Section R. 299.4421 - Type II landfill design standards; liner systems for new units and lateral extensions of existing unitsRule 421.
(1) All new units and lateral extensions of existing units at a type II landfill shall be constructed with a composite liner and a leachate collection system that is designed and constructed to maintain less than a 1-foot depth of leachate over the liner, excluding the sump. To maintain less than a 1-foot depth of leachate over the liner, leachate collection systems for these units shall be designed and constructed in compliance with the provisions of R 299.4423.(2) All new units and lateral extensions of existing units that are unmonitorable units shall contain a leak detection system which is in compliance with the provisions of R 299.4424.(3) Type II landfill units that are either of the following shall be located or designed in accordance with the leakage control criteria of R 299.4422 so that the risks associated with any leakage through the composite liner required by subrule (1) of this rule are minimized: (a) New disposal areas. Owners and operators of new disposal areas shall demonstrate compliance as part of a construction permit application.(b) New units and lateral extensions at existing disposal areas that have not received waste before October 9, 1995. New units and lateral extensions of existing units shall not be subject to the standards of R 299.4422 if a complete operating license application is submitted 90 days before October 9, 1995.(4) The slope of a liner system shall not be more than 1 vertical to 3 horizontal or that necessary to ensure side slope stability. The director shall approve steeper side slopes than 1 to 3 if the owner or operator demonstrates that side slope stability will be maintained.(5) The upgrading of an existing disposal area in accordance with the provisions of subrules (1) and (2) of this rule does not require department approval. Construction of the landfill shall be certified in accordance with the provisions of R 299.4921 and the certification shall be submitted with as-built plans with the operating license application for the upgraded units.Mich. Admin. Code R. 299.4421