EPA 402-R-l 6-004
National Emission Standards for
Hazardous Air Pollutants (NESHAPs) for
Radionuclides
National Emission Standards for Radon
from Operating Mill Tailings
40 CFR Part 61, Subpart W
Background Information for Final Rule
Summary of Public Comments and Responses
December 2016
Office of Radiation and Indoor Air
U.S. Environmental Protection Agency
Washington, D.C.
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U.S. Environmental Protection Agency EPA 402-R-l 6-004
Office of Radiation and Indoor Air NESHAPS Subpart W Response to Comments
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Final
December 2016
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EPA 402-R-l 6-004
NESHAPS Subpart WResponse to Comments
ntents
Introduction i
What is Subpart W? i
Public Comments i
Section 1 - Legal Authority to Promulgate Subpart W Regulations 1
Issue 1: Major source threshold for radionuclide emissions 2
Issue 2: Listing the facilities regulated by Subpart W as a source category or subcategory 2
Issue 3: Adoption of emissions standards instead of management practices 3
Issue 4: Regulation of evaporation ponds at uranium recovery facilities, specifically ponds
associated with in-situ leach operations 4
Issue 5: Inclusion of groundwater protection requirements 4
Issue 6: The scope of activity regulated by Subpart W 5
Issue 7: EPA's authority relative to the Nuclear Regulatory Commission (NRC) 6
Issue 8: The definition of uranium byproduct material in Subpart W relative to the Atomic
Energy Act and NRC regulations 7
Issue 9: EPA's authority to regulate radon emissions from uranium processing facilities 7
Issue 10: Public opportunity to comment on construction of tailings impoundments 8
Section 2 - Definition of Uranium Byproduct Material 9
Issue 1: Suggestion that EPA distinguish between "tailings" and "byproduct material" for its
CAA authority 10
Issue 2: Consistency between EPA's CAA definition of byproduct material and the AEA/NRC
definition 10
Issue 3: Regulation of treated water if it does not contain byproduct material 11
Issue 4: Clarification regarding whether liquids are byproduct material or contain byproduct
material 11
Section 3 - GACT vs. MACT 12
Issue 1: Request that EPA define major and area sources and opinion that CAA 112(d)
requires MACT for sources not so defined 13
Issue 2: Justification for using MACT instead of stronger MACT 13
Issue 3: Requirement under CAA 112(h) for an emission standard unless not feasible 13
Issue 4: Appropriateness of typical mass-based definition of major source for uranium
byproduct material impoundments 14
Issue 5: Data supporting EPA's justification for GACT as effective at newer impoundments 14
Issue 6: Treatment of liquid effluents to remove radium 15
Final
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U.S. Environmental Protection Agency
Office of Radiation and Indoor Air
EPA 402-R-l 6-004
NESHAPS Subpart WResponse to Comments
Issue 7: Extreme weather events 16
Section 4 - Considering All Radionuclides Emitted at Uranium Recovery Facilities 17
Issue 1: Evaluating and considering all HAPs, including Th-232 decay products 18
Issue 2: Evaluating and considering all sources of radionuclides at uranium recovery facilities
19
Issue 3: Evaluating alternative monitoring methods 19
Section 5 - Eliminating the Distinction with Existing Impoundments 21
Issue 1: Grandfathering non-conventional impoundments that are already approved 22
Issue 2: Monitoring and emissions standard for existing impoundments 22
Issue 3: Monitoring and limits for non-conventional impoundments 22
Issue 4: Scope of Subpart W with respect to non-conventional impoundments 23
Issue 5: Monitoring conventional impoundments 24
Issue 6: Restriction on switching of conventional and non-conventional impoundments 24
Issue 7: Clarification of references to construction requirements 25
Issue 8: Level of emission standard based upon current control technologies and data 26
Issue 9: Violations of the current standard and practices 26
Section 6 - Evaporation Pond Issues 28
Issue 1: Proposal to retain one meter of liquid in non-conventional impoundments 29
Issue 2: Reliability of measurement methods for liquid levels 29
Issue 3: Clarifying the term "continuous" as it relates to liquid levels 30
Issue 4: Limiting the size and number of non-conventional impoundments 30
Issue 5: Regulation of treated water if it does not contain byproduct material 30
Issue 6: Clarify the amount of radon reduction from liquid cover 31
Issue 7: Use of liquid cover to limit radon emissions instead of monitoring 32
Issue 8: Clarification of the purpose of non-conventional impoundments 33
Issue 9: Request that EPA consider the entire life cycle of non-conventional impoundments up
to removal 33
Issue 10: Construction authorization renewals 34
Issue 11: Evaporation ponds on top of tailings 34
Issue 12: Evidence or justification for EPA's proposal 35
Section 7 - Limits on Allowable Impoundments 36
Issue 1: Limiting the total number of disposal cells allowed at a facility 37
Issue 2: Limiting the size of impoundments 37
Final
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U.S. Environmental Protection Agency
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EPA 402-R-l 6-004
NESHAPS Subpart WResponse to Comments
Issue 3: Counting and approval of liquid impoundments 38
Issue 4: Risk of spills or leaks from larger liquid impoundments 38
Issue 5: Limiting the total number of operating impoundments 38
Issue 6: Approval of new impoundments relative to closure of existing impoundments 39
Section 8 - Regulation of Heap Leach Piles 40
Issue 1: Regulating heaps under the CAA during the leaching process 41
Issue 2: EPA's proposed GACT for heap leach piles 41
Issue 3: Adequacy and accuracy of EPA's technical information on the heap leach process .. 42
Issue 4: Suggestions for EPA's final rule related to heap leaching 44
Section 9 - Definition of Operation/Closure 45
Issue 1: Extending "operation" through completion of final closure and installation of final
cover 46
Issue 2: Expanding the definition of "operation" to address all phases of operation that
generate radon 46
Issue 3: Implications for regulatory oversight of EPA's proposed definition 47
Issue 4: Including an approved closure plan and milestones in the facility license 48
Issue 5: Applicability of Subpart W to new impoundments at "closed" sites 48
Issue 6: Operations as it involves placement of tailings from process operations, or use for
evaporative or holding purposes 49
Issue 7: Implications of existing and proposed definitions 49
Issue 8: Extending operations through final closure as it affects actual facility operations 51
Section 10 - Eliminating "As Determined by the Nuclear Regulatory Commission" 52
Issue 1: Potential for EPA's proposal to create dual regulation 53
Issue 2: Record-keeping and reporting requirements 54
Section 11 - Cost and Economic Impact Analysis Issues 55
Issue 1: General cost and economic comments 56
Issue 2: Costs related to water use 57
Issue 3: Costs associated with impoundment design and construction 57
Issue 4: Environmental cost of not monitoring emissions 58
Issue 5: Adequacy of EPA's cost analysis of GACT 59
Section 12 - General Comments 61
Issue 1: EPA's rulemaking process 62
Issue 2: EPA's Tribal obligations 63
Final
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U.S. Environmental Protection Agency
Office of Radiation and Indoor Air
EPA 402-R-l 6-004
NESHAPS Subpart WResponse to Comments
Issue 3: Data to support the proposed rule 65
Issue 4: Strength of the proposed rule 66
Issue 5: EPA's risk assessment 67
Issue 6: Justification for EPA's rulemaking 70
Issue 7: Technical corrections and suggestions 70
Section 13 - Out of the Scope of the Rulemaking 72
Issue 1: Enforcement 73
Issue 2: Contamination 73
Issue 3: Cotter 74
Issue 4: Monitoring 74
Issue 5: Miscellaneous 74
Appendix A: Index of Commenters I
Appendix B: List of Acronyms and Abbreviations IV
Final December 2016
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U.S. Environmental Protection Agency
Office of Radiation and Indoor Air
EPA 402-R-l 6-004
NESHAPS Subpart WResponse to Comments
Introduction
This document contains a summary of and responses to public comments on the EPA's
rulemaking to revise the "National Emission Standards for Radon Emissions from Operating
Mill Tailings," 40 CFR part 61, subpart W, referred to throughout as "Subpart W." Subpart W
was promulgated in 1986 under the EPA's Clean Air Act authority to establish National
Emission Standards for Hazardous Air Pollutants (NESHAPs). 51 FR 34056 (September 24,
2986). Following a voluntary remand, the EPA re-promulgated Subpart W on December 15,
1989. 54 FR 51654.
This rulemaking was undertaken as part of a settlement agreement with the Colorado Citizens
Against Toxic Waste (CCAT) and Rocky Mountain Clean Air Action. These groups notified the
EPA of an intent to sue based on the EPA's failure to timely review, and if appropriate revise,
Subpart W as required by § 112(q)(l) of the Clean Air Act. This section was part of the Clean
Air Act Amendments of 1990 and requires the EPA to undertake a review of pre-Amendments
standards within ten years. Upon completion of the review, if the EPA finds revision to be
appropriate, the standard is to be revised to comply with the requirements of § 112(d).
The EPA determined that revisions to Subpart W are appropriate. The EPA proposed revisions
on May 2, 2014. 79 FR 25388. Consistent with the authority provided to the Administrator under
CAA § 112(d), the proposed and final standards incorporate Generally Available Control
Technology (GACT) management practices. See the preamble to the final rule for more detail.
What is Subpart W?
Subpart W provides standards to limit emissions of radon-222 ("radon") from uranium byproduct
material or tailings, which are the wastes resulting from the extraction or concentration of
uranium from any ore processed primarily for its source material content. Radon is a naturally-
occurring radioactive gas that results from the decay of uranium and can cause lung cancer if
inhaled. It is considered a hazardous air pollutant (HAP) under the Clean Air Act. The EPA
determined that radon is the HAP of most significance associated with uranium byproduct
material or tailings.
Uranium recovery facilities subject to Subpart W are licensed by the Nuclear Regulatory
Commission (NRC) or NRC Agreement States under the Atomic Energy Act. Uranium recovery
facilities addressed in Subpart W include conventional mills, in-situ leach (ISL) facilities, and
heap leach facilities. Structures at these facilities that may contain uranium byproduct material or
tailings include conventional impoundments, non-conventional (liquid) impoundments, and heap
leach piles. Subpart W does not apply to these structures once they formally enter the closure
process.
Public Comments
The EPA's proposed rule was published with a 90-day public comment period. In response to
multiple requests, the EPA extended the comment period by 90 days, until October 29, 2014.
The EPA also held two public hearings on September 4 and 5, 2014.
Final
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U.S. Environmental Protection Agency
Office of Radiation and Indoor Air
EPA 402-R-l 6-004
NESHAPS Subpart WResponse to Comments
The EPA received approximately 45 separate sets of comments on the proposed rule, including
multiple submittals by the same author(s). The comments range in size from one page to several
hundred pages, and in many cases contain dozens of individual comments. All told the EPA
identified over 4,000 individual comments. A mass mailer that contains over one thousand
signatures is also in the docket for this rulemaking (Docket No. EPA-HQ-OAR-2008-0218). The
docket also includes the transcripts of the two public hearings held in Denver, CO on September
4 and 5, 2014. All of the comments received are in the docket for this rulemaking. All comments
can be accessed electronically through the Federal Document Management System (FDMS),
available at httv./fwww.regulations.gov. This website provides instructions on how to access the
electronic docket. Some submittals may be duplicated in FDMS, as a commenter may have used
several methods to ensure the comments were received, such as statement at a public hearing,
fax, e-mail, U.S. mail, or directly through FDMS.
This document summarizes comments received on the proposed rule, broken out by topical area.
Full responses to the most significant comments are contained in the preamble to the final rule,
and are referenced in this document. Additional responses are provided in this document. All
comments, whether written or oral, were given the same consideration.
Each section of this document includes a list of issues addressed in that section. Many comments
touched on different topical areas, or on different issues within a topical area. Cross-references
have been provided where possible, but readers are encouraged to consider this document as a
whole, for it collectively reflects the EPA's consideration of public comments. Commenters are
identified by number, which correlates to the listing found in Appendix A and to the submittals
in the docket, where readers can find the full text of comments. Appendix B provides a list of
acronyms and abbreviations.
Final
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EPA 402-R-l 6-004
NESHAPS Subpart WResponse to Comments
Section 1 - Legal Authority part W Regulations
Section 1 - Legal Authority to Promulgate Subpart W Regulations 1
Issue 1: Major source threshold for radionuclide emissions 2
Issue 2: Listing the facilities regulated by Subpart W as a source category or subcategory 2
Issue 3: Adoption of emissions standards instead of management practices 3
Issue 4: Regulation of evaporation ponds at uranium recovery facilities, specifically ponds
associated with in-situ leach operations 4
Issue 5: Inclusion of groundwater protection requirements 4
Issue 6: The scope of activity regulated by Subpart W 5
Issue 7: EPA's authority relative to the Nuclear Regulatory Commission (NRC) 6
Issue 8: The definition of uranium byproduct material in Subpart W relative to the Atomic
Energy Act and NRC regulations 7
Issue 9: EPA's authority to regulate radon emissions from uranium processing facilities 7
Issue 10: Public opportunity to comment on construction of tailings impoundments 8
Final
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U.S. Environmental Protection Agency
Office of Radiation and Indoor Air
EPA 402-R-l 6-004
NESHAPS Subpart WResponse to Comments
Issue 1: Major source threshold for radionuclide emissions
Summary of Comments Under Issue 1:
Commenter 0153 argued that uranium recovery operations should be considered, by definition,
major sources of hazardous air pollutants and should be subject to major source requirements.
Commenter 0153 further stated that the EPA's document "Background Information for Proposed
Area Source Standards" (EPA-HQ-OAR-2008-0218-0001, 0002) is misleading because it uses
the standard major source threshold at Clean Air Act (CAA) §112 (a)(1), that any stationary
source that emits or has the potential to emit 10 tons per year (tpy) or more of any single
hazardous air pollutant (HAP) or 25 tpy or more of any combination of HAP, to support its
conclusion that uranium recovery facilities regulated under Subpart W are area sources. The
commenter stated that radon is not measured in tpy and that the CAA § 112 threshold of 10 or 25
tpy was not intended to apply to radon or other radionuclides.
Response to Issue 1:
See Section IV.A.2 of the preamble to the final rule for responses to this issue.
Issue 2: Listing the facilities regulated by Subpart W as a source category or subcategory
Summary of Comments Under Issue 2:
Commenters 0155 and 0168 stated that the EPA must establish a source category pursuant to
CAA § 112(c)(1) before promulgating CAA § 112(d) standards. Commenter 0155 cites to a 2007
EPA rulemaking which stated that listing pursuant to section 112(c) is a critical aspect and a
condition precedent to issuing CAA § 112(d)(5) standards. Commenters also argued that the
EPA must determine all HAPS present at uranium recovery facilities before the EPA can
establish a source category, develop criteria to differentiate between major and area sources of
radionuclides, and promulgate emission standards, whether MACT or GACT.
Commenter 0153 asserted that because CAA § 112(q) requires pre-1990 regulations to be
reviewed and, if appropriate, revised in accordance with the requirements of subjection (d), the
revision must comply with all applicable requirements in CAA § 112, including all parts of CAA
§112 enacted as part of the 1990 CAA Amendments.
Commenter 0155 also argued that the EPA must establish a source category or subcategory
before promulgating standards under CAA § 112(d)(5) for facilities licensed to manage uranium
byproduct materials. The comments state that the EPA has not complied with the requirements of
CAA § 112 and has not taken the requisite preliminary actions and evaluations to support
establishing revised standards for uranium recovery facilities, specifically GACT. Commenter
0153 stated that the EPA has no basis for setting GACT standards in lieu of MACT standards.
Response to Issue 2:
See Section IV.A.2 of the preamble to the final rule for responses to this issue.
Final
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U.S. Environmental Protection Agency
Office of Radiation and Indoor Air
EPA 402-R-l 6-004
NESHAPS Subpart WResponse to Comments
Issue 3: Adoption of emissions standards instead of management practices
Summary of Comments Under Issue 3:
Several commenters argued that the EPA improperly proposed to promulgate design and work
practice standards in lieu of emissions standards. Specifically, Commenters 0153, 0155, 0172.3
and 0187 stated that the EPA cannot promulgate design and work practice standards without the
Administrator first making a finding pursuant to CAA § 112(h) that emission standards are not
feasible. Commenter 0153 took the position that the EPA has not and cannot make a finding
pursuant to CAA § 112(h) that radon emissions standards are not feasible at uranium recovery
facilities. Commenters 0153 and 0155 assert that the EPA has not and cannot make the "not
feasible" showing, so the EPA must promulgate an emissions standard.
Commenter 0153 stated that the EPA has no legal basis for the promulgation of a design,
equipment, work practice, or operational standard, or combination thereof, in lieu of a radon
emission standard, because design, equipment, work practice, or operational standards are meant
to supplement, not replace, a standard that places specific numerical limitations on HAP
emissions. Commenter 0153 also asserts that the EPA has no legal basis for eliminating the
emission standard for existing mill tailings impoundments.
Commenter 0155 pointed to text from the legislative history of the 1990 Clean Air Act
Amendments and stated that work practice standards must achieve the same or greater level of
emissions reduction as a numerical emission standard. Commenter 0155 argues that radon
emissions will be higher under the GACT standards than they would be under a numerical
emission standard and therefore EPA should promulgate an emission standard.
Commenter 0187 argues that, since the 1977 Clean Air Act (Public Law 95-95) contained similar
language in § 112(e), "it appears that the 1989 design and work practice standards for 'new'
impoundments were promulgated contrary to" the statute because the rule did not contain a
finding that an emission standard was infeasible for new impoundments. The commenter notes
that the Agency made a finding that emission standards were not feasible in the 1986
rulemaking; however, the commenter finds that, by establishing an emission standard for
"existing" impoundments in the 1989 rulemaking, it was not permissible for the EPA not to do
so for "new" impoundments without a corresponding infeasibility finding.
Response to Issue 3:
See Section IV.A.2 of the preamble to the final rule for responses to this issue.
The issues raised by Commenter 0187 regarding the 1989 rulemaking have no bearing on this
rulemaking. Our review of Subpart W is being conducted under the authority of CAA section
112(q)(l), which requires us to revise Subpart W, as appropriate, to comply with the provisions
of section 112(d). This final rule sets standards pursuant to section 112(d)(5), which is applicable
to area sources and does not require a finding of feasibility related to emission standards.
Further, section 112(q)(l) states that standards in effect before the 1990 CAAA "shall remain in
force and effect.. .unless modified as provided in this section." The flaws perceived by the
commenter notwithstanding, the 1989 rule is no longer subject to challenge on these grounds.
Final
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U.S. Environmental Protection Agency
Office of Radiation and Indoor Air
EPA 402-R-l 6-004
NESHAPS Subpart WResponse to Comments
Issue 4: Regulation of evaporation ponds at uranium recovery facilities, specifically
ponds associated with in-situ leach operations
Summary of Comments Under Issue 4:
Numerous commenters challenged the EPA's authority to regulate impoundments associated
with in-situ leach facilities, referred to as non-conventional impoundments in the Subpart W
rulemaking. Commenter 0162 submits that Subpart W does not apply to evaporation ponds at
currently operating and future operating uranium recovery facilities, specifically in-situ facilities
because of the significant amount of process or waste water present. Commenters 0162 and 0169
explain that evaporation ponds should not be regulated in Subpart W because the liquid cover
substantially eliminates radon emissions. Commenter 0169 further supports excluding
evaporation ponds because the original 1989 rulemaking stated that science did not support the
EPA exercising jurisdiction over fluid retention impoundments.
Commenter 0169 similarly argues that the EPA has no legal or regulatory bases to apply 40 CFR
Part 61, Subpart W to evaporation ponds at uranium recovery facilities. Further, Commenter
0169 states that after 20 years of consistent interpretation that Subpart W is only applicable to
uranium mill tailings impoundments, the EPA is now asserting that Subpart W applies to
evaporation ponds at in-situ recovery and conventional mill tailings facilities. Commenter 0169
argues that the EPA's position is inconsistent with the language and the rulemaking history
associated with Subpart W since the regulations discuss uranium mill tailings "piles" and the
rulemaking record states that the radon cover requirements in Subpart W's work practice
standards are not intended to apply to such fluid retention impoundments.
Commenter 0169 challenges that evaporation ponds are not covered by Subpart W because the
specific examples in the regulations do not include evaporation ponds.
Commenter 0173.9 argues that the water impoundments should not be regulated as tailings
impoundments and should not be subject to 40 CFR part 192.
Alternatively, Commenter 0167 supported the EPA's confirmation that in-situ leach facilities are
subject to the EPA's CAA NESHAP jurisdiction. The commenter also stated that where the rule
does not include emissions limits confirmed by monitoring and reporting requirements, the EPA
has not carried out its Clean Air Act duty to minimize or eliminate radon emissions.
Response to Issue 4:
See Section IV.A.2 of the preamble to the final rule for responses to this issue.
