University of South Florida
Panhandle beaches show signs of improvement[03.02.2011]
TAMPA, Fla. -- Many beaches in Florida’s Panhandle and in parts of Alabama hit hard by the Deepwater Horizon oil spill appear to have been thoroughly cleared of visible tar balls and layers of buried oil beneath the sand, but residual oil contamination can still be detected under UV lights, according to a new report from USF’s Coastal Research Lab.
In his most recent survey of the area’s beaches for a National Science Foundation project, USF Geologist Ping Wang found little to no visible tar balls on the surface, below the sand or in the swash zone -- where waves wash up onto the beach and typically deposit seaweed and debris -- in areas surveyed from Panama City Beach west to Dauphin Island, Ala.
In a three-day field investigation from Feb. 19-21, the researchers said any residual oil stain on the beaches only could be identified by ultraviolent light. There is little to no visible oil, nor have the famed sugary-white sands been stained oily brown, according to the report authored by Wang and researchers Rip Kirby and Jun Cheng.
That’s good news with spring break vacations right around the corner, and a relief to some tourist towns who had feared the damage from the spill disaster would be irreversible, said Wang, who is an associate professor in the Department of Geology.
USF researchers were among the first scientists to begin documenting the spill’s impact on the beaches through the NSF’s Rapid Response Grant. In addition to the thick sheets of oil that contaminated the beaches after the April 20 rupture of the Macondo well, USF researchers documented thick layers of oil buried inches beneath the sand by wave action and then later found that beaches that had been “cleaned” by BP remained contaminated when oil sheets were chopped into tiny tar balls.
Their work -- documented by National Geographic -- highlighted the need for more thorough cleanups. Again in August, the researchers still found oil contaminated the beach areas.
Since then, cleanup crews have subjected the beaches to “aggressive” mechanical cleanup which local residents came to call “dig-sift-refill”, Kirby and Wang said. A separate USF study headed by Professor Susan Bell, chair of the Department of Integrative Biology, and funded by the NSF is examining the spill’s effect on the small creatures whose habitats include the beach and the swash zone and who might have been affected by the cleanup.
“We found that most of the small surface residual tar balls on the beach were removed or further pulverized to sizes that cannot be identified with untrained eyes. The beaches appear to be in similar condition as before the spill, except the massive temporary tire/tilling tracks,” the researchers’ report stated.
The researchers paid particular note to tar ball distribution in the swash zone near the shoreline, and area where many beach visitors, particularly young children, tend to play. The scientists had been concerned that since weathered tar balls with sand grains were heavier than sea water, tar balls may concentrate in the swash zone and impose some risk to swimmers.
But very few small tar balls were found in the swash zone along the Alabama and Florida panhandle beaches. The study, however, did not include looking for tar mats several inches thick reported to be submerged offshore, Wang noted.
Wang credits the relatively calm 2010 summer and winter weather, which allowed the buried oil to mostly remain buried in place instead of being eroded and then redistributed by waves over a larger area to be helpful to the beach cleanup efforts. This effectively provided time for the cleanup effort to remove or pulverize the rather “static” surface and buried oil on the beach.
Read the full report by Wang.
Filed under:Arts and Sciences Geology School of Natural Sciences and Mathematics Research CreditsAuthor: Vickie Chachere Contact: