ML19305B857

Discusses Review of High Pressure Primary Coolant Piping Sys.Event 5 Valve Configuration Does Not Exist at Facility. No Mods or Changes to Inservice Insp & Test Program & Procedures Necessary to Increase Valve Reliability

ML19305B857
Person / Time
Site:	Vermont Yankee File:NorthStar Vermont Yankee icon.png
Issue date:	03/14/1980
From:	Vandenburgh D VERMONT YANKEE NUCLEAR POWER CORP.
To:	Eisenhut D Office of Nuclear Reactor Regulation
References
WVY-80-41, NUDOCS 8003200493
Download: ML19305B857 (2)

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VERMONT YAN KEE NUCLEAR POWER CORPOR ATION SEVENTY SEVEN GROVE STREET B.3.2.1 RUTLAND, VERMONT 05701 WVY 80-41 REPLY TO:

ENGINEERING OFFICE TURNPIKE RO AD WESTBORO. M ASS ACHUSETTS 01581 TELEPHONE s t ? 3se-go t t March 14,1980 United States Nuclear Regulatory Commission Washington, DC 20555 Attention: Of fice of Nuclear Reactor Regul ation Darrell G. Eisenhut, Acting Director Division of Operating Reactors

References:

(a) License No. DPR-28 (Docket No. 50-271)

(b) USNRC letter, D. G. Eisenhut to All Light Water Reactor Licensees dated February 23, 1980

Subject:

LWR Primary Coolant System Pressure Isolation Valves

Dear Sir:

We have reviewed the high pressure primary coolant piping systems at Vermont Yankee and conclude that an Event V valve configuration, as described in Reference (b), does not exist at our facility.

In addition, the concerns expressed in Reference (b) about possibl e mul tipl e check val ve failures causing a LOCA which bypasses the containment had already been specifically addressed by the NRC Inspection Team which visited the plant during Jul y 18-20,1979.

This team reviewed in detail the pl ant's val ve configurations and In-Service Inspection and Test Program and found them satisfactory.

The NRC Inspection Team indicated that only the Residual Heat Removal (RHR) and Core Spray System configurations were of concern due to the possibility of a LOCA which bypasses the containment.

In both of these systems there is one check valve inside the containment and two motor operated valves (MOV's) outside, one of which is normally open, in high pressure piping.

Surveillance testing, which will determine if the check val ve is stuck open, is performed on the MOV's.

This testing is now done monthly, but will be done quarterly when Technical Specifications implementing the ASME Section XI ISI/IST program for Vermont Yankee are approved by the NRC.

Prior to performing surveillance testing on these valves, plant procedures require that the adjacent valve be locally verified as being in the closed position.

Additionally, in the RHR system, a pressure gage is installed on a drain line located between the check valve and the first MOV in each injection line.

By procedure, these gages are checked by an operator once per shift to assure check valve integrity.

8003200 a

o Unitsd States Nuc1 car Rzgulatory Commission March _14, 1980 Office of Nuclear Reactor Regulation Page 2 4 In light of the above information, no plant modifications, changes to the current ISI/IST program, or changes to plant procedures are necessary to increase valve reliability. We believe that this letter fully responds to the intent of the concerns expressed in Reference (b). However, should you have any further questions, please contact us. Very truly yours. VERMONT YANKEE NUCLEAR POWER CORPORATION 's>tN' D. E. Vandenburgh Vice President RLS/ncj COMMONWEALTH OF MASSACHUSETTS) )ss COUNTY OF WORCESTER ) Then personally appeared before me, D. E. Vandenburgh, who, being duly sworn, did state that he is a Vice President of Vermont Yankee Nuclear Power Corporation, that he is duly authorized to execute and file the foregoing request in the name and on the behal f of Vermont Yankee Nuclear Power Corporation, and that the statements therein are true to the best of his knowledge and belief. Robert H. Groce Notary Public My Commission Expires September 14, 1984 c .+ .i- .;: ;Q, $ y, u ',* 1 '[' ,c ' O, s [

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