ML19347F944

Forwards Task Action Plan for Unresolved Safety Issue A-43. Reg Guides 1.79 & 1.82 Address ECCS Pump Performance & Sump Design Aspects.Sections of SRP NUREG-75/087 Address Adequate Pump NPSH

ML19347F944
Person / Time
Issue date:	05/13/1981
From:	Serkiz A Office of Nuclear Reactor Regulation
To:	Armstrong M STAFCO, INC.
References
RTR-NUREG-75-087, RTR-NUREG-75-87, RTR-REGGD-01.079, RTR-REGGD-01.082, RTR-REGGD-1.079, RTR-REGGD-1.082 NUDOCS 8105260668
Download: ML19347F944 (15)

Text

-

s a

'u

~

W 1.

(

NIM Gs\\

Qv Q 4 h

May 13, 1981 gy %

/

S

= fr 12 F

r a f.

.m

~

i r_

Mary Amstrong

[.c l

Stafco, Inc.

4 f

1819 H Street, N.W.

%,gs#

Room 230 l

l Washington, D. C.

20006

Subject:

Trans.nittal of TAP A-43, Centainment Emergency Sump Performance

Dear Ms. Amstrong:

Per our discussion of May 12, 1981, enclosed is a copy of the Task Action Plan (TAP) for the Unresolved Safety Issue (USI) A-43. This plan will provide you with an overview of our plans to resolve this particular USI. Regulatory Guides 1.79 and 1.82 currently address ECCS oump cerfomance and sume desian asoects. Various sections of NRC's Standard Review Plan (NUREG-75/087) also address related matters, such as adequate pump NPSH.

As I told you, we are in the midst o" activities related to resolving USI A-43.

I would recomend you call me back again relative to current status sometime in December 1981. Also, as technical reports relative to sump perfomance are developed, they will be filed in the NRC's Public Document Room (FDR). I would, therefore, suggest you check the POR files periodically.

l Sincerely, k

A. W. Serkiz, Task Manager Generic Issues Branch Division of Safety Technology

Enclosure:

TAP A-43 l

DIS BUTION l

l ERA NRC PDR A. Serkiz K. Kniel P. Norian A-43 File GIB Reading 8105260 i

Q.)

024591

((F c" cry DST:GIB Dfjp

' DST:c,IB g,'

l sen)[AWSerkiz:.,jb PEh r,i N

, kKniel.. f i

neffjfg1 n5//.7../01

~

em) 08i/f..)../a1 l

ac reau re oc m.aev cao OFFICIAL RECORD COPY

-" S* "+c - 3" + -

-.,* *s c,'\\

(mlTED0TbTEs o

[ '

.f' {

NUCLE AR REGULATORY COT.1".11SSIOt.'

wasmucioN o c.703n 3.gs, lg Gw. : ?

o,

\\,,, [.' '

May.13, 1981 Mary Annstrong Stafco, Inc.

1819 H Street, N.W.

Room 230 Washington, D. C.

20006

Subject:

Transmittal of TAP A-43, Containment Emergency Sump Performance

Dear Ms. Armstrong:

Per our discussion of May 12, 1981, enclosed is a copy of the Task Action Plan (TAP) for the Unresolved Safety Issue (USI) A-43.

This plan will provide you with an overview of our plans to resolve this particular USI.

Regulatory Guides 1.79 and 1.82 currently address ECCS pump performance and sumo design aspects. Various sections of NRC's Standard Review Plan (NUREG-75/087) also address related matters, such as adequate pump NPSH.

As I told you, we are in the midst of activities related to resolving USI A-43.

I would recommend you call me back again relative to current status sometime in December 1981. Also, as technical reports relative to sump performance are developed, they will be filed in the NRC's Public Document Room (PDR).

I would, therefore, suggest you check the PDR files periodically.