Issue 5: Inclusion, of groundwater protection, requirements
Summary of Issue 5 Comments:
Commenters 0159 and 0162 both commented that they do not believe that the EPA has the legal
authority to regulate fluid retention impoundments at uranium recovery facilities. Commenters
0159 and 0162 both questioned the appropriateness of including groundwater protection
requirements in a NESHAP promulgated under the Clean Air Act since they do not affect air
Final
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U.S. Environmental Protection Agency
Office of Radiation and Indoor Air
EPA 402-R-l 6-004
NESHAPS Subpart WResponse to Comments
pollution. Further, Commenter 0162 added that the rule is unnecessary because it is designed to
regulate HAPs yet it incorporates groundwater protection standards. The commenters stated that
the additional requirements for fluid retention impoundments imposed by the imposition of 40
CFR 192.32(a)(1) and, by extension 40 CFR 264.221(c), are not justified.
Commenters 0159 and 0162 both asserted that if the NRC believed that the imposition of the part
192 requirements were justified, NRC would have explicitly referenced 40 CFR 192.32(a)(1) and
by extension 40 CFR 264.221(c) in 10 CFR 40 Appendix A, but it does not.
Alternatively, Commenter 0143 asserted that the EPA cannot allow a situation where the
reduction of radon emissions comes at the expense of increased pollution of the groundwater or
surface water. The commenter is concerned that the rule works at cross-purpose with 40 CFR
part 192.
Response to Issue 5:
See Section IV.A.2 of the preamble to the final rule for responses to this issue.
Issue 6: 'Hie scope of activity regulated by Subpart W
Summary of Comments Under Issue 6:
Commenters 0153 and 0186 concurred with the EPA's authority under Section 112 of the Clean
Air Act to regulate radionuclide emissions at holding or evaporation ponds at conventional mills,
at in-situ leach facilities and at heap leach facilities. However, the commenters contend that the
EPA should not only regulate uranium mill tailings, liquid effluent ponds, and heap leach piles,
because large amounts of radon is also emitted from wellfields and other parts of in situ leach
operations. Commenter 0153 used the Smith Ranch-Highland operation in Wyoming as an
example.
Commenters 0153, 0186 and 0188 also advocated for the EPA expanding the scope of operations
covered by Subpart W at heap leach facilities. Specifically, the commenters encourage the EPA
to regulate radon emissions from the time ore is placed on the pile, to the placement of a final
radon barrier, including periods of standby, and time periods prior to and during the placement of
lixiviant on a heap leach pile. The commenters also take the position that heap leach piles that
are drying out should be subject to a radon emission standard.
Commenter 0154/0170 believes our CAA authority for Subpart W derives from Section 275(e)
of the AEA, and concludes that "EPA's jurisdiction under the Clean Air Act is therefore limited
to 1 le.(2) byproduct material as defined in the AEA." Commenter 0186 disagrees and states that
"the AEA does not limit the authority of the CAA over other radionuclide sources (including
radon emission sources) that may or may not fall under the authority of the AEA. Just because
[Section 275(e) of] the AEA does not limit the CAA jurisdiction over 1 le.(2) byproduct material,
it does not follow that the AEA limits the CAA jurisdiction to just 1 le.(2) byproduct material."
Response to Issue 6:
See Section IV.A.2 of the preamble to the final rule for responses to this issue.
Final
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EPA 402-R-l 6-004
NESHAPS Subpart WResponse to Comments
We agree with the more expansive reading of AEA Section 275(e). That section recognizes the
EPA's existing CAA authority and does not limit it to 1 le.(2) byproduct material. Further, that
section does not address CAA jurisdiction over other materials or facilities regulated under the
AEA.
Issue . authority relative to the Nuclear Regulatory Commission (NRC)
Summary of Comments Under Issue 7:
Commenters 0114, 0159, 0162 and 0172.5 stated that the NRC has exclusive jurisdiction over
the radiological and non-radiological aspects of uranium mill operations and the nuclear energy
business and that the EPA lacks jurisdiction, particularly once the NRC promulgates conforming
regulations. Commenters 0159 and 0162 question the need to retain Subpart W at all.
Commenter 0173.13 contends that the existence of the AEA makes Subpart W redundant and not
necessary.
Commenter 0169 takes the position that the EPA does not have authority to define when uranium
recovery facilities are considered to be "active" or involved in "operations." Instead, Commenter
0169 states that NRC, not the EPA, has authority over decommissioning and decontamination of
AEA-licensed source material recovery facilities, including the mill itself, site soil cleanup, final
tailings stabilization, and groundwater restoration or corrective action. Further, Commenter 0169
states it is inefficient for uranium recovery operations to obtain two separate authorizations with
essentially the same requirements for radon risk from fluid retention impoundments {i.e., NRC
operating license or license amendment and the EPA Subpart W construction approval), and that
these duplicative requirements are inconsistent with EPA's past efforts towards regulatory
efficiency evidenced by the rescissions of Subparts I and T.
Commenter 0114 states the Department of Energy also has authority to regulate this industry.
Alternatively, Commenters 0173.3 and 0172.8 supported the EPA's authority under the Clean
Air Act to regulate HAPs, particularly radon, from uranium processing and do not believe that
the Clean Air Act limits the EPA's regulatory authority with respect to 1 le.(2) byproduct
material at uranium recovery mill operations. Similarly, Commenter 0166 supported the
proposed clarification to 40 CFR § 61.252(b) that the EPA, and not the NRC, is the regulatory
agency administering the radon NESHAP requirements.
Response to Issue 7:
See Section IV.A.2 of the preamble to the final rule for responses to this issue.
Final
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U.S. Environmental Protection Agency
Office of Radiation and Indoor Air
EPA 402-R-l 6-004
NESHAPS Subpart WResponse to Comments
Issue 8: The definition of uranium byproduct material in Sub] relative to the
Atomic Energy Act and NRC regulations
Summary of Comments Under Issue 8:
Commenters 0169 and 0172.5 stated that the NRC, not the EPA has exclusive authority over the
definition of 1 le.(2) byproduct material, as well as the material itself. Commenters 0154, 0169
and 0170 question the EPA's authority to promulgate a new definition for "1 le.(2) byproduct
material" or to equate the definition to the term "mill tailings." Commenters 0169 and 0172.5
opine that the EPA may not infringe on NRC authority by proposing an alternative definition of
lie.(2) material.
Commenter 0172.5 also thinks that the EPA does not have statutory authority to define tailings
as restoration fluid because that authority rests exclusively with the NRC.
Response to Issue 8:
See Section IV.A.2 of the preamble to the final rule for responses to this issue. See also Section 2
of this document for other comments related to the definition of uranium byproduct material or
tailings under Subpart W.
Issue 9: EPA's authority to regulate radon emissions from uranium processing facilities
Summary of Comments Under Issue 9:
Commenter 0167 opposed comments of the regulated industry which argued that the EPA does
not have authority to directly regulate radon emissions from uranium processing facilities.
Commenter 0167 argued that the industry's arguments amount to an argument the EPA lacks
authority over emissions from uranium mill tailings impoundments. Commenter 0167 opined
that if industry wishes to remove a tailings facility from NESHAP regulation, it should submit a
petition showing that radon emissions are not hazardous, but believes that such an effort would
fail. Commenter 0167 continued that the EPA's proposed rule continues to recognize the health
hazards of uncontrolled radon emissions from uranium mill tailings and the rulemaking record
confirms that CAA NESHAP regulation is a necessary part of the EPA's role in regulating
uranium mill tailings pursuant to its CAA and UMTRCA authorities.
Numerous commenters supported the EPA's decision to regulate radon emissions from uranium
mill facilities. Specifically, Commenters 0173.8 and 0186 state that the EPA has authority to
regulate all radon at mills and Commenter 0173.3 confirmed that the EPA has a role in
regulating uranium mill tailings. Commenter 0173.6 stated that the EPA has authority to conduct
radon flux measurements.
Response to Issue 9:
See Section IV.A.2 of the preamble to the final rule for responses to this issue.
Final
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U.S. Environmental Protection Agency
Office of Radiation and Indoor Air
EPA 402-R-l 6-004
NESHAPS Subpart WResponse to Comments
Issue 10: Public opportunity to comment on construction of tailings impoundments
Summary of Comments Under Issue 10:
Commenters 0153 and 0172.8 commented that the EPA or Utah Division of Air Quality should
be required to provide an opportunity for public comment on any application to construct a
tailings impoundment, pursuant to 40 CFR 61.07 and that there has always been a requirement
for approval of new impoundments because a uranium recovery licensee must apply for a
construction authorization.
Response to Issue 10:
The provisions requiring application for approval of construction or modification at 40 CFR
61.07 are contained in the 40 CFR part 61 General Provisions (subpart A), which are applicable
to the owner or operator of any stationary source for which a standard is prescribed under 40
CFR part 61. See 40 CFR 61.07(c). Therefore, the requirements of 40 CFR 61.07 are applicable
to sources subject to Subpart W. The EPA did not propose any changes to the §61.07
requirements or applicability for Subpart W sources, therefore these comments are beyond the
scope of this rulemaking.
Final
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Office of Radiation and Indoor Air
EPA 402-R-l 6-004
NESHAPS Subpart WResponse to Comments
Seel i"i i 1 I V u11 mrn i i t' i n i n h a ! \ f cocluet Material
Section 2 - Definition of Uranium Byproduct Material 9
Issue 1: Suggestion that EPA distinguish between "tailings" and "byproduct material" for its
CAA authority 10
Issue 2: Consistency between EPA's CAA definition of byproduct material and the AEA/NRC
definition 10
Issue 3: Regulation of treated water if it does not contain byproduct material 11
Issue 4: Clarification regarding whether liquids are byproduct material or contain byproduct
material 11
Final
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U.S. Environmental Protection Agency
Office of Radiation and Indoor Air
EPA 402-R-l 6-004
NESHAPS Subpart WResponse to Comments
Issue 1: Suggestion that istingiiisli between "tailings" and "byproduct material" for
its CAA authority
Summary of Comments Under Issue 1:
Several commenters addressed the definition of "uranium byproduct material or tailings" in
Subpart W. Commenters generally raised the distinction between "tailings" and "byproduct
material" under the AEA as germane to the scope of this rulemaking (see also Issue 2 in this
section). Commenter 0169 suggests that the historical focus on conventional mill tailings
impoundments (or "piles") is linked to the CAA, and that we are impermissibly re-defining non-
tailings byproduct material as "tailings" as a means to address them under the CAA. Commenter
0172.5 noted the following in referring to the AEA definition: "All tailings are byproduct
material, but not all byproduct materials are tailings." Commenter 0144 asks for clarification on
how restoration fluids may be considered byproduct material.
Commenter 0153 raises an additional question regarding wastes at uranium recovery facilities
that do not derive from ores. The commenter stated that such wastes may derive from "alternate
feed" materials that contain sufficient uranium to make processing worthwhile (e.g., tailings
from other mineral extraction operations), or could include wastes placed directly into
conventional impoundments because they are physically or chemically similar to the material
already being managed.
Commenter 0172.2 opposes the proposed regulation of heap leach piles under Subpart W. The
commenter believes that material remaining in the heap does not become byproduct material
until processing is completed.
Commenter 0144 notes that uranium is also produced as a byproduct at other mineral recovery
facilities and asks for clarification on the status of the wastes from such operations.
Response to Issue 1:
See Sections IV. A.2 and IV.F.2 of the preamble to the final rule for responses to comments on
the definition of "uranium byproduct material or tailings." See Section IV.D.2 of the preamble to
the final rule for responses to comments related to heap leach piles. Regarding the production of
uranium as a byproduct of other mineral production operations, Subpart W applies to "owners or
operators of facilities licensed to manage uranium byproduct materials during and following the
processing of uranium ores." 40 CFR 61.250. If a facility is licensed to conduct such activities, it
would be subject to Subpart W.
Issue 2: Consistency between EPA's CAA definition of byproduct material and the
A EA/N IRC definiti on
Summary of Comments Under Issue 2:
A number of commenters noted the difference between the definition of "uranium byproduct
material or tailings" in Subpart W and the definitions of "byproduct material" in section 1 le.(2)
of the Atomic Energy and in 10 CFR part 40 (see also the response to Issue 1 in this section). In
Final
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U.S. Environmental Protection Agency
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EPA 402-R-l 6-004
NESHAPS Subpart WResponse to Comments
particular, several commenters (0154/0170, 0172.5, 0173.10) stated that the Nuclear Regulatory
Commission (NRC), not the EPA, has exclusive authority over the definition of 1 le.(2)
byproduct material, as well as the material itself. Commenters question EPA's authority to
promulgate a new definition of "1 le.(2) byproduct material" or to equate the definition to the
term "mill tailings." The commenters opine that EPA may not infringe on NRC authority by
proposing an alternative definition of 1 le.(2) byproduct material. Commenter 0169 also thinks
that the EPA does not have statutory authority to define tailings as restoration fluid because that
authority rests exclusively with NRC.
Several commenters (0154/0170, 0159, 0162, 0165, 0186) also suggested that we modify the
definition in Subpart W to be identical to NRC's definition in 10 CFR 40.4.
Response to Issue 2:
See Sections IV. A.2 and IV.F.2 of the preamble to the final rule for responses to this issue.
Issue 3: Regulation, of treated water if it does not contain byproduct material
Summary of Comments Under Issue 3:
We received some comments from industry opposing our proposed requirements for non-
conventional impoundments on the grounds that certain impoundments may be used to hold
treated effluents from which byproduct material has been removed. Commenters 0107 and 0144
believe we need to define a threshold level which no longer constitutes byproduct material.
Commenters 0154/0170 and 0173.9 believe that liquids treated to meet effluent standards should
no longer be regulated. Commenter 0186 disagrees "because the radium content could increase
during evaporation" and the same construction standards should apply. See also Issue 4 in this
section and Section 6 of this document.
Response to Issue 3:
See Section IV.E.2 of the preamble to the final rule for responses to this issue. Liquids can be
treated to effectively remove uranium and radium such that their concentrations remain low,
even if evaporation occurs.
Issue 4: Clarification regarding whether liquids are byproduct material or contain
byproduct material
Summary of Comments Under Issue 4:
Commenter 0153 wishes us to be more clear that solids and liquids in impoundments are
byproduct material. Commenters 0159 and 0162 also wish us to clarify this point, specifically
whether byproduct material can be removed from process liquids (see also Issue 3 above).
Response to Issue 4:
See Section IV.F.2 of the preamble to the final rule for responses to this issue.
Final
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U.S. Environmental Protection Agency
Office of Radiation and Indoor Air
EPA 402-R-l 6-004
NESHAPS Subpart WResponse to Comments
Seel I vs. MACT
Section 3 - GACT vs. MACT 12
Issue 1: Request that EPA define major and area sources and opinion that CAA 112(d)
requires MACT for sources not so defined 13
Issue 2: Justification for using MACT instead of stronger MACT 13
Issue 3: Requirement under CAA 112(h) for an emission standard unless not feasible 13
Issue 4: Appropriateness of typical mass-based definition of major source for uranium
byproduct material impoundments 14
Issue 5: Data supporting EPA's justification for GACT as effective at newer impoundments 14
Issue 6: Treatment of liquid effluents to remove radium 15
Issue 7: Extreme weather events 16
Final
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U.S. Environmental Protection Agency
Office of Radiation and Indoor Air
EPA 402-R-l 6-004
NESHAPS Subpart WResponse to Comments
Issue 1: Request that EPA define major and area sources and opinion that CAA 112(d)
requires M ACT for sources not so defined
Summary of Comments Under Issue 1:
Several commenters (0153, 0155, 0156, 0167) believe our use of GACT to control radon
emissions from uranium byproduct material under Subpart W is in violation of the Clean Air
Act. The commenters refer to CAA §112(d)(5), which allows the Administrator to designate
GACT, rather than MACT, for area sources listed under CAA §112(c)(3). The commenters note
that EPA has not included sources subject to Subpart W on the list of area sources.
Response to Issue 1:
See Section IV.A.2 of the preamble to the final rule for responses to this issue.
Issue 2: Justification for using MACT instead of stronger MACT
Summary of Comments Under Issue 2:
Some commenters stated that the designation as an area source is not in itself sufficient to justify
use of GACT. Commenters 0131 and 0132 cite the legacy of contamination associated with the
uranium industry as justifying the "strongest preventive measures." Similarly, Commenters 0143
accuses the industry of "cutting corners" and Commenter 0152 believes GACT "runs counter to
everything EPA knows" about past practices. Commenter 0153 argues that the Agency's
"discretion" must be supported by full and complete explanation and justification. These and
other commenters (0157, 0163, 0166, 0167, 0173.3) also believe EPA has not sufficiently
considered MACT approaches.
Response to Issue 2:
See Section IV.C.2 of the preamble to the final rule for responses to this issue. While this section
of the preamble specifically addresses comments on the GACT management practices applicable
to conventional impoundments, the response as it regards the Administrator's authority to set
CAA standards applies more broadly to all sources regulated under Subpart W. The CAA does
not require a consideration of MACT approaches before setting GACT-based standards for area
sources.
Issue 3: Requirement under CAA 112(h) for an emission standard unless not feasible
Summary of Comments Under Issue 3:
Commenter 0153 states that CAA §112(h) prohibits the use of work practices in lieu of emissions
standards unless the Administrator determines that it is not feasible to establish emissions standards.
Response to Issue 3:
See Section IV.A.2 of the preamble to the final rule for the response to this issue. See also Section 1 of
this document.
Final
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U.S. Environmental Protection Agency
Office of Radiation and Indoor Air
EPA 402-R-l 6-004
NESHAPS Subpart WResponse to Comments
Issue propriateness of typical mass-based definition of major source for uranium
byproduct material iinpoun.dmen.ts
Summary of Comments Under Issue 4:
Commenter 0155 believes that it is inappropriate for EPA to rely upon the CAA §112(a)(1) emissions
threshold of 10 tons per year to categorize uranium byproduct management structures as area sources.
The commenter considers it "absurd" to apply this threshold to radionuclides, and asserts that this
"exceed[s] the amount of radioactive material released over a short period of time in a nuclear disaster."
Response to Issue 4:
See Section IV.A.2 of the preamble to the final rule for responses to this issue.
Issue 5: Data supporting EPA's justification for G.ACT as effective at newer
impoundments
Summary of Comments Under Issue 5:
Several commenters (0153, 0155, 0158, 0167, 0173.3) believe our designation of GACT is unsupported
because there is no monitoring data to demonstrate the effectiveness of the measures for post-1989
impoundments. Commenters criticize the analysis of control technologies in the Background
Information Document (BID) prepared to support the proposal as flawed and insufficient. Commenter
0153 states that limiting the size of the impoundment is not in itself an effective means to limit radon
emissions without monitoring, reporting, and the requirement of liquid or soil application. This
commenter, as well as Commenter 0185, also believe that any new impoundments should be required to
use the continuous disposal method, as the commenters view the phased disposal method as ineffective
in controlling radon emissions, particularly when using water cover. Commenter 0153 further disputes
the reliance on 40 CFR 192.32(a)(1) as an effective control technology to limit radon emissions.
Commenter 0155 also suggests that the most effective control technology is an emissions limit coupled
with monitoring, and believes the rule should be re-crafted along those lines. Commenter 0158 agrees
with Commenter 0155 and specifically refers to the Cotter facility's "wide fluctuations in radon flux
between 2000 and 2011" as demonstrating the need for monitoring. The commenter further asserts that
Cotter is a "prime example" of the failure of GACT, citing the facility's experience in maintaining a
water cover in its impoundments.
Commenters also do not believe we have sufficiently examined other technologies employed either in
other countries or in related industries. Commenter 0167 argues that other technologies (e.g., dry-stack
placement, paste tailings, solidification) may be superior to open-air storage and cover in conventional
impoundments, but were not evaluated in the BID. Commenter 0153 believes we should specify that
impoundments have berms to limit wind turbulence and use barium chloride to precipitate radium from
solution.
Response to Issue 5:
The final rule retains the radon flux standard and monitoring requirement for conventional
impoundments in existence on December 15, 1989. We find that the reasoning employed for specifying
Final
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Office of Radiation and Indoor Air
EPA 402-R-l 6-004
NESHAPS Subpart WResponse to Comments
work practices for newer impoundments in the 1989 rule (designated as GACT management practices in
the final rule), namely the ability to control their size and construction, remains valid.
Contrary to Commenter 0158's assertions, practices undertaken to limit radon emissions appear to have
been effective at the Cotter facility. Radon flux data reported by Cotter for the period 1999-2009 does
not indicate that annual emissions exceeded the 20 pCi/m2-sec standard. This information was submitted
by the commenter and may also be found in Table 18 of the updated risk assessment (Docket No. EPA-
HQ-OAR-2008-0218-0078). Regardless of the fluctuation in reported results over this period, and taking
the commenter's point that there may have been periods during which radon emissions were increased
because soil or water cover was not maintained, we find that this situation supports our statement at the
time of the 1989 rule that "This rule will have the practical effect of requiring the mill owners to keep
their piles wet or covered." 54 FR 51689. We recognize stakeholders' concerns with the Cotter facility
and whether its monitoring was properly conducted or enforced, but we do not find this to be a failure of
the GACT approach. The Cotter facility is being decommissioned and remediated as a Superfund site, so
is no longer subject to the requirements of Subpart W.
