In order to protect human health, safety, public welfare and the environment, the Massachusetts Department of Environmental Protection (MassDEP) must be notified not more than 72 hours after obtaining knowledge of a release of oil and/or hazardous materials (OHM), which meet the 72-Hour Reportable Condition criteria which are described in the Massachusetts Contingency Plan (MCP; 310 CMR 40.0000).

Some of the most common 72-Hour Reportable Conditions include the following:

  • Nonaqueous phase liquid (OHM that is present in the environment as a separate phase liquid) is identified at a thickness equal to or greater than ½ – inch in a groundwater monitoring well, excavation, or subsurface structure, which is situated more than 30 feet from an occupied residence, school, daycare, or child care center.
  • OHM which is detected in soil or groundwater during an underground storage tank (UST) removal or closure, at concentrations equal to or greater than 100 parts per million by volume, referenced to benzene, using a headspace screening methodology, and the sample was obtained within ten feet of the UST and more than two feet below the ground surface.
  • The detection of OHM in groundwater which is located within the Zone I protection area for a public water supply well (generally within 400 feet) or within 500 feet of a private water supply well, at concentrations equal to or greater than Reportable Concentrations for groundwater category RCGW-1. Groundwater category RCGW-1 has the most stringent groundwater standards since groundwater from these areas are used, or have the potential to be used, as a drinking water source.
  • UST tightness testing results, from either a single wall UST or the inner or outer wall of a double wall UST, which indicate that a leak may be occurring from the UST at a rate equal to or greater than 0.05 gallons per hour.
  • A Condition of Substantial Release Migration exists. The following scenarios are considered a Condition of Substantial Release Migration:
    • Releases of NAPL to surface water, buildings, or underground utilities;
    • Releases of OHM to the ground surface or vadose zone (subsurface soil where groundwater is not present), that is likely to impact groundwater if actions are not taken quickly to contain or remove the OHM;
    • Releases of OHM to groundwater that will migrate, or have the potential to migrate, more than 200 feet per year;
    • Releases of OHM to groundwater that have been detected, or are likely to be detected, within one year in water supply wells, surface water bodies, or a public water supply reservoir;
    • Releases of OHM to groundwater or the vadose zone, that have affected, or have the potential to affect, indoor air quality of a occupied residence, school, daycare or child care center.

The MassDEP must be notified by telephone not more than 72 hours after obtaining knowledge of the 72-Hour Release Condition. The following information must be provided to the MassDEP during the telephone conversation:

  1. The name and telephone number of the caller
  2. Location of the spill
  3. Date and time that the spill occurred
  4. Type of Reportable Condition (i.e. 72-hour)
  5. Type of OHM (i.e. gasoline, chlorinated solvents, etc.)
  6. Source of OHM (i.e. where did the OHM come from?)
  7. Description of the release
  8. Contact information of the owner/operator of the source of OHM
  9. A description of the initial actions taken in response to the release (referred to as Immediate Response Actions in the MCP)
  10. Names of the involved parties (federal, state or local government agencies that have been notified and have responded to the spill)

Following notification by telephone, a Release Notification Form must be submitted to the MassDEP within 60 days. The information required for the Release Notification Form is similar to the information provided to the MassDEP during the initial notification.

If a 72-Hour Reportable Condition exists, actions must be taken immediately to assess, cleanup and/or contain the release. These actions are referred to in the MCP as Immediate Response Actions and are required in the event of a 72-Hour Reporting Condition in order to reduce the risk of harm to health, safety, public welfare and the environment. Immediate Response Actions will be discussed in future blog posts.

If you need more information regarding 72-Hour Reportable Conditions, or if think you may have a Reportable Condition, please contact Omni Environmental Group’s Licensed Site Professionals (LSPs) at 978-256-6766 or