U.S. EPA Regulations Review Update: 

Subpart W NESHAPS (40 CFR 61)

Reid J. Rosnick

Radiation Protection Division

U.S. Environmental Protection Agency

National Tribal Air Association

NTAA-EPA Air Policy Call 

June 26th, 2014
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Review of 40 CFR 61 Subpart W

 National Emission Standard for Hazardous Air 

Pollutants (NESHAP) for radon emissions for 

operating mill tailings

 Review began after receiving Notice of Intent to 

Sue (NOI) by two Colorado environmental 

groups

 Based on EPA’s alleged failure to review & revise 

regulation within ten years after enactment of Clean 

Air Act Amendments of 1990 (11/15/2000)

 Plaintiffs filed suit against EPA 

 Settlement agreement reached November 2009
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Existing Subpart W Summary

 Applies to radon emissions from operating 

uranium mill tailings

 Radon emissions flux standard: 20 pCi/m2/sec

 After 12/15/1989, new impoundments were 

required to meet one of two new work practices:

 Phased disposal – Impoundment size(2) < 40 acres

 Continuous disposal – dewatered tailings with no more 

than 10 acres uncovered

 Both must meet design, construction, ground-water 

monitoring standards at 40 CFR 192.32(a)

 Work practices were designed to achieve at least 

equivalent risk reductions as obtained by the 

numerical standard

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Existing Subpart W, continued

 Regulation originally written with emphasis on 

conventional impoundments

 In Situ Leach/Recovery (ISL/ISR) extraction has 

become more commonplace since original 

promulgation

 Does not generate significant tailings

 Wastes containing uranium byproduct material are 

placed in evaporation ponds/impoundments

 ISL/ISR, conventional mill, heap leach operations 

expected

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Proposed Subpart W Revisions

 EPA is proposing several revisions (under 

authority of the Clean Air Act Amendments of 

1990):

 Clearly stating that the standards apply to all units 

that contain uranium byproduct material. These units 

include, but are not limited to:

 conventional tailings impoundments

 evaporation ponds or other nonconventional 

impoundments at uranium recovery facilities

 heap leach piles

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Proposed Subpart W Revisions, cont.

 Propose that all uranium recovery facilities 

comply with Generally Available Control 

Technology (GACT), or management practices

 Management practices incorporate existing “work 

practices” for conventional impoundments

 Management practices also specified for evaporation 

ponds and heap leach piles

 This standard requires double liners and leak detection 

systems per 40 CFR 192.32(a)

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Proposed Subpart W Revisions, cont.

 Proposed GACT removes the requirement for 

monitoring radon, but still limits the amount of 

byproduct material that can be exposed 

 For conventional impoundments, limit tailings 

exposure using either phased disposal or continuous 

disposal

 For heap leach piles, limit tailings exposure using 

phased disposal and maintain a 30 % moisture 

content in the pile

 For evaporation ponds, require at least one meter of 

liquid be constantly maintained in the pond

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Proposed Subpart W Revisions, cont.

 Add definitions for:

 uranium recovery facility

 operation and standby

 Conventional impoundment

 non-conventional impoundment

 heap leach pile

 Require the owner/operator of a uranium 

recovery facility to maintain records that 

confirm that impoundments have been 

constructed according to the requirements

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Outreach 

 Presentations made in Gallup, NM, Rapid City, 

SD, Denver, CO, Ute Mountain Ute Recreation 

Center (White Mesa)

 Dedicated website: 

(www.epa.gov/radiation/neshaps/subpartw/rule

making-activity.html

 Quarterly stakeholder conference calls (July 3, 

866-299-3188, code 2023439563#)

 Letters requesting consultation sent to 55 tribes 

 Consultation requested by Ute Mountain Ute

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Comments/Public Hearing

 The proposed rule was published in the Federal 

Register on May 2, 2014 (79 FR 25388)

 EPA will accept comment until July 31, 2014 (90 

days after the proposed rule was published)

 EPA has received requests to extend comment 

period. Extension will be granted - time has not 

been decided

 Public hearing will be held during the comment 

period

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