43906 Federal Regtster f Vol. 49, No. 212 I Wednesday, October 31, 1984 I Proposed Rules ·==-

ENVIRONMENTAL PROTECTION 

AGENCY 

40 CFR Part 61 

[AD-FRL 2694-2] 

t~~tlonal Emission Standards for 

Hazardous Air Pollutants; Regulation 

of Radlonuclldes 

AGENCY: Environmental Protection 

Agency (EPA). 

ACTION: Withdrawal of proposed standards. 

SUMMARY: On April6, 1983, the 

Environmental Protection Agency, pursuant to section 112 of the Clean A1r 

Act, proposed standards for sources of 

em1ss1ons of radionuclides m four 

categories: (1) Elemental phosphorus plants; (2) Department of Energy (DOE) facilities; (3) Nuclear Regulatory CommiSSIOn (NRC)-licensed facilities 

and non-DOE Federal facilities: and (4) underground uramum mmes. In addition. 

the Agency dec1ded not to propose standards for the followmg source 

categones of radionuclide emissions: (1) Coal-fll'ed boilers; (2) the phosphate mdustry; (3) other extraction mdustnes; (4) uramum fuel cycle facilities, uraruum 

mill tailings, and management of high- level radioactive waste; and (5) low 

energy accelerators. The Agency IS 

announcmg the withdrawal of its four 

proposed standards for radionuclide 

em1ss1ons under Section 112 of the Clear 

A1r Act and affirms its ongmal deCISion 

not to regulate emtsstons from the other 

five source categones constdered. The 

U.S. Distnct Court for the Northern 

Distr1ct of California has ordered EPA to 

take final action on its proposed standards by October 23, 1984. 

DATE: Th1s withdrawal Is effective 

October 31, 1984. 

ADDRESS: The rulemakmg record IS 

contamed m Docket No. A-79-11. Tlus 

docket IS available for public mspection between 8:00 a.m. and 4:00 p.ID., Monday through Fr1day, at EPA's Central Docket 

Section, West Tower Lobby, Gallery One, Waters1de Mall,401 M Street, SW., Washington, D.C. 20460. A reasonable 

fee may be charged for copymg. 

FOR FURTHER INFORMATION COHTAC'r. 

James M. Hardin, Environmental 

Standards Branch (ANR-460), Critena 

and Standards DiVlSlOD, Office of 

Radiation Programs, U.S. EnVIrOnmental 

Protection Agency, Washmgton, D.C. 

20460, (703)557-8977 

SUPPLEMENTARY INFORMATIOtl: 

I. Supporting Documents 

A final Background Information 

Document has been prepared and smgle 

cop1es may be obtamed by writing the 

Program Management Office, Office of 

Radiation Programs (ANR-458), U.S. 

Envll'orunental Protectton Agency, Washmgton, D.C. 20460, or by calling 

(703) 557-9351. Please refer to 

"NESHAPS-Radionuclides: Background Information Document for Final Rules, Volumes 1 and 2 [EPA 520/1-84-022-1, EPA 520/1-84-022-2], Qctober 1984. 

These documents compnse the 

mtegrated nsk assessment performed to 

prov1de the scientific bas1s for tlus 

rulemaking. Volume 1 of the Background Informatibn Document contams a complete descnption of the Agency's methodology used m its nsk assessment 

of the hazards assoc1ated with mbome 

emissions of radionuclides. Volume 2 IS 

devoted to a detailed descnption of how 

the Agency applied this methodology to 

each source category considered m tlus 

rulemakmg. For each source category, tlus document describes the 

radionuclide em1ss1ons, estimated doses 

and r1sks to nearby mdividuals and to 

populations, description of current 

enuss1on control technology, and 

descnptions and cost estimates of 

additional emiSSIOn control technology. The Agency's written responses to 

oral and written comments_ on the 

proposed standards have been placed m 

Docket No. A-79-11. Single cop1es of the 

Agency's responses may be obtamed by writing the Program Management Office, Office of Radiation Programs (ANR458), U.S. EnVU'Onmental Protection 

Agency, Washmgton, D.C. 20460, or by calling (703) 557-9351. Please refer to 

"NESHAPS-Radionuclides: Response to 

Comments for Final Rules, Volumes 1 

and 2" [EPA 520/1-84-023-1, EPA 520/ 

1-84-023-2), October 1984. 

n. History of Standards Development 

In 1977, Congress amended the Clean 

All' Act (the Act) to adddress a1rborne 

enusstons of radioactive matenals. 

Before 1977, these em1sstons were either 

unregulated or were regulated under the 

Atonuc Energy Act. Section 122 of the 

Act reqwed the AdmiDlstrator of EPA. 

after provtding public notice and 

opportunity for public hearmgs (44 FR 

21704, April u. 1979), to deternune 

whether emiSSions of radioactive 

pollutants "cause, or contribute to, a1r 

pollution winch may reasonably be 

anticipated to endanger public health." 

On December 27, 1979, EPA published a 

notice m the Federal RegiSter listing radionuclides as a hazardous wr 

pollutant under section 112 of the Act 

(44 FR 76738). Th1s.action was based on 

the Agency's finding that studies of the 

b1olog1cal effects of 1omzmg radiation 

mdicated that exposure to radionuclides 

mcreases the nsk of human cancer and 

genetic damage. In addition, the Agoncy found that emissions data mdicated that 

radionuclides ore released mto a1r from 

many different sources with tho rosult 

that millions of people are exposed. To 

support these findings, EPA Issued n 

report entitled "Radiological Impact Caused By EmiSSions oof Radionuclldcs 

mto Atr m the United States, 

Prelimmary Report," [EPA 52017-79-

006), Office of Radiation Programs, U.S. 

EPA, Washmgton, D.C., August 1970. 

Section 122(c)(2) of the Act directed 

that, after havmglisted radionuclidos us 

a hazardous a1r pollutant, EPA enter 

mto an mteragency agreement with tho 

Nuclear Regulatory Commlss10n with 

respect to those facilities under NRC 

Jurisdiction. Such a memorandum of 

understanding was effected on October 

24, 1980, and was subsequently published m the Federal Register (45 FR 

72980, November 3, 1980). When EPA 

began developmg standards for 

Department of Energy facilities, a 

sliDilar memorandum of understanding 

was negotiated with DOE and signed m October 1982. Cop1es of both those 

memoranda have been placed In tho 

Docket for public rev1ew. 

On April&, 1983, EPA announced Ito 

proposed standards for sources of 

enuss1ons of radionuclides from four 

categones: (1) Elemental phosphorus plants: (2) DOE facilities: (3) NRclicensed facilities and non-DOE Fodorol 

facilities: and (4) underground uranium 

mmes. Several additional source 

categones emitting radlonucUdes woro 

tdentified m the notice. However, the 

Agency concluded that good reasons 

eXIsted to propose not to regulate the so 

categorxes, wh1ch mcluded: (1) Coalfired boilers; (2) the phosphate industry; 

(3) other extraction mdustms: (4) 

uramum fuel cycle facilities, uranium 

mill tailings, and management of h1gh· level radioactive waste; and (5) low 

energy accelerators (48 FR 15076, Aprll 

6, 1983). At the time of proposal, it was 

thought that these nme source 

categones were all that potentially released radionuclides to a1r at levels 

that could warrant regulatory a ttention. In support of these proposed standards 

and determmations, EPA published a 

draft report entitled "Background Information Document, Proposed Standards for Radionuclides," [EPA 520/ 

1-83-001), Office of Radiation Programs. U.S. EPA. Washington, D.C., March 1983. 

Followmg publication of the proposed standards, EPA conducted an informal 

public hearmg m Washmgton, D.C., on 

April 28 and 29, 1983. The comment 

penod was held open an additional 30 

days to receive written comments. 

Subsequently, EPA rece1ved a number of 
Federal RegiSter I Vol. 49, No. 212 I Wednesday, October 31, 1984 I Proposed Rules 43907 

requests to extend the time for 

subiruSston of public comments and to 

conduct a public heanng outside of 

Washmgton, D.C., .on the proposed 

standards to accommodate those were 

unable to attend the first heanng. In 

response to these requests, EPA 

extended the comment penod by an 

additional45 days-and held another 

mformal public heanng m Denver, 

Colorado, on June 14, 1983 (48 FR 23665, 

May 26, 1983). 

merits or the critiCISmS ond SU£~estions 

presented by the Subcommittee. This 

request was derued. 

On August 24, 1984, EPA announced 

m the Federal Register the ovoUabiJity 

of new techrucal mformntion (49 FR 

33695). The public was encourn:;ed to 

comment on thJs new mformation wh1ch 

mcluded the F'mal Report of the SAB 

Subcommittee, transcnpts of all public 

meetings of the Subcommittee, 

mformation presented to the 

Subcommittee, and technical 

mformation relevant to elemental 

phosphorus plants and underground 

uraruum mmes. Tlus new mfonnaUon 

was available m the Docket on 

September 7, 1984. The Agency's 

responses to these comments nrc 

mcluded m Volume 2 of "NESHAPSRadionuclides: Response to Comments 

for Final Rules." 

m. Summary of the F'mnl Actions. 

On April6, 1983, the Agency proposed 

standards for sources of elDISSions of 

radionuclides m four categones: (1) 

EPA has considered and responded to 

all written and oral comments: a copy of 

the Agency's responses IS m the Dockel 

The Background Information Document 

has been revtsed and published m final 

form. In addition, a final econolDlc 

analysis of the unpact of the proposed 

standards for elemental phosphorus 

plants has been completed and placed m 

the Docket (Refer to "Regulatory Impact 

AnalysiS of Eiruss1on Standards lor 

Elemental Phosphorus Plants," October 

1984) •. The final report on control 

technology for radionuclide eiruSsions to 

rur at Department of Energy facilities 

has been published and a copy 18 

available mt he Docket (Refer to 

"Control Technology for Radioactive 

Enuss10ns to the Atmosphere at U.S. 

Department of Energy Facilities," [PNL4621], October 1984). 

In response to requests for Wider 

sCientific revtew of the Agency's nsk 

assessment, the AdlDlmstrator m 

December 1983, formed a Subcommittee 

on Risk Assessment for Radionuclides 

withm the Agency's SCience Advtsory 

Board (SAB) to reVIew the sCientific 

basiS for the proposed standards. TbJ.s 

revtew JS disCllSsed m more detail m 

Section IV of this notice. On the basis of 

the Subcommittee's reVIew, the final 

Background Information Document has 

been rewritten to mcorporate 

recommendations made by the 

Subcommittee. The reVISed Background 

Information DoCllment presents an 

mtegrated nsk assessment followmg the 

format and methodology suggested by 

the Subcommittee. to the extent 

possible. 

