FAQs & Fact Sheets:Public Health & Environment

Environmental and Public Safety During In-Situ Uranium Recovery

Regulatory agencies that oversee in-situ recovery (ISR) operations:

The U.S. Nuclear Regulatory Commission (NRC) and the United States Environmental Protection Agency oversee and regulate the process of in-situ uranium recovery throughout all areas that are productive for ISR uranium. In South Dakota, for Azarga’s Dewey Burdock property, the NRC is the coordinating agency. However, Colorado is an ‘Agreement State,’ meaning that the Colorado Department of Public Health and Environment (CDPHE) has entered into an agreement with NRC to oversee all uranium licensing on NRC’s behalf. Source Material & By-Product Licenses are issued by the CDPHE’s Radiation Program of the Hazardous Materials and Waste Management Division. However, the other Divisions of CDPHE and the Department of Natural Resources Mined Land Reclamation Board as well as local county agencies will have active rolls in the review of an application for license. In all provinces where uranium is, or has been, mined, the different agencies work closely together and have a strong record of reviewing radiation matters and licensing. The effect of this responsibility is that the local, state and federal personnel review all applications and oversee all ISR operations to insure that all regulatory requirements are met. In addition to the NRC and CDPHE, the EPA, Region 8, located in Denver, also has an active role in the permitting process because the EPA is the issuing agency for the Underground Injection Control (UIC) Permit and aquifer exemption which are required for ISR mining under the Safe Drinking Water Act.

The supervising agencies also ensure that the areas adjacent to and surrounding the permitted operating areas will remain safe for all activities and residents, just as they are today. The suspension of any activities by the landowner is only within the operating area, where the drilling rigs, vehicles, wells, monitoring equipment and backhoes are treated as industrial equipment and restricted to qualified personnel only for the safety reasons just like any industrial site.

In addition to the normal licensing and permitting review, the Nuclear Regulatory Commission limits radiation exposure for any member of the public from a uranium extraction facility at 25 millirems per year, with a condition that exposure be as low as reasonably possible. While any exposure to radiation can seem frightening, consider this limit in perspective. It is one-sixteenth of the average amount of radiation (400 millirems) that a person in the Rocky Mountain Region receives each year from natural sources alone. Further, under the NRC’s direction all companies are mandated to maintain exposures below this limit and will follow other requirements issued by regulatory agencies.

Radiation Risk in Perspective

Radiation is everywhere. Radiation is energy. There are two forms of radiation: non-ionizing radiation and ionizing. Non-ionizing radiation includes television and radio signals and does the cooking in your microwave. Ionizing radiation emanates from radioactive material, X-ray machines and cosmic rays. For this discussion, radiation refers to the ionizing type only.

There are two types of ionizing radiation: manmade and naturally occurring. Manmade radiation originates from X-ray machines, the nuclear fuel cycle and remnants of radioactive material fallout. Naturally occurring radiation originates from terrestrial sources of radioactive materials and the cosmic ray background.

For this discussion the unit of radiation measurement is the millirem (mrem), or one thousandth of a rem. The US Nuclear Regulatory Commission (NRC) set the occupational limit at 5,000 mrem per year and the non-occupational limit at 100 mrem per year. For an In Situ Recovery (ISR) uranium mine, the maximum allowable NRC limit to a member of the public is 25 mrem per year. All of these limits are in addition to background levels.

Natural Background Radiation Exposure in Colorado Compared to U.S Averages Units of mrem / yr effective dose equivalent
Source U.S Avg.1 Colorado Avg. 2 Leadville 2
Cosmic Radiation 27 50 85
Terrestrial Radiation 28 49 97
Inhaled Radon and its
decay products
200 301 344
1 Idaho State University, “Radiation Risks in Perspective”, http://www.physics.isu.edu/radinf/risk.htm
2 Moeller, D. and Sun, L.S.C, ” Comparison of Natural Background Dose Rates For Residents of The Amargosa Valley,N.V., To Those In Leadville, Co. and the States of Colorado and Nevada”, Health Physics, October, 2006

The average background radiation exposure in America is approximately 360 mrem per year. About 300 mrem per year originates from natural background sources, with two-thirds of this dose from radon; and the manmade exposures are primarily from medical uses.


Direct gamma rays originating from naturally occurring radioactive elements and cosmic radiation comprise about one third of the average US natural background exposure. This radiation is easily measured and is greater in areas of rocky outcrops and higher elevation than lower elevation areas with substantial overburden covering any rock layers.

For this discussion we’ll call this direct natural background radiation (DNBR) because it is easily measured with a handheld meter such as a scintilometer. The US average DNBR, is about 255 mrem/yr, or about 2.5 times the maximum allowable dose from an NRC-licensed ISR uranium mine (100 mrem/yr). The DNBR for Colorado is about 400 mrem per year – or 4 times the maximum allowable dose. The DNBR for Nunn, CO would be approximately the same