ML20054G582

Responds to 820512 Memo Re Control of Occupational Doses by Prevention of Transport & Buildup of Radioactive Crud,By Removal of Radionuclide Deposits & Minimization of Failure of Major Plant Components

ML20054G582
Person / Time
Site:	Palo Verde, 05000000, 05000470
Issue date:	06/15/1982
From:	Dircks W NRC OFFICE OF THE EXECUTIVE DIRECTOR FOR OPERATIONS (EDO)
To:	Shewmon P Advisory Committee on Reactor Safeguards
Shared Package
ML20054G583	List: ML20054G582 ML20054G587
References
NUDOCS 8206220085
Download: ML20054G582 (15)

Text

~,

[, kh{ %

DISTRIBUTION:

. . 4 g Y *, Central R_ading W le '

( () / O ' - p DEis:nhut

/ ,g" '('O (f.'y NRR Reading File SHanauer 9 , ;) J' EDO Reading File RVollmer i> '

RAB Reading File PCheck NRC PDR-w/ incoming BSnyder M 151982 LPDR-w/ incoming RJMattson PPAS RWHouston HRDenton EGCase

)e s

FJCongel CYChang WJDircks VBenaroya Dr. Paul S. Sheunon, Chairnan KCornell DMCollins Advisory Comittee on Peactor Safeguards PRehm DMeyer U. S. Nuclear Regulatory Connission VStello SCavanaugh Uashington, D. C. 20555 RMinogue ED0#11863 CMichelson CPaul

Dear Dr. Sheunon:

RCunningham SECY (3)

EGoodwin This is in response to your nenerandun of ftay 12, 1982, concerning control of occupational doses by prevention of the transport and buildup of radioactive crud, by renoval of radionuclide deposits, and mininization of failure of najor plant components.

With regard to the earlier concern indicated in the referenced nenorandun of December 16, 1981, CESSAR-80/Palo Verde applicants have perfonaed occupational ALARA design reviews using NSSS, AE, and Arizona Public Service health physics and engineerino personnel. These reviews have been supplenented by onsite inspections during construction. These reviews and inspections were conducted usina th' reconnendations of Regulatory Guide 8.8, which includes provisions for the

• eduction of crud buildup, the renoval of cn3d deposits and the use of hiqh rel ability components. Examples of nore specific crud reduction /renoval and component reliability features incorporated into the plant include:

- ninirization of crevices, dead legs and valves at low points in piping,

- use of valves with flow characteristics that ninimize crud deposition,

- use of low cobalt materials in systens exposed to primary coolant except ubere hard erosion resistant surfaces are necessary.

- nrovisions for draining, flushing, and remotely cleaning or decontaninating equipnent and pipinq, ,

- use of hinh reliability naterials in the construction to inprove the prinary coolant systen component intenrity - such as ferritic stainless steels of the 400 type for stean generator tube supports to inprove tha tube integrity, ,

- innroved tecroal hydraulics to ninimize the propensity for the currently known f r

stean qenerator corrosion problems, '

,j

- nore restrictive stean generator chemistry control to ninimize corrosion problens, h

f L' 4

- coolant chmistry control to reduce corrosion and to nininize the production of \}~ [t i l

radioact1ve cru ! and deposition of the radioactive crud on out-of-core systen ,/

surfaces. l' [f$

_ 8206220085 820615 PDR ADOCK 05000470 A PDR .

sunism ) . .

om>

nne ronu m oa oei mcu caa OFFICIAL RECORD COPY usamm-nwm

Dr. P. S. Shewnon O The staff found that the Palo Verde applicants had proposed adequate design and controls to reduce radioactive crud and had incorporated high reliability equip-ment. Based on these and similar considerations by the applicants, the staff concluded that the applicants had provided reasonable assurance that occupational doses would be ALARA.

Other plants currently under licensing review have incorporated similar design features to improve component reliability, to reduce production and deposition of radioactive crud, and to facilitate decontamination. Additionally, these plants have proposed coolant chenistry control programs to reduce production and deposition of radioactive crud to minimize component failure. As a result of such design and chenistry control improvenents, these plants should not experience as pronounced a buildup of radioactive crud as older operating units, and the need for repair and/or replacement of najor components, such as BVR feedwater spargers and P1R stean generators, should be reduced.