See Section IV.C.2 of the preamble to the final rule for responses to comments related to the
effectiveness of GACT for conventional impoundments constructed after December 15, 1989, including
discussion of alternative technologies. See Section IV.E.2 of the preamble to the final rule for responses
related to specifications for non-conventional impoundments. As discussed in that section (see also Issue
7), the Administrator expects that the design and engineering requirements for impoundments will
protect against reasonably foreseeable weather events, including potential wind turbulence. We do not
find it necessary to specify the construction of berms for that purpose in Subpart W. See also Issue 6
regarding treatment of liquid effluents.
Issue 6: Treatment of liquid effluents to remove radium
Summary of Comments Under Issue 6:
Commenters 0153 and 0185 assert that liquids in non-conventional impoundments have been
underestimated by EPA as a source of radon emissions. The commenters believe these sources must be
monitored and licensees must be required to treat effluents to remove radium. Commenter 0155 also
states that EPA should not pre-determine low emissions from non-conventional impoundments.
Response to Issue 6:
See Section IV.E.2 of the preamble to the final rule for responses to this issue. As described in that
response, the commenters' data do not support their contention that we have underestimated radon
emissions from liquids. We find that it is not necessary to require treatment of effluents to remove
radium.
Final
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U.S. Environmental Protection Agency
Office of Radiation and Indoor Air
EPA 402-R-l 6-004
NESHAPS Subpart WResponse to Comments
Issue 7: Extreme weather events
Summary of Comments Under Issue 7:
Commenter 0153 states that the current and proposed rules do not actually contain any measures to
control releases during extreme weather events. The commenter asserts that EPA has not provided any
data to support the conclusion that the requirements of 40 CFR 264.221 will prevent dispersion of
contents in severe events. The commenter expresses concern that generally available technologies do not
exist that could prevent dispersion of contents or failure of the impoundment in a severe event such as a
tornado or hurricane.
Response to Issue 7:
See Section IV.E.2 of the preamble to the final rule for responses to this issue.
Final
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U.S. Environmental Protection Agency
Office of Radiation and Indoor Air
EPA 402-R-l 6-004
NESHAPS Subpart WResponse to Comments
Seen-ii I ' usidering All Radionuclides Emitte i Uf inium
Recovery Facilities
Section 4 - Considering All Radionuclides Emitted at Uranium Recovery Facilities 17
Issue 1: Evaluating and considering all HAPs, including Th-232 decay products 18
Issue 2: Evaluating and considering all sources of radionuclides at uranium recovery facilities
19
Issue 3: Evaluating alternative monitoring methods 19
Final
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U.S. Environmental Protection Agency
Office of Radiation and Indoor Air
EPA 402-R-l 6-004
NESHAPS Subpart WResponse to Comments
Issue 1: Evaluating and considering all HAPs, including Th-232 decay products
Summary of Comments Under Issue 1:
A number of commenters expressed the view that EPA should not limit the scope of Subpart W
to Rn-222. Commenter 0153 believes EPA must take this approach in order to support a source
category listing for uranium recovery facilities. Commenter 0153 also states that the White Mesa
Mill has been authorized to accept materials that are high in Thorium-232 content. Thorium-232
decays through Radium-228, Radium-224 and then to Radon-220 (also known as thoron). The
commenter notes that the facility has developed special handling procedures for these wastes.
The commenter believes that EPA is well aware that other radionuclide HAPs are being emitted
at uranium recovery facilities and should require facilities to monitor for them. Similarly,
Commenter 0155 believes that non-radionuclide HAPs are present and need controlling. The
commenter notes that little information on these substances is available from the facilities, and
believes EPA should rectify this situation.
Commenter 0173.8 expresses concern that EPA's risk assessment to support the proposal does
not adequately consider radon progeny (decay products). The commenter points to an NRC
guidance that attributes most radon dose to the decay products (such as lead). The commenter
also believes that radon in ground water may present a greater threat and notes that no
comprehensive epidemiological studies have been done for the populations surrounding the
Cotter facility.
Response to Issue 1:
We are aware that there is the potential for other HAPs (radionuclide and non-radionuclide) to be
emitted at uranium recovery facilities. See Section IV. A.2 of the preamble to the final rule for
the response to Commenter 0153 regarding the need to identify all HAPs to support a source
category listing for uranium recovery facilities.
In response to Commenter 0153, the presence of other radionuclides in wastes placed into
impoundments, and even in fairly high concentrations, does not necessarily translate into an off-
site hazard from air emissions. Nor does a special handling procedure for certain radionuclides,
which is likely implemented to protect workers from more immediate exposures. Radium-228
has a half-life of slightly more than 5 years (compared to 1,600 years for Radium-226), and
Radon-220 has a half-life of slightly less than one minute (compared to more than three days for
Radon-222), so these more rapidly-decaying radionuclides would present a more significant
health and safety concern for workers. However, this also means that Radon-220 is far less likely
than Radon-222 to reach the surface of an impoundment or, if it does, to reach an off-site
receptor.
In response to Commenter 0155, Subpart W is one of a series of NESHAPs developed
specifically to address radionuclides. The Agency has not determined that uranium mills or other
uranium recovery facilities represent a significant source of other HAPs, nor did we propose to
extend the scope of Subpart W to HAPs other than Radon-222.
In response to Commenter 0173.8, EPA's risk assessment does evaluate the impacts to off-site
receptors of radon and its progeny. It is well-understood that the greatest impacts from exposure
Final
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U.S. Environmental Protection Agency
Office of Radiation and Indoor Air
EPA 402-R-l 6-004
NESHAPS Subpart WResponse to Comments
to radon come from its radioactive progeny. However, for purposes of Subpart W, the air
pathway is the primary pathway of concern (that is, radon traveling through the air, but also
considering re-suspension of soil containing lead, polonium, or other decay products). Radon in
ground water would not be expected to be a significant hazard, although this would depend to
some extent on site-specific conditions (e.g., ground water travel time and chemistry, magnitude
of the radionuclide source term). As a Superfund site, remediation and remedy selection for the
former Cotter mill and associated properties will take into account all exposure pathways in a
more detailed fashion than did our risk assessment to support this rulemaking.
Issue 2: Evaluating and considering all sources of radionuclides at uranium recovery
facilities
Summary of Comments Under Issue 2:
Commenters 0153, 0155, 0156, 0161, 0172.8 and 0186 believe that Subpart W should also take
into account non-waste sources of radon, such as ore stockpiles, alternate feed materials, and
contaminated soils.
Response to Issue 2:
See Section IV.A.2 of the preamble to the final rule for the response to these comments. As a
practical matter, Subpart W has not been applied to other sources of radon at uranium recovery
facilities where wastes are present, such as material in thickeners or other processing units. The
NRC, or NRC Agreement State, regulates the radionuclide emissions from all sources at a
uranium recovery facility. The operator is required to report particulate radionuclide and Rn-222
concentrations at the facility boundary. Thus, radon emissions from sources not covered under
Subpart W, including those from the raw ore in heap leach piles or processed yellowcake, are
captured by the NRC reporting requirements.
Further, the EPA is taking this action pursuant to CAA § 112(q). The 1990 Amendments, which
added CAA § 112(q), explicitly provides that § 112 standards in effect prior to the date of
enactment of the 1990 CAA Amendments shall remain in force and effect after that date. CAA §
112(q)(l) also provides that: "Each [standard in effect before the enactment of the CAA
Amendments of 1990] shall be reviewed and, if appropriate, revised to comply with the
requirements of subsection (d) of this section... " In sum, Congress clearly intended that (1)
standards promulgated prior to 1990 remain in effect; and (2) the EPA may update the standards,
as appropriate. CAA § 112(q) does not direct the EPA to expand the scope or applicability of the
regulation at issue.
Issue 3: Evaluating alternative monitoring methods
Summary of Comments Under Issue 3:
Commenter 0153 states that the monitoring method used by the White Mesa Mill "does not
capture and measure radon-220 or radon-220 progeny." The commenter doubts that other
devices in the vicinity of the site are capable of such measurements.
Final
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U.S. Environmental Protection Agency EPA 402-R-l 6-004
Office of Radiation and Indoor Air NESHAPS Subpart W Response to Comments
Response to Issue 3:
Subpart W does not require measurements of radon-220 or its progeny.
Final
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U.S. Environmental Protection Agency
Office of Radiation and Indoor Air
EPA 402-R-l 6-004
NESHAPS Subpart WResponse to Comments
Seel»• in M1111mating lit Mstincti ii nh I listing Impoundments
Section 5 - Eliminating the Distinction with Existing Impoundments 21
Issue 1: Grandfathering non-conventional impoundments that are already approved 22
Issue 2: Monitoring and emissions standard for existing impoundments 22
Issue 3: Monitoring and limits for non-conventional impoundments 22
Issue 4: Scope of Subpart W with respect to non-conventional impoundments 23
Issue 5: Monitoring conventional impoundments 24
Issue 6: Restriction on switching of conventional and non-conventional impoundments 24
Issue 7: Clarification of references to construction requirements 25
Issue 8: Level of emission standard based upon current control technologies and data 26
Issue 9: Violations of the current standard and practices 26
Final
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U.S. Environmental Protection Agency
Office of Radiation and Indoor Air
EPA 402-R-l 6-004
NESHAPS Subpart WResponse to Comments
Issue 1: Grandfathering non-conventional impoundments that are already approved
Summary of Comments Under Issue 1:
Commenter 0107 (0173.9) expresses concern that non-conventional impoundments that have
already been approved are not designed to maintain the proposed one meter of liquid cover. This
is of particular concern because the liquid level must remain low enough to avoid overtopping
the embankment. Commenter 0162 expresses similar, but more general, concern that recent
approvals of both conventional and non-conventional impoundments will remain valid. The
commenter requests that the final rule explicitly address this situation.
Response to Issue 1:
See Section IV.E.2 of the preamble to the final rule for responses to comments related to the
liquid level in non-conventional impoundments and the impact on recent approvals. More
generally, the final rule retains the requirement that impoundments must meet the criteria in 40
CFR 192.32(a)(1), and clarifies that this requirement applies to both conventional and non-
conventional impoundments. Therefore, recent approvals should not be impacted by the final
rule.
Issue 2: Monitoring and emissions standard for existing impoundments
Summary of Comments Under Issue 2:
Many commenters opposed the proposed elimination of the monitoring requirement for
conventional impoundments in existence on December 15, 1989 (0131, 0132, 0143, 0145, 0153,
0155, 0161, 0173.2, among others). Commenters expressed a general concern that no data would
be available, but several also specifically questioned our rationale for doing so. They provided
information indicating that the three "existing" (i.e., pre-1989) impoundments would not be able
to meet the work practice standards (now designated as GACT) (e.g., Commenters 0151, 0153,
0155, 0162 and 0172.3).
By contrast, Commenters 0159 and 0162 supported eliminating the monitoring requirement,
based on the effectiveness of the work practice standards.
Response to Issue 2:
See Section IV.B.3 of the preamble to the final rule for responses to this issue.
Issue 3: Monitoring and limits for non-conventional impoundments
Summary of Comments Under Issue 3:
We received some comment on the proposal to not place limits on either the number or size of
non-conventional impoundments. Commenter 0145 opposed the proposal, and also expressed
support for monitoring these impoundments. Commenter 0173.4 supported the proposal, at least
as it applies to ISL facilities.
Final
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EPA 402-R-l 6-004
NESHAPS Subpart WResponse to Comments
We requested information on appropriate monitoring methods for liquid-covered impoundments
and received some suggestions from Commenters 0159 and 0162 that Large Area Activated
Charcoal Canisters (LAACCs) have been used to collect data from liquid surfaces. Commenters
0159 and 0162 supported the proposal. Commenter 0153 opposed the proposal and supported
monitoring for non-conventional impoundments, suggesting that EPA would prefer not to know
if facilities are not controlling radon emissions.
Response to Issue 3:
Non-conventional impoundments are used to manage process liquids during the operation of the
facility. These liquids may be evaporated or held for recycling back into the process. We
proposed that non-conventional impoundments not be limited in size or number, because they
may be important for operational flexibility, and as long as they are managing liquids and any
solid materials remain saturated, radon emissions will be substantially reduced. We also
proposed that non-conventional impoundments not be subject to monitoring. At the time of the
proposal, we were unable to identify reliable methods for monitoring liquid surfaces (Method
115, the specified method for pre-1989 conventional impoundments, is not suitable for liquid
surfaces). Our proposed approach relied upon maintenance of liquids in non-conventional
impoundments to control radon emissions, thereby rendering monitoring unnecessary.
After considering the comments received, the final rule does not limit the size or number of non-
conventional impoundments, nor does it require monitoring. See Section IV.E.2 of the preamble
to the final rule for responses to comments related to the size and number of non-conventional
impoundments. We appreciate the information regarding the potential use of LAACCs for
monitoring of liquid surfaces. We have determined that the requirement in the final rule to
maintain saturation of solids in non-conventional impoundments will adequately control radon
emissions and represents a generally available technology consistent with the broader GACT
approach to the rule. Therefore, it was not necessary for us to further evaluate monitoring
methods. We do not accept the premise of Commenter 0153's statement.
Issue 1 ^ ,-'.4 • i - Hlbpart W with respect to non-conventional impoundments
Summary of Comments Under Issue 4:
Commenter 0151 disputes our statements that the Agency has historically considered non-
conventional impoundments subject to the requirements of Subpart W. The commenter
recommends making this interpretation explicit in the final rule. Commenter 0186 agrees that
"The EPA never regulated evaporation ponds in accordance with the Subpart W requirements."
Response to Issue 4:
See Section IV.A.2 of the preamble to the final rule for responses to this issue.
Final
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U.S. Environmental Protection Agency
Office of Radiation and Indoor Air
EPA 402-R-l 6-004
NESHAPS Subpart WResponse to Comments
Issue 5: Monitoring conventional impoundments
Summary of Comments Under Issue 5:
A number of commenters expressed the view that monitoring should not be limited to
conventional impoundments constructed before December 15, 1989 (Commenters 0131, 0132,
0153, 0157, 0173.2, 0173.5). They asserted that they have little confidence that the management
practices in place for newer impoundments are effectively being implemented, and argue that it
is not possible to verify their effectiveness without monitoring (see also Issue 9 in this section).
The commenters also expressed concern that impoundments that are drying out ("dewatering")
are emitting larger amounts of radon, and that without monitoring the operators are not
compelled to provide additional soil cover (Commenter 0173.2).
Response to Issue 5:
See Section IV.B.3 of the preamble to the final rule for responses to this issue. Although we
proposed that no impoundments would be required to conduct monitoring, the final rule retains
the radon flux standard and monitoring requirement for conventional impoundments in existence
on December 15, 1989.
Issue 6: Restriction, on switching of conventional and non-conventional iinpoun.ciinen.ts
Summary of Comments Under Issue 6:
Some comments noted that impoundments may be used as both conventional and non-
conventional during their active lifetimes. One industry commenter (0154/0170) noted that the
practice of using an impoundment to manage process liquids before beginning to emplace
tailings is an effective means to manage operational capacity, and encouraged EPA to address
this in the final rule. By contrast, Commenter 0155 urged us to prohibit this practice in the final
rule. The commenter expressed concern that this practice could lead to an increased risk of liner
or other failure, and stated that this has already occurred at the White Mesa Mill. The commenter
warns that this is more likely if impoundments are not all constructed to meet the same
standards, and further notes that this practice may create complications for site closure activities
if it is unclear which impoundments will be left in place and which will be removed. The
commenter also raises the possibility that operators will deliberately use conventional tailings
impoundments to hold liquids as a way to avoid restrictions on the number of conventional
impoundments that can operate at any one time.
Response to Issue 6:
We do not find the concerns expressed by Commenter 0155 persuasive, for several reasons. The
same engineering requirements apply to all impoundments constructed since 1992, whether
conventional or non-conventional. It also seems unlikely that operators will leave more
impoundments in place than are truly necessary at the time of site closure, as this will have
implications for license termination and financial sureties. If an operator finds it advantageous to
convert an impoundment that has been accepting solid uranium byproduct material or tailings
into a non-conventional impoundment (or vice versa), even for a relatively brief period, we see
no reason to prohibit that approach as long as the required practices are followed. The operator
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NESHAPS Subpart WResponse to Comments
will ultimately have to close that unit accordingly. For sites that operate over decades, it is not
unreasonable to believe there may be one or more modifications to the facility license and
closure/reclamation plan. Further, this is not an issue at ISL sites, which have become the
dominant method of uranium recovery. The definition of "non-conventional impoundment" in
the final rule acknowledges this practice, and we do not find it necessary to prohibit or limit it.
Issue 7: Clarification, of references to construction requirements
Summary of Comments Under Issue 7:
Commenter 0155 recommends that we provide more specificity regarding the construction
requirements in 40 CFR 264.221 (which are applied through cross-reference to 40 CFR 192.32).
The commenter proposes that the cross-reference to this section be limited to 40 CFR
264.221(c), which includes more robust liner requirements for impoundments constructed after
January 29, 1992 (the commenter prefers that Subpart W directly incorporate these provisions,
rather than cross-referencing). The commenter believes that the less strict liner requirements for
impoundments constructed before that date do not provide the level of ground water protection
envisioned by the Agency. The commenter also requests that inspection requirements be added
to ensure that liners are operating as intended.
Commenter 0151 recommends that the final rule either directly cite 40 CFR 264.221 for the
construction and design requirements, or include them in the rule. The commenter believes this
would limit the potential for confusion and misunderstanding. The commenter specifically notes
the language related to evaporation and precipitation and the requirements of 40 CFR
264.228(a)(2)(iii)(E).
Response to Issue 7:
We disagree with Commenter 0155 that a narrower reference to 40 CFR 264.221(c) is necessary.
This provision was not incorporated into regulation until 1985. 50 FR 28747. Adopting the
commenter's approach would require impoundments constructed before 1985 to upgrade or
close, which we did not propose to require. Those older impoundments are required to comply
with the provisions of 40 CFR 264.221 that are applicable to them. The commenter's approach
would also eliminate consideration of §264.221(d), which allows for an alternative design or
operating practices if "such design and operating practices, together with location
characteristics" would prevent migration of hazardous constituents and allow detection of leaks
at least as effectively as the requirements of §264.221(c). It is not appropriate to eliminate this
flexibility, particularly for sites that may employ improved liner materials or have exceptional
natural characteristics that lend themselves to such a demonstration. The final rule includes
requirements that operators confirm the state of saturation of impoundment sediments, and these
visual inspections can also serve to indicate whether there are problems with the liners. Further,
NRC requirements in 10 CFR part 40, Appendix A, Criterion 8A, require daily inspections of
impoundments.
We have chosen not to adopt Commenter 015l's recommendation. We believe the reference to
40 CFR 192.32(a)(1) provides sufficient clarity for purposes of Subpart W, and retains the
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NESHAPS Subpart WResponse to Comments
connection to the original requirement for impoundment construction, which is located in 40
CFR part 192. Regarding the reference to 40 CFR 264.228, we note that this section applies to
actions to be taken during closure and post-closure. Subpart W does not extend to actions taken
after the impoundment has entered closure.
Issue 8: Level of emission, standard based upon, current control technologies and data
Summary of Comments Under Issue 8:
Some comments favored retaining the emissions standard for conventional impoundments
constructed before December 15, 1989, but at a more stringent level. Commenter 0167 stated
that a standard below 10 pCi/m2-sec would be appropriate, and also that a review of current
control technologies would support a standard of 1 to 5 pCi/m2-sec. Commenter 0156 noted that
the 1989 Background Information Document found that a 6 pCi/m2-sec standard was achievable
and cost effective. Commenter 0173.3 agreed that 4 or 5 pCi/m2-sec would be appropriate,
stating that the 20 pCi/m2-sec standard was established "for economic reasons." This general
view was supported by Commenter 0173.7. Commenter 0167 also expressed concern that EPA
did not evaluate monitoring methods other than Method 115, and specifically referred to the
Landauer RadTrak.
Response to Issue 8:
See Section IV.B.3 of the preamble to the final rule for responses to this issue.
Issue 9: Violations of the current standard and practices
Summary of Comments Under Issue 9:
Several commenters (0167, 0173.2, 0173.6) disputed our statements regarding the effectiveness
of work practices, citing radon monitoring results from the White Mesa Mill in excess of 20
pCi/m2-sec. The comments note that, while averaged results may fall within the standard, large
areas of the impoundment can be well above the standard for extended periods of time,
indicating that the mill operators are not applying soil cover in a timely manner to limit
emissions.
We also received some comment disagreeing with our proposal regarding radon emissions from
non-conventional impoundments (Commenters 0153, 0155, 0173.2, 0185). These comments
present calculated radon emissions based on data from the White Mesa mill, which appears to
contradict our conclusions regarding the effectiveness of water in limiting radon emissions.
Response to Issue 9:
We are familiar with the results submitted by the commenters, which were presented in the BID
supporting the proposed rule. The Agency strongly encourages operators to take the appropriate
actions to limit radon emissions; however, the actual implementation of those measures is a
matter of enforcement, which at the White Mesa Mill is the responsibility of the State of Utah.
