ML20207S186
| ML20207S186 | |
| Person / Time | |
|---|---|
| Site: | North Anna  |
| Issue date: | 03/10/1987 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20207S183 | List: |
| References | |
| NUDOCS 8703190096 | |
| Download: ML20207S186 (2) | |
Text
-
,1 o
UNITED STATES
~,,
8' NUCLEAR REGULATORY COMMISSION c
{
.,E WASHINGTON, D. C. 20555
. /
s P*W SAFETY EVALUATION RY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT NO. 90 v
FACILITY OPERATING LICENSE NO NPF-4 VIRGINIA ELECTRIC AND POWED COMPANY b'
OLD DOMINION ELECTRIC COOPERATIVE NORTH ANNA POWEP STATION, UNIT NO. 1 DOCKET NO.50-33R
, INTRODUCTION Ry letter dated February 6,1986, the Virginia Electric and Power Company (the licensee) proposed changes to the Tect ifcal Specifications (TS) for the North Anna Power Station, Units No. I and No. 2 (NA-l&21 Specifically, the changes I;ertain to Section 3/4.6.3, Table 3.6-1, " Containment Isolation r.
. Valves," for 'the NA-182 TS. The changes reflect a design modification for the installation 'of a new containment isolation valve in the letdown line of NA-1A2.
On April 4,1986, Amendment No. 63 was issued for NA-? which addressed the proposed changes as reauested in the licensee's above noted letter dated February 6, 1986. The safety evaluation supporting Amendment No. 63 addressed the proposed changes for both NA-182.
It was stated in the safety evaluation that an amendment for NA-1 would not be issued until the new NA-1 containment i
istslation valve was installed in the forthcoming cycle 6 refueling outage.
4 Wf th the passage of time, this appropriate NA-1 refuelino outage is now iminent.
I The discussion and evaluation provided below are identical to the previously
/
.ispied safety evaluation supporting Amendment No. 63 for NA '. However, references to NA-2 in the previous safety evaluation have been deleted below.
5 DISCUSSION:
The existing three parallel valves (HCV-1200A, HCV-12008 and HCV-1200C for NA-11 in the letdown line were designated as containment isolation valves inside containment. These valves are located at an elevation that is below the maximum flood IcVel in the containment and, therefore, do not meet the guidelines of t
Regulatory Guide 1.97 concerning environmental qualification. Moreover, these valves have experienced leakage problems relative to meeting the leak' testing I
requirements of Appendix J to 10 CFR Part 50.
The licensee's proposed resolution is to add a new valve in the letdown line for NA-1 that will serve as the containment isolation valve inside centainment. The new valve will be located above the maximum flood level and will meet the design criteria of containment isolation valves. Also, this single valve will provide greater assurance of leakage integrity of the line.
The existing outboard containment isolation valve will remain unchanged.
8703190096 870310 PDR ADOCK 05000338 p
~ The staff finds this design modification acceptable and to be in compliance with Standard Review Plan Sections 6.2.4, " Containment Isolation System," and i
6.2.6, " Containment Leakage Testing."
In conjunction with the above design modification, the ifcensee has proposed to change the TS Table 3.6-1, " Containment Isolation Valves," to reflect the change. The containment isolation function of the valve (TV 1204A for NA-1) negates this function previously assigned to the following valves in the letdown line: the three parallel valves identified above, a relief valve (RV-1203 for NA-1), and a manual valve (HCV-1142 for NA-1). The relief valve discharges to the pressurizer relief tank, and the manual valve is in a line which connects the letdown line to the Reactor Heat Removal heat exchanger.
The existing valves will not be physically removed but will no longer provide a containment isolation function.
EVALUATION Based on the above, the staff finds the proposed changes to appropriately meet the provisions for the containment isolation letdown line and, therefore, finds the change to be acceptable.
I ENVIRONMENTAL CONSIDERATION This amendment involves a change in the installation or use of a facility component located within the restricted area as defined in 10 CFR Part '0.
The staff has determined that the amendment involves no significant increase in the amounts, and no significant change in the types, of any effluents that may be released offsite, and that there is no significant increase in individual or cumulative occupational radiation exposure. The Comission has previously published a proposed finding that the amendment involves no significant hazards consideration and there has been no public comment on such finding. Accordingly, the amendment meets the eligibility criteria for categorical exclusion set forth in 10 CFR 551.22(c)(9).
Pursuant tt.10 CFR 951.22(b), no environmental impact statement or environmental assessment need be prepared in connection with the issuance of the amendment.
CONCLUSION We have concluded, based on the considerations discussed above, that (1) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, and (2) such activities will be conducted in compliance with the Commission's regulations, and the issuance of the amendment will not be inimical to the common defense and security or to the health and safety of the public.
l Date: March 10, 1987 Principal Contributors:
C. Li L. Engle
- - _ _ _ _ _ _ _ - _ _ _ _ _ _ _ _ _ _