Section NR 507.18 - Baseline groundwater quality sampling An applicant for a proposed facility for all its monitoring wells and the owner or operator of an existing facility for its designated Subtitle D wells shall establish baseline groundwater quality in accordance with subs. (1) to (3). Owners or operators shall establish baseline groundwater quality at all new or replacement groundwater monitoring wells in accordance with sub. (4). The department may require the owners or operators of other facilities at which monitoring is required to establish baseline groundwater quality in accordance with sub. (4). Collection, handling and analysis of groundwater monitoring samples specified in subs. (1) to (4) shall be performed in accordance with ss. NR 507.16 and 507.17.
(1) BASELINE GROUNDWATER QUALITY FOR DETECTION MONITORING PARAMETERS EXCEPT VOCS. (a) Baseline groundwater quality shall be established at all wells that were installed outside the proposed limits of filling to evaluate the proposed facility. Samples shall be analyzed for each detection monitoring parameter as appropriate for the particular waste types accepted at the landfill. Chapter NR 507 Appendix I, Tables 1, 1A, and 2 indicate which parameters shall be analyzed for each waste type. The department may require additional parameters based on the waste types and waste characteristics accepted at the landfill.(b) The owner or operator shall obtain and analyze a minimum of 8 samples to determine baseline groundwater quality for the parameters required under this subsection. For a proposed facility, a minimum of 4 samples, with at least 30 days between sampling rounds, shall be taken and analyzed and the results shall be submitted with the feasibility report. The remaining samples shall be taken with at least 30 days between sampling rounds and the results shall be submitted with the plan of operation unless otherwise approved in writing by the department.(2) BASELINE GROUNDWATER QUALITY FOR PUBLIC HEALTH AND WELFARE PARAMETERS NOT INCLUDED AS DETECTION MONITORING PARAMETERS IN SUB. (1). (a) Unless otherwise specified by the department, baseline groundwater quality shall be established at all wells outside the proposed limits of filling which were installed to evaluate the proposed facility. Baseline water quality for these wells shall be established for the public health and welfare groundwater quality standards listed in ch. NR 507 Appendix I, Table 3.(b) For a proposed facility, a minimum of 4 samples, with at least 30 days between sampling rounds, shall be collected and analyzed and the results shall be submitted with the feasibility report. Four additional samples, with at least 30 days between sampling rounds, shall be collected and analyzed for any parameter listed in ch. NR 507 Appendix I, Table 3 from any well which meets one or more of the following criteria: 1. One of the initial 4 sample values attains or exceeds the ES for that parameter.2. Two or more of the initial 4 sample values attains or exceeds the PAL for that parameter.3. The average of the initial 4 sample values attains or exceeds the PAL for that parameter.(c) If additional samples are required under par. (b), the results of the 4 additional samples shall be submitted in the plan of operation and in accordance with s. NR 507.26 (3).(3) BASELINE GROUNDWATER QUALITY FOR VOCS. (a) Baseline groundwater quality shall be established for all VOCs listed in ch. NR 507 Appendix III, at all monitoring wells outside the proposed limits of filling. Landfills designed to accept CCR and CCR landfills are exempt from baseline groundwater quality monitoring for VOCs.(b) Samples shall be collected for VOC analysis from each well at the same time as the first and second sampling rounds for the other detection monitoring parameters. If any well has VOC parameters in concentrations above their limit of detection in either of the first 2 sampling rounds, that well shall be sampled for VOCs 2 additional times for a total of 4 sampling rounds. The results shall be submitted with the feasibility report and in accordance with s. NR 507.26(3).(4) BASELINE GROUNDWATER QUALITY AT NEW OR REPLACEMENT MONITORING WELLS. All new or replacement groundwater monitoring wells installed after July 1, 1996, shall be sampled on a semi-annual basis beginning with the sampling event following installation for the parameters specified in subs. (1) to (3) to establish baseline groundwater quality. The results shall be submitted in accordance with s. NR 507.26 (3). The department may waive the requirement to establish baseline groundwater quality monitoring for a replacement well which is established in the same environment and proximity as the well being replaced. (5) BASELINE GROUNDWATER QUALITY SAMPLING AT CCR WELLS.(a) Baseline groundwater quality shall be established by the owner or operator of a CCR landfill at all CCR wells installed outside the proposed limits of filling to evaluate groundwater quality in the uppermost aquifer beneath the CCR landfill as provided in par. (b). Samples shall be analyzed for each monitoring parameter as indicated under ch. NR 507 Appendix I, Tables 1A and 3 for detection and baseline monitoring for CCR wells.(b) The owner or operator of a CCR landfill shall obtain, analyze, and submit the results from a minimum of 8 groundwater quality samples from each CCR well to the department to determine baseline groundwater quality for the parameters required under this subsection. The information shall be submitted as part of the plan of operation modification required under s. NR 514.045 or the feasibility report for a proposed landfill.(c) The department may not approve a CCR landfill at a location where a preventive action limit or enforcement standard adopted under s. NR 140.10 or 140.12 has been attained or exceeded in the baseline monitoring sampling results unless the department grants an exemption to those standards in accordance with s. NR 140.28 as part of a CCR landfill feasibility determination, plan of operation approval, or plan of operation modification approval under s. NR 514.045.(d) A preventive action limit for lithium shall be established by the department at each CCR well in accordance with s. NR 140.20 (2) (c) set at the background water quality plus 3 standard deviations.Wis. Admin. Code Department of Natural Resources NR 507.18
Cr. Register, June, 1996, No. 486, eff. 7-1-96; corrections in (1) (a), (2) (a), (3) (a) made under s. 13.92(4) (b) 7, Stats., Register April 2013 No. 688.Amended by, CR 21-076: am. (1) (a), (3) (a), cr. (5) Register July 2022 No. 799, eff. 8/1/2022.