ML18082A870

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Forward Auxiliary Sys Branch SER Input on Implementation of Recommendations for Auxiliary Feedwater Sys
ML18082A870
Person / Time
Site: 05000000, Salem
Issue date: 07/30/1980
From: Check P
Office of Nuclear Reactor Regulation
To: Novak T, Tedesco R
Office of Nuclear Reactor Regulation
Shared Package
ML093450149 List: ... further results
References
FOIA-80-515, FOIA-80-555 NUDOCS 8008130632
Download: ML18082A870 (19)
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~rtTR/\\L FILE SRR ASB READING PCheck JUL 3 0 1980 Docket ilos:

50-272/ 311 MEMORANDUM FOR:

Robert L.* ',Tedesco, Assistant Director for Licensing, DL Thomas M. Novak, Assistant Director for Operatjng Reactors7 DL FROM:.

Paul S. Check, Assistant Director,

for Plant Systems, DSI

SUBJECT:

SALEM NUCLEAR GENERATING STATION UNITS 1 & 2 - SAFETY EVALUATION REPORT - INPUT ON THE IMPLEMENTATION OF RECOMMENDATIONS FOR THE' AUXILIARY FEEDHATER SYSTEM Enclosure l provides the Auxiliary Systems Branch (ASB) Safety Evaluation Report (SER) input for the Salem Nuclear-Generating Station Auxiliary Feed-water System (Arns) reliability evaluation~ In a letter*dated September 21, 1979, the NRC forwarded to Pub 1 i c Service Electric and Gas Company cur requirements regarding the Salem Unit 1 Arns.

These requiresents are.

identified in NUREG-0611 11 Generic Evaluation of Feedwater Transients and Small Break Loss of Coolant Accidents in Westinghouse-Designed Operating Pl a11ts.

11 Public Service provided responses in 1 etters dated November 1,

1979, May 5, 1980, and June 11, 1980.

In a June 18, 1980 meeting with Public Service on Salem Unit 2, the licensee made commitments to document the similarity of the Aft.JS design for Units l

~nd 2, including the related <<!nstrumentati(:m and controls (I&C) systems~ as well as that of pertinent technical specific~tdlons~ and to provide responses on all outstanding issues.

The licensee documented the requested information in its letters of June 27, 1980, and July l, 1980.

In the June 27, 1980 letter it was stated that the AFWS design, including equipment and automatic initiation logic, is identical for both units.

There are, however, some differences in the technical speci fi ca ti ans.

The LPM for* Sal em Unit l is requested to have the Salem 1 technical specifications made identical to those for Salem Unit 2.

In the *July 1, 1980 letter, ddditional information was provided on outstanding i*ssues, including an analysis on the effect of using the saline service water system as backup to the normal auxiliary feed-V'mter supply, and other-outstanding system reliability issues.

. The SER contains three items for which our review is not complete:

l. Additional Recommendation 3 - }:he §afety grade design (long term require-ment) for auxiliary feedwater flow indication is still under staff review.

Our evaluation wi'll be presented in a supplement to this SER.

This is a

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R. Tedesco & *JUL 3 0 1980 2..

Long Term Recommendatton GL-g - The 1 i censee' s analysis on the effects of l!tilizing the saline service ~wter system as an assured backup* ~o the normal auxiliary feedwater supply is still under staff review. *our evaluation will *be pre.sented in a supplement to this SER.

3.

Long Term Recommendation GL The safety *grade design for auxiliary feedwater automatic initiation signals and circuits is still under staff

. review *. Our evaluation will be presented i'n a supplement to this SER.

This is a dated requirement.

  • Original Signed bJ;

.*ij-a~l S, Checli:i Paul S. Check, Assistant Director for Pl ant Sys terns Dtvi sion of Systems Integration

Enclosure:

A'S stated cc:

0. Parr OF'P'ICll:.
  • URNAllK.

DATii:.

