OAR 340-095-0040: Groundwater Monitoring and Corrective Action

(1) Groundwater: (a) Each non-municipal land disposal site permittee shall ensure that: (A) The introduction of any substance from the land disposal site into an underground drinking water source does not result in a violation of any applicable federal or state drinking water rules or regulations beyond the solid waste boundary of the land disposal site or an alternative boundary specified by the Department; (B) The introduction of any substance from the land disposal site into an aquifer does not impair the aquifer’s recognized beneficial uses, beyond the solid waste boundary of the land disposal site or an alternative boundary specified by the Department, consistent with OAR 340, division 40 and any applicable federal or state rules or regulations. (b) Where monitoring is required, monitoring wells shall be placed at Department-approved locations between the solid waste boundary and the property line if adequate room exists; (c) The Department may specify an alternative boundary based on a consideration of all of the following factors: (A) The hydrogeological characteristics of the facility and surrounding land; (B) The volume and physical and chemical characteristics of the leachate; (C) The quantity and directions of flow of groundwater; (D) The proximity and withdrawal rates of groundwater users; (E) The availability of alternative drinking water supplies; (F) The existing quality of the groundwater including other sources of contamination and their cumulative impacts on the groundwater; and (G) Public health, safety, and welfare effects. (2) Monitoring: (a) Where the Department finds that a non-municipal land disposal site’s location and geophysical condition indicate that there is a reasonable probability of potential adverse effects on public health or the environment, the Department may require a permittee to provide monitoring wells at Department-approved locations and depths to determine the effects of the non-municipal land disposal site on groundwater; (b) If the Department determines that monitoring wells are required at a non-municipal land disposal site, the permittee shall provide and maintain the wells at the locations specified by the Department and shall submit a copy of the geologic log and record of well construction to the Department within 30 days of completion of construction; (c) Where the Department determines that self-monitoring is practicable, the Department may require that the permittee collect and analyze samples of surface water and/or groundwater, at intervals specified and in a manner approved by the Department, and submit the results in a format and within a time frame specified by the Department; (d) The Department may require permittees who do self-monitoring to periodically split samples with the Department for the purpose of quality control. (3) Corrective action. Notwithstanding OAR 340-093-0030(22), the Department may require action to remediate releases of constituents above the levels specified in OAR 340 division 40. This authority is in addition to any other authority granted by law.