Revision of 40 CFR Part 61 Subp
EPA Subpart W Rulemaking

• Legal Considerations• Scientific/Technical Considerations• Real World Implications
Revision of 40 CFR Part 61 Subp

Legal Considerations
Legal Issues

• EPA has no legal or regulatory bases to 

apply 40 CFR Part 61, Subpart W to evaporation ponds at uranium recovery facilities.

• After 20 years of consistent 

interpretation that Subpart W is only applicable to uranium mill tailings impoundments, EPA is inexplicably asserting that Subpart W applies to evaporation ponds at in-situ recovery and conventional mill tailings facilities. 

• EPA’s position is inconsistent with the 

language and the rulemaking history associated with Subpart W. 

• By its very language, Subpart W only 

applies to active uranium mill tailings impoundments and makes no mention of evaporation ponds

• Specific language in Subpa

references uranium mills aassociated tailings

• EPA regulations discuss 

“piles” 

• Specific examples provide

regulations to which Subpdo not include evaporatio

• Rule specifically discusses 

of water (i.e., such as in evponds) as a reason not to about radon emissions sinminimizes or eliminates e

• In Subpart W rule, EPA n

does not intend to apply expeditious radon cover that derived from Subpato apply to evaporation on top of tailings piles/im
Revision of 40 CFR Part 61 Subp

Technical Considerations
Potential Revisions

Inclusion of Waste Fluid Retention Impoundm• One potential revision is the inclusion of waste fluid retention 

impoundments (evaporation ponds, holding ponds and other limpoundments) not containing uranium mill tailings under 40 CSubpart W

• This is not justified due to the insignificant emissions of radon 

retention impoundments as described in the slides that follow.
Radon Emissions from Tailings Ponds

Doug Chambers SENES Consultants Limited - 2009

• Rn-222 gas exchange via diffusion from surface of small lake has been measure

(Experimental lakes, Ontario).

• The data is shown below:

• These fluxes are very low. • Given the worst case regarding turbulent mixing (50 centimeters) with a Radactivity of the water of 1000 pCi/L the flux is only 1 pCi/m2-sec.• Fluid retention ponds do not present a substantial risk regarding of dose to the general public from radon releases. • Based on the above flux rates, any Radon-222 emanating from fluid retentiobe lost in the natural variability of background.
Radon Flux from Evaporation Ponds

Dr. Kenneth Baker – ERG - 2010• The flux rates for water containing 165 pCi/L Radium-226 were very low as sho

• These fluxes were measured by floating Large Area Activated Charcoal CanisteRadium-226 bearing water in a pond at Homestake’s site North of Milan, New Mecanister is shown below:
Experimental Determination of Radon Fluxes over Wate

National Mining Association (NMA) 2012• Experimental work funded by the National Mining Association (NMA) and cond

Energy Laboratories, Inc. to determine radon fluxes over water in a laboratory conducted.

• Large Area Activated Charcoal Canisters (LAACCs) were floated over water in b

containing activities of Radium-226 and Radon-222 varying from 0 to 20,000 ppCi/L increments.

• A floating Large Area Activated Charcoal Canister (LAACC) as used in the exper

below:
Experimental Determination of Radon Fluxes over Wate

National Mining Association (NMA) 2012 (con’t)• The results are shown below:

Maximum and Minimum Radon-222 Fluxes versus Radium226 Activity

0.002.004.006.008.00

10.0012.0014.00

0 4,580 9,450 13,900 19,200

Radium-226 Activity (pCi/L)

R a d o n - 2 2 2 F lu x ( p C i/ M 2 - s e c ) Maximum Radon-222 Flux (pCi/M2-sec) Minimum Radon-222 Flux (pCi/M2-sec) 
Experimental Determination of Radon Fluxes over Wate

National Mining Association (NMA) 2012 (con’t)

Maximum and Minimum Radon-222 Fluxes versus 

Radon-222 Activity

0.002.004.006.008.00

10.0012.0014.00

32 5500 11000 16600 21500

Radon-222 Activity (pCi/L)

Radon-222 Flux (pCi/M2-sec) Maximum Radon-222 Flux (pCi/

sec) Minimum Radon-222 Flux (pci/sec)
Experimental Determination of Radon Fluxes over Wate

National Mining Association (NMA) 2012 (con’t)• Radon flux rates are low even at relatively high Radium-226 and Radon-222 ac

water.

