43906 

### Federal Regtster 

## f Vol. 49, No. 212 

## I Wednesday, October 31, 1984 

## I Proposed Rules 

# ·==-
ENVIRON M ENTAL PROTECTION AGENCY

40 CFR Part 61 [AD-FRL 2694-2]

**t~~tlonal** Emissi on Standards for Hazardous Air Pollutants; Regulation of Radlonuclldes

AGENCY : 

### Environmental Protection Agency (EPA).

ACTION: 

### Withdrawal ofproposed standards.

SUMMARY: 

### On April6, 1983, the Environmental Protection Agency

, pursuant to section 112 of the Clean A1r Act, proposed standards for sources of em1ss1ons ofradionuclides 

### m four categories: (1) Elemental phosphorus plants; (2) Department ofEnergy (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 ofradionuclide emissions: (1) Coal-fll'ed boilers; (2) the phosphate mdustry ; (3) other extraction mdustnes; (4) uramum fuel cycle facilities, uraruum mill tailings, and management ofhigh- 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 em tsstons from the other five source categones constdered. The U.S. Distnct Court for the Northern Distr1ct ofCalifornia 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 Protect ion 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 ofthe Background Informatibn Document contams a 

### complete descnption ofthe Agency's methodology used m 

### its nsk assessment of the hazards assoc1 ated with mbome emissions ofradionuclides. Volume 2 IS devoted to a detailed descnption ofhow 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 ofcurrent enuss1on control technology, and descnptions and cost estima tes of additional emiSSIOn control technology.

The Agency's written responses to oral and written comments_on the proposed standards have beenplaced m 

### Docket No. A-79-11. Single cop1es ofthe Agency's responses may be obtamed by writing the Program Management Office, Office ofRadiation Programs (ANR

### 458), 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 ofStandards Development

In 

### 1977, Congress amended the Clean All' 

### Act (the Act) to adddress a1rborne enusstons ofradioactive matenals. Before 1977, these em1sstons were either unregulated or were regulated under the Atonuc Energy Act. Section 122 ofthe Actreqwed the AdmiDlstrator ofEPA. after provtding public notice and opportunity for public hearmgs (44 FR 

### 21704, April 

## u. 1979), to deternune whether emiSSions ofradioactive 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 stud ies of the b1olog1cal effects of 1omzmg radiation mdicated that exposure to radionuclides
mcreases the nsk ofhuman 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 entit led "Radiological Impact Caused By EmiSSions oofRadionuclldcs mto 

### Atr m the United States, Prelimmary Report," [EPA 52017-79- 006), Office ofRadiation Programs, 

### U.S. EPA, Washmgton, D.C

., August 1970.

Section 122(c)(2) ofthe Act directed that, after havmglisted radionuclidos us a hazardous a1r pollutant, EPA enter mto an mterag ency 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 ofEnergy 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 p hosphorus plants: (2) DOE facilities: (3) NRclicensed facilities and non-DOE Fodorol facilities: and (4) underground uranium
mmes. Several additional so urce 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 mdust ms: (4)
uramum fuel cycle facilities, uranium mill tailings, and management ofh1gh· level radioactive waste; and (5) low energy accelerators (48 

### FR 15076, Aprll 6, 

### 1983). At the time ofproposal, it 

### was thought that these nme source categones were all that potentially released radionuclides to a1r at levels that could warrant regulat ory 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 ofRadiation 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. 

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## I Wednesday, October 31, 1984 

## I Proposed Rules 

### 43907

requests to extend the time for subiruSston ofpublic 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 ofthe SAB Subcommittee, transcnpts of all public meetings ofthe 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 forFinal Rules."


## m. Summary ofthe F'mnl Actions

.

On April6, 1983, the Agency proposed standards for sources ofelDISSions of radionuclides m four categones: (1) EPA has considered andresponded 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 ofthe proposed standards for elemental phosphorus plants has been completed andplaced m the Docket (Refer to "Regulatory Impact AnalysiS ofEiruss1on Standards lor Elemental Phosphorus Plants," October 1984)•

. The 

### final report on control technology for radionuclide eiruSsions to

rur at Department ofEnergy facilities has beenpublished and a copy 18 available mthe Docket (Refer to "Control Technology for Radioactive Enuss10ns to the Atmosphere at U.S. Department ofEnergy Facilities," [PNL4621], October 1984)

.

