Objective

The Tri-Service and EPA test locations of the SERDP National Environmental Technology Test Site (NETTS) program were comprised of a network of well-characterized demonstration sites at Department of Defense (DoD) installations. The goal of this SERDP-funded program was to provide accessible, well-supported field locations for project proof-of-principle tests, applied research, and comparative demonstrations, as well as to facilitate transfer of innovative environmental technologies from research to full-scale use. The SERDP NETTS program was created primarily for DoD, Department of Energy (DOE), and Environmental Protection Agency (EPA) users, but the locations also were available to other agencies and the private sector.

The former McClellan Air Force Base (AFB), located near Sacramento, CA, closed as an active Air Force installation in July 2001.  In addition to other DoD depot installations undergoing Base Realignment and Closure (BRAC), the Air Force was pursuing the privatization of McClellan AFB to prepare for its closure. However, due to extensive contamination resulting from base activities, the site cleanup is estimated to continue into the next century and result in a cost of more than $1 billion.  The primary focus of the McClellan AFB NETTS was to provide a well-characterized facility for the research and demonstration of technologies that pursue the detection, monitoring, and cleanup of chlorinated hydrocarbons, fuels, and metals in both the vadose zone and groundwater.

Bioreactor installed on demonstration test pad at the base’s Groundwater Treatment Plant. All utilities and service connections are provided by the Test Site

Technical Approach

The majority of the base was available for demonstrations conducted under NETTS.  While it hosted the NETTS program, McClellan AFB had an active, large cleanup program with eight operational Soil Vapor Extraction (SVE) systems. All systems had dedicated utilities that allowed slipstream demonstrations. The McClellan AFB groundwater treatment plant serviced 23 extraction wells. In addition, there were five groundwater treatment systems with 13 extraction wells. The SVE systems and groundwater treatment facilities provided opportunities for demonstrating in situ and ex situ techniques for remediating soils and groundwater contaminated with solvents. Both the McClellan AFB NETTS and McClellan AFB cleanup programs were focused on developing and utilizing environmental technologies that had a potential to shorten cleanup schedules and reduce costs. This relationship resulted in significant sharing of funds, data, and other resources.

Results

McClellan AFB provided a technical niche to investigate technologies for the treatment of extracted soil-gas contaminated with chlorinated solvents and other hydrocarbons; unsaturated soils contaminated with chlorinated solvents, heavy metals, as well as semi-volatile and nonvolatile organic compounds; and ex situ treatment of groundwater contaminated with chlorinated solvents. The below table provides a list of some of the demonstrations which were hosted at McClellan AFB. 

TITLEPERFORMER
Use of Cometabolic Air Sparging to Remediate Chloroethene-Contaminated GroundwaterAir Force
Vadose Zone Monitoring System for Volatile Organic Compounds (VOCs) in SoilsDOE-LBNL
Ex-Situ Fluidized Bed Bioreactor for Treatment of VOCs in GroundwaterEnvirogen, Inc.
Ex Situ Fluidized Bed Cometabolic Bioreactor for Treatment of Chlorinated Aliphatic Hydrocarbons in GroundwaterEFX Systems
Passive Diffusion Membrane SamplingTRW
Innovative Sensors for Measuring VOCs in GroundwaterGeneral Atomics

Benefits

The NETTS program established test locations at federal facilities for hosting government and private organizations to rigorously test and evaluate new environmental characterization and remediation technologies. The demonstration program at each location was designed to obtain realistic environmental and economic information that may transfer nationwide to support the adoption and use of more cost-effective and high-performance technologies. (Completed – 2001)