Remediation Standard Regulations (RSRs) and cleanup standards

Connecticut's soil and groundwater cleanup criteria, set out in the Remediation Standard Regulations (RSRs) and now in the Release-Based Cleanup Regulations (RBCRs) of the Department of Energy and Environmental Protection (DEEP), decide whether a release needs cleanup to protect people and the environment, and when the cleanup is complete. They are rules, not a list of sites.

DEEP words the 2026 change two ways. Its page on the last amendments to the RSRs, last modified February 27, 2026, says they were adopted on February 16, 2021, and that the RBCRs superseded them on March 1, 2026. Its Environmental Cleanup page, with no modified date, says the RBCRs incorporate the RSRs. Its Cleanup Standards page, last modified September 23, 2026, gives the criteria as appendices of the RBCRs.

In a Phase I ESA

ASTM E1527-21 does not name cleanup standards among its standard record sources. They matter when a record says a release was closed: the next questions are which criteria it met and whether the closure rests on a restriction.

• Soil has two criteria. The Direct Exposure Criteria (DEC) protect people from exposure to contaminants in soil and, with some exceptions, apply within fifteen feet of the surface. The Pollutant Mobility Criteria (PMC) keep soil pollution from reaching groundwater; DEEP ties their depth to the seasonal high or low water table, by the area's groundwater classification (GA or GB).
• Residential is the default. Soil within that depth must meet the Residential DEC unless the site is used only for industrial or commercial purposes, residential use is limited to managed multifamily residences that bar residents from digging, or the property is used for passive recreation. Each exception needs a recorded Environmental Use Restriction (EUR), or for passive recreation an EUR or a conservation easement. If a closure used one, look for the EUR or easement; DEEP says EURs are recorded on the municipal land records. See Environmental Use Restrictions.
• Groundwater has three criteria. The Groundwater Protection Criteria (GWPC) call for cleanup to background, or in certain instances to levels that protect drinking water use, in high quality areas, and protection of any existing use where groundwater is classified as degraded. The Surface Water Protection Criteria (SWPC) apply where a plume discharges to surface water. The Volatilization Criteria (VC) guard against vapors entering buildings above a plume, and vary with whether the building is in residential or industrial or commercial use.
• A closure can rest on an exception. DEEP's compliance measures page, last modified April 13, 2026, lists variances, alternative criteria and conditional exemptions, several tied to the commissioner's approval, an EUR or a permit by rule. An exemption from the VC through vapor mitigation in an existing building, for example, takes the commissioner's approval and an EUR. Ask whether a closure relied on one, and for the approval or restriction it names.
• Tank releases use them too. DEEP says underground tank releases required to be cleaned up under 22a-449(d) fall outside the RBCRs' discovery provisions, but that the cleanup standards set their endpoints. See UST Clean-Up.
• The date matters. DEEP gives March 1, 2026 as the RBCRs' effective date, so a closure dated earlier was made under the rules then in force. The general reading is on Old closure and today's cleanup criteria.

How a site closes

Under the RBCRs, DEEP says a release must be closed with a Release Remediation Closure report within one year of discovery or be assigned to a cleanup tier (see the Release-Based Cleanup Program page). A Licensed Environmental Professional (LEP) may verify that an endpoint has been reached for any release or site. Under the legacy Voluntary Remedial Program 133y, which DEEP dates June 29, 1995 to March 1, 2026, completion took an LEP's signed and sealed Verification Form and Final Remedial Action Report. Ask for the verification or closure report and any EUR it relies on; DEEP advises searching the municipal land records to confirm an EUR is recorded and in force.

Where to read the rule and the numbers

• DEEP's Cleanup Standards page links each criterion to its appendix of the Release-Based Cleanup Regulations and lists technical support documents, among them a derivation of the 1996 RSR criteria. They were not opened for this handbook, so no value is stated here.
• The RBCR Compliance Measures page gives the exceptions with sections of the regulations and links the Alternative Groundwater Protection Criteria Map.
• DEEP's Emergency Response and Spill Prevention page links the Remediation Standard Regulations.
• Questions about the RBCRs go to DEEP.RemediationDivision@ct.gov.

Where to look a site up

DEEP says to search REACT for releases and cleanup progress, and keeps a map of Environmental Use Restrictions.

Getting the file

Documents are in REACT, the DEEP Online Document Search Portal or the Environmental Quality Records Center, by program and date; the overview gives the routes and cut-off dates.

Sources

Department of Energy and Environmental Protection pages, read October 17, 2026:

• Cleanup Standards, last modified September 23, 2026.
• RBCR Compliance Measures, last modified April 13, 2026.
• Licensed Environmental Professional and Permitted Environmental Professional Roles, last modified April 13, 2026.
• Wave 2 Revisions to the Remediation Standard Regulations and Environmental Use Restriction Regulations - Concepts and History, last modified February 27, 2026.

Department of Energy and Environmental Protection pages, read October 8, 2026:

• Release-Based Cleanup Program, last modified August 25, 2026.
• Tiers, last modified May 6, 2026.
• Voluntary Remediation Programs, last modified April 13, 2026.
• Environmental Use Restrictions, last modified March 26, 2026.
• Environmental Cleanup, no modified date shown.
• Remediation Division Files, last modified March 18, 2026.
• Emergency Response and Spill Prevention, last modified July 2026.