In response to requests for Wider sCientific revtew ofthe Agency's nsk assessment, the AdlDlmstrator m December 1983, formed a Subcommittee

onRisk 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 ofthis notice. On the basis of the Subcommittee'sreVIew, the final Background Information Document has beenrewritten to mcorporate recommendations made by the Subcommittee. The reVISed Background Information DoCllment presents an mtegrated nsk assessment followmg the format and methodology suggest ed 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. ForDOE facilitie

. s, the Agency proposed on emissionlimit 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 ofthe Act (Sierra Club v. Ruckelshaus, No. 84-0656 WHO). In August 1984, the Court granted the Sierra Club's summary Judgment motion and orderedEPA to take 

### final action onits 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 currentpractice proVIdes an ample margm ofsafety 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 ofunderground 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 ofusmg bulkheadin.!; and other techniques to controlradon 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 ofproposal 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 thebase orfinal regulation or a proposal1 s not y et 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 ofProposed Rulemakms for Radon-222 Eiruss1ons from Underground Uraruum:Mines to solicit additional mformation on control methods, such as bulkheading and other forms oroperational controls.for radon222 enuss1ons from these mmes. Such an approach could avoid many ofthe techrucal and legal difficulties pose by EPA's proposed standards.

In addition to the four s ource categones forwluch 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 mforma tion dnnng the public commentpenod that convmced it of a need for regulation of any ofthese five cntegones. Therefore. the AdlDlrustrator affirms the ongmal deciSIOn not to regulate these sources, belieV1Dg that adequate publichealth protection

**ex~sts** to satisfy the reqtlll'ements ofthe CleanA1r Act.

When the Agency promulgatedits standards for activC'uramum 

### mill tailings (40 CFR 192. SubpartsD and E), it deeded that the control oftheradon222 elDISSions from the a ctiveuramum mill tailings piles could more appropnatelybe 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 wereprobably the
most practical way lo controlradon enuss1ons at active uraruum

### mills. Consequently

, EPA 

### 1s 1ssumg. Simultaneously 

### with this notice, an Advance Notice ofProposed Rulemaklllg for Radon-222 EmlsSions from Ltcensed Uramum Mills.

## , 43908 

### Federa l Reg1ster 

## I Vol. 49, No. 212 

## I Wednesday, October 31, 1984 

### /

·Proposed Rules

The withdrawal of the proposed standards for elementa l phosphorus plants, Department ofEnergy facilities, Nuclear Regulatory Comrrusston

- licensed facilities and non-DOE Federal facilities, and underground uraruum mmes are final actions

. Also, the dectston not to establish radion uclide emtsston standards for coal-fired boilers: the phosphate mdustry, other extraction mdustnes: uraruum fuel cycle facilities, uraruum mill tailings, and management ofhigh

- levelradioactive waste: and low energy accelera tors are fmal actions.

**Judie~al** 

### revtew 1s available only by flling a petition for rev1 ew m the United States Court ofAppeals for the Distnct ofColumb1a Cir cuit 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 ofcomments were made which apply to all of the source categones constdered and which address the bases ofthe 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 ofEPA'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.



### Res ponses: EPA has concluded that extsting radionuclide enusstons .from
some stationary sources can represent a significant nsk offatal 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 ofpopulations of humans and ammals ex p osed 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 offatal 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 ns k 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 ambt ent concentrations ofradionuclides, on the proxmrity oflarge populations to

, emitting sources, on estima tes ofhealth nsks to exposed populations, and on considerations ofuncertamties assoCiated with rtsk estimates

.

Based on this analysts, EPA has concluded that the presentrecord 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 of500 

### 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 ofGeneral Counsel, that today' • action• are cona tatent 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 1ub stantive concluatons set forth In t oday'a rulem alang I a by dellaling the particular pollutant
m

v .olved. Thouah EPA does not preaently accept that poalijon,lt atand1 ready to amend thta package promptly alonslheae lines ifthe 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 oflimltlng exposure to mdiv1dunJs to 500 

### mrem/y to the whole body and 1500 

### mrem/y to any organprotects 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 ofdevaloplng a fatal cancer of about one In one hundred due to the radiation exposure. In addition

, that same person would face
an approXllllately equallovel ofrisk of nonfatal cancer and ofpassing 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 ofradionuclldes from most facilities

