IR 05000275/1997014
| ML16343A713 | |
| Person / Time | |
|---|---|
| Site: | Diablo Canyon  |
| Issue date: | 10/06/1997 |
| From: | Merschoff E NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV) |
| To: | Rueger G PACIFIC GAS & ELECTRIC CO. |
| Shared Package | |
| ML16342D813 | List: |
| References | |
| 50-275-97-14, 50-323-97-14, EA-97-369, NUDOCS 9710070381 | |
| Download: ML16343A713 (12) | |
Text
CATEGORY 2 REGULATORY INFORMATION DISTRIBUTION SYSTEM (RIDS)
ACCESSION NBR:9710070381 DOC.DATE: 97/10/06 NOTARIZED: NO DOCKET FACIL:50-275 Diablo Canyon Nuclear Power Plant, Unit 1, Pacific Ga 05000275
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50-323 Diablo Canyon Nuclear Power Plant, Unit 2, Pacific Ga 05000323 AUTH.NAME
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AUTHOR AFFILIATION ERSCHOTT,E.W.
Region 4 (Post 820201)
RECIP.NAME RECIPIENT AFFILIATION RUEGERgG.M.
Pacific Gas
& Electric Co.
SUBJECT:"Discusses 970922 predecisional enforcement conference in Arlington,TX re insp repts 50-275/97-14
& 50-323/97-14
&
two apparent violations related to check valves in drain lines from auxiliary saltwater sys pump vaults.
DISTRIBUTION CODE:
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TITLE: General (50 Dkt)-Insp Rept/Notice of Violation Response NOTES:
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NRR/DRCH/HHFB NRR/DRPM/PERB OE DIR RGN4 FILE
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N NOTE TO ALL "RIDS" RECIPIENTS:
PLEASE HELP US TO REDUCE WASTE. TO HAVE YOUR NAME OR ORGANIZATION REMOVED FROM DISTRIBUTION LISTS OR REDUCE THE NUMBER OF COPIES RECEIVED BY YOU OR YOUR ORGANIZATION, CONTACT THE DOCUMENT CONTROL DESK (DCD)
ON EXTENSION 415-2083 TOTAL NUMBER OF COPIES REQUIRED:
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. UNITED STATES NUCLEAR REGULATORY COMMISSION REGION Iv 611 RYAN PLAZADRIVE, SUITE 400
SUBJECT:
NOTICE OF VIOLATION (NRC'INSPECTION REPORT 50-275/97-14; 50-323/97-14)
Dear Mr. Rueger:
This is in reference to the predecisional enforcement conference conducted in the NRC's Arlington, Texas office on September 22, 1997, with you and other Pacific Gas ItI Electric (PGSE) representatives.
The conference was conducted to discuss two apparent violations of NRC requirements related to check valves in the drain lines from the Auxiliary Saltwater System (ASW) pump vaults at the Diablo Canyon Nuclear Power Plant (Diablo Canyon).
These issues were discussed in NRC Inspection Report 97-14, which was issued
September 8, 1997.
In addition to the apparent violations, the report discussed an unresolved item involving whether PGIlIE should have been entering Technical Specification action requirements when drain line check valves were removed for maintenance.
Based on the information developed during the inspection, and the information that PGSE provided during the conference, the NRC has determined that violations of NRC requirements occurred.
These violations are cited in the enclosed Notice of Violation. The j
circumstances surrounding the violations were described in detail in the subject inspection,
/
report.
Briefly, the first violation involves a failure to meet the requirements of 10 CFR 50.65, the NRC's maintenance rule, in that these check valves were not being effectively maintained to assure they performed their intended function.
This resulted in recurring instances of these valves. becoming clogged with debris and sticking open.
The second violation involves a failure to consistently document these occurrences on "action request" forms.
The third and final violation involves the failure to comply with the requirements of Technical Specification 3.0.3 when check valves were removed from both trains of the Unit 1 ASW system for approximately 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> in 1991.
This violation is based on information PGRE developed in response to the unresolved item in the inspection report and provided at the conference.
As PGSE stated at the conference, the root cause for-these violations appears to be a failure, despite several. opportunities, to recognize the relationship between the functionality of these check valves and the operability of the ASW system, a risk-05000275 PDR ADOCK 0 llllilllllllllllllllllllll)IIIIIIIIIIII
Pacific Gas and Electric Company'2-significant system at Diablo Canyon.
These valves are designed to prevent backflow through the drain lines, and thus protect the ASW pumps from possible flooding conditions in the intake structure which would render the pumps inoperable.
The most significant-missed opportunity occurred in 1991 when a non-conformance report (NCR) was initiated to evaluate the incident which is the subject of Violation C, when both check valves in the Unit 1 pump vault drain lines were simultaneously removed.
As you acknowledged at the conference, this NCR was inappropriately closed, despite the on-site review committee (OSRC) expressing disagreement with the engineering evaluation of this incident.
The continuing failure to recognize the importance of these valves appears to have contributed to the failures to document recurring problems with these valves (Violation B),
which prevented their being placed in an appropriate preventive maintenance program (Violation A), and prevented effective corrective action to preclude this recurring condition.