With regard to nininizing occupational exposures at the operating plants, the staf f is not only sensitive to the need for licensees to implement the ALARA criterion, but we, in agreement with the Conmittee, also recognize the inportance of: preventing the buildup of radionuclide concentrations within the prinary cooling systen; reducing radionuclide buildups if preventive measures are not suitably successful; and having reliable corponents so that the need for repair /

naintenance is at a minimun. On the ALAPA principle, our present regulations state that licensees should nake every reasonable ef fort to maintain exposures as low as reasonably achievable. The staff has over the past two years sought to strengthen the radiation protection prograns of the licensees. liow, we are exploring core enforceable ways in which to achieve the desired results. Ue are also aware of an ongoing IMPO effort that seeks similar results.

On preventing buildup of radionuclides, we recognize that significant value can derive from more specific guidance to operating plants as to what chenistry control inprovements might he reasonably implemented. To this end we are considering the formulation of a progran to evaluate those operating procedure improvements, such as maintenance of proper pH, that have proven successful in reducing occupational dose and that can be reasonably implenented. An initial step in this direction is being taken by the Of fice of fluclear Regulatory Research to establish a contract to cssist in the identification of dose reducing plant inprovenents. He expect this effort and a contractor report to be com.pleted within a year.

omca > . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

sunmue > . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . ...

ouny . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ......... ... . . . . . . . . . . . . . ..

Nac rosu aia oo.8a nacu c2n OFFICIAL RECORD COPY uso m m i_. m m

f . .

^ r Dr. P. S. Shewnon _

With regard to reducing actifity that does accumulate, we are aware of a few cases where decontamination of nuclear plant systens and conponents has been performed prior to naintenance operations to reduce radiation levels. In those cases, decon-taminations have been effective in inplenenting ALARA since average decontamination factors of about 10 were achieved and 250 to 900 person-rens collective radiation exposures were saved during each of the naintenance operations. Both NRC and indus-try are conducting decontamination research prograns. NRC has Brookhaven Hational Laboratory under contract to investigate decontamination impacts on solidification and waste disposal, and Battelle Northwest LaDoratory is studying decontanination effectiveness and its impact on occupational exposure reduction.

On the reliability of components, it would appear, from an economics viewpoint alone, that the industry should seek cost-effective inprovenents in reliability of their equipment on their own rather than through further NRC requirenents. For example, approxinately 23 percent of non-refueling outage tine has been attributed to steam generator degradation. Nonetheless, because of safety considerations, we do have an onqoing program to investigate ways in which the reliability of stean generators can be enhanced. Further, the National Reliability Evaluation Progran should contribute to a better identification of corponents having relatively high naintenance/ failure rates.

In sunnary, we have initiated actions to assure that plants currently under licensing review, including CESSAR-80/Palo Verde, have incorporated plant equipment and operat-inq programs including high reliabiliy equipnent and radioactive crud reduction and renoval. For operating plants that initially did not include such consideration, we

! have in progress actions expected to result in each licensee establishing an internal review program to consider such improvenents, and actions to identify and promulgate specific inprovenents to reduce workers' doses. He will keep you informed of our progress on these activities and welcome your connents and assistance as we proceed.

Si ncerely, (SignesWilliam L Direks l

i Willian J. Dircks Executive Director for Operations l

• ELD TSB:PPAS

• EGoodwin ED0 leh

• IIJUTi'cks

• SEE PREVIOUS PAGE FOR CONCURRENCE 06/10/82 06/10/82 06//4 /82 D S,,I. ,:R AB.,, . . DS. ,1,; R AB,,,,,,,,, ,E NG, : MT,E,B, ,, ,,ENG ;CMEB , , , DS I : ADR,P,,,, ,, ,, D S ,ILD,,,,, ,,, ,,

,, f@ R,, ,, ,,, , ,,, ,,,

omca> , ,

su,mme > *.DMca).1. ins.:sj

• f.J CongeJ....... *.M bang..... *.XhnAr914..... *Etlaustan.. . *RJMa.t.tson.... *HRDen. ton......

om> .06/.m/82.. . 06/.10/.R...... .. 95L1.0/.M.. .. .Q6L1.Q/E.. ... .9.61.10/.E...... . 05H0/E...... . 0.61.10/M... ..

unc ronu ais 00% nacu oua OFFICIAL RECORD COPY usceoam-uwa

• %- ~.

