Purpose:

There are almost 4,300 Air Force hazardous waste sites with anticipated cleanup and monitoring requirements that may cost billions of dollars. Environmental sampling for these contaminants is typically performed using long-term monitoring wells installed with auger drill rigs. The expense of installing these monitoring wells and the associated long-term monitoring liability comprise a significant percentage of typical remediation budgets. The use of less costly monitoring wells having wide regulatory acceptance and a valid sampling protocol could result in large cost savings to the Department of Defense (DoD). This project will demonstrate the potential for using direct-push technology (DPT) as a method to significantly reduce the installation and sampling costs associated with long-term monitoring wells.

Description:

The lack of scientific studies comparing the performance of conventionally drilled monitoring wells to those installed using DPT hinders the acceptance of pushed wells for long-term compliance monitoring. During this study, researchers will attempt to validate the use of DPT installed monitoring wells as replacements for conventionally installed wells. To examine the applicability of pushed wells in a variety of geologic regimes and with various contaminants, the following five demonstration sites across the country will be used: Tyndall Air Force Base (AFB), FL; Hanscom AFB, MA; Dover AFB, DE; Naval Construction Battalion Center, CA; and the Cold Regions Research Engineering Laboratory, NH. At all sites, six sampling events will transpire over a 14-month period, and the parameters typically examined for long-term site compliance monitoring will be evaluated (i.e. chemical concentrations, redox potential, pH, inorganic constituents, dissolved oxygen, etc.). A lifecycle cost study will be used to determine the potential cost savings of pushed wells over conventionally installed wells. All of the data, statistical analyses, and lessons learned will be provided to Federal, state, and private organizations to promote the regulatory acceptance of direct-push wells for use in long-term monitoring of groundwater contamination. Upon completion of this effort, a draft update to the American Society for Testing and Materials D 6001, Standard Guide for Direct-Push Sampling for Geoenvironmental Investigations, will be submitted for review and acceptance.

Benefits:

Installation costs of DPT wells are typically much less per linear foot than monitoring wells installed using traditional methods. The drilling-derived liquid and solid wastes increases worker exposure to hazardous substances and significantly increase additional costs for disposal. Contaminated wastewater is created not only during the installation and development of a conventional well, but also during each monitoring event. As remediation activities continue, contaminated groundwater sites will require vast numbers of new monitoring wells both to track migrating plumes and replace old wells that fail for various reasons. Acceptance of this technology for the installation of long-term monitoring wells will result in significant cost savings to DoD and other Federal, state, and private parties with groundwater monitoring needs. (Anticipated Project Completion - 2005)

Contact:

Mr. William Major
Naval Facilities Engineering Service Center
1100 23rd Avenue
Port Hueneme, CA 93043
Telephone: (805) 982-1808
Fax: (805) 982-4304
E-mail: majorwr@nfesc.navy.mil