Mich. Admin. Code R. 299.4907

Current through Vol. 24-10, June 15, 2024

Section R. 299.4907 - Landfill groundwater monitoring; sampling and analysis requirements

Rule 907.

(1) The groundwater-monitoring program for a landfill shall include consistent sampling and analysis procedures that are designed to ensure monitoring results that provide an accurate representation of groundwater quality at the background and downgradient wells that are installed in compliance with R 299.4906. The owner or operator shall notify the director that the sampling and analysis program documentation has been placed in the operating record and that the program shall include procedures and techniques for all of the following:

(a) Sample collection.

(b) Sample preservation and shipment.

(c) Analytical procedures.

(d) Chain of custody control.

(e) Quality assurance and quality control.

(2) The groundwater-monitoring program shall include sampling and analytical methods that are appropriate for groundwater sampling and that accurately measure hazardous constituents and other monitoring parameters in groundwater samples. Groundwater samples for metals shall be field-filtered before laboratory analysis, unless filtered samples alone will not accurately measure the concentration of metals in the given geologic setting, such as in permeable soils and karst terrains.

(3) The sampling procedures and frequency shall be protective of human health and the environment.

(4) Analytical methods that are used for groundwater monitoring samples shall be those specified in R 299.4450 to R 299.4454 and shall achieve practical quantitation limits approved by the director.

(5) Groundwater elevations shall be measured in each well immediately before purging each time groundwater is sampled. The owner or operator shall determine the rate and direction of groundwater flow each time groundwater is sampled. Groundwater elevations in wells that monitor the same disposal area shall be measured within a period of time that is short enough to avoid temporal variations in groundwater flow which could preclude an accurate determination of groundwater flow rate and direction.

(6) Groundwater elevations shall be determined by methods that are precise to 1/8 of an inch or 0.01 feet, as measured from the top of the well casing.The top of the well casing shall be related to a permanent reference point using United States geological survey datum.

(7) The owner and operator shall establish background groundwater quality in a hydraulically upgradient or background well or wells for each of the monitoring parameters or constituents that are required in the particular groundwater-monitoring program which applies to the unit, as determined under this part. Background groundwater quality may be established at wells that are not located hydraulically upgradient from the unit if the well meets the requirements of R 299.4906(1)(a).

(8) The number of samples that are collected to establish groundwater quality data shall be consistent with the appropriate statistical procedures that are determined under R 299.4908. For type II landfills, the sampling procedures shall be those specified in R 299.4440 for detection monitoring, R 299.4441 for assessment monitoring, and R 299.4444 for remedial action.

(9) All samples that are obtained shall be representative of the site's groundwater quality. To ensure a representative sample, before a sample for collection and analysis is obtained, each well shall be purged until dry or until not less than 3 times the amount of water in the well casing has been removed. Groundwater monitoring wells shall be sampled immediately after purging where recovery rates allow. Where detection monitoring wells are pumped dry during purging, samples shall be taken within 24 hours.

(10) If nondedicated pumps or mobile sampling equipment is used, the owner or operator shall use the following procedures to minimize the potential for the cross-contamination of samples:

(a) All groundwater-monitoring wells shall be sampled from upgradient to downgradient, except that monitoring wells that are located in areas of known groundwater contamination shall be sampled in order, from the least contaminated well to the most contaminated well.

(b) Each piece of equipment shall be thoroughly cleaned and rinsed with distilled water before use in each monitoring or detection well.

(c) Other procedures that are approved by the department.

(11) The owner and operator of a landfill shall submit all monitoring results to the director or his or her designee not later than 30 days after the end of the calendar quarter. The data must be submitted in a form and format specified by the department.

(12) The owner and operator of a landfill shall sample and analyze groundwater in accordance with the publication entitled "Test Methods for Evaluating Solid Waste, Physical-Chemical Methods," EPA publication SW-846, 3rd edition, which is adopted by reference in R 299.4133, the publication entitled "Standard Methods for the Examination of Water and Wastewater, 19th edition," which is adopted by reference in R 299.4139, or by other methods approved by the director or his or her designee.

Mich. Admin. Code R. 299.4907

1993 AACS; 1999 AACS; 2005 AACS