ML18053A339

Forwards Revised Amend Request for License DPR-20 Re Primary Coolant Gas Vent Sys.Rev Incorporates Changes Resulting from NRC Review of 830830 Submittal & Is Consistent W/Generic Ltr 83-37,NUREG-0737 Tech Specs

ML18053A339
Person / Time
Site:	Palisades
Issue date:	04/21/1988
From:	Berry K CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.)
To:	NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM)
Shared Package
ML18053A340	List: ML18053A339 ML18053A342
References
RTR-NUREG-0737, RTR-NUREG-737 GL-83-37, TAC-M54405, NUDOCS 8804270204
Download: ML18053A339 (6)

Text

consumers Power Kenneth W Berry POWERiNii Director llllCHlliAN'S l'ROliRESS Nuclear Licensing General Offices: 1945 West Parnell Road, Jackson, Ml 49201 * (517) 788-1636 April 21, 1988 Nuclear Regulatory Commission Document Control Desk Washington, DC 20555 DOCKET 50-255 - LICENSE DPR PALISADES PLANT -

TECHNICAL SPECIFICATIONS CHANGE REQUEST - PRIMARY COOLANT GAS VENT SYSTEM - REVISION (TAC NO. M54405)

Consumers Power Company originally submitted a Technical Specifications Change Request (TSCR) on the Primary Coolant Gas Vent System (PCGVS) on August 30, 1982. This TSCR revision incorporates changes that resulted from NRC staff review of the August 30, 1982 submittal and is consistent with the intent of Generic Letter 83-37, NUREG-0737 Technical Specifications. Differences with GL 83-37 are the surveillance interval and Limiting Conditions for Operation due in part to the specific Palisades Plant design.

The Palisades PCGVS is described in FSAR Sections 4.8 and 7.4.2.2.2. In summary, the PCGVS consists of a line from the reactor vessel head and a line from the pressurizer connected to two parallel sets of valves for each vent line. Downstream of the parallel sets of valves the paths connect in a common header. The header then divides into two vent paths through another set of parallel valves; one to the containment building and one to the quench tank. A vent path therefore exists from either the reactor vessel head or pressurizer to either the containment or quench tank. These paths are designed with double isolation and are single-failure proof.

The revision in the TSCR, which replaces the August 30, 1982 submittal in its entirety, takes advantage of both the available vent paths, whereas the earlier TSCR only provided requirements for the vent path to. containment.

This change also incorporates the 72-hour action statement which is consistent with the NUREG-0737 Technical Specifications.

OC0488-0101-NL04 r-aa642762o4 880421 ~II I.

.i PDR ADOCK 05000255 i . I 1 P. *oco I i __ _

Nuclear Regulatory Commission 2 Palisades Plant TSCR Revision - PCGVS

.,April 21, 1988 Our August 30, 1982 submittal enclosed a check for $4,000.00, therefore, no application fee is provided herewith. We request the previous payment be applied to this submittal. We note that the earlier ,Consumers Power Company change request preceded the issuance of Generic Letter 83-37 wherein the changes propos~d in this revised TSCR became necessary.*

Kenneth W Berry ,

Director, Nuclear Licensing CC Administrator, Region III, NRC NRC Resident Inspector - Palisades Attachments OC0488-0101-NL04

1 CONSuMERS POWER COMPANY Docket 50-255 Request for Change to the Technical Specifications License DPR-20 For the reasons hereinafter set forth, it is requested that the Technical Specifications contained in the Provisional Operating License DPR-20, Docket 50-255, issued to Consumers Power Company on October 16, 1972, for the Palisades Plant be changed as described in Section I below:

I. Changes A. Add new specification 3.1.9 (see page changes)

B. Add new'part 14 to Table 4.2.2 (see page changes)

II. Discussion The above proposed Technical Specifications changes are requested to comply with the Technical Specification requirement of NUREG-0737, Item II.B.1 and Generic Letter 83-37. These changes provide limiting conditions for operating and surveillance requirement for the Primary Coolant Gas Vent System (PCGVS).

The PCGVS is designed to relieve steam or noncondensible gases in the reactor vessel head and pressurizer areas of the Primary Coolant System. The system consists of a flow-limiting orifice on both the reactor vessel vent and pressurizer vent line, solenoid valves, a pressure transmitter for pressure indication and alarm, and connected piping. The orifices are placed as close to the vessels as possible to limit the possibility of an uncontrolled Loss of Coolant Accident.

They are sized so.that they would limit mass loss from a line break to less than the makeup capability of a single charging pump to maintain pressurizer level control.

A parallel set of solenoid valves on each the reactor vessel and pressurizer vent lines are connected to a common vent header which can discharge steam or gas to either the containment or the pressurizer quench tank.

