Recirculation Bioreactor Demonstration at Landfill 3, Altus AFB, Oklahoma
Douglas C. Downey, John R. Hicks, Jason B. Bidgood, Chuck Butchee
A pilot-scale field demonstration of a recirculation bioreactor was performed at Altus Air Force Base, Oklahoma, Landfill 3. Groundwater contaminated with chlorinated aliphatic hydrocarbons (CAHs) was recirculated between a 30-foot by 30-foot, mulch-filled, in situ bioreactor test cell and a downgradient extraction trench. Recirculation was accomplished using a solar-powered pump. The purpose of constructing and operating the bioreactor was to demonstrate the degree to which a combination of organic material addition and accelerated leaching can reduce source area concentrations of CAHs in unlined, closed landfills and other CAH-contaminated sites. During five performance monitoring events performed over a 2-year operation period, the bioreactor removal efficiencies for trichloroethene (TCE) and total chlorinated ethenes (sum of TCE, dichloroethene, and vinyl chloride) from recirculated groundwater ranged from 97 to 100 percent and 76 to 96 percent, respectively. Over the two-year operation period the toxicity of groundwater between the bioreactor and the extraction trench was reduced by 90 to 95 percent. A recirculation bioreactor is expected to be a cost-effective, full-scale remediation technology. Costs associated with full-scale recirculation bioreactor installation and operation are estimated to be similar to, but slightly less than, source area treatment with organic substrate injection, and considerably less than a RCRA cap with leachate collection and treatment.
In summer/fall 2006, the bioreactor will be recharged with vegetable oil and bioaugmented with a microbial culture bred to facilitate complete reductive dechlorination of TCE to non-toxic end products; the impact of these enhancements on groundwater quality will be presented.
Douglas C. Downey
Parsons, 1700 Broadway, Suite 900, Denver, CO 80290, USA, firstname.lastname@example.org, Telephone: (303) 764-1915, Fax: (303) 831-8208
John R. Hicks
Parsons, 1700 Broadway, Suite 900, Denver, CO 80290, USA, email@example.com, Telephone: (303) 764-1941, Fax: (303) 831-8208
Jason B. Bidgood
Parsons, 1700 Broadway, Suite 900, Denver, CO 80290, USA, firstname.lastname@example.org, Telephone: (303) 764-8836, Fax: (303) 831-8208
97 CES/CEV, 401 L Ave., Altus AFB, OK 73523, USA, email@example.com, Telephone: (580) 481-5187, Fax: (580) 481-5841
Presenting Author: Jason Bidgood