. The Agency oxpoots that 

### tlus current policy will continuo In the future and docsnot 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 ofestablishing an emission limit of zero. The tmplementatlon of such a standard for the sour ca 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 

### ofthe Act.



### Comment: EPA ts required to promulgate standards under all of lts applicable authorities m order to {ultill the mtent ofita Congresstonal mandates. For example, the Agency mustregulate atr emtsstons f rom 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 shouldbe based on cost analyses, and 

### ifnot cost-effective, they should not be promulated. Others felt that costs should notbe considered
at alL



### Response: The Agency believes that g1vmg equal wetght to costs and benefits IS mappropnate m developmg standards under Section 112 ofthe Clean Alr Act. Congress clearly mtended that public healthprotection considerations be pnmary and that cost be secondary.

The Agency did consider, m developmg these rules, the availa bility and practicality ofcontrol eqwpment. While thts was not a pmnary constderation, knowledge of the availability ofcontrol technology lS necessary when makmg Judgments on the need for and level ofeiiDssion standards. EPA believes these considerations are withm the Adm.uustrator's discretion m deteriiDnmg what level ofprotection 1s adequate. The Agency constdered costs to a limited degree consistent with tins overall perspective m reachmg its dectstons on coal-fired boilers and elementalphosphorus 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 ofthe' 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 ofthe 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 ofthe 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 healthts 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 wayto 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 ofthe 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 siteboundary. Because the proposed standards are so restrictive, 

### thls IS either very e"-penst\'e

or altogether Impractical.



### Response: Questions concernmg the Implementations ofstandards for a1rbome radionucllde ermsstons are moot m light ofthe Admmtstrotor's dectston to withdraw the proposed rules.



### Comment: Standards shouldbe 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 andhas 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 proposedrules.

V Techmcal Rev1ew by the SClonco Ad\oisory Board

In response to critiCism that the Agency did not have suffictent outstde re\'Jew ofits methods used to assess nsk due to radionuclides. the Adm.mistrator formed a subcommittee ofthe Agency's SCience Ad\'lsory Board to reVIew the sctentific basts oftheproposed standards for radionuclides. The Subcommittee held three public meeUn:;s: the tll'St on January 16. 1984, the second onFebruary 21-22.1984, and the tinrd onMarch 

### 22. 19i34. At these meetings, the Subcommittee was briefed byAgency staff on the methods used m estimating nsks causedby aJl'bome radionuclides. The panelheardfrom members ofthe public on the Agency's nsk assessments
, as well. The Suocommittee also held executive sess1ons to constder the mformation presentedby the Agency andthe public.

Transcnpts of thepublicmeetings are a\•ailable m the Docket. The Subcommittee's 

### final report, entitled "Report on the SaentificBaSIS 

### ofEPA's Proposed National EmlsS!on Standards for Hazardous

### AlrPollutants for Radionuclides," was transmitted to the Admunstrator on August 17, 1984. A copy oftins report and the Agency's response are available m the Doc.la!t.

In theE.xecutive S1liD.IIllUY ofits report, the Subcommittee noted thatits 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 ofrodionuclides through the enVll'onment from 8ll'bomereleases, m calcul:1Un:; the doses reCC1ved by persons mhalins ormgesting tlus radioactivity and m estimating the potential cancer and genetic nsks ofthe calculated doses? Second. are the mdiVldual facts, calculational operations, SCientific Judgments. and estimates ofuncertamty documented and mtegrated m a clear andlogtcal

manner to pro1l1de a risk assessment that can be used as a sCientificbasiS for nsk managementpurposes, i.e

.. standard·setting? Withregard to the 

### first question. the Subcommittee concluded thatEPA had gathered the appropnate sctentific mformation neededfor a nsk assessment m a techmcally proficient

manner.

