Remediation Standard Regulations
An Environmental Program Fact Sheet
What are the RSRs?
Connecticut's Remediation Standard Regulations (RSRs) provide detailed guidance and standards that may be used at any site to determine whether or not remediation of contamination is necessary to protect human health and the environment. The RSRs do not create, in and of themselves, a requirement that remediation be undertaken, nor do they specify a time-frame for completing remediation.
When do the RSRs apply?
Generally, the RSRs apply to any action taken to remediate polluted soil, surface water or a groundwater plume at or emanating from a release area, provided the remedial action is required pursuant to Chapter 445 or 446k of the Connecticut General Statutes (CGS), or Section 22a-208a(c)(2) of the CGS.
The RSRs contain numeric and narrative standards for the remediation of soil and groundwater. The remediation of a polluted property must consider the criteria for both these environmental media. Factors that may effect the degree of remediation at a polluted site include the groundwater quality classification of the site, the land use of the site, and proximity to sensitive receptors of the contamination.
Two remediation criteria must be met when remediating soil. These two criteria are the Direct Exposure Criteria and the Pollutant Mobility Criteria.
Direct Exposure Criteria are established to protect human health from exposure to contaminants in soil. With some exceptions, these criteria apply to soil located within fifteen feet of the ground surface. Polluted soil must be remediated to a concentration that is consistent with the Residential Direct Exposure Criteria, unless the site is used exclusively for industrial or commercial purposes. In such a case, the less stringent Industrial/Commercial Direct Exposure Criteria may be used, provided an Environmental Land Use Restriction is recorded to ensure that the site is not used for residential purposes in the future.
Pollutant Mobility Criteria are established to prevent the pollution of groundwater caused by soil contamination that is available to migrate into groundwater. With some exceptions, these criteria apply to soil located above the seasonal low water table. The Pollutant Mobility Criteria vary depending on the groundwater quality classification of the site. The RSRs also specify when an alternative Pollutant Mobility Criteria is appropriate. The amended RSRs include a compliance option using groundwater quality.
The RSRs also specify circumstances in which the Pollutant Mobility Criteria do not apply. In general, these circumstances include cases where: polluted soil is located beneath a building, provided an Environmental Land Use Restriction is recorded to prohibit the building from being intentionally destroyed; widespread polluted fill exists, provided the groundwater in the subject area is not used for drinking water purposes; or an engineered control, such as an engineered cap, has been constructed to prevent the contamination of underlying groundwater.
The goals of groundwater remediation include:
Preserving high quality groundwater
Protecting existing uses of groundwater
Preventing further degradation of groundwater quality
Preventing degradation of surface water from discharges of contaminated groundwater
Protecting human health
Three criteria apply to the remediation of a groundwater plume. These criteria include Groundwater Protection Criteria, Surface Water Protection Criteria, and Volatilization Criteria.
Groundwater Protection Criteria require that groundwater plumes in high quality groundwater areas be remediated to background quality, or, in certain instances, to levels that adequately protect existing and future uses of groundwater as public or private drinking water supplies. In areas which have been classified as having degraded groundwater quality due to historical land use practices, the groundwater must be remediated to adequately protect any existing use of groundwater. The RSRs also specify circumstances in which exemptions or variances from the Groundwater Protection Criteria are appropriate.
Surface Water Protection Criteria apply to a groundwater plume at the point where the plume discharges to a surface water body. These criteria are established to ensure that surface water quality is not impaired by the discharge of contaminated groundwater into a surface water body at contaminant concentrations above the Water Quality Standards.
Volatilization Criteria are established to protect human health from volatile substances in shallow groundwater that may migrate from groundwater and enter overlying buildings. The Volatilization Criteria for groundwater vary depending on whether the overlying building is used for residential or industrial/commercial purposes. In cases where the industrial/commercial Volatilization Criteria are appropriate, an Environmental Land Use Restriction must be recorded to ensure that the site is not used for residential purposes in the future.
Under specific circumstances, an Environmental Land Use Restriction (ELUR) may be considered as an alternative to remediating contamination to a concentration that is consistent with specific criteria of the RSRs. The purpose of an ELUR is to prevent certain types of uses of a property, to limit specific activities on a contaminated property or to minimize the risk of exposure to the pollutants. For example, an ELUR may prohibit the destruction of a building located above contaminated soil to prevent the contamination from being exposed. An ELUR must be recorded on the municipal land records. The option of using an ELUR is at the discretion of the property owner.
BUREAU OF WATER PROTECTION AND LAND REUSE
DEPARTMENT OF ENERGY & ENVIRONMENTAL PROTECTION
79 ELM STREET
HARTFORD, CT 06106-5127
This overview is designed to answer general questions and provide basic information. You should refer to the appropriate statutes and regulations for the specific language. It is your responsibility to comply with all applicable laws. The information contained in this fact sheet is intended only to acquaint you with the Remediation Standard Regulations. In the event of inconsistencies between this document and the Remediation Standard Regulations, the language in the Remediation Standard Regulations controls.
Content Last Updated September 15, 2017
Connecticut Remediation Standard Regulations | Remediation Programs and Information