ML20070V065

Forwards Relief Request CR-14 from Inservice Insp Program Re Performance of Leak Test Following Replacement of Three Electromagnetic Relief Valves & Pilot Valve Assembly on Fourth Valve During Forced Maint Outage

ML20070V065
Person / Time
Site:	Quad Cities
Issue date:	04/05/1991
From:	Richter M COMMONWEALTH EDISON CO.
To:	Murley T NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM), Office of Nuclear Reactor Regulation
References
NUDOCS 9104100259
Download: ML20070V065 (5)

Text

.,. - -.. -

- ~. - - - -. -

• ' * ~ " '

C:mm:n=ealth Ediscn 2

1400 Opus Place v

Downers Grove, Illinoin 00515 i

April 5, 1991 Dr. Thomas E. Murley, Director t

Office of Nuclear Reactor Regulation i

U.S, Nuclear Regulatory Commission Washington, D.C.

20555 l

Attn:

Document Control Desk

Subject:

Quad Citt'es Nuclear Power Station Units 1 snd 2 i

Submittal of Relief Request for Inservice Inspection Program RRC_DorlettloL_50-251And 50-265 i.

Reference:

R. Stols (CECO) letter to T. Murley (NRC),

dated January 21, 1991.

k Dr. Murley:

The referenced letter submitted a relief request to_-the Quad' Cities i

Station Inservice Inspection (ISI) Program which pertained:to the performance

~

j of the ASME Code (Section-XI). Class 1_ system leakage test following the_

replacement of three-(3) Electromatic Relief Valves (EMRV), and a.p1_ lot; valve assembly.on a fourth EMRV, during a forced maintenance outage.

The~ system-leakage test was required due to the disassembly and reassembly of. Class 1 mechanical connections, which'were not Isolable from.the reactor vessel', to support the. work on the EMRVs.

Based on the personnel exposure and critical 4

path outage impact for the performance of;the normal Class 1 system leakage =

test, Commonwealth Edison Company-(CECO) requested and received relief (on a "one-time" basis) from your staff to perform the leakage test:at 920 psig i

during the unit startup from the outage. During the discussions: with your staff for this. relief request, CECO indicated that rel_ief for these types of situations (disassembly / reassembly of unisolable, Class 1_ mechanical connections):would be pursued for the current ten-year interval of the Quad-Cities Station ISI Program. '.This letter presents that relief request, t

The attached relief request (CR-14) allows the Section XI Class 1 system leakage test for unisolable Class'1 mechanical connections (located in the drywell) to be performed at 920 psig during unit startup, when disassembly-

.and reassembly of these connections has occurred either: 1). subsequent to the-performance of the normal Class 1 system._ leakage test-(or. hydrostatic test) conducted near the end of each tefueling_ outage; or 2) during a forced maintenance outage in the course of-an operating cycle.

The relief request is for.the duration of the current ten-year-interval for the ISI Program,_which L

concludes on February 18, 1993 for Unit'I and March 10, 1993 for-Unit 2.

i y

9104100259 910405 F '

PDR ADOCK 05000254 U

i i

Q PDR j

I 1

Dr. T.E. Murley April 5, 1991 Please direct any questions or comments on this letter to this office.

Respectfully, W

6 e

M.H. Richter Nuclear Licensing Administrator

Attachment:

Relief Request Number CR-14 for Quad Cities Station cc:

A.D. Davis - Regional-Administrator, Regien III 1

L.N. Olshan - NRR Project Manager, Guad Cities T.E. Taylor - Senior Resident Inspector Quatl Cities R. A. Hermann - NRR Technical Staff MR:cag ZNLD861/6-7

4 ATTACHMENT RELIEF REQUEST NUMBER CR-14 FOR QUAD CITIES STATION 3HLD/861/6

r 4

RELIEF REOUISLHUMBER:

CR COME0EHLIDMEI.CAHON Code Class:

1

References:

Article IHA-5211(a)

.Atticle IHB-5221(a)

Examination Category:

B-P Item Number:

B15.50, B15.60, B15.70

==

Description:==

System leakage test pressure for the disassembly and reassembly of Class 1 mechanical connections, i

CQDLREQUIAEEE f

IHA-5211(a) requires a system leakage test to be conducted following the opening and reclosing of a component in the system after pressurization to nominal operating pressure.

IHB-5221(a) states that the system leakage test shall be conducted at a test pressure not less than the. nominal operating pressure associated with 100%

rated reactor power.

BAHS FOR RELIIE The nominal operating pressure associated with 100% rated-reactor power is 1,000 psig.

Near the end of each refueling outage, a system leak 4ge test.at 1,000 psig, or a hydrostatic _ test at 1,l_10-psig, of all Class:1 pressure retaining-components is conducted.

Subsequent to the system leakage test or the hydrostatic-test during a refueling outage, or during forced-maintenance outages which can occur' during an operating cycle, it may become necessary to: disassemble and reassemble.

Class 1 mechanical connections that are. located in the drywell and cannot be Isolated from the reactor vessel.

For these situations, the performance of a Class 1 system leakage test at 1,000 psig would have a significant impact on the unit's critical path outage time and personnel exposure.

The normal Class =1 system leakage: test, which'is performed-with the vessel flooded up, requires numerous equipment outages (e.g., in excess-of_300 valves-must be taken out-of-service, Main Steam safety valves must be: gagged).

Performance of the equipment' outages, coupled with the performance _of the system leakage test, takes approximately'S days (3 shifts per day) with a total personnel exposure of approximately 2.5 Man-Rem.

Performance of a system leakage test using reactor pressure-during unit startup.is possible,-however, the test can not-be performed at 1,000 psig.

During unit startup, the Electro-Hydraulic Control System-precludes a reactor pressure above 950 psig without significant-increases in' reactor power.

In order to achieve a pressure of 1,000 psig, the reactor v:Aild have to be at approximately-100% rated power.

The radiation levels in'the drywell at this-power level are prohibitive, and prevent drywell entry by plant personnel.

Page 1 of 2-1NLD/861/7

=.

A drywell entry to inspect _for' leakage can be performed at' 920-psig, which is associated with approximately 15% reactor power. ' Performance of the leakage test in this manner would have an-insignificant: impact on the ability to=

-detect leakage from a~ reassembled mechanical connection. -It would also significantly reduce the personnel exposure _and critical-path outageLtime required for the test.

ERQEOSI0lLTERNATE-EXAMINATIQN A system leakage test at 920 psig during unit startup.wlli be performed when an-unisolable-Class 1 mechanical: connection in_the drywell has-been-disassembled and reassembled _el_ther: _l)-subsequent to the performance of the normal Class-1 system leakage test _or hydro _ static test conducted near-the end-of each refueling outage; or 2)-during.a forced maintenance-outage in the-course of an operating cycle.

APPLICABLE TIME PERLQD Rellef is requested for the-current ten-year: Interval _of;the Inservice <

Inspection Program for Units 1 and 2-(which concludes::on February 18 1993 for

-Unit 1 and-March =10, 1993 for. Unit 2).

f s

1 p

l lr

.t

• ?

Page 2.of 2 2H!,D/ 861/1

..-....,~._.......,_.......-_.-,-...u.

-