Sincerely, A. W. Serkiz, Task Manager Generic Issues Branch Division of Safety Technology l

Enclosure:

TAP A-43 l

s e,-

-~w

.---wy w--

e a, _ - _ -, - -,,

,,,,,m

,y

Task A-43 CONTAINMENT EMERGENCY' SUMP PERFORMANCE Lead NRC Organization:

Division of Reactor Safety Research (RES)

Implementation of Results:

Division of Licensing (NRR)

~

Lead Supervisor:

L.H. Sullivan, Acting Assistant Director for Water Reactor Safety Research NRR Cognizant Supervisor:

Karl Kniel, Chief, Generic Issues Branch, DST Task Manager:

A.W. Serkiz, Separate Effects Research Branch NRR Lead Reviewer F. Orr, RSB/DSI Applicability:

PWRs and BWRs Projected Cn pletion Date:

September 1983 e+

W e

a b

b b

k

9

s c

1 DESCRIPTICN OF PROBLEM in a PWR, water discharging During the initial Following a Ipss-of-coolant accident (LOCA)s on the containment fl 1

ling systems (ECCS) and containment When a low level is from the break collect.

portion of the LOCA, emergency core c,oospray syst large tank.

This ncy coolant sumps).Thus, the reached in the tank, the ECCS and C from the containment floor (containment emergelink for the safet irculation mode.

latter (or long-term) phase is called the reci ate reactor decay h containment and sumps become a key flowprovid control of containment conditions. containment and sump to the The importance of the flow link formed by t ecirculation has be h

Core Cooling operation of the safety systems during reRegulatory Guide 1.82, tional Testing of Emergency and Containment Spray Systems" provides s for some time.

Reactors" describes a pre-section of Regulatory Guide 1.79, "Preopera dequate NPSH for recirculation Core Cooling Systems for Pressurized Wateroper pumps and vortex control.

identified a number of degrade safety system (s) operation Plant reviews and centainment sump tests have i

A deficiency in NPSH causes pump cavitat on possible flow conditions which could instabilities, pump vibration and possible during the recirculation mode.

which in turn, can produce flowExcessive air entrainment due to Experience with the has revealed a number of deficien ffects.

hydraulic design (s) can produce similar e equipment failure.

formed according to the application of these Regulatory GuidesIt is now reco ld not consider several parameters i

provisions of Regulatory Guide 1.79 wouSafety is assu This has resulted i r to operation. utilities and rereview by -

critical to sump performance.

that successful tests are conducted pr oin the need in part, on an assump-the NRC staff.

d The provisions of Regulatory Guide 1.82 are base,

50% of the sump screen area.

a preoperational testquanti tative tion that debris will block not less than This 50% blockage value is currently imposed asThe a i

assessment of the potential for blockagef a large pipe break.

requirement.

which might be generated as a result o d to the sump can alter the f zump f

Debris blown off duri,ng a LOCA and transporteBlockage of the d air and increase pressure i

sump characteristics.

screens and trash racks can create condit ons Excest*ve blockage of trash racks or scre A vortex can simultaneously deliver entraine Flow from vrains or pipe breaks near the su losses *.to the pump inlet.

formation.

result in pump cavitation.can cause flow patterns conducive 5

1 i 4

d PWRs licensed prior to 1974 were not evaluated relative to the re: ire..c.L set forth in Regulatory Guices 3.82 anc 1.79; those plants were evaluated on a plant spectfic bases.

Regulatory Guide 1.79 requires pre-startup tests to verify vortex control and acceptable pressure drops across screening and suction lines and valves.

Regulatory ?uide 1.82 provides criteria for the design of reactor building sumps.

Boiling water reactors also enter a recirculation mode following a LOCA and contain insulation which could present a potential blockage problem.

Vortex formation is not considered a serious concern because of the large size of the suppression pool and the consequent low approach velocities.

Accordingly, a smaller portion of this program will address only the blockage concern for boiling water reactors.

2.