R. Satterfield

. T. Speis

~'1. Butler S. Varga A. Schwencer vi. Ross 1J. Kerri g'an B. Mann

-Jr u.c. GDVl!RNMENT P'RINTING Ol"ll"ICEn tl71. aeo.. 789

SAFETY EVALUATION REPORT SALEM NUCLEAR GENERATING STATION, UNITS 1 & 2 IMPLEMENTATIONS OE' RECOMMENDATIONS FOR AUXILIARY FEEDWATER SYSTEMS I.

Introduction and Background The Three Mile.Island Unit 2 (TMI-2} accident and subsequent investigations and studies highlighted the importanc~ of the Auxiliary Feedwater System (AFl:JS) in the mitigation of transients and accidents.

As part of our assessment of the TMI-2 accident and r~lated implications for operating plants, we evaluated the AFW systems for all operating and near-term operating license plants having nuclear steam supply systems (NSSS) designed by Westinghouse (NUREG-0611) or Combustion Engineering (NUREG-0635).

Our evaluations of these system designs are contained in the NUREGs along with our recommendations for each plant and the concerns which 1 ed to each recommendation.

The objectives of the eva 1 ua-ti on were to:

(1) identify necessary changes in Aflol system design or related procedures in order to assure the safe operation of these ~lants, and (2) to identify other system characteristics of the APd systems which, on a long term basis, may require system modifications.

To accomplish these objectives, we:

(l}

Reviewed plant specific AFW system designs in light of current regulatory requirements (SRP) and, (2) Assessed the relative reliability of the various.AFW systems under various loss of feedwater transients (one of which was the initiating event of TMI-2) and other postulated failure conditions by determining the po ten ti al for AFW system failure due to corrnnon causes, single point vulnerabilities, and human error.

  • . *we concluded that the.implemen'tation of° the recommendations identified during this review. will considerably improve the rellability of the AFW systems for each operating plant.

- The following plant specific recommendations did not apply to this plant:

GS"." l, GS-5, GS-8,. G~-1 and GL-3.

The basis for these recommerrdations can be,.

_fo*und in Appendix III of:NUREG-0611, and the system descrfptiori-which determined the basis for not applying* these recommendations can be found in Appendix x of ~juREG-0611.

II.

Iinp1ementation of Our Recommendations A.

Short Tenn Reco111T1endations 1.. Recommendation GS 11The licensee should lock open single valves or - _

multiple valves in series in the AFW system pump suction piping and *

.lock -0pert other singl~ valve~ or mul~iple valves in seriei that ~ould interrupt all AFW flow.

Monthly inspections should be :performed to*

verify that these valves are locked and in.the open position. These

.. inspections _should be proposed for incorporation into th'e surveillance requirements of the plant Technical Specifications.

See Reconmendation.

GL-2 for the longer-term resol_ution of this concern.

11

  • .The,licensee,.in its letter of November 1, 1979, listed *the'manual

-.. v~1.ves in'thiscategory, and stated that SurveiHance Procedure SP(O}

  • 4.7. l.2(a) is being revi_sed to denote that these valves will be locked.*

ooen.

Th i's procedure will be perfonned once a month.. Techni ca 1

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2. Specification Surveillance Requirement 4.7.1.2 requi:res clarification to assure that lo.eked vaives are checked monthly.for proper position.

We have.reviewed the licensee's response andconclude that recommendation GS-2 is adequately m.et, and, therefore, acceptable, pending verifica:-

. tion of these surveil 1 ance. procedures by the Office of Inspection and Enforcement.

Recommendation GS-3 ~

1'l"he 1 i censee has stated that ft throttles.AR.f

. *system flow to avoid water hammer.

The licensee should reexamine the practice of throttling AFW system flow to avoid water.haminer.

The licensee should verify that* the AFW system will supply on demand

. suffi.cient ini tia 1 fl ow to the necessary steam generators to. assure adequate decay heat removal following loss of main feedwater flow and

In cases where this reevaiuation results*

ih an increase in initial J\\FW system flow, :the licensee should provide sufficient information to demonstrate that the requfred initial AFW

  • system flow will not result in plant damage due to water hammer.

