Section 211.1 - Purpose and scope(a) The regulations in this part govern leases and permits for the development of Indian tribal oil and gas, geothermal, and solid mineral resources except as provided under paragraph (e) of this section. These regulations are applicable to lands or interests in lands the title to which is held in trust by the United States or is subject to a restriction against alienation imposed by the United States. These regulations are intended to ensure that Indian mineral owners desiring to have their resources developed are assured that they will be developed in a manner that maximizes their best economic interests and minimizes any adverse environmental impacts or cultural impacts resulting from such development.(b) The regulations in this part shall be subject to amendment at any time by the Secretary of the Interior. No regulation that becomes effective after the date of approval of any lease or permit shall operate to affect the duration of the lease or permit, rate of royalty, rental, or acreage unless agreed to by all parties to the lease or permit.(c) The regulations of the Bureau of Land Management, the Office of Surface Mining Reclamation and Enforcement, and the Minerals Management Service that are referenced in §§ 211.4 , 211.5 , and 211.6 are supplemental to the regulations in this part, and apply to parties holding leases or permits for development of Indian mineral resources unless specifically stated otherwise in this part or in such other Federal regulations.(d) Nothing in the regulations in this part is intended to prevent Indian tribes from exercising their lawful governmental authority to regulate the conduct of persons, businesses, operations or mining within their territorial jurisdiction.(e) The regulations in this part do not apply to leasing and development governed by regulations in 25 CFR parts 213 (Members of the Five Civilized Tribes of Oklahoma), 226 (Osage), or 227 (Wind River Reservation).