(a) The owner or operator shall sample and analyze the groundwater monitoring system for the constituents listed in 40 Code of Federal Regulations (CFR) Part 258, Appendix I, effective July 14, 2005, herein adopted by reference.
(b) The executive director may delete any of the constituents listed in 40 CFR Part 258, Appendix I for a municipal solid waste management unit if it can be documented that the removed constituents are not reasonably expected to be in or derived from the waste contained in the unit.
(c) The executive director may establish an alternative list of inorganic indicator constituents for a municipal solid waste management unit in lieu of some or all of the heavy metals (constituents (1) - (15) in the table located in 40 CFR Part 258, Appendix I) if the alternative constituents provide a reliable indication of inorganic releases from the municipal solid waste management unit to the groundwater. The executive director may also add inorganic or organic constituents to those to be tested if they are reasonably expected to be in or derived from the waste contained in the unit or if they are likely to provide a useful indication of releases from the municipal solid waste management unit to the groundwater. In determining alternative or additional constituents, the executive director shall consider the following factors:
  (1) the types, concentrations, quantities, and persistence of waste constituents in wastes at the municipal solid waste management unit;
  (2) the mobility, stability, and persistence of waste constituents or their reaction products in the unsaturated and saturated zones adjacent to or beneath the municipal solid waste management unit;
  (3) the detectability of indicator constituents, waste constituents, and reaction products in the groundwater; and
  (4) the concentrations and coefficients of variation of monitoring parameters or constituents in the groundwater background.

Source Note: The provisions of this §330.419 adopted to be effective March 27, 2006, 31 TexReg 2502