11

. Subsequent to the transmi tta 1 of this recommendation, NRC, by 1 etter of November, 20, 1979, issued A~endment No. 22 to Facility Operating License No_. DPR-70 for Salem Unit 1. This amendment lifted a previous

, restrietion. of L~ 'fn./!T1inuteon secondar~~ water lev~l rise in the event

. of lo'.# steam gener~tor l~vel but set forth criteria. for operating. oroce-.

dures which include a limitation of.. auxiliary feedwater flow of 200 gallons

  • per minute per steam**gener.ator when coincidentally:ai_l water flow to the feedri'ng ha*s been irit_errupted for m~re than fiv~ 'minutes and the ~1ater *
  • 1 evel in the steam genera for ; s be 1 ow the to11 of the feedri ng...

-4~

The 1 icensee, in its letter of October 30, l979~ on the subject of feedwater hammer, committed to perform a test on Saiem U~it 2 to demon-*

st rate tha.t unacceptab 1 e feedwater hammer wi 11 not result from anti ci :-

pated* feedwater.transients* to the steam generator.

Assuming satis-factory test !lerfonnaricP.~. tlie 1 icen~ee cnult1 increas~r the max.imum.

  • allowed feedwater flow rate to a steam generator with an uncovered feedring to the maximum flow rate obtained in the test without experiencing water ha111111er~*

Our review of the.licensee's submittal of June 11~ 1980, providing the basis for AFWS flow requirements (see item D of this report) indi-

. cates.that the minimum AFW flow requirement (440 gpm) is compatible. *

.wi'th the existing flow limitation.

We conclude that recommendation*

GS~3.is adequately met, and therefore, acceptable~ providing.*the llcensee successfully perfonns the proposed water hammer test, based on an NRC approved procedure.

If. the. test is unsuccessful, we will require modifications and will provide a safety evaluation regarding the tests and modlficatiOns..

3**.

Recommendation GS-4_*- "Emergency° procedures for transferring _to alter:-

nate sources of AFW supply should be a:vailable to the plant operators.

  • .These* procedures should include criteria.to inf6rm the operator when, and in what. order~ ttie transfer to alternate 1/iate.r sources should take*

place.

The following cases should be.covered*bythe procedures:

-The case in wh1ch ~he.primary water supply is not initially*

available.

Th~-procedures for this case*-~hould include any

  • , operator.actions 'required to. protect the AFW.system pumps.*

'.. against sel f*damag~.before ~at~r flqw is* initiated; and.~

~

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'9 - The case in* which the primary water supply is being depleted~

The procedure for this case should p;ovide for transfer. to the alternate 'water s*ources prior to draining of' the primary_

It

. water supply..

  • The licensee, in its letter of N_ovember, 1,. 1979,' stated that its operating procedures* provide deta.iled steps to transfer. the auxiliary feedwater pump suction to an alternate source.

In 'our letter of April 4, 1980, we requested, that the n'ecessa:r.v procedures be pro-vided to.use all alternate water sources, e."g. Demineralized Water Storage Tank, Fire Water Storage Tank-~*Service Water System, in a

  • preferred sequence.
  • The licensee agreed to meet this, request* in its letter of May 5~ i980. *In this letter it was also:noted that one

_* -alternate _flow path,from the* Demineralized)later Storage Tank incl.udes a seismic category-I, normally dry pipe routed through the.vital switchgear room.

In its letter of July 1, 1980, the licensee stated_

that 11modifications wi 11 be made to *the normal ly-operi drain,valve on*

this isolated section of pipe such that it w'fll be piped directly to a floor drain to preclude any potential for flooding the switchgear room.