• Elemental phosphorus plants: (2) DOE 

facilities: (3} NRC-licensed facillties and 

non-DOE Federal facilities: nnd (4) 

underground uraruum mmes. For DOE 

facilitie.s, the Agency proposed on 

emission limit not to exceed an amount 

that causes a dose eqwvnlent rote of10 

mrem/y to the whole body and 30 

mrem/y to any organ of any mdiv1dual 

livmg nearby. For NRC-licensees and 

non-DOE Federal facilities, the Agency 

proposed an elDISSion limit not to 

exceed an amount that causes a dose 

eqwvalent rate of 10 mremly to any 

organ of any member of the public. The 

emJSsion limit proposed for elemental 

phosphorus plants was 1 Cl/y of 

poloruum-210. 

On February 17, 1984, the Sierra Club 

filed suit to compel final action m the 

U.S Distnct Court for the Northem 

Distnct of Califorrua, pursuant to the 

citizens' suit proVISion of the Act (Sierra 

Club v. Ruckelshaus, No. 84-0656 

WHO). In August 1984, the Court 

granted the Sierra Club's summary 

Judgment motion and ordered EPA to 

take final action on its proposed 

standards by October.23, 1984. On 

September 14, 1984, the AdlDlmstrator 

requested that the Court delay its 

deadline until fanuary 1985 to hun 

enable hun to personally evaluate the 

For all three of these source 

categones, the Admlwstrntor has 

deterlDIDed that current practice 

proVIdes an ample margm of safety m 

protecting the public health from the 

hazards associated with exposure to 

Slrbome radionuclidcs, and has 

therefore deCided to withdraw the 

proposed standards. 

In the case of underground uraruum 

mmes, the Agency proposed a standard 

to limit the annual average radon-222 

concentration m a1r due to emissions 

from an underground mmc to 0.2 pCi/1 

above background m any unrestricted 

area. The Agency IS also withdrawmg 

thJs proposed standard bencause It has 

concluded, for the reasons discussed 

below, that it did not meet the legal 

reqwrements of Section 112. The Agency 

has received additional technlcal 

mformation that suggests the possibility 

of usmg bulkheadin.!; and other 

techniques to control radon emissions. 

However, pursumg thJs course of action 

\'JOS not od\'ocnted or even su~ested m 

the propos:1l. Indeed. the mformation 

available to EPA at the time of proposal 

mdico.ted that these techwques were 

costly and "not very effective•• and the 

A:;:ency dismissed these tech.wques as 

the basiS for an elDISSion standard {48 

FR 15083, col. 3). Since that time. new 

mformation suggests that conclusion 

may be erroneous. Tech.wcal 

mformation on wluch the base or final 

regulation or a proposal1s not yet 

available: further work 1S needed to 

demonstrate ho\'1 to set such a 

regulation at some future time. 

Therefore, the Ascncy 1s publishmg. 

samult:meously with this notice, an 

Advance Notice of Proposed 

Rulemakms for Radon-222 Eiruss1ons 

from Underground Uraruum :Mines to 

solicit additional mformation on control 

methods, such as bulkheading and other 

forms or operational controls. for radon222 enuss1ons from these mmes. Such an 

approach could avoid many of the 

techrucal and legal difficulties pose by 

EPA's proposed standards. 

In addition to the four source 

categones for wluch EPA did propose 

standards, the Agency has made a final 

deterlDIDalion nol to regulate the 

followmg five source categones: (1} 

Coal-fired boilers: {2) the phosphate 

mdustry: (3) other e.xtraction facilities; 

(4) uraruum fuel cycle facilities:uramum 

mill tailings. and management of }ughlevel radioactive waste; and (5} low 

energy accelerators. The Agency did not 

receive any new mformation dnnng the 

public comment penod that convmced it 

of a need for regulation of any of these 

five cntegones. Therefore. the 

AdlDlrustrator affirms the ongmal 

deciSIOn not to regulate these sources, 

belieV1Dg that adequate public health 

protection ex~sts to satisfy the 

reqtlll'ements of the Clean A1r Act. 

When the Agency promulgated its 

standards for activC'uramum mill 

tailings (40 CFR 192. Subparts D and E), 

it deeded that the control of the radon222 elDISSions from the active uramum 

mill tailings piles could more 

appropnately be considered under the 

Clean A1r Act, rather than the Uramum 

Mill Tailings Radiation Control Act. The 

preamble to the final uramum mill 

tailinss standards noted that work 

practice standards were probably the 

most practical way lo control radon 

enuss1ons at active uraruum mills. 

Consequently, EPA 1s 1ssumg. 

Simultaneously with this notice, an 

Advance Notice of Proposed 

Rulemaklllg for Radon-222 EmlsSions 

from Ltcensed Uramum Mills. 
, 

43908 Federal Reg1ster I Vol. 49, No. 212 I Wednesday, October 31, 1984 / ·Proposed Rules 

The withdrawal of the proposed standards for elemental phosphorus plants, Department of Energy facilities, 

Nuclear Regulatory Comrrusston- licensed facilities and non-DOE Federal 

facilities, and underground uraruum 

mmes are final actions. Also, the 

dectston not to establish radionuclide 

emtsston standards for coal-fired 

boilers: the phosphate mdustry, other 

extraction mdustnes: uraruum fuel cycle facilities, uraruum mill tailings, and 

management of high-level radioactive 

waste: and low energy accelerators are fmal actions. Judie~al revtew 1s available 

only by flling a petition for rev1ew m the 

United States Court of Appeals for the 

Distnct of Columb1a Circuit wiUun 60 

days of today's publication datA. 

ill. MaJOr Issues R81Sed m Public 

Comments 

Many commenters expressed considerable dissatisfaction with the 

proposed standards. Operators of 

facilities .for which standards were proposed obJected VIgorously to the 

stnngency of the proposed standards; 

other groups obJected on the grounds 

that the proposed actions were not 

suffiCiently protective ofpublic health. 

Both groups-criticiZed the proposed standards for not meeting the mtent of 

the Clean Alr Act. 

A number of comments were made 

which apply to all of the source 

categones constdered and which 

address the bases of the standardssetting proce.ss. The followmg 1s a summary of the most stgnificant 

comments and the Agency's responses: Comment· Radionuclides should not 

be constdered a hazd.rdous atr pollutant under section 112 of the Clean Alr Act 

because ambtent levels do not pose a sJgnificant nsk to human health. One 

commenter petitioned for 

reconsideration of EPA's listing of 

radionuclldes as a section 112 pollutant, on the basts that the Agency had not 

JUStified its concluston that 

radionuclides are hazardous atr 

pollutants withm the mearung of section 

112. 

Responses: EPA has concluded that 

extsting radionuclide enusstons .from 

some stationary sources can represent a 

significant nsk of fatal and nonfatal 

cancers to exposed populations. There lS 

no sc1entific doubt that radionuclides are carcmogens. Tlus conclus1on ts 

based on extens1ve SCientific eVIdence 

denved from studies of populations of 

humans and ammals exposed to 

radiation at vanouslevel& rangmg from 

very high doses to doses only slightly greater than envtronmentallevels. 

Both tlus concluston and EPA's 

specific nsk esitmates are based on the 

wxdely used assumption that there 19 no threshold below which exposure to 

radiation does not pose some nsk to 

human health. Based on thts prelnise, EPA concludes that exposure to 

radionuclides at low levels m the 

ambtent atr presents a nsk of fatal and 

nonfatal cancers, as well as genetic damage. 

In addition, section 112 reqmres not 

only a finding that the pollutant at tssue 

1s hazardous m the abstract, but also 

that it poses a public health nsk m its 

form as an atr pollutant. EPA has 

evaluated the atr pollution nsk of 

radionuclide einlsstons based on the 

magnitude of such enusSlons from 

stationa..."'Y sources to the ambtent atr, on observed and estimated ambtent 

concentrations of radionuclides, on the 

proxmrity of large populations to , emitting sources, on estimates of health 

nsks to exposed populations, and on considerations of uncertamties 

assoCiated with rtsk estimates. Based on this analysts, EPA has 

concluded that the present record does 

not support regulation of any of the 

source categones for whlch regulation 

was proposed. Tlus concluston, 

however, does not support de listing of 

radionuclides, because, m the case of 

uramum mmes, the nsks appear 

suffictent to warrant future regulatory action under section 112. It ts only • because regulation of the appropnate 

type ts tmpossible at this time, due to 

the need for further work on the 

techrucal1ssues and the need to proVIde an opporhmity for notice and comment on any proposed action, that no rules for 

uraruum_mmes are bemg mcluded m tlus 

deCISIOn. 1 

Therefore, with respect to the petition for reconsideration of the listing of 

radionuclides as a hazardous atr 

pollutant, EPA has constdered this 

option and has rejected it. believmg that 

the ongmal deciSlon to list under section 

112 1s still appropnate. Commellt: The EPA standards are unnecessary because current 

adm.unstrative or regulatory standards 

of 500 mrem/y to the whole body and 

1500 mrem/y to any organ (Federal 

Radiation Council gwdance and NRC 

regulatory values), coupled with 

directives to keep enuss10ns as low as 

'The AdmJru5trator believes, based on an analy$t8 by EPA'1 Office of General Counsel, that 

today'• action• are conatatent with the statute and 

the court ordC!l' govenung today' a dec18lon. EPA 

acknowledges, however, that IU11L1811Dlent ex! ala 

that the only proper way to procedurally expre31 

the 1ubstantive concluatons set forth In today' a rulemalang Ia by della ling the particular pollutant mv.olved. Thouah EPA does not preaently accept that poalijon,lt atand1 ready to amend thta package promptly alonslheae lines if the Court should so 

dlrecL 

practicable, are adequately protective of 

the public health. Other commentors felt 

that the proposed standards wore too 

lax and that the Agency should set an 

enuss1on limit of zero, with exceptions allowed only after a case-by-case exammation. 