PLAN FOR PROBLEM RESOLUTION This Task Action Plan is designed to provide guidelines and requirements applicable to the various licensing stages while proceeding with gathering of additional information required to achieve resolution of this u

'9 solved safety issue. To accomplish these objectives, the work effort is ^. divided into the following subtasks:

(1) Summary of Recirculation Tests for PWRs (NRR)

(2) PWR Vortex Technology (NRR)

(3) Interim Plant Surveys (NRR)

(4) Experimental Studies of Sump Hydraulic Performance and Vortex Suppression Devices (DOE-Sandia/RES)

(5) Identification and Characterization of Insulation (s) Used in Representative Plants (RES)

-(6) Estimation of Insulation Debris Resulting from Reactor Coolant Pipe Breaks (RES)

(7) Estimation of Debris Distribution within PWR Containments (RES)

(8) Assessment of Debris Motion During the Recirculation Mode (RES)

(9) Assessment of Tolerance of Safety Systems to Debris (RES)

(10) Development of Safety Evaluation Criteria, Implementation Documents, l

Design Guides, etc. required to resolve safety issue (NRR)

These subtasks are detailed below. The Offices with lead responsibility for carrying out and implementing these subtasks are indicated within the parentheses.

The responsibility for resolution of this safety issue rests with NRR.

In orde to best utilize NRC's capabilities and resources, these efforts will involve both NRR and RES staff, and subcontracted efforts.

RES/RSR will serve as the Task Action Plan manager and will assume responsibility to develop work plans for subcontracting for and managing Subtasks 4, 5, 6, 7, 8 and 9.

NRR will provide for overall technical cognizance, establish-ment of informational (or technical) requirements, and the review and assessment informational adequacy of Subtasks 4, 5, 6, 7, 8 and 9.

NRR's principal effort will be initially directed at completing Subtasks 1, 2, t

and 3', and at a later date to concluding Task 10 (e.g., development of evaluation and design criteria, guides and resolution of the safety issue).

i 2

- - -. - -...~

~,

l-

s d

Subtask Descriotions Subtask 1:

Su. mary of Recirculation Tests for PWR's The objective.of this subtask is to document NRC experience in reviewing sump tests completed and to identify ' current interpretation of applicable Regulatory Guides.

A NUREG report on this topic is scheduled to be issued in. August 1981. This report will supplement current OL review practices.

Subtask 2:

PWR Vortex Technology l

Information and experience gained through plant sump tests has been

~

summarized by the University of Iowa (Contract No. NRC-03-078-130) in a final draft report "PWR Vortex Technology".

This report will be issued as a NUREG report and will supplement requirements set forth in Regulatory Guide 1.82 for CP and OL review activities.

The Iowa Report and the report resulting from Subtask I will document the current experience and technology base.

Subtask 3:

Interim Plant Surveys The subtask will be initiated by NRR. A letter will be sent to several operating PWRs, generally licensed before 1975, requesting water sump and insulation information. The responses should provide plant specific data

~

on sump location and design, and insulation utilized within containment.

The sump and insulation information received will extend the survey undertaken under Subtask 5 and provice a data base for better assessing the significance of potential debris.

Subtask 4:

Exoerimental Studies of Sume Hydraulic. Design and Vortex Suporession Devices This Subtask is directed at obtaining experimental data to determine:'(a) the interrelationships and relative importance of sump flow and geometric design parameters on the hydraulic performance of containment recirculation sumps, and (b) examine the effective range of vortex suppression devices.

A OCE-sponsored program (on behalf of NRC) has been subcontracted to Alden Research Laboratory thru the Sandia Laboratories. This is an experimental program designed to pursue two principal areas. The first area is the effect of various sump design parameters on the inception of vortices and the experimental data obtained will provide a basis for evaluating containment sumps in older PWRs and formulation of recommended sump design criteria for new plants. The second principal area will be the evaluation of various vortex suppression techniques to identify their l

range of application. The Alden program and work scope is based on NRR's developed requirements and selection of contractor.

t TheAhdenprogramwasinitiatedinJuly1979;facilityshakedowntesting was completed in August 1980; and the program is currently scheduled to complete '.esting in August 1982.

a i

3

.e -

~

y Identification and Characterization of Insulatier. Used in Subt.ask 5:

Re::resentative Plan.s i

l and This subtask wil1 survey and document the types, amounts, chem ca f insulation eechanical properties, mounting mechanisms and location oTwelve reference pl currently utilized within reactor containments.

