Pasminco Metals Smelter (PMS) has been in operation from 1987 to 1922. The smelter resumed from 1967 to recently until September 2003 (Morrison, 2003 as cited in Kim et al., 2009). This past operation caused the area to be found with potential heavy metal contaminants such as copper (Cu), zinc (Zn), cadmium (Cd), and lead (Pb). These heavy metals pollution caused the land, air, water to be locally degraded with high level of Pb existing in the soil and resendential areas of the North Lake Macquarie suburbs of Boolaroo, Argenton and Speers Point (Morrison and Gulson, 2007). Waste sewage was distributed into Cockle Creek until the 1970’s when a sludge treatment work was installed (Spurway, 1982 as cited in Olmos and Birch, 2006). Treatments …show more content…
The heavy metal concentrations were in maximum stage in the 1975 sediment than in the 2003 samples, with northern part of Lake Macquarie having much greater metal concentrations than the rest of the other lake (Olmos and Birch, 2006). Aside from historical contamination from the smelter activities, the Lake Macquarie has been found potentital source of lead (Pb) in a form of fine wet-granulated smelter slags (Pasminco-metals, 1993). It has estimated 1.4 million tonnes of slag was stockpiled on the smelter site. These slags deposits underlie many of Norh Macquarie’s parks and playing fields but they were also visible at the surface in many areas (Morrison and Gulson, 2007). A blood Pb survey at 1991 showed that of 129 North Lake Macquarie children in the range of 1 to 4 years old, 84% had blood Pb levels above the current National Health and Medical Research Council (Morrison and Gulson, 2007). However there have been developments by the company to control the emission level but still 37% of 87 children under the age of 5 years tested from July 2001 to June 2002 that had blood Pb levels of 10mg/dL or more (Morrison and Gulson,