We conclude that this modification is acceptable but require that the licensee should also -initiate a surveillance procedure to:

further preclude: any potential for flooding.t.he switchgear.room when this pipe is filled. \\ie conclude that recommendati'on GS-5 is ade~ *

  • cruately met," and*~ therefore, a~ceptable pe~ding verificat1on of the surveillance procedu'res by the dffi ce of Inspectio'n *and Enforcement.

. i*

      • .**I"

,*_** 4.

Recommendation GS-6 -"The licensee should confirm.flow path avail-ability of. an AFW system flow train that has been out of service -to perform periodic testing or maintenan.ce as follows:

- Procedures _should be implemented to require an operator to'

  • determine that the APN system va~ves are properly_ aligned.
  • and a :second operafor to inqepehdently verify that the valves.

are *properly aligned~*

~The licensee should propose Technical Specifications to assure that prior to plant startup followin*g ~n extended cold *shutdown, a flow test would be performed to v~rify the normal flow path from the primary AFW system water source.to :th~ steam generators.*

The flow-test should be conducted with AFW system valves. iri their.

normal alignment.

11 In our position letter of April 4, 1980, we modified our requirements to the licensee as follows:

  • 111) revise station operating procedures to
  • require a. second operator to independently verify that the AFWS val.ves.

_are properly aligned after:the plant operator. performed his original AFWS fl ow pa th veri fi cations. per p 1 ant survei 11 ance procedures required after* the system has b~en_ out of. the _servi*ce, and* 2). verify ttiat: the Salem Station will use the AFWS for plant startup with all AFWS valves

. in their nonnal* alignment and' supplying water. from the primab water

  • sourc_e (the-Auxiliary _Feed*Storage.Tank)to the steam.gene.rators.

11

  • . The lice~see~ in its ietter of May 5, 1980~ agreed. to meet our require-*

ments ;* ; We conclude that recormiendation GS.::6 is adequately met, and'.

i

. ~1-the~fore, acceptable, pending v_~rification of operating and sur-veill.ance procedures by the Office of Inspection and Enfo_r2ement.

5.

Recommendation GS "The licensee should verify that the automatic start AFVJ system signals and associated circuitry are safety-grade.

If this cannot be. v~rified, the AFW system automatic. initiation system should be* mo.dified in the sh.ort:.term to meet the functi.onal*require-ments listed below..

For the longer term, the automatic initiation.

signals and circuits should be upgraded to meet safety-grade require-ments as* indicated in Reconmendation GL-5.

The design should provide for the automatic initiation of the auxi 1 i ary feedwater system fl ow~..

The automatic initi~tion signals and circuits should be designed so that a sirigle failure w~ll not result in the loss of auxiliary feedwater system func:tion.

  • Testability.of the*initiation signals and circuits shall be be a feature of the design~

The initi~tion signalS and circuits should be powered from the.emergency buses.*

Manual capability. to initiate. t.he auxiliary.feedwater system from the control room should be retained and should be implemented*so that a* single failure in the.manual circuits wi11 not result in.the. loss of system function,:

.. i The alternating current motor-driven pumps and valves.in the auxiliary feedwater system should be included in the automatic actuation (simultaneous and/or sequential) of the loads to the emergency buses.

The automatic initiation signals and circuits shall be designed so that their failure will not result in the loss of manual capability to-initiate the AFW system from the contra 1 room. 11 The licensee in its response of November 1, 1979, stated that the Salem Unit #1 AFWS has been designed to include the following:

l.

11A.utomatic initiation by the following detection signals will start the motor driven pumps~ loss of offsite power, loss of ~ain feedwater, lo~-low level in one steain generator and* '::a£2gu.arcs sequence signal.

Auto~atic start for the turbine driven pump is from loss of offsite power, low-low level in two steam generators and a 4 KV bus under voltage protection system signal.

2.

The automatic initiation signals and*

circuits are designed to prevent system malfunction for a signal failurer

3.

The system initiation signals and circuits are designed for complete testing.

4.

Power supply for the system circuits and initiation signals are from the unit vital buses.

5.

