ML20199G708
| ML20199G708 | |
| Person / Time | |
|---|---|
| Site: | San Onofre  |
| Issue date: | 01/20/1999 |
| From: | Clifford J NRC (Affiliation Not Assigned) |
| To: | Ray H SOUTHERN CALIFORNIA EDISON CO. |
| References | |
| TAC-MA1549, TAC-MA1550, NUDOCS 9901220382 | |
| Download: ML20199G708 (3) | |
Text
January 20, 1999 f
Mr. Hirold B. Rry Ex:cutivs Vice Presid:nt Southern California Edison Company s
San Onofre Nuclear Generating Station P. O. Box 128 Gan Clemente, California 92674-0128
SUBJECT:
REQUEST FOR ADDITIONAL INFORMATION ON CONTAINMENT ISOLATION VALVE COMPLETION TIME TECHNICA!. lPECIFICATION (TAC NOS.
MA1549 AND MA1550)
Dear Mr. Ray:
In a letter dated April 6,1998, Southern California Edison (SCE) submitted a request for amendment to the San Onofre Nuclear Generating Station (SONGS) Units 2 and 3 technical specifications to make the completion time for containment isolation valves the same as for the engineered safeguards features for the systems to which they are associated.
Your submittal did not include sufficient information for the staff to complete its review of your supporting risk analysis. This information was discussed in a conference call with your staff on l
December 15,1998. As discussed in that conference call, there was some basic and general information that was necessary for the staff to conduct a detailed review of your risk analysis.
To complete our review, we request that you provide the additional information identified in the enclosure within 60 days of the date of this letter. While the enclosure does identify some specific questions and issues, we provide this information now to provide the benefit of the staff's review to date. However, a detailed review of your submittal and any supplemental information may result in additionalinformation needs based on this detailed review. This information and the schedule have been discussed with Jack Rainsberry of your staff.
P! ease call me at (301) 415-1352 if you have any questions.
Sincerely, Original Signed By Jaines W. Clifford, Senior Project Manager Project Directorate IV-2 Division of Reactor Projects Ill/IV Office of Nuclear Reactor Regulation Docket Nos. 50-361 DISTRIBUTION:
and 50-362 Docket File EPeyton PUBLIC SMalik (SPSB)
Enclosure:
Request for Additional Information PDIV-2 R/F AEl-Bassioni (SPSB)
EAdensam KBrockman, RIV-IV WBateman OGC cc w/ encl: See next page JClifford ACRS DOCUMENT NAME: G:\\SOA1549.RAI To rec *in a copy of this document. Indicate in the box:
"C" = Copy without enclosures "E" = Copy with enclosiacs "N" = No copy OFFICE PDLV-2/PM l PDIV-2/LA l 7
NAME JCfrfford EPeytonM I
DATE 01/pV99 01/ ICV 99 k
l OFFICIAL RECORD COPY 9901220392 990120 pg;: r n r c'-
~~ ^ 7 PDR ADOCK 05000361 y
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+
PDR p
/
1 Mr. Harold B. Ray January 20, 1999 i
4 i
cc w/encls:
i Mr. R. W. Knoger, Vice President Resident inspector / San Onofre NPS Southem Califomia Edison Company clo U.S. Nuclear Regulatory Commission j
San Onofre Nuclear Generating Station Post Office Box 4329 i
P. O. Box 128 San Clemente, Califomia 92674 San Clemente, Califomia 92674-0128 Mayor Chairman, Board of Supervisors City of San C!emente County of San Diego 100 Avenida Presidio
^
1600 Pacific Highway, Room 335 San Clemente, Califomia 92672 San Diego, Califomia 92101 l
Mr. Dwight E. Nunn, Vice President Alan R. Watts, Esq.
Southem Califomia Edison Company Woodruff, Spradlin & Smart San Onofre Nuclear Generating Station 701 S. Parker St. No. 7000 P.O. Box 128 1
i Orange, Califomia 92668-4702 San Clemente, Califomia 92674-0128 j
l Mr. Sherwin Harris i
Resource Project Manager i
Public Utilities Department City of Riverside 3900 Main Street
)
3 Riverside, Califomia 92522 Regional Administrator, Region IV U.S. Nuclear Regulatory Commission Harris Tower & Pavilion 611 Ryan Plaza Drive, Suite 400 Arlington, Texas 76011-8064 Mr. Michael Olson i
San Onofre Liaison San Diego Gas & Electric Company P.O. Box 1831 San Diego, Califomia 92112-4150 Mr. Steve Hsu Radiologic Health Branch State Department of Health Services Post Office Box 942732 Sacramento, Califomia 94234 1
jt o
REQUEST FOR ADDITIONAL INFORMATION PROPOSED CHANGE TO CONTAINMENT ISOLATION VALVE COMPLETION TIMES 3.QUTHERN CALIFORNIA EDISON COMPANY l
SAN ONOFRE NUCLEAR GENERATING STA PON. UNITS 2 AN i i
QQ_QJfiT NOS 50-361 AND 50-362 i
j Tier 1:
Risk imoset and PRA Val 4ty l
1.
What is the SONGS updated boseline CDF, baseline LERF, and what is the impact of the proposed TS change CDF, ICCDP, LERF, and ICLERP? Do these vs!Ues and the i
values given on page 3 of your submittalinclude shutdove risk and risks stemming from both intemal rau extemal events?
2.
In modeling the proposed TS change, what values did you use for the unavailabilities of these valves? What is the effect of the unavailability of the valves on the unavailability of the related system? Were all of the D.1, and D.2. valves modeled in the PRA? If not, how are the valves accounted for in the PRA?
3.
What event sequences are important to the proposed change? What are the major factors contributing to their risk significance?
t J
4.
Describe how uncertainties were considered? Were sensitivity studies perfonned to address the impact of variation in preventive maintenance times?.
I 5.
During MOVATS testing, what is the position of the valve and could the valve be opened to perform its ESF function? If so,is this recovery credited in the PRA? The required action in the TS is to " secure the inoperable valve (s) in its ESFAS position."
Does this mean to manually lock open the valve?
Tier 2:
Consideration of Hiah Risk Confiaurations Provide details about compensatory measures taken before a D.1. or D.2. containment isolation valve is taken out of service.
Tier 3: Confiauration Risk Manaoement Proaram Describe how the ' SONGS CRMP is used to reduce risk when a D.1. or D.2. containment isolation valve is taken out of service.