N\

\

Or. P. S NSh ewnon s

\[ \

Mith regard to' reducing activity that does accunulate, we are aware of a few cases where decontanination of nuclear plant systens and components has been perforned prior to naintenancesoperations to reduce radiation levels. In those cases, decon-taminations have been'ef fective in inplementing ALARA since average decontamination factors of about 10 were achieved and 250 to 400 person-rens collective radiation exposures were saved during each of the naintenance operations. Both HRC and indus-try are conducting decontamination research prograns. HRC has Brookhaven National 1.aboratory under contract.to investigate decontamination inpacts on solidification and waste disposal, and Battelle Northwest Laboratory is studying decontanination effectiveness and its inpact on occupational exposure reduction.

On the reliability of components, it would appear, from an economics viewpoint alone, that the industry should sock cost-ef fective improvenents in reliability of their equipnent on their own rather than through further !!RC requirements. For example, approximately 23 percent of non-refueling outage time has been attributed to stean generator degradation. Nonetheless, because of safety considerations, we do have an ongoing progran to investigate ways in which the reliability of stean generators can be enhanced. Further, the National Reliability Evaluatinn Progran should contribute to a better identification of conponents having relatively high naintenance/ failure ra tes. N

\

In sunnary, we have initiated actions to assurkthat plants currently under licensing review, including CESSAR-80/Palo Verde, have incorporated plant equipnent and opera-ting prograns including high reliabiliy equipnent Knd radioactive crud reduction and renoval. For operating plants that initially did not, include such consideration, we have in progress actions exnected to result in each liqensee establishinq an internal review proqran to consider such inprmierents, and actichs to identify and proraulgate specific inprovenents to reduce workers' doses. We will' keep you infomed of our progress on these activities and welcome your coments and assistance as we proceed.

Sincerely, -s N

's '

N Hillian J. Dircks Executive Director for Operations N

.$i' ELD TSB:PPAS EDO

• EGoodwin 7JUircks ASEE PREVIOUS PAGE FOR CONCURRENCE 06/08/82 06/08/82 06/ /82 LfAr. , , rs ta orncry .D.SI.; rah . . 0.S.I.;. RAS.... ..E.NG ;MTJ B..' .JNG :.CMER.. . Ok hh.[ . . D.S (:M. ..NRR ...

SURNAME) ,,,

,",9, ,

• CYChang, *VBenaroya R W on RJ dtjso,n, t *HRD _ ,

o n,,,,,,

ome) .0RLOA/A2... .06/03/p2, 06/08/#2.. .06/08/82.. . 06/..h, 2.. .041. L8.R.

. 05/$62.. ..

Mc ronu ais o0 eci Nncu om OFFICIAL RECORD COPY usw ,wmw

Dr. P. '. Shewmon The staf f found that the Palo Verrio arnlicants bad proposed adequate design and controls to reduce radioactive crud and had incorporated hich reliability eouio-

,e r + . Cased on thest and similar considerations by the applicants, the staf f i cnncluded that t.b e an91trants had provided reasonable assurance that occunational l doses woold he nL AP A.

Ptber plant s curren+1y under licensino review bave incarnorated similar desian S ea tu rns to ir'orove component reli abili ty , to reduce production and deposition of radioac t ive c ru i, and to f acilitate decontamination. Ad di tio nal l y , these olants have nrnnosed enolant chemi stry control procrans to reduco production and donosition of radioactive crud in minimize corponent failu"c. As a result of such 4 5i00 dr/ Chemi strV Control if1proVements, these olants shoul d not exnerience

." pronouncr<' a buil dup of radioactive c rud as older operatino units, and the need

'er renair and/nr replacement of oajor co-'conents, such as WP feedwa ter s na rne rs ana N s te v annera to rs , shoul d be reduced.