Manual initiation of the system may be accomplished from either the Control 2oom or locally at the pu.~ps.

The circuits for ~anual initiation are designed for single failure.

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6.

The motor.driven auxiliary feed~ater pumps are included a.s a part of the sequential loading for the emergency diesel generators.

7.

The failure of the automatic initiation signals and circuits will not effect the capability for *manual initiation of the system.

11 In Supolement #4, Part fI, to tne Salem SER (NUREG-0517), it was con-cluded that_ the Salem Unit 2 AFW ini.tiation ci_rcultry design meets NUREG-0578 shart-tenn (cnntrol 9rade) re<'_ufrer.ients*.

(See r,L-5 for long term implementation.} Since the design of the two units is identical, we conclude that recommendation GS-7 is adequately met, and therefore, acceptable for both Salem 1 and 2.

B.

Additional Short Term Recommendations

1.

Recommendation -'rhe licensee should provide redundant.level indica- *

. tions and low level alarms in the control room for the AFW system primary water supply to al low the operator to anticipate the need to make up water or transfer to an alternate water supply and prevent a low pump suction pressure condi.tion from occurring.

The low level alarm setpoint should allow at least 20 minutes for operator action, assuming that the largest capacity AR./ pump is ooerating.

11 In response to this recommendation, the licensee stated that the existing Auxi 1 i ary Feedwater Storage Tank includes both a low and a low-low level alann for Control Room annunciation and indication.

The low level alarm allows approximately 30 minutes for operator action and the low-low level 10 minute~.

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._.e*

-10"." -

In our pas i tion 1 etter. of Apri 1 4, 1980, to: the _licensee* we. stated 'that this design was acceptable for the short term.

For the l_ong term; we -

require the licensee to provide the follo11-1ing: _ 1) demonstrate redun-dant auxiliary _feedwater storage tank level indications and redundant -

level alarms ins.ide the control roorrr.;. 2)

The above* level.indications and alarms should be redundant all the way from the detectors at*the auxiiiaryfeedwaters:toragetank to the readouts and alarms inside the

.. control room.

Power supplies for.the 'level: indication arid alarms shduld also be redundant. Since *the auxiliary feedwater sto_rage tank is a seismic Category I water s'our:-ce, the entire water level indication *and alarm-system should in the long term be'designed to safety grade require"."

ments including _the use of Class lE circuitry and* power supplies, and

  • 3} reset the low-low level alarm to allow at least 20 minutes *for operator action~-- assuming that the largest capacity A-FW pump is operating.

The licensee in its _letter of May 5, 1980, agreed* to meet _these require-ments-.

We conclude that this recommendation is adeq*uately met, and, therefore, acceptable.

2.

Recommendation (This recommendation has** been revised from the origi.nal

11The li_censee should perform a 48_-hour endurance test on all Ai=W*systein pumps, if such a test or continuous

-. perio.d of oper:ation has.not been accomp_lished to date; Followiri~.the_*

48-hour pump run, the pumps shouldbe'shut down and cooled down arid.

then restarted and run for one hour. Test acceptance criteria should include demonstrating that the pumps remain within.design li'mits with respect_ to bearing/bearing_ oil temperat~res and vibration and that pun:ip

_room ambient conditions Ct~~perature, humidity) do not exceed environ:-.

. mental q_uai i fi.cation limits <for sa fet.Y:-rel ated-equipment _in the room.

~ll-The 1 icensee should provide a sulnmary of. th"e condition.s and results of.

the tests.

The surrmary should include.the following:* 1) A *brief de,scription of the test method (including flow* schematic diagram) and how the test was.instrumented (i.e., where and how bearing temperatures were measured).. -2) A disc~ssion of how the test conditions (pump flow;

  • head, speed and.steam temperature)-compare*to-design.operating con.di~

tians.

3) Plots:. of b_earing/bearing oil tempe-rature *vs. time for each -
  • bearing of each AFW pump/driver demonstrating that temperature design limits were not _exceeded.

