ML20045B541

Responds to NRC 930324 Request for Addl Info Re License Change Requests 199 & 66 to Licenses DPR-66 & NPF-73, Respectively,Changing TS Re Containment Airlock Door.Request Duplicates Requirements Contained in NUREG-1431

ML20045B541
Person / Time
Site:	Beaver Valley
Issue date:	06/10/1993
From:	Sieber J DUQUESNE LIGHT CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML20045B542	List: ML20045B541 ML20045B543
References
RTR-NUREG-1431 TAC-M84223, TAC-M84224, NUDOCS 9306180052
Download: ML20045B541 (5)

Text

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Shippingport, PA 15077-0004 JOHN D. SIEBER (412) 393-5255 Senior Vice Preseoent and June 10, 1993 rax (4 2) 843mo Chef Nuclear Officer Nuchar Power Division i

U.

S.

Nuclear Regulatory Commission Attn:

Document Control Desk Washington, DC 20555

Subject:

Beaver Valley Power Station, Unit No. 1 and No. 2 BV-1 Docket No. 50-334, License No. DPR-66 BV-2 Docket No. 50-412, License No. NPF-73 Response to RAI; License Change Requests 199/66 (TAC Nos. M84223/M84224)

This submittal is provided in response to your March 24, 1993, request for additional information (RAI) related to License Change Requests 199 and 66, concerning the Containment Air Lock Door-Technical Specification changes.

The specific questions are stated below followed by our response.

Certain aspects of the standard technical specifications'for Westinghouse designed reactors appear not.to be addressed in the September 16, 1992 proposal.

Please address the following:

1.

In LCOs 3.6.1.3.a.1 and 3.6.1.3.b, verification within 1 hour-that an operable door is closed.

Response

This concern is contained in NUREG-1431 as required Action A.1.

The Bases section of NUREG-1431 discusses this action requirement-by stating "With one air lock door in one or more containment air locks inoperable, the OPERABLE door must be verified closed (Required Action A.1) in each affected containment air lock.

This ensures that a leak tight containment barrier is' maintained.

by the use of an OPERABLE air lock door."

Since Beaver Valley operates with a sub-atmospheric-containment, we must always have at least one containment air lock door closed to maintain vacuum.

This is reflected in the existing LCO 3.6.1.3.a for each unit.

Additionally, existing Action a.1 and

b. require that we maintain an air lock door closed.

We conclude that the existing technical specification adequately.

addresses this concern.

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Response to RAI; License Change Requests 199/66 (TAC Nos. M84223/M84224)

Page 2 2.

In LOO 3.6.1.3.a.1, limitation of entry and exit to 7 days when both air locks are inoperable.

Response

This concern is contained in NUREG-1431 as a note associated with Condition A,

"One or more containment air locks with one containment air lock door inoperable."

The Bases section of NUREG-1431 discusses this note by indicating entry and exit is permissible under administrative controls.

It further states,

'This allowance is acceptable due to the low probability of an event that could pressurize the containment during the short time that the OPERABLE door is expected to be open."

This note, as presented in the Bases, does not appear to apply to containments of a sub-atmospheric design since a sub-atmospheric condition cannot be maintained with both doors open at the same time.

Beaver Valley has had situations occur where the inner air lock door is declared inoperable due to failure to meet the air lock door seal leakage surveillance requirements.

When these instances occur during power operation, entry and exit may be desirable in order to implement repairs.

This is the basis for the additic*. of the following note in our proposed license change request:

Note (1)

Entry and exit is permissible to perform repairs of the inner air lock door.

In

addition, the NUREG-1431 Bases indicate that 7

days are permitted to allow containment entry for performance of technical specification surveillances and required

actions, as well as other activities.

However, there is no further action required to be taken after 7

days and plant operation would continue indefinitely.

The need to conduct technical specification other required actions may easily extend beyond surveillances or 7

days.

On this basic, it is believed inappropriate to limit entry and exit to 7 days.

We conclude that the proposed change to the technical specifications adequately addresses this concern.

3.

In LCO 3.6.1.3.b, initiation of action to evaluate overall containment leakage per the appropriate LCC), and

Response

This concern is contained in NUREG-1431 as required Action C.1.

The Bases section of NUREG-1431 discusses this required action to

}

Response to RAI; License Change Requests 199/66 (TAC Nos. M84223/M84224)

Page 2 i

B Ouestion 3 Response (Continued) be necessary "With one or more air locks inoperable for reasons other than those described in Condition A or B,..."

(Condition A exists when a

single air lock door in one or all air locks is inoperable.

Condition B

exists when an air lock interlock i

mechanism is inoperable on one or all air locks.)

NUREG-1431 Action C.1 is intended to demonstrate that the containment remains operable in the event both doors in an air lock have failed a

seal test or overall air lock leakage is not within limits.

(It is possible that, even with both doors failing the seal

test, the overall containment leakage rate can still be within limits.)

Although existing LCO Action 3.6.1.3.b does not require initiation of an evaluation, we believe our current specification

[

is adequate and safe.

Surveillance Requirement 4.6.1.3.a requires a

door seal test be performed, or that the total air lock leakage be quantified to insure the air lock meets its LCO overall leakage requirements.

In the event we do not meet the total air lock leakage requirements, we would then declare the air lock inoperable and take the appropriate actions.

This is a more conservative position than that supported by~NUREG-1431.

It is very likely that with the Beaver Valley sub-atmospheric containment design, if the air lock leakage limits were exceeded, se would start approaching the operating limits associated with LCO 3.6.1.4 - Internal Pressure.

We conclude that the existing technical specification conservatively addresses this concern.

4.

In LCO 3.6.1.3.b, reference to inoperable interlock mechanism.

Response

This concern is contained in NUREG-1431 as Condition B, "One or more containment air locks with containment air lock interlock mechanism inoperable."

The proposed change request added an Action c. which duplicates the requirements contained in NUREG-1431 Condition B.

This action was added as a

result of our experiences involving interlock problems.

The additional action statement would permit extended plant operation and provide an approach to implement i

repairs under the strict control of a dedicated individual.

This proposed change was patterned after NUREG-1431, proof-and-review.

It was our choice to add it as LCO 3.6.1.3.c versus LCO 3.6.1.3.b.

LCO 3.6.1.3.b is intended to address j

situations not covered by LCO 3.6.1.3.a or LCO 3.6.1.3.c.

We conclude that the proposed change to the technical specifications adequately addresses this concern.

i T-

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a Response to RAI; License Change Requests 199/66 (TAC Nos. M84223/M84224)

Page 2 5.

Any change in Bases needed to be consistent with the changes proposed for Section 3/4.6.1.3.

Response

Attachment 1

contains a

revised Bases section which includes additional details supporting our proposed changes.

If you have any questions regarding this submittal, please contact Mr. Steve Sovick at (412) 393-5211.

Sincerely,

h \\

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D.

Sieber i

i Attachment cc: Mr.

L.

W.

Rossbach, Sr. Resident Inspector Mr.

T.

T.

Martin, NRC Region I Administrator Mr.

G.

E.

Edison, Project Manager Mr.

W.

P.

Dornsife, Director BRP/ DER Mr. R.

J. Barkanic. BPP/ DER Mr.

M.

L. Bowling (VEPCO) i f

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