Response: EPA doeQ not believe that 

current Federal Radiation Council 

gwdance and NRC policy of limltlng 

exposure to mdiv1dunJs to 500 mrem/y 

to the whole body and 1500 mrem/y to 

any organ protects public health with an ample margm of safety, as requued by the Clean Alr Act. EPA estimates that 11 

person recetvmg 500 mrem/y to the 

whole body over a lifetime would have an added potential nsk of devaloplng a fatal cancer of about one In one hundred 

due to the radiation exposure. In 

addition, that same person would face an approXllllately equallovel of risk of 

nonfatal cancer and of passing on . nonfatal genetic ,effects to succeeding generations. 

However, EPA recognizes that tho "as 

low as reasonably achtevable" 

(ALARA) emtsstons policy had led to 

generally low einlsstons of radionuclldes 

from most facilities. The Agency oxpoots that tlus current policy will continuo In 

the future and docs not anticipate an mcrease m the emtssion level or the 

assocmted rtsks. Therefore, tho Agency 

believes that in cases m which 11 

VIgorous and well-1mplemcnted ALARA 

program has achieved low emissions, 

such practice can provide o.n ample 

margm of safety for public health 

protection. 

The Agency does not agrea with lho 

approach of establishing an emission 

limit of zero. The tmplementatlon of 

such a standard for the sourca categones constdered would be 

extremely burdensome, and would 

result m little tmprovement m public health. More tmportant, however, is tho 

Adnurustrator's determmotlon that 

public health 1s currently protected to a 

degree whtch satisfies the requirement of Section 112 of the Act. 

Comment: EPA ts required to 

promulgate standards under all of lts 

applicable authorities m order to {ultill 

the mtent of ita Congresstonal mandates. For example, the Agency 

must regulate atr emtsstons from uraruum fuel cycle facilities under the 

Clean Alr Act, as well as under the 

Atonuc Energy Act. 

Response: The Agency believes thut 

its pnmary objective Is to provide reasonable public·health protection, but 

that it was not the mtent of Congress tltat the Agency 1ssue dtJpllcatlve regulations to achteve thts goal. In light 

o£ the limited resources In both lha 
Federal RegtSter I Vol 49, No. 212 / Wednesday, October 31, 1984 I Proposed Rules 43909 

public and pnvate sector, it would be 

mefficient and mmecessarily 

complicated to reqwre sources to 

comply with a standard they already 

meet. or alternatively, to meet several 

comparable standards set by one 

Agency under different statutory 

authorities. 

Comment: Some commenters stated 

·that the standards should be based on 

cost analyses, and if not cost-effective, 

they should not be promulated. Others 

felt that costs should not be considered 

at alL 

Response: The Agency believes that 

g1vmg equal wetght to costs and benefits 

IS mappropnate m developmg standards 

under Section 112 of the Clean Alr Act. 

Congress clearly mtended that public 

health protection considerations be 

pnmary and that cost be secondary. 

The Agency did consider, m 

developmg these rules, the availability 

and practicality of control eqwpment. 

While thts was not a pmnary 

constderation, knowledge of the 

availability of control technology lS 

necessary when makmg Judgments on 

the need for and level of eiiDssion 

standards. EPA believes these 

considerations are withm the 

Adm.uustrator's discretion m 

deteriiDnmg what level of protection 1s 

adequate. The Agency constdered costs 

to a limited degree consistent with tins 

overall perspective m reachmg its 

dectstons on coal-fired boilers and 

elemental phosphorus plants, but 

otherwise today's action does not rest 

on cost considerations. 

Comment: Some co~ters stated 

that the Clean Alr Act reqwres 

standards for all source categones releasmg Significant amounts of 

radionuclides mto the 811'. 

Determmations that standards are not 

needed are not allowed for any reason. 

Others supported EPA's deteriiDnations 

that standards for some categones are 

unnecessary. 

Response: The comment that every 

stack emitting radionuclides to aU' must 

be subJect to an eiiDsston limit 

established under the Clean Alr Act 

must be considered m light of the' fact 

that every stack m the United States 

discharges at least mmute quantities of 

radionuclides. These radionuclides 

mclude certam kmds of carbon and 

potassium atoms and other naturallyOCCUI1'1D8 radionuclides. Because these 

eiiDSStons are so small, the nsk to 

nearby mdiVIduals and the total 

population group Is Immmal. To regulate 

these sources would not significantly 

rmprove the public health. 

Section 112 of the Act reqwres the 

Adnurustrator to assure public health 

protection with an ample ma.JgJJl of 

safety. A negative detemunation of the 

need for standards IS penmssible ,.,ithm 

the context of the Act. so Ions as thw 

critenon ts met. With respect to eight of 

the source categones constdered m tlus 

rulemakmg, the Agency has concluded 

that the public health ts adequately 

protected under current practice, and 

therefore has met the reqwremenro of 

the Act. For the uramum mmes category. 

the Agency concludes that nsl:s are 

stgnificant; however, there 1s presently 

no feasible way to establish an eiiDsston 

standard. The Agency will cons&der such 

a standard, together with alten13tive 

destgn, eqwpment. wor!• practice and 

operational standards, for future 

proposal. 

Comment: There has not been 

suffiCient reVIew outstde the Ag<:ncy of 

EPA's methods and procedures for nsk 

assessment. Specifically, EPA's Sctence 

AdVIsory Board should reVIew the 

sctentific basts of the proposed 

standards for radionuclides. 

Response: The Agency agrees with 

tins comment {see section V below). 

Comment: The proposed standards 

should not be promulgated because they 

cannot be Implemented with reasonable 

procedures. Compliance with mdircct 

eiiDsston standards {dose or 

concentration limits at site boundary) 

must be determmed by enwonmental 

measurements at the site boundary. 

Because the proposed standards are so 

restrictive, thls IS either very e"-penst\'e 

or altogether Impractical. 

Response: Questions concernmg the 

Implementations of standards for 

a1rbome radionucllde ermsstons are 

moot m light of the Admmtstrotor's 

dectston to withdraw the proposed rules. 

Comment: Standards should be 

conststent with established 

mtemational and national poliCies and 

regulations goveilWIS radiation 

protection. as well as among each 

source category. Response: The Agency agrees with 

thts comment and has based its decsston 

to withdraw the proposed standards, m 

part, on the fact that current practices m 

radiation protection do proVIde 

adequate public health protection. 

Comment: Standards should allow for 

greater operational flexibility tn 

selecting control technology. 

Response: Questions concenung the 

amount of operational flexibility 

necessary to comply with standards for 

atrbome radionuclide emtsmons are 

moot m light of the AdmiDlStrator's 

deCISion to withdraw the proposed rules. 

V Techmcal Rev1ew by the SClonco 

Ad\oisory Board 

In response to critiCism that the 

Agency did not have suffictent outstde 

re\'Jew of its methods used to assess nsk 

due to radionuclides. the Adm.mistrator 

formed a subcommittee of the Agency's 

SCience Ad\'lsory Board to reVIew the 

sctentific basts of the proposed 

standards for radionuclides. The 

Subcommittee held three public 

meeUn:;s: the tll'St on January 16. 1984, 

the second on February 21-22.1984, and 

the tinrd on March 22. 19i34. At these 

meetings, the Subcommittee was briefed 

by Agency staff on the methods used m 

estimating nsks caused by aJl'bome 

radionuclides. The panel heard from 

members of the public on the Agency's 

nsk assessments, as well. The 

Suocommittee also held executive 

sess1ons to constder the mformation 

presented by the Agency and the public. 

Transcnpts of the public meetings are 

a\•ailable m the Docket. The 

Subcommittee's final report, entitled 

"Report on the Saentific BaSIS of EPA's 

Proposed National EmlsS!on Standards 

for Hazardous Alr Pollutants for 

Radionuclides," was transmitted to the 

Admunstrator on August 17, 1984. A 

copy of tins report and the Agency's 

response are available m the Doc.la!t. 

In the E.xecutive S1liD.IIllUY of its 

report, the Subcommittee noted that its 

activities could be \'lewed as addressing 

two mterrelated questions. First. did the 

Agency's staff collect the SCientifically 

relevnnt data and~ SCientifically 

defensible approaches m modelin~ the 

transport of rodionuclides through the 

enVll'onment from 8ll'bome releases, m 

calcul:1Un:; the doses reCC1ved by 

persons mhalins or mgesting tlus 

radioactivity and m estimating the 

potential cancer and genetic nsks of the 

calculated doses? Second. are the 

mdiVldual facts, calculational 

operations, SCientific Judgments. and 

estimates ofuncertamty documented 

and mtegrated m a clear and logtcal 

manner to pro1l1de a risk assessment 

that can be used as a sCientific basiS for 

nsk management purposes, i.e .. 

standard·setting? With regard to the first 

question. the Subcommittee concluded 

that EPA had gathered the appropnate 

sctentific mformation needed for a nsk 

assessment m a techmcally proficient 

manner. 

The Subcommittee made several 

technical su:;geslions on how EPA could 

Improve its as5llmptions, models, and 

methods for estimating nsks. Most of 

these techrucal suggestions have been 

mcorporated tnto EPA's nsk assessment 

procedures. The nsk assessmeJlt for the 

final rule reflects these modifications. 

Some of these techrucal suggestions 

mvolve additonal research to tmptove 

future nsk assessment methods. Those 
43910 Federal Reg~.ster I Vol. 49, No. 212 I Wednesday, October 31, 1984 I Proposed Rules 

suggestions will be used as EPA 

conducts new studies. 

The Subcommittee's greatest criticism 

m its report was related to the second 

question. They concluded that EPA had 

not assembled and mtegrated the 

available sc1entific data m the format of 

a r1sk assessment that provtdes an 

adequate bas1s for regulatory deciSions. 

The panel suggested the need for an 

mtermediate step between the collection 

of the relevant tecluucal mformation 

and the selection of regulatory options. Specifically, they encouraged the 

Agency to assemble an mtergrated nsk 

assessment document that would lead a 

dec1s10nmaker step-by-step from the 

identification of em~ss1on sources, 

through the calculation of radiation 

doses and the assoCiated degree of 

uncertamty, to a vanety of regulatory options from which to choose. Only m 

th1s way did the Subcommittee feel that 

a policymaker could be presented with 

all the facts necessary to make a 

responsible regulatory deCision. Further, 

th1s analysis would enable the sc1entific 

community and the public to understand 

the rationale and bas1s for the Agency's actions. 

