ML20234B178

Safety Evaluation Supporting Amend 100 to License DPR-36

ML20234B178
Person / Time
Site:	Maine Yankee
Issue date:	06/25/1987
From:	Office of Nuclear Reactor Regulation
To:
Shared Package
ML20234B144	List: ML20234B141 ML20234B169 ML20234B178
References
GL-83-37, NUDOCS 8707020263
Download: ML20234B178 (3)

Text

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SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATING O AMENDMENT NO.100 TO FACILITY OPERATING LICENSE NO. DPR-36 MAINE YANKEE ATOMIC POWER COMPANY (MYAPCo)

MAINE YANKEE ATOMIC POWER STATION (MYAPS)

DOCKET NO. 50-309 1NE0 DUCTION By letter dated March 13, 1985, MYAPCo submitted a request for changes to the Technical Specifications for MYAPS. This submittal was cmplified by further correspondence dated January 15, 1986, which provided information relative to significant hazards considerations; and January 13, 1987, which revised the originally proposed action statement.

The requested Technical Specifications changes would revise Technical Speci-fication 3.3 (Reactor Coolant System Operational Components) adding Section D (Reactor Coolant System Emergency Vent System); add bases for this system; and revised Technical Specification 4.6 (Periodic Testing) adding Specification E (Reactor Coolant System Emergency Vent System) to conform with guidance en-closed in Generic Letter 83-37.

Discussion and Evaluation ,

The following staff guidance concerning Reactor Coolant System Vents (ll.B.1) was put forth in Generic Letter 83-37:

At least one reactor coc.lant system vent path (consisting of at least two ,

valves in series which are powered from emergency buses) shall be operable and closed at all times (except for cold shutdown and refueling) at each of the followiong locations:

1. Reactor Vessel Head

2. Pressurizer steam space

3. Reactor coolant system high point For the plants using a power operated relief valve (PORV) as a reactor coolant system vent, the block valve is not required to be closed if the PORY is operable.

MYAPS Technical Specifications do not currently address the Reactor Coolant System Vent System as required by Generic Letter 83-37. The licensee has proposed to add the requirement that at least one reactor coolant system vent path to be operable at all times (except cold shutdown and refuelinal with motor operated valves shut and power removed since, at MYAPS, PORVs are used as reactor coolant system vents.

8707020263 870625 PDR ADOCK 05000309 P PDR

The' following remedial _ actions are reouired in Generic Letter 83-37 if _ one or more of the reactor coolant system vents is inoperable:

1. With one of the above reactor coolant system vent paths inoperable, STARTUP and/or POWER OPERATION may continue provided the inoperable vent path is maintained closed with power removed from the valve actuator of all the valves in the inoperable vent path; restore the inoperable vent path to OPERABLE status within 30 days, er, be in HOT STANDBY within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in COLD SHUTDOWN within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />.

P. With two or more of.the above reactor coolant system vent paths inoperable; maintain the inoperable vent path closed with power renoved from the valve actuators of all the valves in the inoperable vent paths, and restore at least (twol of the vent paths to OPERABLE status within 72 hnurs or be in HOT STANDBY within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in COLD SHUTDOWN within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />.

The. licensee has proposed the following remedial actions:

1. With one RCS emergency vent path inoperable, ensure that a PORY is operable providing a redundant vent path, and provide a report to the Commission within 30 days describing the cause and nature of the problem and schedule for repair of the inoperable emergency vent path.

2. With both of the RCS energency vent paths inoperable, ensure that one PORY venting path is' operable, and restore at least one RCS emergency vent path to operable within 30 days, or, be in cold shutdown condition within the following 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br />.

The following periodic testing is required by Generic Letter 83-37:

Each reactor coolant system vent path shall be demonstrated OPERABLE at least once per 18 months by:

1. Verifying all manual isolation valves in each vent path are locked in the open position.

2. Cycling each valve in the vent path through at least one complete cycle of full travel from the control room during COLD SHUTDOWN or REFUELING.

3. Verifying flow through the reactor coolant vent system vent paths during venting during COLD SHUTDOWN or REFUELING.

Since MYAPS is a p16nt using PORV as a vent path, the PORV block valve is not required to be closed, thus requirement 1, above, is not applicable to MYAPS.

The licensee has proposed that at least once each refueling interval during cold shutdown condition (1) all remotely operated valves shall be cycled, and (2) flow through each vent path shall be verified.

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The staff has evaluated the proposed changes to the Technical Specifications L and concludes that these changes would impose operability and surveillance I requirements in general conformance with the staff's guidance in Generic Letter 83-37. Further, these changes would not increase the likelihood of a malfunction of safety-related equipment or increase the consequences of an accident previously analyzed or create the possibility of a malfunction different from those previously evaluated. Therefore, the licensee's 1 requested changes are acceptable. '

ENVIRONMENTAL CONSIDERATION This amendnent 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 staff has determined that the amendnent 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 occurational radiation exposure. The Commission has previously issued a proposed finding that this emendment involves no significant hazards consideration and there has been no public comment on such finding. Accordingly, this amendnent 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 statement or environmental assessment need be prepared in connection with the issuance of this 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.

Date: June 25, 1937 Principal Contributor: David Limroth