Regulatory Guide 4.1

Measuring and Reporting of Radioactivity in the Environs of Nuclear Power Plants

ML13350A200
Person / Time
Issue date:	01/18/1973
From:	US Atomic Energy Commission (AEC)
To:
References
RG-4.001
Download: ML13350A200 (4)

1/18/73 U.S. ATOMIC ENERGY COMMISSION

REGULATORY GUIDE

DIRECTORATE OF REGULATORY STANDARDS

REGULATORY GUIDE 4.1 MEASURING AND REPORTING OF RADIOACTIVITY

IN THE ENVIRONS OF NUCLEAR POWER PLANTS

A. INTRODUCTION

(;Geneil Design

('C itein

4i .

'o.nitoring Radioactivitv Releases." ol' Appendix A it) 1( ('FR Part

50. "'(Lennd I Desigji ('iteria Ior Nun:leair Power Plants.'

requires that licensees provide for mroitioring the plant environs totr radioactivity that may lie released from normal oqperations. including anticipated operational occurrences, and fion pi!stulated accidents.

Subpala, ,rapih tall 2) of § 50.36a of 10 CFR Part 50

requires Ihat technical specifications for each license include a requirement that the licensee submit a report to the * ('tnniissiotn within 60 days after Janutarv I and July I of each year which. iii addition to specifying the quantity of each of the principal radionucides released to unrestricted areas in liquid and airborne effluents duting the last six months of operation,'

provides sitflicient intormation to estimate annual radiation doses W

to the public resulting from effluent releases.

Paragraph (c) of § 20.106 of 10 CFR Part 20 states that the CoInjIssion nMav limit the quantities of radioactive materials released in air or water duringi a specified period of time to assure that the daily intake of radia ctive materials from air. water. or food by a suitable sample of all exposed population group.

averaged over a time period not exceeding one year.

would not exceed specified quantities. Section 20.201 of

10 CFR Part 20 further requires that a licensee conduct surveys of levels of radiation or con1centrations of radioactive itaterial as necessary to show compliance with AIC regiulatioims.

"riis ginde describe.,

an acceptable basis for designing a progrant to measture and report levels of I At, :acct-t:M,-i"

pr,-grti is preseunt.l its saref v (.;tide 2 I (to)

he re sitsed :,%; : Regtla, try Gttide). "M ,:

avurini and I~ttep rling (fo Effluents frillr Ncttc'i:r llnwer Narls.'

radiation and radioactivity in the plamt environs. The provisions and principles in International (Commoissiotn on Radiological Protection (I('RI'l)

P ulicanion

7- pertaining to the releases of radioauctivitv during ornmal plant operation should be used as additional guidance in developing a program of this nature.

B. DISCUSSION

Present requirements to keep levels of radioactive material in effluents as low as practicable should assure that radiation doses to the puhlic resulinig front efflutent releases will continue to retnain mninimal. The type of program described in this guide is considered adequate to provide information needed to determine whether exposures in the environment are within prescribed or expected limits and to assure that long-term buildup of specific radionuclides in the environment will not become hazardous.

A preoperational program should be conducted in the environs of cach proposed nuclear power plant site to: (I) identify probable critical'

pathways io be monitored after the plant is in operation: (2) measore background levels and their variations along the anticipated critical pathways in the area surrounding the plant. (3) train personnel" and (4) evaluate procedures.

equipment, and techniques.

Years of experience at various Contitnissitt facilities have demonstrated that specific radionuclides behave in known ways under given environtmental cottditions.

Therefore. comprehensive and detailed envitonlmenial studies may not be needed at sires wiilh well known t C R P

ublication

"7. Iroin4 p!

t'"

h'id' ,'rt,o

'tlI

. Io,,itoring Related to thie' Il otdlhig of R idi., t'ti t

.1" 1,al riIt9.

Septemher 13. 196S t(henrenin rir It.'RI' I'Ltsicali ,tt I7.

t iF r the p ors've orf this. guite. thie Ierni "crilicar"t tit lit, same meaning as in t'RIt t'uhblication 7. Sipra niote 2.