The Agency recogruzes and 1s 

concerned about the adverse criticism of 

Its processes by its own Sc1ence 

Advisory Board. EPA does believe that. 

on balance, its nsk estimates for specific 

sources of radionuclide eJlllSSIOnS are 

accurate withm the limitations mherent 

m makmg such estimates. It 

acknowledges, however, that the 

critic1sm of the Board does cloud the 

rulemakmg record, and that the 

Subcommittee's concerns, by thel.I' very 

nature, cannot be fully addressed with1n 

the time available for this declSlon. 

Nevertheless, the final Background Information Document has been greatly modified to encompass the format and 

suggestions of the Subcommittee to the 

extent possible. However, the 

Subcommittee has not reviewed tlus 

revtsed document. 

The Sc1ence AdviSory Board also 

made several procedural suggestions for 

1mprovmg the Agency's nsk assessment 

methods. These recommedations will be 

mcorporated mto the Agency's 

procedures and processes. Detailed 

responses to the Sc1ence Adv1sory Board's recommendations can be found 

m Volume 2 of "NESHAPSRadionuclides: Response to Comments 

for Fiscal Rule.'' 

VL Perspectives on Risk Assessment 

Today's deciSion 1s based on a 

developmg body of sc1ence and policy 

concemmg the treatment of one 

particular class of hazardous 

substances, namely matenals that 

cause, or are thought to cause, cancer. In 

some cases, SCientific eVIdence mdicates 

that a g~ven substance 1s hazardous at 

lugh levels or exposure, but has no 

effect below a certam level. For most 

carcmogeruc substances, however, 

SCientists are unable to tdentify such a 

threshold below wluch no effects occur; 

moreover, to the extent sctentists 

understand the process of 

carcmogenesiS, there IS some reason to 

believe such thresholds may not eXIst. For these kmds of substances, EPA and 

other Federal agenc1es have taken the 

position that any level of exposure may 

pose some nsks of adverse effects, with 

the nsks urcreasmg as the exposure 

mcreases. EPA's approach to nsk assessment for 

suspected carcmogen:s may be diVIded 

mto·severalsteps. The first 1s qualitative evaluation of the eVIdence to determJDe 

whether a substance should be 

constdered a human carcmogen for 

regulatory purposes. This was done for 

radionuclides before they were listed as , a hazardous air pollutant m 1979. The 

second step IS quantitative: how large lS 

the nsk of cancer at vanous levels of 

exposure? The result of tlus ex8ID!Dation 

IS a dose-response function which gJ.Ves the lifetime nsk per unit of exposure (or "potency"). The third step 1s to estimate 

how many people are exposed to the 

sources of radiation, and at what levels. 

These exposure estimates then are 

combmed with the dose-response function to obtam estimates of the nsk 

caused by emJsstons of the pollutant, m 

tlus case radionuclides, mto the 

envtronment. 

Exposure levels for each specific 

source category are denved usmg emiSSIOns estimates, dispersion modeling, and population data. For any 

gtven level of ellllSS!ons, dispers1on models predict concentrations at 

different distances from the ellllSSton 

source. By combmmg those estimated 

concentrations with census data on .population densities, the number of 

people exposed at different levels can 

be estimated. Several factors suggest that actual exposure levels will be lower 

than those estimated. In estimating 

exposure, the most exposed mdivtduals 

are·hyp.othetically subJected to the 

m8Xl.Ulum annual average concentration 

of the em~ss1ons for 24 hours every day for 70 years (roughly a lifetime). Th1s 

does not take mto account mdoor vs. 

outdoor all, for mstance, or the fact that 

most people m thelf daily routines move 

m and out of the specific areas where 

the em1sS10n concentration are the 

h1ghest. 

The final nsk estimates are the 

product of the exposure levels and the 

estimated unit-r1sk factor. Two summary 

- measures are of particular interest: 

"nearby mdivtdual nsk" and "total 

population 1mpact.'' The former rofors to 

the estimated mcreased lifetime rlsk 

from a source that ts faced by mdlvtduals who spent thmr entire liCe at 

the pomt where predicted concentrations of the pollutant aro 

lughest. Nearby mdivtdual risk is 

expressed as a probability: a risk of one 

m one thouslind, for example, means 

that a person spending a lifetime at tho 

pomt of max1mum exposure faces an 

estimated mcreased r1sk of cancer of 

one m one thousand. (For compar~son, 

the average lifetime nsk of dying of 

cancer m the United States is about 165 

m 1,000, so elimmating a nsk of one in 

one thousand reduces the overall 

lifetime r1sk of contracting cancer by less than 0.6 percent.) Estimates of 

nearby mdivtdual nsk must be 

mterpreted cautiously, however, slnco 

generally few people res1de at the points of max1mum concentrations and spend thelf whole lives at such locations. 

The second measure, "total 

population unpact," considers people exposed at all concentrations, low as 

well as hJ.gh. It 1s expressed in terms of 

annual number of cancer cases, and 

prov1des a measure of the ovoralllmpact 

on public health. A total population 

lDlpact of 0.05 fatal cancer per year, for .example, means that emlss1ons of tho 

specific pollutant from the source 

category are expected to cause ono cuao 

of cancer every 20 years. Such figures should not be viewed as precise estimates of tha.Jikely effects. Together with the estimates of max1mum 

mdivtdual nsk, they are mtended to give 

an mdication of a reasonable upper-limit situation. 

The two estimates together provide a 

better descr1ption of the magnitude and 

distribution of nsk m a community than 

either number alone. "Nearby indlv!dunl 

nsk" tells us the highest risk, but not 

how many people bear that risk. "Total 

population 1mpact" describes the overall 

health ~mpact on the entire exposed population, but not how much mk tlto 

most exposed persons bear. Two 

sources of radionuclide or chem1cnl 

ellllSS!ons could have s1milar population 

lDlpacts, but very different maximum 

mdivtdual nsks, or v1ce versa. Any sanslble "r1sk management" system 

cannot rely on either measure alono; both are tmportant. 

Much more 1s known about tho risks 

from exposure to radiation thllD 

exposure to most chem1cols. While there 

1s uncertamty m rtsk estimates from 

assessments of chem1cal emtssiona and 

radlonuclide emtss1ons, there 18 likely to 

be much less uncertomty In eslimotes of 
Federal Regtster I Vol. 49, No. 2.12 I Wednesday, October 3.1, 1984 I Proposed Rules 

nsk from radionuclide e!Dlsstons 

because of the extens1ve data base on 

human exposure to radiation. Therefore. 

a nsk estimate of one m one thousand 

resulting from radionuclide e!DlSSlons 1s 

likely to be more accurate than the same 

estimate for chemtcal releases. The 

situation for estimating nsk from 

radionuclides lS much less likely to 

reflect hypothetical maxunum potential 

estimates than are estimates made for 

chemtcal emlSSIOnS. 

~ To proVlde general perspective 

regarding radiation exposure, everyone 

IS exposed to background radiation due , 

to cosmtc ra-diation, and radioactivity m 

mlneral~ soils. and even our own 

bodies. Background radiation levels 

vary across the U.S., but average about 

100 mrem/y for each person. There IS 

very little that people can do to control 

exposure to background radiation. Over 

a lifetime thls exposure 1s estimated to 

contribute to a fatal cancer nsk of about 

one or two cases for every one thousand 

people. 

VTI. Withdrawal of Proposed Standards 

A. Alternatives 

In detenmrung the appropnate course 

of action for the proposed standards, 

EP~ constdered the followmg 

alternatives. 

1. Withdraw the Proposed Standards 

Thls alternative IS based on the 

finding that current and future enusstol)s 

at the facilities under consideration are 

antiCipated to be at levels that would 

protect the public with an ample margm 

of safety, as reqwred by section 112 of 

the Act. Thls alternative lS also 

appropnate if implementation of the 

proposed standards IS mfeasible. 

2. Promulgate the Proposed Standards 

Thls alternative ts based on the 

conclusion that the findings made m the 

proposed rule were correct and that the 

proposed standards are necessary to 

adequately protect the public health. 

3. Promulgate a Standard for Each 

Category at a Level That Would Limit 

Dose to 25 mrem/y to the Whole Body 

and 75 mrem/y to Any Organ 

Thls alternative lS based on the 

concluston that ihe need for standards 

for each category for which the Agency 

proposed rules was correct. but that 

EPA could establish the standards at 

these recommended levels and still 

proVlde an ample margm of safety. 

Establishmg the standards at these 

levels would also respond to several 

comments regarding consistency among 

the categones and with the 

recommendations of recogruzed national 

and mtemational radiation protection 

groups, and regarding the need for 

greater operator flexibility m selecting 

control technology and methods or 

demonstraUng compliance. 

B. Elemental Phosphorus Plants 

One of the dects1ons presented by thts 

rulemakmg concerns emtsston for 

elemental phosphorus plants. Risks from 

these plants are lugher than for any 

other source category m thls rulemakmg 

except uraruum mlnes. Moreover, 

techiJology to reduce these nsks ts 

available. Nevertheless, after 

constderaUon of the proposed rule, the 

public comments, the Sc1ence AdvJsory 

Board report. the nsk assessment, and 

other pertinent mformation. it JS the 

Admmtstrator's Judgment that the 

present record does not support a 

concluston that regulation of elemental 

phosphorus plants 1s necessary to 

protect the public health, withm the 

meanmg of the Clean Atr Act. Therefore, 

the proposed rule ts withdrawn. This 

deCisiOn presents difficult questions and 

the Agency IS undertakmg a number of 

nonregulatory actions, explamed below, 

that may lead to reex8mlnation of thls 

dectsJon at some future date. 

EPA estimates the total nsk to humo.n 

populations posed by radionuclide 

em~sstons from elemental phosphorus 

plants to be 0.06 fatal cancer per year, or 

approXImately one case every seventeen 

years. Thts nsk JS sunilar to other r1sks 

that EPA has constdered msuffic1ent to 

warrant Federal regulation m 

comparable Section 112 proceedings. 

About 80% of the total nsk presented by 

the mdustry IS accounted for by two 

plants, the FMC plant m Pocatello, 

Idaho, and the Monsanto plant m Soda 

Spnngs. Idaho. 

In the case of one of the plants, EPA 

estimates the dose rate to mdivJduals at 

the location of lugbest all' 

concentrations to be about 600 mrem/y 

to the lung. The chance of getting cancer 

from a lifetime of exposure at tlus 

location ts calculated to be about one m 

one thousand. If nsk to the "most 

exposed mdiVIduals" were the only 

critenon for JUdgment. tlus relatively 

lugh nsk m~ght well have led to a 

deciSton to regulate. 

