An owner or operator required to establish a detection monitoring program under this regulation shall, at a minimum, discharge the following responsibilities:

1. A. The owner or operator shall monitor for waste constituents, reaction products, or indicator parameters, such as specific conductance, total organic carbon, or total organic halogen, that provide a reliable indication of the presence of hazardous constituents in ground water, as specified by the Secretary in the facility permit after considering the following factors:

   1. (1) The types, quantities, and concentrations of constituents in wastes managed at the regulated unit;
   2. (2) The mobility, stability, and persistence of waste constituents or their reaction products in the unsaturated zone beneath the waste management area;
   3. (3) The detectability of indicator parameters, waste constituents, and reaction products in ground water; and
   4. (4) The concentrations or values and coefficients of variation of proposed monitoring parameters or constituents in the ground water background;
2. B. The owner or operator shall install a ground water monitoring system at the compliance point, as specified under Regulation .06-1D of this chapter, that is in compliance with Regulation .06-2C(1), D, and F of this chapter;

3. C. The owner or operator shall ensure that a detection monitoring program satisfies the following requirements:

   1. (1) The program includes each chemical parameter and hazardous constituent specified in the permit under §A of this regulation in accordance with Regulation .06-2J and K of this chapter; and
   2. (2) The owner or operator maintains a record of ground water analytical data as measured and in a form necessary for the determination of statistical significance under Regulation .06-3A and B of this chapter;
4. D. The owner or operator shall, at frequencies specified by the Secretary, collect samples and conduct statistical tests to determine whether there is statistically significant evidence of contamination for any parameter or hazardous constituent specified in the permit under §A of this regulation in accordance with Regulations .06-2J and K, and .06-3A of this chapter;
5. E. In complying with the requirements of §D of this regulation, during detection monitoring, the owner or operator shall, at a minimum, collect at least semiannually a sequence of at least four samples from each background and compliance well;
6. F. The owner or operator shall determine the ground water flow rate and direction in the uppermost aquifer at least annually;

7. G. The owner or operator shall determine whether there is statistically significant evidence of contamination for any chemical parameter or hazardous constituent specified in the facility CHS permit under §A of this regulation by:

   1. (1) Making the determination at a frequency specified under §D of this regulation;
   2. (2) Using the method or methods specified in the permit under Regulation .06-3A of this chapter to compare data collected at the compliance point or points to the background ground water quality data; and

   3. (3) Determining whether there is statistically significant evidence of contamination at each monitoring well at the compliance point within a reasonable period of time after completion of sampling, as specified by the Secretary in the permit based on:

      1. (a) The complexity of the statistical test; and
      2. (b) The availability of laboratory facilities to perform the analysis of ground water samples;

8. H. The owner or operator shall comply with the following requirements if the owner or operator determines, in accordance with §G of this regulation, that there is statistically significant evidence of contamination for chemical parameters or hazardous constituents specified under §A of this regulation at any monitoring well at the compliance point:

   1. (1) Notify the Secretary of this finding in writing within 7 days, indicating what chemical parameters or hazardous constituents have shown statistically significant evidence of contamination;
   2. (2) Immediately sample the ground water in all monitoring wells and determine the concentration of all constituents identified in 40 CFR 264, Appendix IX, that are present in ground water;

   3. (3) Except as provided in §H(6) of this regulation, determine the constituents that will form the basis for compliance monitoring by either:

      1. (a) Resampling ground water within 1 month of the time that constituents identified in 40 CFR 264, Appendix IX, are detected under §H(2) of this regulation, repeating the analysis to determine constituent concentrations, and if the results of the second analysis confirm the presence of compounds detected in the first analysis, using those constituents as the basis for compliance monitoring; or
      2. (b) Using the hazardous constituents found during the initial analysis conducted under §H(2) of this regulation as the basis for compliance monitoring;

   4. (4) Within 90 days, submit to the Secretary an application for a permit modification to establish a compliance monitoring program meeting the requirements of Regulation .06-5 of this chapter, including in the application the following information:

