ML20052E051
| ML20052E051 | |
| Person / Time | |
|---|---|
| Site: | Surry  |
| Issue date: | 04/27/1982 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20052E048 | List: |
| References | |
| NUDOCS 8205100042 | |
| Download: ML20052E051 (4) | |
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SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT NO. 77 TO FACILITY OPERATING LICENSE NO. DPR-32 j
AND AMENDMENT NO. 78 TO FACILITY OPERATING LICENSE NO. DPR-37 j
VIRGINIA ELECTRIC AND POWER COMPANY SURRY POWER STATION, UNIT NOS. 1 AND 2 I
DOCKET NOS. 50-280 AND 50-281 Introduction By letters dated December 28, 1979, and February 26, 1980, the Virginia Electric and Power Company (the licensee). requested amendments to License Nos. DPR-32 and DPR-37 for the Surry Power Station, Unit Nos. I and 2.
The changes would revise the Technical Specifications related to the Auxiliary Feedwater System.
The two applications were supplemented by the following letters:
November 19, 1979 January 10, 1980 February 1,1980 March 21,1980 May la,1980 September 30, 1980 October 5,1980 October 17, 1980 December 12, 1980 December 23, 1980 December 26, 1980 April 20,1981 September 14, 1981 November 9,1981 Discussion and Evaluation On November 17, 1980, the NRC issued a Safety Evaluation Report of the Auxiliary Feedwater (AFW) System Reliability for Surry 1 and 2.
This evaluation provided the background for the review and closed several aspects of the review. However, several aspects of the review were left open for further information or evaluation. The open items were:
8205100042 820427 PDR ADOCK 05000280 P
. 1.
Recommendation GS-1: Technical Specifications were required to limit the time that one AFW system pump and its associated flow train and essential instrumentation can Se inoperable. The Technical Specifications proposed by the licensee on December 28, 1979, provided that three pumps be restored to operable status within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> or be in hot shutdown within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />. These requirements are consistent with the Standard Technical Specifications and we find them acceptable.
2.
Recommendation GS-6: Technical Specifications were required which would verify by a flow test the normal flow path for the primary AFW system water source to the steam generators. This change to the Technical Specifications has been proposed and based on our review, we find this change acceptable.
3.
Additional Short Term Recommendation 3: The licensee should implement the following requirements as specified by Item 2.1.7.b on page A-32 of NUREG-0578:
" Safety-grade indication of auxiliary feedwater flow to each steam generator shall be provided in the control room."
This item was resolved by NRC "05000280/LER-1981-026-03, /03L-0:on 810709,during Startup,Max Allowable Containment Partial Pressure Was Exceeded.Caused by Feedwater Leak Through Failed Flange Gasket for [[system" contains a listed "[" character as part of the property label and has therefore been classified as invalid. Line Flow Limiting Venturi.Gaskets Replaced|letter dated August 7,1981]].
4.
Recommendation GL-3: At least one AFW system pump and its associated flow path and essential instrumentation should automatically initiate AFW system flow and be capable of being operated independently of any alternating current power source for at least two hours. Conversion of direct current power to alternating current is acceptable.
By letter dated December 9,1981, the licensee stated that at least one l
AFW system pump and flow path is automatically initiated upon a loss of all AC power. Remote on-off operation from the control room is provided to control flow. We consider the licensee's response acceptable.
5.
Recommendation GL-5: The licensee should upgrade the AFW system automatic initiation signals and circuits to meet safety-grade requirements.
This item was resolved by NRC "05000280/LER-1981-026-03, /03L-0:on 810709,during Startup,Max Allowable Containment Partial Pressure Was Exceeded.Caused by Feedwater Leak Through Failed Flange Gasket for [[system" contains a listed "[" character as part of the property label and has therefore been classified as invalid. Line Flow Limiting Venturi.Gaskets Replaced|letter dated August 7,1981]].
6.
NRC Recommendation - The AFWS flow control valves for both the motor and turbine pump trains are AC powered, normally open, fail-as-is motor operated valves which are located inside containment. Also, manual
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normally open valves ere located inside containment. The AFWS design should be reevaluated, including the possibility of relocating the valves outside containment, assuming an accident inside containment which l
necessitates AFWS operation and which creates a containment environment
(. humidity, radiation} that precludes access to the valves. The l
reevaluation should consider the following:
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3-A possible common mode failure (environmentally induced) causing a.
spurious closure or failure of the NOVs in a throttled position.
b.
An AFWS line break downstream of the MOVs and failure of the MOVs to operate.
By letter dated December 9,1981, the licensee stated that the AFW system flow control valves for both the motor and turbine driven pumps will remain instde containment. The valves and operators currently installed do not have documentation to substantiate their environmental quali fica tion. However, the licensee has committed to obtain the required documentation. Valve operato'rs which cannot be qualified will be replaced by qualified valves.
We consider the licensee's response acceptable.
7.
Basis for AFW System Flow Requirements The licensee should provide a commitment date for responding to the information requested in Enclosure 2 of the NRC letter dated September 25, 1979.
By letter dated December 26, 1980, the licensee verified that the mini.aum flow rate requirement of 500 gpm by the auxiliary feedwater system could Se maintained under the following transient conditions:
1.
Loss of normal feedwater transient a.
With offsite power available b.
Concurrent with loss of offsite power 2.
Rupture of a main steam line 3.
Loss of all AC power 4.
Loss of Coolant Accident (LOCA) 5.
Cooldown During our review, it was noted that the licensee's analysis did not evaluate the case for a feedwater line Break - an event that is often considered limiting. The licensee was requested to verify that the required AFW flow could be provired for this event. Their response dated November 9,1981 indicated that the flow requirement for a feedwater line break is much less than that required for the design basis loss of normal feedwater transient (i.e., 350 gpm vs 500 gpml.
l Based on our review of the licensee's submittals, we conclude that sufficient AFW flow can be delivered to two steam generators by the AFW system to meet the minimum Heat removal requirements following any design basis transient or accident assuming the worst case single active failure.
The NRC Safety Evaluation Report dated September 19, 1979, evaluated the fire protection program and concluded that the existing cross' connect between the two Units' auxiliary feedwater systems was an acceptable means for providing auxiliary feedwater from one unit to the other if the AFW pumps in one unit were destroyed by fire. The Technical Specifications proposed by letter dated February 26, 1980, provided this requirement. We have reviewed the proposed Technical Specifications and find them accepta61e.
Environmental Consideration We have determined that the anendments do not authorize a change in effluent types or total amounts nor an increase in power level and will not result in any significant environmental impact. Having made this determination, we have further concluded that the amendments involve an action which is insignificant from the standpoint of environmental impact and, cursuant to 10 CFR 51.5(d)(4), that an environmental impact statement or negative declaration and environ-mental impact appraisal need not be prepared in connection with the issuance of these amendments.
Conclusion We have concluded, based on the considerations discussed above, that:
(1) because the amendments do not involve a significant increase in the probability or consequences of accidents previously considered and do not involve a significant decrease in a safety margin, the amendments do not involve a significant hazards consideration, (2) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, and (3) such activities will be conducted in compliance with the Comnission's regulations and the issuance of these amendments will not be inimical to the common defense and security or to the health and safety of the public.
Date:
April 27,1982
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