However, thts nsk must be wetghed 

agamst both the low aggregate r1sk 

described earlier and agamst other 

factors. Our studies mdicate that 

present e!Dlsston controls on these 

plants are not effictent m remoVIng 

radionuclides and could M lUlproved. 

However, adding such additional 

controls will be expensive measured 

agamst the limited public health benefits 

provtded. 

Finally, the SAB Subcommittee's 

report harshly critiCIZed EPA's analysts 

m support of its proposed standards. 

That alone would not JUStify a deoston 

not to regulate, bulm tlie context of the 

limited aggregate nsk and other factors 

described earlier it contributes to such a 

dectston, particularly giVen the Scence 

AdVIsory Board's statutory role as the 

Agency's soence adv1sor. 

Over the next several years, EPA \~ill 

work with the Scence AdVISory Board 

to satisfy its concerns regarding the 

sctentific basts of regulations such as 

thiS. Undertakmg thls effort will also 

allow the development of answers to the 

followmg two questions that may have a 

beanng on any future EPA action. 

1. EPA 1s curently recoDSidermg its 

amb1ent 811' quality standard for 

particulates, and may shift its emphasis 

toward regulating the smaller-siZed 

particles. Since the two elemental 

phosphorus plants bemg coDSidered 

here emit large amounts of these smallar 

particles, they may reqwre additional 

controls based on these new standards. 

Luniting enuss1ons of these smaller 

particulates would also control some of 

the radionuclide em1Sstons from the 

plants. 

Z. The area surrounding these two 

plants 1s charactenzed by lugh total 

levels of radiation from a vanety of 

sources. The storage and \Vldespread 

use of slag and possibly other waste 

products from these plants have 

stgnificantly mcreased the natural 

background radiation levels m parts of 

the communities. In particular, 

phosphate slag from these plants bas 

been \Vldely used as aggregate in road 

and house construction m these areas. 

EPA and the State ofldaho mtend to 

perform a total assessement of the 

vanous sources and will mvestigate 

ways to reduce or prevent ruks from 

growmg. Tlus assessment may find more 

effective ways to control the overall 

nsks than by controlling the CmlSStons 

at 1ssue here. 

C. Department of Energy [DOE} 

Facilities 

It ts also the AdmlOistrator's Judgment 

that the present record does not support 

a concTuston that regulation of DOE 

facilities for radio-nuclide em~ss1ons to 

811' is necessary to protect the public 

health with an ample ma.rgm of safety, 

witlun the meanmg of the Clean Air Act. 

Therefore, the proposed rule ts 

withdrawn and the rulemakmg ts 

termmated. 

EPA estimates the total nsk to 

exposed human populations by all DOE 

facilities for whtch regulation was 

'Proposed as 0.08 'POtential fatal cancer 
43912 Federal Regu;ter I Vol. 49, No. 212 I Wednesday, October 31, 1984 I Proposed Rules 

per year, or one case every 13 years. 

Th1s nsk 1s comparable to nsks that 

EPA has cons1dered msufficiertt tn 

warrant regulation in Similar Section 112 

proceedings. 

Dose rates from the four DOE 

facilities with the greatest radioiii.lclide 

em1ss1ons range from 50 rmem/y to sa 

mrem/y to the lung; one of these 

facilities deliver.r a dose rate of 34 

mrem/y to the whole body. EPA 

estimates the chances of fatal cancer 

from a lifetime of exposure to these 

plants' most concentrated emlSSl.ons are about one to·e1ght m ten thousand, 

somewhat lower than the max.unum 

r1sks elemental phosphorus plants. Once 

a gam, trus nsk to nearby mdiVJduals 

must be we1ghed both agamst the law 

aggregate nsks and the SCience 

A.dv1sory Board report described earlier. 

The DOE currently has a program to 

keep exposure to the public. to levels 

that are as Iow as reasonably 

ach1evable. 'flus program a operated by 

the Department m keepmg \'llith the 

longstanding. recommendations of the 

National Council on Radiation 

Protection and Measurements, the 

International Comnuss1on on 

Radiological Protection, and the Federal 

Radiation Council to av01d radiation, 

exposure where practical. Whi!e the 

Agency recogruzes that DOE facilities 

mamtam very large quantities of 

radionuclides m the1r mventones. at 

many of the1r facilities, there has been .a 

general trend at most facilities for 

radionuclide em1ssions to be reduced 

over the years. Em1ss1ons should not 

Sl~nificantly increase in the future. EPA 

mtends to continue its oversight of 

em1ss1ons from DOE facilities and 

should this change, the ·Agency will 

reexanune its dects1on not to regulate. As prevtously noted, EPA currently 

has a Memorandum of Understanding 

(MOU} with DOE regarding the 

development and implementation of 

standards under section 112. EPA 

mtends to coordinate with DOE to seek 

to modify the Memorandum of 

Understanding as appropr1ate. 

D. Nuclear Reculatory Commission 

(NRC)-Llcensed Facilities and Non-DOE 

Federal Facilities 

It 1s also the Admm1strator's judgment 

that the present record does not support 

a conclus1on that regulation of NRClicensed facilities and Federal facilities 

other than DOE facilities ts necessary to 

protect the public health with an ample 

margm of safety, within the meaning of 

section 112."Therefore, the proposed rule 

18 withdrawn and the rulemaking 1s 

tenmnated. 

EPA estimates the total nsk to human 

populations posed by NRC-licensed 

facilities·andnon-DOE Fed:eraJ facilities 

for which regulations were proposed fo 

be no more than o.oz fa fat cancer per 

year, or less than one case every fifty 

years. Tins nsk 1s comparable to other 

nsks that EPA has cons1dered 

msuffic1ent to warrant regulation m sLmilar Section 11Z proceedings. 

EPA calcalates the changes of 

developmg fatal cancer from a lifetime 

of exposure to the most concentrated 

emiss10ns from the NCR facijitiyw:ith 

the greatest dose rate at na more than 

two m ten. thousands. EPA believes that 

the Nuclear Regulatory ComD1Jss1on and 

other Federal facilities will continue to 

lm.Plement programs to keep exposure of 

the public to levels that are as low as 

reasonably acluevable. and adeqtiate to 

protect the public a.g.amst SJgnificant ' 

adverse effects from radiation:. 

Etm3stons should not Significantly 

mcrease m the future. EPA will continue 

its ovecnght of emisSJoas from these 

facilities, and should this change, the 

Agency will reexamme its deetSJon not 

to regulate. 

As prevtously noted EPA currently 

has a Memorandum of Understanding 

(MOU) with NRC regardiDg the 

development and lDlplementation of 

standards under section U2. EPA 

mtends to coordinate with NRC to seek 

to modify the Memorandum of 

Understanding as appropnate. 

E. Undergrounc! Urammum Mines 

The Agency proposed a standard for 

underground uranimum mines that 

would limit the annual average radon222. concentration in at.r due to enussions 

from an underground mme to O.Z pCi/1 above background m any unrestricted 

area. The standard was expected to be 

met by one of the foltowmg procedures: 

(1) Reducmg the precentage of time the 

mme operate g. (2J fncreasm.g the 

effective hetght of the release, and {3) 

controlling additional land. EPA 

expected that nnne operators would 

most likely try fo control land witlun 

about 2 kilometers of the mme vents m 

order to comply with the standard. EPA 

did not issue a direct emJssxon standard 

for radon from underground uranmm 

mmes because. as the proposal 

explamed, available mformation 

suggested that radon could not be 

collected by available pollution control 

eqwpment before bemg released from 

the vents, rednction9 afforded by better 

bulkheading or seaTanfs were lughly 

uncertain, and reducmg the volume-of 

atr flow was not feasible due to the 

effect on occupational exposure. 

Comments on the proposed rule 

mqicated Jhat controlling a sufficient 

amount of land m1ght-not be feasible 

because pnvate owners of land 

surrounding the mine-might be unwilling 

to make then· land available ta fhO' mma 

ownel'!t. 

Several comments were recmvcd 

starting that EPA had overestimated the 

nsks from radon·22Z em1ss1ons from 

underground uranium mtnes. It was. 

suggested thaf the Agency had used 

overly conservative assumptions m the 

dispemon and rlsk caiculntiona nnd thut 

it used greater r1sk coefficients thnn 

recommended by other recogmzed 

radiation experts. EPA has cons1derod 

these comments m establislung its 

parameters for eiillSSIOn rnte~plume 

nse, and equillbr1um raUos tn the 

rev1sed nsk assessment. The most 

recent estimates of the lifetime risks to 

mdividuaJs Iivmg near these mme runge 

from one m one. thousand to one in one 

hundred. The potential ex.JSts for even. 

}ugber nsks m some situations, e.g .. a 

person livmg very close to several 

honzontal mmes vents or in areas 

mfluenced by multiple mine emissions. 

Lifetime rtsks m these situations could 

be as high as one in ten. EPA estimates 

the fatal cancer r1sk to the total 

population to be nboutfive fntal cancers 

per year. The Agency constders these 

nsks to be stgnificanf nndbelieves 

action 1s needed to protect popu!nlions 

and mdiVJduals livmg near underground 

uraruum mmes. 

AnalysLS of the likely reduction. m 

health nsJcs afforded by the proposed 

standards showed that while nsks to 

neatly mdiVlduala were reduced by a 

factor of abaut ten, the raoks to the total 

population were only neg.Ugibly reduced. 

The lack of population r1sk redaction ls 

due to the fact that radon ~:eleoscs 

would not be reduced by the proposed 

rule, they would only be more wldoly 

dispersed. 

EPA bas concluded tbat its proposed 

standard was legally flawed m two 

ways. First, because it would not ha.va 

limited radionuclide enusSlons on a 

continuous baSts, but was pnmarily 

based on the use of dispersion 

technology to reduce nsks to nearby 

people, it did not quall!y an "eiDlSSIOn 

standard'' withm the meaning of section 

112 (See Clean A1r Act, section aoz(k)]. 