The Subcommittee made several technical su:;geslions onhowEPA could Improve its as5llmptions, models, and methods for estimating nsks. Most of these techrucal suggestions havebeen mcorporated tntoEPA's nsk assessment procedures. The nsk assessmeJlt for the final rule reflects these modifications. Some ofthese techrucal suggestions mvolve additonal research to tmptove future nsk assessment methods. Those

### 43910 Federal

**Reg~.ster** 

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## 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 ofregulatory 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 ofradiat ion doses and the assoCiated degree of
uncertamty, to a vanety ofregulatory options from which to choose. Only m th1s way did the Subcommittee f eel 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 p rocesses by its own Sc1ence Advisory Board. EPA does believe that.
on balance, its nsk estimates for specific
sources ofradionuclide 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 f o

r 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 RiskAssessment



### Today's deciSion 1s based on a developmg body of sc1ence and policy

concemmg the treatment of one particula r class ofhazardous 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 o r 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 ofexposure may pose some nsks ofadverse 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 nskper unit ofexposure (or "potency"). The third step 1s to estimate how many people are exposed to the
sources ofradiation, 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 cat egory 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 ofparticu lar 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 ofmax1mum exposure faces an estimated mcreased r1sk ofcancer 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 ofmax1mum concentrations and spend thelfwhole 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 of0.05 

### 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 ofmax1mum 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 ofnsk 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 muc h mk 

### tlto most exposed persons bear. Two
sources ofradionuclide or chem1cnl ellllSS!ons could have s1milar population lDlpacts, but very different maximum mdivtdual nsks, or v1ce versa. Any sanslble "r1 sk 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 

## eslimo tes of

### Federal Regtster 

# I Vol. 49, No. 2.12 

# I Wednesday, October 3.1, 1984 

# I Proposed Rules

nsk from radionuclide e!Dlsstons because ofthe 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 100mrem/y for eachperson. 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 ofProposed 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 ofsafety, as reqwred by section 112 of the Act. Thls alternative lS also appropnate ifimplementation ofthe 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 LevelThat 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 leve ls and still proVlde an ample margm ofsafety. Establishmg the standards atthese levels would also respond to severa l comments regarding consistency among the categones and with the recommendations ofrecogruzed national and mtemational radiation protection groups, and regarding the need for greater operator flexibility m selecting control technology and methods or demonstraUng compliance.


### B. ElementalPhosphorus 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 ofthe proposed rule, the public comments, the Sc1ence AdvJsory Board report. the nsk assessment, and otherpertinent 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 ofthls 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 peryear, or approXImately one case every seventeen years. Thts nskJS sunilar to otherr1sks that EPA has constdered msuffic1ent to warrant Federal regulation m comparable Section 112proceedings. About 80% ofthe 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 ofthe plants, EPA estimates the dose rate to mdivJduals at the location oflugbest all' concentrations to be about 600 mrem/y to the lung. The chance ofgetting cancer from a lifetime of exposure at tlus location ts calculated to be about one m
one thousand. 

### Ifnsk to the "most exposed mdiVIduals" were the only critenonfor 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 ofits proposed standards. That alone would not JUStify a deoston
not to regulate, bulm tlie context ofthe limited aggregate nsk and other factors described earlieritcontributes to such a dectston, particularlygiVen the Scence AdVIsory Board's statutoryrole as the Agency's soence adv1sor.

Over the next severalyears, EPA**\~ill** work with the Scence AdVISory Board to satisfy its concerns regarding the sctentific basts ofregulations 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 curentlyrecoDSidermg its amb1ent 811' quality standardfor particulates, and may shiftits emphasis toward regulating the smaller-siZed particles. Since the two elemental phosphorus plants bemg coDSidered here emit large amounts ofthese smallar particles, they mayreqwre additional controls based on these new standards. Luniting enuss1ons ofthese smaller particulates would also control some of the radionuclide em1Sstons from 

### the plants.



### Z. The area surrounding these two plants 1s charactenzedby lugh total levels ofradiation from a vanety of

sources. The storage and \Vldespread

use ofslag and possibly other waste products from these plants have stgnificantly mcreased the natural background radiation levels m parts of the communities. 

### Inparticular, phosphate slag from these plantsbas been\Vldely used as aggregate 

### inroad and house construction m these areas. EPA and the State ofldaho mtend to perform a total assessement ofthe

vanous sources and will mvestigate ways to reduce orprevent

### 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 ofDOE 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 ofthe CleanAir Act. Therefore, the proposed rule ts withdrawn and the rulemakmg ts termmated.