• Radon flux rates in pCi/m2-sec were approximately 0.0004 times the Radium-2

222 activity of the water.

• At a Radium-226/Radon-222 activity of 5,000 pCi/L radon fluxes ranged from 1

pCi/m2-sec.

• According to NUREG-1910 - Generic Environmental Impact Statement for In-Sit

Uranium Milling Facilities – May -2009 over 96.9% of the liquid wastes at in-situranium recovery operations are restoration wastes with Radium-226 activitiepicoCuries per liter.

• This is vastly lower than 5,000 pCi/L and would yield proportionately lower flux

for all intents and purposes be insignificant.
Determination of Radon-222 Fluxes from Fluid Filled L

Kennecott Uranium Company 2010• Kennecott Uranium Company conducted experiments using floating Large Area 

Charcoal Canister (LAACC) units to determine radon fluxes from the lagoons. 

• Floating Large Area Activated Charcoal Canisters (LAACCs) are depicted below:
Determination of Radon-222 Fluxes from Fluid Filled Lagoons – Kennecot

Company 2010

Pool

Radium-226

Activity 

Radon-222

Activity in

LAAC

Number Placed Retrieved Charc

Name Fluid Fluid Date Time Date Time Moist

(pCi/L) (pCi/L) (Perce

1-E 26 570 116 8/10/2010 11:24 8/11/2010 12:53 1-E 26 570 117 8/10/2010 11:27 8/11/2010 12:54 1-E 26 570 1 8/11/2010 12:53 8/12/2010 13:18 1-E 26 570 2 8/11/2010 12:54 8/12/2010 13:18 5-E 39 1750 118 8/10/2010 11:33 8/11/2010 12:57 5-E 39 1750 119 8/10/2010 11:37 8/11/2010 12:58 5-E 39 1750 3 8/11/2010 12:57 8/12/2010 13:20 5-E 39 1750 4 8/11/2010 12:58 8/12/2010 13:22 9-W 22 772 120 8/10/2010 11:43 8/11/2010 13:01 9-W 22 772 121 8/10/2010 11:49 8/11/2010 13:03 9-W 22 772 122 8/10/2010 11:53 8/11/2010 13:04 9-W 22 772 5 8/11/2010 13:01 8/12/2010 13:25 9-W 22 772 6 8/11/2010 13:03 8/12/2010 13:27 9-W 22 772 7 8/11/2010 13:04 8/12/2010 13:27 SE Pool 15 446 123 8/10/2010 12:00 8/11/2010 13:09 SE Pool 15 446 124 8/10/2010 12:03 8/11/2010 13:11 SE Pool 15 446 125 8/10/2010 12:07 8/11/2010 13:12 SE Pool 15 446 8 8/11/2010 13:09 8/12/2010 13:32 SE Pool 15 446 9 8/11/2010 13:11 8/12/2010 13:34 SE Pool 15 446 10 8/11/2010 13:12 8/12/2010 13:33 
Determination of Radon-222 Fluxes from Fluid 

Lagoons – Kennecott Uranium Company 2010 

• Radon fluxes from these ponds were very low.• In no case did a radon flux measurement exceed 1.0 pCi/m2-sec.