EPA also believes such dispersaon 

techn1ques cannot qualify in tJug context 

as a "des1gn, equ1pment. work practico 

or operational standard .. within the 

meanmg of section 112(e}. BPA believes 

that for such standards to be valid, they 

must also have- an emtsston limiting 

effect. (See Clear A1r Act, secUontJ 

11.2(e)(3) and (e)('.l).) Second, because 

tlus standard would not reduoo the 

aggregate population risk apprectnbly, 

when such nsk waS' lugh, if foiled to 
Federal Register I Vol. 49, No. 212 I Wednesday, October 31, 1984 I Proposed Rules 43913 

meet the public health protection 

purposes of the Act. 

Because radon-222 1s a-noble gas and 

the volume of rur discharged through 

mme vents 1s very large, there 1s no practical method to remove radon-222 

from the mme exhaust a1r. Adsorption 

onto activated charcoal1s the most 

wxdely used method for removmg noble 

gases from a low volume a1r stream. 

However, application of thts method to 

the removal of radon-222 from mme ventilation au at the volumes of a1r 

wlnch must be treated would reqwre 

large, complex, unproven systems wlnch 

would be extremely costly (i.e., at least 

$18-44/lb ofU30a produced). 

Since proposal, EPA has rece1ved 

additional techrucal mformation m a report prepared for the U.S. Bureau of 

Mines, mdicating that work practices, 

such as bulkheading abandoned 

sections of mmes to trap the radon 

before it Is vented, may be more feasible 

and cost-effective than preVIously 

thought. Tlns mformation, wlnch 1s of a prelimmary nature, suggests that 

bulkheading, even without the use of 

charcoal filters, could reduce enuss1ons 

of radon-222 by 10-60~ from typ1cal mmes at a cost rangmg from $4-$60 per cune reduced or about $0.01-{).05/lb of 

U30i produced. 

Uraruum mmes are wtdely diverse m the1r charactenstics. They differ m configuration; for example, some mmes have very few s1de tunnels and cross 

cuts whereas others may have m.any 

stde areas. Consequently, they have a 

wtde vanety of surface areas where 

radon can be generated. In addition. mmes differ in the geologic strata, 

IIlliWlg tecbruques, and uranium and 

radium concentrations. All of these 

factors tend to decrease the number of 

common charactenstics among mmes 

that can be used to make general 

predictiOns of the effectiveness of 

specific control measures. Therefore. 

considerable additional work ts needed 

to establish whether these results can be 

realized consistently for an appreciable 

segment of the mdustry, and to 

determme methods of bulkheading that 

might potentially produce any such 

consistently acceptable results. Only 

after these facts have been established 

would EPA be able to propose a standard based on these techmques. In 

any event, no such rule can be 

promulgated on the present record 

because the on,gmal proposal cons1dered the use of.tlns form of 

control and explicitly dismised it as a bas1s for the st.andard. 

Because the Agency ts convmced that 

the health nsks posed by underground 

uraruum mmes are s1gnificant, EPA has 

dec1ded to begin developing an 

emission, des1gn, eqwpment, work 

practice, or operational standard to 

control radon releases from 

underground uraruum mmes. An 

Advance Notice of Proposed 

Rulemakmg announcmg tlns dec1s1on IS 

being published simultaneously with 

tlnsnotice. 

vm. Fmal Determmation for Sourcos 

EPA Proposed Not To Regula to 

EPA preVIously tdentified several 

source categones that emil 

radionuclides to a1r but proposed not to 

regiilate them. Final dec1s1ons on the 

need for emiSSIOn standards for these 

categories, and the reasons for these 

dec1s1ons, are discussed m the followmg 

paragraphs. 

A. Coal-Fired Boilers 

Large coal-fired boilers are used by 

utilities and mdustry to generate 

electricity and to make process steam 

and hot water for space heaters and 

mdustrial processes. When operating, 

these boilers emit trace amounts of 

uraruum, radium, thonum, and the1r 

decay products found m the feed coal. 

These radionuclides become 

mcorporated mto fly ash and are earned 

mto the rur along with the particulate 

matter these boilers emiL Technology 

that removes particulates will also limit 

radionuclide emiSSions. 

Particulate emiSSions from new utility 

and new large mdustrial boilers are 

controlled by new source performance 

standards tssued under Section 111 of 

the Clean Air Act reflecting best 

demonstrated technology. EPA has aJso 

proposed new source performance 

standards for smaller mdustrtal boilers. 

Existing utility and mdustrial boilers are regtdated for particulate eiJUSSIOns by 

State Implementation plans as reqwred 

by the Clean Air AcL 

EPA proposed not to regulate coalfired boilers because these eXJsting 

particulate emiSSion standards aJso limit 

radionuclide releases, and result m relatively mstgnificant nsks to nearby 

mdiVIduals and to populations due to 

radionuclides. The lugheat dose 

resulting from tlns source category 1s 1 

mrem/y to the lung. Tlus 1s eqwvalent to 

an mdiVIduallifetime nsk of fatal cancer 

of one m one million. Population nsk 1s 

estimated to be about two fatal cancers 

per year, spread over tlie entire U.S. 

population. The cost to further reduce 

radionuclide emissions ts greater m companson to the additional pubUc 

health protection aclneved. In addition, 

radionuclide emissions will decrease as old plants are replaced with new ones havmg tmproved particulate emiSSion 

controls as requued by the Clean Air 

Act. 

M3ny com.menters, mostly mdustrial 

groups, strongly supported the 

determmation not to propose regii!atio£1.5 

for tlus source category. Several 

commenlers stated that the nsks from 

coal-fired boilers were so low that tlns 

fact aJone mdicated that standards are 

not needed. The Agency's deCISlon not 

to regulate 1s based on both a 

consideration of the level of nsk and on a consideration of total cost and 

practicality of additional control 

eqwpmenL Some com.menters stated 

costs should not be constdered under 

section 112 of the Clean Atr Act. EPA 

beUeves it 1s not reasonable to avotd 

cons1denng cost and practicality of 

control technology; however, the 

protection of public health was the 

pnmary consideration m reaching tlns 

deCISIOn. 

Some commenters ra.Jsed the question 

of whether there are some boilers that 

miSht bum coal with lugh uramum 

content, leading to euuss1onlevels far 

greater than those considered m makmg 

tlns detemunation. EPA asked for ·comment on tlns pomt and contracted 

with Los Alamos National Laboratory to 

mvestigate the existence of such boilers. 

The Agency was unable to find boilers _ 

with radionuclide euuss1on rates 

Significantly greater than the model 

facility we studied tn detail In fact. the 

ma)ority of boilers can be demonstrated 

to have emiSSIOns much lower. 

Some com.menters stated that the 

reqwrements of the Clean Air Act 

dictate that EPA must propose an em1ss1on standard specifically for 

radionuclides, regardless of other Clean 

Air Act regulations limiting particulate 

emiSSions. EPA believes that to ISsue a 

standard that duplicates 'Current 

regulations IS unreasonable. As a 

practical matter, Clean Air Act 

regulations limiting particulate 

emiSSions from these boilers also limit 

radionuclide emiSSIOns. Hence. these 

existing regulations protect the public 

health with an ample margm of safety as 

far as rodionuclide eDl1SS1ons are 

concerned. 

After carefully cons1denng all 

comments, EPA has decded not to 

regulate radionuclide em.tSSlons from 

coal-ftred boilers at tlns time. Tlus 

dects1on will be penodically reVIewed as additional mformation on the total 

tmpact of all hazardous cur pollutants 

from coal-fired boilers becomes 

available. 

B. Phosphate Industry 

The phosphate mdustry processea 

pbos.(?bate rock to produce fertilizers. 

detergents. antmal feeds, and other 

products. The production offertilizer 
43914 Federal Regl3l2r / VoL 49, "No. 21.2 I Wednesday, October 31, 1984 I Proposed Rules 

uses approxtmately ao percent of the 

phosphate rock mmed m the United 

States. Phosphate deposits contam 

elevated quantities of natural 

radioactivity. pnnc1pally uraruWJl.23S. 

and members of its decay sertes. 

Uraruum concentrations m phosphate deposits range from. ten to one hundred 

times the concentration of uraruum m 

other natural rocks and soils. 

Phosphate Rocl~ Processing Planls 

The processmg of phosphate rock m 

dryers, gnnders, and fertilizer plants results m the release ofradionuclides 

mto the air m the form of dust particles. Control techniques that remove 

particulates will also control 

radionuclide enuss10ns. 

Particulate enuss1ons from new or 

modified phosphate rock drymg, gnnding, and fertilizer plants are 

controlled by new soW'Ce performance 

standards issued under Section 111 of 

the Clean A.Jr Act In the case of 

fertilizer plants, the nelv source 

performance standard for finonde also 

provides for effective controf of 

particulates. Existing dryin~r. gnnding. and fertilizer plants are regulated for 

pa.rticulate emiSSions by State 

Implementation pfans as required by the 

Clean A.Jr Act. EPA proposed not to 

regulate phosphate rock processing facilities because the eXIsting particulate and fluoride emss1on 

standards arso limit radionuclide 

releases. The nsks fo nearby mdiVlduals 

and the total population risks due fo 

radionuclide enusstons from these three 

types of facilities are ms1gnificant. The htghes~ doses resulting from emisstons 

from these facilities are.15 mrem/y to 

the bone and 7 rmemfy to the lung. This 

1s eqmvaient to a lifetime mdividuai nsk 

of fatal cancer of one m one htmdred 

thousand. Population risk IS. from all of 

these facilities about to 0.02 fatal cancer 

per year. In addition. there lS no 

potential for ennsSions to mcrease; 

rather. they'should decrease as older 

plants are replaced with new ones 

subJect to new source perl'oxmance standards. 

Comments from the phosphate mdustry strongly supported EPA's proposal not to regulate phosphate rock 

processmg facilities- and further stated 

that EPA had overestimated the 

radionuclide enusSions from these 

facilities. EPA agrees that its estimates 

of radionuclide el'IllSstonlJ from these 

facilities were based on some 

conservative assumptions and has concluded that thts serves to remforce 

its dec181on not to regulate these 

facilities. 

Several commenters stated that 

standards were needed for phosphate 

rock processmg facilitias and that co:Jt 

sliould not be constdered m reacbmg a 

dectslon on the need for these 

standards. Even without cons1detmg 

costs, EPA doe!! not agree that 

standards are needed for these: facilities 

for the reasons JUSt stated. 

