ML20132F480
| ML20132F480 | |
| Person / Time | |
|---|---|
| Site: | Fort Calhoun  |
| Issue date: | 12/09/1996 |
| From: | Wharton L NRC (Affiliation Not Assigned) |
| To: | Tira Patterson OMAHA PUBLIC POWER DISTRICT |
| Shared Package | |
| ML20132F483 | List: |
| References | |
| TAC-M74412, NUDOCS 9612240289 | |
| Download: ML20132F480 (3) | |
Text
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t UNITED STATES g
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NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. mas amat k..b December 9,1996 l
Mr. Terry L. Patterson Division Manager - Nuclear Operatic,ns Omaha Public Fower District 4
Fort Calhoun Station FC-2-4 Adm.
Post Office Bcx 3gg Hwy. 75 - North of Fort Calhoun j
Fort Calhoun, Nebraska 68023-03gg
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1
SUBJECT:
FORT CALHOUN STATION, UNIT NO. 1 - REVIEW OF INDIVIDUAL PLANT EXAMINATION (IPE).SU8NITTAL - INTERNAL EVENTS (TAC NO. M74412)
Dear Mr. Patterson:
J Enclosed is the NC Staff Evaluation Report (SER)
.ie Fort Calhoun Station (FCS) Individual Plant Evaluation (IPE) submittal.
internal events and i
internal flood. Also included with the SER are the contractors' (Science &
i Engineering Associates, Inc., Concord Associates, and Scientech Inc.)
Technical Evaluati;.i Reports (TERs).
i During the review, the staff identified certain limitations in the Human Reliability Analysis (HRA). For example, there are some characteristics associated with the modeling of mistakes that can lead to seemingly inconsistent results. The model uses different time / reliability correlations depending on whether actions are verification, rule-based, or "other" actions, whether they occur inside or outside the control room, and whether the operators are burdened.
It appears that differences in quantification results based on these correlations may be significant.
In addition, there appears to i
be no specific guidance as to which actions should be assigned to include l
burden. This factor, also, can affect the estimated failure probability.
Based on the findings discussed in the enclosed reports, the staff concludes that your iPE is complete with regard to the information requested by Generic Letter 88-20 and the associated guidance in NUREG-1335; and the IPE results are reasonable given the Fort Calhoun design, operation, and history. As a result, the staff concludes that the IPE process is capable of identifying the most likely severe accidents and severe aceti nt vulnerabilities, and therefore, the Fort Calhoun IPE has met the tident of Generic Letter 88-20.
g It should be noted that the staff's review primarily focused on Omaha Public h Power District's (the licensee) ability to examine Fort Calhoun for severe accident vulnerabilities. Although certain aspects of the IPE were explored in more detail than others, the review is not intended to validate the s
accuracy of the licensee's detailed findings (or quantification estimates) s that stemmed from the examination. Therefore, this SER does not constitute NRC approval or endorsement of any IPE material for purposes other than those associated with meeting the intent of Generic Letter 88-20.
The staff has identified a weakness in the HRA portion of the IPE and believes that NRC HLE CENTER COPY 240056 9612240289 961209 DR ADOCK 050002 5 L
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a i
i Mr. Terry L. Pratterson Deceraber 9,1996 application of the IPE in support of risk-based regulatory applications, beyond those associated with Generic Letter 88-20, require additional treatment in that area.
l If you have any questions, please contact me at (301) 415-1396.
Sincerely, 3
Original Signed By L. Raynard Wharton, Project Manager Project Directorate IV-2 Division of Reactor Projects - III/IV Office of Nuclear Reactor Regulation Docket No. 50-285
Enclosures:
1.
Safety Evaluation 2.
Technical Evaluation Report cc w/encls:
See next page DISTRIBUTION:
10ccket; File PUBLIC PDIV-2 Reading EGA1 JRoe WBateman RWharton EPeyton WJohnson, RIV RHernan JLane OGC ACRS DOCUMENT NAME:
FCS74412.IPE OFC JDIV-2/PM PDIV-2/LA NAME kIkrton (feYtk 4
DATE 16 / 9 /96 a (o /96 0FF;CIAL RECORD COPY 4
t
Mr. Terry L. Patterson December 9, 1996 cc:
Winston & Strawn ATTN: Perry D. Robinson, Esq.
1400 L Street, N.W.
Washington, DC 20005-3502 Mr. Jack Jensen, Chairman Washington County Board of Supervisors Blair, Nebraska 68008 Mr. Wayne Walker, Resident Inspector U.S. Nuclear Regulatory Commission Post Office Box 309 Fort Calhoun, Nebraska 68023 Regional Administrator, Region IV U.S. Nuclear Regulatory Commission i
611 Ryan Plaza Drive, Suite 1000 Arlington, Texas 76011 Ms. Cheryl Rodgers, LLRW Program Manager Environmental Protection Section Nebraska Department of Health 301 Centennial Mall, South P.O. Box 95007 Lincoln, Nebraska 68509-5007 Mr. James W. Chase, Manager Fort Calhoun Station Post Office Box 399 Fort Calhoun, Nebraska 68023 l
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