USAEC REGULATORY GUIDES

ResfutAiorv Guide, Wi'. 1su"nf It' dtecrts amit flt~i't oAV.,Ihhtt In the p~ublic meiohorb.

Acc-titabl- lto the AEC stioclinoirs'taff of mtSiirmoni,roo %s~eci'c patrts of

'he Cnmm-n',s~

e.I55 to doiti-.1ie to-chnoriurs used hy the staff in

"aWAiiung S1 s*f14 W911f9.'tthi Of9 tnSIUtSi'd a~ccidenrim of Is isoisvde 9lwdaneem to With thf-fsitt A '995! Itjit.'ti Mi

'h-c A", soloot-9'5 dii etenl friom those set Dor o the gui~de, i to"I

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-1 tt't'v p'ovide i ti.1t9% 1(5 the finings d

flt9rlufsoi In ihm. issuane" ot cont~nUAA9CP' Of .. pe~m9o is' teens't, the

95'Cnmmosvo'

Putftshpcj i qud$S.lit ~t~s~ ~

,rti,

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coI9or.91.'

In iro-iwrnrcommodi.' ..

Copiei of oublishpil gui&ns m'sv be ObtainedI iv 10ourst .rsdic.lting ihe division%

desired io the US.

Atomice EitefqV

Commtttsi~to, VY-shIM9is..

D.C.

20Ob45.

Attention: Director of Regultfory Siend~itds. Cofnrmwnis Anil wrgoo'sions tot ir19ifovenerflts int these quidei are en'couraged And %thisuit he lenti t) ihes"

5'c~fiatv of the Commissuions.

US. Atomic EnetfgY Commisitn. W.Iihinaroin, D.C. 21if"45.

Aifent,nn: Chief. Public Peooceed-nos Sitaf.

The g,,.des ate issu~ed in itshe fotlhvittg tenr btirnd rss

1. Pow~er Reactor%

in'. P,oducis

2. Research And Test Reiclto.'

7. Itasnsttimti""

J. Fuels And Mate.'3s Fscdmtm'

B. orrciur.1iOn'si 9-J..111t

4. Environmintat and 5,5mm

'

Anf-l'usl RteW,~

5. Material% A"tS'ii Pitotwe'rs'etiof

10) 6--M~s S

bleu1vJirlon1etal nrsport process". Onc( e adequate sttudies have been done to assure that the tratisport processes are understood.

analyses otC

"indicator organiis'ns may adequately define radiotuclide levels in tile envirtomnent. The "'indicator orLalnis1t" concept of'

environmental samplinl"g involves tile practice o I

examining food chainls for selecied orga;nisins o0r materials which provide a sensitive and reliable mneatsure t' (lhe uti:Uatites of' eac'h (adiolluclide cycling throught each lood chaint. For example. ill the case where the plaitt'cow,'nilk-nian food chain is determined to be a critical palthway, it may not he necessar Ito extensively sample anld illeasure grazing plants :mnd f'odder to keep tliack of iodine-I 3l cycline in fhle food chain. sihce sampling and nieastiring tile milk produced by dairy cow\\s in stirrotndine areas may be :dequate.

At'ler the plant is iii operationt.

a program for me.*sturiniz radiation levels and radioactivity in the plant environs manst he maintained on :a cOnlintlilln basis to assist in verilt.,ing projected or ariicipated radioactivi 1v concentrations and related public exposures.

An entvironu ental tnonitoritng program shotld be flexible.

aid, as results are obtained. tihe prograni should be reviewed to identil'y any\\ necessary changes. The progra n shuhld then be appropriately nodified. The initial pttogram should be designed in accordance vith the followinug criteria:

I.

It should be based on the pathwayIs for the types radionuclides released froni stlrtoundine envi rotinten I

analysis of" critical and quanlities of the plant into the radioactivity in the environs may all be useful for this purpose.) Inifornation of' this nature will be of considerable help1 in inodil ying t[ie initial lnvilonllillental ti easure tut.nts program.

hil'orimalion obthaied f'ront this programn will le insed. in conjuintetion with data oil radioaclive effluents.

to evaluate mneasulres taken by 'ite licensee to assure that plantt releases to the environt1ient and radiation doses to the public are mailntinel wvitlhii the numerical dose limits determined by the Commission io be as low as practicable. Also. licensees' data will be compiled andi co III pared.

and a

comlrprehlensive stimitiray ii

1'

radioactivity in thle enivirons of nuttclkear power plants will be prepared by tlie Coimmission.