EPA estimates the total nsk to exposedhuman 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 13years. Th1s nsk 1s comparable to nsks that EPA hascons1dered msufficiertt 

### tn warrantregulation 

### in Similar Section 112 proceedings.

Doseratesfrom the fourDOE facilities withthe 

### greatest radioiii.lclide em1ss1ons range from 50rmem/y to 

### sa mrem/y to thelung; oneofthese facilities deliver.r a doserate 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, somewhatlower thanthe max.unum r1sks elemental phosphorus plants. Once

agam, 

## 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. tolevels that are as Iow as reasonabl y ach1evable. 

### 'flus program 

### a operated by the Department m keepmg \'llith the longstanding.recommendations ofthe National Council onRadiation Protection andMeasurements, the International Comnuss1on on Radiological Protection, and the Federal Radiation Council to av01d radiation, exposure wherepractical. Whi!e the Agency recogruzes that DOE facilities mamtam very large quantities of radionuclides m the1r mventones. at many ofthe1r 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 notto regulate.

As prevtously noted, EPA currently has a Memorandum ofUnderstanding (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 Understandingas appropr1ate.


### D. NuclearReculatory Commission (NRC)-Llcensed Facilities and 

### Non-DOE Federal Facilities

It 1s also the Admm1strator's judgment that the presentrecord does not support
a conclus1on that regulation ofNRClicensed facilities and Federal facilities other than DOE facilities ts necessary to protect thepublichealth with an ample margm of safety, within the meaning of section 112."Therefore, the proposedrule
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 whichregulations were proposed fo be no more 

### than 

## o

. oz fafat cancerper year, or less than one case every 

### fifty years. Tins nsk 1s comparable toother nsks thatEPA 

### has cons1dered msuffic1ent to warrantregulation m sLmilar Section 11Zproceedings.

EPA calcalates the changes of developmg 

### fatal cancer from a lifetime ofexposure to the most concentrated emiss10ns from the NCR facijitiyw:ith the greatest doserate atnamore than two m ten. thousands. EPAbelieves that the NuclearRegulatory ComD1Jss1on and otherFederalfacilities

### will continue to lm.Plement programsto keep exposure of thepublictolevelsthat are aslow as reasonably acluevable. 

### and adeqtiate 

### to protect the public a.g.amst SJgnificant ' adverse effects fromradiation:. Etm3stons should not Significantly

mcrease m the future.EPA 

### willcontinue its ovecnght ofemisSJoas from these facilities, 

### and should

### this change, the Agency will reexamme its deetSJon not to regulate.



### Asprevtously noted EPA currently has a Memorandum ofUnderstanding (MOU) with NRC regardiDg the development and lDlplementation of standards under section U2. EPA mtends to coordinate with NRC to seek to modify theMemorandum of Understanding as appropnate

. 

### E. 

### Undergrounc! Urammum Mines

The Agency proposed a standardfor 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 ofthe foltowmg procedures: (1) Reducmg the precentage oftime the

mme operateg. (2J fncreasm.g the effective hetght ofthe release, and {3) controlling additional land. EPA expected thatnnne operators would most likely 

### tryfo control landwitlun about 2 kilometers ofthe 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 thatradon could not 

### be collected by availablepollution control eqwpment beforebemgreleasedfrom the vents, rednction9 afforded bybetter bulkheading orseaTanfs werelughly uncertain, and reducmg the volume- of atr flow wasnotfeasible due tothe effect on occupational exposure. Comments on theproposed rule mqicated Jhat controlling a sufficient amount ofland m1ght-not be feasible because pnvate owners ofland 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. 

### Itwas. suggested thaf theAgency had used overly conservative assumptions m the dispemon andrlsk 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, andequillbr1um raUos tn the rev1sed nsk assessment. The most recent estimates ofthe lifetime risks to mdividuaJs Iivmg near these mme runge from one m one. thousand to one inone hundred. Thepotential 

### ex.JSts for even. }ugber nsks m some situations, e.g

.. a person livmg very close to s everal honzontal mmes vents or 

### in areas mfluenced by multiple mine emissions

. Lifetime rtsks m these situa tions 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 protectpopu!nlions and mdiVJduals livmg near underground

uraruum mmes.