EPA did not preVIously make any deternunation regarding radionuclide 

standards for-phosphate rock calciners 

at wet process fertilizer-plants because 

mformation on eJPlSsions from these 

facilities was not available. EPA 

requested comments on these etmSsxons 

and asked whether standards were 

needed. In addition. the Agency conducted emxsswn tests at two of these 

facilities. EPA has not yet completed its 

analysis of these emiSSIOn tests or 

earned out a nsk assessment for these 

calcmers. Therefore, no defermmation of 

the need for standard$ for phosphate rock calcmers at wet process fertilizer 

plants IS made at tlus time. 

After considenng all comments. EPA 

has deCided to affll'lD and make final its 

deciSion not to regulate radionuclide 

enusstons tram phosphate rock 

proces.smg plants. other thau phosphate 

rock calcmers at wet process. fertilizer 

plants. A deCISIOn regarding the need for 

standards for this latter source \•Jill be 

made after completion of the Agency·~ 

analys8$ of enuss1ons and nst-.s from 

these facilities. 

PhosphogypsumPiies. 

Several comments were received 

requesting EPA to iSsue stanclartbt under 

the Clean Alr Act for radionnclide 

emiss1ons from phospbogypsum piles (fertilizer plant waste matenalt. EPA did 

not propose radionuclide standards for 

t1ns source because it believed that such 

wastes would be more appropnately 

regulated under the Resource 

Conservation and Recovery Act (Pub. L. 

94-580). 

After coDSidenng all commen~ EPA 

lS reevaluating the need for radionuclide 

standards for tius sourc~ Prelirmnary nsk estimates mdicate that 1npj.qidual 

lifetime nsks from exposure: to mr em~ss1ons from. these piles may be as 

lugh as ezght m ten thousand. Population nsks may be OII the order of on~ fatal 

cancer per year. The.A.,<18ncy will 

continue its exannnation of the need for a standardforthr~somce category. 

C. Otfler Extraction Industries 

Almost all mdustnal operations 

mvolvmgremoval and processmg of 

soU:t and rocks to recover mmeral 

resources release some radionuclides 

mto the atr. EPA has conducted studies 

of a1rbome radioactive eiiUSSions from 

the mmmg, milling. and smelting of 1ron, 

copper, zmc, clay, limestone, fluorspar. 

and bauxite. These are relatively lo.r&O' 

mdustnes and are con:ndcred to have 

the greatest potential for rur eml!ISIOno 

of radionuclides. 

EPA proposed not to regulate these 

extraction mdustneu bee3use the 

available data showed that the rtslw to. 

mdivtduals and population:; from 

radionuclide emJSmons from the:::e 

facilities are mstgnificant.lndividuul lifetime ns!:s range from one In one 

hundred million It> one m ten thousand. 

Population nsb range from 0.000001 to 

0.01 fatal cancer per year. 

Most of the comments rece1ved wore 

from mdustry representativctJ who 

concurred with EPA"s proposal not to 

regulate these facilities. In thetr opmlon, enuss10ns, doses, amf risks were so 

small ibat a regulation was unnecessary. 

No ne\17 mfonnation was provided to tho 

Agency dunng the public comment 

penod wlnen mdicatecf a need for 

standards. Additional Agency studios 

have confirmed that radlonuclida 

ennss1ons from these sources are low. 

After cons1dermg all comments, EPA· has demded to affirm and make final it~ 

deciSion not to regulate radionuclido 

enuss1on8' from extraction mdustry 

facilities. 

D. Uranium Fuel Cycle Facilities, 

Uramum ll.fill Tailings, one! 

Management of High-Level Radioactive 

Waste 

The uramum fuel cycle consists of 

operations associated wilh production of conunere1ai electric power by IIebl 

water reactors usm~ uran1um fuel. It 

mcludes nuclear power plants and 

facilities that mill uranium ore. procen uranium. and fabricate and reprocess 

urantum fuel. EPA haa promulgated 

em1ss1on standards for normal 

operations o£ the uranium fuel cycla under the Atomic Energy Act (40 CFR 

Part 190}. These standards Umil the 

annual dose eqwvalent from 

radionuclide enusSJons to 25 mrem{y to. 

the whole body and to any organ. wlth 

the exception o! the thyro1d, which may rece1ve 7& rmem/y. EPA standards and 

thetr tmplementation by the NRC require 

the use of available technology wh1ch 

resulfs m low doses to !'ndivJduals and 

populations. 

Many commenters, both government and mdustry. supported EPA's decision 

not to Issue enusston standards fot thlo 

source category. Other commentero felt 

that the ClennA.Jr Act requ~res EPA to 

set emtss1on standards for uranium fuel 

cycle facilities, regardless of any other 

standards m force 

The Agency believeo that current EPA 

standards for the uranium fuel cycle provtde a level of protection whtch ~ 
Federal Regtster I Vol. 49, No. 212 I Wednesday, October 31, 1984 I Proposed Rules 43915 

satisfies the reqwrements of the Clean 

.Alr Act. An ennssion standard 

promulgated under the Clean Air Act 

would be duplicative 'vith the uramum 

fuel cycle standard and would not offer 

any additional public health protection. 

Dunng the Agency's upconung reVIew of 

40 CFR Part 190, t1us Issue will be 

reexammed. 

Uraruum mill tailings remam after 

uranium IS removed from the ore. Many 

thousands of acres of these tailings eXIst 

at both mactive and active uramum mill 

sites, located mostly m the WesL The 

high concentration of radium-226-m the 

tailings can -result m sigDificant emiSSion 

or radon-222, a radioactive gas. Under 

current EPA disposal standards which 

reqwre long term stabilization of the 

tailings piles, 95% or more of the random 

emissions will be controlled. These 

standards, lSSued under the authority of 

the Uranium Mill Tailings Radiation 

Control Act of 1978 (Pub. L. 95-004}, 

proVIde a level of public health 

pJOteclion comparan1e to an 811' 

emission standard. 

However, commenters noted that 

randon emiSSIOns from the tailings piles 

at licensed uramwn mills are exempted 

from the reqwrements of 40 CFR Part 

190. They are controlled, mstead. by 

NRC regulations which allow a concentration of SpCi/1 of radon-222 m 

unrestncted areas. Tlus value represents 

a level of nsk that may be sigllificant. 

EPA lS publishmg, sunultaneously with 

this notice, and Advance Notice of 

·Proposed Rulemakmg to consider the 

need for an emlSSlon standard for radon 

emisSion from licensed nramwn mills. 

Highly radioactive liqmd or solid 

wastes from reprocessmg spent nuclear 

fuel, or the spent fuel elements 

the~nselves if they are disposed of 

without reprocessmg, are conSidered 

high-level radioactive waste. EPA has 

proposed standards l.Ulder the Atomic 

Energy Act to limit public exposure to 

the radionuClides m t1us :waste pnor to 

disposal and has proposed that 

operations be conducted to reduce 

exposures below the standard to the 

extent reasonably achievable. The 

Agency expects its standards for the 

management of high-level raaioactive 

waste to be promulgated m the near 

future. These standards will control 

eolissions durmg the operational phase 

of the disposal site to a level which 

results m a dose eqwvalent no greater 

than 25 mrem/y to the whole body or to 

any organ. except the thyrOid. which 

may receive a dose as lugh as 75 mrem/ 

y. Th.ese standards will proVIde a level 

of public health protection comparable 

to an emiSston standard 1ssued under 

the Clean Air Act 

After consideration of all comments. 

EPA afflrms and makes final its deCISIOn 

not to Issue separate standards under 

the Clean Ali' Act for radionuclide 

emlss10ns from. the uramum fuel cycle, 

uraruum mill tailings, and management 

of high-level radioactive waste. 

E. Low Energy Accelerators 

Accelerators unparl enezmr to charsed 

particles, such as electrons, alpha 

particles, protons, and neutrons. They 

are used for a ·wtde var1ety of 

applications, mcluding radiography, 

activation analysiS, food sterilization 

and preservation, and radiation theropy 

and research. Accelerators, other than 

those owned by the DOE. operate at 

comparatively·lo\v energy levels and 

therefore emit very small quantities of 

radionuclides. The doses and health 

r1sks associated with these emiSSions 

are extremely low. Lifetime mdiVIdual 

nsks range from one m ten trillion to one 

m one billion. Further, there ts no 

potential for the emiSSions from these 

facilities to mcrease Significantly. 

The Agency proposed not to regulate 

this category. No comments were 

recetved on this proposal, and the 

Agency 1s not aware of any new 

mformation mdicating a need Cor a 

standard. Therefore, the Asency affirms 

and makes final its deciSIOn not to 

regulate radionuclide emissions from 

low energy accelerators. 

IX. Miscellaneous 

Docket 

The docket 1s an orsaruzed and 

complete file of all mformation 

constdered by EPA m this rulemakmg.lt 

IS a dyna.nuc file, smce matenalls 

added throughout the rulemalang 

process. The docket allows interested 

persons to 1dentify and locate 

.documents so they can effectively 

partic1pate m the rulemakmg process, 

and it also serves as the record for 

JUdicial reVIew. 

Transcnpts of the beanngs, all written 

statements, the Agency's responses to 

comments, and other relevant 

documents have been placed m the 

-docket and are available. for mspectlon 

and COPYin& durmg normal workmg 

hours. 

Dated: October 23, 1984. 

\Wliam D. Ruckelsbnus, 

Admuustratcr. 

[FR Doc. &WMSa r.!cd lo-:G-&&: Z:U PI 

BIWNQ COO£ ~11 

40 CFR Part 61 

(AD-FRL 2694-23) 

National Emlszfon Standards for 

Hazardous Air PollutanW; Standzds 

for Radon·222 Emlssfons From 

Underground Uranium Mines 

AGENCY: Environmental Protection 

Asency (EPA). 

ACTJON: Advance notice of proposed 

rulema.lang. 

SUMMARY: This notice anD.OtlllCCS the 

Agency's mtent. under Section 11.2 of the 

Clean Air Act, as amended. to start a 

program to constder a standard based 

on bulkheadins or related techmques to 

control radon ennssions from 

underground -uranium min.es. This 

st3lldard could be an emission standard. 

or a design, equipment, work practice. or 

operational standard, or a combination 

thereof. The Asancy requests mterested 

parties to submit mformation and 

comments relative to controlling these 

emisstons. 

DATES: Information receJVed by Ap.rilao, 

1985 will be or maximum value. 