'[e Commission's Regulator.' siarf has evaluated the types of fitforination needed to provide supporting evidence for assessing tile pert'ormance of 'he plant witli respect to keeping populatnit exposures as low :is practicable and to verify predictions of concentrations ohI speciflic radiontiucl ides in lie environment based ott effluent iieasurements at the plan

t. Based on

1his evailtation and oil a review and assessment of' existline licensees' monitoring anid reporli g prograins. ihle s:tlt'

has developed tile regulatory position set forth belo'v.

C. REGULATORY POSITION

The proerani for nieasuring attd reporting clf radioactivity ill the environs ofi nuclear power plants must provide suitable inf'rs:auion from which levels of radiation and radioactivity in the environs of each plait carl be estimated. This inlfornation also may provide supporting evidence in evaluating tie perforniance of systems and equipment installed to control releases of'

radioactive material it) tile environnenw.

The basic principles set forth in this guide constitute an acceptable basis tor use in establishing an en viro ini ental Imonitoring program.

These sane principles will also b: used as bases in developing the licensee's corresponding technical specifications.

1.

Preoperational Program Potential critical pathways should he idemifiied prior to plant operation.

l';,e provisions in ICRV

FPtlblicaiion

7 rela ted to operational releases of radioactivity to the environm-nt should be used as a guide in determining critical radionuclides and pathways.

Other patlhways not directly related to humans should also be identified (see regulalory position 2.a. below).

Wherevet possible. suitable indicator organisms or media should be identified in each pathway.

2.

Operational Program a.

Sample Media Where practical. a suitable indicator organisin or ttedium in each critical pathway should be sampled

2.

It sihould consider tile possibility of buildup of long half-lived radiominclides in the environment and identify physical and biological sites of acctmniutlationt that ntaty contribute to huniani ex\\posures:

3.

It should be designed to facilitate use of reported levels of radiation and radioactivily in estimating annual radiation doses to tle public resulting froit effluents:

4.

It should consider the potential daimage to itttpot tant plants :mud arimals:'a i.

It should be designed to establish correlations between levels of radiation atid radioactivity in the environment and radioactive releases front plant Operation.

(A variety of lechniques. including measurements at control locations. preoperational surveys.

correlations with effluent data, and comparisons of operating versus shutdown levels of

'-A species. wthethe'r ainin

,tor plant is' "irnport:nlt'" (I) Kit is t'-nimeu

'rciatlv or r.creaLit ally vaitiau:tule. (2)

if it is rare ir e~ndanlge~red.

r

3) if ir t :iffect% thLe' ,vll-te.ing 'it stoF¢ importanI

sp¢i*c wiethin criteri: (I) and (2) ahiivc or (4) if it is critical to fit! structure and function (if (ht ¢crtiogical system. A "rare our endulangetred" species is any species cufficiatty tiesignated as such hb the 1).S. Hih and wildlife Service.

4.1.2

and analyzed for the critical iado mliclidels? released from the plant. An abundant, readily available form with nowt habits should be selected.

• Careftul attenttioni should ble given to avoid insdt(tLSng serious stress onl art ihm portan't species otf organism by a samipling program. Heavy sampling pressure added to natural prcdaliun and other elvironitSelillal stiesses could restil I

in tenpora ry obliteration of desirable potpulations. In stich cases.

other indigenotts hut al mnda n spcies souch as rodents.

rabbits or scrap lish. mayl be stilistituted as indicator org:antisms IthatI vill provide an estimate of the radionuclides avai.lable to main through natiral f'ood chains. In some instatnces. prop,!rly selected and sampled vegetam

11my 'list) provide a good imteaslie of the radionuclides in , critical FpatlIway.

