DEEP: Requirement to Report Certain Environmental Hazards

Significant Environmental Hazards

Section 22a-6u of the Connecticut General Statutes (CGS) requires the owner of property which is the source or location of pollution causing a significant environmental hazard to notify the Department of Energy & Environmental Protection (DEEP) after they become aware of such conditions.

A technical environmental professional (TEP) must notify clients and the owner of a property if, while investigating pollution, a determination is made that an environmental hazard is present. A TEP is anyone, including a licensed environmental professional, who collects soil, water, vapor, or air samples to investigate and remediate soil or water pollution as an employee or consultant of a public or private employer. 

In some circumstances, if an owner does not notify DEEP, the TEP's client must report the hazard to DEEP.

Types of Significant Environmental Hazard Conditions:

The significant environmental hazard (SEH) conditions that must be reported to DEEP when identified (because pollution is above threshold concentrations defined in the law) are:

  • Public or private drinking water supply wells with detected pollution (above or below the groundwater protection criteria),
  • Polluted groundwater 500 feet upgradient of or within 200 feet in any direction of a drinking water supply well with pollution detected above the groundwater protection criteria,
  • Polluted groundwater within 15 feet of an occupied building with the potential to pose a short-term risk to indoor air quality,
  • Polluted groundwater discharging to a surface water body with the potential to pose a short-term risk to aquatic life,
  • Polluted soil present within two feet of the surface with the potential to pose a short-term direct contact risk to humans, and
  • The presence of vapors from polluted soil, groundwater or residual free product at levels posing a potential explosion hazard and imminent threat to human health, public safety and the environment.
Consult CGS Section 22a-6u and the notification Guidance and Instructions for further details regarding how the threshold concentrations triggering notification are determined.

Additional Information Regarding Significant Environmental Hazard Condition Notification:

Notification Form and Instructions for Reporting Significant Environmental Hazards
Word Form  / PDF Form / PDF Guidance and Instructions

Reference Tables for Significant Environmental Hazard Condition Notification Threshold Concentrations (Please note: These are general guidelines.  See CGS 22a-6u and the form instructions for further guidance.):

Frequently Asked Questions About the Reporting of Certain Significant Environmental Hazards -Revisions coming soon to reflect July 1, 2015 statutory changes.

Fact Sheet on Reporting of Certain Significant Environmental Hazards - Revisions coming soon to reflect July 1, 2015 statutory changes.

Water Supply Well Receptor Guidance Document

List of Significant Environmental Hazards Reported to DEEP

Relationship of Significant Environmental Hazard Condition Notification Response Activities to Site Remediation Activities:

The Significant Environmental Hazard Statute is intended to identify and abate short-term risks associated with specific environmental conditions identified in the law.  This statute, CGS 22a-6u, does not require that a release be fully remediated in order for a significant environmental hazard to be considered abated.  In some such cases a monitoring program to ensure continued protection of the environment may be required by DEEP. Long-term risks may exist at a release area after short-term risks (significant current exposures) have been abated.  Long-term risks can result from changes in site activities and uses which could change exposures, migration of contaminants over time, long-term exposure to contaminants at concentrations lower than the significant hazard thresholds, and other factors.  Many sites that have submitted notifications of significant environmental hazards may have not completed further remediation activity to achieve compliance with the State Remediation Standard Regulations.

Legislative Summaries for Remediation Programs  Provides information regarding any changes to applicable statutes (see PA 13-308)

Advisory for Short-Term Risks Associated with TCE in Indoor Air

As a result of the increased understanding of the developmental risks posed by volatilization of trichloroethylene (TCE) into indoor air the Connecticut Department of Public Health (DPH) and DEEP developed joint guidance in February 2015.  DEEP recommends including specific evaluation of these risks using the DPH/DEEP guidance when assessing groundwater and soil vapor for potential short-term risks if TCE is present in site groundwater or soil vapor.

For further information, please contact the Remediation Division at (860) 424-3705.

Content Last Updated June 30, 2015