B366 (1) | |
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jo UNITED STATES NUCLEAR REGULATORY COMMISSION o
ADVISORY COMMITTEE ON REACTOR SAFEGUARDS I
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Honorable John F. Ahearne 3
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SUBJECT:
REPORT ON THE SEQUOYAH NUCLEAR POWER PLANT, UNITS 1 AND 2
Dear Dr. Ahearne:
During the 249th meeting of the ACRS, January 8-10, 1981, we discussed the NRC Staff s review of the interim hydrogen control system proposed for use in the Sequoyah Nuclear Power Plant, Unit 1.
This matter was also discussed at a Subcommittee meeting on January 6,1981. We have previously commented on this subject in our report dated July 15, 1980 and in two reports dated September 8, 1980.
In this previous correspondence we indicated that distributed ignition systems of the type being considered for use in the Sequoyah plant could pro-vide an improved capability for controlling the burning of a 1arge amount of hydrogen and that the use of such a system would probably reduce risk.
We now believe thct the results of analyses and tests which we have discussed with the NRC Staff and the Tennessee Valley Authority (TVA) supoort these conclusions. The NRC Staff and TVA are continuing to work together to resolve the issue of the survivabilicy of the equipment within containment which is important to safety. Although much further study 1s needed to determine the ability of the many essential components to continue to operate after exposure to the conditions imposed by possible hydrogen burning, the conditions imposed I
will not be aggravated by the operation of the ignition system, and in all probability will be less severe. We wish to be kept informed of the PRC Staff's and TVA's progress in this work.
We concur with the NRC Staff recommendation to allow the operation of the Interim Distributed Ignition System and believe that this system will provide improved protection against breach of containment in the event that a substan-tial quanti:y of hydrogen is generated. We recomend that the NRC Staff and' TVA continue their efforts to describe the perfonnance characteristics of the system over a broader range of conditions.
l Sincerely, 1
J. Carson Mark Chairman i
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