Well
Well means a hole drilled for the purpose of producing oil or natural gas, or a well into which fluids are injected.
Source
40 CFR § 60.5430a
Scoping language
As used in this subpart, all terms not defined herein shall have the meaning given them in the Act, in subpart A or subpart VVa of part 60; and the following terms shall have the specific meanings given them.