AnalysLS of thelikely reduction. m health nsJcs afforded by the proposed standards showed that while nsks to neatly mdiVlduala were reducedby a factor of abaut ten, the raoks to the total population were only neg.Ugibly reduced. The lack of populationr1sk redaction ls due 

### to the fact that radon

**~:eleoscs** would notbereduced by theproposed rule, they would only be more wldoly dispersed.

EPA bas concluded tbat 

### its proposed standardwas legally flawed m two ways

. First, becauseitwould not ha.va limited radionuclide enusSlons on a continuous baSts, butwas pnmarily based on the use ofdispersion technology toreduce nsks to nearby people, it did not quall!y an "eiDlSSIOn standard'' withm the meaning ofsection 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 tobevalid, they must alsohave- 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 populationrisk apprectnbly, when such nsk waS' lugh

, iffoiled to

### Federal Register 

## I Vol. 49, No. 212 

## I Wednesday, October 31, 1984 

## I Proposed Rules 

### 43913

meet the public health protection purposes ofthe Act.

Because radon

-222 1s a-noble gas and the volume ofrur discharged through

mme vents 1s very large, the re 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 ofradon-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 rece 1 ved additional techrucal mformation m a 

### report prepared for the U.S. Bureau of Mines, mdicating that work practices, such as bulkheading abandoned sections ofmmes to trap the radon before itIs 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 ofradon-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 diff er 

### m configuration; for example, some mmes have very f ew 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 tendto 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 canbe realized consistently for an appreciable segment ofthe mdustry, and to determme methods ofbulkheading 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

cons 1 dered 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 ofProposed Rulemakmg announcmg tlns dec1s1on IS 

### being published simultaneously with tlnsnotice.


# vm. Fmal Determmation for Sourcos EPA Proposed Not To Regulato

EPA preVIously tdentified several

source categones that emil radionuclides to a1r butproposed 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-FiredBoilers

Large coal-fired boilers 

### are used by utilities and mdustry to generate electricity and to make process steam andhot waterfor 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

anmdiVIduallifetime nsk offatal cancer ofone 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 notto 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 onboth 

### a consideration ofthe level of

### nsk and on
a consideration of total cost and practicality of additional control eqwpmenL Some com.menters stated costs should notbe constdered under section 112 

### ofthe Clean Atr

### Act. EPA beUeves it 

### 1s not reasonable to avotd cons1denng cost and practicality of control technology; however, the protection ofpublic health was the pnmary consideration m reaching tlns deCISIOn.

Some commenters ra.Jsed the question ofwhether 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 NationalLaboratory to mvestigate the existence of such boilers. The Agency was unable to find boilers

_ with radionuclide euuss1on rates Significantly greater thanthe model facility we studied tn 

### detail In 

### fact. the ma)ority ofboilers can 

### be demonstrated to have emiSSIOns much lower.

Some com.menters statedthatthe 

### reqwrements ofthe CleanAir

### Act dictate that EPA must propose an em1ss1on standard specifically for radionuclides, regardless ofother 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 ofsafety 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 onthe 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 rockmmed m 

### the United States. Phosphate deposits contam elevated quantities ofnatural radioactivity. pnnc1pally uraruWJl.23S. 

### and members of its decay 

### sertes. Uraruum concentrations 

### m phosphate deposits range from. ten to one hundred times the concentration ofuraruum m 

### other natural rocks and soils

. Phosphate

**Rocl~** 

### Processing Planls

The processmg ofphosphate rock m 

### dryers, gnnders

, and fertilizer plants results 

### mthe 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 bynew soW'Ce performance standards issued underSection 111 of the Clean A.Jr Act In 

### the caseof fertilizer plants, thenelv source performance standard for finonde 

### also provides for effective controfof particulates. Existing

**dryin~r.** 

### gnnding. and fertilizer plants 

### areregulated 

### for pa.rticulate emiSSions by State Implementat ion pfans as required bythe 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. Thensks fo nearby mdiVlduals and the total population risks due fo radionuclide enusstons from these three types offacilities 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 offatal cancerof 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 forennsSions 

### 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 phosphaterock processmg facilities- and further s tated 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 phosp hate rock processmg facilitias and that co:Jt sliould not be constdered m reacbmg 

### a dectslon on the needfor these standards. Even without cons1detmg 

### costs, EPA 

### doe!! not agree

### that standards areneeded for these: facilities for the reasons JUSt 

### stated.

EPA did notpreVIously 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 whetherstandards were needed. In 

### addition. the Agency conducted emxsswn tests 

### attwo 

### ofthese facilities. EPA has 

### notyet completed

### its analysis ofthese emiSSIOn tests 

### or earned out a nsk assessment for these calcmers. Therefore, no defermmation of the need for standard$for phosphate rock calcmers atwet

