Naturally Occurring Radioactive Materials (NORM) are found naturally in the Earth’s crust as a result of radioactive elements created through cosmic processes, reservoir rock formations, formation water, natural gas, sea water and radionuclides created through radioactive decay of these elements.
There are two primary types of NORM in which the oil and gas industry is concerned: Radium-226 and Radium-228 and their radioactive decay products (“daughters”), in particular Radon-222, Lead-210, and Polonium-210. The production of oil and gas generates waste and materials that may contain NORM. NORM emits alpha and beta particles along with small amounts of gamma radiation.
Workers employed in the areas of cutting and reaming oilfield pipe, removing solids from tanks and pits, and refurbishing gas-processing equipment may be exposed to particles containing levels of alpha-emitting radionuclides that could pose health risks if inhaled or ingested. NORM waste arises when these materials are concentrated through industrial activities, and can develop significant chemotoxic hazards comparable in level to the radiotoxic hazard.
The waste management hierarchy concept is central to the development of plans, starting with waste prevention, minimization and safe final disposal (i.e. to landfill) as the option of last resort.