R 299.4309 Industrial waste surface impoundments closed as landfills; design standards; testing of wastes.

_{(Effective January 6, 1982; revised October 7, 1993; revised April 12, 1999)}

Rule309.

            (1)  The requirements of this rule apply to a surface impoundment which receives low-hazard industrial waste sludges or slurries that contain free liquids and which is an impoundment where solid waste will remain after closure.  This rule does not apply to landfills that are in compliance with the leachate management requirements of R 299.4308, except as provided in this rule.  An industrial waste surface impoundment that is closed as a landfill shall be in compliance with all parts of these rules designated as applying to type III  landfills.

            (2)  In the construction permit application for an industrial waste surface impoundment that is closed as a landfill, the engineer shall explain the rationale for the design, using calculations, if applicable, and professional analyses to show how the proposed design is expected to comply with the groundwater quality performance standards of R 299.4306.

            (3)  All wastes to be disposed of in an industrial waste surface impoundment that is closed as a landfill, shall have been subjected to the leaching test protocol specified in R 299.4311 and shall be classed as a low-hazard industrial waste.

            (4)  Free liquids in an industrial waste surface impoundment shall be discharged in accordance with a permit which is issued under part 31 of the act and which considers the effect of the discharge on surface and groundwater.

            (5)  A surface impoundment shall maintain enough freeboard to prevent any overtopping of the dike by overfilling, wave action, or a storm, but not less than 2 feet at any time.  The owner or operator shall inspect the freeboard level at least once each week to ensure compliance with this subrule.

            (6)  An earthen dike at a surface impoundment shall have a protective cover, such as grass or rock, to minimize wind and water erosion and to preserve its structural integrity.  The owner or operator shall inspect an earthen dike at least once per week to detect any deterioration or failure in the impoundment.

            (7)  At closure, the owner or operator of a surface impoundment that is closed as a landfill shall do all of the following unless the director determines that such actions are not necessary:

                        (a)  Eliminate free liquids by removing liquid wastes or solidifying the remaining wastes and waste residues.

                        (b)  Stabilize remaining wastes to a bearing capacity that is sufficient to support final cover.

                        (c)  Cover the surface impoundment with a final cover that is in compliance with the requirements of R 299.4304.

                        (d)  Conduct groundwater monitoring and postclosure maintenance in accordance with rules applicable to type III landfills.