CRAWFORD, Neb. (AP) — Federal regulators will hold a hearing on a proposed expansion at a uranium mine in the Nebraska Panhandle.

The Nuclear Regulatory Commission says it will hold a hearing on Oct. 30 in Crawford, Nebraska, about the Crow Butte Resources mine.

Regulators say the Oglala Sioux Tribe is challenging the proposed expansion at the mine.

Previously, environmental groups have raised concerns about whether water from mine could contaminate the underground aquifer.

Regulators granted a license extension through 2024 in 2014.