ML20198K590
| ML20198K590 | |
| Person / Time | |
|---|---|
| Issue date: | 01/05/1998 |
| From: | Stolz J NRC (Affiliation Not Assigned) |
| To: | Green T GENERAL ELECTRIC CO. |
| References | |
| NUDOCS 9801150049 | |
| Download: ML20198K590 (2) | |
Text
1 L
Mr. T. A. Green
_ January 5, 1998 Senior Technical Project Manager BWR Owners' Group Projects General Electric Company 175 Curtner Avenue San Jose, CA 95125
SUBJECT:
REVISED NUMBER OF DATABASE SITES FOR MAIN STEAM LINE ISOLATION VALVE t
(MSIV) LEAKAGE ISSUE
Reference:
Letter to T. Liu, Nuclear Regulatory Commission (NRC), from T. A.
Green, BWR Owner's Group Pro;ects (BWROG), dated September 24, 1997
Dear.Mr. Green:
l The NRC staff is reviewing the EQE Correspondence No. 50120.02-0-002, "EQE Database Power Plant Site Ground Motion Estimates," dated September 22, 1997, which was attached to the referenced letter. We have found some discrepancies in the [QE report and have discussed them with EQE staff members, it is our understanding that EQE will corrr t the discrepancies and submit an amended letter. Assuming that the NRC-review of the amended letter concludes that the ground motion estimates are satisfactory, the number of database sites will be reduced to ten sites, as indicated in Table 1 of the EQE report, for which there are adequate ground motion estimates.
In the supplemental piping earthquake performance data report or November 1995, prepared by EQE and transmitted as an attachment to the BWROG's letter of February 19, 1996, the verification of the seismic ca)acity of the MSIV equipment and piping is based on a much larger set of eart1 quake-plant pairs in which there were re)orted to be many cases of similar equipment experiencing strong eartlaua(e ground motions. Wit' a reduction in the number of database sites from the orig'nal set (which is identified in the November 1995 EQE report) to the current ten, the BWROG is requested to revise the seismic experience database piping data provided in Table 4 of the November 1995 EQE report.
Should the database be reduced, as expected, the BWROG will also need to justify that adequate and statistically sufficient piping and equipment data are still available for the proposed earthquake experience database methodology on the MSly issue.
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p, if you have any questions regarding the above NRC staff comments, please feel WJ free to contact ce at (301) 415-1430.
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Sincerely, al r,
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N John F. Stolz, Director bM.
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%*,,,,, *#g W A8HINGTON, D.C. 3066H001 January 5, 1998 Mr. T. A. Green Senior Technical Project Manager BWR Owners' Group Projects General Electric Company 175 Curtner Avenue San Jose, CA 95125
SUBJECT:
REVISED NUMBER OF DATABASE SITES FOR MAIN STEAM LINE IS':LATION VALVE (MSIV) LEAKAGE ISSUE
Reference:
Letter to T. Liu, Nuclear Regulatory Commission (NRC), from T. A.
Green, BWR Owner s Group Projects (BWROG), dated September 24, 1997
Dear Mr. Green:
The NRC staff is reviewing the EQE Correspondence No. 50120.02-0-002, "EQE Database Power Plant Site Ground Motion Estimates," dated September 22, 1997, which was attached to the referenced letter.
W
. e have found some discrepancies in the EQE report and have discussed them with EQE staff members.
It is our understanding that EQE will correct the discrepancies and submit an amended letter. Assuming that the NRC-review of the amended letter concludes that the ground motion estimates are satisfactory, the number of database sites will be reduced to ten sites, as indicated in Table 1 of the EQE report, for which there are adequate ground motion estimates.
in the supplemental piping earthquake performance data report of November 1995, prepared by EQE and transmitted as an attachment to the BWROG's letter of February 19, 1996, the vertrication of the seismic ca)acity of the MSIV equipment and piping is based on a much larger set of eartiguake-plant pairs in which there were re)orted to be many cases of similar equipment experiencing strong earthquace ground motions.
With a reduction in the number of database sites from the orijinal set (which is identified in the November 1995 EQE report) to tle current ten, the BWROG is requested to revise the seismic experience database piping data provided in Table 4 of the November 1995 EQE report.
Should the database be reduced, as expected, the BWROG will a' Iso need to justify that adequate and statistically sufficient piping and equipment data are still available for the proposed earthquake experience database methodology on the MSly issue, if you have any questions regarding the above NRC staff comments, please feel free to contact me at (301) 415-1430.
Sincerely, r
4JhnF.Stolz,Direpf{or roject Directorate I-2 Division of Reactor Projects - 1/11 Office of Nuclear Reactor Regulation
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