Section 40.0313 - Releases Which Require Notification within 72 HoursExcept as provided in 310 CMR 40.0317 or 40.0332(7), persons required to notify under 310 CMR 40.0331 shall notify the Department not more than 72 hours after obtaining knowledge that a release of oil and/or hazardous material(s) meets one or more of the following sets of criteria:
(1) a release to the environment indicated by the presence of Nonaqueous Phase Liquid (NAPL) in a groundwater monitoring well, excavation, or subsurface structure in which NAPL has come to be located at a measured thickness equal to or greater than C2 inch (0.04 feet) at any location;(2) a release to the environment indicated by the presence of oil and/or hazardous material within ten feet of the exterior wall of an Underground Storage Tank or within ten feet of ancillary piping, as established by measurement of equal to or greater than 100 parts-per-million (ppm) by volume of total organic vapors "as benzene" in the headspace of a soil or groundwater sample using a headspace screening method, and where such sample was obtained: (a) greater than two feet below the ground surface; and(b) as part of a closure assessment required pursuant to 310 CMR 80.00: Underground Storage Tank Systems and 40 CFR Parts 280 and 281, or in connection with the removal or closure of any underground storage tank otherwise regulated by M.G.L. c. 21O or M.G.L. c. 148;(3) a release to the environment indicated by the measurement of oil and/or hazardous material in the groundwater at concentrations equal to or greater than a Category RCGW-1 Reportable Concentration, as described in 310 CMR 40.0360 through 310 CMR 40.0369 and listed at 310 CMR 40.1600, within: (a) the Zone I of a public water supply well; or(b) 500 feet of a private water supply well;(4) a Condition of Substantial Release Migration, where such condition is associated with a release for which notification otherwise is or has at any time in the past been required in accordance with 310 CMR 40.0300. A Condition of Substantial Release Migration means a condition at a disposal site that includes any of the following:(a) releases that have resulted in the discharge of separate-phase oil and/or separate-phase hazardous material to surface waters, buildings, or underground utilities or conduits;(b) releases to the ground surface or to the vadose zone that, if not promptly removed or contained, are likely to significantly impact the underlying groundwater, or significantly exacerbate an existing condition of groundwater pollution;(c) releases to the groundwater that have migrated or are expected to migrate more than 200 feet per year;(d) releases to the groundwater that have been or are within one year likely to be detected in a public or private water supply well;(e) releases to the groundwater that have been or are within one year likely to be detected in a surface water body, wetland, or public water supply reservoir; or(f) releases to the groundwater or to the vadose zone that have resulted or have the potential to result in the discharge of vapors into a School, Daycare or Child Care Center or occupied Residential Dwelling. Conditions that indicate a potential discharge of vapors into a School, Daycare or Child Care Center or occupied Residential Dwelling include, but are not limited to: 1. soil or soil gas impacted with one or more volatile organic compounds within six feet, measured horizontally from the wall of the structure, and within ten feet measured vertically from the basement floor or foundation at concentrations that are likely to discharge vapors into the structure;2. one or more volatile organic compound in the groundwater exceed the applicable Groundwater Category GW-2 Standard within 30 feet of the structure, and the average annual depth to groundwater in that area is 15 feet or less;3. volatile Light Nonaqueous Phase Liquid (LNAPL) is present in a groundwater monitoring well, excavation, or subsurface depression within 30 feet of the structure at a measured thickness equal to or greater than C inch (0.01 feet); or4. evidence of vapor migration along preferential pathways at a location that is likely to result in the discharge of vapors into the structure.Amended by Mass Register Issue 1503, eff. 3/1/2024.Amended by Mass Register Issue S1516, eff. 3/1/2024.