'ec ont r'i ra t in ns at nuclr ar plant systems and cor'ponents have been perforned prinr

+a victonanco nnerat. ions to reduco rarit ction level s. Thase decontaninations have he r n eitortive in imolcrontina ALVA since averaqe decontanination f actors of A no t l' .r rn vh ievr d a n<' '"50 to W1 no rson-rens collect ive radi ation e)rnesures worn s av N durinc PaCh of th0 ' 'a i n ten a nC6 ODorations. noth $C a nfi i ndustry are c on inc+ ino ir < nnt ri na + inn rosearch nrnarars. W C has n ront have n "a tional labora-t ' rv under ( nn+ ract +a i nves ti na te Ancent ami natinn innact s on solidi fication and olste d i snOS /'l , 3 rd M a tt elle Onrt hypg t Laborato ry is studyinc deconta.mi nation ef feC-ti;or% s and i t s ir'DaCT or DCCurS tional eWPsure reduc +100 a- r or ^ r n i r *N t si nni fic 'nt valu9 can de rive f ron nn er, sneri fic nui da nce to

-)n a rl ? i n ' O l l ' ' * '. :l e. to tha* ChW d s tr'/ Cont rol led 9 t ')Ti 31 s i P r W e ne nt S Minh t he r f'? s P nal'l v i 'n l t N D n

• C . T ') this end we are cons ideri nc; the f orul a tino of ti o rn"r r tn ov il u a t e. tbnSP 4 siqn ch a nnes , suCh d s renl aCc'e nt Of condenser f one r D P ,

te.61..s, i r,d enoratioq nrecpagen j prnypopqts, such x main +enar*(,o e O r t lia + 1 ave i r nv e n St;Censsfq!1 jq redyrinn OCCuPAtinnal # Dsp and

• hat can he rp3sgnably iinla ent M. An initial s te' i n this di rnetion i s keinq t .* n n h v t bo rt fice of o

ncl.or inla ter/ "escarch to ns t ab l i sh a contract to assist i n + Pe i de nti fica

• ion

• f those doce rv<urir cl a nt i mp r ov e.p nt s. se ov, noct this effnri and a Cont ract o r r + c n et to he cw'olr+0a '"DMCo.l.l. ins.:sj'fJfong.el., ,,,,,G,Y.Ch,ang " ~" VBenaroya

0. 5../.2 8../..B.i. ..., , ',EEEEElEE",,~~05728782"'"

'UE')EE')E2"" ' '"05728782'"

un> 0512BlB2... ., , 95L281.8.2.... .... . , , , , , , . , , , , , , . . . . . , . , , , , . . , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , ,

nac ronu ais oo-aomacu o:4o , OFFICIAL RECORD COPY usom ini-esse

y

.a  :

Dr. P. S. Shotoon The s taf f found that the Palo Verde applicants had pronosed adequate desian and controls to raduce radioactive crud and had incorocrated hiqh reliability equip-

te nt . nased on these and similar consideratiens bv the applicants, the staf f concluded tha t the anplicants had provided reasonable assurance that occupational dnses woul d he ALMA.

Ot her ni ants currentl y under licensinq review have incorporated similar desion features to irnrove component reliabili ty, to reduce production and deposition of radioac tive c rud, and to f acili tate decontanination. Additionallv, these plants have pronosed conlant chenistry control proqrans to reduce production and deposition of radioactive crud to mininize conponent failure. As a result of such desian and chemistry control improvements, these plants should not experience as nronounced a buildon of radioactive crud as older operating units, and the need for renair and/or replacament of najor conconents, such as MlP feedwater spargers and nun s tean oe nera to rs , s hou l d he red uc ed.

hith reoard to operatino olants, the staf f is reconnendina a proposed rule, expec+ca tc he oublished wi thin the next two nonths, that woul d require all plants te innlerent an occ.unatienal AL AP A-inteqrated radi ation protection pronram. This rulo i- expected to rnsult in licensees establishinq internal review systens to ov al ua te and imnlement occonational dose reduction tecbninues and cmoonent relia-oilitv imrovo ent s. The staf f bas al so published draf t 'H!nr40761, " Radiation Prnt< ction Plans for t uclear Power Deactor Licensees," which nrovided pronosed hPR st W posi tions reqardi nc ?L APA.

