ML20151V136
| ML20151V136 | |
| Person / Time | |
|---|---|
| Site: | San Onofre  |
| Issue date: | 09/08/1998 |
| From: | Clifford J NRC (Affiliation Not Assigned) |
| To: | Ray H SOUTHERN CALIFORNIA EDISON CO. |
| References | |
| TAC-M95861, TAC-M95862, NUDOCS 9809140102 | |
| Download: ML20151V136 (3) | |
Text
.- _.- _.
1 September-8, 1998 l
l Mr. Harold B. Ray Executive Vice President Southern California Edison Company San Onofre Nuclear Generating Stat. ion P. O. Box 128 San Clemente, California 92674-0128 SUBJEC'T:
REQUEST FOR ADDITIONAL INFORMATION RELATED TO REDUCED WATER LEVEL IN THE REFUELING CAVITY (TAC NOS. M95861 AND M95862) l
- Dear Mr. Ray; In a letter dated May 8,1996, Southem California Edison (SCE) subm!tted a request for amendment to the licenses for San Onofre Nuclear Generating Station (SONGS) Units 2 and 3,
- which proposed a reduction in the minimum water level in the refueling cavity during refueling operations, and an extension of the allowed outage time for the shutdown cooling system. In order to complete our review, we request that you provide the additional Information identified in l
the enclosure.
l l
Your timely response would allow us to expeditiously complete this review.
Please contact me at 301-415-1352 if you have any questi,ons.
Sincerely, 1
Original-Signed By' James W. Clifford, Senior Project Manager Project Directorate IV-2 Division ~of Reactor Projects Ill/IV Office of Nuclear Reactor Regulation Dock'et Nos. 50-361 DISTRIBUTION:
and 50-362 Docket File EPeyton l
PUBLIC OGC
Enclosure:
Request for Additional Information PDIV-2 R/F ACRS EAdensam DKirsch, RIV WCFO l
WBateman TPGwynn, RIV cc w/ encl: See next page JClifford WLyon, SRXB DOCUMENT NAME: SO95861.RAI
- Te receive a copy of this document, indicate in the box: "C" = Copy without enclosures "E" = Copy with enclosures "N" = No copy OFFICE PDIV-2/P)d PDIV-2/LA
)
l NAME JClifforff' EPeytonMP:
DATE 09/9 98 09M98 L ; OFFICIAL RECORD COPY 3
(,
I i
9909140102 990909 PDR ADOCK 05000361
{I[
O Mr. Harold B. Ray September 8, 1998 cc w/ encl:
l Mr. R. W. Krieger, Vice President Resident inspector / San Onofre NPS l
Southem California Edison Company c/o U.S. Nuclear Regulatory Commission San Onofre Nuclear Generating Sta'.lon Post Office Box 4329 l
P. O. Box 128 San Clemente, Califomia 92674 San Clemente, Ca'ifomia 92674-0128 Mayor Chairman, Board of Supervisors City of San Clemente County of San Diego 100 Avenida Presidio 1
1600 Pacific Highway, Room 335 San Clemente, California 92672 l
San Diego, California 92101 l
Mr. Dwight E. Nunn, Vice President l
Alan R. Watts, Esq.
Southern Califomia Edison Company Woodruff, Spradlin & Smart San Onofre Nuclear Genertting Station 701 S. Parker St. No. 7000 P.O. Box 128 Orange, Califomia 92668-4702 San Clemente, California 92674-0128 Mr. Sherwin Harris Resource Project Manager
- Public Utilities Department City of Riverside 3900 Main Street Riverside, California 92522 Regional Administrator, Region IV U.S. Nuclear Regulatory Commission Harris Tower & Pavilion 611 Ryan Plaza Drive, Suite 400 Arlingtor,, Texas 76011-8064 1
Mr. Paul Schneringer 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 l.
Sacramento,'Califomia 94234 i
1 i-
e
{
REQUEST FOR ADDITIONAL INFORMATION OPERATION AT REDUCED WATER LEVEL DURING REFUELING OPERATIONS SOUTHERN CALIFORNIA EDISON COMPANY SAN ONOFRR NUCLEAR GENERATING STATION (SONGSL UNITS 2 AND 3 DOCKET NOS. 50-381 AND 50-382 1.
On page 2, it is stated that time to boil curves are provided in Attachment E for 23 feet and 13 feet above the reactor vessel (RV) flange and for one foot below the RV flange.
Attachment E does not provide the minus one foot information. Please provide this curve.
2.
It is also stated on page 2 that the containment can be closed within one hour for any svater level above the RV flange. Please provide the time to boll for water level at the RV flange and, if this is less than one hour, please discuss how containment closure is ensured.
3.
The staff believes that the phrase " containment penetration with direct access to the Outside atmosphere" refers to any opening in the reactor building pressure boundary that provides a direct path from the atmosphere inside the reactor building to outside the reactor building. Please confirm the staff's understanding of this phrase or,ifincorrect.
provide a correct description of the phrase.
4.
- On page 7, it is stated that the risk of inventory boiling and of core damage is stated to be 1.5 x 104/ day and 6 x 104/ day, respectively, when the requested TS change is compared to the current TS requirements. What are the current values (per day)?
What is the benefit of the anticipated outage reduction time on core damage probability during the outage a nd how is overall annual core damage probability affected?
5.
On page 8, it is stated that the time to boll 6 days after shutdown at 23 feet is 4.0 hours0 days <br />0 hours <br />0 weeks <br />0 months <br />, and at 20 feet it is 3.5 hours5.787037e-5 days <br />0.00139 hours <br />8.267196e-6 weeks <br />1.9025e-6 months <br />. These values appear to correspond to an initial temperature of 120'F in Figure 1, but the proposed revision is with respect to a maximum temperature of 140'F. In the revised TS 3.9.4, Action A.4., you retain the previous 4.0 hours0 days <br />0 hours <br />0 weeks <br />0 months <br /> as completion time for containment closure as opposed to a change such as "4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> or within the calculated time to boll, whichever is less." In the revised TS 3.9.5, Action C.3., you also retain the 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> in contrast to a time to boll of 2.3 hours3.472222e-5 days <br />8.333333e-4 hours <br />4.960317e-6 weeks <br />1.1415e-6 months <br /> as stated on page 10 of your submittal. Please clarify the apparent inconsistencies, provide corrections if inconsistencies exist, and either justify retaining the 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> or submit a revision consistent with your calculations. Note this comment applies to multiple locations in the submittal.
6.
Provide the basis for the maximum heatup rate of 2.6'F/hr stated on page 9. If this value is incorrect, please provide the correct value and its basis.