The solenoid vent isolation valves (six total are remotely controlled in the control room) a~e series redundant with Class lE controls and power including a separate key-operated control switch for each valve to ensure the primary coolant boundaries are maintained. The vent isolation valves are also parallel redundant to reduce the probability of a vent path failing to open since the valves fail-close on loss of power.

OC0488-0101-NL04

2 The entire PCGVS is designed for Seismic Category I. The piping and supports meet ASME B&PV Code Section III requirements.

The proposed change A to the Limiting Conditions for Operation for the PCGVS differ somewhat from the Standard Technical Specifications due to the specific Palisades design which has vent paths from the reactor vessel head and pressurizer. These two locations are the high points in the primary coolant system.

The vents from either the reactor vessel or pressurizer can be aligned directly to the containment or to the pressurizer quench tank. The applicable modes of operation are consistent with the STS, however, they are changed to be consistent with the Palisades Specifications.

The action statements are revised to reflect the Palisades specific PCGVS. Instead of allowing one of three vent paths to be inoperable like the STS, the Palisades proposal (for action statement a) maintains a vent path from both the reactor vessel and pressurizer to either the containment or quench tank. Like the STS, two vent paths are operable allowing 30 days for repair of one path. For .action statement b, if either the reactor vessel, pressurizer or both vent paths are inoperable, then 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> is allowed to restore the inoperable flow paths.

The STS action statements specify that power is to be removed from the valve actuator of all the valves in the inoperable flow path. We have proposed that only the inoperable valves be electrically locked closed with their keys removed. The locked closed position effectively removes power from the valve actuator. The removal of the key, with the position switch in the locked closed position, provides a second level administrative control over inadvertent opening_. The locked closed position is also the normal operating position for the vent isoiation valves. If other valves in the flow paths were to have their power r~moved at the breaker, rather than at their hand switches, it would reduce the system redundancy by further reducing the number of valves operable and available in the operable vent paths. Position indication would also be lost. This is because the flow paths are parallel redundant with each valve in a redundant flow path powered by the same 125V DC panel breaker.

Proposed change B*provides surveillance requirements that are the same as those in the STS, except the surveillance interval has been changed from 18 months to each refueling cycle. The refueling cycle interval is consistent with other Palisades' surveillance requirements for other equipment in Table 4.2.2. Normally, operating cycles at Palisades are scheduled for 12 to 15 months, but are dependent upon plant availability during the cycle. Therefore, the change in wording from 18 months to refueling for the surveillance requirement would, normally, have no effect on the completion interval. For those OC0488-0101-NL04

3 refueling cycles exceeding 18 months, a significant amount of plant outage time would have to occur. During outages with the plant in cold shutdown, the PCGVS is not required to be operable. If, during an outage, maintenance on the reactor head or pressurizer involves the vent lines, returning of the system to service would typically involve demonstrating operability by conducting the Technical Specifications Surveillance on the affected components. The operability of the system would then be assured. If no maintenance were to occur affecting the PCGVS, then the operability of the system should not be in question.

Analysis of No Significant Hazards Consideration The probability of occurrence of an accident has not been increased.

The system restricting orifices were placed as close to the reactor vessel and pressurizer as possible to limit the possibility of an uncontrolled Loss of Coolant Accident. The orifices are sized so that they would limit the mass loss from a line break to less than the makeup capability of a single charging pump to maintain pressurizer level control. Double isolation valves are maintained as required for PCS boundary valves. The consequences of an accident are not increased as the LOCA event has already been analyzed for a full spectrum of break sizes larger than the pot~ntial break size that exists in the PCGVS. Furthermore, system redundancy ensures the system design requirements are met so that the PCGVS will relieve steam or gases and the proposed Technical Specifications ensure operability of the system.

The probability of occurrence of a malfunction of equipment also has not been increased. The added valves are maintained in the closed position when above cold shutdown are series redundant and fail closed on loss of power. The consequences of a malfunction of equipment are no greater than those already analyzed in the FSAR.

The proposed Technical Specifications ensure system operability and plant limiting condition for operation are met so that there is no increase in the probability of occurrence or consequences of an accident or malfunction of equipment described in the FSAR.

III. Conclusion The Palisades Plant Review Connnittee has reviewed this Technical Specification Change Request and has determined that this change does not-involve an unreviewed safety question and, therefore, involves no OC0488-0101-NL04

[) ..

4 significant hazards consideration. This change has also been reviewed under the cognizance of the Nuclear Safety Board. A copy of this Technical Specification Change Request has been sent to the State of Michigan official designated to receive such Amendments to the Operating License.

CONSUMERS POWER COMPANY ByDa~~f:~Nuclear Operations Sworn and subscribed to before me this 21st day of April 1988.

~&~~

Elaine E Buehrer,/NOtary Public Jackson County, Michigan My commission expires October 31, 1989 OC0488-0101-NL04