• These fluxes do not exceed and are indistinguishable from natural ba
Risks Related to Radon from Uranium Rec

• The following three (3) papers discuss epidemiology in three (3) uranium producing areas 

Texas; Montrose County, Colorado and the Grants Area in New Mexico:

• Cancer Mortality in a Texas County with Prior Uranium Mining and Milling Activities 

(Boice, J.D. Jr. et al September 8, 2003)

• Cancer and Noncancer Mortality in Persons Living near Uranium and Vanadium Min

Operations in Montrose County, Colorado 1950 – 2000 (Boice, J.D. Jr. et al 2007)

• A cohort study of uranium millers and miners of Grants, New Mexico, 1979–2005 dat

2008

• Cancer Mortality in a Texas County with Prior Uranium Mining and Milling Activities 1950 

J.D. Jr. et al September 8, 2003) concludes:

• Overall, 1223 cancer deaths occurred in the population residing in Karnes 

1950 to 2001 compared with 1392 expected based on general population US. There were 3857 cancer deaths in the four control counties during the 

period compared with4389 expected. There was no difference between th

mortality rates in KarnesCounty and those in the control counties (RR = 1.0confidence interval 0.9–1.1). There were no significant increases in Karnes any cancer when comparisons were made with either the US population, tTexas or the control counties.
Risks Related to Radon from Uranium Rec

(con’t)• Cancer and Noncancer Mortality in Persons Living near Uranium and Vanadium Mining an

Operations in Montrose County, Colorado 1950 – 2000 (Boice, J.D. Jr. et al 2007) conclude

• Between 1950 and 2000 a total of 1,877 cancer deaths occurred in the population re

Montrose County, compared with 1,903 expected based on general population rates (SMRCO 0.99). There were 11,837 cancer deaths in the five comparison counties duryear period compared with 12,135 expected (SMRCO 0.98). These was no difference total cancer mortality rates in Montrose county and those in the comparison countieCI 0.96-1.06).

• A cohort study of uranium millers and miners of Grants, New Mexico, 1979–2005 dated A

concludes:

• No statistically significant elevation in any cause of death was seen among 

miners employed at the Grants uranium mill. Among 718 mill workers wit

potential for exposure to uranium ore, no statistically significant increase 

death of a priori interest was seen, i.e., cancers of the lung, kidney, liver, olymphoma, non-malignant respiratory disease, renal disease or liver diseathe population studied was relatively small, the follow-up was long (up to complete.

• Three epidemiological studies show no risks to maximally exposed population 

specifically those living in areas hosting uranium processing.
Revision of 40 CFR Part 61 Subp

Real World Implications
Real World Implications

• Regulation of fluid retention impoundments under Subpart W will 

uranium recovery operations

• To operate, both conventional mills and in-situ recovery facilities can r

areas of evaporation ponds

• Inclusion of evaporation ponds within existing area limitations would 

operations and prevent new ones from starting.

• It would force current and future operators to consider alternate met

handling fluids such as deep well injection which may not be approved current or planned operations. Even if approved, these alternate metcost prohibitive. 

• Conflicts with existing approvals

• Example: Kennecott Uranium has a license amendment in place allowing 

second (40 acre) tailings impoundment plus eight 10-acre evaporation pon

• Regulation of evaporation ponds under 40 CFR Part 61 Subpart W and inclusio

the maximum allowable area would interfere with previously reviewed and apThese approved plans have undergone NEPA review.
Real World Implications (con’t)

• Alternatives to evaporation ponds may be in certain circumstan

desirable from an environmental perspective than evaporation 

• Evaporation ponds are a proven, environmentally sound metho

managing wastewater especially in the arid West where most production occurs.

• Uranium recovery operations both conventional and in-situ, re

environmentally sound, proven and cost effective means to hastore wastewater even where final disposition (deep disposal omay be utilized. Evaporation ponds fill those requirements.

• Regulation of evaporation ponds and fluid retention impoundm

40 CFR Part 61 Subpart W will severely constrain existing operaproposed ones, in some cases halting them. This is poor policy the very small risk and the need for domestically produced urapower this nation’s reactors.