16 U.S.C. § 8542: Permit flexibility

The Secretary concerned shall establish guidelines to allow a holder of a special recreation permit under subsection (h) of section 6802 of this title (as amended by this title), to engage in another recreational activity under the special recreation permit that is substantially similar to the specific activity authorized under the special recreation permit. is comparable in type, nature, scope, and ecological setting to the specific activity authorized under the special recreation permit; does not result in a greater impact on natural and cultural resources than the impact of the authorized activity; any other holder of a special recreation permit or other permit; or any other authorized use of the Federal recreational lands and waters; and any applicable laws (including regulations); and the land management plan, resource management plan, or equivalent plan applicable to the Federal recreational lands and waters. notify the Secretary concerned of an inability to use visitor-use days annually allocated to the recreation service provider under the special recreation permit; and surrender to the Secretary concerned the unused visitor-use days for the applicable year for temporary reassignment under section 8547(b) of this title . To ensure a recreation service provider described in paragraph (1) is able to make an informed decision before surrendering any unused visitor-use day under paragraph (1)(B), the Secretary concerned shall, on the request of the applicable recreation service provider, determine and notify the recreation service provider whether the unused visitor-use day meets the requirement described in section 8546(b)(3)(B) of this title before the recreation service provider surrenders the unused visitor-use day. Nothing in this section affects any authority of, regulation issued by, or decision of the Secretary concerned relating to the use of electric bicycles on Federal recreational lands and waters under any other Federal law.