Underground injection via Class II injection wells is a suitable technology for the continued safe and economically viable disposal of oil field brines in the United States. Currently, there is growing concern in industry regarding the regulatory fate of injection well technology. These concerns stem from the public's perception of risk due to use of this technology and from an increasingly restrictive regulatory environment. As environmental regulations become more comprehensive and restrictive, brine handling and disposal costs are becoming a more significant constraint for both new and existing production operations. The potential for increased operator liability, additional financial burdens, and new logistical challenges are related to current and projected increases in operating costs. These factors are now becoming contributing factors for production being prematurely abandoned or never developed.
In this paper, a number of technical arguments that support the continued use of underground injection are summarized along with historical information regarding injection practices. Class I and Class II wells are compared along with a brief update regarding new and developing Class II regulations.
The long-term fate of the oil and gas production base in the United States is dependent on continued access to the environmentally sound practice of underground injection at a reasonable cost. This fate is linked to the physical fate of injected waste, and even more importantly to the fate of regulatory affairs.