Detection Monitoring Program

An owner or operator required to establish a detection monitoring program pursuant to 310 CMR 30.661 and 30.662 shall, at a minimum, comply with the following: (1) The owner or operator shall monitor for all indicator parameters (e.g., pH, specific conductance, total organic carbon, or total organic halogen), waste constituents, or reaction products that provide a reliable indication of the presence of hazardous constituents in groundwater. In the facility license, the Department shall specify the parameters or constituents to be monitored after considering: (a) The types, quantities, and concentrations of constituents in hazardous wastes managed at the regulated unit; (b) The mobility, stability, and persistence of waste constituents or their reaction products in the unsaturated zone beneath the waste management area, as described in 310 CMR 30.669(2); (c) The detectability of indicator parameters, waste constituents, and reaction products in groundwater; and (d) The concentrations or values, and in all cases the coefficients of variation of proposed monitoring parameters or constituents in the groundwater background. (2) The owner or operator shall install a groundwater monitoring system at compliance points as specified pursuant to 310 CMR 30.669. The groundwater monitoring system shall be in compliance with 310 CMR 30.663(1)(b), (2) and (3). (3) The owner or operator shall conduct a ground-water monitoring program for each chemical parameter and hazardous constituent specified in the license pursuant to 310 CMR 30.664(1) in accordance with 310 CMR 30.663(7). The owner or operator shall maintain a record of ground-water analytical data as measured and in a form necessaryfor determination of statistical significance pursuant to 310 CMR 30.663(7). (4) The Department will specify the frequencies for collecting samples and conducting statistical tests to determine whether there is statistically significant evidence of contamination for any parameter or hazardous constituent specified in the license pursuant to 310 CMR 30.664(1) in accordance with 310 CMR 30.663(7). A sequence of at least four samples from each well (background and compliance wells) shall be collected at least semiannually during detection monitoring. (5) The owner or operator shall determine the groundwater flow rate and direction in the uppermost aquifer at least annually. (6) The owner or operator shall determine whether there is statistically significant evidence of contamination for any chemical parameter or hazardous constituent specified in the license pursuant to 310 CMR 30.664(1) at a frequency specified pursuant to 310 CMR 30.664(4). (a) In determining whether statistically significant evidence of contamination exists, the owner or operator shall use the method(s) specified in the license pursuant to 310 CMR 30.663(8). These methods shall compare data collected at the compliance point(s) to the background ground-water quality data. (b) The owner or operator shall determine whether there is statistically significant evidence of contamination at each monitoring well as the compliance point within a reasonable period of time after completion of sampling. The Department will specify in the facility license what period of time is reasonable, after considering complexity of the statistical test and the availability of laboratory facilities to perform the analysis of ground-water samples. (7) If the owner or operator determines pursuant to 310 CMR 30.664(6) that there is statistically significant evidence of contamination for chemical parameters or hazardous constituents specified pursuant to 310 CMR 30.664(1) at any monitoring well at the compliance point, the owner or operator shall: (a) Notify the Department of this finding in writing within seven days. The notification shall indicate what chemical parameters or hazardous constituents have shown statistically significant evidence of contamination. (b) Immediately sample the ground water in all monitoring wells and determine whether constituents in 310 CMR 30.161 are present and, if so, in what concentration. (c) For any 310 CMR 30.161 compounds found in the analysis pursuant to 310 CMR 30.664(7)(b), the owner or operator may resample within one month and repeat the analysis for those compounds detected. If the results of the second analysis confirm the initial results, then these constituents shall form the basis for compliance monitoring. If the owner or operator does not resample for compounds found pursuant to 310 CMR 30.664(7)(b), the hazardous constituents found during the initial analysis for compounds in 310 CMR 30.161 shall form the basis for compliance monitoring. (d) Within 90 days, submit to the Department an application for a license modification to establish a compliance monitoring program meeting the requirements of 310 CMR 30.671. The application shall include the following information: 1. An identification of the concentration or any 310 CMR 30.161 constituent detected in the ground water at each monitoring well at the compliance point; 2. Any proposed changes to the ground-water monitoring system at the facility necessary to meet the requirements of 310 CMR 30.671; 3. Any proposed additions or changes to the monitoring frequency, sampling and analysis procedures or methods, or statistical methods used at the facility necessary to meet the requirements of 310 CMR 30.671; 4. For each hazardous constituent detected at the compliance point, a proposed concentration limit pursuant to 310 CMR 30.667(1)(a) or (b), or a notice of intent to seek an alternate concentration limit pursuant to 310 CMR 30.667(2); and (e) Within 180 days, submit to the Department: 1. All data necessary to justify an alternate concentration limit sought pursuant to 310 CMR 30.667(2); and 2. An engineering feasibility plan for a corrective action program necessary to meet the requirements of 310 CMR 30.672, unless: a. All hazardous constituents identified pursuant to 310 CMR 30.664(7)(b) are listed in 310 CMR 30.668 and their concentrations do not exceed the respective values given in Table 30.668; or b. The owner or operator has sought an alternate concentration limit pursuant to 310 CMR 30.667(2) for every hazardous constituent identified pursuant to 310 CMR 30.664(7)(b). (f) If the owner or operator determines, pursuant to 310 CMR 30.664(6), that there is a statisticallysignificant difference for chemical parameters or hazardous constituents specified pursuant to 310 CMR 30.664(1) at any monitoring well at the compliance point, the owner or operator may demonstrate that a source other than a regulated unit has caused the contamination or that the detection is an artifact caused by error in sampling, analysis, or statistical evaluation or natural variation in ground water. The owner or operator may make a demonstration pursuant to 310 CMR 30.664(7)(f) in addition to, or in lieu of, submitting a license modification application pursuant to 310 CMR 30.664(7)(d); however, the owner or operator is not relieved of the requirement to submit a license modification application within the time specified in 310 CMR 30.664(7)(d) unless the demonstration made pursuant to 310 CMR 30.664(7)(f) successfully shows that a source other than a regulated unit caused the increase, or that the increase resulted from error in sampling, analysis or evaluation. In making a demonstration pursuant to 310 CMR 30.664(7)(f), the owner or operator shall: 1. Notify the Department in writing within seven days of determining statistically significant evidence of contamination at the compliance point that the owner or operator intends to make a demonstration pursuant to 310 CMR 30.664(7)(f); 2. Within 90 days, submit a report to the Department which demonstrates that a source other than a regulated unit caused the contamination or that the contamination resulted from an error in sampling, analysis, or evaluation; 3. Within 90 days, submit to the Department an application for a license modification to make any appropriate changes to the detection monitoring program; and 4. Continue to monitor in accordance with the detection monitoringprogram established pursuant to 310 CMR 30.664. (8) If the owner or operator determines that the detection monitoring program no longer satisfies the requirements of 310 CMR 30.664, the owner or operator shall, within 90 days, submit an application for license modification to make any appropriate changes to the program.