Section R. 299.4440 - Type II landfill groundwater monitoring; detection monitoring programRule 440.
(1) Detection monitoring is required at type II landfill units at all groundwater monitoring wells defined in R 299.4906. At a minimum, a detection-monitoring program for a type II landfill shall include monitoring for all of the following constituents:(a) The primary indicators listed in R 299.4450, conductivity and pH, at least quarterly during the active life and semiannually during the postclosure period, except as provided for in subrules (5) and (6) of this rule.(b) The following constituents listed at least semiannually during the active life of the facility and the postclosure period, except as provided in subrules (2) to (6) of this rule: (i) Heavy metals that are listed in R 299.4452.(ii) Primary volatile organic constituents listed in R 299.4453.(iii) Secondary organic constituents listed in R 299.4454.(2) The director shall waive the sampling and analysis of some or all of the heavy metals specified in R 299.4452 if other inorganic indicator parameters listed in R 299.4450 or R 299.4451 provide a reliable indication of inorganic releases from the unit to groundwater. In determining whether to approve a waiver, the director shall consider all of the following factors:(a) The types, quantities, and concentrations of constituents in the wastes that are managed at the type II landfill unit.(b) The mobility, stability, and persistence of waste constituents or their reaction products in the unsaturated zone beneath the type II landfill unit.(c) The detectability of indicator parameters, waste constituents, and reaction products in the groundwater.(d) The concentration and variance of monitoring parameters in the groundwater background.(3) The owner and operator of a type II landfill unit that contains a secondary collection system shall be deemed to have met the criteria of subrule (2) of this rule and may conduct sampling and analysis for primary indicators listed in R 299.4450 in place of the heavy metals listed in R 299.4452 if all of the following conditions are met:(a) Leachate monitoring shows that the concentration of all of the indicators in leachate is not less than 10 times the concentration in groundwater.(b) Secondary collection system monitoring shows all of the following: (i) That the allowable flow rate has not been exceeded.(ii) That the concentration of 2 or more indicators in the system is not more than the following threshold values for 2 consecutive sampling events:(A) For chlorides, 250 mg/l.(C) For sulfates, 250 mg/l.(D) For total inorganic nitrogen, 10 mg/l.(E) For total dissolved solids, 500 mg/l.(F) For other constituents, a value approved by the director.(iii) That volatile organics listed in R 299.4453 have not been detected in the secondary collection system.(iv) That the concentration of metals listed in R 299.4452 has not exceeded the part 201 generic residential cleanup criteria contained in R 299.44 and R 299.46.(c) The unit is a monitorable unit.(d) The concentration of the indicators in groundwater is normally distributed.(4) The director shall delete any of the monitoring parameters listed in R 299.4452 to R 299.4454 for a type II 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. An owner or operator may demonstrate that a constituent is not expected to be in or derived from the waste if the constituent and any breakdown products are not detectable in leachate at practical quantitation limits approved by the director based on historic analysis of leachate from not less than 2 sampling events.(5) The owner and operator of a type II landfill may apply to the director for an appropriate alternative frequency for repeated sampling and analysis for pH, conductivity, and the constituents specified in R 299.4450 to R 299.4454, during the active life, including closure, and the postclosure care period. The alternative frequency during the active life, including closure, shall be at least semiannually for pH, conductivity, and the constituents specified in R 299.4450 and R 299.4451, and at least annually for the constituents specified in R 299.4452 to R 299.4454. The alternative frequency shall be based on consideration of all of the following factors: (a) The lithology of the aquifer and unsaturated zone.(b) The hydraulic conductivity of the aquifer and unsaturated zone.(c) The groundwater flow rates.(d) The minimum distance of travel between waste and the closest downgradient monitoring well screen.(e) The presence of an alternative monitoring system, such as a secondary collection system.(f) The resource value of the aquifer.(6) The owner or operator of a type II landfill unit shall be deemed to meet the criteria of subrule (5) of this rule and may reduce sampling of the following constituents to the following frequency during the active life and 30-year postclosure period if the following conditions are met as applicable: (a) The heavy metals listed in R 299.4452 and secondary organic constituents listed in R 299.4454 to annually if the active portions of the unit contain a composite liner underlain by a natural soil barrier in compliance with the leakage control criteria of R 299.4422(2).