The 1980 amendments to the Safe Drinking Water Act (SDWA) added a new Section 1425 which provides an alternative means for States to acquire primary enforcement responsibility for the control of underground injection related to the recovery and production of oil and natural gas. This document contains guidance on: (1) how States may apply for approval under Section 1425; and (2) the criteria EPA will use in approving or disapproving applications under Section 1425. EPA is mindful of the fact that, in enacting Section 1425, Congress intended that States be offered an alternative to the detailed requirements of the regulations promulgated at 40 CFR 122 (144), 123 (145), 124 and 146, and that State programs to control injections related to oil and gas production be considered on their merits. Nevertheless, Section 1425 does require a State to demonstrate that such portion of its Underground Injection Control (UIC) program: (1) meets the requirements of Section 1421(b)(1)(A) through (D); and (2) represents an effective program to prevent injection which endangers drinking water sources.