SYMPOSIA PAPER Published: 01 January 1996
STP15583S

Strategy for Developing Remediation Target Concentrations Based on Human Exposure Duration Considerations

Source

A risk-based strategy for calculating remediation target concentrations (RTCs) has been developed based on (1) the toxicity of the substances of primary concern, (2) the exposure period considered when evaluating different types of potential health effects, and (3) the timeframe of potential exposures. In developing RTCs, it is important to consider the likely period of human exposure and the potential for natural attenuation to reduce residual contaminant concentrations over time. Thus, RTCs to be achieved at the completion of active site remediation may be higher than the cleanup goals that must be met, on average, during the period of potential post-remedy exposure.

This methodology for developing RTCs has received acceptance by USEPA for soil cleanup at a Superfund site. For this site, USEPA required that soils be remediated to a level that will protect ground water (i.e., residual soil concentrations that will not result in leachate concentrations that exceed specified ground water cleanup goals) and that ground water contamination be addressed using a pump and treat remedy. An important component of the remedy ultimately adopted at the site is continued monitoring of the ground water to ensure that chemical concentrations in ground water are reduced below the cleanup goals. Soil sampling at the completion of the ground water remedy may also be required to demonstrate that chemical concentrations in soil at the end of the ground water cleanup are also at acceptable levels. Using a leaching model, the soil RTCs were defined as the concentrations remaining in soil after active soil remediation that would not result in leachate concentrations that exceed the ground water cleanup goals, on average, after completion of the ground water remedy.

Author Information

Nielsen, JM
ENVIRON Corporation, Princeton, NJ
Washburn, ST
ENVIRON Corporation, Princeton, NJ
Keoughan, KM
ENVIRON Corporation, Princeton, NJ
Price: $25.00
Contact Sales
Related
Reprints and Permissions
Reprints and copyright permissions can be requested through the
Copyright Clearance Center
Details
Developed by Committee: E47
Pages: 199–215
DOI: 10.1520/STP15583S
ISBN-EB: 978-0-8031-5324-0
ISBN-13: 978-0-8031-1998-7