WhcLtre use of a single indicator tneditim is impractical. samples of' several media from each pathway should be collected and analyzed. The C(ommission recomizes that some pathways do not have more than olne eiviromnittillal meditiht. c... external radialion exposures from clotds of uatnima-ray-emittitog radio- nclides inlvol-..

onlV onle paithway the atmosphere.

The actual tit:uhier of' media it he sampled in each pathwlay will be determined oni a case-by.case basis for each site. Itt some cases field measurements may be prelerable to collecting samples for laboratory analysis.

O

The program should include sampling of environmental media to estimate average radionuclide concentrations in important biota (see B.4. above).

Radiation exposures (external) and internal doses from short half-lived nuelides may be estimated by calculationrs

(,tisin g e[floeii mn easuremen ts and appropriate dispersion and concentration factors) rather

[han by routine collection of samples of environmental media. In some cases field measurements at certain locations to establish cotcert t rations of specific radionucl ides may be necessar". initially. to confirm predictionls.

h.

Sampling Frequency When a critical radionuclide has a short hallflife Imtinutes to days). it may be necessary to evaluate radiation expUsure by tuaking measurements in the field (e.g..

by use of thermoluminescen t dosimeters or portable multichannel gamma spectrometers).

When

I critical radionuclide with an internnediate half-life (weeks to months) is released continuotisly or frequently. sampling and analysis of etvirotlneinial media in the critical pathway should generally be carried omt at inltervals no greater than two or 'h ree half-lives of tIte iuclide. For long half[liife

.

dionuclides (years). measurements should be made at st once per year. Where seasonal eflects

,ay be important. sampling should be on a quarterly or at least semiannual basis.

Ilt sotmie cases. sat ll)lingll .1 t

• ll illttitous b:sis may be necessar\\ (e.g.. air samttplinig and co,]ItitIotIs mile astire ie Illt f. c u ttInlaIive exterit1al

,:dia, it in exposure). Composites of some selected s:aiple types.

such as air filters. niav be appropriate I'm" meastmrettiettt ot long-lived madi nit ticlides.

When critical pathlways become firmdly identified awtd correlations are developed between concentraiJuis of radionuclides itt einvirontm.entaml media anid planlt releases, or level, have been iotind too' low to detect. it is probable tltat saripling frequte .,cies ot'ccittil media irmay be apprli mriaiel " iticreased or decreased.

Such chan6ges shtIould onlyl he titade on itidividual paOwer plants after considerable

'peraliotlal experienlce Ilsa accrued.

c. Program Scope During (hft initial three years of commercial power operation (or other period corresponditie to maximum fuel burnup it] the initial core cycle). tihe mecastirememti program shotuld be relatively c11muipre- nensive in an attempt to verify anys' pr,*iected torle- lations between radioactivc eflltuilts attd levels in environtmental media. The extetnt of measturettent of environnmental media should be flexible and should depend on the type. quantity. and concentration of radionuclides from the plant as well as the results obtained from previotus nmeasurements.

1f. after this period. the licensee is able to demonstrate from levels in environutetumal media or calculations (using measured effluents and appropriate dispersion and bioaccumulation factors) that the doses from a particular pathway are sufficiently small, the number of media sampled in the patlihway and the frequency of sampling may be reduced. An adequate program wiln i

emphasis m

ml indicator o rganisins and selected media should still be continued in order to con firm that the levels of radioactivity in environmten tal media remain small.

d.

Analyses Samples should he analyzed for the critical radionticlide(s) released from the plani.

(Gross belta and gainnia analyses of samples stuch as air and fresh water may be useful to indicate that the concenltralioni of a critical radionuclide is not greater thall the delectioll capability for that nuclide.

3.

Detection Capabilities The detection capabilities associated with ,1,eaisiritmg and atinalvzitt radioactivity levels shotild he eSltablished primarily on the basis of poleittial hutnatt dose. The least detectable dose will vary from facilitvy to facility depending on the critical pathways ideI iifled arm d IItC

stalof-tl'-he-art of sampling and analysis in these pathways. Because of tie need for a preoperational monitoring program, detectiot capabilities for a

4.1-3

W

pat tcular piorat11 should he deternmined during :n early staLc of licensing. The staff rc,.ognizes that direct tmeeas uremtetn ts of envirotnml enltal Imredia cannot1 alvays

'cet ct levels lruepo

-dine to Commissiti design

, Iieclites. Nevertheless. every reasonable effort should be made to achieve detection capabilities which will dewclt ratdiition levels or radioactiVity I

ol0cent-rat ions ill critical pathways that could result in radiatiom doses cor respudindg to a 11ew 1'ercen t of thie Federal Radiation

(',tmcil's radiation protection guides Ie.g.. a ftw percent i!