4} A plot of pump rooni ambient temperature -

and ilumidi t.Y vs. time demonstrating that the-pump. room ambient con-di- --

tions do not exceed environmental q~al ification 1 imi ts for safety-related*

equipment in the room.

5) A _statement confirming that -the pump vibra-
  • ti on. did not exceed a 11 owabl e limits during tests.

The licensee in its l-etter of May 5, 1980, stated 'that the.tests have beeri completed on the Salem Unit 1 AFW pumps and that a report wi11 be ; ssued. In our meeting With the 1 i censee:_ on May 18; 1980, it was agreed that this report will be reviewed by Off'fce of Inspectibn and Enforcement. personnel.

For Salem Unit -2, a similar test will be

- performed prfor to reaching full power.

Based *on -these co!'l!"li i:Ments 7 we conclude that this recommendation is adequatelyniet, and, therefore, acceptable.

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I.

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- 3. _Recommendation -

1'fhe 1_icensee shouldimplement-the following requi.re-ments as specified by Item 2.1. 7.b on page A-32 of NUREG-0578:

11Safety-grade indication of auxiliary feedwater flow to each steam generator shal 1 -b*e provided in the. control room.

The auxi1 iary feedwater flow-instrument channels shal 1 be-powered from the emergency b'uses cons1stent with satisfying the em~rgency

  • power diversity requirements for the auxiliary.- feedwater sys.tern -

_set forth -in Auxiliary Systems.Branch Technical Position 10-1 of:

the Standard Review Plan, Se:tion 10;4.9~

11 In supplement #4 to. the Salem.Unit 2 SER (NUREG-0517) it is concluded that 11 the direct AR~ flow indication-arrangements pr6vided for*Salem Unit 2 satisfy' the ncontrol grade 11 requirements specified in the NUREG~

l 1 0578.position and-clarifications, and, therefore, are acceptable~

- Since the design of the two units is -identical-, this conclusion also --

a~~li:es ta* Salem Unlt l.

The 11safety-grade 11 requirements for this recommendation are still

- under review. *our evaluation of this matter-will be contained i_n a supplement to this_ SER

4.

Recommendation -'licensees with plants which requi_re local manual realignment of valves. to conduct periodic tests on one AFW system train a:nd which have only one remaining AFW train *available for operation, should propose Technical Specifications to provide that a dedicated 'individual 1'/ho is in co11111unication with the control room be stationed at the manual valves.

Upon instruction from the control room, this operator would re-align the valves in the AFW system train from the te:st mode to its operational alignment.

11 The licensee, in its letter of November 1, 1979, stated that, since there are three AFW pumps per unit, and the survei11ance procedures only allow testing of one pump at a time, the capability to deliver at least 100~~ of the required AFW flciw is maiiitained.

Two trains would still be. ava'fl able..

Ke. conclude that this re.commendation does not apply to Salem.

C.

Long Term Recommendations

1.

Recorrmendation GL 11Licensees*with plants in which all (primary and alternate) water supplies to the AFW systems pass through valves in a single flow path should install redundant parallel flow paths (piping and valves).

Licensees wi.th plants in which the primary AFW syst~m water supply passes through valves 1n a single flm'I path, but the alternate AFW

~,*-

I I

I I

I I

system water supp.lies connecf to the AFW system pump suction.piping downstream of *the above valve(s).* should' install redundant valves

  • parallel to the above valve(s} *or provide:automatic opening of the valve(s} from the alternate water supply upon low pump suction pres-sure.

The licensee should propose Technical Specifications to incorporate appropriate periodic inspections to verify the valve positiOAs.

The licensee, fn its 1 etter of Ju 1~, 1, 1980, agreed to remve the internals-of manual valve lAFl, located in: the common suction line to the three AFW pumps.

This is the only valve located in the common suction line> Removal of the valve internals precludes blockage of suction flow ta all three pumps by a single active failure or O!Jerator error.

