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PROPOSED METHODS TO EVALUATE HYDROPHOBIC ADSORBENTS FOR REMOVAL OF DNAPL IN GROUND WATER

The residual DNAPLs can act as a source of ground water contamination for many years. Standard technologies focus only on methods to aggressively remove residual DNAPLs by either modification of hydraulic gradients, reduction of DNAPL interfacial tension, or both, but have not been successful in complete restoration of DNAPL-contaminated aquifers.

Recognizing the difficulties in restoring DNAPL-impacted aquifers, this paper will propose a feasibility evaluation of an alternative approach to remediation of DNAPL- impacted ground water. Research to test and develop prototype models of the Passive Adsorption Device (PAD), which uses passive in situ adsorption for DNAPL containment and removal, will be described in this paper. Prior technical and limited bench-scale research confirmed the potential for the PAD technology.

Research is proposed to evaluate the feasibility of the PAD technology. Bench-scale studies are proposed to evaluate and quantify prototype adsorbent materials and to evaluate the potential radius of influence of the PAD technology.

Additional tasks are proposed to identify and evaluate the logistics of fabrication of the PADs, and to perform field pilot-scale tests for placement and retrieval of the PAD from ground water monitoring wells and performance evaluations of proto-type designs.

Key words: DNAPL, ground water, passive adsorption device, monitoring wells, prototype design