      1. (a) For each monitoring well at the compliance point, the concentration of any constituent listed in 40 CFR 264, Appendix IX, that was found in the ground water;
      2. (b) Any proposed changes to the ground water monitoring system at the facility necessary to meet the requirements of Regulation .06-5 of this chapter;
      3. (c) Any proposed changes to the monitoring frequency, sampling, and analysis procedures or methods, or statistical procedures used at the facility necessary to meet the requirements of Regulation .06-5 of this chapter;
      4. (d) For each hazardous constituent found at the compliance point, a proposed concentration limit under Regulation .06-1C(1)(a) or (b) of this chapter, or a notice of intent to seek an alternative concentration limit under Regulation .06-1C(2) of this chapter;

   5. (5) Within 180 days, submit to the Secretary:

      1. (a) All data necessary to justify an alternate concentration limit sought under Regulation .06-1C(2) of this chapter; and

      2. (b) An engineering feasibility plan for a corrective action program necessary to meet the requirements of Regulation .06-6 of this chapter, unless:

         1. (i) All hazardous constituents identified under §H(2) of this regulation are listed in Table 1 of Regulation .06-1C(3) of this chapter and their concentrations do not exceed the respective values given in that table, or
         2. (ii) The owner or operator has sought an alternate concentration limit under Regulation .06-1C(2) of this chapter for each hazardous constituent identified under §H(2) of this regulation;
   6. (6) If the resampling conducted under §H(3)(a) of this regulation does not confirm the initial results, then the owner or operator may remain in detection monitoring, and need not make the submissions required by §H(4) and (5) of this regulation;

9. I. If the owner or operator determines under §G of this regulation that there is statistically significant evidence of contamination for chemical parameters or hazardous constituents specified under §A of this regulation at any monitoring well at the compliance point, the owner or operator may attempt to demonstrate that:

   1. (1) A source other than a regulated unit caused the contamination; or
   2. (2) The finding of statistically significant evidence of contamination resulted from error in sampling, analysis, or statistical evaluation, or from natural variation in ground water;

10. J. The owner or operator shall submit an application for a permit modification within the time specified in §H(4) of this regulation unless a demonstration made under §I of this regulation successfully shows that:

    1. (1) A source other than a regulated unit caused the contamination; or
    2. (2) The finding of statistically significant evidence of contamination resulted from error in sampling, analysis, or statistical evaluation, or from natural variation in ground water;

11. K. In making a demonstration under §I of this regulation, the owner or operator shall:

    1. (1) Notify the Secretary in writing, within 7 days of determining that there is statistically significant evidence of contamination at the compliance point, of the intention to make a demonstration under §I of this regulation;
    2. (2) Within 90 days, submit a report to the Secretary which demonstrates that a source other than a regulated unit caused the contamination, or that the finding of statistically significant evidence of contamination resulted from error in sampling, analysis, or evaluation, or from natural variation in the ground water;
    3. (3) Within 90 days, submit to the Secretary an application for a permit modification to make any appropriate changes to the detection monitoring program at the facility; and
    4. (4) Continue to monitor in accordance with the detection monitoring program established under this regulation;
12. L. If the owner or operator determines that the detection monitoring program no longer satisfies the requirements of this regulation, the owner or operator shall, within 90 days, submit an application for a permit modification to make any appropriate changes to the program.

Authority: Environment Article, Title 7, Subtitle 2, Annotated Code of Maryland

Effective date:

Regulations .01—.18 adopted as an emergency provision effective November 18, 1980 (7:25 Md. R. S-1); adopted permanently effective April 3, 1981 (8:7 Md. R. 642)

Regulations .01, .05G, .06, .08A, .11C, .12D, and .14C amended effective January 18, 1982 (9:1 Md. R. 20)

Regulations .01—.12, .18 amended effective January 31, 1983 (10:2 Md. R. 110)

Regulations .01A, B, .02F, .05D, H, .07C, D, G, H, .08A, .09G, .10D, F, .11A-1, C, E—G, .12A, B, D, D-1, E, G, .13, .14, .15A, .16A, .18 (Appendix IV) amended, .15-1 adopted, .06 repealed and new .06adopted, .10I, .12C-1, and .18 (Appendices VI—XIII) repealed effective February 13, 1984 (11:3 Md. R. 202)

Regulations .01A, .02D, F, .05G, .06A, I, .07A, D, I, .10D, .11B, F, F-1, .12D-1, .14A—C, J, L, .15-1A, D amended, and .01C adopted effective July 30, 1984 (11:15 Md. R. 1330)

Regulation .01A amended effective April 18, 1988 (15:8 Md. R. 1009)

Regulation .02I, J adopted effective April 18, 1988 (15:8 Md. R. 1009)

