Section 335.164 - Detection Monitoring ProgramAn owner or operator required to establish a detection monitoring program must, at a minimum, discharge the following responsibilities:
(1) The owner or operator must monitor for indicator parameters (e.g., 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. The commission will specify the parameters or constituents to be monitored in the facility permit, after considering the following factors:(A) the types, quantities, and concentrations of constituents in 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;(C) the detectability of indicator parameters, waste constituents, and reaction products in groundwater; and(D) the concentrations or values and coefficients of variation of adopted monitoring parameters or constituents in the groundwater background.(2) The owner or operator must install a groundwater monitoring system at the compliance point as specified under § 335.161 of this title (relating to Point of Compliance). The groundwater monitoring system must comply with §335.163(1)(B), (2), and (3) of this title (relating to General Groundwater Monitoring Requirements).(3) The owner or operator must conduct a groundwater monitoring program for each chemical parameter and hazardous constituent specified in its permit pursuant to paragraph (1) of this section in accordance with § 335.163(7) of this title. The owner or operator must maintain a record of groundwater analytical data as measured and in a form necessary for the determination of statistical significance under § 335.163(8) of this title.(A) The owner or operator must comply with § 335.163(7) of this title in developing the data base used to determine background values.(B) The owner or operator must express background values in a form necessary for the determination of statistically significant increases under § 335.163(8) of this title.(C) In taking samples used in the determination of background values, the owner or operator must use a groundwater monitoring system that complies with §335.163(1)(A), (2), and (3) of this title.(4) The commission 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 permit under paragraph (1) of this section in accordance with § 335.163(7) of this title.(5) The owner or operator must determine the groundwater flow rate and direction in the uppermost aquifer at least annually.(6) The owner or operator must determine whether there is statistically significant evidence of contamination for any chemical parameter or hazardous constituent specified in the permit pursuant to paragraph (1) of this section at a frequency specified under paragraph (4) of this section.(A) In determining whether statistically significant evidence of contamination exists, the owner or operator must use the method(s) specified in the permit under § 335.163(8) of this title. These method(s) must compare data collected at the compliance point(s) to the background groundwater quality data.(B) The owner or operator must determine 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. The commission will specify in the facility permit what period of time is reasonable, after considering the complexity of the statistical test and the availability of laboratory facilities to perform the analysis of groundwater samples.(7) If the owner or operator determines pursuant to paragraph (6) of this section that there is statistically significant evidence of contamination for chemical parameters or hazardous constituents specified pursuant to paragraph (1) of this section at any monitoring well at the compliance point, he must: (A) notify the executive director of this finding in writing within seven days. The notification must indicate what chemical parameters or hazardous constituents have shown statistically significant evidence of contamination;(B) immediately sample the groundwater in all monitoring wells that exhibit statistically significant evidence of contamination and determine whether constituents in the list of Appendix IX of 40 Code of Federal Regulations Part 264 are present, and if so, in what concentration. However, the executive director, on a discretionary basis, may allow sampling for a site-specific subset of constituents from the Appendix IX list and other representative/related waste constituents;(C) For any Appendix IX compounds found in the analysis pursuant to subparagraph (B) of this paragraph, the owner or operator may resample within one month or an alternative site-specific schedule approved by the executive director and repeat the analysis for those compounds detected. If the results of the second analysis confirm the initial results, then these constituents will form the basis for compliance monitoring. If the owner or operator does not resample for the compounds found in subparagraph (B) of this paragraph, the hazardous constituents found during this initial Appendix IX analysis will form the basis for compliance monitoring.(D) within 90 days, submit to the executive director an application for a permit amendment or modification to establish a compliance monitoring program meeting the requirements of § 335.165 of this title (relating to Compliance Monitoring Program). The application must include the following information:(i) an identification of the concentration of any Appendix IX constituent detected in the groundwater at each monitoring well that exhibits statistically significant evidence of contamination at the compliance point;(ii) any adopted changes to the groundwater monitoring system at the facility necessary to meet the requirements of § 335.165 of this title;(iii) any adopted 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 § 335.165 of this title; and(iv) for each hazardous constituent detected at the compliance point, a adopted concentration limit under § 335.160(a)(1) or (2) of this title (relating to Concentration Limits), or a notice of intent to seek an alternate concentration limit under § 335.160(b) of this title;(E) within 180 days, submit to the executive director: (i) all data necessary to justify an alternate concentration limit sought under § 335.160(b) of this title;(ii) an engineering feasibility plan for a corrective action program necessary to meet the requirements of § 335.166 of this title (relating to Corrective Action Program), unless: (I) all hazardous constituents identified under subparagraph (b) of this paragraph are listed in Table 1 of § 335.160 of this title and their concentrations do not exceed the respective values given in that table; or(II) the owner or operator has sought an alternate concentration limit under § 335.160(b) of this title for every hazardous constituent identified under subparagraph (B) of this paragraph.(F) if the owner or operator determines, pursuant to paragraph (6) of this section, that there is a statistically significant difference for chemical parameters or hazardous constituents specified pursuant to paragraph (1) of this section at any monitoring well at the compliance point, he or she may demonstrate that a source other than a regulated unit caused the contamination or that the detection is an artifact caused by an error in sampling, analysis, or statistical evaluation or natural variation in the groundwater. The owner operator may make a demonstration under this paragraph in addition to, or in lieu of, submitting a permit amendment or modification application under subparagraph (D) of this paragraph; however, the owner or operator is not relieved of the requirement to submit a permit amendment or modification application within the time specified in subparagraph (D) of this paragraph unless the demonstration made under this paragraph 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 under this paragraph, the owner or operator must:(i) notify the executive director in writing within seven days of determining statistically significant evidence of contamination at the compliance point that he intends to make a demonstration under this paragraph;(ii) within 90 days, submit a report to the executive director which demonstrates that a source other than a regulated unit caused the contamination or that the contamination resulted from error in sampling, analysis, or evaluation;(iii) within 90 days, submit to the executive director an application for a permit amendment or modification to make any appropriate changes to the detection monitoring program at the facility; and(iv) continue to monitor in accordance with the detection monitoring program established under this section.(8) If the owner or operator determines that the detection monitoring program no longer satisfies the requirements of this section, he must, within 90 days, submit an application for a permit amendment or modification to make any appropriate changes to the program.30 Tex. Admin. Code § 335.164
The provisions of this §335.164 adopted to be effective May 28, 1986, 11 TexReg 2347; amended to be effective August 4, 1989, 14 TexReg 3532; amended to be effective October 29, 1990, 15 TexReg 6017; amended to be effective March 1, 1996, 21 TexReg 1425; amended to be effective November 15, 2001, 26 TexReg 9135; amended to be effective October 29, 2009, 34 TexReg 7321