Each patent for a leased disposal site will provide that:

(a) The patentee shall comply with all Federal and State laws applicable to the disposal, placement, or release of hazardous substances;

(b) The patentee shall indemnify and hold harmless the United States against any legal liability or future costs that may arise out of any violation of such laws; and

(c) No portion of the land covered by such patent shall under any circumstance revert to the United States.