(11) If the owner or operator determines that there is a statistically significant increase over background in any parameter or constituent at any monitoring well at the compliance point, the owner or operator shall:(a) within 14 days of the completion of the statistical analysis of the sample results and within 30 days of the receipt of the sample results, enter the information in the operating record and notify the director of this finding in writing. The notification shall indicate what parameters or constituents have shown statistically significant changes; and
(b) immediately resample the groundwater in each monitoring well, both background and downgradient, or in a subset of wells specified by the director, and determine:
(i) the concentration of the constituents listed in Section R315-308-4, including additional constituents that may have been identified in the approved groundwater monitoring plan;
(ii) if there is a statistically significant increase over background of any parameter or constituent in any monitoring well at the compliance point; and
(iii) notify the director in writing within seven days of the completion of the statistical analysis of the sample results.
(c) The owner or operator may demonstrate that a source other than the solid waste disposal facility caused the contamination or that the statistically significant change resulted from error in sampling, analysis, statistical evaluation, or natural variation in groundwater quality. A report documenting this demonstration shall be certified by a qualified groundwater scientist and approved by the director and entered in the operating record. If a successful demonstration is made and documented, the owner or operator may continue monitoring as specified in Subsection R315-308-2(5)(b).
(12) If, after 90 days, a successful demonstration as stipulated in Subsection R315-308-2(11)(c) is not made, the owner or operator shall initiate the assessment monitoring program required as follows:
(a) Within 14 days of the determination that a successful demonstration is not made, take one sample from each downgradient well and analyze for the constituents listed as Appendix II in 40 CFR Part 258, 2001 ed., which is incorporated by reference.
(b) For any constituent detected from Appendix II, 40 CFR Part 258, in the downgradient wells a minimum of four independent samples from the upgradient and four independent samples from each downgradient well shall be collected, analyzed, and statistically evaluated to establish background concentration levels for the constituents.
(c) Within 14 days of the completion of the statistical analysis of the sample results and within 30 days of the receipt of the sample results, place a notice in the operation record and notify the director in writing identifying the Appendix II, 40 CFR Part 258, constituents and their concentrations that have been detected as well as background levels. The director shall establish a groundwater quality protection standard pursuant to Subsection R315-308-2(6) for any Appendix II, 40 CFR Part 258, constituent detected in the downgradient wells.
(d) The owner or operator shall thereafter resample:
(i) at a minimum, each downgradient well on a quarterly basis for the constituents in Section R315-308-4, or the alternative list that may have been approved as part of the permit, and for those constituents detected from Appendix II, 40 CFR Part 258;
(ii) the downgradient wells on an annual basis for the constituents in Appendix II, 40 CFR Part 258; and
(iii) statistically analyze the results of the groundwater monitoring samples.
(e) The director may specify additional or fewer constituents depending upon the nature of the groundwater or the waste on a site specific basis considering:
(i) the types, quantities, and concentrations of constituents in wastes managed at the solid waste management unit;
(ii) the mobility, stability, and persistence of waste constituents or their reaction products in the unsaturated zone beneath the solid waste management unit;
(iii) the detectability of indicator parameters, waste constituents, and reaction products in the groundwater; and
(iv) the background concentration or values and coefficients of variation of monitoring parameters or constituents in the groundwater.
(f) If after two consecutive sampling events, the concentrations of the constituents being analyzed in Subsection R315-308-2(12)(d)(i) are shown to be at or below established background values, the owner or operator shall notify the director of this finding and may, upon the approval of the director, return to the monitoring schedule and constituents as specified in Subsection R315-308-2(5)(b).
(13) If one or more constituents from Section R315-308-4 or the approved alternative list, or from those detected from Appendix II, 40 CFR Part 258, are detected at statistically significant levels above the groundwater quality protection standard as established pursuant to Subsection R315-308-2(6) in any sampling event, the owner or operator shall:
(a) within 14 days of the receipt of this finding, place a notice in the operating record identifying the constituents and concentrations that have exceeded the groundwater quality standard. Within that period, the owner or operator shall also notify the director and the appropriate local governmental and local health officials that the groundwater quality standard has been exceeded;
(b) characterize the nature and extent of the release by installing additional monitoring wells as necessary;
(c) install at least one additional monitoring well at the facility boundary in the direction of contaminant migration and sample this well and analyze the sample for the constituents in Section R315-308-4 or the approved alternative list and the detected constituents from Appendix II, 40 CFR Part 258; and
(d) notify each person who owns the land or resides on the land that directly overlies any part of the plume of contamination if contaminants have migrated off-site as indicated by sampling of wells in accordance with Subsections R315-308-2(13)(b) and (13)(c).
