ML19268C107

Forwards Request for Info Needed for Review of Util 781102 Response to Auxiliary Feedwater Sys Requirements.Answer Should Be Submitted by 791217

ML19268C107
Person / Time
Site:	North Anna
Issue date:	12/14/1979
From:	Schwencer A Office of Nuclear Reactor Regulation
To:	Proffitt W VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.)
References
NUDOCS 7912310159
Download: ML19268C107 (5)

Text

D_ i stri bution (NRCFDR Docket FiJe Local PDR ORB #1 Reading MCEER 14 E79 NRR Reading O. Eisenhut B. Grimes W. Gammill T, J. Carter W. Russell Docket No. 50-338 Attorney, OELD Ol&E,(3)

Mr. W. L. Proffitt A. Schwencer Senior Vice President - Power W. Ross Operations C. Parrish Virginia Electric and Power Company NSIC Post Office Box 26666 TERA Richmond, Virginia 23261 ACRS (16)

Subject:

Request for Information for North Anna Power Station, Unit No. 1 Auxiliary Feedwater System Our review of your November 2.1978 response to the NRC requirements for auxiliary feedwater systems dated September 28, 1979 requires additional information so that we can complete our review. Our request for information is provided in the enclosure to this letter.

On Occember 11,1979, we telecopied the attached request for information to your Mr. E. Grechek. The items in the enclosure are numbered to correspond with the recorcendation numbering of the NRC requirements for auxiliary feedwater systems at North Anna Unit No. 1.

We request that your response to the open itemc in the enclosure be provided to us by December 17, 1979, so that we can complete and issue our atxiliary feedwater system safety evaluation report for North Anna, Unit No. 1.

Sincerely, Original signed by A. Schwencer, Chief Operating Reactors Branch No.1 Division of Operating Reactors

Enclosure:

Request for Additional i

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ENCLCSURE A.

Ino Ter: T.ece-endations O

1.

Esce-s.dations G3 4 The licensee's response is acceptable, j

2.

Recor endation GS-6 The licensee's respoise is acceptable.

3.

Pecomrendation GS-7_

Based on our review of the North Anna 1 FSAR, we concur with the licensee's response that he has verified that the AN system auto-matic initiation signals and associated circuitry are safety grade.

B.

Additiorgi Short Tere Recor=endetions 1.

The licensae's response is partially acceptable but requires resolu-lion of the following open items :

a) The licensee stated there are two low level alarms associated with the ECST. However, the alarms are both generated by the same ;ransmitter. This does not meet our single failure criterion.

In order to use the AN pump suction pressure indicators as backuo to the ECST level indication and slarm, we require that you provide redundant low level alarms that will alert the operator at least 20 minutes before the ECST will empty assuming the largest AW pump is operating, b)

The procedure being modified to instruct operating personnel to monito-AN ou.p suction pressure and ECST level indicators snoule also ins *ruct the operators how to correlate pump suction pressu-e witn ECST level hen the ovmp(s) is operating.

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I 2

The licer.see's response indicated a p::e-ttsi ecnf'ict between our requirement for a 72-hour endurance tu: Or the turbine driven AFW pump and the 72-hour LCO in Technical be:ift:atien 3.7.1.2.

The provisions of the attached revised Ad: :f oral Short Term Recommenda-tion No. 2 should resolve this potential ccnflict. The licensee should commit to follow the provisions of the attached revised AN pump endurance test provisions and sub-i; t :e requested test infor-mation.

3.

The licer.see's response to this recotrandation was not complete.

however, based on information in the ti:rth Anna FSAP, and in his response dated November 26, 1979, to : e NT ~(t.enten) letter of 0:tober 30,1979, we consider that upo: accomplishing the committed power supply modification scheduled fo cocpletion before unit startup, the AFW flow indication systen vill neet safety grade require-ments.

4 The li:entee's response is acceptable.

C.

Lone Term Recommendation 1.

The licensee's response is acceptable '.see A.1 above).

D, Basis for AW System Flow Recuirements The licensee should provide a commitment :t e 3:r res::. ding to this infor-mation re:.;ested in Enclosure 2 of the NF" ' t::t-da:et September 25, 1979 9500D142

F.evision to F.e::- endation No. 2 of aAdditional Short Terr

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Fe:om endations* F.egarding Auxiliary Feedwater Fump Endurance Test The licensee should ;trform an endurance test on all AFW syste.m pumps. Tne test should continue for at least 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> after achieving the following test conditions:

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- pump / driver operating at rated speed and

- pump developing rated discharge pressure and flow or some higher pressure at a reduced flow but not exceeding the pump vendor. maximum percitted discharge pressure y,alue for a 48-hour test

~- For turbine drivers, steam temperature should be as close to normal operiting steam temperature as practicable but in no case should the temperature be less than 400*F.

Following the 48-hour pump run, the pumps should be :, hut down and allo'wed to cool down until pump temperatures reduce to within 7.0*F of their values at the start of the 45-hour test and at least 8 h urs have elapsed.

Following the cool down, the pumps should be started and run fo. one hour.

Test acceptance criteria should include de::enstratir,g that the pumps remain within design l'icits with respect to bearing / bearing oil tempera-tures and vibration anc that ambient pump room conditions (temperature, humidity) do net exceed environmental qualificati:n limits for safety-related e:;uipment ir the roem, n.e li:ensee should :rovide a su=ary of the conditions and results of the tas:.

Tne su wry sh: 1d include the fo11 ewing: 1) A trief descripti:n

f tne tes; method (in:le:ing flow s: hematic dia; ram) ar.d how the test 95000143

w2s instrumented (i.e., where and h w bearirg temperatures were measured).

2) A discussion of how the test conditions (; ump flew, head, speed and steam' temperature) compare to design operating conditions.

3) plots of bearing / bearing oil temperature vs. time for each bearing of each AFW pump / driver demonstrat'.

hat temperature design limits were not exceeded. 4) A plot of pump room ambient temperature and humidity vs.

tice demonstrating that the pump room ambier.t conditions do not exceed environmental qualification limits for safety-related equipment in the room. 5) A statement confirming that the pump vibration did not exceed allowable limits during tests.

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