BWRs) and the appro-h will be selected for this stucy (nine PWRs and t ree i

i plant drawings priate tabulations, material summations and descr pt veThe type ceveloced.

and manufacturer.

i informa-Contact will be made with the respective plant owners to obta n I

i ill be made to tion related to insulation used and some site vis ts w obtain confirmation of data received.

i ived will As indicated in Subtask 3, the operating plant informat on recewill provide a c i

extend the data base and the combined informat on debris under l

tion of insulation utilized within containment to generateThis then prev i

described below.

large LOCA conditions.

the necessity of undertaking Subtasks 6, 7, 8 and 9 as Estimation of Ouantity and Nature of Insulation Debris Subtask 6:

Resultinc from Pice Breaks d nature Engineering antlyses will be undertaken to estimate the amount an l

i by fracture, of insulation displaced from breaking primary, system p pes 1

It is expected that initial analysess of insulation debris pipe whip and hydraulic forces.will provide bounding values as to amoun i

generated at the postulated break loc &tions.

i type of insula-determinations; of the displacement and break up of a g venl pipe break, pipe tion material would include the nature of the initia The displacement l effects.

whip, jet effects, and subsequent environmentaof insulatfor.

tulated pipe break location will also be estimated.

The results break locations will be utilized for the initial analyses.

i ed by NRR technical staff before proceeding into more ex l tical The estimated costs programs or supplecental experimental programs.

ffort) shown in Section 5 assume a follow up effort (or a two phase e of LOCA being required to conclude estimates of the quantity and nature l

generated insulation debris.

Estimation of Debris Distribution within the Containme Subtask 7:

developed Given the resul s of Subta'sks 5 and 6, predictive methods will be d debris within the to estimate the spatial distribution of LOCA-generateThis effort will be undertaken w d sample calcula-containment prior to recirculation.

the first chhse being development of analysis methods anility by NRR staff.

.lons, these results then being reviewed for acceptab i imum The second phase will apply the analysis to break locations for a m n number of representative plants.

4 99

• M.

,, ~

_m

L i

Assessment of Debris Motion and Redistribution Dur ne Subtask 8:

Recirculation ill address Based on the results of Subtasks 3, 5, 6 and 7, this effort w l

i mode. Engineering the redistribution of debris during the recircu at on i

hich might-estimates will be made of the type, a'nd amount of, debr s w fety systems.

block approach paths, sump screens, and penetrate t istics is included in the costs contained in Section 5.

lt Guide 1.82 50 percent blockage assumption set forth currently in Regu a ory i for this is deemed necessary, Subtasks 6 thru 8 will provide the bas s determination.

Debris Assessment of Tclerance of Safety Systems and Core to Subtask 9:

k 5, 6, 7, This subtask will utilize information developed under Subtas s) of safe and 8 will adt.ress the susceptibility (or toleranceA description of anticipated esentative entrained debris drawn from the sump. debris, and attendant LO bility, and life plants and an assessment of component and system operaThe po wi-11 be carried out.

part of this subtask.

tially, It :hould be noted that Subtasks 6, 7 & 8 would be undertaken s with the proceeding tasks providing information for Develcoment of Safety Evaluation Criteria, Imolementatio ncted.

Docume_nts, Desien and REG Guides Recuired to Resolve Subtask 10:

Safety Issue issue cannot be Although all end products r* quired to resolve this cted.

ddressing Recommendations for a new or revised Regulatory Guide a 1) tional sump design.

Recommendations for a new or revised Regulatory Guide f 2) sump testing.

l tion Recommendations for a new Regulatory Guide addressing insu

[

3) usage inside containment.

i Criteria fpr the reevaluation of containment sumps in operat n 4) reactors.

Reyisions and/or additions to current Standard Review Pla d

5)

A final NUREG report providing the staff's safety evaluation a i ed safety conclusions regarding resolution of this currently unreto v 6) issue.

a

,..,,,,. ~. - -, - -. -. -. +

2.

--=~-.-.--.-,,--,,m...---.,~

.m.,w..---.,,.y.v--..

l

\\

3.

BASIS FOR CONTINUED OPERATION AND LICENSING PENDING COMPLETION OF PROGRAM The perfor=ance of containment emergency sumps for plants under review is determined from the evaluation of, successful completion of preoperational test 1;' performed in conformance of REG Guide 1.79, and the application of guidelines set forth in REG Guide 1.52 Over the past years (since 1974), the NRC staff has developed increasing confidencs in the applicability of thorough preoperational recirculation tests.

