The use of microorganisms to bioremediate hydrocarbon-contaminated marine sediments is being investigated as an attractive alternative to the conventional means of environmental restoration efforts in which dredging and disposal of harbor sediments can become cost prohibitive. Where the aerobic biodegradation of hydrocarbons is well established, many of the hydrocarbon-contaminated marine sediments become anoxic within millimeters of the sediment-water interface. Recently, the ability of anaerobic sulfate-reducing bacteria to biodegrade a variety of hydrocarbons including straight and branched alkanes, mono- and alkylaromatic hydrocarbons, as well as polyaromatic hydrocarbons has been well documented. The ability to assess whether in situ remediation of hydrocarbons are occurring in marine sediments is an important aspect in the remedial strategy of natural attenuation. This proposal will deal with the ability to extract pore water from marine sediments and analyze them by GC/MS for the presence of known intermediates of aerobic and anaerobic hydrocarbon decay. The ability to detect signature metabolites of hydrocarbon biodegradation will provide strong evidence for the natural attenuation of these pollutants in marine sediments. Further, the potential commercialization of a screening method and protocol could provide the basis for testing an extensive array of marine and harbor environments around the United States. The ability to rapidly screen and determine whether intrinsic bioremediation is occurring within marine or estuarine sediments goes beyond the interests of just of U.S. Navy. With increased pressure from local and federal authorities on the protection of public waterways and the clean up of polluted environments, the work proposed herein would be applicable to a number of companies involved from shipping to offshore oil drilling operations, in their ability to assess potential bioremediation efforts or the effects of natural attenuation in contaminated marine environments. Surbec-ART Environmental could potentially use the strategies garnered from this proposal to provide a service which would enhance remediation assessments by companies or regulatory agencies in a more timely manner then the traditional laboratory based degradation studies currently used to monitor the bioremediation potential of microorganisms within sediments.