i ec onta iinatinns of nuclear plant systens and cTinonents have heer perfomed prior t o ' v i n t e n a nc e ene r a t i e ns to ra<duco radi ation l evel s. These decontaninations have been of frc t iva in imnlementinc AL' IPA since average decontanination f actors of ahnu+ 14 were achiaved and Ma to 400 rerson-rens collective radiation exposures

' m re saved durinc each of the naintenance operations, no th 'PC and industrv are c onder t i nn decontanina+1cn researcF arocrams. MPC has Brookhaven ';a tio nal L ab ora-tnrv un 'er contract to investicate decontanination inpacts on solidification and waste disnesal, and "a ttelle ': ort hwest Laboratory i s studyinq docnntamination ef fec-t ivenesn and i ts innact on occonational exnosure reduction.

1

e rncooni ze that si nri ficant v al ue c an derive f rom mo re spec i fi c qui d a nce to oneratino nl ants as to ', hat cher'istrv control and ,aterials inorovecents niobt he raasonabls innlemonted. To this end we ire considrino the fornelation of a orn-ran to ev al uate those desian chanons, such as renlaceront of condenser tubes, 10d neeratinq procedure l'pf rN erents, suCh as PaintenanCe of orO*'er 0',

t ha t h aves n rnven suCCessf ul in reduciqu occuna t ional dose and that Can he reasonably

.-~- ..

.- L q:

\

. P. S. Shewnon innleneNted. An initial step in this direction is being taken by the Office of Huclear I?ggulatory Research to establish a contract to assist in the identification of these d6ec reducing plant inprovenents. We expect this effort and a contractor report to bek .anpleted within a year.

In sunnary, we Ave initiated actions to assure that plants currently under licensing review,\{ncluding CESSAR-80/Palo Verde, have incorporatmi plant equipment and operating progres including high reliability equipment and radioactive crud reduction and renovalg For operating plants that initially did not include such consideration, we haven n progress actions expected to result in each licensee establishing an internal eview proqran to consider such inprovenents, and actions to identify and orcrtulpate pecific improvenents to reduce workers' doses. He will keep you infc.aed of ottr progress on these activities and welcone your concents ,

and assistance as we proceed.

Sincerely, Mil ~(an J. Dircks Execu ive Director for Operations DISTRIBUTION:

Central Reading File CYChang NRR Reading File VBenaroya EDO Reading File DMCollins RAB Reading File DMeyer NRC PDR-w/ incoming SCavanaugh-E00#ll863 LPDR-w/ incoming CPaul PPAS SECY (3)

HRDenton EGoodwin EGCase WJDircks KCornell PRehm VStello RMinogue CMichelson RCunningham DEisenhut SHanauer RVollmer PCheck BSnyder g, RJMattson

• TSB:PPAS RWHouston EDO\

EGoodwin i /\ EJUirqks FJCongel . 05/27/82 9\ 05/ /82

• SEE PREVIOUS PAGE FOR CONCURRENCE \

..QShRAR., . ..EtlG:ET.Ea.. ..E.({G..:,C(iE.8,, ,.D S.I,:. ADR P,, .QSl;p,,,, .,({R, omcr > 0.S.I.:RAE.. ,,

sunuwc ) D:.ical.li.ns sj *.F.JCongel.. *CY. Chang...

. *V.aenar.oya..

. *RWHoustan.... .*RJm.t.t.s.on.. ..H on .

omy 05,/,2 Z/82,. . 0,5/2Z/82,. . 0 5/.R7./.8R.. . 05/22/82... . 05/22/82.... . . 05/27./.32... ..I 7..k.5 nac ronu us m-m nacu om OFFICIAL RECORD COPY uso m issi- m m

\ .