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Office of Radiation and Indoor Air NESHAPS Subpart W Response to Comments
See Section IV.E.2 of the preamble to the final rule for responses to comments regarding the
radon emissions from non-conventional impoundments.
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NESHAPS Subpart WResponse to Comments
Section 6 - Evaporation Pond Issues
Section 6 - Evaporation Pond Issues 28
Issue 1: Proposal to retain one meter of liquid in non-conventional impoundments 29
Issue 2: Reliability of measurement methods for liquid levels 29
Issue 3: Clarifying the term "continuous" as it relates to liquid levels 30
Issue 4: Limiting the size and number of non-conventional impoundments 30
Issue 5: Regulation of treated water if it does not contain byproduct material 30
Issue 6: Clarify the amount of radon reduction from liquid cover 31
Issue 7: Use of liquid cover to limit radon emissions instead of monitoring 32
Issue 8: Clarification of the purpose of non-conventional impoundments 33
Issue 9: Request that EPA consider the entire life cycle of non-conventional impoundments up
to removal 33
Issue 10: Construction authorization renewals 34
Issue 11: Evaporation ponds on top of tailings 34
Issue 12: Evidence or justification for EPA's proposal 35
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NESHAPS Subpart WResponse to Comments
Issue 1: Proposal to retain one meter of liquid in non-conventional impoundments
Summary of Comments Under Issue 1:
Many commenters opposed the proposed requirement to maintain one meter of liquid in non-
conventional impoundments. Commenters primarily cited cost and the logistical difficulty of
obtaining and transporting water as making this proposed requirement overly burdensome,
particularly in the arid West (Commenters 0107, 0141, 0144, 0151, 0154/0170, 0159, 0162,
0169, 0172.2, 0173.1, 0173.9, 0173.10).
Commenters 0107, 0172.2, and 0173.9 express concern that impoundments that have already
been approved and operating were not constructed with a depth that could accommodate an
additional meter of water, potentially necessitating costly renovation. Commenters 0154/0170
and 0173.10 noted that this requirement would have effects on facility operation, where it is
necessary to manage holding or evaporative capacity, and to control the characteristics of liquids
that may be recycled through the process. Commenter 0154/0170 also raised the additional
stress on the impoundment liner resulting from one meter of liquid.
Commenters 0151, 0159, 0162, 0169, 0172.2, and 0173.1 questioned the need for this
requirement, and noted statements in previous rulemakings that the difference between saturation
and one meter of water is negligible. Commenter 0141 requested clarification as to whether the
proposed requirement was for one meter of liquid above any solids in the impoundment, or one
meter depth total. Commenters further argued that non-conventional impoundments present a
small risk in any case. Commenters 0144, 0154/0170, and 0173.10 suggested that a better
approach would be to require that solid materials in the impoundment remain saturated, with no
solids visible above the liquid level.
Response to Issue 1:
See Section IV.E.2 of the preamble to the final rule for responses to this issue.
Issue 2: Reliability of measurement methods for liquid levels
Summary of Comments Under Issue 2:
Commenter 0104 finds difficulties in measuring compliance with the proposed one meter liquid
requirement. The commenter believes direct measurements will be difficult because of the
density of sediments and may present health and safety risks to workers. The commenter
suggests that calculations based on mass and liquid balances would be more effective.
Commenters 0107 and 0173.9 make a similar suggestion, that the one meter requirement be
replaced with a calculation to take into account site-specific factors and give operators greater
flexibility. Commenters 0141, 0144 and 0154/0170 expresses similar concerns. Commenter 0144
sees problems with the slope of the impoundment and the distance that must be observed, and
notes that past experience suggests that measuring devices (such as pressure transducers) will
need frequent maintenance and calibration. The commenter prefers to have a simple permanent
indicator allowing visual confirmation, rather than measurement.
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NESHAPS Subpart WResponse to Comments
Response to Issue 2:
See Section IV.E.2 of the preamble to the final rule for responses to this issue.
Issue 3: Clarifying the term "continuous" as it relates to liquid levels
Summary of Comments Under Issue 3:
Commenter 0141 asks for clarification of the proposed requirement that operators keep records
showing that they maintain a "continuous one meter of liquid in the impoundment." The
commenter is concerned that this will require "around-the-clock" measurements and asks that the
word be removed in the final rule.
Response to Issue 3:
The final rule does not require that one meter of liquid be maintained above any solid materials
in the impoundment. Instead, the final rule requires only that solids remain saturated, which will
be demonstrated if solids are not visible above the liquid in the impoundment. Should inspection
find that the liquid has diminished to the point that solids are visible, the operator will have seven
days (or other time specified by the Administrator) to rectify the situation.
Issue niting the size and number of non-conventional impoundments
Summary of Comments Under Issue 4:
Commenter 0143 believes Subpart W should contain limits on the size of non-conventional
impoundments. The commenter believes that larger impoundments are more likely to fail and
limits must be imposed to minimize the potential for ground water contamination. Commenters
0145 and 0155 agree (Commenter 0155 believes the number should also be limited). Commenter
0153 does not believe we have adequately supported our conclusion that the requirements of 40
CFR 192.32(a)(1) will provide protection against extreme weather events and may be subject to
greater turbulence. Commenter 0144 wishes us to clarify that no actual impoundment has been as
large as 80 acres, but this size has been used only for modeling purposes. Commenter 0166
supports the proposed liner requirements and weather protections.
Response to Issue 4:
See Section IV.E.2 of the preamble to the final rule for responses to comments related to the size
and number of non-conventional impoundments, as well as comments related to weather
protection. See also Sections 5 and 7 of this document for additional comments of this nature.
See Section IV.A.2 of the preamble to the final rule for responses to comments related to the
liner requirements, as well as Sections 1 and 5 of this document.
Issue 5: Regulation of treated water if it does not contain byproduct material
Summary of Comments Under Issue 5:
Commenter 0144 believes that Subpart W should not apply to impoundments that only contain
water that has been treated to meet effluent limits. The commenter sees this as having no
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NESHAPS Subpart WResponse to Comments
regulatory benefit, but a potential additional cost to operators who must meet the more stringent
requirements in 40 CFR 192.32(a)(1). Commenters 0154/0170, 0159, 0162, 0173.4 and 0173.9
support this view. The commenter also asks whether the liner designs for treated water storage
ponds at the proposed Dewey-Burdock site meet with EPA's approval. Commenter 0186
disagrees "because the radium content could increase during evaporation" and the same
construction standards should apply.
Response to Issue 5:
See Section IV.E.2 of the preamble to the final rule for responses to this issue. Liquids can be
treated to effectively remove uranium and radium such that their concentrations remain low,
even if evaporation occurs. Decisions regarding the specific question of storage ponds at the
Dewey-Burdock site are the responsibility of EPA Region 8 and are not part of this rulemaking.
Issue 6: Clarify the amount of radon reduction from liquid cover
Summary of Comments Under Issue 6:
Commenter 0144 asks for clarification on the effectiveness of liquid cover. The commenter finds
discrepancies between statements that one meter of water will reduce emissions by 93%, but
saturation or less than one meter will reduce emissions by about 98% compared to dry tailings.
Commenter 0172.2 states that the reduction would be 2%, not 93%.
Response to Issue 6:
The statements can be reconciled by understanding their respective points of comparison. The
preamble to the proposed rule referred to analyses prepared to support the 1986 rulemaking:
"[R]adon emissions from tailings covered with less than one meter of water, or merely saturated
with water, are about 2% of emissions from dry tailings." 79 FR 25398, emphasis added. The
statement cited by the commenter can be found on page 25402 of the proposal, as follows:
"Solving the above equation shows that one meter of water has a radon attenuation factor of
about 0.07. That is, emissions can be expected to be reduced by about 93% compared to no
water cover" (emphasis added). Thus, saturation reduces emission from dry tailings by about
98%), and one meter of liquid cover will provide an additional reduction of about 93%. One
meter of liquid cover would provide a total reduction of about 99.85% compared to dry tailings.
For the final rule, we are using an attenuation factor of nearly 95% for saturated material (see
Figure 12 of the BID) and requiring that liquid levels in non-conventional impoundments be
maintained to cover any solid materials. Even though the level of attenuation is slightly reduced
from the figure cited in the preamble to the proposed rule, the requirement for saturation ensures
that radon emissions from non-conventional impoundments will be controlled to levels that
represent limited risk to public health.
Final
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EPA 402-R-l 6-004
NESHAPS Subpart WResponse to Comments
Issue 7: Use of liquid cover to limit radon emissions instead of monitoring
Summary of Comments Under Issue 7:
Commenters 0153, 0155, 0168, 0172.8, 0185 and 0186 dispute our conclusion that radon
emissions from non-conventional impoundments are minimal and do not believe the risk
assessment fully considered these sources. The commenters provide calculations based on data
from the White Mesa Mill showing that radon emissions are tens to hundreds of times the 20
pCi/m2-sec flux standard applied to existing conventional tailings impoundments. The
commenters further find our description of the processes producing the waste to be lacking in
detail. The commenters do not believe we can say that radon emissions are regulated unless we
impose an emissions standard and monitoring (using an adapted Method 115 or other appropriate
method), or quarterly calculations, and request that we summarize and analyze actual data to
support our position. Commenters also suggest it is necessary to control the radium content of
liquids being added to the impoundments. Commenters 0156 and 0173.2 similarly find that our
assumptions may be faulty. Commenter 0153 also states that the equation in the Background
Information Document was derived for solid tailings with an actual water cover, not to liquids
that contain radium. Commenter 0167 supports an emissions standard of 1 to 2 pCi/m2-sec but
does not believe we have collected sufficient information to determine the appropriate standard.
Commenter 0168 notes that in practice liquid levels can vary significantly depending on rainfall
and evaporation.
Commenter 0172.7 agrees with the proposal that monitoring is not needed and cites research
sponsored by the National Mining Association, which found radon emissions from liquid
surfaces within the range of background. Commenters 0172.9 and 0172.11 agree and cite other
experience and documentation to that effect.
Response to Issue 7:
We believe the description in the BID of the uranium recovery process, and the wastes that result
therefrom, is adequate. In addition to the equation to calculate radon attenuation from solids
covered by liquid, the BID also contains information to estimate radon emissions based upon the
concentration of Ra-226 in the liquid. We agree that liquid levels in non-conventional
impoundments can fluctuate. The final rule requires that liquids be maintained to a level such
that no solid material in the impoundment is visible. See Section IV.E.2 of the preamble to the
final rule for responses to comments related to emissions from non-conventional impoundments
at the White Mesa Mill.
We appreciate the information provided by commenters on testing that has been conducted to
measure radon emissions from liquid surfaces. We also requested information on appropriate
monitoring methods for liquid-covered impoundments and received some comments suggesting
that Large Area Activated Charcoal Canisters (LAACCs) may be effective in monitoring liquid
surfaces. We appreciate the information regarding the potential use of LAACCs, but more testing
and validation of this method would be necessary before it could be accepted for a regulatory
application. We have determined that the requirement in the final rule to maintain saturation of
solids in non-conventional impoundments will adequately control radon emissions and represents
a generally available technology consistent with the broader GACT approach to the rule.
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Therefore, it was not necessary for us to further evaluate monitoring methods. See also Section 5
of this document.
Issue 8: Clarification, of the purpose of non-conventional impoundments
Summary of Comments Under Issue 8:
Commenter 0153 finds the discussion of non-conventional impoundments confusing. The
commenter believes we have inconsistently and inaccurately described the purpose of these
impoundments, the nature of the materials in them, and our regulatory approach. The commenter
wishes us to clarify that the liquids are not held in the impoundments for the purpose of covering
uranium byproduct material, but the liquid in fact contains (or is) uranium byproduct material.
The commenter questions how the liquid can be used to control radon emissions, when the liquid
is itself in need of control, and requests that we consider that liquids high in radium content may
actually cause an increase in emissions. Commenters 0155 and 0156 make similar points.
Commenters 0159, 0161 and 0162 also ask for clarification of the status of the liquid effluents.
Response to Issue 8:
See Section IV.E.2 of the preamble to the final rule for responses to this issue.
Issue 9: Request tl onsider the entire life cycle of non-conventional
impoundments up to removal
Summary of Comments Under Issue 9:
Commenter 0153 requests that we clarify situations where (for example) evaporation ponds are
left only with solids, until the impoundment is removed. The commenter notes that operating
contingencies may lead to decreases in liquid levels. The commenter believes that monitoring
must be required if solid sediments become exposed. The commenter also requests that we
acknowledge that non-conventional (liquid) impoundments may be intended to transition to
accepting solid tailings as a conventional disposal impoundment.
Commenter 0173.11 addresses the potential for conventional uranium milling in Virginia. The
commenter believes this would require a significantly larger number of ponds to handle runoff
and effluents, because the precipitation rate is higher than the evaporation rate. The commenter
questions the assumption that tailings could be dried to allow installation of a permanent radon
barrier under such conditions and recommends that EPA and NRC evaluate the water balance
issue.
Response to Issue 9:
Non-conventional impoundments are subject to Subpart W as long as they are operating. The
final rule requires only that solids in the impoundment remain saturated (covered with liquid).
We do recognize that non-conventional impoundments may transition to use as conventional
impoundments, and this is reflected in the definition adopted for non-conventional
impoundments in the final rule. The impoundment would then need to meet the requirements
Final
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NESHAPS Subpart WResponse to Comments
applicable to conventional impoundments. We believe these operational contingencies can be
addressed by the operator and regulator. Should uranium milling be undertaken in the eastern
part of the country, there will need to be consideration of local conditions.
Issue 10: Construction, authorization renewals
Summary of Comments Under Issue 10:
Commenter 0153 raises two issues with respect to construction authorizations: first, that such
authorization should be required whenever an impoundment is to be reconstructed or replaced;
and second, that there should be a time limit on the authorization so that impoundments are not
indefinitely approved. The commenter suggests five years. The commenter also suggests that
there should be limit to the length of time a facility can remain on standby (10 years is
suggested).
Response to Issue 10:
Subpart A (40 CFR 61.07(a)) requires an application for construction approval for construction
of a new source or modification of an existing source. The review of Subpart W under CAA
§112(q)(l) is limited to the existing rule, which does not address the construction approval
process. The commenter's concerns regarding facilities on standby are addressed through the
NRC licensing process. Facilities are required to renew their licenses periodically, and
impoundment inspection and maintenance requirements continue to apply during standby.
Issue 11: Evaporation ponds on top of tailings
Summary of Comments Under Issue 11:
Commenters 0159 and 0162 believe that an evaporation pond on top of a conventional tailings
impoundment should not be regulated under Subpart W (including liner requirements), because
the conventional impoundment is already regulated. Commenter 0185 believes such ponds
should not be approved because it is "fiction that a water cover on solid tailings serves to
attenuate the radon and reduce the radon emissions to insignificant levels." The commenter cites
radon flux calculations based on data from the White Mesa Mill to support this position.
Response to Issue 11:
We understand the commenters' position to be based on the premise that, if such a non-
conventional impoundment were to leak, the releases would still remain within the larger
conventional impoundment. And if the larger impoundment is operating, the evaporation pond
may fit within the work practices (now GACT) by maintaining sufficient liquid to cover any
solid material in the impoundment. However, we do not believe this question should be
addressed within this rulemaking. This would be a matter for the regulators to determine based
on facility operation and the designated use of the impoundment. We disagree with Commenter
0185 that a water cover is ineffective in reducing radon emissions. See Section IV.E.2 of the
preamble to the final rule for responses to comments related to radon emissions from liquid
surfaces. See also Issue 7 in this section.
Final
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Issue mce or justification for EPA's proposal
Summary of Comments Under Issue 12:
Commenter 0169 finds questionable legal and scientific bases for our proposal to regulate non-
conventional impoundments under Subpart W. The commenter also finds inconsistencies in our
discussion of liner performance, and contrasts our concerns with weather events and the reliance
upon such liners for long periods in 40 CFR part 192. Commenters 0172.2 and 0173.1 agree that
regulation of these impoundments is unwarranted because radon emissions are negligible.
Commenters 0172.1 and 0172.11 express the view that the rulemaking is unnecessary because
radon exposures to real people, as opposed to calculations at the fenceline or flux measurements,
do not rise to a level of concern. Commenter 0172.5 questions the application of Subpart W on
the grounds that the uranium byproduct material in non-conventional impoundments is not
tailings.
Response to Issue 12:
We disagree with the commenters. Regulation of radon emissions from uranium byproduct
material or tailings managed in non-conventional impoundments is well within the Agency's
authority under the Clean Air Act. We have determined that non-conventional impoundments
containing uranium byproduct material or tailings represent a potential source of radon emissions
that warrants control and is amenable to a GACT approach. See also Sections 1 and 2 of this
document for responses to comments related to our legal authority and the definition of uranium
byproduct material or tailings under Subpart W.
Commenter 0169 has mistaken an excerpt from the surface impoundment construction
requirements in 40 CFR 264.221(h) ("In ensuring structural integrity, it must not be presumed
that the liner system will function without leakage during the active life of the unit") for a
statement of policy unique to the Subpart W rulemaking. When designing and constructing dikes
for a surface impoundment, analyses should consider potential leakage rates that could
undermine their structural integrity. As the commenter notes, conventional impoundments are
required under 40 CFR 192.32(b)(l)(i) to be effective for 200 to one thousand years, for which
period releases to groundwater must be limited to prevent contamination.
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Sedi-ii I imih ii 'Ik? Impoundments
Section 7 - Limits on Allowable Impoundments 36
Issue 1: Limiting the total number of disposal cells allowed at a facility 37
Issue 2: Limiting the size of impoundments 37
Issue 3: Counting and approval of liquid impoundments 38
Issue 4: Risk of spills or leaks from larger liquid impoundments 38
Issue 5: Limiting the total number of operating impoundments 38
Issue 6: Approval of new impoundments relative to closure of existing impoundments 39
Final
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NESHAPS Subpart WResponse to Comments
Issue 1: Limiting the total number of disposal cells allowed at a facility
Summary of Comments Under Issue 1:
Commenters 0131 and 0132 believe the history of uranium recovery in the United States calls for
greater limitation on the size and number of conventional tailings impoundments used for
disposal. The commenters find that the continuous disposal method is likely more effective at
controlling radon emissions, but believe there should be size and quantity limitations placed on
such impoundments similar to those using the phased disposal method. They point out EPA's
conclusion that impoundment area is a more significant factor in radon emissions than is depth or
volume.
Response to Issue 1:
The commenters have overlooked a key distinction between the two methods. The continuous
disposal method does not limit the overall area of the impoundment, but does limit the area that
can be exposed, because the tailings are dried first, then emplaced and immediately covered. By
contrast, tailings emplaced using the phased disposal method are typically wet, which inhibits
radon emissions. Thus, the continuous disposal limitation on the exposed area (10 acres)
effectively serves the same purpose as the overall area limitation of two 40-acre impoundments
using the phased disposal method. In its 1989 rulemaking, EPA found that both methods
protected public health with an ample margin of safety, although we also believed that
continuous disposal would be more cost-effective over the life of the facility.
Issue 2: Limiting the size of impoundments
Summary of Comments Under Issue 2:
Many commenters expressed opinions related to limiting the size of impoundments, both
conventional and non-conventional. Commenters 0144, 0154/0170, 0159, 0169, 0173.4, 0173.10
express general support for the proposal not to limit the size of non-conventional impoundments.
Commenters 0152, 0153, 0156, and 0168 believe non-conventional impoundments should be
limited in size. Commenter 0168 disputes our statement that it is reasonable to assume that such
impoundments will not exceed 80 acres in area, simply because one never has. Commenter 0153
further questions our conclusion that 40 acres is a reasonable size restriction for conventional
impoundments using the phased disposal method. The commenter points to the limited operating
history of such impoundments since promulgation of Subpart W in 1989 and expresses the view
that we have given no adequate justification for not imposing a lower limit, such as 10 or 20
acres.
Response to Issue 2:
The 40-acre limit on conventional impoundments using the phased disposal method was adopted
in 1989 because the Agency believed that it represented best industry practice at that time.
("Comments and Responses to Comments - NESHAPs for Radionuclides," EPA/520/1-89-031,
1990, page 61) The Agency has not found information to indicate that impoundments of this size
cannot be operated in a manner that protects public and worker health and the environment. See
Final
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EPA 402-R-l 6-004
NESHAPS Subpart WResponse to Comments
Section IV.E.2 of the preamble to the final rule for responses to comments related to the size of
non-conventional impoundments.
Issue 3: Counting and approval of liquid impoundments
Summary of Comments Under Issue 3:
Commenter 0153 believes that EPA has not enforced the limit on the number of allowable
operating impoundments, because we have not paid sufficient attention to non-conventional
impoundments. This commenter and Commenter 0155 also point to a specific structure at the
White Mesa Mill, Roberts Pond, as an impoundment for managing liquid effluents that never
received approval by EPA under 40 CFR part 61, subpart A.
