ML20080U534

Advises That Util Will Continue to Operate Vent & Purge Valves for Inspecting Rcpb,In Response to NRC . Vent & Purge Valve Data Encl

ML20080U534
Person / Time
Site:	FitzPatrick
Issue date:	02/24/1984
From:	Bayne J POWER AUTHORITY OF THE STATE OF NEW YORK (NEW YORK
To:	Vassallo D Office of Nuclear Reactor Regulation
References
JPN-84-14, NUDOCS 8403020351
Download: ML20080U534 (4)

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February 24, 1984 JPN-84-14 Director of Nuclear Reactc. Regulation U. S. Nuclear Regulatory Commission Washington, D.C. 20555 Attention: Mr. Domenic B. Vassallo, Chief Operating Reactors Branch No. 2 Division of Licensing

Subject:

James A. FitzPatrick Nuclear Power Plant Docket No. 50-333 Containment Vent and Purge Valve Operability

References:

1. NRC letter, D. B. Vassallo to J. P. Bayne, dated January 13, 1984, " Containment Vent Valve Operability."

2. PASNY letter, J. P. Bayne to T. A. Ippolito

_(NRC), dated May 12, 1981 (JPN-81-34),

" Containment Purging and Venting During Normal Operation."

3. PASNY letter, J. P. Bayne to T. A. Ippolito (NRC), dated June 13, 1980 (JPN-80-29),

" Containment Vent and Purge System."

4. PASNY letter, P. J. Early to T. A. Ippolito (NRC), dated May 6, 1980 (JPN-80-26),

" Containment Purge and Vent System Isolation Valve Operability."

Dear Sir:

Reference 1 identified NRC concerns regarding the ability of containment vent and purge valves to_close under conditions of non-uniform flow. Tne NRC considers operability questionable if the valve is downstream of, and in close proximity to, a pipe fitting such as an elbow or tee. In response to these concerns, the Authority has performed a preliminary reassessment of the FitzPatrick plant vent and purge valves. This is in addition to previous operability reassessments whicn were performed by the Authority and described in References 2, 3 and 4.

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8403020351 840224 PDR ADOCK 05000333 P PDR 3

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'1' Pla'nt drawings show that valves 27-A0V-117-and 27-A0V-118 are

. located downstream of,the nearest pipe fitting by distances

-of 11'.5 and_13; pipe diameters respectively. These valves are locaced.in'a. region of fully ~ developed, uniform flow and meet

, . .the criteria of Reference 1 for operability. Therefore, the

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Authority will continue to use these valves in accordance 1with.our-normal operating procedures. Currently, these valves are.only opened to maintain the drywell to torus

differential pressure, as: required by the FitzPatrick

-Technical. Specifications, and to inert and deinert the containment.-

The; Authority could_not~ complete a comprehensive test program

- sto' reaffirm.the. operability of valves 27-A0V-lll through L27-AOV-116 prior;to responding to-Reference 1. However, a programfis currently being planned and-the results will be provided'to1the NRC:asEsoon as the program can be completed.

The Authority anticipates that' program development, valve

-testing and. data analysis will require several months to

' complete. Since-valves of.the type installed in the

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PitzPatrick-plant are madeito order, valves for testing are.

not available.from the' manufacturer, zIf' suitable valves

' : cannot te: located, _ several -additional months will be required

- -for~ valve fabrication.

In the interim,$the Ahthoritylconsiders' the.use of these

. valves, which.is strictly. limited, necessary to preserve the

, .abilityfto safely operate =the plant. Valves 27-AOV-111 through 27-AOV-116_are.normally closed in order-.to maintain containment in the inerted condition.- Valves must be opened

to _ perform the monthly _ surveillance test of J the drywell to torus vacuum breaker-valves which is required by the Technical' Specifications. However, as an interim measure,

containment-isolation will beLuaintained during this test by

other;non-safety related' valves which areilocated' downstream'.

I" These. valves must also be openedLin order to~ inert the containment following a TisualLinspectionLof the reactor

. coolant 7 system' pressure boundary, orfto deinert prior to such

.an1i nspection. This visual' inspection of the reactor coolant

system.is. conducted during startup and shutdown, while the yplant is hot. This inspection 1providas~~ additional assurance of reactor) coolant _ pressure boundary integrity,

which is'of

' prime importance.in' light'of intergranular. stress corrosion concerns.- If the vent.and purge valves cannot be opened unlesssthe: plant.is in~ cold shutdown,.then' containment must Lbe inerted~ prior t'o.heatup.(and cannot be deinerted before-cooldown) Land this' inspection cannot be' performed.

Although' testing' remains;to be completed,'the. Authority

.conaiders the probability.'of the failure of these valves to close to.be. extremely 10w for the following reasons. The

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m-valves.are_.only-openedffor short periods of time to allow for

.inerting'and~deinerting._ All of the valves'are blocked so that;they cannot'be opened more than-50 degrees, which is I V 5--" * - - .

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-little more than half way. As shown in Attachment 1, at least one valve in each line tends to close due to the is effects of flow. These valves close in'under 5 seconds, as required by Technical Specifications. Finally, the probability of an accident occurring while the valves are open is very low.

In summary, the Authority considers it beneficial to continue to_ operate the vent and purge valves for the purposes of inspecting the reactor coolant system pressure boundary.

Authority personnel are available to discuss our plans or the information we have submitted at any time. If you have any questions, please contact Mr. J. A. Gray, Jr. of my staff.

Very truly yours, bN . Ba ne

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Ex cu ive Vice President

) ~Nuc ar Generation-cc: Office of the Resident Inspector U. S. Nuclear Regulatory Commission P. O. Box 136 Lycoming, New York 130s3

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' llittle more than half way. As:shown in Attachment'1, at

"- .least-one: valve in each line tends to close due to the effects of flow. These valves close in under 5 seconds, as b-required by Technical Specifications. Finally, the probability of an accident occurring while the valves ars open "is very ' low. -

In sunmary,<-the Authority considers-it beneficial to continue to operate-.the. vent and purge valves for the purposes of inspecting the reactor . coolant system pressure boundary.

Authority personnel are available to discuss our plans or the information we have submitted at any time. If1you have any questions, please. contact Mr. J. A. Gray, Jr. of my staff.

O Very truly yours,

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Ob . Bayne .

Ex cu ive Vice President

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). Nuc ear Generction cc: Office of the Resident Inspector U.;S. Nuclear Regulatory-Commission-

-P.'O. Box 136 Lycoming, New York 13093 k

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Attachment 1 VENT AND PURGE VALVE DATA Orientation Flow Tends Valve No.- -Size Valve Location (in degrees) To 27-AOV-lll 24" Directly on 90 (See Note 3) outlet of elbow 27-AOV-112 24" Directly on branch 90 Close Valve cf reducing tee 27-AOV-113- 24" Directly on run 90 Close Valve of tee

.27-AOV-114 24" 2D from branen 0 (See Note 3) of tee 27-AOV-115 20" Approx. 2.5D 60 Close Valve from elbow 27-AOV-116 20" Approx. 1.5D 60 Open Valve from elbow 27-AOV-117 20" Approx. 11.5D N/A Valve is in a from elbow region of fully developed flow.

27-AOV-ll8' 20" Approx. 13D N/A Valve is in a from-elbow. region of fully developed flow.

Nctes:

' 1. "D" is defined as one pipe ~ diameter.

Distance from fitting is taken'from drawing.

2. The orientation is zero degrees when the valve shaft and pipe' fitting are in the. sane plane.

.3. .The tendency of the flow to either open or close the valve cannot'be determined without more detailed analysis.

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