ADDRESS: Comments must be submitted 

(in dupUcate, if possible) to: Central 

Doclcet Section (LE-130) Attention: 

Docket No. A-79-11, EnVIronmental 

Protection Asency, 401 M Street. SW .. 

Washington, D.C. 20460. 

FOR FURTHER IHFORMAnON C01lTAC1: 

James M. Hardin, (703) 557-8977. 

EnVIronmental Standards Branch, 

Critena and Standards DiVIston (ANR460), Office of Radiation Programs. 

EnVIronmental Protection Agency, 

Washington. D.C. 20460. 

SUPP~ENTARYINFORMAnON:This 

Ad\'ance Notice of Proposed 

Rulemakms (ANPR) serves to mform 

mterested parties that the Agency is 

constdenns a rulemakmg related to the 

deSI:;n and type of eqmpment. work 

practices, operational procedures. or to 

emiSSion standards based on these 

techruques, to control the radon-222 

emisSions from underground uranimn mmes. As of January 1933, there were 139 or these mmes located m Arizona, 

Colorado, New Mexico. Utah. and 

Wyommg. These mmes have a 

production rate of 6,200 tons of ~Oa 

and account for about 46% of the total 

production of U30 8 m the United States. 

The Agency proposed a standard 

under section 112 or the Clean Air Act in 

April of 1983 for underground nranium mmes that would limit the annual 

radon-222 concentration m att due to 

emissions from an underground mme to 

0.2 pCi/1 above background many 

unrestnctcd area. The pnncpal method 
43916 Federal Reg1ster I Vol. 49, No. 212 I Wednesday, October 31, 1984 I Proposed Rules 

to meet thlS standard was constdered to 

be control ofland around the mtne, 

smce at the time, the Agency believed 

that no em1sston reduction measures 

were practical. 

In EPA's most recent evaluation of the 

rtsks due to radon-222 emtsstons from 

underground uramum mmes, the 

estimated lifetime nsk of fatal cancer to 

nearby mdivtduals ranges from one m 

one thousand to one m one hundred. 

The potential eXJsts for an even hlgher 

nsk m some situations (up to one m ten) 

for mdiVlauals livmg very close to 

several hortzontal vents or m areas 

mfluenced by multiple mme em~ss10ns. 

The fatal cancer nsk to the total 

population from radon-ZZ2 em1sstons 

from all underground uraruum mJDes 1S 

five fatal cancers per year. The Age:ncy 

constders these rtsks to be stgnificant 

and believes action 1s needed to protect 

mdivtduals liVlng near underground ' 

mmes and other populations. 

However, analysts of the likely 

reduction m health nsks afforded blj the 

proposed standard showed that, while 

rtsks to nearby mdivtduals were 

reduced by a factor of about ten, the 

mks to the total population were only 

negligibly reduced. The lack of 

population nsk reduction was due to the 

fact that radon releases would not be 

reduced, they would only be more 

wtdely dlspllrsed. 

The Agency dec1ded to withdraw its 

proposed standard for underground 

uramum m1nes based on its conclus1on 

that the proposed standard was not 

authorized by the Clean Alr Act and 

that the limited reduction m population 

rtsk would not meet the full mtent of 

·section 112 to prov1de adequate public 

health protection. 

Because radon-ZZZ ts a noble gas and 

the volume of a1r discharged through 

mme vents 18 very large, there ts no 

practical method to remove radon-~2 

from the mme exhaust atr. Adsorption 

onto activated charcoahs the most 

wtdely used method for remoVlng noble 

gases from a low volume atr stream. 

However, application of thts method to 

the removal of radon-222 from mme 

ventilation a1r at the volumes of a1r that 

must be treated would reqmre large, 

complex, unproven systems whtch 

would be extremely costly. 

Since proposal. EPA has rece1ved 

additional mformation mdicating that 

work practices, such·as bulkheading, are 

more feasible and cost-effective than 

ortgmally thought. The Agency has 

dectded to begm development of 

standards based on bulkheading or 

sunilar techmques to control radon 

releases from underground uran1wn 

mmes. Interested parties are reque&led 

lo submit mformation and comments onthe followmg 1ssues: 

(1) Measured or estimated radon-ZZZ 

releases from wdergrowtd mmes; 

(Z) Applicable standard.!' for reducmg 

radon emiSSIOns. mcluding such 

practices as bulkheading, sealants, mme 

pressunzation, and backfilling: 

(3) Methods of procedures to predict 

releases of radon-222 without controls 

and with controls, such as bulkheadlng, 

sealants, mJDe pressuriZation, and 

backfilling; 

(4) Effectiveness, feasibility and costs 

of controls; 

(5) Methods of determmmg 

compliance with destgn, eqwpment, 

work practice, or operational type 

standaros; 

(6) Estimates of tmpacts on nearby 

mdlv1duals and populations due to 

radon-222 em1ss1ons before and after 

control: 

(7) Extent of radon-222 controls now 

practiced by the mdustry, mcluding such 

methods as bulkbeading, sealants, mJDe 

pressurtzation, and backfilling; and 

(8) Effect on the mdustry if controls 

are required. 

Dated: October 23, 1984. 

Wllllam D. Ruckelshaus, 

Admm1strator. 

(PR Doc. 84-211$39 Filed 1~; t:13 pm] 

BIWNG CODE 656C)-,50-N 

40 CFR Part 61 

[AD FRL 2694-2bl 

National Em1ss1on Standards for 

Hazardous Air Pollutants; Standards 

for Radon-222 Emissions from 

Ucensed Uramum Mills 

AGENCY: Environmental Protection 

Agency (EPA). 

ACTION: Advance notice of proposed 

rulemakmg: 

SUMMARY: This notice announces the 

Agency's mtent, under section 112 of the 

Clean Alr Act, as amended, to constder 

development of standards to control 

radon-222 emissions from licensed uraruwn mills. The Agency requests 

mterested parties to submit mformation 

and comments relative to controlling 

these em1Ss1ons. 

DATES: Information rece1ved by April 30, 

1985 will be of maxtmwn value. 

ADDRESS: Comments must be submitted 

(in duplicate, if possible) to: Central 

Docket Section (I.E-130) Attention: 

Docket No. A-79-11, EnVlronmental 

Protection Agency, 401 M Street, SW., 

Washmgton, D.C. 20460. 

FOR FURtHER INFO~MATION CONTACT: 

James M. Hardin, (703) 557~977, 

Envtronmental Standards Branch, 

Criterta and Standards Division (ANR ... 

460), Office of Radiation Programs, 

Envtronmental Protection Agency, 

Washmgton, D.C. 20460. 

SUPPLEMENTARY INFORMATION: This 

Advance Notice of Proposed 

Rulemakmg (ANPR) serves to Inform 

mterested parties thot the Agency Is 

constdermg emtss1on standards undor 

the Clean Alr Act for licensed uranium 

ore processmg facilities. As of January 

1983, there were 27 licensed uranium 

mills located m Colorado, New Mexico, 

South Dakota, Texas, Utah, Wasbmgton. 

and Wyommg. These mills have 

produced a total of over 150 million 

metrtc tons of tailings whtch contain 

radioactive elements from the uranium 

decay cham, mcluding radium·226 which 

decays to radon-222. The latter Is a 

radioactive gas wh1ch Is emitted from 

the piles to the ambtent atr. 

EPA 1ssued standards under the 

Uraruum Mill Tailings Radiation Control 

Act (UMTRCA) (40 CFR Port 192 

Subparts D and E) for the management 

of tailings at' locations that are licensed 

by the Nuclear Regulatory Commission 

(NRC) or the States under Ti tie lJ of tho 

UMTRCA. These standards do not 

specifically limit radon-2ZZ emissions 

until after closure of the facility. When 

the UMTRCA standards were 

promulgated, the Agency stated tho! It 

would 1ssue an ANPR for considerollon 

of control ofradon emtsstons from 

uraruum tailings piles durmg the 

operational pertod of a uraniUm mill. 

ThlS notice fulfills that commitment. 

The Agency tasued Envtronmentol 

Radiation Protection Standards for 

Nuclear Power Operations (4Z FR 2050, 

January 13, 1.977). These standards (40 

CFR Part 190) limit itte totallndivlduol 

radiation dose caused by emtssions 

from facilities that compnse the uranium 

fuel cycle, mcludingJicensed uramum mills. At the time 40 CFR Port 190 was 

promulgated. there eXIsted constderablo 

uncertamty about the public health 

tmpact of eXJsting levels of radon·222 in 

the atmosphere, as well as uncertomly 

about the best method for management 

of new man-made sources of the gos. 

The Agency exempted radon-ZZ2 from 

control under 40 CFR Part 190 since at 

that time the problema associated with 

radon emtss1ons were constderod 

suffictently different from those of othnr 

radioactive mater1als assoc10ted with 

the fuel cycle to warrant separate 

constderation. 

Subsequently, standards were 

proposed under the Clean Atr Act (48 FR 

15076, April 6, 1983) for NRC licensees, 

but uramum fuel cycle facilities, which 

mcluded operating uramwn mllb, wore 
Federal Regtster I Vol. 49, No. 212 I Wednesday, October 31, 1984 I Proposed Rules 43917 

excluded because these sources·are 

subject to EPA's 40 CFR Part 190 

standard that provtded protection 

eqwvalent to that of the Clean AJ.r Act. 

It was noted dunng the comment penod 

for the Clean Alr Act standards that 

radon-222 emitted from operating 

uramum mills and thell' actively used 

tailings piles are not subject to any 

current or proposed EPA standards, and 

that there may be significant nsks 

associated with resulting radon-222 

emiSSIOn. 

The Agency 1s particularly mterested 

m rece1vtng mformation on the followmg 

ISSUeS: 

[1) Radon-222 em1ss1ons from these 

facilities; 

(2) Applicable control options and 

strateg1es, mcluding work practices: 

(3) Feasibility and cost of control 

options and strateg1es; 

(4) Local and reg1onal unpacts due to 

enuss1ons of radon-222 from active 

uraruum mills: 

(5) Methods of determ.JIUDg 

compliance with a work practice type of 

standard: and 

[6) Effect on the mdustry if controls 

are reqUll'ed. 

Daled: Oclober 23. 19M. 

WU!iam D. Ruckelshaus. 

Adnumstrator. 

(FRD:<:.&I-:z;{!lfi!..--;11~Z:14a:::~) 

BIUJHQ CODE G!-C~