Protecting People and the EnvironmentUNITED STATES NUCLEAR REGULATORY COMMISSION
LICENSEE: SIEMENS POWER CORPORATION
SITE: SIEMENS POWER CORPORATION EN NUMBER:31366
DOCKET: 07001257 EVENT DATE: 11-21-96
RX TYPE: EVENT TIME: 00:00
VENDORS: NOTIFY DATE: 11-21-96
EMERGENCY CLASS: N/A REGION: 4 STATE: WA TIME: 15:40
OPS OFFICER: STEVE SANDIN
10 CFR SECTION: CCCC 21.21 UNSPECIFIED PARAGRAPH
10 CFR PART 21 NOTIFICATION OF DEFECT IN 1986 EXEM PWR LBLOCA
MODEL
"THIS FACSIMILE IS TO INFORM THE NRC OF A REPORTABLE DEFECT PER
10 CFR PART 21."
"IN A TELEPHONE CONVERSATION ON OCTOBER 10, 1996, SIEMENS POWER
CORPORATION (SPC) AND ITS CURRENT PWR UTILITY CUSTOMERS WERE
INFORMED THAT THE NRC HAD REJECTED SPC's PROPOSED 1991 CHANGES
MADE TO THE FCTF REFLOOD HEAT TRANSFER CORRELATIONS IN THE
TOODEE2 CODE IN THE APPROVED 1986 EXEM PWR LARGE BREAK LOSS OF
COOLANT ACCIDENT (LBLOCA) EVALUATION MODEL. THESE CHANGES WERE
SUBMITTED TO ELIMINATE A NON-PHYSICAL TREND IN HEAT TRANSFER
COEFFICIENTS AS A FUNCTION OF REFLOOD RATE IN THE 1986 EXEM PWR
LBLOCA EVALUATION MODEL. THE NRC ALSO CONCLUDED, BASED ON THE
INFORMATION AVAILABLE TO THE STAFF, THE NON-PHYSICAL TREND IN THE
1986 EXEM PWR LBLOCA EVALUATION MODEL WAS CONSIDERED TO BE AN
UNACCEPTABLE ERROR. THESE NRC DETERMINATIONS WERE DOCUMENTED IN
A LETTER FROM R.C. JONES (USNRC) TO H.D. CURET (SPC) DATED
OCTOBER 11, 1996. AS A RESULT OF THESE DETERMINATIONS, SPC
PERFORMED A 10 CFR 21 EVALUATION IN ACCORDANCE WITH THE SPC
PROCEDURES. THIS LETTER DOCUMENTS THE RESULTS OF THIS PART 21
EVALUATION."
"THE SPC PART 21 EVALUATION CONCLUDED THE ERROR IN THE FCTF HEAT
TRANSFER CORRELATIONS IN THE 1986 EXEM PWR EVALUATION MODEL TO BE
A SUBSTANTIAL SAFETY DEFECT. THE BASIS FOR THIS CONCLUSION RESTS
ON THE FACT THAT CERTAIN PLANTS ANALYZED WITH THE INTERIM
CORRECTIONS TO THE FCTF HEAT TRANSFER CORRELATIONS EXCEEDED 10
CFR 50.46 LIMITS."
"THE AFFECTED PWR UTILITIES WERE INFORMED OF THE TELEPHONE
CONVERSATION, A MEETING CONDUCTED BY THE NRC HELD ON WEDNESDAY,
OCTOBER 16, 1996 IN ROCKVILLE, MD REGARDING THE IMPACT OF THE
DEFECT ON CALCULATED 10 CFR 50.46 CRITERIA, AND DIRECT
COMMUNICATIONS BETWEEN THE UTILITIES AND SPC. ACTIONS TAKEN AND
TO BE TAKEN TO ADDRESS THE ISSUE ARE TO BE PROVIDED IN A WRITTEN
REPORT TO THE NRC IN COMPLIANCE TO 10 CFR 21.21 (d)(3)(ii)."