Dr. Paul S.\ ewnon h

Chairman Advisory Connit e on Reactor Safeguards U. S. t!uclear Reg latory Connission Washington, D. C. 0555

Dear fir. Shewmon:

This is in response to you nenorandun of tiay 12, 1982, concerning control of occupational doses by prevenyon of the transport and buildup of radioactive crud, by renoval of radionucliW deposits, and ninimization of failure of najor plant components. \

Mith regard to the earlier concern i icated in the referenced nenorandun of Decenber 16, 1931, CESSAR-80/Palo Verdb applicants have perfomed occupational ALARA design reviews using f1SSS, AE, andhrizona Public Service health physics and engineering personnel. These reviews have been supplenented by onsite inspections during construction. These revibus and inspections were conducted using the reconnendations of Regulatory Guide R,8, which includes provisions for the reduction of crud buildup, the renoval of crud s deposits and the use of high reliability conponents. Exanples of nore specific crud reduction /rceval and component reliability features incorporated into the plant include:

- nininization of crevices, dead legs and valves at low .oints in piping,

- use of valves with flow characteristics that ntninize crud deposition, N

- use of law cobalt natorials in systens exposed to primary coobnt except where hard erosion resistant surfaces are necessary.

- provisions for draining, flushing, and renotely cleaning or decont inating equipnent and piping,

- use of high reliability materials in the construction to inprove the pr r coolant systen conponent integrity - such as ferritic stainless steels of \ybe 400 type for stean generator tube supports to inprove the tube integrity,

- inproved thernal hydraulics to nininize the propensity for the currently known stean generator corrosion problens,

- nore restrictive steam generator chemistry control to nininize corrosion problems.

- coolant cheaistry control to reduce corrosion and to ntninize the production of radioactive crud and deposition of the radioactive crud on out-of-core systen surfaces, omen y . . . ~ . . - - . .-~~ ~ - . - ~ - - **

sunn:.ne> . . . ~ . . . ~ . - . . . - ~ ~ . - . ~ ~ ~ ~ - ~

~ - ~ ~ ~ ~ ~ ~ - ~ ~ * * ~ ~ *"""*""""

ou,y . . . . ........... . . . . . . . . . . . ~" .~

unc ionu m om NHCM Om OFFICIAL RECORD COPY usa e-mo

f '

f.

V~

P. Shewnon The staff found that the Palo Verde applicants had proposed adequate design and controls to reduce radioactive crud and had incorporated high reliability eouip-nent. Based on these and similar considerations by the applicants, the sr:ff concluded that the applicants had provided reasonable assurance that occupational doses woul be ALARA.

Other plants' currently under licensing review have incorporated similar design features to inqrove conponent reliability, to reduce production and deposition of radioactive crub and to facilitate decontamination. Additionally, these plants have proposed coolant chemistry control programs to reduce production and deposMion of radioactive crud to ninimize component failure. As a result of such design and cheh1.stry control improvenents, these p1' ants should not experience as pronounced a buildup of radioactive crud as older operating units, and the need for repair and/or replacenent of major components, such as BWR feedwaer spargers and PWR steam generators, xshould be reduced.

With regard to operating plhnts, the staff is recommending a proposed rule.

expected to be published within the next two months, that would require all plants to inplement an occupational ALARA-integrated radiation protection program. This rule is expected to result in licensees establishing internal review systens to evaluate and implenent occupational dose reduction techniques and component relia-bility improvements. The staff has also published draft HUREG-0761, " Radiation Protection Plans for Nuclear Power Reactor Licensees," which prmided proposed flRR staff positions regarding ALARA. '

Oecontaninations of nuclear plant systens and components have been perfomed prior to naintenance operations to reduce radiation levels. These decontaminaions have been effective in implementing ALARA since average decontamination factors of about 10 were achieved and 250 to 900 person-rens collective radiation exposures were saved during each of the maintenance operations. Both flRC and industry are conducting decontanination research programs. !!RC has Brookhaven flational Labora-tory under contract to investigate decontamination impacts on solidification and waste disposal, and Battelle florthwest Laboratory is studying decontanination cffec-tiveness and its impact on occupational exposure reduction.

Uc recognize that significant value can derive from nore specific guidance to operating plants as to what chemistry control and materials improvements night be reasonably implenented. To this end we are considering the fornulation of a program to evaluate those design changes, such as replacement of condenser .

tubes, and operating procedure imprwements, such as maintenance of proper pit, that have proven successful in reducing occupational dose and that can-be reasonably OFFIC E ) .

