(1) "Facility" means any site, location, structure, or property used or to be used for the storage, disposal, or burial of radioactive materials or waste, which lies within the one hundred acre tract described in the perpetual care agreement between the state of Washington and the United States government executed July 29, 1965.

(2) "Department" means the Washington state department of ecology.

(3) "Perpetual care and maintenance" means the activities necessary to stabilize and secure a closed facility during the perpetual care period, including but not limited to: Trench stabilization; upkeep of erosion control measures, fences, and warning signs; and sampling of monitor wells.

(4) "Sublessee" means a party to a sublease with the state of Washington for a portion of the one thousand acres of land, as described in the state's lease with the United States government executed September 10, 1964, lying within the Hanford Reservation.