Response to Issue 3:
The commenter is correct. EPA has not been counting non-conventional impoundments against
the limit of two that may be operated at any one time using the phased disposal method, which is
the method employed by the White Mesa Mill. One purpose of the current rulemaking is to
clarify this situation. The final rule applies this limitation only to conventional impoundments.
The final rule does not limit the number of non-conventional impoundments that may operate at
a uranium recovery facility, but promulgates other criteria that non-conventional impoundments
must meet. Our understanding is that Roberts Pond is now closed.
Issue .k of spills or leaks from larger liquid impoundments
Summary of Comments Under Issue 4:
Commenter 0153 believes that EPA has not given sufficient attention to the potential for larger
impoundments to have spills or leaks. The commenter asserts that EPA has not provided
adequate information to allow comparison of different size impoundments and their ability to
withstand physical stresses, such as those associated with the external environment (temperature,
wind, freeze/thaw cycles) or the hydraulic pressure of liquid contents. The commenter suggests
that very large impoundments may prove to be less resilient, and that size may actually
contribute to these effects (for example, whether greater turbulence is found at larger
impoundments). Commenter 0186 agrees that "large evaporation ponds at ISLs increase the
potential for ground and surface water contamination when there is leakage of the ponds."
Response to Issue 4:
See Section IV.E.2 of the preamble to the final rule for responses to this issue.
Issue 5: Limiting the total number of operating impoundments
Summary of Comments Under Issue 5:
A number of commenters expressed the view that the total number of non-conventional
impoundments should be limited (0153, 0158, 0161, 0168). Commenters 0153, 0155, 0161 and
0185 cite data showing radon emissions well above the 20 pCi/m2-sec standard from non-
Final
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EPA 402-R-l 6-004
NESHAPS Subpart WResponse to Comments
conventional impoundments at the White Mesa Mill. Commenter 0153 believes no more than
three impoundments (conventional and non-conventional) should be allowed to operate at any
one time. Commenter 0161 believes no more than one non-conventional pond should be in
operation. Commenter 0168 believes EPA has not adequately considered the likelihood that large
amounts of unreclaimed uranium byproduct material or tailings will remain at sites if there is no
limit on the number of impoundments that can be operating at any one time.
A similar number of commenters supported the proposal to allow an unlimited number of such
impoundments (0144, 0154/0170, 0159, 0169, 0173.4, 0173.10). Commenter 0144 notes that
most in-situ leach (ISL) facilities use injection wells for disposal of waste waters, not
evaporation ponds.
Commenter 0186 believes the proposal should have addressed the potential for a heap leach
operation to be located at a conventional mill. The potential for multiple operating piles and
multiple operating impoundments that are not being monitored leads the commenter to conclude
that "The EPA should not permit the establishment of a heap leach operation at a conventional
mill."
Response to Issue 5:
EPA has examined the information referred to by Commenters 0153, 0155, 0161, 0168 and
0185. See Section IV.E.2 of the preamble to the final rule for a detailed response to comments
regarding radon emissions from non-conventional impoundments at the White Mesa Mill. Our
analysis of the data presented by the commenters supports our conclusion that liquids contained
in impoundments effectively mitigate radon emissions, and that the liquids themselves are not a
source of radon that needs further control. While the potential for uranium byproduct material or
tailings to remain unreclaimed was an important consideration in placing limits on conventional
impoundments, we do not believe that non-conventional impoundments present the same
concern because they contain significantly less radon-generating material. The final rule does not
apply to heap leach piles during their operational life and will encourage operators of heap leach
facilities to begin the closure process in a timely manner. We are not taking the approach,
requested by Commenter 0186, of prohibiting the licensing of a heap leach operation at a
licensed conventional mill.
Issue 6: Approval of new impoundments relative to closure of existing impoundments
Summary of Comments Under Issue 6:
Commenter 0153 states that new conventional impoundments should not begin to operate until
non-operational impoundments have an approved closure plan and demonstrate compliance with
the radon flux standard. Commenter 0157 goes farther and states that new impoundments should
not receive permission to operate until other impoundments are fully closed.
Response to Issue 6:
See Section IV.F.2 of the preamble to the final rule for responses to comments related to
"operation" and "closure". See also Section 9 of this document.
Final
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Office of Radiation and Indoor Air NESHAPS Subpart W Response to Comments
Seen- ii ^ I nl »m hi 'hi III ¦ »|) Leach
Section 8 - Regulation of Heap Leach Piles 40
Issue 1: Regulating heaps under the CAA during the leaching process 41
Issue 2: EPA's proposed GACT for heap leach piles 41
Issue 3: Adequacy and accuracy of EPA's technical information on the heap leach process .. 42
Issue 4: Suggestions for EPA's final rule related to heap leaching 44
Final
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EPA 402-R-l 6-004
NESHAPS Subpart WResponse to Comments
Issue 1: Regulating heaps under the CAA during the leaching process
Summary of Comments Under Issue 1:
We received significant comment on the regulatory approach in the proposed rule. Most
commenters (Commenters 0154/0170, 0159, 0162, 0169, 0173.10, 0172.2, 0172.4, 0172.12)
disagreed with our proposal to regulate heap leach piles under Subpart W while they are being
processed. These commenters expressed the view that material in the heap leach pile does not
become uranium byproduct material or tailings until processing is complete, including a final
rinse. As stated by Commenter 0154/0170, "Heap leaching is part of the milling process, and the
proposed rules would interfere with such processing operations." The commenter believes that,
in essence, the heap leach pile is analogous to the conventional mill, which we have not
previously proposed to regulate under Subpart W.
Further, several of these commenters stated that heap leach piles will immediately enter into
closure upon the cessation of processing, so there is no period when they are "operating" simply
as uranium byproduct material or tailings management units. As a result, they see no time at
which Subpart W can apply to heap leach piles.
Commenters 0154/0170, 0159 and 0162 raised the distinction between "close in place" piles and
"on-off' piles. Commenters explain that the latter operations involve the removal of the
processed heap and placement in a conventional impoundment. In this case, the commenters
agree that the uranium byproduct material or tailings from the heap, and the impoundment into
which it is placed, would be subject to Subpart W.
By contrast, we received some comment supporting our proposed approach, and recommending
that we establish an emissions standard and monitoring requirements for heap leach piles
(Commenters 0153, 0167 0186, 0188). These commenters agree that, because uranium
byproduct material or tailings is generated within the heap leach pile at the time processing
begins, the pile serves to manage that material during the operation of the facility. These
commenters believe this function brings it under the scope of Subpart W. These commenters also
take a more expansive view, and believe EPA is obligated under the CAA to address the entire
process at heap leach facilities in the final rule. In this approach, Subpart W would apply to ore
stockpiles, ore crushing and heaps that are awaiting processing, as well as to the heap until
placement of the final cover. Commenter 0167 further recommends that open-air heap leaching
not be approved, when leaching can be conducted more safely and with lower emissions inside a
designed enclosure.
Response to Issue 1:
See the responses to these comments in Section IV.D.2 of the preamble to the final rule.
Issue 'II, •'[.loposed < F for heap leach piles
Summary of Comments Under Issue 2:
A significant number of commenters raised objections to the proposed requirement that heap
leach piles be maintained at 30% moisture content as a means to limit radon emissions
Final
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EPA 402-R-l 6-004
NESHAPS Subpart WResponse to Comments
(Commenters 0104, 0153, 0154/0170, 0159, 0161, 0162, 0169, 0172.12, 0173.10). Calculations
submitted by numerous commenters have shown that to maintain a 30% moisture content across
the heap leach pile would require the pile to be almost submerged. The commenters broadly
agreed that this is an unrealistic goal that could severely undermine the stability of the pile.
Further, it would result in a significantly greater hydraulic head, which raises the risk of liner
failure. Several commenters also consider the monitoring requirement to be difficult to
implement. As with the proposal to maintain one meter of liquid in non-conventional
impoundments, concern was also expressed regarding the source of the water (see Section 6 of
this document). Commenters 0104 and 0154/0170 suggested that a simpler water balance, which
would involve calculations of the amount of liquid entering and leaving the pile, would be a
more implementable method of estimating moisture content. Commenter 0154/0170 also offered
an alternative to the moisture requirement, in which a layer of gravel could be placed on the pile
to limit dust and radon emissions. The leaching solution would be applied through the gravel
layer. The commenter sees this as more workable, but believes such approaches should be
addressed in licensing, not through Subpart W.
Response to Issue 2:
See the response to these comments in Section IV.D.2 of the preamble to the final rule. We
appreciate the suggestion of an alternative method to help reduce radon emissions.
Issue 3: Adequacy and accuracy of EPA's technical inform all on on the heap leach
process
Summary of Comments Under Issue 3:
A number of commenters requested additional information on the heap leach process or
commented that EPA's descriptions of the heap leach process in the proposed rule were
incomplete or incorrect. Commenter 0153 broadly criticizes the discussion in the preamble to the
proposed rule and the BID as not fully characterizing the potential sources of radon found
throughout the operation, or when the emission potential is greatest. This commenter also
disputes our conclusion that work practices are effective at limiting radon emissions from heap
leach piles, since no such facilities are operating. The commenter does not believe we have
sufficiently investigated control technologies for heap leach piles. Finally, the commenter finds
no basis for the proposal's estimate of the number of sampling locations for testing the moisture
content of the heap. The commenter also notes an industry presentation to NRC and requests that
we reconcile statements in that presentation with our proposal. Commenter 0186 finds that our
description of heap leach facilities did not recognize the number of impoundments anticipated
for managing different liquid effluents.
Several commenters (0154/0170, 0159, 0162) noted that the assumption that an acidic solution
will be used for heap leaching may be incorrect. Alkaline solutions have been used previously
and may be more appropriate for some types of ore. Commenter 0172.12 provided general
information on different types of heap leaching (on-off and vat, as well as conventional).
Final
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EPA 402-R-l 6-004
NESHAPS Subpart WResponse to Comments
Commenter 0172.12 generally agrees with our statements that heap leach piles would have lower
radon emissions than conventional impoundments of similar size and condition, because of the
lower-grade ore. However, Commenter 0154/0170 notes that our assumption may not be
accurate. While the ore in the heap leach pile is lower grade, tailings in the impoundment are
likely to be more saturated, which will inhibit radon emissions. The commenter suggests
emissions will be similar for the two sources.
Response to Issue 3:
Many of these comments touched on topics discussed in Issues 1 and 2 in this section. We
appreciate the additional information provided by commenters. The information EPA relied on to
support the proposal was adequate for that purpose, and we note that we requested comment on
some specific aspects of the heap leach process. After considering public comments, the final
rule does not apply to heap leach piles during processing or during the closure process. We
believe this will provide incentive for licensees to begin the closure process for heap leach piles
that have completed their operational life. The final rule includes limits on the size and number
of heap leach piles that can be in the state between processing and closure, but does not specify
that they be kept to a specific level of moisture or have soil applied to reduce radon emissions.
To address Commenter 0186's point, non-conventional impoundments associated with heap
leach operations that contain uranium byproduct material or tailings are regulated under the final
rule.
Commenter 0153 calls attention to statements that the commenter believes are unsupported. We
agree with the commenter that there is no experiential basis to conclude that the work practices
applicable to conventional impoundments have also been effective for heap leach piles, simply
because no such facilities have operated since Subpart W has been in effect. We further accept
the commenter's view that the number of sampling locations to check moisture content for a
heap leach pile may not be directly comparable to the number of sampling locations for
monitoring radon emissions a conventional impoundment using Method 115, even if the areas
are nominally the same. The final rule does not contain a required level of moisture for heap
leach piles, so there is no need to determine the proper number of sampling locations.
Commenter 0154/0170 provides additional perspective regarding the relative radon emission
potential of conventional impoundments and heap leach piles. Another factor that may be
relevant is the physical matrix of material that has been processed through a conventional mill,
compared to what is essentially (in physical form) raw ore. Radon may be more tightly bound by
the conventional waste material, which would likely tend to lower the emission rate from the
conventional impoundment.
Regarding the industry presentation referenced by Commenter 0153, we note that it took place
several years before our proposal was issued. The EPA is not responsible for assumptions made
by regulated parties in the absence of specific requirements.
Final
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EPA 402-R-l 6-004
NESHAPS Subpart WResponse to Comments
Issue 4: Suggestions for al rule related to heap leaching
Summary of Comments Under Issue 4:
Commenter 0154/0170 provided a number of suggestions for revising the proposed rule as it
relates to heap leach piles. These include a separate definition of "heap leach facility," a
distinction between conventional impoundments and heap leach piles that are closed in place,
and inclusion of fully leached ore in a revised definition of "tailings." The commenter also
suggests eliminating the proposed definition of "heap leach pile operational life," although it is
"not unreasonable" should EPA decide to retain it in the final rule. Similarly, Commenter 0186
believes the definition of "operation" as it applies to heap leach facilities must cover activities
beginning with the receipt of ore at the site.
Response to Issue 4:
We appreciate Commenter 0154/0170's suggestions and have considered them for the final rule.
We are retaining the proposed definition of "heap leach pile operational life" and the references
to heap leach facilities or piles in other definitions. We are not adopting the commenter's other
suggestions. The fact that the final rule does not apply to heap leach piles during their
operational life, or after the pile has entered the closure process, as well as clarification regarding
when final closure begins, addresses the commenter's concerns. If the heap leach pile enters the
closure process immediately after processing has completed, as was indicated by industry
commenters, heap leach piles will not be subject to Subpart W at any time. For similar reasons,
we are not adopting the suggestion of Commenter 0186.
Final
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EPA 402-R-l 6-004
NESHAPS Subpart WResponse to Comments
Section ^ ! Vibtitan i - V r .rr )fi/Closiire
Section 9 - Definition of Operation/Closure 45
Issue 1: Extending "operation" through completion of final closure and installation of final
cover 46
Issue 2: Expanding the definition of "operation" to address all phases of operation that
generate radon 46
Issue 3: Implications for regulatory oversight of EPA's proposed definition 47
Issue 4: Including an approved closure plan and milestones in the facility license 48
Issue 5: Applicability of Subpart W to new impoundments at "closed" sites 48
Issue 6: Operations as it involves placement of tailings from process operations, or use for
evaporative or holding purposes 49
Issue 7: Implications of existing and proposed definitions 49
Issue 8: Extending operations through final closure as it affects actual facility operations 51
Final
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EPA 402-R-l 6-004
NESHAPS Subpart WResponse to Comments
Issue 1: Extending "operation" through completion of final closure and installation of
final cover
Summary of Comments Under Issue 1:
A number of commenters advocated that the scope of Subpart W be extended to include all
activities undertaken to achieve final closure of the impoundment (see also Issue 3 in this
section). As defined in Subpart W, "operation" ends "the day that final closure begins" (40 CFR
61.251(e)). Many of the commenters would like this definition extended and explicitly stated that
Subpart W should apply until the final cover is installed on the impoundment (or, for non-
conventional impoundments, until the impoundment is removed, if that is the closure approach).
See Commenters 0131, 0132, 0142, 0143, 0152, 0153, 0157, 0158, 0167, and 0173.7 for
comments of this nature. Commenter 0188 does not want the definition changed (see Issue 8 in
this section), but suggests amending the scope of Subpart W to address impoundments in closure.
The commenter notes that the title of Subpart W as promulgated in 1986 was "National Emission
Standard for Radon-222 Emissions from Licensed Uranium Mill Tailings," and EPA is not
prohibited from adopting a similar title.
Response to Issue 1:
See Section IV.F.2 of the preamble to the final rule for responses to this issue. See also Issues 3
and 4 of this section. In response to Commenter 0188, despite the title of Subpart W as
promulgated in 1986, the "Applicability" section (61.250) clearly stated: "This subpart applies
during the period of operation."
Issue 2: Expanding the definition of "operation" to address all phases of operation that
generate radon
Summary of Comments Under Issue 2:
Commenter 0153 believes the definition of "operation" is too limited to address sources of radon
at uranium recovery facilities. The commenter states that Subpart W must address ore prior to
processing, as well as the processing, spills, etc. This would include all phases of heap leaching,
including heap leach piles that are awaiting processing.
Response to Issue 2:
When the EPA initially promulgated Subpart W in 1986, we identified radon as the radionuclide
released to air that presented the highest risk at uranium recovery facilities and determined that
units managing uranium byproduct material or tailings were the most significant source of radon
emissions. 51 FR 34056. Since 1986 and re-promulgation in 1989, Subpart W has only regulated
units that manage uranium byproduct material or tailings at uranium recovery facilities. 40 CFR
§ 61.250. Other potential emission points in these facilities were not previously the subject of
Subpart W regulation and were not assessed for the 1989 rulemaking. The EPA's CAA § 112(q)
review of Subpart W was limited to the existing standard. Because Subpart W did not regulate
other potential emission points, the EPA did not include any other potential emission points in its
CAA § 112(q) review. EPA did not propose to expand the scope to include ore or the processing
facilities, and has not evaluated the radon emissions from these sources.
Final
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NESHAPS Subpart WResponse to Comments
Thus, Subpart W has not been applied to other sources of radon at uranium recovery facilities
where wastes are present, such as material in thickeners or other processing units. The NRC, or
NRC Agreement State, regulates the radionuclide emissions from all sources at a uranium
recovery facility. The operator is required to report particulate radionuclide and Rn-222
concentrations at the facility boundary. Thus, radon emissions from sources not covered under
Subpart W, including those from the raw ore in heap leach piles or processed yellowcake, are
captured by the NRC reporting requirements.
After considering comments, the final rule will not regulate heap leach piles under Subpart W
during their operational life (i.e., while being processed to extract uranium) or after they have
entered closure. Impoundments used to manage uranium byproduct material or tailings
associated with heap leach operations are regulated under Subpart W. See Section 8 of this
document and Section IV.D.2 of the preamble to the final rule for responses to comments on
heap leach piles.
Issue 3: Implications tor regulatory oversight of EPA's proposed definition.
Summary of Comments Under Issue 3:
Several commenters stated that the current regulatory scheme allows an unacceptable period
during closure activities when impoundments are not being monitored or otherwise managed to
limit radon emissions (Commenters 0153, 0155, 0158, 0167, 0172.14, 0173.6, 0173.7, 0173.8,
0188). They further argue that closure is not being conducted in a manner that will lead to timely
installation of a final cover or removal of an evaporation or holding pond. They cite periods of
decades during which tailings are being "dewatered" or impoundments are used to deposit
wastes from decommissioning activities, while the drying-out of impoundments allows increased
radon emissions. This is attributed in some part to the Agency's rescission of subpart T, which
called for installation of final covers on conventional tailings impoundments within two years of
the cessation of operations. Commenter 0153 notes that an impoundment undergoing closure will
be required to demonstrate compliance with the 20 pCi/m2-sec radon emissions standard if it
requests extension of the milestones in the closure plan, where it may not have been required to
monitor previously under Subpart W. Commenter 0188 notes that subpart T contains an emission
standard, but no compliance requirements during closure. The commenter further questions
whether Agreement States have the enforcement procedures that were required under the 1991
EPA-NRC MOU.
Response to Issue 3:
See Section IV.F.2 of the preamble to the final rule for responses to this issue. See also Issues 1
and 4 of this section. Enforcement procedures, particularly those unrelated to Subpart W, are not
within the scope of this rulemaking.
Final
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EPA 402-R-l 6-004
NESHAPS Subpart WResponse to Comments
Issue 4: Including an approved closure plan and milestones in the facility license
Summary of Comments Under Issue 4:
Commenters 0153, 0155, 0158, 0172.14, 0173.7 and 0188 expressed concern that impoundments
are not being closed in accordance with closure plans, because the plans do not exist, milestones
are absent or unclear, or milestones are not being enforced. Commenters 0153 and 0188 state
that EPA should not consider an impoundment in closure until such plans are incorporated into
the facility license. Commenter 0155 recommends that we amend 40 CFR part 192 to include a
provision that EPA will verify the existence of a closure plan. Commenters 0172.14, 0158 and
0173.7 offer specific comments related to the White Mesa and Cotter sites, respectively, and
what they perceive as a lack of closure plans. Commenter 0188 finds that the situation at White
Mesa regarding the closure of Cell 2 "flies in the face of the EPA and NRC justification for
rescinding Subpart T for operational mills" and believes "There is plenty of justification for
reinstating Subpart T for the White Mesa Mill."
Response to Issue 4:
See Section IV.F.2 of the preamble to the final rule for responses to this issue. See also Issues 1
and 3 of this section. The Agency has no plans to reinstate subpart T.
Issue 5: Applicability of Subpart W to new impoundments at "closed" sites
Summary of Comments Under Issue 5:
Commenter 0153 believes that new impoundments established at sites undergoing closure should
be subject to Subpart W. The commenter suggests that such sites may construct new
impoundments that are actively accepting waste (i.e., they are "operating"), even while the site is
decommissioning. The commenter gives the example of contaminated soils or uranium mine
waste (e.g., waste rock, overburden, or low-grade ore) from other sites.
