EPA’S

NESHAP Subpart W Activities

Reid J. Rosnick

Environmental Protection Agency

Office of Radiation and Indoor Air

Radiation Protection Division (6608J)

Washington, DC 20460

rosnick.reid@epa.gov

May 27, 2010

Uranium Recovery Workshop 2010
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Overview

EPA regulatory requirements for operating 

uranium mill tailings (Subpart W)

General requirements applicable to Subpart W

Status Update on Subpart W Activities

Communications
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EPA Regulatory Requirements for 

Operating Uranium Mill Tailings (Clean Air Act)

• 40 CFR 61 Subpart W requirements apply to facilities licensed 

to manage uranium byproduct materials during and following 

the processing of uranium ores

• Preconstruction approval, 40 CFR 61.07

• Impoundment construction and operation requirements in 

40 CFR 192 cross referenced in Subpart W 

• Limit on number/size of impoundments

• Phased Disposal – lined impoundments no more than 

40 acres, no more than two in operation at any time

• Continuous Disposal – tailings are dewatered and 

immediately disposed, no more than 10 acres 

uncovered at any time
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EPA Regulatory Requirements for 

Uranium Operations (Clean Air Act)

Subpart W Requirements (continued)

• Radon emission standard of 20 pCi/m2/sec --

annual reporting requirements, notification in 

advance of testing

• The radon emission standard is for existing sources 

only (existing before 12/15/89)

• All operators must comply with 40 CFR 192.32(a) 

See 

http://www.epa.gov/radiation/neshaps/subpartw/rule

making-activity.html for more information
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EPA Regulatory Requirements for 

Underground Uranium Mining (Clean Air Act)

• 40 CFR 61.20, Subpart B regulations limiting radon 

emissions from underground uranium mines include:

• Applies to 10,000 tons/yr ore production, or 100,000 

tons/mine lifetime

• Ambient air radon standard not to exceed 10 mrem/yr 

to any member of the public-compliance determined 

with COMPLY-R, or equivalent, approved code

• Annual reporting requirements – by 3/31 each year, 

emissions calculations for the year, monthly if not in 

compliance

• Record keeping requirements: Five years
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General Requirements Applicable to Subpart W

• Subpart W and B facilities are subject to the general 

requirements of 40 CFR 61.01 - .19

• Application for construction and modification

• Notification of startup

• Compliance with monitoring/maintenance requirements

• Subpart W facilities are subject to the design and 

ground-water requirements of 40 CFR 192.32(a)

• Ground-water protection standards 

• Impoundment design requirements similar to hazardous 

waste facilities
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•Status Update on Subpart W Activities
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Status of Subpart W Review Activities

• Major emphasis on risk assessments

• Purpose is to update risk numbers used in 1989 

rulemaking to reflect state of the science

• Evaluate impacts to the public

• Also focus on Tribes, EJ communities, children’s health

• All operating tailings piles and ISL’s

• Stylized scenarios will also be developed for 

representative future sites

• Scenarios would include varied climate, heap leach 
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Status of Subpart W Review Activities

Choosing a Risk Assessment Model

• 1989 rule used AIRDOS to calculate dose and risk

• Determination which model is appropriate

• Candidate models include CAP88, GENII, 

RESRAD, MILDOS-AREA, MEPAS, GASPAR

• We welcome any other candidates you may know 

about
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Status of Subpart W Review Activities

• Preliminary screening of candidate codes

• Once defined, the code will be used to determine 

individual and population dose and risk

• Some evaluation criteria include:

• Exposure pathways modeled

• Dose factors used

• Risk factors used

• Source term calculation

• Input parameter sensitivity analysis

• Verification/validation/documentation

• Ease of use/user friendly
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Status of Subpart W Activities

• Risk estimates will be developed for each Subpart 

W facility 

• Estimates will be presented on a facility-by-facility 

basis, the same format used in the 1989 rulemaking

• Source category, radionuclides released, existing controls

• Bases for the risk estimate

• Results of the dose and risk calculations

• Description of supplementary emissions controls and cost 

effectiveness in reducing dose and risk
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Communications
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Communications

• We have developed a website dedicated to Subpart 

W which provides internet access to background 

information already compiled by EPA

• Provides public access to all non-privileged records, 

especially technical documents, as well as useful 

links to sites relevant to Subpart W

• http://www.epa.gov/radiation/neshaps/subpartw/rule

making-activity.html
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Communications

• We are conducting quarterly conference calls to 

brief stakeholders on the review of Subpart W

• Next Call is scheduled for Tuesday, July 6, 2010 at 

11:00 AM EDT

• Phone-in number – 1-866-299-3188

• Conference Code 2023439563
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Communications

• In addition to in-person regional presentations such 

as this, we are also holding an internet seminar 

(webinar) 

• Thursday, June 17, 2010 at 11:00 AM, EDT

• Please see the Subpart W website for details on 

how to access the webinar
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Questions?