Section 40.0045 - Remedial Wastewater Discharges to the Ground Surface or Subsurface and/or Groundwater(1)Requirement for All Discharges to the Ground Surface or Subsurface and/or Groundwater. Any person performing response actions at a disposal site in accordance with M.G.L. c. 21E and 310 CMR 40.0000 may discharge Remedial Wastewater to the ground surface or subsurface and/or groundwater, provided such discharge:(a) does not erode or otherwise impair the functioning of the surficial and subsurface soils, infiltrate underground utilities, building interiors or subsurface structures, result in groundwater mounding within two feet of the ground surface, or result in flooding of, or breakout to the ground surface; and(b) otherwise complies with M.G.L. c. 21E and 310 CMR 40.0000.(2) Any person performing response actions at a disposal site in accordance with M.G.L. c. 21E and 310 CMR 40.0000 may discharge Remedial Wastewater to the ground surface or subsurface and/or groundwater without a permit from the Department pursuant to M.G.L. c. 21, § 43, and 314 CMR 5.00, the Massachusetts Ground Water Discharge Permit Program, provided the discharge is exempt from such permitting requirements under 314 CMR 5.05.(3)Requirements for Downgradient and Off-Site Discharges. (a) Except as provided for in 310 CMR 40.0045(5) through (7), any person performing response actions at a disposal site in accordance with M.G.L. c. 21E and 310 CMR 40.0000 may discharge Remedial Wastewater to the ground surface or subsurface and/or groundwater, at a location either downgradient of the point of withdrawal or outside of the boundaries of the disposal site, provided:1. the OHM concentrations discharged are below the applicable Reportable Concentrations established by 310 CMR 40.0300 and 40.1600, or, for OHM for which there is no applicable Reportable Concentration, the concentration discharged is below background or a concentration determined by a site-specific evaluation not to exacerbate existing conditions;2. groundwater downgradient of the point of discharge is monitored at regular intervals of three months to detect any migration of oil and/or hazardous material at or from the disposal site;3. the discharge from the treatment works is monitored after initial operation and any modification (e.g., on the 1st, 3rd, 6th day, and weekly thereafter for the rest of the first month of operation), and at regular intervals of 30 days thereafter;4. the discharge is not made to a location at which the concentrations of oil and/or hazardous material in the groundwater are significantly lower than the concentrations of oil and/or hazardous material in the discharge; and5. the discharge does not exacerbate existing conditions, or prevent or impair the performance of remedial actions, at the disposal site.(b) The discharge of Remedial Wastewater containing hazardous waste at a point outside of the boundaries of the disposal site is prohibited, except as provided by 310 CMR 30.000: Hazardous Waste.(4)Requirements for Upgradient Discharges. Except as provided for in 310 CMR 40.0045(5) through (7), any person performing response actions at a disposal site in accordance with M.G.L. c. 21E and 310 CMR 40.0000 may discharge Remedial Wastewater to the ground surface or subsurface and/or groundwater, at a location upgradient of the point of withdrawal, provided: (a) hydraulic containment of the groundwater at the disposal site is maintained so that the Remedial Wastewater discharged upgradient of the point of withdrawal is contained or recaptured within the boundaries of the disposal site;(b) the area of hydraulic containment of the groundwater at the disposal site is monitored at regular intervals of 30 days for the first 12 months following commencement of the discharge, or any modification of the treatment works associated with the discharge, to demonstrate compliance with 310 CMR 40.0045(4)(a), and at regular intervals of three months thereafter for the duration of the discharge, unless additional and/or more frequent monitoring is necessary to demonstrate compliance with 310 CMR 40.0045(4)(a);(c) the discharge is not made to a location at which the concentrations of oil and/or hazardous material in the groundwater at such location is significantly lower than the concentrations of oil and/or hazardous material in the discharge; and(d) the discharge does not exacerbate existing conditions, or prevent or impair the performance of remedial actions, at the disposal site.(5)Requirements for Utility-related Abatement Measures.(a) Any person performing a Utility-related Abatement Measure at a disposal site in accordance with M.G.L. c. 21E and 310 CMR 40.0000 may discharge Remedial Wastewater to the ground surface or subsurface and/or groundwater, provided: 1. the Remedial Wastewater is returned to the ground surface or subsurface at a point within 100 feet of the point of withdrawal;2. the discharge does not exacerbate existing conditions, or prevent or impair the performance of remedial actions, at the disposal site; and(b) Any person performing a Utility-related Abatement Measure pursuant to M.G.L. c. 21E and 310 CMR 40.0000 that includes the discharge of Remedial Wastewater to the ground surface or subsurface and/or groundwater, shall include a description of the discharge, including the concentration of the oils and/or hazardous materials encountered, the pumping rate and volume of the discharge, and a description of any treatment works employed, in the status reports and/or completion reports submitted to the Department pursuant to 310 CMR 40.0465 and 40.0466.(6)Requirements for Discharges Containing Non-Reportable Concentrations of Oil and/or Hazardous Material.(a) Any person performing response actions at a disposal site in accordance with M.G.L. c. 21E and 310 CMR 40.0000 may discharge groundwater containing oil and/or hazardous material in concentrations less than the applicable release notification threshold established by 310 CMR 40.0300 and 40.1600, to the ground subsurface and/or groundwater provided:1. the discharge is not made to a location where the concentrations of any oil and/or hazardous material in discharge exceeds an applicable notification threshold established by 310 CMR 40.0300 and 40.1600 at such a location;2. the discharge is not made to a location at which the concentrations of oil and/or hazardous material in the groundwater at such location are significantly lower than the concentrations of oil and/or hazardous material in the groundwater being discharged; and3. the discharge does not otherwise exacerbate existing conditions, or prevent or impair the performance of remedial actions, at a disposal site.(b) The discharge of groundwater containing hazardous waste at a point outside of the boundaries of the disposal site is prohibited, except as provided by 310 CMR 30.000: Hazardous Waste.(7)Requirements for Discharges That Occur During Well Development or Sampling.(a) Any person performing response actions at a disposal site in accordance with M.G.L. c. 21E and 310 CMR 40.0000 may discharge Remedial Wastewater or groundwater collected during development, purging, or sampling of groundwater monitoring wells to the ground subsurface, provided the Remedial Wastewater or groundwater is discharged as follows: 1. at the point of withdrawal; or2. at a point upgradient of the point of withdrawal if the concentrations of any oil and/or hazardous material in the groundwater at the point of discharge are equal to or greater than the concentrations of the oil and/or hazardous material in the Remedial Wastewater.(b) The discharge of Remedial Wastewater containing hazardous waste at a point outside of the boundaries of the disposal site is prohibited, except as provided by 310 CMR 30.000: Hazardous Waste.Amended by Mass Register Issue 1503, eff. 3/1/2024.Amended by Mass Register Issue S1516, eff. 3/1/2024.