Amends the Mineral Lands Leasing Act of 1920 to provide that oil shale placer claims in existence on the date of enactment of such Act shall be deemed in compliance with such Act for purposes of perfection if: (1) annual assessment work on the claim has been completely performed; and (2) economically feasible oil shale extraction and production methods are in existence. Permits such claims to be converted to a lease under the Act if there has been substantial compliance with the requisite annual assessment work. Requires the Secretary of the Interior to cancel certain non-complying claims, and to provide compensation for such claims equal to the amount that can be demonstrated as expended for assessment and development work.