Bulletin Board Magazine 2018 Volume 3

Legal/Legislative Continued

the context of development and redevelopment sites are volatile organic compounds or "VOCs". As the name implies, VOCs are volatile in nature and are highly mobile in groundwater. They are also ubiquitous and are a common groundwater contaminant related to numerous sources including fossil fuels, benzene, paints and coatings, MTB and perchloroethylene commonly used in the dry cleaning industry. These combination of factors make addressing VOCs a common problem in the context of remediation of groundwater and indoor air. DEP released Guidance in August 2018 that will in certain cases facilitate voe ground water remediation efforts.

Previously, capping was not allowed by DEP as a remedial option for the prevention of contaminants from impacting groundwater at sites where an exceedance of DEP impact to groundwater soil screening level or impact to groundwater soil remediation standard had been detected. This was due to the potential for such contaminates to migrate downward to impact groundwater via infiltration or through vapor gas processes. DEP's recent guidance now confirms that capping may be used as a remedy to address such exceedances at sites where vadose zone soils are contaminated with voes and groundwater contamination has not occurred, and at sites where groundwater contamination is confirmed.

Conditions include a requirement that all free product be removed to extent practicable, a CEA for groundwater must be established with a defined time limit as opposed to a CEA established in perpetuity, a low permeability cap must be installed to minimize precipitation infiltration and a monitored attenuation remedy must be implemented. It is anticipated that this guidance change will help to facilitate more cost effective groundwater remedies in connection with development and redevelopment activities.

Bulletin Board | 35 | www.shorebuilders.org

Bulletin Board | 36 | www.shorebuilders.org