Robert Turpin, director of Escambia County’s Marine Resources Division, descends alongside the Oriskany.

How much PCB contaminant will scrapped Navy vessels add to the undersea environment? Two University of West Florida scientists, under a $315,000 contract from the Department of Navy Funding, hope to find out.

Two days ahead of the May 17 sinking of former aircraft carrier Oriskany, biologists Dick Snyder and Will Patterson completed gathering of 105 samples from fish tissue, water particles and sediment near the vessel's designated resting site in the Gulf of Mexico, to analyze for PCB content.

PCBs -- polychlorinated biphenyls, once-common industrial materials -- were outlawed in 1977.

The Oriskany, cleansed of liquid PCBs prior to sinking, still has solid PCB-containing materials on board. Subsequent sampling of Oriskany environs will be needed to assess the vessel's impact on the offshore eco-system.