0011-9164/09/$– See front matter © 2008 Elsevier B.V. All rights reserved. Desalination 244 (2009) 261–282 Levels of heavy metals in subtidal sediments in the vicinity of thermal power/desalination plants: a case study S.A. Abdul-Wahab a* , B.P. Jupp b a Mechanical and Industrial Engineering Department, Sultan Qaboos University, PO Box 33, Al Khoud, PC 123, Muscat, Sultanate of Oman Tel. +968 (24) 141360; Fax +968 (24) 141316; email: sabah1@squ.edu.om b Marine Pollution Monitoring Section, Ministry of Environment and Climate Affairs (MECA), PO Box 175, Mina Al Fahal, PC 116, Muscat, Sultanate of Oman Received 22 February 2008; Accepted 8 June 2008 Abstract Sediments can accumulate various pollutants and are widely used for environmental monitoring of human impact. The central purpose of this study was to examine the levels of eight heavy metals in subtidal sediments in the vicinity of two thermal power/desalination plants in Oman: (1) the Barka power/desalination plant and (2) the Al-Ghubrah power/desalination plant. The samples of bottom sediment were collected with a grab sampler. The samples were analysed for cadmium (Cd), chromium (Cr), copper (Cu), iron (Fe), nickel (Ni), lead (Pb), vanadium (V) and zinc (Zn). Sediment samples were collected at different stations. Some of these stations were located near the intake of the two plants, others were located at different distances and directions from the vicinity of the outfalls (outlets of the discharge). In addition to heavy metal analysis, other physical and chemical parameters measured simultaneously in the water include temperature, salinity, conductivity, and dissolved oxygen. The results indicated that the sediments were not polluted by heavy metals. The levels of Cu, Zn, Pb and Cd in sediment appear to be derived from the discharge whereas the levels of the other metals (Cr, Fe, Ni,V) appear to have a geochemical source. Keywords: Power/desalination plants; Discharge; Sediment; Heavy metals; Oman 1. Introduction Human activities may greatly increase heavy metal concentrations in coastal sediments [1,2]. The contamination of sediments with heavy *Corresponding author. metals may lead to serious environmental prob- lems and in some cases action has to be taken place for their decontamination [2]. Recent rapid increases in coastal developments in the Sultanate of Oman include large ports with industries (Sohar, Salalah), large power/desalination plants doi:10.1016/j.desal.200 .0 .0 8 6 07