SURNWE) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

DOTE ) .

Nac ronu m o>aopmcu ma OFFICIAL RECORD COPY usamm maa

. g P. Shewnon inplenented. An initial step in this direction is being taken by the Office of fluclear Regulatory Research to establish a contract to assist in the identification of these dose reducing plant inprovements. We expect this effort and a contractor report to be cocpleted within a year.

In sunnary, we have initiated actions to assure that plar os currently under licensing review, including CESSAR-80/Palo Verde, have incorporated plant equipnent and operating progre1s including high reliability equipnent and radioactive crud reduction and renoval. For operating plants that initially did not include such consideration, we have in progress actions expected to result in each licensee establishing an internal review progran to consider such improvements, and actions to identify and pronulgate specific improvements to reduce workers' doses. He will keep you informed of our progress on these activities and ucicone your connents and assistance as we proceed.

Si ncerely,

\lillian J. Dircks Executive Director for Operations DISTRIBUTION:

Central Reading File CYChang NRR Reading File VBenaroya ED0 Reading File DMCollins RAB Reading File DMeyer NRC PDR-w/ incoming SCavanaugh-ED0#11863 LPDR-w/ incoming CP ul PPAS S ECY HRDenton EGoodw(3) in EGCase WJDircks KCornell x PRehm VStello RMinogue CMichelson RCunningham DEisenhut SHanau er RVollmer PCheck BSnyd er

(

TSB AS EDO

-RJMattson EGoodwin WJDircks RWHouston 05/ /82 FJCongel *SEE PREVIOUS PAGE FOR CONCURRENCE 0542f/82 1 DI l T omen > DS..I;RSA n

DSI:RAB ENG:MTEB ENG:CMEB

. . . . . . . . . . ... \~ DSI:D..-- -

~..~. ~NRR

~ -- ~ ~ .-....~.

DMCollins:br *FJCong el *CYChang *VBenaroya R on *~RJMattson HRDenton

) 5..'. hbh~h,{_]hk ~-

"EElEElET~ ".UElE5lEE~^55/55/.55.~.'. .".. \

om> 'dE' EE')5E".

. .. . . . . . . . . . . . .. . . . . . . . . . . . . . . . . .. . '..b..ik.

5../. 5. 5..[.5. - --- -

l unc ronu m no em sacu mo OFFICIAL RECORD COPY es e au- mem

Dr. Paul S. hewmon Chairman Advisory Commi , tee on Reactor Safeguards U. S. Nuclear R' ulatory Commission Washington, D. C. 20555

Dear Mr. Shewnon:

This is in response to our memorandum of May 12, 1982, concerning control of occupational doses by prevention of the transport and buildup of radioactive crud, by renoval of radionuclidexdeposits, and minimization of failure of major plant compon ents. 'N With regard to the earlier co[fcern indicated in the referenced memorandum of December 16, 1981, CESSAR-80/Palo Verde applicants have performed occupational ALARA design reviews using NSSS, AE, and Arizona Public Service health physics and engineering personnel. These reviews have been supplanented by onsite inspections during construction. These reviews and inspections were conducted using the recommendations of Regulatory Guide 8.8, which includes provisions for the reduction of crud buildup, the renoval 'of crud deposits and the use of high relf ability components. Examples of mor'e s specific crud reduction / removal and com9onent reliability features incorporated into the plant include:

- minimization of crevices, dead legs and valves at low points in piping,

- use of valves with flow characteristics that minimize crud deposition, i

l - use of low cobalt materials in systens exposed to primary coolant except where l hard erosion resistant surfaces are necessary, x

\

l - provisions for draining, flushing , and renotely clea'ning or decontaminating l equipment and piping,

- use of high reliability materials in the construction to ' improve the primary coolant systen component integrity - such as ferritic stain 1ess steels of the _

400 type for steam generator tube supports to improve the tube integrity.

- improved thermal hydraulics to minimize the propensity for the currently known steam generator corrosior problems, 'N l

- more restrictive steam generator chenistry control to minimize corhosion probl eas,

- coolant cheatstry control to reduce corrosion and to minimize the production of l radioactive crud and deposition of the radioactive crud on out-of-core systen surfac es. 's w,,c) . .. .I. . . ..

l -> . . . . . . . . . . . ... . . .

