EPA 40 CFR Part 192 Uranium-Thorium Standards Discussion Forum

As part of its review, EPA is examining the potential environmental, economic, and cultural impacts of uranium facility operations on Tribes and low-income populations.

Since 40 CFR Part 192 was originally issued in 1983, EPA’s has established a Policy for Administration of Environmental Programs on Indian Reservations.

Executive Order 128988 of 1994 directs the Federal government to address environmental health issues in low-income and minority communities.

EPA is also reviewing the impact of uranium facility operation on children.  Executive Order 13045 of 1997 requires the federal government address environmental health risks that disproportionally affect children.

We invite you to provide your thoughts on this topic

Since 40 CFR Part 192 was released in 1983, changes and updates have been made in the underlying science that supports radiation dose and risk assessments for this rule.

Important literature citations about some of these changes include—

• International Commission on Radiological Protection, 2008. “Publication 103 Recommendations of the ICRP, Annals of the ICRP.” Volume 37, Issue 2-4, January 2008.
• National Research Council, 2006. “Health Risks for Exposure to Low Levels of Ionizing Radiation; BEIR VII, Phase II.” Committee to Assess Health Risks from Exposure to Low Levels of Ionizing Radiation, Board on Radiation Effects Research, Division of Earth and Life Sciences.  National Academies Press. Washington, DC 20001.

EPA is reviewing the existing rule to evaluate—

• potential impacts of changes in dose and risk assessment
• additional exposure scenarios
• use of different or updated computer risk models
• models that include distribution of Tribal and environmental justice communities’ population and their usage of land and resources
• impact of climate on exposure from facilities not located in the historic mining areas of the southwestern U.S.

We invite you to provide your thoughts on this topic.

The current primary standard at 40 CFR Part 192 requires restoration of groundwater at mill tailings and extraction sites to either background concentrations or regulatory “Maximum Concentration Limits”, whichever are higher. 

The regulations at 40 CFR Part 192 provide specific maximum concentration limits for specific hazardous constituents that generally correspond to EPA’s Maximum Contaminant Levels (MCLs) which are used for public drinking water supply protection under the Safe Drinking Water Act (40 CFR Parts 141-143).  The current EPA MCLs for silver, lead, uranium and arsenic (metals which are all potentially present in uranium ore zones) have been revised since 40 CFR Part 192 was last updated–

• Silver– The current EPA standard (0.1 milligrams/liter) is a secondary MCL and is less restrictive than the maximum concentration limit value in 40 CFR Part 192 of 0.05 milligrams/liter.  Ingestion of silver, which is commonly found with uranium, can cause the disease argyria, a permanent blue-gray discoloration of the skin, as well as kidney damage.
• Lead—The current MCL for lead in 40 CFR Part 141 is 0.015 milligrams/liter is more restrictive than the maximum concentration limit of 0.05 milligrams/liter in 40 CFR Part 192..  The U.S. Food and Drug Administration requires bottled water for human consumption to meet an even more restrictive standard of 0.005 milligrams/liter or less. Lead is a neurotoxin which can also affect the functioning of the brain and many body organs.
• Uranium—The current MCL for uranium in 40 CFR Part 141 is 0.30 milligrams/liter. The maximum concentration limit in 40 CFR Part 192 is a concentration of 30 pCi/liter of uranium-234 and uranium-238 combined (equivalent to 0.44 milligrams/liter), which is the standard utilized by the NRC in overseeing licensed facilities. Uranium ingestion can cause kidney disease.
• Arsenic—The MCL for arsenic in 40 CFR Part 141 is 0.05 milligrams/liter, while the maximum concentration limit in 40 CFR Part 192 is 0.01 milligrams/liter.  Arsenic is a poison which can damage the skin and cause cancers in multiple body organs.

The Agency will also be examining how the existing standards may be applied to address surface and groundwater protection for ISL/ISR facilities, heap leach facilities, and co-mineral development operations.

The Department of Energy, as well as the Nuclear Regulatory Commission and its Agreement States may permit restoration of groundwater to higher Alternate Concentration Limits (ACLs) provided that the higher concentrations pose no present or potential hazard to human health or the environment.  More than twenty specific requirements must be satisfied to allow the use of ACLs (40 CFR 192.02( c)(3)(i)(C) and   

40 CFR.32(a)(2)(iv)).

During its review of 40 CFR 192, EPA is considering whether to leave the groundwater standards unchanged or revise them.

We invite you to provide your thoughts on this topic

Changes in uranium industry technologies (such as the current use of the In-Situ Leaching (ISL) recovery process as the primary technology for extracting uranium) and their potential environmental impacts.

While 40 CFR Part 192 standards are applicable to any type of uranium or thorium extraction facility licensed by the NRC or its Agreement States, EPA originally wrote its current standards for conventional mills and mill tailings impoundments. Since publication of EPA’s original 40 CFR Part 192 regulations, ISL has become the principal means of uranium recovery in the United States. EPA is reviewing these standards to determine if the requirements are appropriate for ISL recovery, heap leaching, and co-mineral development technologies.

EPA is also evaluating the current standards because of the difference in the management of conventional and ISL facilities after their active lives. Conventional uranium mills and mill tailings impoundments are reclaimed, licensed, and maintained by the Department of Energy (DOE) in perpetuity. ISL recovery, heap-leach, and co-mineral development facilities are released for public and private use after they have been reclaimed.

In addition, we are looking to learn more about the operational history of current and previously licensed facilities.

We invite you to provide your thoughts on this topic.

Available Documents

The Library page provides recent EPA technical reports (2008) that describe activities and methods of uranium mining and milling, the wastes generated, potential human and environmental impacts, and reclamation methods, as well as regulatory and statutory background information. It also provides earlier EPA reports on uranium mining (1983, 1985, 1995), supporting background information documents, environmental regulatory impact documents for the original rule, and later updates of the regulation.

The NRC has published a final generic environmental impact statement for ISL facilities, which can be downloaded at:
ISL milling.