This experience is being documented (see Subtask (1)) and will be utilized in licensing evaluations and to provide a technical basis for this program.

In addition, there are limits (such as the 50 percent blockage criteria) taken from existing REG Guides, which will be reevaluated as a result of this program.

Therefore, preoperational testing will continue to be relicd upon for demonstration of adequate hydraulic performance of emergency sumps and

~

recirculation pumps prior to issuance of operating licenses for new plants.

However, the sump designs of older plants (pre-1974 OL issuance) were not tested in accordance with Regulatory Guide 1.79 or evaluated against the criteria specified in Regulatory Guide 1.82.

Therefore, the situation with respect to continued plant operation can be viewed as:

(a) currently operating plants, (b) plants approaching or having recently received operating licenses and (c) plants approaching the CP stage. The related actions are as follows:

3.1 Currently Operating PWRs -

Operating PWRs, which have not been tested for adequate NPSH and i

vortex control, may be subject to cavitat kn or vortex formation.

l To obtain test data for these containment sump configurations, a series of full scale tests is being performed at the Alden Research Laboratory under Subtask 4.

Preliminary results from this test program indicate that even though a severe vortex may be formed for some test configurations, the amount of air entrained in the recir-culation pipe results in a void fraction of less than 5 percent.

Typical air water pump performance tests indicate that potential pump flow degradation under these conditions would be minimal. In view of the favorable results indicated by the test data obtained thus far, continued operation is justified pending completion of the preliminary test program.

A systematic review of the initial Alden test series (approximately 25 configurations) is planned for early 1981.

These initial tests will include a preliminary assessment of typical vortex suppression devices. The data obtained in this test series will be examined specifically for any potentially significant inadequacies with respect to sump designs in operating plants.

3. 2 PWRs Approaching OL, or Having Recently Received an OL It is our judgement that plants in the OL review stage, or having recently received an OL, have demonstrated adequate sump performance through preoperational tests as described above, and that the perti-nent requirements of REG Guide 1.82 have been met.

6 i

i l

6 l tion employed, the staf f dith respect to the amounts and tyees of insu able of being trans;orted to considers all materials which might be capa ificant blockage of the the sump such that the potential for s gnWith regard to other potential i

i ns are required to containment sump screens is precluded. sources of ceDris detect occurrences of degraded m'aterials.

PWRs Approaching CP Stage tests has identified a 3.3 Licensing staff experience with recirculationnumoer o i h could occur (e.g.

The vortex formation, need for vertex suppress o be provided to applicants reports resulting from Subtasks 1 and 2 willin the CP i

d accordingly.

insulation In addition, applicants will be requested to reviewCA effects on gene utilized within containment, assess LOdebris, and to evalu stems during the recirculation mode.

BWR Containment Considerations the concern addressed 3.4 i

With regard to SVR containment and ECCS des gns,tential for degraded by this task Action Plan is limited to the po llowing a LOCA.

ECCS performance as a result insulation debris d considered i

quantitatively relative to debris result ng-breaks.

i

- even if some This concern is not adjudged to be significant s nce i lihood of any insulation did reach the suppression pool, the l ke is very small.

is typically The reason is that suction piping to ECCS systemsl l t d approach

~

velocities c'e very low, thereby permittingIn addition, BWR designs employ str float on the. pool surface.

PSH calculations for RHR pumps are within pump suction piping, and N based on an assumed 50 percent blockage. f BWRs is acceptable Accordingly, continued licensing and operation o pending completion of this program.

NRC TECHNICAL ORGANIZATIONS INVOLVED Research Branch of 4.0 TAPA-43hasbeehassignedtotheSeparateEffectsThe Task f Subtasks 4, 5, 6, 7, 8 and 9 as described in Section 2. Reviewer ible for the conduct RES/RSR.

of Subtasks 1, 2, 3 and 10.

I l

7

~

z

. -. - -. ~

4.

