ML20205P543
| ML20205P543 | |
| Person / Time | |
|---|---|
| Site: | Nine Mile Point  |
| Issue date: | 03/26/1987 |
| From: | Mangan C NIAGARA MOHAWK POWER CORP. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| (NMP2L-1011), NUDOCS 8704030307 | |
| Download: ML20205P543 (3) | |
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M Y NIAGARA HUMOHAWK Nif0E MILE POINT-UNIT 2/P.O. BOX 63. LYCOMING, NY 13093/ TELEPHONE (315) 343-2110 March 26,1987 (NMP2L 1011) i I
United States. NJclear Regulatory, Commission Document Control Desk Washington, DC 20555 Re: Nine Mile Point - Unit 2 Docket No. 50-410 -
4 Gen tlemen:
Please find attached our formal response to the totice of Violation dated February 11, 1987, accompanying Inspection Report No. 50-410/86-65.
Very truly yours, NI AGAR A MOHMK POWER CORPOR ATION
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C. V. Man n Senior Vice President CWi/AZP/jmf (0184G) cc:
Regional Administrator, Region I Sr. Resident Inspector, W. A. Cook fNP2 SSC File s
Project File (2) i
.l 8704030307 870326 PDR ADOCK 05000410 l
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NIAGARA M0HMK POWER C0RPORATION NINE MILE POINT - UNIT 2 DOCKET N0. 50-410 i
RESPONSE TO NOTICE OF VIOLATION Violation 86-65-01 10 CFR 50, Appendix B,
Criterion XVI req uires that conditions adverse to quality be promptly iden ti fied, the cause determined and proper corrective action taken to preclude repetition.
NMPC Quality Assurance Topical Report, Section 16, Corrective Action, requires that for significant conditions adverse to quality, corrective action includes determining the cause and exten t of the condition and takin g appropriate action to minimize similar problems in the future.
Contrary to the above, on December 15,1986, a thit 2 Scram Discharge Volume (SDV)
High Level trip occurred subsequent to resetting a scram signal resulting from operator er ror.
A similar SDV High Level Trip occurred on Novenber 5, 1986.
Licensee corrective action in response to the November 5 reactor trip, as documented in LER No. 86-01, was not effective in preventing the automatic reactor trip on Decenber 15.
1.
Response
Niagara Nhawk Power Corporation has determined that the event described above represents a violation of 10CFR50 Appendix B, Criterion XVI and is not in compliance with the tNPC Quality Assurance Topical Report, Section 16, Corrective Action.
2.
Corrective Actions The design of the fNP2 scram discharge volume (SDV) is such that upon a scram with all-rods-in and the reactor at 0 psi g, the SDV high level scram is not immediately actu ated.
In addition, the length of time required to re-o pen the SDV vent and drain valves (approximately 3
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minutes) results in scram discharge water draining from the SOV headers into the ins trument volume causing an SDV high 1evel scram 4ile the valves are still opening.
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4 x
3..
,9 x
s In each of. the events, the operator f' ailed to place the SDV high level switch to " bypass" prior to resetting the initial scram (as there was no highilevel' scram signal), and thus incurred a second scram when the SDV-high level occurred.
After the first ev en t, a rev is'icn was made to the Dlant Shutdown Procedure, N2-0P-101C to emphasize placing the SDV high, level switches to
" bypass " prior to resettin g as scr am.
Howev er,. the rev ision was apparen tly unclear to ' operations personnel and 'wn inct - explained sufficiently so as to prevent a recurrence.
l' After the second event, the Post Scram Recovery <ection of the procedure was rewritten to clearly require placing the SDV, high level switches to
" bypass" prior to resetting any scraiand to ensure that the 'SDV vent and s
drain vahes: are open and applicable annuncia' tors are cleared prior to
' ' returning the switches to " normal"..
3.
Preventative Actions A.
A review of the simulation model relative to this even't has been performed to ensure that the mocel, accurately reflects the actual time celay between the initial scram'and the subsequent scram due to hi gh Scram Discharge Volume level.
Our ' analysis-has shown the simulator model to be correct-for the plant conditions of an =all rods in, 0 psig reactor scram.
i Specifi c hands on simulator training will.be provided to all operators to ensure.that they understand why the event occurred and the proper actions which should be taken to ' prevent this inciden t from occurring again.
B.
There is an -- inher ent tima delay between trainin g modification implemen tation and the time all operators receiv.e the modified training.
A " Lessons Learned". book has been placed in the Control Room to quickly inform Operations personnel of. significant procedural
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changes or other events.requirir.g their attention.
This event has been included in~ this bcck.
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4 4.
Compliance Niagara Mohawk Power; Corporation has tak en corrective and preventive actions to preclude recurrence of this ' violation as stated in Licensing Event Report 86-19 submitted 4 January 19, 1987.
Rotational training' for personnel on the revised procedure will be complete by March 30, 1987, while simulator training will be complete by July 1987.
With the above stated actions we believe that complia9ce'will be achieved.
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