Formatted Title
Breaking Benzene: Translating Decades of Anaerobic Bioremediation Research to Field Practice
Background/Objectives
Hydrocarbons are toxic and widespread pollutants owing to releases or spills of petroleum chemicals into the environment. Decades of research has shown that various hydrocarbons including benzene (C6H6), a confirmed carcinogen, can be broken down by both aerobic and anaerobic microorganisms with specialized metabolic capabilities. Benzene-degrading microorganisms are widespread in nature and have the potential to proliferate after a spill event. But as many environmental practitioners will attest, active anaerobic benzene degradation rarely occurs at sites devoid of oxygen. Are anaerobic benzene degraders simply proliferating too slowly to support bioremediation efforts? Are they unable to grow at all? Or are there other factors at play?
Approach/Activities
Results from numerous laboratory treatability studies conducted over the past 7 years has demonstrated enhanced benzene, toluene and o-xylene biodegradation rates with DGG-PlusTM bioaugmentation and provided information to aid in field pilot-test design. Field pilot testing has shown that degradation rates were accelerated in situ through bioaugmentation as observed in corresponding treatability studies. Multiple field applications (in Canada and the US) where bioaugmentation with the DGG-Plus culture occurred are also being monitored.
Results/Lessons Learned
As with chlorinated solvents, bioaugmentation for BTEX compounds has the potential to decrease remediation time frames and increase the range of sites to which bioremediation is applicable providing a much-needed, cost-effective alternative for BTEX remediation in groundwater.
This presentation will summarize data and highlight several field applications (both pilot and full-scale) where these anaerobic cultures. Results to date have shown a range of responses to bioaugmentation including complete degradation of BTEX constituents in several cases. Lessons learned will include identifying the potential for application at complex sites where other co-contaminants are present.