We conclude that. recommendation GL-2 is adeq'uately* met~. and therefore, acceptable.

2.

Recommendation GL "Licensees having plants with unprotected normal

  • AFW system water supplies should evaluate the design of their AP.*/ sys-
  • terns to determine' if automatic protection: of the pumps is necessary fo'llowing a seismic event or a tornado.

The time available before pump damage_, the alarms and indications available to the control room

" operator, and' the ti'me necessary for assessing th~ problem and -takin*J I

action should be c~nsidered iri det~rmiriing whether operate~ action

.. can be relied on to prevent pump damage.

Consideration should be given to provicting pump protection by means such as automatic switch-over of th~ pump suctions. to the alternate safety-grade source: of

'*.. water, automatic pump trips on low suction pressure*, or upgrading the normal source-of water to meet seismic Category.I and tornado protec-.

  • tion requirements."

(Note:

this recommen(fation was *riot included in our September 21, _1979: requirements letter.)~_

The primary water supply for the AFWS. is maintained in the 220,000...

  • .. g~11on auxiliary feedwater storage tank {AFWST).* The water inventory is sufficient for about 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> -Of decay heat remova.l.

The. AFWST is*

seismic Category I but not tor:nado missile resistant.. Alternative water supply sources include the demineralized water storage tanks, and the fire protection and domestic water storage tanks, none of which are safety grade.

In the event tlie 'AF.WST is incapacitated by.a tornado missile strike, the seismic category I and tornado missile resistant service water sYstem can be 1 i ned up to supply auxi 1 i ary feedwater

  • by installation of a spool *piece.

In NUREG-0517,. Salem Unit 2 SER~ Supplement #4, it was concluded that.

a reasonable time estimate from the loss of the _AFWST. to completion*

of the spool piece connection is 53 minutes.. This time interval is acceptable based on a*n estimate of 70.minutes without cooling before

  • the.core begiris:to be.uncovered. It is contluded "that the appii-cants have the capability of. li_ning up the.service w'ater*system to the auxiliary feedwater pumps i'n a time interval :which assures that: the:

_core is adequately coolediri the eyent.. of loss* of an.normal water backup system."

Sfoce the units are identical, this* conclusion_

shouid apply to Salem Unit 1 also.

  • Subsequent*to publication of this supplement, two additional concerns were identified in this area.

The first concerns the possible hann-fuleffects of utilizing.the service water, which has a salt concen-tration* approximately half that of seawater. Since,. subsequent to a postulated i~ci dent; "the AFWS would have to be utilized for decay heat

be lined up, there.is some concern that sufficient salt.aould solidify to decrease steam generator heat transfer to unacceptable levels and also cause flow blockage. Another concern.is the possibility of unacceptable corrosion during this time.peridd. *The licensee has sub-mitted *aniianalysis on this subject iri its July 1, 1980 letter. This analysis is still. under-review..

The second concern involves installation of the spool piece during or right after. a tornado, when many acti.ons might have *to be taken at the.same time.. At the June 18 meeting on Salem Unit 2,.the licen-

  • see made a. commitment to modify plant procedures to. require spooi piece installation fo tne event of a* tornado warning.

We, ther~fore, consider thatthe licensee has adequately met this concern.

. Jhe licensee, in its June 27 letter, stated that the Salem. Unit* 2 Technical Specification~ contain annual. s.urvei1lance requirements to verify. that the service :water spool* piece is o.nsite.. W~ will require *

  • that the*Salem*Unit l Technical Specifications GOntain the same.

. requirements.

  • Our evaluation of this recommendation will be contained in a supple-ment to this SER.
3.

Recommendation GL 11The licensee should upgrade the AFW system auto-matic initiation signals and circuits to meet safety-grade require-men ts:

11 This. recommendation is still under review.

Our evaluation will be contained in a supplement to this SER.

0. Basis. for Auxiliary Feedwater System Flow Reauirements - We have reviewed the licensee's response on this subject and find it acceptable.
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