Conclusions and Recommendations
In December 2010, the US Environmental Protection Agency (EPA) promulgated a new rule for CO
under the existing Underground Injection Control (UIC) regulatory program. This new class applies only to wells that inject CO
Wells injecting CO 2 for enhanced oil recovery (EOR) will continue to be treated
as Class II wells. Compared to past UIC regulations, the new Class VI rules have more adaptive elements and incorporate some of the advances in modeling and monitoring that have emerged in the thirty years since the fi rst UIC rules were promulgated. However, because none of the regulatory requirements imposed on other well classes have been similarly updated, the Class VI rules can be read as disproportionately stringent.