Determination of Texas Oil Fields Eligible for Variance from Area-of-Review Requirements in Underground Injection Control Regulations for Class II Injection Wells

Permitting of salt-water injection wells requires oil companies or operators to perform an Area of Review (AOR) study within a 0.25-mile radius of a proposed well. The purpose of an AOR study is to identify unplugged wells that may allow injected fluids to migrate upward from the production zone and endanger the overlying underground sources of drinking water (USDW).

The Bureau of Economic Geology (BEG) at the University of Texas at Austin, in conjunction with the Railroad Commission of Texas (RRC), evaluated oil fields in Texas for possible variance to the AOR permitting process based on the separation between production-zone fluid levels and the base of USDW. The purpose was for RRC and the industry to use these data and methodology in AOR variance applications and the review of Texas oil fields.