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Background The U.S. Environmental Protection Agency (EPA), Underground Injection Control Program (UIC) has recognized that conditions can exist that make it necessary to perform well-by-well Area of Review (AOR)s and that wells in a basin, producing trend, region, field, or portion of such areas could be exempt from an AOR through a variance program. The variance could be granted for the following conditions: Underground Source of Drinking Water (USDW) is absent; reservoir is underpressured relative to the USDW; local geologic conditions preclude upward movement that could endanger USDW; and other compelling evidence exists. A scientific methodology to identity areas for AOR variance was developed at the University Missouri-Rolla. This methodology has been applied in several states and to date, has been effective in all applications. In order to apply that methodology, it is necessary to have reliable subsurface information, (i.e. depth to groundwater, reservoir and aquifer pressures, well construction data. well abandonment information, etc.) To effectively perform a variance over large areas, subsurface and well information in electronic format is essential. Through a contract with the U.S. Department of Energy (DOE), Office of Fossil Energy, Bartlesville Project office, BDM Petroleum Technologies has been assisting several states in AOR variance projects and electronic well information data.
Approach The AOR variance program was established by DOE to provide assistance to the state regulatory agencies and the affected oil and gas industry in developing AOR variance programs over large areas of the states. The first step in developing an individual state plan has been to form a statewide steering committee. The committee is chaired by the state UIC Director with members from, at least, three large and three small oil and gas companies that operate in the particular state. The committee then develops a recommended plan that BDM will prepare and submit to DOE for approval. The state-wide plan should consider several different factors: Is the state a UIC Class II Primacy State; Will industry support the plan and obtain a cost savings; Are appropriate Rules and Regulations in place to allow for AOR variance; How quickly will results be noticed in the state; and Are the costs for the state plan competitive and reasonable. As of this writing, BDM has been working with Oklahoma, California and Texas on implementation of their state-wide AOR variance plans.
Oklahoma plan The State of Oklahoma had rules in place to allow for AOR variance. To obtain the largest area(s) of variance for the state, basic well construction information and some hydrogeologic information was needed in electronic format. BDM is currently converting the State's Hydrogeologic Maps from hard copy to electronic form and working with the University of Oklahoma GEO Data group to obtain well construction information for the state data base system. We have also been assisting the state in design, architecture and development of a complete integrated system. When completed, the state system for Oklahoma will be fully interactive, integrate all state agencies with oil and gas responsibilities and provide real time access to public information.
California Plan The State of California had a unique set of concerns about allowing for AOR variance. The State Oil and Gas Agency has the authority to allow for AOR variance and given the scientific methodology could easily permit a variance. However, most of the production and injection in California occurs in populated urban areas and any AOR variance allowed would need very current and accurate information. Again, the need for reliable electronic well construction data was realized in California. P. 271^
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