NORM (Naturally Occurring Radioactive Material)
Karen Diebert, Environmental Scientist
Dale Patrick, MS, Manager
By definition, naturally occurring radioactive material (NORM) is not subject to regulatory control under the Atomic Energy Act of 1954, or the Low Level Radioactive Waste Policy Act. Because of these regulatory exclusions, NORM is subject primarily only to individual state radiation control regulations. In North Dakota, NORM is under the regulatory control of the Radiation Control Program of the North Dakota Department of Health - Division of Air Quality.
Wastes containing NORM are generally
not regulated by federal agencies. One exception is the
transportation of NORM contaminated wastes. These shipments
are subject to U.S. Department of Transportation (DOT)
regulations. In addition, NORM handling and management
activities may be subject to regulations promulgated by the
Occupational Safety & Health Administration (OSHA) as
well as those maintained by the North Dakota Health
Naturally Occurring Radioactive Material (NORM)
Naturally occurring radioactive materials (NORM) generally contain radionuclides found in nature, such as radium, thorium, uranium, etc. Once this NORM becomes concentrated through human activity, such as mineral extraction or oil production, it can become a radioactive contamination hazard or a radioactive waste.
There are two types of NORM material: Discrete and Diffuse.
The first, discrete NORM, has a relatively high radioactivity concentration in a very small volume, such as a radium source used in medical procedures or level gauges. Because of its relatively high concentration of radioactivity, this type of NORM poses a direct radiation exposure hazard.
The second type, diffuse NORM, has a much lower concentration of radioactivity, but is spread out over a large volume of material, such as contaminated soil. Diffuse NORM poses a different type of problem because of its high volume and low concentration of radioactive material. The following are six sources of diffuse NORM:
- Metal Mining & Processing Waste
- Coal Ash
- Phosphate Waste
- Uranium Mining Overburden
- Oil and Gas Production Wastes
- Water Treatment Residues
Diffuse NORM may pose a health hazard because of its many uses. For example, though most metal-mining waste is stored near where it is generated, small amounts have been used as construction backfill and road building materials. It is also used in concrete and wallboard.
Coal ash is primarily used as an additive in concrete and as backfill.
Phosphate waste (slag) from the processing of elemental phosphorous has been used in construction and in paving.
Uranium mining waste is the soil and rock that is removed during surface or underground uranium mining. This waste is sometimes used to backfill mined-out areas and to construct roads around the mining site.
Oil and gas production may produce radioactive pipe scale (a residue left in pipes from producing oil wells) and sludge that leave sites and equipment contaminated. In the past, some contaminated piping and other scrap metal have been used inadvertently by schools and other organizations for playground equipment, welding material, fencing, etc. because this contaminated metal was recycled before it was found to be contaminated.
Radiation-contaminated water treatment residue accumulates when radioactive material is filtered out of drinking water during the purifying process. This waste may be disposed of in landfills or lagoons. It may also be used in agriculture as a soil conditioner.
There is increasing
evidence that improper use or disposal of such
naturally-occurring radioactive materials can result in
significant contamination of the environment and elevated
radiation exposure. This can adversely affect the health of
those occupationally exposed, as well as the general public.
There are currently no federal regulations covering disposal of NORM. The State of North Dakota, as an Agreement State, does regulate all aspects of NORM (and other non-byproduct radioactive material). Currently there are no regulations specific to the control of NORM. NORM is covered by the same regulations that apply to other radioactive material in the state.
Material or equipment found to contain less than 5 picocuries of total radium per gram of material through accredited lab analysis is not considered NORM, by definition, and may be disposed of, or released for unrestricted use.
Material or equipment found to be
contaminated to levels above 5 picocuries per gram are
considered NORM and must be handled, stored, transported and
disposed of in accordance with the North Dakota
Radiological Health Rules.
For More Information
The safe handling, storage, transport and disposal of NORM is a very important issue. NORM or other radioactive waste disposal standards have changed substantially with improved technology and evolving environmental protection considerations. Regulatory programs and standards continue to change, so if you would like more information on the handling, storage, transport or disposal of NORM, contact:
DAVE STRADINGER, ENVIRONMENTAL SCIENTIST
Radiation Control Program
918 East Divide Avenue, 2nd Floor
Bismarck, ND 58501-1947
The Radiation Control Program pages are
maintained by James Lawson, RT