ML17262A492
| ML17262A492 | |
| Person / Time | |
|---|---|
| Site: | Ginna  |
| Issue date: | 06/03/1991 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML17262A491 | List: |
| References | |
| NUDOCS 9106050018 | |
| Download: ML17262A492 (6) | |
Text
UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON. D.C. 20555 SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION SUPPORTING AMENDMENT NO.
42 TO FACILITY OPERATING LICENSE NO. DPR-18 ROCHESTER GAS AND ELECTRIC CORPORATION R. E.
GINNA I'lUCLEAR POWER PLANT DOCKET HO. 50-244
1.0 INTRODUCTION
By letter dated February 15,
- 1991, the Rochester Gas and Electric Corporation (RGSE) (the licensee) reouested an amendment to Facility Operating License No.
DPR-18 to change the Technical Specification for the Ginna Nuclear Power Plant as set forth in Appendix A to that license.
The proposed amendment would revise the Technical Specification 3.3.1.1g to reflect a plant modification that is being prepared to enable the operation, from the control room, of Motor Operated Valve MOV-856 which is the refueling water storage tank (RWST) delivery valve.
This modification involves the installation of a key-operated-switch in the control room that will remove and lock open the 125 VOC control power to the valve actuator.
The same method was approved for MOV-896A and B, the RWST outlet valves in the HRC SER to Amendment 7 of the R. E. Ginna Provisional Operating
- License, dated May 14, 1975.
2.0 EVALUATION MOV-856 must be in the open position during the injection phase of a loss of coolant accident (LOCA) when the reactor coolant system (RCS) temperature is at or above 350'F.
This is to ensure that water can be immediately delivered from the RWST to the reactor vessel upon initiation of a Safety Injection (SI) signal.
- However, MOV-856 must be closed for two other conditions:
(1) for the recirculation phase of a LOCA, and (2) when the reactor is shutdown with the Residual Heat Removal (RHR) System in operation.
The current Technical Specification of R.
E. Ginna requires the removal of AC power from the valve motor when the RCS temperature is at or above 350'F to prevent inadvertent or spurious closure.
This is ensured by locking open the breaker which provides 480 VAC power to the valve motor, but the disadvantage of this method is that the close function of MOV-856 cannot be performed completely from the control room.
An entry must first be made into the controlled auxiliary building to unlock and close the breaker to restore the AC power to the valve.
In the event of a LOCA, the Post LOCA Emergency Procedures require that, when the RWST level reaches 28Ã,
RHR pumps are stopped and valves realigned so that the suction source of water for the RHR pumps is switched from the RWST (by closing MOV-856) to containment sump "B".
This switchover procedure is initiated to isolate the RWST from any potentially high radioactive source of water in containment sump "B" released
<rom the RCS following a LOCA.
(
9i060500iS 9i0603 PDR ADOCK 05000244 P
PDR The Post LOCA Emergency Procedures also require the RHR pump to be started following valve realignment but not before RLIST level has further decreased to 15Ã to ensure adequate RHR pump NPSH.
In the limiting case of a large break LOCA, an estimated time for the RMST level to decrease from 28% to 15K could be on the order of 10 minutes.
Consequently, time is limited for personnel to restore power to the valve with the present valve control configuration as mentioned above.
The new proposed configuration would install a key-operated-switch in thE control room to remove and lock open the 125 VDC control power to the valve actuator.
By requiring the actuation of the key-operated-switch in conjunction with the existing AC power control switch, the proposed modification will maintain the existing assurance of proper valve alignment.
In addition, the elimination of entry into the auxiliary building during a
LOCA will reduce the risk of radiological hazards to personnel.
In the NRC SER to Amendment 7 of the R.
E. Ginna Provisional Operating License, dated May 14, 1975, the staff stated that locking out of A.C. power to motor operated valves was an acceptable procedure to design against a single failure that could cause an undesirable component action and result in a loss of capability to perform an intended safety function.
Branch Technical Position ELESC 18, in Appendix 7A of the Standard Review Plan is to be applied to each of the "active," manually controlled electrically operated valves that are required to operate during various safety system operational sequences.
In addition, the capability of the proposed configuration to withstand the effects of a seismic or fire event is not decreased, because the key switch installation will be qualified to meet the standards set forth by IEEE Std. 383-1974, Vertical Flame Test Requirements.
Additional circuitry will not be installed in any plant area's which do not already contain t10V-856 power and control circuitry.
Therefore, 10CFR50 Appendix R analyses will remain unchanged.
Based on the staff's review, we find that the licensee's proposed modification will improve the safe operation of the plant especially when time is critical for the switchover of valve position during a large break LOCA.
Me also find that this same modification method for NOV-896A and B was reviewed for its operational safety and approved in the NRC SER to Amendment 7 of the R. E. Ginna Provisional Operating License dated Hay 14, 1975.
Therefore, we conclude that the licensee's proposed modification for HOV-856 is acceptable.
3.0 STATE CONSULTATION
In accordance with the Commission's regulations, the State of New York State official was notified of the proposed issuance of the amendment.
The State official had no comments.
4.0 ENVIRONMENTAL CONSIOERATION 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 20.
The NRC 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 Commission has previously published a proposed finding that the amendment involves no significant hazards consideration, and there has been no public comment on such finding (56 FR 20045).
Accordingly, this amendment meets the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9).
Pursuant to 10 CFR 51.22(b) no environmental impact state-ment or environmental assessment need be prepared in connection with the issuance of this amendment.
- 5. 0 CONCLUSION The Commission has 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, (2) such activities will be conducted in compliance with the Commission's regulations, and (3) the issuance of the amendment will not be inimical to the common defense and security or to the health and safety of the public.
Principal Contributor:
A. Chu Date:
June 3, 1991
l I
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4 fp C t
UNITED STATES NUCLEAR REGULATORY COIVlMISSION WASHINGTON, D.C. 20555
'June',.3, 1991 Docket Ho. 50-244 Dr. Robert C. Mecredy Vice President, Huclear Production Rochester Gas It Electric Corporation 89 East Avenue Rochester, New York 14649
Dear Dr. Mecredy:
SUBJECT:
ISSUANCE OF AMENDMENT HO. 42 TO FACILITY OPERATING LICENSE NO.
DPR R.E.
GIHNA NUCLEAR POWER PLANT (TAC NO. 79829)
The Commission has issued the enclosed Amendment Ho. 42 to Facility Operating License No.
DPR-18 for the R.
E. Ginna Nuclear Power Plant.
This amendment is in response to your application dated February 15, 1991.
This amendment revises the requirements of the Technical Specifications to modify the method of locking valve 856 open from removal of A.C. power to removal of D.C. control power in order to enable valve manipulation from the control room while maintaining the locked OPEN requirement.
A copy of our Safety Evaluation is also enclosed.
Notice of Issuance will be included in the Commission's biweekly Federal
~Re ister notice.
Sincerely,
Enclosures:
1.
Amendment No. 42 to License No.
DPR-18 2.
Safety Evaluation cc w/enclosures:
See next page Al en R. Johnson, Project Manager P oject Direct ate I-3 Div'actor Projects
- I/II Office of Nuclear Reactor Regulation