PETROLEUM TERMINAL REMEDIATION
An Engineering Excellence Award-Winning Project

S&ME successfully cleaned up a subsurface petroleum release at a CITGO Petroleum Corporation bulk petroleum terminal in Panama City, Florida by enhancing natural biological processes in the earth. The release, several years ago, from an underground storage tank, allowed a mixture of gasoline and diesel fuel to escape into the subsurface. The mixture contaminated the groundwater and was migrating toward an adjacent bayou.

A treatment system already in place at the site was a protective measure for the bayou but did not address cleaning up the contaminant source, and discharged vapors into the atmosphere. Working closely with CITGO, S&ME recommended going after the source, thus eliminating further contamination of the groundwater and resultant risks.

Our approach enhanced natural biological processes to degrade contaminants to harmless compounds (much like what is done in a common wastewater treatment plant). The process involved a then relatively new technology known as bio venting in which low volumes of air are injected into the subsurface to increase biological activity.

However, a big hurdle to overcome was convincing the state that an air-injection process without simultaneous extraction and discharge of vapors would be a successful solution. S&ME teamed with expert consultants to demonstrate to state regulators that the system would degrade petroleum vapors more quickly than they could be generated. Within six months of Florida's acceptance, the gasoline and diesel fuel contamination had been eliminated from the site. As an S&ME senior geologist put it:

"This is another example of how we seek and find environmental subsurface solutions that can rapidly, efficiently and cost-effectively work without increasing risks of exposure through other media."