Connecticut Department of Energy & Environmental Protection

Tiers

Releases must be either closed by submitting a Release Remediation Closure report within one year of the date of discovery of the release OR be assigned to a cleanup tier.

diagram showing relationship between tiers and risk

"Date of Tier Assignment" is the date a release is entered into a tier for the first time. This date remains unchanged throughout the remainder of the release cleanup.

To assign a release to a tier

  • An LEP must complete the tier checklist in the REACT portal (In REACT, select New Submittal from the buttons at the top. In the dropdown under Submittal Category, select Tiers then select Tiers Checklist).  REACT will identify the appropriate tier.
  • Upload the Tiers Characterization report into REACT
  • Pay fee in the REACT portal, unless exempt

Tier reassignment

Releases can be assigned or re-assigned at any time if the risk is reduced

Releases must be assigned to a higher risk tier within 30 days of determining that previously unaccounted for risks to human health or the environment exist

  • Releases assigned to Tier 1A are the highest risk due to unknown risks to receptors or noncompliance that DEEP oversees. 
  • Releases assigned to Tier 1B have known risks to receptors, a remedial action plan is not complete, or ecological risks have not been completed that an LEP oversees.
  • Releases assigned to Tier 2 have controlled risks and no receptor pathways and are overseen by an LEP.
  • Releases assigned to Tier 3 have completed soil cleanup and are completing monitored natural attenuation groundwater monitoring.

Remediation Deadlines

  • Tier 1A -Not more than one year after the date of tier assignment, the release must be closed or assigned to tier 1B, tier 2, or tier 3.
  • Tier 1B - Not more than two years after the date of tier assignment the release must be closed, or assigned to tier 2 or tier 3.
  • Tier 2 - Not more than four years following the date of tier assignment, the release must be closed or assigned to tier 3.
  • Tier 3 - Not more than five years following the date of tier assignment the release must be closed.

Extensions

The commissioner may approve one-year extensions of these deadlines for good cause shown. A request for extension shall be made not less than 30 days prior to the expiration of the deadline and include the fee.

Content last updated February 27, 2026