Regulation .04G amended effective April 18, 1988 (15:8 Md. R. 1009)

Regulation .05A, D amended effective April 18, 1988 (15:8 Md. R. 1009)

Regulation .06A amended effective April 18, 1988 (15:8 Md. R. 1009)

Regulation .06L adopted effective April 18, 1988 (15:8 Md. R. 1009)

Regulation .07B amended effective April 18, 1988 (15:8 Md. R. 1009)

Regulation .07C—J repealed and new C—J adopted effective April 18, 1988 (15:8 Md. R. 1009)

Regulation .08A amended effective April 18, 1988 (15:8 Md. R. 1009)

Regulation .09F, H, and I amended effective April 18, 1988 (15:8 Md. R. 1009)

Regulation .10D, E amended effective April 18, 1988 (15:8 Md. R. 1009)

Regulation .10I adopted effective April 18, 1988 (15:8 Md. R. 1009)

Regulation .11A-1, B, C, E, F, F-1 amended effective April 18, 1988 (15:8 Md. R. 1009)

Regulation .12B, D-1 amended effective April 18, 1988 (15:8 Md. R. 1009)

Regulation .12H adopted effective April 18, 1988 (15:8 Md. R. 1009)

Regulation .13N adopted effective April 18, 1988 (15:8 Md. R. 1009)

Regulation .14B, C amended effective April 18, 1988 (15:8 Md. R. 1009)

Regulation .14P adopted effective April 18, 1988 (15:8 Md. R. 1009)

Regulation .15A amended effective April 18, 1988 (15:8 Md. R. 1009)

Regulation .15-1B, C, and F amended effective April 18, 1988 (15:8 Md. R. 1009)

Regulation .16G adopted effective April 18, 1988 (15:8 Md. R. 1009)

Regulation .10C-1—I recodified to .10D—J

Regulation .11A-1—F recodified to .11B—G

Regulation .11F-1—I recodified to .11H—K

Regulation .12D-1 and D-2 recodified to .12E and F

Regulation .12E—H recodified to .12G—J

Regulation .15-1 recodified to Regulation .16

Regulations .16—.18 recodified to Regulations .17—.19

Appendix I—Appendix V codified as Regulations .20—.24

Chapter recodified from COMAR 10.51.05 to COMAR 26.13.05

Regulation .01A amended effective May 24, 1993 (20:10 Md. R. 853)

Regulation .01C amended effective December 23, 1991 (18:25 Md. R. 2759)

Regulation .02D amended effective December 23, 1991 (18:25 Md. R. 2759)

Regulation .02F amended effective April 1, 1991 (18:6 Md. R. 690); May 24, 1993 (20:10 Md. R. 853)

Regulation .04G amended effective December 23, 1991 (18:25 Md. R. 2759)

Regulation .05B amended effective May 24, 1993 (20:10 Md. R. 853)

Regulation .05D amended effective April 1, 1991 (18:6 Md. R. 690); December 23, 1991 (18:25 Md. R. 2759); May 24, 1993 (20:10 Md. R. 853)

Regulation .05F amended effective December 23, 1991 (18:25 Md. R. 2759)

Regulation .06A amended effective April 1, 1991 (18:6 Md. R. 690)

Regulation .06K amended effective December 23, 1991 (18:25 Md. R. 2759)

Regulation .07A, E, and F amended effective May 24, 1993 (20:10 Md. R. 853)

Regulation .07B, C, E, G, and H amended effective April 1, 1991 (18:6 Md. R. 690)

Regulation .07B, F amended effective December 23, 1991 (18:25 Md. R. 2759)

Regulation .08A amended effective April 1, 1991 (18:6 Md. R. 690)

Regulation .08B amended effective November 9, 1992 (19:22 Md. R. 1991)

Regulation .10 repealed and new Regulations .10—10-7 adopted effective May 24, 1993 (20:10 Md. R. 853)

Regulation .10G amended effective December 23, 1991 (18:25 Md. R. 2759)

Regulation .11D amended effective December 23, 1991 (18:25 Md. R. 2759)

Regulation .14B, N amended effective December 23, 1991 (18:25 Md. R. 2759)

Regulation .16-1 adopted effective April 1, 1991 (18:6 Md. R. 690) (Regulation .16-1 was initially adopted as Regulation .17. The recodification to Regulation .16-1 negated the need for some changes to cross-references shown in the Maryland Register.)