### process fertilizer plants IS 

### made at tlus time.



### Afterconsidenng all comments. EPA has deCided 

### to affll'lD and make final its 

### deciSion notto regulate radionuclide enusstons tram phosphaterock proces.smgplants. otherthau phosphate rock calcmers atwet process.fertilizer plants. A deCISIOn regarding the need for standardsfor 

### this 

### latter source \•Jill 

### be made after completion ofthe

**Agency·~** 

### analys8$ ofenuss1ons and

### nst-.s from these facilities. PhosphogypsumPiies.

Several comments were received requestingEPA 

### to iSsue stanclartbt

### under the Clean Alr Act 

### for radionnclide emiss1ons from phospbogypsum piles (fertilizer plantwastematenalt. EPA did 

### notpropose radionuclide standards for 

### t1ns sourcebecause it 

### believed thatsuch wastes wouldbe more appropnately regulatedunder the Resource Conservation and Recovery Act 

### (Pub. L. 94-580).



### After coDSidenng 

### all

**commen~** 

### EPA
lS 

### reevaluating the needforradionuclide standardsfor tius

**sourc~** 

### Prelirmnary nsk estimates mdicate 

### that 1npj.qidual lifetime nsks 

### from exposure:tomr

**em~ss1ons** from. 

### these piles may be as lugh 

### as ezght 

### m ten thousand. Population nsks may be OII

### theorder of

**on~**

### fatal
cancerper year. The.A.,<18ncy will continue its 

### exannnation ofthe need for
a

**standardforthr~somce** 

### category. C. OtflerExtraction Industries



### Almost all mdustnal operations mvolvmgremoval andprocessmg of soU:t androcks to recover mmeral
resources release some radionuclides mto the atr. EPAhas conducted studies ofa1rbomeradioactive 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 greatestpotential for rur 

### eml!ISIOno ofradionuclides.



### 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 rangefrom 0.000001 

### to 0.01 

### fatal cancerper year.

Most ofthe comments rece1ved 

### wore from mdustry representativctJ who concurred with EPA"s proposal not to regulate these facilities. In thetropmlon, enuss10ns, doses, amfrisks were so small ibat 

### a regulation was unnecessary. No ne\17 mfonnation wasprovided to tho Agency dunng the public comment penod wlnen mdicatecf a 

### need for standards. Additional Agency studios have confirmed thatradlonuclida 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-LevelRadioactive Waste



### The uramum fuel cycle consists of operations associated wilh production ofconunere1ai electricpower by 

### IIebl water reactors

**usm~**

### uran1um fuel. It mcludes nuclear power plants 

### and facilities that mill uranium ore. procen uranium. 

### andfabricate and reprocess urantum fuel. EPA haa promulgated em1ss1on standards for normal operations o£theuranium fuel cycla under the Atomic Energy Act (40 CFR 

### Part 190}

. These s tandards 

### 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 ofprotection whtch

**~**

### Federal Regtster 

## I Vol. 49, No. 212 

## I Wednesday, October 31, 1984 

## I Proposed Rules 43915

satisfies the reqwrements ofthe Clean 

### .Alr Act. An ennssion standard promulgated under the Clean AirAct 

### 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 ofthese tailings eXIst at both mactive and active uramum 

### mill sites, locatedmostly m the WesL The high concentration ofradium-226

- m the tailings can-result m sigDificant emiSSion

orradon-222, a radioactive gas. Under current EPA disposal standards which reqwre long term stabilization ofthe tailings piles, 95% or more ofthe 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 ofpublic health pJOteclion comparan1e to an 811' emission standard.

However, commenters noted that randon 

### emiSSIOns from the 

### tailings piles at licensed uramwnmills are exempted from the reqwrements of40 CFRPart 190. They are controlled, mstead. by NRC regulations which allow 

### a concentration ofSpCi/1 ofradon-222 m unrestncted areas. 

### Tlus value represents

a level of

### nskthatmaybe sigllificant. EPA lS publishmg, sunultaneously with this notice, and Advance Notice of ·Proposed Rulemakmg to considerthe need

### for an emlSSlon standard

### forradon emisSion fromlicensednramwn mills.

Highly radioactive liqmd or solid
wastes from reprocessmg spent nuclear fuel, or the spent fuel elements**the~nselves** 

