40 CFR § 61.20
Designation of facilities
June 9, 2020
The provisions of this subpart are applicable to the owner or operator of an active underground uranium mine which:
(a) Has mined, will mine or is designed to mine over 90,720 megagrams (Mg) (100,000 tons) of ore during the life of the mine; or
(b) Has had or will have an annual ore production rate greater than 9,072 Mg (10,000 tons), unless it can be demonstrated to EPA that the mine will not exceed total ore production of 90,720 Mg (100,000 tons) during the life of the mine.
[54 FR 51694, Dec. 15, 1989, as amended at 65 FR 62151, Oct. 17, 2000]