Objective:

The objective of this project is to develop a protocol and a screening tool that allows for the rational selection, design, and performance estimation of technologies that treat source-zone dense non-aqueous phase liquids (DNAPL) in groundwater. Once developed, the user-friendly screening tool can be used to reduce the uncertainty of estimating and predicting remedial outcomes.

Technology Description:

Key to developing the screening tool is the use of modeling to generate realizations of DNAPL treatment based on the interaction of fundamental factors. The data from these realizations will be used to generate simpler relationships that can be programmed into the screening tool and verified by comparison to field data from ongoing and competed DNAPL remediation projects or demonstrations. The project will be executed as follows: (1) review data from a recent Navy survey; (2) assess developments of several ongoing SERDP and ESTCP projects; (3) incorporate the Interstate Technology and Regulatory Council's (ITRC) information base; (4) incorporate the Environmental Protection Agency's (EPA) Technology Innovative Office (TIO) guidance; (5) create a three-dimensional matrix based on factors related to DNAPL behavior, hydrogeology, and technology capability and limitations; (6) use numerical modeling to simulate DNAPL distribution and remediation in the subsurface; (7) validate the screening tool at two sites; and (8) develop a user manual (i.e., protocol) for the screening tool to provide a decision framework for selecting remediation and performance objectives. These objectives will be consistent with what is technically achievable given a site's geology and DNAPL distribution as well as a technology's treatment capabilities. The challenge will be to integrate the models and theory to create an understanding of what is achievable or what needs to be achieved to make source remediation a worthwhile endeavor. By using templates and multiple releases along with sensitivity analysis, factors affecting the success or failure of any source zone remediation can be defined.

Expected Benefits:

In a cost metrics comparison of treatment technologies for chlorinated hydrocarbons, pump-and-treat was estimated at $9.8 million per site, permeable reactive barriers (PRB) at $3.9 million per site, and accelerated source treatment at $1.3 million per site. The Department of Defense (DoD) owns close to 3,000 sites contaminated with chlorinated hydrocarbons. Although it's uncertain how many contain a source area, it is apparent that at least 10% of these sites still contain chlorinated hydrocarbon concentrations in excess of 1% aqueous solubility (defined by EPA as a source zone). If 300 of these sites could benefit from this approach, application of the protocol would be significant in the selection of a remedial approach. If cheaper technologies are selected as a result, DoD potentially could save between $702 million (over PRBs) and $2.295 billion (over pump-and-treat). (Anticipated Project Completion - 2009)

Principal Investigator:

Ms. Carmen Lebrón
Naval Facilities Engineering Service Center
Restoration Development Branch
1100 23rd Avenue, ESC-411
Port Hueneme, CA 93043-4370
Telephone: (805) 982-1616
Fax: (805) 982-4304
E-mail: carmen.lebron@navy.mil