, NRC FORM 313 00% NRCM Cm OFFICIAL RECORD COPY us w i m _ m u

E -

P. Shewmon The staff found that the Palo Verde applicants had proposed adequate design and controls to reduce radioactive crud and had incorporated high reliability equip-ment. Based on these and similar considerations by the applicants, the staff concluded that the applicants had provided reasonable assurance that occupational doses would be ALARA.

Other plants currently under licensing review have incorporated similar design features to improve component reliability, to reduce production and deposition of radioactive crud, and to facilitate decontamination. Additionally, these plants have proposed coolant chenistry control programs to reduce production and deposition of radioactive crud to minimize component failure. As a result of such design and chenistry control improvenents, these plants should not experience as pronounced a buildup of radioactive crud as older operating units, and the need for repair and/or replacenent of major components, such as BWR feedwater spargers and PWR steam generators, should be reduced.

With regard to operating plants, the staff is recommending a proposed rule, expected to be published within the next two months, that would require all plants to implenent an occupational ALARA-integrated radiation protection program. This rule is expected to result in licensees establishing internal review systens to evaluate and implenent occupational dose reduction techniques and component reliabil-ity improvenents. The staff has also published draft NUREG-0761, " Radiation Protection plans for Nuclear Power Reactor Licensees," which provided proposed NRR staff positions regarding ALARA.

We recognize that significant value can derive from more specific guidance to operating plants as to what chenistry control and materials improvenents might be reasonably implenented. To this end we are considering the fonnulation of a program to evaluate those design changes, such as replacanent of condenser tubes, and operating procedure improvenents, such as maintenance of proper pH, that have proven successful in reducing occupational dose and that can be reasonably impl enented. An initial step in this direction is being taken by the Office of Nuclear Regulatory Research to establish a contract to assist in the identification

• of these dose reducing plant improvenents. We expect this effort and a contractor report to be completed within a year.

Tr wry, % hva initiated actions to assure that plants currently under licensing review, including cFSSAR-80/Palo Verde, have incorporated plant equipment and operating programs including hign reliai,il;g equipment and radioactive crud reduction and renoval. For operating plants that inittaily did not include such consideration, we have in progress actions expected to result in each licensee

\

omcE )

SUNNAME) ,

DATE)

Noc renv aa m m Nacv co OFFICIAL RECORD COPY um _m m

P P. Shewnon establishing an internal review program to consider such improvanents, and actions to identify and promulgate specific improvenents to reduce workers' doses. We will keep you informed of our progress on these activities and welcome your comments and assistance as we proceed.

Sinc erely.

William J. Dircks -

Executive Director for Operations -

l DISTRIBUTION:

Central Reading File i NRR Reading File EDO Reading File RAB Reading File NRC PDR-w/ incoming LPDR-w/ incoming PPAS HRDenton EGCase l WJDircks KCornell PRehm VStello RMinogue CMichelson RCunningham DEisenhut SHanauer RVollmer PCheck BSnyder RJMattson RWHouston FJCongel CYChang

< VBenaroya DMCollins DMeyer ED0 l SCavanaugh-ED0#11863 r."<d" WJDircks l CPaul /P s'*f'#'ss "'/j 'f ,7v. /82 05/

SECY (3) [()fn C/ Y[s "M 4bo

/ _ ,

/Q,,g j o,,,m , DSig g c .

. 40%

FJCon e1

. EN9.:Mp[.p CYChMg jgCMEp.

OtM pya ,

Dsijpgg,7. ',4st,:gy,,'

JMattson

,,NaR HRDenton i sunswc ) DMCo1 },j,ns :km

, , , , , , , , , , , , , , , , , , , .hailsfon,,, , , , , , , , ,_ , , ,

05/ . ' . . ./82

,my 05/25/82 , , , ,05/g. .. /82 05/ $. ./.82

.. . . 0 5/. 2...f..../. 820 5../. 3 '(/. 8. 2... . 05/2g.../82 l snc resu m pan wcu om OFFICIAL RECORD COPY uscro. i9ei-aas w