Hurricane Katrina struck the coastal areas of the northern Gulf of Mexico on August 29, 2005. The tidal surge that accompanied the hurricane ranged in heights of up to 20 feet and extended inland for a distance of up to 20 to 30 miles. The tidal surge extended from the western coast of Mobile Bay in Alabama to New Iberia in the south western coastal area of Louisiana. The tidal surge swept up contaminated sediments from bays, rivers, streams, lakes and marshy areas and deposited the contaminated sediments on all the surfaces contacted by the tidal surge.
The damage was severe and widespread. The silence was deafening. The smell of death frequently slammed into your face. When people will be allowed to return, they will be met with massive destruction or total absence of their homes, businesses and places of work.
The storm's surge-transported sediments were prevalent throughout the area. Sediment layers from six inches to many feet thick coated the surfaces of everything. In some areas the sediment layer had dried and was a powder blowing in the wind when disturbed by the rescue vehicles. In other areas the sediment was still a wet muddy cake. Where the flood waters were still inches to feet deep, the sediment was covered with a water layer coated with an oily rainbow colored sheen.
The sediments originated in the bottoms of water bodies, bays, rivers, streams, lakes, and marshy areas in the path of the hurricane. The water body bottom sediments were contaminated by many decades of discharges and dumping activities from industrial, municipal, business sources and agricultural runoff.
Following the hurricane, more than 80 impacted locations were sampled along the Gulf of Mexico coastal areas from Mobile Bay, Alabama westward to the Vermilion Bay area of southwestern Louisiana. Sediment sludge layers were targeted for sampling in order to determine the contamination levels in the storm surge deposited materials. The sediment sludge samples were analyzed for the parameters listed in Table 1.
Table 1. Analytical Parameters for which the Sediment Sludge Samples Were Tested (available in full paper).
Sediment sludge samples were collected and analyzed from more than 80 locations along the Gulf Coast Hurricane impacted area from Mobile Bay to the southwestern coastal area of Louisiana. The results of the analytical testing performed on the sediment sludge samples are presented in summary form in Tables 2 and 3. The most widespread chemical detected in excess of the Environmental Protection Agency (EPA) and/or state standards was Arsenic.