R 299.4307 Type III landfills; design standards; natural soil sites; lined sites.

Rule 307. (1) The design standards of this rule apply to both of the following: (a) New disposal areas for industrial waste. (b) New units and lateral extensions of existing units at a construction and demolition waste landfill. (2) Except as required by subrules (5) and (6) of this rule, a type III landfill shall be located and designed with either of the following: (a) A liner that is in compliance with subrule (4) of this rule. (b) A natural soil barrier that is in compliance with subrule (3)(a) of this rule. (c) For low-hazard industrial waste, a means of otherwise preventing groundwater contamination, as provided by subrule 3(b) of this rule. (3) The following provisions apply with respect to natural soil sites for type III landfills: (a) A natural soil barrier shall have a maximum demonstrated hydraulic conductivity of 1.0 x 10-7 cm/sec and shall meet the criteria specified in R 299.4912. The director may approve a combination of natural soils with a maximum demonstrated hydraulic conductivity of 1.0 x 10-6 cm/sec having a thickness that provides equivalent protection to 10 feet of 1.0 x 10-7 cm/sec soil. Type III natural clay sites where the clay does not extend to the surface shall include side cutoff walls or other barriers and controls to impede the lateral infiltration of water into the fill and to impede lateral flow of leachate out of the fill interior. (b) Applications for low-hazard industrial waste landfills at natural soil sites that do not meet the permeability or soil classifications of subdivision (a) of this subrule shall be considered based on the hydrogeologic characteristics of the site, including the permeability and thickness of the soils, the ability of the soils to attenuate leachate, groundwater level, and other factors particular to a specific site. In addition, all of the following requirements apply: (i) The applicant shall characterize the waste in accordance with R 299.4118a criteria established by the director and shall retest the waste annually, or on a more frequent schedule, as specified by the solid waste control agency if the character of the waste is variable. (ii) In the application, an applicant shall explain the rationale for the design using calculations, if applicable, and professional analyses to show how the proposed design is expected to be in compliance with the performance standards specified in R 299.4306. (iii) Two thousand feet of horizontal isolation shall exist in the direction of groundwater flow measured from the solid waste boundary to public water supply wells and domestic wells in existence at the time of an advisory analysis. (iv) One thousand feet of horizontal isolation shall exist in directions lateral to or upgradient of the direction of groundwater flow measured from the solid waste boundary to public water supply wells and off-site domestic wells in existence at the time of advisory analysis. (v) Based on the hydrogeological evaluation, the director may approve a decrease in the isolation distances specified in paragraphs (ii) to (iv) of this subdivision. (vi) An applicant shall demonstrate, by technical calculations, considering the design details and operational procedures specific to the site, how run-off from those portions of the landfill that contain solid waste will be managed to comply with R 299.4306. (4) All of the following may be used as a liner system for type III landfills: (a) A compacted soil liner which has a minimum thickness of 3 feet and which is in compliance with the specifications of R 299.4913. (b) A composite liner. (c) A flexible membrane liner which is in compliance with the specifications of R 299.4915 and which is not less than 30 mils thick, if the liner is installed on stable soil not less than 4 feet thick and which has a hydraulic conductivity that is less than 1.0 x 10- 5 cm/sec. (d) Other liner materials, modified soils, or technologically advanced liner systems, based on data supplied by the applicant regarding the system's durability, permeability, resistance to sunlight and chemicals, and performance in similar applications. The director shall determine the acceptability of the data and proposed design. (5) New disposal areas for industrial solid waste that do not meet the criteria for low- hazard industrial solid waste contained in section 11504(7) shall, at a minimum, contain a composite liner. (6) A new unit or a lateral extension of an existing unit at a type III landfill that is an unmonitorable unit shall not be licensed unless the unit contains a leak detection system that is monitored in accordance with the approved hydrogeological monitoring plan. The owner or operator of an unmonitorable unit who installs a leak detection system to monitor the unit shall include in the hydrogeological monitoring plan provisions for monitoring the leak detection system in accordance with R 299.4437.