NRR Technical Organizations Involved The following NRR branches will provide technical support and input:

(Estimates in. man-months)

FY 81 FY 82 FY 83 Generic Issues Branch (GIB) 1.0

1. 0

1. 2 Reactor Systems Branch (RSB) 2.0

2. 0 2.5 Containment Systems Branch (OSB)*

1.0 1.0

1. 0 Mechanical Engineering Branch (MEB)*

1.0

1. 0

1. 0 The principal functions that assigned individuals will be required to provide are: provide problem definition and technical requirements, write interim and final guides and criteria, review technical findings and analyses obtained from subcontracted effort, determine technical acceptability of derived analysis techniques and limiting calculations, etc. Assigned staff will also be members of the TAP A-43 Technical Review Group. NRR' staff will also be responsible for performing the effort described under Subtasks 1, 2, 3 and 10.

4.2 RES Technical Organizations Involved Technical support will be provided by RSR and Sandia Laboratories:

(Estimates in man-months)

FY 81 FY 82 FY 83

~

Reactor Safety Research**

10 8

8 l

Sandia 24 30 30 The RE5 branches shown above will provide A-43 Technical Review l

Group members and assist the Task Manager in planning effort for, and evaluating results obtained, under Tasks 4, 5, 6, 7,' 8 and 9.

l ATnis effort will be substantially reduced if Subtasks 6-9 are not necessary.

• • RSR support will come principally from the Separate Effects Research Branch; they will call upon Metallurgy and Materials Branch and Mechanical Engineering Research Branch as required.

t S

e i

l 8

i

s 5.0 TECHNICAL ASSISTANCE The estimatad costs associated with Subtasks 4, 5, 6, 7, 8 and 9 are shown in Table 1 and include the contingencies noted.

Should extensive analyses and/or experimental effort be required to substantiate findings.

regarding debris generation, and/or distribution of debris, a very signif-icant cost increase will take place.

Such costs are riot included in the cost estimates shown in Table 1: The total estimated NRC subcontracted effort costs are as follows:

l FY 19S0 FY 1981 FY 1982 FY 1953 185,000 365,000 215,000 150,000 Assuming the absence of major analysis and experimental effort required for debris generation estimation, it appears that A-43 should be concluded in September 1983.

j Subtask 4, is currently under contract through DOE-Sandia, and it is expected that Subtasks 5, 6, 7, 8 and 9 will be subcontracted through existing RES contracts or National Labs, if possible.

Since the majority of subtasks are related to insulation employed, and the effects of LOCA generated debris on containment emergency sumps, use of industrial cont'ac-l tors knowledgeable in containment and reactor equipraent design and installa-tion (such as AEs) would be the most cost beneficial to the Government -

as opposed to National Laboratories with limited experience in these areas.

Sandia,inadditiontomanagingthehidensumphydraulicsresearchprogram, will provide the NRC with independent data analysis and evaluation capa-bility, plus assistance in developing information for use in precaring design guides and evaluation criteria.

The Alden effort and Sanoia technical assistance efforts are detailed below.

A.

Contractor: Alden Research Laboratory Funds Required:

$200K FY 1979; $742K FY 1980; $500K FY 1981;

$600K FY 1982 This contract is a 00E funded (on behalf of the NRC) experimental program which is under way at Aldea Research Laboratory and addresses the issue of adequate sump or suppression pool fure-tioning in the recirculation mode. The objective of that work is to provide the data neeced to develop criteria for design, testing and evaluation of plant sumps.

Parametric tests will be conducted at Alden to identify regimes where vortex formation or air entrainment present potential problems for sump pump performance.

The second portion of the Alden program is to develop vortex suppression techniques. This work will focus on those plant geometries found to be marginal when compared with the data base developed in the initial testing phase.

9 i

..=

s TABLE 1 6, 7, 8 and 9 ESTIMATED COSTS FOR TASKS 1, 2, 3, 4, 5, (Costs in Thcusands of O'ollars)

FY 1981 FY 1982 FY 198_3 FY 1979 g 1980 18 600 etasks 1 & 2 (Iowa Study) 500

~

742 200

- abtask 4 (Alden Contract) 65 85 i ation) udtask 5 (Insulation Character z

)

} 85 iubtssk 6 (Est. of Debris Generation i )

Subtask 7 (Est. of Debris Distribut on 45

)

65 Subtask 8 (Assessment of Debris Motion

)

Subtask 9 (Tolerance of Safety System 715

~

~

0 665

~

807 218 150 150 Subtask Totals 150 120 0

150~

815 865 Sandia Technical Assistance 927 TAP-43 Total 365(Est) 215(Est) 150(est) 218 185 0

18 400(Est) 500(Est)

NRC Funding Requirements 742 2C?

