Update on cavern disposal of NORM-contaminated oil field wastes.

Some types of oil and gas production and processing wastes contain naturally occurring radioactive material (NORM). If NORM is present at concentrations above regulatory levels in oil field waste, the waste requires special disposal practices. The existing disposal options for wastes containing NORM are limited and costly. Argonne National Laboratory has previously evaluated the feasibility, legality, risk and economics of disposing of nonhazardous oil field wastes, other than NORM waste, in salt caverns. Cavern disposal of nonhazardous oil field waste, other than NORM waste, is occurring at four Texas facilities, in several Canadian facilities, and reportedly in Europe. This paper evaluates the legality, technical feasibility, economics, and human health risk of disposing of NORM-contaminated oil field wastes in salt caverns as well. Cavern disposal of NORM waste is technically feasible and poses a very low human health risk. From a legal perspective, a review of federal regulations and regulations from several states indicated that there are no outright prohibitions against NORM disposal in salt caverns or other Class II wells, except for Louisiana which prohibits disposal of radioactive wastes or other radioactive materials in salt domes. Currently, however, only Texas and New Mexico are working on disposal cavern regulations, and no states have issued permits to allow cavern disposal of NORM waste. On the basis of the costs currently charged for cavern disposal of nonhazardous oil field waste (NOW), NORM waste disposal in caverns is likely to be cost competitive with existing NORM waste disposal methods when regulatory agencies approve the practice.