(1) The purpose of this subchapter is to provide uniform standards governing the storage, treatment, recycling, recovery, and disposal of solid waste.

(2) The rules in this subchapter are adopted to discharge the department's responsibilities under Title 75, chapter 10, part 2, MCA, "The Montana Solid Waste Management Act", by adopting rules governing solid waste management systems.

(3) These rules apply to owners and operators of solid waste management systems, except as otherwise specifically provided in this subchapter.

(4) The effective dates of ARM 17.50.506 and 17.50.511(1) (e) and (g) are extended until April 9, 1994, as they apply to existing landfill units and lateral expansions to existing units that meet the following requirements:

(a) the unit disposed of less than 100 tons per day of solid waste between October 9, 1991, and October 9, 1992;

(b) the unit does not dispose of more than an average per month of 100 tons per day of solid waste between October 9, 1993 and April 9, 1994; and

(c) the unit is not on the national priorities list (NPL) as found in 40 CFR, part 300, appendix B.

(5) Existing MSWLF units that meet the requirements for the small community exemption found in ARM 17.50.506(16) or the requirements of (4) of this rule that receive waste after October 9, 1993, and stop receiving waste prior to April 9, 1994, are only subject to the final cover requirements found in ARM 17.50.530.   Final cover must be installed by October 9, 1994.   Owners or operators that fail to complete cover installation by October 9, 1994, are subject to all of the requirements of this subchapter unless otherwise specified.