ML20054H097
| ML20054H097 | |
| Person / Time | |
|---|---|
| Site: | Browns Ferry  |
| Issue date: | 06/04/1982 |
| From: | Mills L TENNESSEE VALLEY AUTHORITY |
| To: | James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| References | |
| IEB-80-17, IEIN-80-30, NUDOCS 8206220568 | |
| Download: ML20054H097 (3) | |
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TENNESSEE VALLEY AUTHORiliXO Rmy CH ATTANOOG A. TENNESSEE 37/o1 *
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400 Chestnut Street Tower II 02,liN 0 A3 2$
June 4, 1982 U.S. Nuclear Regulatory Commission Region II ATTN: James P. O'Reilly, Regional Administrator 101 Marietta Street, Suite 3100 Atlanta, Georgia 30303
Dear Mr. O'Reilly:
OFFICE OF INSPECTION AND ENFORCEMENT BULLETIN 80-17, SUPPLEMENT 3 -
RII:JP0 50-259, -260, -296 - BROWNS FERRY NUCLEAR PLANT In my February 10, 1982 letter to you on the subject bulletin supplement, we provided justification for suspension of the functional testing of the scram discharge instrument volume (SDIV) level switches following each scram. We were verbally informed by your staff that the request was denied but that the decision would be reconsidered if we provided additional justification. We, therefore, submit the following information for your reconsideration.
Background
IE Notice 80-30 was issued on August 19, 1980 describing a potential single failure mechanism of the control rod drive control air system which could cause partial opening of the scram outlet valves and a consequential undetected filling of the scram discharge volume (SDV). IE Bulletin 80-17, supplement 3, was subsequently issued on August 22, 1980 requesting specific actions to be taken by the licensees to mitigate this event. Item 2 of this bulletin supplement specifically requested implementation of an interim functional t at of the SDIV level instruments following each scram before returning to power operations.
This interim procedure was required to remtin in effect until
" modifications in addition to Item B.1 of %EB 80-17 supplement No. 1 are completed to substantially increase the reliability of the water level indication in the scram discharge volume (s)."
B206220568 820604 PDR ADOCK 05000259 G
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. Mr. James P. O'Reilly June 4, 1982 On January 9, 1981, we received orders requiring implementation of an automatic system to initiate control rod insertion on low pressure in the control air header to " provide prompt added protection for credible degraded air conditions."
TVA Actions In response to IE Bulletin 80-17, supplement 3, we informed you in my August 29, 1980 letter that we fully complied with the requirements of the supplement including the SDIV level switches functional testing.
In response to item B.1 of IE Bulletin 80-17, supplement 1 and its amplifying IE Bulletin 80-17, supplement 4, we have installed a continuous monitoring system (CMS) on the SDVs. As indicated in my April 21, 1982 letter to you, we have installed and tested a four monitor CMS of much higher reliability than that required by the bulletin supplements.
In response to the orders requiring an automatic scram on low control air header pressure, we have installed instrumentation to induce a reactor protection system (RPS) scram. The instrumentation, power supply, and logic significantly exceed the requirements of the order and are of the same high reliability as all other RPS logic.
Justification for Suspension of Functional Testing Requirements 1.
We have been responsive to the requirements of IE Bulletin 80-17, supplement 3, as described above.
2.
We have installed instrumentation that exceeds the requirements of IE Bulletin 80-17, supplements 1 and 4.
3 We have installed an RPS scram on low air header pressure to specifically address the concerns of IE Bulletin 80-17, supplement 3
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. Mr. James P. O'Reilly June 4, 1982 4.
Based upon items 1, 2, and 3 above, we have met or surpassed the requirements of item 2 of IE Bulletin 80-17, supplement 3, that allows for suspension of the interim functional testing.
5.
Based upon the 20 functional tests performed since January 1,1982 on units 1 and 2, we estimate radiation exposure of 3600 mR/ year with three operating units. We consider this level of exposure unjustifiable and inconsistent with our ALARA goals.
Conclusion We believe we have provided sufficient justification for suspension of the SDIV level switches functional testing as allowed by IE Bulletin 80-17, supplement 3 We again request your prompt consideration of our request to suspend this functional testing in light of the above information.
To the best of my knowledge, I declare the statements contained herein are complete and true.
Very truly yours, TENNESSEE VALLEY AUTHORITY L. M. Mills, Mhnager Nuclear Licensing cc:
Mr. R. C. DeYoung, Director Office of Inspection and Enforcement U.S. Nuclear Regulatory Commission Washington, DC 20555 Mr. R. J. Clark Browns Ferry Project Manager U.S. Nuclear Regulatory Commission 7920 Norfolk Avenue Bethesda, Maryland 20014 Y