Affiliation: | * Yale School of Forestry and Environmental Studies, Greeley Laboratory, 370 Prospect Street, New Haven, CT 06511, USA † Marine Sciences, Texas A&M University at Galveston, Galveston TX 77551, USA ‡ Marine Sciences Institute, University of the Philippines, Diliman, 1101, Quezon City, Philippines § Committee on the Environment and Public Works, U.S. Senate, Washington DC 20510, USA |
Abstract: | Mining operations in Palawan, Philippines, resulted in cinnabar (HgS) mine tailings being used to build a 600 m long peninsula in Honda Bay. Samples collected from the peninsula as well as sediments from the surrounding waters had elevated mercury levels as high as 570 ppm. Natural processes are transporting mercury as much as 10 km from the peninsula, mainly in a coastwise direction, and preferentially associated with fine-grained, organic-rich sediments. Depth of penetration into sediments exceeds 10 cm near the source. As the HgS is transported away from the peninsula, it is rapidly altered to more bioavailable forms; 50% conversion occurs within a distance of only 10–40 m. |