Course Duration: Approxamaty 50 minutes

Burnt Mountain LLC. Learning Management System (BMLMS)

Technologically Enhanced Naturally Occurring Radioactive Material (TENORM) is defined as, "Naturally occurring radioactive materials that have been concentrated or exposed to the accessible environment as a result of human activities such as manufacturing, mineral extraction, or water processing.” 

"Technologically enhanced" means that the radiological, physical, and chemical properties of the radioactive material have been concentrated or further altered by having been processed, or beneficiated, or disturbed in a way that increases the potential for human and/or environmental exposures. 

Naturally Occurring Radioactive Material (NORM) is defined as, “Materials which may contain any of the primordial radionuclides or radioactive elements as they occur in nature, such as radium, uranium, thorium, potassium, and their radioactive decay products, such as radium and radon, that are undisturbed as a result of human activities." 

Background radiation, which is present in terrestrial, cosmic, and cosmogenic sources, is always around us. Some man-made radioactivity is considered part of background for regulatory purposes (e.g., fallout from weapons testing).

Sources of TENORM

Radionuclides are found naturally in almost all soils, rocks, surface water and groundwater. Bringing natural resources from below the surface to above the ground also brings up materials that naturally contain radionuclides. These naturally radioactive materials are called TENORM. Radionuclides commonly found in TENORM are radium, radon, uranium, potassium and thorium. The level of radioactivity in TENORM can vary widely.

TENORM can be found in solids, liquids, sludges and/or gases. It’s possible for TENORM to come from different parts of the oil and gas extraction processes. Here are a few examples:

• Drill cuttings: When drilling for oil and gas, rock is ground into small pieces using a sharp bit. These pieces of rock, called drill cuttings, can contain radioactive elements that are found inside the rock.
• Flowback and produced water: These terms describe the water that comes back to the surface during and after drilling. Flowback water is the solution that returns to the surface after injecting materials into the well for fracking. Industrial water, sand and chemicals mix with water in the formation to create flowback water. Produced water is the salty liquid that is brought to the surface with oil and gas after the well is developed and put into production.
• Pipe scale: When water is pumped in and out of well and storage tanks, a coating called pipe scale builds up around the inside of the pipe. Pipe scale is made up of the natural minerals found in water, which sometimes include radionuclides. Radioactivity in pipe scale can be quite high.
• Sludges, sediments, and filters: Sludge is an oily, loose material from produced water that often ends up in water storage tanks. Sediments are the more solid material, often present in water storage tanks. Filters can contain TENORM that is captured as liquid and gas passes through.

Wastes generated from oil and gas drilling must be properly managed to keep the radionuclides in these wastes from spreading to surrounding areas. One factor that affects the movement of radionuclides in the environment is how well they dissolve in water (solubility). For example, radium is more soluble than thorium. Therefore, under certain conditions, radium can spread more easily through the groundwater.

Employees who work at drilling sites are the most likely group to be exposed to TENORM from oil and gas drilling and production. Some states have worker safety programs in place to ensure workplace safety. To learn more about oil and gas drilling sites in your area, contact your state geological survey or health department.

Risks and Health Effects

The uncontrolled release of radioactivity related to TENORM levels may pollute the environment and endanger human health. Hazardous radiation may enter the human body through various ways, of exposure that are classified either internal or external, such as absorption, wounds, inhalation and ingestion

Controls have been adopted for TENORMs to avoid the risk of these wastes, efforts to shield radiation should be made to protect workers and the public, and any regulations set in place for radiological protection must consider the additional risks that exceed the exposure to native natural radioactivity

Detection and Measurement of TENORM

Crude oil and its products and wastes are among the significant sources of naturally occurring radioactive materials (NORMs). These materials may be enhanced to high levels due to technological and human activities, which are called technologically enhanced naturally occurring radioactive materials (TENORMs). Thus, the average radioactivity of these radionuclides sometimes exceeds the exemption level of 10 000 Bq kg−1, which is recommended by the IAEA's safety standards. TENORMs in the oil and gas industry may generate greater radioactivity levels, which eventually represents potential environmental and health risks. This will require continuous attention by monitoring and surveillance during routine processes in the petroleum industry.

The results of a study in the United States shows low concentrations of uranium in crude oils in the range of 0.0015. 0.015 ppm for uranium in crude oil is typical in the U.S. In the study, the concentration of uranium in petroleum products in other places of the world are much higher than in the U.S.

Safety Measures and Protective Actions

States typically regulate TENORM under their general radiation safety regulations. Several states, however have specific NORM (naturally occurring radioactive materials) or TENORM regulations of which employers should be aware. These regulations appear to focus primarily on proper disposal of TENORM-contaminated materials.

Worker Protection
As noted above, radioactive decay of radium and radon may potentially expose oilfield workers to ionizing radiation. The following precautions should be taken to assist in minimizing exposure to TENORM-contaminated materials.

1. Employees and contractors should be advised of the presence of this contamination and of procedures to minimize exposure.

2. Areas with detectible levels of NORM should be subject to radiological controls.

3. Direct skin contact with radioactive scale and solids should be avoided to the extent reasonably possible. Neoprene, PVC gloves should be worn to minimize skin contact.

4. Eating, drinking, smoking, and chewing should not be allowed in the work area where work is being performed on contaminated equipment or where contaminated soil is being handled.

5. Personnel should thoroughly wash their hands and faces after working with contaminated equipment, and before eating, drinking, or smoking and at the end of the day.

6. Only essential personnel should be allowed in NORM-contaminated areas.

7. If possible, openings on contaminated equipment should be sealed or wrapped in plastic. Work on contaminated equipment, such as cutting, grinding, sand-blasting, welding, drilling, or polishing, should be kept to a minimum.

8. Change out of potentially contaminated clothes and shoes before leaving the work site (i.e., before returning to the car, home, or office).

9. Do not re-use or bring home discarded equipment or material such as pipes, devices, bricks, rocks, or water.

10. If work requires any action that might produce dust or if loose contamination is suspected, the following additional precautions should be taken:

• A respirator appropriate for radioactive particulates should be worn and activities should be conducted in well-ventilated areas to which access has been restricted.
• Suitable coveralls and gloves should be worn.
• Plastic ground covers should be utilized to the extent possible to contain contaminants and facilitate cleanup.
• Gloves, respirators, coveralls, and rags should be decontaminated or placed in double bags, sealed, and held for proper disposal.

Because radon is a gas, it will disperse into the atmosphere upon release. Exposure may be reduced by avoiding:

• Enclosed or confined spaces where the gas may accumulate
• Areas where produced water or other waste materials are being agitated or aerosolized

As noted above, radon decay progeny are solids and usually attached to airborne dust particles. NIOSH-certified respirators with N95 filters or better when used with a respirator program complying with 29 CFR 1910.134 or similar regulations may help reduce the potential inhalation exposure to these particles.

Transportation

See the above regulations for the State of Colorado for specific guidance on the transport of TENOM.