As PGSE discussed at the conference, several actions were taken in response to these violations, including: 1) maintenance and/or modifications to the ASW pump vault floor drains, drain lines and check valves to assure operability; 2) increased inspection of check valves to assure that enhancements are effective in preventing clogging; 3) placement of the check valves in maintenance rule goal-setting; 4) a review of other Class II equipment for similar failures to recognize the importance of the equipment to safety systems; 5) a review of preventive maintenance records for similar failures to initiate action requests; 6)
a review of the Maintenance Rule program for similar failures to maintain Class II equipment; and 7) plans for increased involvement by system engineers in assuring that recurring problems are addressed in accordance with the Maintenance Rule.
While the violations discussed above are not insignificant, we acknowledge, based on the actions that you took in response, that these concerns appear isolated to these particular check valves and are not indicative of programmatic concerns about maintenance of similar equipment.
It also appears that the sequence of events associated with a tsunami or a circulating water pipe break that would result in flooding the ASW pump vaults is highly unlik'ely, and that alarms and other indications of the potential for flooding would give operations personnel ample time to react and mitigate the consequences.
Finally, in the event that ASW pumps were lost, you had equipment and procedures in place to use the fire water system to provide cooling water to the centrifugal charging pumps to assure reactor coolant pump seal injection and prevent seal failure.
After considering all of the circumstances of this case, the NRC has determined that the violations should be classified at Severity Level IV, in accordance with the "General Statement of Policy and Procedure for NRC Enforcement'ctions" (Enforcement Policy),
NUREG-1 600.
You are required to respond to this letter and should follow the instructions specified in the enclosed Notice when preparing your response.
In your response, you should document the specific actions taken and any additional actions you plan to prevent recurrence.
The
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Pacific Gas and Electric Company-3-NRC will use your response, in part, to determine whether further enforcement. action is necessary to ensure compliance with regulatory requirements.
In accordance with 10 CFR 2.790 of the NRC's "Rules of Practice," a copy of this letter, its enclosure, and your response will be placed in the NRC Public Document Room (PDR).
Sincerely, Ellis W. Mersch Regional Adm'strator Dockets:
50-275; 50-323 Licenses:
Notice of Violation cc w/Enclosure:
Dr. Richard Ferguson Energy Chair Sierra Club California 1100 lith Street, Suite 311 Sacramento, California 95814 Ms. Nancy Culver San Luis Obispo Mothers for Peace P.O. Box 164 Pismo Beach, California 93448 Chairman San Luis Obispo County Board of Supervisors Room 370 County Government Center San Luis Obispo, California 93408 Mr. Truman Burns)Mr. Robert Kinosian California Public Utilities Commission 505 Van Ness, Rm. 4102 San Francisco, California 94102
Pacific Gas and Electric Company Robert R. Wellington, Esq.
Legal Counsel Diablo Canyon Independent Safety Committee 857 Cess Street, Suite D Monterey, California 93940 Mr. Steve Hsu Radiologic Health Branch State Department of Health Services P.O. Box 942732 Sacramento, California 94234 Christopher J. Warner, Esq.
Pacific Gas and Electric Company P.O. Box 7442 San Francisco, California 94120 Robert P. Powers, Vice President and Plant Manager Diablo Canyon Power Plant P.O. Box 56 Avila Beach, California 93424 Managing Editor Telegram-Tribune 1321 Johnson Avenue P.O. Box 112 San Luis Obispo, California 93406
Pacific Gas and Electric Company-5-bcc w/Enclosure:
PDR LPDR SECY CA EDO (0-17G21)
DEDO (0-17G21)
OE:EAFile (0-7H5)
OGC (0-15B18)
NRR (0-12G18)
SBloom, NRR (013E16)
OC/LFDCB (T-9E10)
I
UDOCS EC's:
Rl, Rll, Rill PA (0-2G4)
OIG (T-5D28)
OE (0-7H5)
OI (0-3E4)
OGC (0-15B18)
NRR/ADP (0-12G18)
OC/DAF (T-9E10)
AEOD (T-4D18)
RA Reading File RIV Files PAO RSLO HWong E-MAILDISTRIBUTION:
OEMAIL TPGwynn (TPG)
GSanborn (GFS)
BHenderson (BWH)
CHackney (CAH)
Art Howell (ATH)
KPerkins (KEP)
DAllen (DBA)
GSanborn-EAFile MIS Coordinator JDyer (JED2)
WBrown (WLB)
GMVasquez (GMV)
MHammond (MFH2)
DKunihiro (DMK1)
DChamberlain (DDC)
HWong (HJW)
KBrockman (KEB)
DOCUMENT NAME: GAEA)DRAFT+A'97369,';DFT To receive copy of document, Indicate in box: "C" = Copy without enci ures
"E" ~ Copy w enciosures "N""-No copy EO SA 09/26/97 RA MERS H
//7 C:DRP/E WO G
97 D:DRP GWYNN g/+97 RC WBRO QP/ /97 OFFICIAL RECORD COPY DRA DYER
/5/97