!70 mren'years for whole body dose to a stiiable

-ample tithe exposed population ).

4.

Reporting of Results Data sholtld he reported to the Commission in the r..,ort suhmitted within t,-0 days aflter January I and July I of each year.'

InI the eveut that all unexpected mclea,ýe iln radjoaCtivMI

or r:diation levels is measured in a p-Mricular critical pathway. the Commnission should he not, fied prontptl..

Appropriate levels and reporting inetvals will he determined on an individual plant basis and included in the technical specifications for each license.

The Commission utilizes the data from these reports to provide assurance that man and his environment are not heinu subjc,:ted It unacceptable radiation exposures.

Consequently. all assumptions. parameters and methods used to measure and report radioactivity concentrations and radiation levels should be specified in the licensee's initial report aid updated in subsequent reports as s t-'d,.at Radiatiiin Councit Report No.

I.

bIac'kgroutnd

.llawrnelkr th'e" Dere'ml-Fea t ,.RadiathOn Pro'tetion Srandards.

Ia J3. 19 h (.

";uhpalragraph (a)(2)

of *50.3fia

(,f

1o C0 R Part 50

requites the subtinjsimi or a report within ot, d-'s after Jainuary I :ie-d Jul ' I i f eacit )'ear speciriflin the quantitv of eac lih o t .

prin`

iial radimiuclidts released lto unrestricted areas in liquid andll in g'awous erffenlt%.

the duta taken in suppnrt of the lite'i.ee'" en.-iroiitnential monitoring programn shriuld also he

,,jonmia ltd s;emiannually. Ir additional lime is needed, the repnrt stler*th .sit;

indicane :md the d*t:n shoulJ he carried o*er into the Io'et

,emiannua:ll report. it would greatl, r:ocililgte comparismns rnd

7.'ierrlaitil ot t ta if the en sir.*inieint

3ind effluent niaiateirilg dat.a m.ere .mnihtited ilnto single reports.

alpprolri:e. Trie licensee should demtostiale that aill assutittiolts. parameters and methods, used are adcqumtte and compiele Ito allow Itwhere data pertii) a c omparison

,

with predicted concei.ratitms and doses based ol effluents from each nuclear power plant under license.

(See Safety (uide 21).

To petlmit comparison of signi'icart entvironmental mIolnitoritng data willh predicted eoncent ratiotls anid doses (bhaid on reluiretletts ol' I0 CFR Part 50). the report should include Ilie following i tents for each enviro*mttlenttal tttedii: :1:

a.

Samnple Type I.

Biological (it tile extent practicable. list specics.

life' stage.

age.

weight or size.

biolog.ical conditiot, tissue or m1terial sampled. sample weight.

etc.).

2.

Non-Biological (identify type - soil, air.

etc.: list actual area.

depth and weight or volume sampled as appropriate, whether grab or continuous sample. number of samples. etc.).

b.

Sample Localtion (also !tipply mtap showing locations)

c.

Collection Period (continuous samples) or Dale of Collection d.

Critical Pathway e.

Radionuclide f.

Concentration (mCi/ml or g. specifying wet or standard dry. weight) and/or Deposilion (jiCi/mh ori other apprupriate units of tteastire). (List conversionti, factors relating sample activity and volume - depth X

cross section - It) total area deposition: average and ttlaXIillttt values (for each medium. etc.)

g.

Background Value h.

Analytical Method 7 j.

Comparison of Observed Concentrations.

Depositions and Estimated Doses with Predicted Values (based on effluent measurenments)

j.

Remarks (be sure to explain any tititstal measurements or deviations).

'I .stim-mtes i)f the error assoeinted with the: measurement of each environmental medium should he reported.

O0

4.1.4