2CAN099303, Documents Position Re Unit 2 TS 4.5.2.g.1.Util Will Submit TS Change Request Providing More Forward Wording If ECCS Section of Unit 2 TS Similar to Restructured STS within 60 Days of Ltr Date

Documents Position Re Unit 2 TS 4.5.2.g.1.Util Will Submit TS Change Request Providing More Forward Wording If ECCS Section of Unit 2 TS Similar to Restructured STS within 60 Days of Ltr Date

ML20057C730
Person / Time
Site:	Arkansas Nuclear
Issue date:	09/21/1993
From:	King R ENTERGY OPERATIONS, INC.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
2CAN099303, 2CAN99303, NUDOCS 9309290310
Download: ML20057C730 (3)

Text

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v ler Entergy Operations,Inc.

Rcue 3. D:n 137G OperatlOnS Rese e id 501-964-3100 September 21,1993 2CAN099303 ..

U. S. Nuclear Regulatory Commission Document Control Desk Mail Station Pl-137 Washington, DC 20555

)

Subject:

Arkansas Nuclear One = t 9t 2 Docket No. 50-368 License No. NPF-6 -l ANO Position Regarding Technical Specification _4.5.2.g ]

l Gentlemen: i l

This submittal documents . Arkansas Nuclear One's (ANO's) position regarding of ANO-2 l Technical Specification 4.5.2.g.1 as previously discussed with members of the NRC staff.

This specification stipulates that the correct position of each electrical and/or mechanical

, position stop for the High Pressure Safety Injection (HPSI) and Low Pressure Safety I Injection (LPSI) throttle valves be verified "within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> following completion of each l valve stroking operation." The bases for Technical Specification 4.5.2 defines the intent j of the specification by stating " surveillance requirements of throttle valve position stops  :

and flow balance testing provide assurance that proper ECCS flows will be maintained in the event of a LOCA."

The ECCS throttle valves are normally closed, motor-operated valves that have a safety function to open to allow flow of safety injection into the Reactor Coolant System. The valves have electrical position stops (limit switches) which are set to obtain the required flow distribution for high or low pressure safety injection following a LOCA. To implement Technical Specification 4.5.2.g.1, ANO requires that the position stops for any of the subject throttle valves be verified following any evolutions that could potentially affect or alter the valve's position stop setting. Typical evolutions that would require position stop verification include valve or actuator maintenance or modification, calibration and stroking the valve to its calibrated full open position.

Throttle valve movement operations less than that which would encounter the position stops are not considered by ANO to be a condition which would alter the ability of the throttle valves to achieve their preset opening position if a LOCA were to occur. A recent ANO-2 action where less than full valve stroking ivould be applicable is the current l refilling of the "A" Safety Injection Tank (SIT).

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U.S.NRC September 21,1993

- 2CAN099303 Page 2 Pre'viously identified minor leakage has been occurring through check valves and the 2CV-5016-2 throttle valve whereby the SIT requires periodic refilling to maintain required  !

safety injection tank water level. Filling of the tank is accomplished through either 2CV-5015-1 or 2CV-5016-2 which are ECCS injection valves identified under Technical l Specification section 4.5.2.g.2. In addition, all SITS require refilling periodically during normal plant operation as a result of monthly sampling activities.

The movement of these valves to refill the SIT is considered a " bumping" operation in that the valve is only moved 6 to 10% ofits full stroke position. This valve movement is well below the contact point for the position stops on the ECCS throttle valves which are typically set at about 80% of full stroke capability. Therefore, valve bumping or movement of a similar nature for any of the subject ECCS throttle valves should not have l any effect on the valves position stops or on system performance. Bumping of the valves in this manner is allowed by ANO-2 procedures, but is not typically performed except under certain identified conditions.

Backleakage from the "A" SIT is currently approximately 16 gallons / day. Backflow of i this magnitude is insuflicient to cause damage to system valves considering their rugged stainless steel construction. In addition, the backleakage from the SIT is significantly less than that allowed by the ANO-2 Technical Specifications for leakage from the Reactor Coolant System through the HPS1 system valves. Technical Specifications state that RCS leakage rates into the HPSI system equal to or less than I gpm are acceptable and that leak rates less than or equal to 5 gpm are also acceptable if the latest measured leakrate does not exceed the measured rate of the previous test by an amount that reduces the margin between measured leakrate and the maximum permissible rate (5 gpm) by 50 percent or greater.

The leakage from the "A" SIT is an ANO previously identified condition which has been in our planned work scope for valve repair or replacement. Leakage from the SIT was previously estimated to be as high as 130 gallons / day. Potentialleaking valves in question include 2SI-13A, 2CV-5016-2, 2PSV-5110 and 2SI-10C. The first three valves are l

currently scheduled for repair or replacement during 2R10. Check valve 2SI-10C was

replaced on August 30,1993 and was shown to be a significant contributor to the total system leakage. Leakage was significantly reduced after this valve was replaced and is currently approximately 16 gallons / day.

Generic Letter 89-10 states that limit switch surveillance frequencies measured in years are acceptable providing no specific plant or industry failure history exists to justify otherwise.

Since no known industry failure history or plant specific failure data exists to indicate that position stop repeatability is a problem, ANO believes that its procedures and practices with respect to suncillance of the HPSI and LPSI throttle valves is adequate to ensure that proper ECCS flows will be maintained.

l l U. S. NRC

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. September 21,1993

. 2CAN099303 Page 3 8

Bas'ed on the above discussion, ANO believes that its position on Technical Specification 4.5.2.g is consistent with the intent of the specification as stated in the Bases. Therefore, the current actions being performed by ANO-2 to refill the SIT on a periodic basis or other similar ECCS valve movement operations less than full stroke are not considered by Entergy Operations to be a condition where the surveillance requirements of ANO-2 )

Specification 4.5.2.g would be imposed.

Entergy Operations will submit a Technical Specification Change Request to provide a more straight fonvard wording of the ECCS section of the ANO-2 Technical l Specifications similar to the Restructured Standard Technical Specifications within 60 days of this letter.

Very truly yours, 4  !

J Rick J. King Acting Director, Licensing l

JJF/jt 1

cc: Mr. James L. Milhoan l Regional Administrator U. S. Nuclear Regulatory Commission Region IV 611 Ryan Plaza Drive, Suite 400 Arlington, TX 76011-5064 NRC Senior Resident Inse.; tor Arkansas Nuclear One - ANO-1 & 2 Number 1, Nuclear Plant Road Russellville, AR 72801 Mr. Roby B. Bevan, Jr.

l NRR Project Manager Region IV/ANO-1 l

U. S. Nuclear Regulatory Commission NRR Mail Stop 13-H-3 One White Flint North 11555 Rocksille Pike l Rockville, MD 20852 Mr. Thomas W. Alexion NRR Project Manager, Region IV/ANO-2 U. S. Nuclear Regulatory Commission NRR Mail Stop 13-H-3 One White Flint North

, 11555 Rockville Pike

! Rockville, MD 20852 i-