Regulation .20A amended effective December 23, 1991 (18:25 Md. R. 2759)

Chapter revised effective April 11, 1994 (21:7 Md. R. 533)

Regulation .01A amended effective August 28, 1995 (22:17 Md. R. 1321)

Regulation .01 amended effective September 10, 1997 (24:5 Md. R. 413)

Regulation .05F, H amended effective May 5, 1997 (24:9 Md. R. 659)

Regulation .07D amended effective September 10, 1997 (24:5 Md. R. 413)

Regulation .08A amended effective September 10, 1997 (24:5 Md. R. 413)

Regulation .08B amended effective August 28, 1995 (22:17 Md. R. 1321)

Regulation .10A amended effective September 10, 1997 (24:5 Md. R. 413)

Regulation .14N amended effective September 10, 1997 (24:5 Md. R. 413)

Regulation .16A, F amended effective May 8, 1995 (22:9 Md. R. 648)

Regulation .16D amended effective September 10, 1997 (24:5 Md. R. 413)

Regulation .17-1 adopted effective September 10, 1997 (24:5 Md. R. 413)

Regulation .17-2 adopted effective September 10, 1997 (24:5 Md. R. 413)

Regulation .17-3 adopted effective September 10, 1997 (24:5 Md. R. 413)

Regulation .17-4 adopted effective September 10, 1997 (24:5 Md. R. 413)

Regulation .21 repealed effective May 5, 1997 (24:9 Md. R. 659)

Chapter revised effective October 16, 2000 (27:20 Md. R. 1843)

Regulation .01A amended effective November 1, 2002 (29:21 Md. R. 1647); May 1, 2008 (35:8 Md. R. 809); May 3, 2021 (48:9 Md. R. 359); January 13, 2022 (49:1 Md. R. 14); October 1, 2025 (52:17 Md. R. 876)

Regulation .01D amended effective May 1, 2008 (35:8 Md. R. 809)

Regulation .02C amended effective November 1, 2002 (29:21 Md. R. 1647)

Regulation .02C, D amended effective January 13, 2022 (49:1 Md. R. 14)

Regulation .02-1 recodified from COMAR 26.13.06.01 effective October 16, 2000 (27:20 Md. R. 1843)

Regulation .02-2 adopted effective January 13, 2022 (49:1 Md. R. 14)

Regulation .03E, G amended effective May 3, 2021 (48:9 Md. R. 359)

Regulation .04G amended effective May 1, 2008 (35:8 Md. R. 809); October 1, 2025 (52:17 Md. R. 876)

Regulation .05 amended effective September 11, 2006 (33:18 Md. R. 1507)

Regulation .05A, C amended effective May 1, 2008 (35:8 Md. R. 809)

Regulation .05B amended effective November 1, 2002 (29:21 Md. R. 1647); January 13, 2022 (49:1 Md. R. 14)

Regulation .05B, F amended effective May 3, 2021 (48:9 Md. R. 359)

Regulation .05C, D amended effective January 13, 2022 (49:1 Md. R. 14); October 1, 2025 (52:17 Md. R. 876)

Regulation .07 amended effective May 1, 2008 (35:8 Md. R. 809)

Regulation .08B amended effective May 1, 2008 (35:8 Md. R. 809)

Regulation .11 amended effective January 13, 2022 (49:1 Md. R. 14)

Regulation .12 amended effective January 13, 2022 (49:1 Md. R. 14)

Regulation .13L amended effective January 13, 2022 (49:1 Md. R. 14)

Regulation .14 amended effective January 13, 2022 (49:1 Md. R. 14)

Regulation .14N amended effective October 1, 2025 (52:17 Md. R. 876)

Regulation .16F amended effective May 1, 2008 (35:8 Md. R. 809)

Regulation .17-3E amended effective November 1, 2002 (29:21 Md. R. 1647)

Regulation .18 adopted effective May 1, 2008 (35:8 Md. R. 809)

Regulation .18-1 adopted effective May 1, 2008 (35:8 Md. R. 809)

Regulation .18-2 adopted effective May 1, 2008 (35:8 Md. R. 809)

Regulation .18-3 adopted effective May 1, 2008 (35:8 Md. R. 809)

Regulation .21 adopted effective May 1, 2008 (35:8 Md. R. 809)