Response to Issue 5:
As discussed in the responses to Issues 1 and 3 in this section, if the impoundment is undergoing
closure, Subpart W does not apply to the use of that impoundment for management of closure
wastes. An impoundment that was already subject to Subpart W and is still in operating status
continues to be subject to Subpart W, even if it is accepting wastes generated during closure
activities for another impoundment or portion of the site. The Agency has no plans to change this
position.
New impoundments constructed while the facility is being closed, according to the approved
facility closure plan and for the sole purpose of managing closure or remediation wastes would
not be subject to Subpart W, because they were only constructed to address closure activities.
Subpart T is relevant here: "A pile cannot be considered operational if it is filled to capacity or
the mill it accepts tailings from has been dismantled or otherwise decommissioned" (40 CFR
61.221(b)). Note that the construction requirements in 40 CFR 192.32(a)(1) still apply to these
closure-only impoundments, to the extent that it is managing material covered under UMTRCA.
Regardless of the source of the waste, if the impoundment is accepting uranium byproduct
Final
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EPA 402-R-l 6-004
NESHAPS Subpart WResponse to Comments
material or tailings, and is not being managed under a closure plan, it would be subject to
Subpart W. We note that waste from conventional uranium mines (open pit or underground)
would not be considered uranium byproduct material or tailings because it does not result from
the concentration or extraction of uranium from ore processed primarily for its source material
content.
Issue 6: Operations as it involves placement of tailings from process operations, or use
for evaporative or holding purposes
Summary of Comments Under Issue 6:
A few commenters took the opposite view of that addressed under Issue 1 in this section
(0154/0170, 0172.2, 0172.4). These commenters wish us to clarify that the period of operations
for either a conventional or non-conventional impoundment only extends to the management of
uranium byproduct material produced by the concentration or extraction of ore processed
primarily for its source material content (which may include the commercial management of
such wastes produced at other facilities), and not to the management of wastes (byproduct
material or otherwise) generated during closure or decommissioning activities. Commenter 0188
points out that some closure activities, such as application of a partial cover, may take place
while the impoundment is still operating, before it formally enters the closure process.
Response to Issue 6:
See Section IV.F.2 of the preamble to the final rule for responses to this issue. See also Issues 1
and 3 of this section. Commenter 0188 is correct that a licensee need not wait until the entire
impoundment is full to implement some closure activities, if that is compatible with continued
operation.
Issue 7: Implications of existing and proposed definitions
Summary of Comments Under Issue 7:
We received a number of comments regarding the existing and proposed definitions, some of
which we find useful and others that seem contradictory or not well supported. Several
commenters (0154/0170, 0159, 0162, 0169) viewed the proposed definition as extending the
jurisdiction of Subpart W throughout the closure process. Commenter 0169 states that EPA has
no authority under the Clean Air Act to determine which facilities are "operating," "active," or
"inactive," and that this authority lies solely with NRC.
Commenter 0154/0170 provided extensive comments on the proposed definitions, as well as
suggestions for others. These comments include:
• explicitly address both conventional and non-conventional impoundments in the
definitions;
• clarify the definition of "operations" by replacing the phrase "final closure begins" with
"the closure period for the impoundment begins";
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NESHAPS Subpart WResponse to Comments
• modify the proposed definition of "standby";
• add a definition of "closure period" that starts with notification that an impoundment is
no longer used for its operational purpose; and
• add a definition of "tailings".
Commenter 0186 similarly recommends adding a definition of "closure period" specifying that
the closure period cannot begin until a closure plan is approved and incorporated into the facility
license. The commenter also proposes adopting the definitions in 40 CFR part 192 for "closure
plan," "tailings closure plan (radon)," and "milestone."
Several commenters stated that definitions in or proposed for Subpart W are inconsistent with
NRC's definitions in 10 CFR part 40 (and Appendix A) (Commenters 0154/0170, 0159, 0162,
0165, 0169, 0172.2). For example, Commenters 0159 and 0162 state that "[t]he definition of
Operation conflicts with existing regulations, specifically those in 10 CFR part 40 Appendix A
following the rescission of 40 CFR part 61 Subpart T." These commenters also suggest that we
look to the Appendix A definition of "closure" and they note that the closure period is tied to the
"end of milling operations" in Criterion 6.
Commenter 0153 requests clarification of the term "day that final closure begins," which the
commenter believes has never been adequately explained. Commenter 0172.14 requests
clarification on the steps that must take place for closure to begin.
Response to Issue 7:
See Section IV.F.2 of the preamble to the final rule for responses to comments related to the
definition of "operation" as it relates to the jurisdiction of Subpart W, consistency with NRC
definitions, and closure, including the phrase "final closure." See also Issue 1 in this section. See
Section IV.A.2 of the preamble to the final rule for responses to comments on EPA's authority to
define these terms under Subpart W.
In addition to comments addressed in Section IV.F.2 of the preamble to the final rule,
Commenter 0154/0170 also had several suggestions for definitions that we are not adopting. The
commenter suggests that the definition of "operations" could be further clarified by replacing the
phrase "final closure begins" with "the closure period for the impoundment begins." The
commenter also suggests modification to the proposed definition of "standby." The commenter
also proposed that we add a definition of "tailings" as a further means to distinguish from non-
tailings byproduct material. We do not see the need to do this. We did not propose to change the
definition of "uranium byproduct material or tailings," and are retaining that definition in the
final rule (see Section 2 of this document). We do find it interesting that the same commenter has
stated the view that the Clean Air Act does not give EPA the authority to define UMTRCA-
related terms differently from the way they are defined either in that statute or by NRC. The
definition of "tailings" proposed by the commenter is not the same as that in Section 101(8) of
UMTRCA, nor does it appear that NRC has separately defined "tailings" in 10 CFR part 40.
In response to Commenter 0186, the definition of "final closure" adopted in the final rule
requires the notification to affirm that an approved reclamation plan, with requirements and
milestones, is being implemented. The EPA does not approve reclamation or closure plans, and
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we do not believe it is necessary to require that plan to be incorporated into the facility license.
The final rule adopts a definition of "reclamation plan" that is consistent with NRC's definition
in 10 CFR part 40, Appendix A. Appendix A also contains a definition of "milestone." These
definitions are consistent with those in 40 CFR part 192.
Issue tending operations through final closure as it affects actual facility operations
Summary of Comments Under Issue 8:
Commenter 0154/0170 disagreed with comments presented under Issue 1 of this section and
pointed out that maintaining impoundments under Subpart W jurisdiction while they are
undergoing closure may cause facilities to be out of compliance with the restriction on the
number of conventional impoundments. The commenter posits that this situation could arise if a
facility opened a new conventional impoundment for operational byproduct material, while
having another one in operation and one in closure (or multiple impoundments in closure). To
avoid compliance issues, the commenter explained that facilities may have to defer opening new
impoundments, which could lead to temporary shutdown of the facility's processing operations if
there is no outlet for the wastes. The commenter specifically notes that non-conventional
impoundments may continue in operation when conventional impoundments are in closure.
Commenter 0188 agrees with Commenter 0154/0170. The commenter further believes that
changing the definition in Subpart W would also require changes to the definition in 40 CFR part
192. The commenter sees the lack of an emission standard during closure activities as an
underlying problem that would not be addressed by changing the definition of "operation."
Response to Issue 8:
See Section IV.F.2 of the preamble to the final rule for responses to this issue. See also Issue 1 of
this section. See also Section 6 of this document for responses to comments related to the
operation of non-conventional impoundments. The need for standards to apply during closure is
not within the scope of this rulemaking.
Final
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Sed i • f i 1111 - Eliminating ' \ P • i • • i n if tied by the Nucle. • r l • hi ¦ if-r >
Commission"
Section 10 - Eliminating "As Determined by the Nuclear Regulatory Commission" 52
Issue 1: Potential for EPA's proposal to create dual regulation 53
Issue 2: Record-keeping and reporting requirements 54
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Issue tential for EPA's proposal to create dual regulation
Summary of Comments Under Issue 1:
Many commenters objected to the proposal to eliminate the phrase "as determined by the
Nuclear Regulatory Commission" from provisions related to review of the impoundment
construction requirements in 40 CFR 192.32(a)(1) (Commenters 0144, 0151, 0154/0170, 0159,
0162, 0165, 0169, 0172.2, 0172.5, 0172.6, 0173.1, 0173.10). Commenters in general argued that
this would result in unnecessary dual regulation if both EPA and NRC need to review and
approve construction applications, with limited if any benefit. Commenter 0144 suggests this
will have significant cost implications that were not considered during the rulemaking.
Commenter 0151 questions how disagreements between the agencies will be resolved, and
suggests that appeals will be "inappropriately complicated".
A number of these commenters asserted that our proposal was contrary to the legal framework
established by Congress for management of byproduct material as defined in Section 1 le.(2) of
the Atomic Energy Act (AEA). Commenters cite to the framework in Section 275 of the AEA,
which directs the EPA to establish standards for management of byproduct material and which
gives the NRC sole authority over implementation and enforcement of EPA's standards through
its licensing process (Commenter 0151 cites Title 42 of the United States Code, Section 2022(d)
rather than Section 275 of the AEA). Commenters 0154/0170, 0159 and 0173.10 refer
specifically to that section's statement that "no permit issued by the Administrator is
required.. .for the processing, possession, transfer, or disposal of byproduct material, as defined
in section 1 le.(2) to this subsection." Commenter 0172.6 suggests that EPA is attempting to
expand its role by improperly assuming or duplicating NRC's responsibilities.
Commenter 0169 does not make these specific statutory references, but more generally criticizes
EPA for "grossly inefficient, dual regulation" that is "inconsistent with efficient regulatory
practices" and goes against previous efforts by the two agencies to avoid such situations, as
illustrated by EPA's rescission of subparts I and T. The commenter suggests that Subpart W
could also be rescinded, and notes that EPA's separate rulemaking related to 40 CFR part 192
may be used to incorporate elements of Subpart W as needed.
We also received some comment in support of the proposal to remove the phrase "as determined
by the Nuclear Regulatory Commission" (Commenters 0166, 0173.3, 0173.11, 0172.8).
Commenter 0166 believes this is a welcome clarification that EPA is administering the NESHAP
program. Commenter 0173.3 notes that it is not unusual for an industry to be regulated under
more than one statute or agency. Commenter 0173.11 points out that this situation has existed for
several decades. Commenter 0172.8 agrees and cites EPA approvals under subpart A, as well as
the division of responsibilities at the state level in Utah as they relate to the White Mesa Mill.
Response to Issue 1:
See the response to this issue in Section IV.F.2 of the preamble to the final rule.
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Issue 2: Record-keeping and reporting requirements
Summary of Comments Under Issue 2:
Several commenters also contend that the proposed record-keeping provisions would constitute
burdensome dual regulation (Commenters 0154/0170, 0159, 0172.6, 0173.10). Commenters
0159, 0172.6 and 0173.10 generally raised this issue of dual regulation. Commenter 0154/0170
raised concerns regarding the proposal to require that facilities maintain records demonstrating
compliance with the requirements of 40 CFR 192.32(a)(1), which the commenter sees as the
purview of the NRC or Agreement State.
Commenter 0166 supports the proposed requirement to maintain records of impoundment design
and construction. Commenter 0153 believes records required under Subpart W must be available
to the public, and not only retained by the facilities, and also states that the final rule must
include a schedule for submittal of these records. Commenter 0155 believes clear recordkeeping
and compliance demonstrations are necessary for the "new, more complicated set of bifurcated
work practice standards for conventional and non-conventional impoundments."
Response to Issue 2:
We proposed three specific requirements for records to be maintained by the facility:
demonstration of compliance with the requirements of 40 CFR 192.32(a)(1); documentation that
one meter of liquid is maintained in non-conventional impoundments; and documentation that
heap leach piles are maintained at 30% moisture content. The final rule includes requirements to
maintain records related to compliance with 40 CFR 192.32(a)(1), as well as documentation that
solids in non-conventional impoundments are maintained in a saturated state, which can be
demonstrated by visual evidence that solids are not visible above the liquid surface. Specifically,
the final rule requires that digital photographs documenting the liquid level in non-conventional
impoundments be collected at least weekly and uploaded to a designated reporting system at
least monthly. These photographic records will be made available to the public. The final rule
does not include records related to heap leach piles. We believe these record-keeping
requirements are appropriate for Subpart W, are not burdensome to licensees, and are within our
authority under the Clean Air Act.
Final
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Sedi' ii II I -¦ 'i i .h ! ll ofioitnie; I impact Analysis Issues
Section 11 - Cost and Economic Impact Analysis Issues 55
Issue 1: General cost and economic comments 56
Issue 2: Costs related to water use 57
Issue 3: Costs associated with impoundment design and construction 57
Issue 4: Environmental cost of not monitoring emissions 58
Issue 5: Adequacy of EPA's cost analysis of GACT 59
Final
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Issue 1: General cost and economic comments
Summary of Comments Under Issue 1:
Commenter 0114 believes our proposal will negatively impact the uranium recovery companies,
as well as the national and global economies. The commenter believes we do not have sufficient
justification for the proposed changes. Commenter 0173.1 takes a similar view and believes we
may be underestimating the impacts of the rule on ISL facilities. Commenter 0154/0170
disagrees with our statement related to Executive Order 13211 ("Actions Concerning
Regulations that Significantly Affect Energy Supply, Distribution or Use"), stating that the
proposed requirements would make certain types of uranium recovery less competitive, and
overall would disadvantage the industry compared to other sources of energy. Commenter
0173.3 disagrees, stating that the uranium industry is not economically viable without
government price supports.
Commenter 0144 disagrees that the trend from conventional milling to in-situ leach (ISL) is
driven by economics. The commenter points out that the baseline cost for a conventional mill is
lower than that for an ISL facility, and that the smaller footprint, as well as other operational
advantages, play an important part in these decisions.
Commenter 0153 questions whether any uranium recovery facilities are owned by small
businesses. The commenter notes that it is not uncommon for companies to be owned by large
multi-national firms. As noted in Issue 4, Commenter 0155 agrees, at least as far as conventional
mills. However, Commenter 0154/0170 recommends that we re-assess the estimated costs for
their impacts on small businesses and provides information to correct our assessment of which
facilities are owned by small entities.
Commenter 0172.1 believes EPA has not fully considered the effects on employment of the
proposed requirements.
Response to Issue 1:
The economic impact analysis has appropriately considered impacts on small businesses,
employment effects, and price of uranium. We disagree with Commenter 0154/0170 regarding
the impacts of the proposed rule on the uranium recovery industry, both in comparison to other
sources of energy and in the relative advantage of certain types of uranium recovery. Indeed, for
the most part these requirements have been in place since 1989. The final rule presents a more
limited impact than the proposal and we reach the same conclusion regarding the Executive
Order. We agree that the uranium recovery industry is sensitive to price fluctuations, as are many
natural resource extraction industries. EPA works to balance the necessary level of public health
and environmental protection with economic impacts.
We also have found that ownership of facilities can be complicated; however, we find that most
of the companies that are operating or in the process of developing facilities do qualify as small
businesses, even with the recent reduction in the Small Business Administration (SBA)
employment threshold for such facilities (from 500 to 250 employees, see 13 CFR 121.201 for
North American Industrial Classification System (NAICS) code 212291, effective February 26,
2016). We appreciate the information provided to correct any errors we made in determining
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which facilities are owned by small businesses. We also appreciate Commenter 0144's
perspective; however, we must point out that Table 4 in the preamble to the proposal, which was
cited by the commenter, does not include capital costs for the processing facilities themselves,
nor does it address the long-term costs that are borne by conventional mills conducting
permanent disposal. These aspects are not affected by this rulemaking.
Issue 2: Costs related to water use
Summary of Comments Under Issue 2:
A number of commenters expressed the view that our proposal would require significantly more
water than current practice (Commenters 0104, 0151, 0154/0170, 0172.2, 0173.10). The
commenters generally refer to the challenges of providing large volumes of water in arid regions.
Commenters 0104, 0172.2, 0154/0170 and 0173.10 discuss the aspects of operation that would
be affected, including drilling additional wells, with associated piping and pumping. The
commenters believe this will affect operations in important ways, assuming that water rights can
even be obtained.
Response to Issue 2:
We thank the commenters for this information. After considering comments, the final rule does
not include a requirement to maintain one meter of liquid in non-conventional impoundments or
a requirement to maintain a 30% moisture content in heap leach piles. Operators will be required
to maintain solids in non-conventional impoundments in a saturated state, such that solid
materials are not visible above the liquid level. This requirement is more compatible with current
operations and will adequately control radon emissions. See Sections 6, 7, and 8 of this
document and Sections IV.D.2 and IV.E.2 of the preamble to the final rule for responses to
comments related to water usage for non-conventional impoundments and heap leach piles.
Issue Si Costs associated with impoundment design, and construction
Summary of Comments Under Issue 3:
Commenter 0107 states that evaporation ponds are typically not designed to a depth that can
easily accommodate an additional one meter of liquid. This will result in significant cost to re-
design the affected impoundments. Commenter 0173.9 agrees and states that EPA should
grandfather such impoundments if it does not remove the requirement from the final rule.
Several commenters state that impoundments used only to manage liquids that have been treated
to meet effluent standards should not be subject to Subpart W (Commenters 0107, 0144,
0154/0170, 0173.4). Commenter 0107 states that such impoundments may not meet the full
requirements of 40 CFR 192.32(a)(1), which will necessitate re-design and construction at
significant cost. Commenter 0144 views the proposed revision of 40 CFR 61.252(b)(1) (to
remove "as determined by the Nuclear Regulatory Commission") as "dual regulation,"
potentially making this situation more likely. Commenter 0154/0170 agrees and suggests
changes to the proposed definitions.
Final
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Commenter 0151 wishes us to clarify that non-conventional impoundments that contained
uranium byproduct material and were constructed before 40 CFR part 192 was promulgated
(October 7, 1983) need not be upgraded to meet those requirements (as conventional
impoundments are not). If that is not the case, the commenter believes the Agency must conduct
a cost-benefit analysis.
Commenter 0154/0170 believes that the proposed requirements for heap leach facilities will lead
to construction of larger holding ponds and process facilities than would otherwise be considered
necessary, leading to less efficient operations. The commenter believes this will disadvantage
heap leach facilities compared to ISL facilities. This may also be necessary at other types of
facilities as well. Commenter 0172.2 agrees.
Response to Issue 3:
After considering comments, the final rule does not include a requirement to maintain one meter
of liquid in non-conventional impoundments or a requirement to maintain a 30% moisture
content in heap leach piles. Operators will be required to maintain solids in non-conventional
impoundments in a saturated state, such that solid materials are not visible above the liquid level.
Heap leach piles themselves are regulated by Subpart W only to the extent that they have
completed processing (i.e., have reached the end of their operational life) and have not yet
entered the closure process. Non-conventional impoundments associated with heap leach piles
are subject to the requirements of Subpart W. See Sections 5, 6, and 7 of this document and
Section IV.E.2 of the preamble to the final rule for responses to comments related to non-
conventional impoundments. See Section 8 of this document and Section IV.D.2 of the preamble
to the final rule for responses to comments related to heap leach piles.
Regarding impoundments used for treated water, Subpart W applies to impoundments that are
managing uranium byproduct material or tailings. If the impoundment does not contain uranium
byproduct material or tailings, it does not fall under Subpart W. We believe this determination is
appropriately made by the NRC or NRC Agreement State, but we have not included specific
provisions of this nature in the final rule. See Sections 1 and 6 of this document and Sections
IV.A.2 and IV.E.2 of the preamble to the final rule for responses to comments related to
impoundments used only to manage liquids that have been treated to meet effluent standards. See
Section 10 of this document and Section IV.F.2 of the preamble to the final rule for responses to
comments related to removal of the phrase "as determined by the Nuclear Regulatory
Commission."
See Section IV.F.2 of the preamble to the final rule for responses to Commenter 0151 regarding
impoundments constructed prior to the promulgation of 40 CFR part 192.
Issue vironmental cost of not monitoring emissions
Summary of Comments Under Issue 4:
Commenter 0153 believes the cost of monitoring is negligible when compared to company
revenues. The commenter believes this must be weighed against the cost of environmental and
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health impacts of not monitoring, which have not been fully examined. However, the commenter
also suggests that EPA has not calculated all of the cost savings that will be accrued if the
monitoring requirement is eliminated. These would include items such as monitoring, reporting,
maintenance, and corrective action. The commenter believes that "many thousands of dollars"
will be saved by "EPA's disregard of the provisions of the CAA."
Response to Issue 4:
After considering information provided by commenters, the radon flux standard and monitoring
requirement for conventional impoundments constructed prior to December 15, 1989 is being
retained. See Section 5 of this document and Section IV.B.3 of the preamble to the final rule for
responses to comments related to the radon flux standard and monitoring requirement.
Issue 5: Adequacy of EPA's cost analysis of GACT
Summary of Comments Under Issue 5:
Commenter 0153 finds that our cost analysis of GACT is not valid because the Administrator has
not determined that an emissions standard is not feasible. The commenter further believes that
our Economic Impact Analysis contains much outdated and incomplete information. The
commenter notes that the cost analysis does not address costs associated with soil or liquid
covers or extreme weather events.
