1. (a) Emergent Reportable Releases Certified as Closed by a Permitted Environmental Professional (1) The remediation of an emergent reportable release shall be determined to have satisfied the requirements of the RBCRs if:

   1. (A) The approximate location and volume of such release was known at the time remediation was commenced;
   2. (B) The substance or substances released are known;
   3. (C) The release:

2. (i) did not occur in or directly to a surface water body and has not migrated to any such surface water body; or(ii) occurred in or directly to a surface water body or migrated to a surface water body, and each substance released is soluble in water or has a specific gravity of less than 1;

   1. (D) The release:

3. (i) has not contacted groundwater; or(ii) consists only of oil or petroleum, is not within 500 feet of a drinking water well, and has not caused a persistent impact to groundwater as determined by subdivision (4) of this subsection;

   1. (E) Remediation commences within the time specified by section 22a-134tt-5 of the RBCRs, and all immediate actions required by section 22a-134tt-5 of the RBCRs are completed in the time specified by that section;
   2. (F) The release is to:

4. (i) Soil, and soil impacted by the release is removed and properly disposed; or(ii) An outdoor or indoor improved surface, and such release is removed to the extent necessary to prevent migration to soil or surface or groundwater, except that if the release is of a material of special concern identified in section 22a-450-6 of the Regulations of Connecticut State Agencies, such release shall be removed until such substance is not detected, which may require removal of the improved surface if such substance is detected in the improved surface; and(G) A PEP who responded to and directed the cleanup of such release certifies, or an LEP who responded to and directed the cleanup of such release verifies, pursuant to section 22a-134tt-11 of the RBCRs, that each of the requirements of this subsection has been satisfied.

   1. (2) For the purposes of determining compliance with subsections (a)(1)(C) and (a)(1)(D) of this section, a release to a secondary containment system designed, installed and operated to collect and contain the release shall not be considered to have occurred in or directly impacted a surface water body or to have contacted or caused a persistent impact to groundwater, provided that:

      1. (A) The volume of the release is less than the volume that the secondary containment system is designed, installed and operated to collect and contain, and the secondary containment system has contained such release; and(B) An assessment of the secondary containment system identifies no damage to such system. Such assessment shall include, but not be limited to, a visual inspection of surfaces coated with epoxy or other coatings. The secondary containment system shall be determined to be damaged if cracks, voids, or gaps in the secondary containment system or in any epoxy or other coating are identified;

   2. (3) For the purposes of determining compliance with subsection (a)(1)(D)(i) of this section, a release shall be determined to have contacted groundwater if:

      1. (A) Groundwater is encountered in the course of excavating or removing the volume of soil necessary to remove soil impacted by the release;
      2. (B) One or more substances released is detected in a properly constructed and developed groundwater monitoring well located immediately downgradient from the approximate location of the release and not more than 5 feet from the edge of the area excavated for the purposes of remediation; or(C) A substance or substances released is determined to be present in the groundwater using any other method or protocol specified by the commissioner by publishing such method or protocol on the department’s internet website.

   3. (4) For the purposes of determining compliance with subsection (a)(1)(D)(ii) of this section, a release of oil or petroleum shall be determined to have caused a persistent impact to groundwater if:

      1. (A) A visible sheen remains on groundwater after not less than 3 attempts within 24 hours at removing the sheen by vacuum extraction of groundwater from an excavation or adjacent monitoring well;
      2. (B) one or more of the substances released is detected in a properly constructed and developed groundwater monitoring well located immediately downgradient from the approximate location of the release and not more than 5 feet from the edge of the area excavated for purposes of remediation 24 or more hours after completion of the excavation of the soil impacted by the release; or(C) A substance or substances released is determined to have caused a persistent impact to groundwater using any other method or protocol specified by the commissioner by publishing such method or protocol on the department’s internet website.
   4. (5) Notwithstanding section 22a-133v-6(e)(7) of the Regulations of Connecticut State Agencies, an LEP may verify that an emergent reportable release has satisfied the requirements of the RBCRs on behalf of his or her employer, provided such verification is consistent with all requirements of this subsection.

5. (b) Releases of Home Heating Fuel on Residential Properties (1) Notwithstanding the requirements of section 22a-134tt-9 of the RBCRs, the remediation of an emergent reportable release or an existing release of home heating fuel pursuant to the standards specified in this subsection shall be determined to have satisfied the requirements of the RBCRs provided:

   1. (A) Applicability (i) the release consists entirely of home heating fuel;

      1. (ii) such heating fuel is being used, or stored for future use on the parcel at which it is being stored, on a parcel with not more than 4 dwelling units; and(iii) such release was created by the owner of the parcel on which the home heating fuel is being used or stored for future use, or by the owner or occupant of a dwelling unit on such parcel. A release shall be determined to have been created by the owner of such a parcel or the owner or occupant of such a dwelling unit if the release would not have occurred but for the actions or inactions of such person or if such person owns, leases, or is otherwise in possession of the equipment that cause the release of home heating fuel;
   2. (B) Cleanup Standard An LEP verifies or a PEP certifies that:

6. (i) all soil impacted by the release has been removed, except that soil impacted by the release may remain if the excavation of such soil may undermine the structural integrity of the dwelling units;

   1. (ii) soil impacted by the release that has not been removed is not impacting groundwater; and(iii) soil impacted by the release that has not been removed is not impacting indoor air;
   2. (C) Documentation A release remediation closure report has been prepared pursuant to section 22a-134tt-12 of the RBCRs that:

7. (i) Identifies the nature and extent of soil impacted by the release that has not been removed;

   1. (ii) Demonstrates that the remediation of the release of home heating fuel resulted in the removal of soil impacted by the release to the maximum extent prudent; and(iii) Indicates groundwater:
   2. (I) was not impacted by the release of home heating fuel; or(II) was impacted by the release of home heating fuel, and an LEP has verified that groundwater has been remediated pursuant to the requirements of section 22a-134tt-10 of the RBCRs.

(Effective March 1, 2026)