### ifthey 

### are disposed of withoutreprocessmg, are conSidered high-level radioactive waste. EPA has proposed standardsl.Ulder the Atomic Energy Act to limit public exposure to the radionuClides m 

### t1us :waste pnor to disposal andhasproposed that operations be conducted to reduce exposures below the standard to the extentreasonably achievable. The Agency expects 

### its standardsfor the management ofhigh-level raaioactive waste to be promulgated m the near future. These standards

### will control eolissions durmg the operationalphase ofthe disposal site to a levelwhich results m a dose eqwvalent no greater than 25

### mrem/y to the whole body orto any organ. except the thyrOid. which may receive a dose as lugh as 75 mrem/ 

### y. Th

. ese standards 

### will proVIde a level ofpublichealth protection comparable
to an emiSston standard 1ssuedunder 

### the Clean Air

### Act After consideration ofall 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 ofhigh-level radioactive waste.

E. Low 

### EnergyAccelerators

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, andradiation 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 extremelylow. 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 ofthe beanngs, all written statements, the Agency's responses to comments, and otherrelevant documents have beenplaced m the -docket and 

### are available.for mspectlon and COPYin& durmg normal workmg hours.

Dated: October 23, 1984. \Wliam D. Ruckelsbnus, 

### Admuustratcr.

[FR Doc. &WMSar.!cd lo-:G-&&: Z:UPI
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: EnvironmentalProtection Asency (EPA).
ACTJON: Advance notice ofproposed rulema.lang.

SUMMARY: This notice anD.OtlllCCS the Agency's mtent. under Section 11.2 of the CleanAirAct, 

### as amended. to start 

### a program to constder a standardbased

onbulkheadins 

### orrelated techmques to control radon ennssions from underground 

### -uranium min

. es.

### This st3lldard could

### be an emission standard.

or a design, equipment, workpractice. 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 ormaximum value.
ADDRESS: Comments must be submitted (in dupUcate, 

### ifpossible) 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. EnVIronmentalProtection Agency, 

### Washington. D.C. 20460.**SUPP~ENTARYINFORMAnON:This** Ad\'ance Notice ofProposed Rulemakms (ANPR) serves to 

### mform mterestedparties that the Agency

### is constdenns 

### a rulemakmg related to the deSI:;n and 

### type ofeqmpment. 

### work practices, operationalprocedures. orto emiSSion standards based on these techruques, to control the radon-222 emisSions 

### from underground uranimn

mmes. 

### As of January 1933, there 

### were 139 orthese mmes located m Arizona, Colorado, New Mexico

. Utah. and Wyommg.These mmes have 

### a productionrate of 6,200 tons of**~Oa** and account for about46% of the total production ofU3

### 0 8 m the United States.

The Agency proposed 

### a standard under section 112 orthe CleanAirAct 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 offatal cancer to nearby mdivtduals ranges from one m
one thousand to one m one hundred. The potent ial 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 ofthts method to the removal ofradon-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 ofradon-222 without controls and with controls, such as bulkheadlng, sealants, mJDe pressuriZation, and backfilling;

(4) Effectiveness, feasibility and costs ofcontrols;

(5) Methods ofdetermmmg compliance with destgn, eqwpment, work practice, or operational type standaros;

(6) Estimates oftmpacts on nearby mdlv1duals and populations due to radon-222 em1ss1ons before and after control:

(7) Extent ofradon-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 ofproposed 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 ofmaxtmwn value.
ADDRESS: Comments must be submitted (in duplicate, 

### ifpossible) 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 ofRadiation Programs, Envtronmental Protection Agency, Washmgton, D.C. 20460.
SUPPLEMENTARY INFORMATION: This Advance Notice ofProposed 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 ofJanuary 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 ofover 150 million metrtc tons oftailings 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 1 92 Subparts D and E) for the management oftailings 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 ofcontrol 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 ofthe 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 ofothnr 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 ofthe Clean 

### AJ.rAct. 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 ofcontrol options and strateg1es;

(4) Local and reg1onal unpacts due to enuss1ons ofradon-222 from active

uraruum mills: 

### (5) Methods ofdeterm.JIUDg compliance with a workpractice type of standard: and

[6) Effect on the mdustry 

### ifcontrols

are reqUll'ed.

Daled: Oclober23. 19M. WU!iam D. Ruckelshaus. 

### Adnumstrator.

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

**G!-C~**