Commenter 0155 similarly finds the analysis lacking. The commenter points to the legislative
history of CAA §112 as intending GACT to apply to "smaller, area sources" where economic
impacts are more important. The commenter does not believe these considerations are relevant to
uranium recovery facilities, when conventional mill owners cannot be considered small
businesses. The commenter further finds that we did not evaluate the cost and economic impact
of all control technologies as a means to identify those for further consideration, only a few pre-
selected technologies. The commenter notes that we considered the cost of eliminating radon
flux monitoring, but did not evaluate the impacts of extending the monitoring to all
impoundments. The commenter cites the cost of monitoring at the White Mesa Mill as
representing a limited impact if extended to all impoundments.
Commenter 0168 believes EPA should require concurrent reclamation of conventional mill sites,
citing studies showing the surety for the White Mesa Mill is only about 20% of the projected
liabilities. The commenter believes disproportionate remediation costs will be borne by
taxpayers, and this was not accounted for in our analysis. The commenter suggests this situation
would be improved by limiting the number of operating non-conventional impoundments.
Response to Issue 5:
The Economic Impact Analysis (EIA) has appropriately considered the aspects cited by
Commenters 0153 and 0155. The EIA evaluates the cost of implementing the GACT
management practices. Soil or water cover is not designated as a component of GACT for
conventional impoundments, but maintaining liquid in non-conventional impoundments is
assessed in the EIA.
Final
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We also disagree with the commenters' interpretations of the Clean Air Act and limitations on
taking a GACT approach. CAA § 112(q)(l) requires EPA to review Subpart W and, if
appropriate, revise it to comply with § 112(d). Provisions related to area sources in § 112(d)(5)
do not reflect the limitations on GACT cited by Commenter 0155, nor do they require an
affirmative finding that an emissions standard is not feasible before establishing GACT, as
suggested by Commenter 0153. Further, review under § 112(q)(l) is limited to the existing
standard, and does not require analyses of control technologies or management practices that are
not within the scope of the current standard. Commenter 0155 is correct that we did not propose
to extend monitoring to all conventional impoundments because we determined that the
management practices finalized as GACT are effective in limiting radon emissions. We proposed
instead to apply the GACT management practices proposed under § 112(d)(5) to impoundments
that had previously been subject to an emissions standard and monitoring requirement. The
emissions standard was initially established because construction of these older impoundments
could not be controlled, as it can be for new impoundments. After evaluating comments, we are
retaining the radon flux standard and monitoring requirement for impoundments in existence on
December 15, 1989. See Section 1 of this document and Section IV.A.2 of the preamble to the
final rule for more detailed responses to comments related to the Clean Air Act and GACT.
In response to Commenter 0168, Subpart W applies to operating structures that manage uranium
byproduct material or tailings. It does not apply to such structures that have entered the closure
process. We understand the commenter's concern that inadequate financial sureties could limit
the ability to conduct full closure and site remediation should the licensee declare bankruptcy.
Similar concerns regarding the potential for multiple unreclaimed conventional impoundments
prompted EPA to establish the limits on size and number of such impoundments in the original
1986 rulemaking, carried through as GACT management practices in the final rule. However, we
do not see a similar potential for licensees to construct multiple non-conventional impoundments
beyond their immediate processing needs, given the cost of constructing such impoundments.
Financial sureties are established by the NRC. Closure and remediation requirements are found
in 40 CFR part 192, implemented by 10 CFR part 40, Appendix A.
Final
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Seel - General Comments
Section 12 - General Comments 61
Issue 1: EPA's rulemaking process 62
Issue 2: EPA's Tribal obligations 63
Issue 3: Data to support the proposed rule 65
Issue 4: Strength of the proposed rule 66
Issue 5: EPA's risk assessment 67
Issue 6: Justification for EPA's rulemaking 70
Issue 7: Technical corrections and suggestions 70
Final
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Issue 1: EPA's rulemaking process
Summary of Comments Under Issue 1:
Several commenters expressed the view that EPA did not follow the required process for a
rulemaking and did not adequately involve stakeholders. Commenter 0155 states that EPA staff
discouraged facility-specific comments, which the commenter believes provide relevant
experience to inform the rulemaking. This commenter and others believe that EPA should
essentially begin the rulemaking process again because of the significant deficiencies they find in
the proposal and supporting information. Commenter 0167 believes this is necessary to satisfy
Clean Air Act mandates, as well as fulfill environmental justice principles and recognize that the
1989 work practice standard have not been effective. Commenter 0153 further suggests that
EPA's proposal was not objective and that the Agency is instead "manipulating the experience of
the implementation and enforcement of Subpart W." Several commenters (0140, 0167, 0172.3,
0173.3, 0173.5) expressed their concern that public hearings were not held in communities closer
to operating facilities, instead of "the industry's headquarters." Commenter 0167 suggests that
EPA has made no effort to address the concerns of these communities.
Response to Issue 1:
We disagree with these comments. Our § 112(q)(l) review addresses the mandates of the Clean
Air Act. EPA's rulemaking process was appropriate and provided opportunity for public
comment. We appreciate additional information provided by commenters, including facility-
specific information, and have considered it in developing the final rule. We recognize that some
aspects of our proposal were based on inaccurate information; however, we disagree that this
necessitates an entirely new rulemaking effort. The fact that we have used information provided
by these commenters in retaining the radon flux standard and monitoring requirement for
conventional impoundments in existence on December 15, 1989 refutes the suggestion that our
decisions were pre-determined. See Section 5 of this document.
We recognize that many stakeholders are not satisfied with the performance of specific facilities
or the enforcement of the requirements of Subpart W. These are matters beyond the scope of this
specific rulemaking, which is to conform Subpart W, as appropriate, to the requirements of CAA
§ 112(d). See Section 1 and Section 13 of this document.
Contrary to the statements of commenters, we made extensive efforts to collect input from
affected stakeholders. In addition to the two public hearings we held in Denver, which is
centrally located from numerous uranium recovery facilities, we solicited comment through
EPA's rulemaking docket at EPA-HQ-OAR-2008-0218. We initially provided a 90-day
comment period; in response to public requests, we extended the comment period by 90 days.
We have also tried to capture community knowledge through the use of informal meetings in
Canon City, CO; Rapid City, SD; Gallup, NM; Tuba City, AZ; and White Mesa, UT. We held an
additional meeting with Canon City stakeholders during a break from the public hearing. We
held a consultation with the Ute Mountain Ute Tribe (see Issue 2 of this section). We also held a
nationwide webinar to collect information. We have held quarterly stakeholder conference calls.
We have diligently provided opportunities for community input.
Final
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Issue I obligations
Summary of Comments Under Issue 2:
Commenters 0131 and 0132 urged the EPA to do more than simply adhere to its legal Tribal
consultation requirements and to integrate recommendations from Tribes impacted by uranium
mill tailings, mining operations into this rule and future rules. Commenter 0155 argued that the
EPA failed to properly exercise its trust responsibility to the Ute Mountain Ute Tribe.
Commenters 0183 and 0184 refer to environmental impacts of the White Mesa facility that affect
the Tribe.
Commenters 0131 and 0132 also challenged the EPA's statement in the Proposed Rule that
Subpart W does "not have tribal implications, as specified in Executive Order (EO) 13175 (65
FR 67249, November 9, 2000)," asserting that that EO 13175 does not require the direct
regulatory requirement be placed on Tribal governments for EO 13175 to be applicable. These
commenters claimed that the EPA should reconsider the applicability of EO 13175 in light of the
historic and ongoing environmental contamination from uranium operations.
Commenter 0155 understands that statutory restrictions and rulemaking processes constrain the
manner in which the EPA undertakes a rulemaking like the revision to Subpart W. However, the
commenter maintains that the EPA must still exercise its trust responsibility to protect human
health and the environment in White Mesa and consult with the Tribe about the Subpart W rule
in a manner that allows the Tribe to give meaningful input into the EPA's rulemaking process.
Commenter 0155 explained that the Ute Mountain Ute Tribe sought to engage with the EPA
because the Tribe's White Mesa community is located less than three miles from the only
operational conventional uranium mill and that the EPA should have held a government-to
government consultation with the Tribe before the Proposed Rule was released for public
comment. Commenter 0155 claims that the EPA violated its trust responsibility and the EPA's
duty to consult with the Tribes by not meaningfully consulting with the Tribe or answer
questions about the rulemaking after repeated consultation requests, and by forcing the Tribe to
give input during a public comment process. Commenter 0132 encouraged the EPA to engage
with Tribes in government-to-government consultation to help insure that any actions proposed
by the EPA do not adversely impact Tribes.
Response to Issue 2:
The EPA recognizes the importance of appropriate consultation with tribes in developing this
rule, consistent with the federal government's trust responsibility to federally recognized tribes.
The EPA's policy is to consult on a government-to-government basis with federally recognized
governments when the EPA's actions and decisions may affect tribal interests. Consultation is a
process of meaningful communication and coordination between the EPA and tribal officials
prior to the EPA taking actions or implementing decisions that may affect tribes. As a process,
consulting includes several methods of interaction that may occur at different levels. The EPA
stands by its trust responsibility to tribes. The EPA is focused on fully implementing Executive
Order 13175, the 1984 Indian Policy for the Administration of Environmental Programs on
Indian Reservations, with an ultimate goal of strengthening the consultation, coordination, and
partnership between tribal governments and the EPA.
Final
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NESHAPS Subpart WResponse to Comments
Subpart W imposes requirements on owners and operators who are licensed to manage uranium
byproduct material at uranium mills, not tribal governments. Therefore, the Subpart W
rulemaking did not trigger our trust responsibility and consultation responsibility under EO
13175. There are no "tribal implications" as that term is used in EO 13175 because Subpart W
does not impose substantial direct compliance costs (or, for that matter, any compliance costs) on
the Tribal governments, and does not preempt Tribal law. Even though Subpart W does not have
tribal implications, as defined by EO 13175, the EPA sought and considered the Tribe's input
through formal consultation and through correspondence throughout the rulemaking process.
Tribes and other stakeholders have had an opportunity to inform the content of the proposed rule
from the very beginning of the drafting process. Prior to releasing the proposed rule, the EPA
held initial meetings with tribes. Since December 2009, the EPA has held quarterly stakeholder
calls to discuss Subpart W. The EPA has sought input from the Ute Mountain Ute Tribe since at
least May 2010 when the EPA visited the Tribe in White Mesa, Utah. The EPA gave a
presentation outlining the process of revising the Subpart W rule. Beginning in 2009, the EPA
held public information meetings regarding Subpart W to facilitate participation and solicit input
from stakeholders, including tribal members, to increase stakeholder awareness and to help
identify issues to be taken into consideration. Meetings were held in Canon City, Colorado (June
2009); Tuba City, Arizona (2009 Uranium Contamination Stakeholder Workshop); Gallup, New
Mexico (2010 Uranium Contamination Stakeholder Workshop); Rapid City, South Dakota
(October 2009, at the Western Mining Action Network); and on the lands of the Ute Mountain
Ute Tribe in White Mesa, Utah (May 2010). The EPA also hosted a national webinar for
interested parties.
The proposed rule was released on May 2, 2014. In June, EPA gave a presentation for the
National Tribal Air Association (NTAA) on the monthly NTAA/EPA policy call. On May 8,
2014, we sent letters to 53 tribal leaders offering consultation on the rule, to ensure tribes had the
opportunity to participate in the process. The Ute Mountain Ute Tribe responded and requested a
formal consultation. The Tribe and the EPA held a formal consultation on July 10, 2014 (Docket
No. EPA-HQ-OAR-2008-0218-0120). Consultation is a process of meaningful communication
and coordination between EPA and tribal officials prior to EPA taking actions or implementing
decisions that may affect tribes. At the formal consultation, at least eight attendees were
associated with the Ute Mountain Ute Tribe and at least twelve participants were associated with
the EPA, including members from EPA Region 8 and from the Office of Radiation and Indoor
Air (ORIA), which is the office within the Office of Air and Radiation that is conducting the
rulemaking. EPA Region 8 personnel attended the consultation at the tribal headquarters in
Towaoc, CO. ORIA personnel were located in Washington, DC.
In advance of the meeting, the Tribe sent the Agency a number of questions regarding the
proposed rule. The questions covered topics including EO 13175, specific analyses of the White
Mesa facility, development of the concept and definitions for non-conventional impoundments
and conventional impoundments and Subpart W's references to 40 CFR part 192. A conference
call was held in advance of the consultation to ensure that the consultation would be as
productive as possible. Over the course of the consultation, the Tribe and the Agency held
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discussions on issues related to the Subpart W rulemaking. The issues centered on radon
emissions from evaporation ponds, liner requirements for conventional mills and potential for
radon emissions in the impoundments during the active life of the impoundments.
In August 2014, the Tribe requested a second consultation. The EPA responded and expressed
our willingness to hold another consultation to discuss public comments received and the
questions the Tribe submitted in advance of the July 2014 consultation. However, the Agency
explained that it would be unable to provide final resolution on these issues until after final rule
publication since the EPA continues to evaluate all comments from all stakeholders throughout
the final rule development process. The EPA remains willing to hold future meetings with the
Tribe regarding Subpart W.
The EPA stands by its trust responsibility and the commitment made in our 1984 Indian Policy to
honor the unique legal and historical relationship between the United States and Indian tribes.
This special government-to-government relationship only functions properly when there is
mutual respect between the sovereigns involved. The EPA appreciates the level of sophistication
with which the Ute Mountain Ute Tribe approached the Subpart W comment process and
consultation.
Issue 3: Data to support the proposed rule
Summary of Comments Under Issue 3:
A number of commenters expressed the view that EPA did not make adequate efforts to collect
available data to support the proposed rule. Commenters pointed to specific data in the
background documents that they believe is incorrect or identify other data they believe was not
considered. Typical concerns were that EPA relied too heavily on "hypothetical models"
(Commenter 0173.6) and not enough on "investigation of conditions on the ground" (Commenter
0167, as well as Commenters 0173.3 and 0173.7). Specific comments related to the Cotter
facility and the failure to conduct required measurements (Commenters 0158 and 0173.5) and the
incorrect data in EPA's record (Commenter 0173.6). Commenter 0167 made similar comments
related to the post-1989 impoundments at the White Mesa Mill. Commenters 0106, 0172.3 and
0185 note that, although EPA sent CAA § 114 letters requesting information on their
impoundments, EPA either did not send the letters to, or receive responses from, certain facilities
(White Mesa, Sweetwater, and Shootaring Canyon). Commenters 0106 and 0185 believe EPA
must pursue that information, through enforcement actions if necessary. Commenter 0153
believes that EPA must investigate all possible methods of monitoring radon emissions in order
to satisfy the CAA mandate to establish emissions standards.
Response to Issue 3:
We disagree with the commenters. EPA investigated conditions "on the ground" by sending
owners or operators of uranium recovery facilities a letter under the authority of the CAA § 114.
These letters, which were sent by EPA's Office of Enforcement and Compliance Assurance
(OECA), required facilities to provide detailed information about the uranium mill and/or in-situ
leaching facility, as well as the number, sizes and types of affected sources (tailings
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impoundments, evaporation ponds and collection ponds) that now or in the past held uranium
byproduct material. We requested information on the history of operation since 1975, ownership
changes, whether the operation was in standby mode and whether plans existed for new facilities
or reactivated operations were expected. We also reviewed the regulatory history of Subpart W
and the radon measurement methods used to determine compliance with the existing standards.
Commenters are correct that we did not send § 114 letters to the Shootaring Canyon and
Sweetwater mills. The letters were only sent to mills that were operating, and those two were on
standby. We appreciate the information provided by commenters to correct the information we
presented on those two mills. It is also correct that we sent two letters in 2009 to Denison Mines,
which owned the White Mesa Mill at the time. The company replied to the initial request for
information as it related to White Mesa. A subsequent request for testing specifically applied to
"in-situ leach and recovery (ISL&R) uranium facilities." The company clarified that it did not
own or operate an ISL at that time.
We disagree with Commenter 0153 regarding the investigation of monitoring methods. We
determined that Method 115 remains appropriate for measuring radon emissions from
conventional impoundments (Docket No. EPA-HQ-OAR-2008-0218-0122). Further, the
commenter is incorrect that the CAA requires us to establish emissions standards for all sources
of radon covered under Subpart W. We did request information on potential methods to monitor
liquid surfaces (non-conventional impoundments), but are not required to do so by the CAA. See
Section 1 of this document for more discussion of legal issues.
Issue eiigtli of the proposed rule
Summary of Comments Under Issue 4:
A number of commenters stated generally that the rule should be strengthened (Commenters
0157, 0158, 0163, 0164, 0167, 0172.14, 0173.3, 0173.6, 0173.11, 0183, 0184). These
commenters express concern that the proposed rule is less stringent than the 1989 rule.
Commenter 0167 views the proposed rule as a "radical and nearly complete departure from the
purpose and structure of the CAA NESHAP program." Commenter 0173.3 states that "open air
processing and disposal" is "absurd" and "dark ages" and should not be considered adequately
protective. Commenters 0173.11 and 0186 suggest that the final rule should place limits on the
length of time a facility can be on standby, citing the Shootaring Canyon mill, which has been on
standby for more than thirty years, as an example. Commenter 0185 believes that the existing
impoundment at Shootaring Canyon would be unable to "receive future tailings from the
processing of ore," so it must be on standby only "to receive over 100,000 tons of material from
the cleanup and reclamation of the old mill and mill site."
Response to Issue 4:
We appreciate the commenters' desire to see a more stringent rule. Information provided in
public comments has led us to retain the radon flux standard and monitoring requirement for
conventional impoundments in existence on December 15, 1989. However, we disagree that the
final rule represents a "radical departure" from the meaning of the CAA. The final rule retains
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both the monitoring requirement for "existing" conventional impoundments and the management
practices, now designated as GACT, for conventional impoundments constructed after December
15, 1989. The final rule also clarifies its application to non-conventional impoundments and heap
leach piles, where there has previously been some confusion. Further, the CAA Amendments of
1990 clearly provide EPA with discretion to promulgate technology-based standards, rather than
emission standards, for area sources. In response to Commenter 0167, the purpose of our review
under CAA § 112(q)(l) was to ensure that Subpart W conforms to the requirements of § 112(d).
In doing so, we did not find it necessary to require industry to adopt wholly new processing
technologies. In response to Commenters 0173.11 and 0186, facilities on standby are required to
renew their licenses during that period. If the NRC or Agreement State believes that
impoundments or heap leach piles managing uranium byproduct material or tailings are not in a
condition to remain in that state safely, they can require the facility to begin closure. Further,
Subpart W applies during standby periods. The Shootaring Canyon and Sweetwater facilities are
required to monitor their impoundments, which were in existence on December 15, 1989. For
impoundments constructed after that date, which are not required to monitor, we encourage NRC
and Agreement States to consider appropriate actions to limit radon emissions during standby
periods. We note that the State of Utah indicates that it would require upgrades to the
impoundment should the Shootaring Canyon mill begin operating again (Docket No. EPA-HQ-
OAR-2008-0218-0151).
Issue k assessment
Summary of Comments Under Issue 5:
Commenters 0158 and 0173.5 criticized EPA's risk assessment on several grounds as it related
to the Cotter mill. The commenters point specifically to the meteorological and population data
used in the modeling, noting that Cotter collects its own meteorological information and that
EPA used the 2000 census instead of the 2010 census. The commenters also believe EPA
misjudged distances to the nearest receptors, based on a draft Public Health Assessment (PHA)
by the Agency for Toxic Substances and Disease Registry (ATSDR) and suggest this could
easily be seen on Google Earth. These commenters and Commenter 0173.8 also find that the risk
assessment did not incorporate available radium and radon data from the site, or note other
sources of radon. The commenters note that site personnel state that EPA did not contact them to
obtain the appropriate information.
Response to Issue 5:
EPA disagrees with the commenters and does not believe the issues raised by the commenters
significantly affect the risk assessment (Docket No. EPA-HQ-OAR-2008-0078). EPA contacted
the Cotter facility in early 2011 to request information from the site, specifically including the
meteorological information. EPA's contractor, SC&A, Inc., sent an email on February 14, 2011,
noting that Cotter had indicated it was willing to share meteorological data and requesting any
other information, such as radon release estimates, that would improve the risk assessment.
SC&A spoke to a facility representative on February 23 and followed up with an email the same
day. On March 8, 2011, the facility representative responded that no information would be
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forthcoming, and specifically referenced an open literature report already identified by SC&A
for the meteorologic information. See Docket No. EPA-HQ-OAR-2008-0218-0192. The Cotter
site is no longer subject to Subpart W because it is undergoing decommissioning and remediation
as a Superfund site.
