R 299.4318 Type III landfill operating requirements; groundwater monitoring.

Rule 318. (1) The requirements of this rule apply to all type III landfill units, except as provided in subrule (2) of this rule. (2) The director shall reduce or waive certain groundwater monitoring requirements of this rule if the owner or operator can demonstrate compliance with either of the following provisions: (a) That there is no potential for migration of hazardous constituents from that type III unit to the uppermost aquifer during the active life of the unit and the 30-year post-closure care period. The demonstration shall be certified by a qualified groundwater scientist and approved by the director and shall be based upon both of the following: (i) Site-specific field collected measurements, sampling, and analysis of physical, chemical, and biological processes that affect contaminant fate and transport. (ii) Contaminant fate and transport predictions that maximize contaminant migration and consider impacts on human health and the environment. (b) That a discharge to the uppermost aquifer will occur, but that such discharge is authorized and monitored under a permit issued pursuant to the provisions of part 31 of the act. (3) Owners and operators of type III landfill units shall comply with the groundwater monitoring requirements of this rule before waste can be placed in the unit. (4) Once established at a type III landfill unit, groundwater monitoring shall be conducted throughout the active life and 30-year post-closure care period of that unit. (5) Groundwater monitoring is required at type III landfill units at all groundwater monitoring wells defined pursuant to the provisions of R 299.4906. At a minimum, a groundwater monitoring program for a type III landfill shall include monitoring for the following constituents: (a) The primary inorganic indicators that are listed in the provisions of R 299.4450 or alternate indicators listed in the provisions of R 299.4451 quarterly during the active life of the facility and semiannually during the 30-year post-closure period, except as provided for in subrule (7) of this rule. (b) The constituents that are listed in the provisions of R 299.4452, R 299.4453, and R 299.4454, annually during the active life of the facility and the 30-year post-closure period, except as provided in subrule (6) of this rule. (c) Other constituents required by a construction permit or approved hydrogeologic monitoring plan. (6) The director shall delete any of the monitoring parameters specified in subrule (5) of this rule for a type III landfill unit if it can be shown that the removed constituents are not reasonably expected to be in or derived from the waste that is contained in the unit in significant concentrations. An owner or operator may demonstrate that a constituent is not expected to be in or derived from the waste in significant concentrations if 1 of the following conditions exists based on all available historical waste characterizations pursuant to the provisions of R 299.4118a or the historical analysis of leachate from not less than 2 samplings: (a) The constituent and any breakdown products are not and have not been detected at practical quantitation limits approved by the director. (b) The concentration of the constituent is below the background concentration of the constituent in groundwater. (c) The concentration of the constituent is below the part 201 generic residential criteria contained in R 299.44 and R 299.46, and other constituents will serve as better indicators of leakage from the landfill unit. (7) The owner and operator of a type III landfill may apply to the director for an appropriate alternative frequency for repeated sampling and analysis for constituents that are specified in subrule (5) of this rule during the active life, including closure, and the 30 year post-closure care period. The alternative frequency during the active life, including closure, shall be not less than semiannually. The alternative frequency shall be based on consideration of all of the following factors: (a) Lithology of the aquifer and unsaturated zone. (b) Hydraulic conductivity of the aquifer and unsaturated zone. (c) Groundwater flow rates. (d) Minimum distance of travel between waste and the closest downgradient monitoring well screen. (e) The presence of an alternate monitoring system, such as a secondary collection system. (8) A minimum of 4 independent samples from each background and downgradient well shall be collected and analyzed during the first sampling event. An alternate background collection schedule may be approved by the department. At least 1 sample from each background and downgradient well shall be collected and analyzed during subsequent sampling events. (9) If the owner or operator determine, pursuant to a statistical test specified in R 299.4908, that there is a statistically significant increase over background for 1 or more of the constituents or indicators listed in subrule (5) of this rule at any monitoring well at or within the solid waste boundary, or at other monitoring locations required by the director, then the owner and operator shall do all of the following: (a) Within 14 days of the determination, place a notice in the facility’s files that indicates which constituents have shown statistically significant increases from background levels and notify the director. (b) Within 30 days of the determination, the owner and operator may demonstrate to the director that a source other than a landfill unit or other source at the facility caused the contamination, that the statistically significant increase resulted from error in sampling, analysis, statistical evaluation, or natural variation in groundwater quality, or that the increase is authorized by a permit that is issued pursuant to the provisions of part 31 of the act. A report that documents this demonstration shall be certified by a qualified groundwater scientist, be submitted to the director within 30 days of the determination and be placed in the facility’s files. If the director notifies the owner or operator that a successful demonstration has not been made, then within 15 days of the notification by the director the owner and operator shall submit a response action plan to the director as required in R 299.4319. If a successful demonstration is made and documented, the owner or operator shall do the following: (i) Continue detection monitoring as specified in this rule. (ii) Determine whether the presence of hazardous constituents in groundwater renders any new units or lateral extensions within the solid waste boundary unmonitorable. If so, the owner and operator shall develop a schedule for submitting revised engineering plans for such lateral extensions or new units that include a leak detection system. 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.