The proposed rules also address issues outside of the 2005 legislation. For example, the BLM rule would clarify distinctions between underground and surface coal leases for the purpose of levying royalties.

The proposal noted in recent years “much dialogue has taken place concerning whether various hybrid technologies for mining coal, specifically continuous high wall mining and auger mining, constitute underground mining or surface mining,” said the agency.

In the proposed rule, underground mine is defined as those in which “undisturbed earth is directly overhead” together with a roof control ventilation plan approved by the Mine Safety and Health Administration. Under the proposal, only mines meeting the definition will be eligible for the 8% underground royalty rate; the minimum 12.5% royalty rate will apply to coal recovered by any other extraction method.

In addition, the ONNR rule proposes extensive new information requirements not directly related to implementation of the 2005 legislation.

Comments on the proposed rules are due Oct. 11.