(b) For monitorable units which contain a secondary collection system in the active portion, but which are not underlain by a natural soil barrier meeting the criteria of R 299.4422(2), all constituents listed in R 299.4450 to R 299.4454 to the following frequency:(i) To annually, if the average daily flow rate in the secondary collection system of all landfill cells in the active portion does not exceed the following flow rates during the previous 6 months: (A) A value of 5 gallons per acre per day for landfill cells that have less than 2 feet of compacted clay in the primary liner.(B) A value of 50 gallons per acre per day for landfill cells that have not less than 2 feet of compacted clay in the primary liner.(ii) To semiannually, if the average daily flow rate in the secondary collection system of any landfill cell in the active portion has exceeded the flow rates specified in paragraph (i) of this subdivision in the previous 6 months, but has not exceeded the following action flow rates for the cell during the previous 6 months: (A) A value of 25 gallons per acre per day for landfill cells that have less than 2 feet of compacted clay in the primary liner.(B) A value of 200 gallons per acre per day for landfill cells that have not less than at least 2 feet of compacted clay in the primary liner.(c) For monitorable units that contain a secondary collection system in the active portion underlain by a natural soil barrier meeting the criteria of R 299.4422(2), to annually if the average daily flow rate in the secondary collection system of any landfill cell in the active portion has not exceeded the following flow rates during the previous 6 months: (i) A value of 25 gallons per acre per day for landfill cells that have less than 2 feet of compacted clay in the primary liner.(ii) A value of 200 gallons per acre per day for landfill cells that have not less than 2 feet of compacted clay in the primary liner.(7) If insufficient background data exists to perform statistical analysis, a minimum of 4 independent samples shall be collected and analyzed during the first sampling event. At least 1 sample from each detection monitoring well shall be collected and analyzed during subsequent sampling events. An alternate background collection schedule may be approved by the director. An interim statistical method may be utilized during the period in which background data is collected.(8) If the owner and 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 at any monitoring well at the solid waste boundary or at other monitoring locations required by the director, then the owner and operator shall do both of the following:(a) Within 14 days of the determination, place a notice in the operating record that indicates which constituents have shown statistically significant increases from background levels and notify the director that the notice is placed in the operating record.(b) Prepare and submit to the director an assessment monitoring plan that is in compliance with R 299.4441 and a response action plan that is in compliance with R 299.4442 within 45 days of the determination, or pursuant to an alternate schedule approved by the director, except as provided in subrule (9) of this rule.(9) The owner and operator may demonstrate to the director that a source other than a landfill unit caused the contamination or that the statistically significant increase resulted from error in sampling, analysis, statistical evaluation or from natural variation in groundwater quality. A report that documents the demonstration shall be certified by a qualified groundwater scientist, be submitted to the director within 30 days of the determination specified in subrule (8) of this rule, and be placed in the operating record. If the director determines that the alternate source demonstration prepared pursuant to this subrule has not been successfully provided, the deficiencies shall be specified to the petitioner in writing and the petitioner granted 15 days to address those deficiencies identified by the director. If a successful demonstration is made and documented, then the owner or operator shall do the following:(a) Continue detection monitoring as specified in this rule.(b) 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.(10) If the director notifies the owner and operator that a successful demonstration has not been made, then, within 15 days of notification by the director, the owner and operator shall prepare an assessment monitoring program as required in R 299.4441 and submit a response action plan to the director as required in R 299.4442.Mich. Admin. Code R. 299.4440
1993 AACS; 1999 AACS; 2005 AACS; 2015 MR 5, Eff. March 11, 2015