DOE Funding Requirements O

c O

i s -

10 -

e e 4

~hw-.%

---+w-e--

-#wr y

.,w-w

%-A e

--e-o-m--e w

---

e.re---wy--y e

--w,e--

v

-w y

4 4w'e pg-

+*e w-v' y

awg

-we

-w g

y--.gg.

eryey-v 'er t vw -

gr'T-7t--'

W---~

v't-w

.~

j i

)

D l

Sump testing started in August 1980 with completion of experiments estimated to be August 1982; a final report is scheduled for mic-1983.

j l

B.

Contractor:

Sandia Laboratories

, Funds Required:

$120K FY 1980:.$150K FY 1981; $150K FY 1982, $150K FY 1983 1

This is a technical assistance contract, wherein Sendia staff will work with Alden staff to establish a satisfactory data base, evaluate results being obtained, and carryout independent data analyses.

Also, Sandia will assist in preparation of technical data for use in criteria for avoidance of vortex formation, air entrainment and recirculation pump inlet head degradation.

l In addition, use will be made of Sandia staff in subcontracting for,.

and evaluating results, obtained under Subtasks 5, 6, 7, 8 and 9.

6.

Interactions with Outside Orcanizations A.

Utilities Contacts will be made with utilities owning the " reference" plants selected for the generic insulation survey described in Subtask 5.

The generic plant information will be acquired on a cooperative basis without resorting to formal request for information. The results of this generic survey (carried out with the assistance of Burns and Roe) will be used for estimating debris generation and potential effects on long term cooling.

i B.

Advisory Committee on Reactor Safeguards These A-43 activities will be coordinated with the appropriate ACRS subcommittee.

Significant information will be provided to the subcommittee as it becomes available and meetings will be scheduled at appropriate times as the task progresses.

7.0 ASSISTANCE REQUIRED FRCM OTHER NRC OFFICES A.

The Office of Inspection and Enforcement A liaison will be established with I&E and a request for I&Es involve-i l

ment will be formulated. Their aid in arranging for site visits, development and preparation of recirculation test criteria, and development, of evaluation criteria for operating plants is expected.

B.

Office of Standards The guidance and assistance of this office will be utilized in implementing the results of this program by preparin.g REG Guides.

l l

l I

11'

\\

..~

.o S.

POTENTIAL PRCBLEMS 8.1 The principal potential proolem is limited funding resources required to carry out subtasks 6, 7, 8 and 9 if these are determined to be required following concluding Subtasks 3 and 5.

The costs shown in Table 1, represent current estimates assuming early achievement of adequate analysis ~

sodels and that a limited numoer of plants will be adequate for arriving at meaningful conclusions.

Should the initial results of subtask 6 and 7 show a strong plant specift: dependence, then decisions will have to be made regarding continuing a generic evaluation, or pursuing a plant specific evaluation.

8.2 Performance of subtasks 1 thru 3 by NRR will require participation from members of DSI and OL over the next several months.

Unconditional assign-ment of selected personnel will be required.

8.3 Subtasks 6 thro,;h 9 represent the development of new analyses deemed necessary to sug aort, verify, or correct current practices and recommenda-tions.

Some of.hese subtasks (or elements thereof) may be difficult to model and could grow excessively unless carefully planned in advance and then constrained to the minimum necessary to resolve the safety issue.

This will require work scope definition in advance, and NRR acceptance before the e# fort is undertaken.

This poses a potential scheoule impact due to the time required to obtain NRR concurrence on the work plans for Subtasks 6, 7, 8 and 9.

Y e

s i

12 L-2-

e-

-,r

-y-w-w-

y-w w-w

--m

,--e wew

'w-p-

-,~e wr*-------

-,-e y

y-w---

r y

---

y,

-