Operational
Operational means that a uranium mill tailings pile or impoundment is being used for the continued placement of uranium byproduct material or is in standby status for such placement. A tailings pile or impoundment is operational from the day that uranium byproduct material is first placed in the pile or impoundment until the day final closure begins.
Source
40 CFR § 192.31
Scoping language
References in this subpart to other parts of the Code of Federal Regulations are to those parts as codified on January 1, 1983.