General Permit for In Situ Remediation

In situ remediation is the overall term for an accepted suite of technologies that are useful in remediation of polluted sites. In situ remediation treats pollution "in place", below the ground surface and without significant disturbance.  DEEP has developed general permits for the most common in situ remedial activities - enhanced aerobic biodegradation and chemical oxidation.
General permits are issued to authorize similar activities by one or more registrants throughout a prescribed geographic area.  A general permit sets terms and conditions for conducting an activity which, when complied with, are protective of the environment.  Read the general permit carefully to be sure you can comply with the general permit.  If you fail to comply with the general permit, you are potentially subject to legal action.
General permits are a quicker and more cost-effective way to permit specific activities for both DEEP and the permittee.
  • Qualitative or quantitative evidence of pollution is required for any authorization pursuant to a general permit for in-situ remediation.
  • A registration must be submitted to DEEP and may need to be approved for an activity to be authorized pursuant to these general permits.
  • The general permits allow for DEEP issuance of a certificate of coverage in lieu of an approval of registration for authorization of certain activities, and also in some cases, provides for limited self-implementation upon registration.
  • Reporting and recordkeeping requirements for discharge and monitoring activities are specified, and combined reporting is allowed when reporting is also required under DEEP remedial program requirements.
Groundwater monitoring is typically required, especially for potentially affected drinking water supply wells.  The monitoring objective is to document that groundwater quality outside the delineated zone of influence is not affected.  The environmental professional must evaluate monitoring data to determine and report any indications of unexpected outcomes.  Mitigation is required for adverse conditions caused by the discharge.

An easy-to-use two page form has been developed for General Permit reporting.
In Situ Remediation Report of Monitoring Activity Form (the Electronic Transmittal Form must be attached as the cover page)

New Procedure!  Send a copy of the permit registration form and the fee to DEEP, CPPU, 79 Elm St., Hartford, CT 06106-5127.  Upload the Electronic Transmittal Form and the permit registration form to the Connecticut Secure File Transfer (SFT) website.


In Situ Groundwater Remediation: Enhanced Aerobic Biodegradation (DEEP-REM-GP-001)

The General Permit for In Situ Groundwater Remediation: Enhanced Aerobic Biodegradation authorizes oxygenation of groundwater at a controlled rate to enhance in situ aerobic degradation of organic pollutants and allows the use of several different sources of oxygen and delivery methods. Supplemental nutrients or cultured bacteria may also be added under the general permit framework. Chemical oxidation of pollution is not authorized under this general permit; and the permit incorporates limits on ozone and hydrogen peroxide to ensure their use solely as an oxygen source for biodegradation.  Following submittal of all required materials for this general permit, the registrant, in most cases, will be notified in writing if the department will authorize the activity (with or without conditions) or if the registration has been rejected.


In Situ Remediation: Chemical Oxidation (DEEP-REM-GP-002)

The General Permit for In Situ Remediation: Chemical Oxidation authorizes introduction of chemical oxidants and necessary associated substances to soil and groundwater to remediate pollution through the chemical destruction of fuels and other organic materials, and in some cases, chemical modification of inorganic chemicals.  The oxidizing chemical classes authorized are: Peroxides, Permanganates, Ozone, Persulfates, and Percarbonates.

In situ remedial activities not covered by a general permit may still be authorized through the issuance of an individual groundwater discharge permit  or a temporary discharge authorization,  as appropriate for the proposed activity. (Note: if applying for an individual groundwater discharge permit to implement remediation of a site, DEEP recommends contacting DEEP Remediation Division staff prior to the application preparation.)  

Additional Information

In Situ Remediation: Design Considerations and Performance Monitoring Technical Guidance Document  (NJ DEP) – This guidance may be useful for evaluating the potential to use an in-situ remedy. However, any plan developed for in-situ remediation must also consider the RSRs and other applicable Connecticut laws and standards.
Content Last Updated June 9, 2022