Regarding the population figures, prior to being used in the risk assessment, the Census Bureau
data must be processed through a program called SecPop, which was developed by Sandia
National Laboratory. The processing is necessary to convert the Census Bureau census tract data
into the 0 to 50 mile population surrounding Cotter, or any other site. In order to utilize the 2010
Census Bureau data in the risk assessment, it is first necessary to revise SecPop to include the
2010 data. On October 21, 2013, Sandia National Laboratory released SecPop, Version 4.2.0,
which included the Census Bureau 2010 data. Thus, this dataset was not available at the time the
risk assessment was conducted. The 2000 SecPop was adjusted by a factor of 1.04 (4%) to
account for estimated population growth between 2000 and 2010. This estimate is reasonably
consistent with actual population growth. According to the Census Bureau, the population of
Canon City increased from 15,431 in the 2000 Census to 16,400 in the 2010 Census, a growth
rate of slightly more than 6%. The population of Fremont County, where Canon City is located,
increased from 46,145 to 46,824 over the same period, a growth rate of about 1.5%. See
"American FactFinder" at factfinder.census.gov.
ATSDR's 2010 Draft PHA identified the distance from the "restricted area" to the nearest home.
For the risk assessment it was necessary to use the distance from the release point (the
impoundment that is the source of radon) to the nearest home.
Table 15 in the risk assessment shows that within the 2-mile (3.2 km) and 5-mile (8.0 km) radii,
about 1,000 and 22,000 people were estimated, respectively (the commenter stated that there are
6,000 residents to the north and west alone within 2 miles of the facility, and 20,000 within 5
miles). We followed the commenter's suggestion, went to Google Maps, and looked for streets
of residents north of the mill. As the image below shows, within 1.7 to 1.8 miles north of the
mill's impoundment, there are no identifiable streets of residents. West and west-north-west of
the mill (e.g., Eagle Drive, Shiloh Drive) the map shows new developments. Individuals in these
areas were evaluated in the risk assessment (page 21), which found that an individual living 1 to
2 kilometers north of the site was the RMEI (reasonably maximally exposed individual), as
opposed to individuals located to the west or west-north-west of the site. Also, at 22,000, the
total population estimated within a 5-mile radius is slightly greater than the 20,000 people that
the commenter suggests should be used.
The reason for the greater discrepancy in the estimated population within 2 miles is unclear.
Using the commenter's population values, a population density in the 0 to 2 mile zone of about
480 people per square mile was calculated, and in the 2 to 5 mile zone, a density of about 210
people per square mile. As can be seen in the Google image below, there does not appear to be
twice the population density close to the site as there is farther from the site.
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Imagery £2015 Google. M
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NESHAPS Subpart WResponse to Comments
Issue 6: Justification for EPA's rulemaking
Summary of Comments Under Issue 6:
Several commenters questioned the necessity of EPA's rulemaking. Commenters 0172.4 and
0172.10 believe Subpart W represents an example of burdensome dual regulation and highlight
the agreements between EPA and NRC that led EPA to rescind subparts T and I in 1994 and
1995, respectively. Commenters 0162, 0172.1, and 0172.13 find the risks addressed by Subpart
W to be sufficiently low as to not justify Subpart W. Commenter 0172.1 raises the linear no-
threshold (LNT) model, which posits that any radiation exposure carries some risk of health
effects, and that the risk is proportional to the exposure, as "only a construct" that "may or may
not reflect reality." This commenter also suggests that workers who are required to maintain
impoundments may face greater risk of physical injury. Commenter 0172.13 notes that the
original impetus for controlling uranium processing wastes was to protect members of the public
who could come into direct contact with those wastes. Now that a protective regulatory system is
in place, the commenter does not see a need to control individual sources within the fenceline, as
is done by Subpart W. The commenter also notes that the difference in natural background
radiation is far larger than the incremental exposures addressed by Subpart W.
Response to Issue 6:
In 1986 and again in 1989, EPA found the risks from radon emissions from uranium processing
wastes to be sufficiently high as to require controls under the Clean Air Act. The current review
under CAA § 112(q)(l) is being conducted to ensure that Subpart W conforms to the
requirements of § 112(d). The Agency is not re-evaluating the decision to promulgate Subpart
W, nor have we evaluated the potential for rescinding it. The preamble to the final rule discussed
areas where NRC requirements may be relevant to Subpart W. In response to Commenter
0172.1, requirements to maintain impoundments have been in place since the original Subpart W
rulemaking in 1986, and are also found in NRC rules. The merits of the LNT model are not at
issue in this rulemaking.
Issue 7: Technical corrections and suggestions
Summary of Comments Under Issue 7:
A number of commenters offered information to correct or clarify statements in the proposed
rule (Commenters 0144, 0151, 0153, 0154, 0173.2, 0173.2). Commenter 0144 identified several
points for clarification in our discussion of uranium recovery facilities, including their technical
operations and licensing status. Commenter 0151 provided a correction on the operating status of
the Shootaring Canyon mill. Commenter 0153 provides additional information on impoundments
at the White Mesa Mill and on the wastes and other potential sources of radon at the Shootaring
Canyon mill. The commenter also addresses terminology related to license termination and non-
conventional impoundments, as well as regulatory responsibilities. Commenter 0154 offered
several suggestions to address consistency of terminology.
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Response to Issue 7:
We appreciate the commenters providing these suggestions or points of clarification. The
preamble to the final rule does not reproduce the detailed operating descriptions and facility
histories presented in the proposal, which were the subject of comments by Commenters 0144
and 0151. Facility licensing and operating status is updated in the discussion of impacts to small
businesses in Section VI. C of the preamble to the final rule.
Commenter 0154 suggested modifying several definitions to provide consistency in use of the
term "conventional impoundment," but also to address terms in the existing definitions such as
"dewatered," "dried," and "trenches or other disposal areas." The final rule provides more
consistency in use of the term "conventional impoundment" (for example, replacing the term
"tailings impoundment"), but we have not made all the related changes requested by the
commenter. We have not adopted the commenter's other suggestions. We believe the experience
in implementing Subpart W for more than two decades indicates that the potential for confusion
is low.
Commenter 0153 states that we neglected to mention Cells 1 and 2 at the White Mesa Mill,
which are "existing" impoundments for disposal of uranium byproduct material or tailings. We
did not mention Cell 2 because it was taken out of service in 2008, and is no longer operating for
purposes of Subpart W. It is being monitored. We did mention Cell 1 as a pre-1989
impoundment used as an evaporation pond (i.e., as a non-conventional impoundment).
According to Energy Fuels, Cell 1 has only been used to manage liquids, and no solid materials
have been placed in it. Further, in its response to EPA's § 114 letter, Denison Mines (then the
owner of the White Mesa Mill) stated that Cell 1 would not be used for disposal and would be
removed upon closure. Should White Mesa put Cell 1 into use as a conventional impoundment, it
would be subject to the radon flux standard and monitoring requirements.
Commenter 0153 also wishes us to note that most of the material in the conventional
impoundment at Shootaring Canyon consists of "equipment and wastes from the cleanup of the
Hydro-Jet Heap-Leach operation (NRC Docket No. 40-7869)," rather than ore processed at the
mill. The commenter also believes we should recognize that ore and contamination represent
significant additional sources of radon at Shootaring Canyon. We appreciate this information, but
it does not affect the status of the impoundment at the mill. Regardless of the material brought
from outside the mill, the impoundment is considered subject to Subpart W until it enters the
closure process. Subpart W does not address ore, contaminated soils, or other sources of radon.
Finally, Commenter 0153 finds the terminology "non-conventional impoundment" confusing and
suggests we find an alternative. The commenter believes this term gives the misleading
impression that "conventional impoundments" are only at "conventional mills" and "non-
conventional impoundments" must not be at "conventional mills." We disagree. Non-
conventional impoundments may be found at any type of uranium recovery facility, including
conventional mills. We selected this term because these impoundments are, in terms of a
liquid/solid ratio, nearly the complete opposite of "conventional" impoundments.
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Sea - Out of the Scope of the Rulemaking
The comments that have been listed in this section have been categorized as outside of the
general scope of the rulemaking. Many of the comments refer to ongoing enforcement actions or
potential enforcement actions that could be brought by either EPA or a State agency. They have
been defined as out of scope because this rule provides standards for operating uranium recovery
facilities. In many instances EPA has either discussed enforcement issues with various
stakeholders outside of the rulemaking process or we have directed stakeholders to State
agencies that have been authorized to run the Subpart W program in their particular State.
Other comments in this category were listed because they spoke directly to a uranium recovery
facility that is no longer in operation. Subpart W is an operating standard and therefore generally
not applicable to facilities no longer in operation. Additionally, in this final rule we have added
depth to definitions regarding operation and closure so there is no mistake when a facility or unit
is in operation.
Further, some comments called EPA to task for requirements that are specifically the jurisdiction
of the Nuclear Regulatory Commission or an Agreement State. Finally, some comments are
wholly unrelated to EPA's proposed Subpart W rule.
Section 13 - Out of the Scope of the Rulemaking 72
Issue 1: Enforcement 73
Issue 2: Contamination 73
Issue 3: Cotter 74
Issue 4: Monitoring 74
Issue 5: Miscellaneous 74
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Issue 1: Enforcement
Summary of Comments Under Issue 1:
Many commenters referred to situations where enforcement is either taking place or has not been
pursued to the commenters' satisfaction. Commenters 0131 and 0132 refer to civil action taken
by the Grand Canyon Trust against the White Mesa Mill for violations of Subpart W.
Commenters 0153, 0155, 0183 and 0184 also assert that White Mesa is in violation of the limit
on impoundments in Subpart W. Commenters 0131 and 0153 believe the full enforcement record
for the uranium recovery industry should be considered in the Subpart W rulemaking.
Commenter 0150 finds the State of Utah "not well suited to regulate radon emissions." The
commenter believes facilities in violation are "being let off the hook" by our rulemaking.
Commenter 0153 agrees that the state has not enforced violations, and also criticizes EPA.
Commenter 0160 also urges EPA to take a stronger enforcement stance.
Response to Issue 1:
Enforcement issues are not within the scope of this rulemaking. The final rule will clarify some
issues that are cited as grounds for enforcement. We find that Commenter 0131 has not correctly
cited a statement from the proposed rule. The commenter asserts, "EPA states that it evaluated
information, including facility compliance histories, in order to reach the conclusion that the
radon flux standard should be abandoned" (emphasis added). In fact, the statement reads, "We
also reviewed the regulatory history of Subpart W and the radon measurement methods used to
determine compliance with the existing standards" (79 FR 25393, emphases added). We did not
say we had reviewed facility compliance histories. Our proposal did, however, state that we
believed the conventional impoundments in existence on December 15, 1989 could meet the
GACT requirements we proposed for these units, based on their size and construction. After
considering public comments, we find that initial conclusion to be incorrect. Therefore, we are
retaining the radon flux standard and monitoring requirements for those older conventional
impoundments. See Section 5 of this document.
Issue 2: Con.tamin.ation.
Summary of Comments Under Issue 2:
Commenter 0145 refers to the "toxic radioactive legacy" left by uranium mining. Commenter
0164 also cites health impacts in communities near the Monticello mill site. Commenter 0168
also refers to the "toxic legacy of irresponsibly operated and inadequately reclaimed uranium
mills" in Utah and urges EPA to apply stringent regulation to the White Mesa Mill. Commenter
0173.6 cites the Cotter facility as "the prime example of lingering contamination," which
UMTRCA was intended to prevent. Commenter 0161 asks who will maintain the impoundments,
in particular the non-conventional impoundments, after closure if the facility is abandoned.
Commenter 0155 highlights groundwater contamination at the White Mesa Mill and questions
whether impoundments have the liners required by Subpart W.
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Response to Issue 2:
We share the commenters' concern over environmental contamination. However, these
comments do not fall within the scope of the Subpart W rulemaking.
Issue 3: Cotter
Summary of Comments Under Issue 3:
Commenter 0158 describes the failure of Cotter to maintain a water cover on its impoundments,
and the failure of EPA and state regulators to enforce the monitoring requirements. Commenters
0142 and 0173.8 both refer to the method Cotter used to calculate background radon levels at the
perimeter of the facility as inadequate and untested, and assert that both EPA and the state have
been unwilling to examine it. Commenter 0167 also believes EPA has not adequately enforced
requirements at the Cotter facility.
Response to Issue 3:
The Cotter facility is undergoing decommissioning and remediation under Superfund, so is no
longer subject to Subpart W. Whether Cotter maintained its impoundments properly, or federal
and state agencies provided proper oversight of the facility, is outside the scope of the Subpart W
rulemaking.
Issue 4: Monitoring
Summary of Comments Under Issue 4:
Commenter 0153 provided a number of comments related to Method 115, including language to
change and recommendations on what the regulated community should and should not be able to
do.
Response to Issue 4:
Prior to the rulemaking, as we were evaluating regulatory options, we evaluated whether Method
115 remains appropriate for sampling radon emissions from conventional impoundments for
purposes of Subpart W. We determined that it does (Docket No. EPA-HQ-OAR-2008-0218-
0122). We eventually proposed to eliminate monitoring for all impoundments. We therefore did
not propose to modify Method 115 or the guidance associated with its use, and such comments
are not within the scope of the current rulemaking. We requested comment only on potential
methods for monitoring radon emissions from liquid surfaces, for which Method 115 is not
appropriate. After considering public comment, we are retaining the radon flux standard and
monitoring requirements for conventional impoundments in existence on December 15, 1989.
Issue 5: Miscellaneous
Summary of Comments Under Issue 5:
Commenter 0153 believes the NESHAP guidance needs to be updated. Commenter 0153
believes the risk assessment should consider health effects other than cancer. Commenters 0143
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and 0152 recommend ensuring consistency between Subpart W and 40 CFR part 192.
Commenter 0153 expresses concern for manufacturers of radon measurement devices if the
monitoring requirement is eliminated. The same commenter expresses the view that cyclic
economic conditions will never allow the uranium recovery industry to operate profitably,
therefore the facilities should be required to decommission immediately. Commenter 0153
believes EPA must consider newer technologies for extracting uranium, such as borehole mining
or ablation. Commenter 0167 asserts that EPA has not been forthcoming about posting non-
privileged records, as required by the settlement agreement resolving Colorado Citizens Against
Toxic Waste and Rocky Mountain Clean Air Action v. Jackson, Civ. Action No. 08-cv-1787 (D.
Colo.).
Response to Issue 5:
These comments do not address the proposed Subpart W rule and are therefore outside the scope
of the Subpart W rulemaking.
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Appendix A: Indc nenters
(The main Docket Number is EPA-HQ-OAR-2008-0218;
The number in the first column is the item number within the main docket,
e.g., 0099 is actually EPA-HQ-OAR-2008-0099)
Docket Commenter
Number
0099 Sarah Fields, Uranium Watch
0101 Bill Thompson, National Tribal Air Association
0104 Frank Filas, Energy Fuels Resources (USA) Inc.
0105 Sarah Fields
0106 Sarah Fields
0107 John W. Cash, Ur-Energy
0114 Steven Le
0131 Bill Thompson, National Tribal Air Association
0132 Tribal Environmental Policy Center
0140 Jennifer Thurston
0141 Shelley Schneider, Nebraska Department of Environmental Quality
0142 KayM. Hawklee
0143 Johnnie Head and Candace Head-Dylla, Bluewater Valley Downstream Alliance
0144 Richard Blubaugh, Powertech (USA) Inc.
0145 Chri stopher Li sh
0149 Margaret Regan
0150 Kathy Van Dame, Wasatch Clean Air Coalition
0151 Rusty Lundberg, Utah Department of Environmental Quality, Division of
Radiation Control
0152 Earthworks
0153 Sarah Fields, Uranium Watch, also on behalf of Living Rivers, Grand Canyon
Trust, Greenaction for Health and Environmental Justice, Information Network
for Responsible Mining, Advocacy Coalition of Telluride, Clean Water Alliance,
Final
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NESHAPS Subpart WResponse to Comments
Western Nebraska Resources Council, Western Colorado Congress, Sierra Club
Nuclear Free Campaign, and Tallahassee Area Community.
0154 David C. Frydenlund and Frank Fllas, Energy Fuels Resources (USA) Inc.
0155 Celene Hawkins and H. Michael Keller, Ute Mountain Ute Tribe
0156 Jennifer Thurston, Information Network for Responsible Mining (INFORM)
0157 Rein Van West, Western Colorado Congress
0158 Sharyn Cunningham
0159 Jonathan Downing, Wyoming Mining Association
0160 Anonymous
0161 Mary Crowe Costello
0162 Oscar Paulson, Kennecott Uranium Company
0163 Emlyn Drake
0164 Nathan Sosa
0165 Michael Welling, Organization of Agreement States Executive Board
0166 Stephen B. Etsitty, Navaj o Nation Environmental Protection Agency
0167 Travis E. Stills on behalf of Colorado Citizens Against Toxic Waste, Grand
Canyon Trust, and the Rocky Mountain Chapter of Sierra Club
0168 Anne Mariah Tapp, Grand Canyon Trust
0169 Katie Sweeney, National Mining Association
0170 David C. Frydenlund and Frank Fllas, Energy Fuels Resources (USA) Inc.
[identical to 0154]
0172 September 3, 2014, public meeting (Denver, CO)
0172.1 Thomas Johnson
0172.2 Frank Filas, Energy Fuels
0172.3 Sarah Fields, Uranium Watch
0172.4 Anthony Thompson, National Mining Association
0172.5 Christopher Pugsley, National Mining Association
0172.6 Katie Sweeney, National Mining Association
0172.7 Oscar Paulson, Kennecott Mining
Final
II
December 2016
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U.S. Environmental Protection Agency
Office of Radiation and Indoor Air
EPA 402-R-l 6-004
NESHAPS Subpart WResponse to Comments
0172.8 Sarah Fields, Uranium Watch
0172.9 Steve Brown, SENES Consultants
0172.10 Anthony Thompson, National Mining Association
0172.11 Douglas Chambers
0172.12 Kimberly Morrison, Energy Fuels
0172.13 Steve Brown, SENES Consultants
0172.14 Sarah Fields, Uranium Watch
0173 September 4, 2014, public meeting (Denver, CO)
0173.1 Scot Bakken, Energy Fuels
0173.2 Sarah Fields, Uranium Watch
0173.3 Travis Stills, Energy and Conservation Law
0173.4 Richard Blubaugh, Power Tech
0173.5 Sharyn Cunningham, Colorado Citizens Against Toxic Waste
0173.6 KayHawklee
0173.7 Sarah Fields, Uranium Watch
0173.8 Sharyn Cunningham, Colorado Citizens Against Toxic Waste
0173.9 John Cash, Ur-Energy
0173.10 David Frydenlund, Energy Fuels
0173.11 Sarah Fields, Uranium Watch
0183 Phil Pearl
0184 David Erley
0185 Sarah Fields, Uranium Watch,
0186 Sarah Fields, Uranium Watch,
0187 Sarah Fields, Uranium Watch,
0188 Sarah Fields, Uranium Watch,
and
on
behalf of INFORM
and
Living Rivers
and
on
behalf of INFORM
and
Living Rivers
and
on
behalf of INFORM
and
Living Rivers
and
on
behalf of INFORM
and
Living Rivers
Final
III
December 2016
-------
U.S. Environmental Protection Agency
Office of Radiation and Indoor Air
EPA 402-R-l 6-004
NESHAPS Subpart WResponse to Comments
\i'[)endix I . I m "f \ crony tits ari>l H \ -1 tr i :>ns
AEA Atomic Energy Act
ALARA As low as reasonably achievable
ATSDR Agency for Toxic Substances and Disease Registry
BID Background information document
CAA Clean Air Act
CAAA Clean Air Act Amendments of 1990
CCAT Colorado Citizens Against Toxic Waste
CFR Code of Federal Regulations
Ci Curie, a unit of radioactivity equal to the amount of a radioactive isotope
that decays at the rate of 3.7 x io10 disintegrations per second.
DOE U.S. Department of Energy
EIA Economic impact analysis
EO Executive Order
EPA U.S. Environmental Protection Agency
FR Federal Register
GACT Generally Available Control Technology
HAP Hazardous Air Pollutant
ISL In-situ leach uranium recovery, also known as in-situ recovery (ISR)
LAACC Large Area Activated Charcoal Canister
mrem millirem, 1 x 10"3 rem - a unit of radiation exposure
MACT Maximum Achievable Control Technology
MOU Memorandum of Understanding
NESHAP National Emission Standard for Hazardous Air Pollutants
NRC U.S. Nuclear Regulatory Commission
NTAA National Tribal Air Association
OMB Office of Management and Budget
pCi picocurie, 1 x 10"12 curie
Ra-226 Radium-226
Rn-222 Radon-222
Final
IV
December 2016
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U.S. Environmental Protection Agency
Office of Radiation and Indoor Air
EPA 402-R-l 6-004
NESHAPS Subpart WResponse to Comments
Radon flux A term applied to the amount of radon crossing a unit area per unit time,
as in picocuries per square centimeter per second (pCi/m2/sec).
RCRA Resource Conservation and Recovery Act
SC&A S. Cohen & Associates, Inc.
Subpart W National Emission Standards for Radon Emissions from Operating Mill
Tailings at 40 CFR 61.250-61.256
SWIPR Subpart W Impoundment Photographic Reporting
tpy tons per year
U3O8 uranium oxide, also known as "yellowcake"
UMTRCA Uranium Mill Tailings Radiation Control Act of 1978
U.S.C. United States Code
Final
V
December 2016
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