Rule 3745-525-900 | Groundwater monitoring and corrective action applicability, 40 C.F.R. 257.90.
(A) Applicability. All CCR units are subject to the groundwater monitoring and corrective action requirements under rules 3745-525-900 to 3745-525-970 of the Administrative Code.
(B) Initial timeframes.
(1) Existing CCR landfills and existing CCR surface impoundments. Not later than October 17, 2017, the owner or operator of the CCR unit shall be in compliance with the following groundwater monitoring requirements:
(a) Install the groundwater monitoring system as required by rule 3745-525-910 of the Administrative Code.
(b) Develop the groundwater sampling and analysis program to include selection of the statistical procedures to be used for evaluating groundwater monitoring data as required by rule 3745-525-920 of the Administrative Code.
(c) Initiate the detection monitoring program to include obtaining a minimum of eight independent samples for each background and downgradient well as required by paragraph (B) of rule 3745-525-930 of the Administrative Code.
(d) Begin evaluating the groundwater monitoring data for statistically significant increases over background levels for the constituents listed in appendix A to this rule as required by rule 3745-525-930 of the Administrative Code.
(2) New CCR landfills, new CCR surface impoundments, and all lateral expansions of CCR units. Prior to initial receipt of CCR by the CCR unit, the owner or operator shall be in compliance with the groundwater monitoring requirements specified in paragraphs (B)(1)(a) and (B)(1)(b) of this rule. In addition, the owner or operator of the CCR unit shall initiate the detection monitoring program to include obtaining a minimum of eight independent samples for each background well as required by paragraph (B) of rule 3745-525-930 of the Administrative Code.
(C) Requirement to conduct groundwater monitoring and corrective action. Once a groundwater monitoring system and groundwater monitoring program has been established at the CCR unit as required by this chapter, the owner or operator shall conduct groundwater monitoring and, if necessary, corrective action throughout the active life and post-closure care period of the CCR unit.
(D) Responding to a release from a CCR unit. In the event of a release from a CCR unit, the owner or operator shall immediately take all necessary measures to control the source of releases so as to reduce or eliminate, to the maximum extent feasible, further releases of contaminants into the environment. The owner or operator of the CCR unit shall comply with all applicable requirements in rules 3745-525-950 to 3745-525-970 of the Administrative Code.
(E) Annual groundwater monitoring and corrective action report. For existing CCR landfills and existing CCR surface impoundments, not later than January 31, 2018, and annually thereafter, the owner or operator shall prepare an annual groundwater monitoring and corrective action report. For new CCR landfills, new CCR surface impoundments, and all lateral expansions of CCR units, the owner or operator shall prepare the initial annual groundwater monitoring and corrective action report not later than January thirty-first of the year following the calendar year a groundwater monitoring system has been established for such CCR unit as required by this chapter, and annually thereafter. For the preceding calendar year, the annual report shall document the status of the groundwater monitoring and corrective action program for the CCR unit, summarize key actions completed, describe any problems encountered, discuss actions to resolve the problems, and project key activities for the upcoming year. For purposes of this rule, the owner or operator has prepared the annual report when the report is placed in the facility's operating record as required by paragraph (H)(1) of rule 3745-525-50 of the Administrative Code. At a minimum, the annual groundwater monitoring and corrective action report shall contain the following information, to the extent available:
(1) A map, aerial image, or diagram showing the CCR unit and all background (or upgradient) and downgradient monitoring wells, to include the well identification numbers, that are part of the groundwater monitoring program for the CCR unit.
(2) Identification of any monitoring wells that were installed or decommissioned during the preceding year, along with a narrative description of why those actions were taken.
(3) In addition to all the monitoring data obtained under rules 3745-525-900 to 3745-525-970 of the Administrative Code, a summary including the number of groundwater samples that were collected for analysis for each background and downgradient well, the dates the samples were collected, and whether the sample was required by the detection monitoring or assessment monitoring programs.
(4) A narrative discussion of any transition between monitoring programs (e.g., the date and circumstances for transitioning from detection monitoring to assessment monitoring in addition to identifying the constituent detected at a statistically significant increase over background levels).
(5) Other information required to be included in the annual report as specified in rules 3745-525-900 to 3745-525-970 of the Administrative Code.
(6) A section at the beginning of the annual report that provides an overview of the current status of groundwater monitoring and corrective action programs for the CCR unit. At a minimum, the summary shall specify all of the following:
(a) At the start of the current annual reporting period, whether the CCR unit was operating under the detection monitoring program in rule 3745-525-930 of the Administrative Code or the assessment monitoring program in rule 3745-525-940 of the Administrative Code.
(b) At the end of the current annual reporting period, whether the CCR unit was operating under the detection monitoring program in rule 3745-525-930 of the Administrative Code or the assessment monitoring program in rule 3745-525-940 of the Administrative Code.
(c) If it was determined that there was a statistically significant increase over background for one or more constituents listed in appendix A to this rule pursuant to paragraph (E) of rule 3745-525-930 of the Administrative Code:
(i) Identify those constituents listed in appendix A to this rule and the names of the monitoring wells associated with such an increase.
(ii) Provide the date when the assessment monitoring program was initiated for the CCR unit.
(d) If it was determined that there was a statistically significant level above the groundwater protection standard for one or more constituents listed in appendix B to this rule pursuant to paragraph (G) of rule 3745-525-940 of the Administrative Code include all of the following:
(i) Identify those constituents listed in appendix B to this rule and the names of the monitoring wells associated with such an increase.
(ii) Provide the date when the assessment of corrective measures was initiated for the CCR unit.
(iii) Provide the date when the public meeting was held for the assessment of corrective measures for the CCR unit.
(iv) Provide the date when the assessment of corrective measures was completed for the CCR unit.
(e) Whether a remedy was selected pursuant to rule 3745-525-960 of the Administrative Code during the current annual reporting period, and if so, the date of remedy selection.
(f) Whether remedial activities were initiated or are ongoing pursuant to rule 3745-525-970 of the Administrative Code during the current annual reporting period.
(F) The owner or operator of the CCR unit shall comply with the recordkeeping requirements specified in paragraph (H) of rule 3745-525-50 of the Administrative Code, the notification requirements specified in paragraph (H) of rule 3745-525-60 of the Administrative Code, and the internet requirements specified in paragraph (H) of rule 3745-525-70 of the Administrative Code.
Last updated October 1, 2026 at 12:16 PM
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