A contemporary contamination record of stormdrain and harbour sediments, Wellington, New Zealand

 Sediments from stormdrain catchments and outlets in Wellington city and sediment traps from Wellington Harbour were sampled for trace metal content. Samples were analysed for total metal content using XRF and ICP-MS. High values of Pb and Zn were found in stormdrain catchments and outlets, decreasing to elevated background rock levels in the harbour. Maximum values were recorded in an inner city stormdrain catchment, with levels of Pb (4605 ppm), Cu (2981 ppm) and Zn (3572 ppm) all higher than the biological probable effects levels (PEL). Concentrations of As, Cr, Cu, Pb, Ni and Zn concentrations in all harbour sediment trap samples were below the PEL. The mean values for each harbour sediment trap sample can be used as an accurate historical baseline in future studies. Stormdrain samples with high trace metal levels were close to industrial and construction sites. The proximity of these outlets to recreational areas should be of concern to local authorities. Received: 28 August 1997 · Accepted: 15 December 1997     

Acid leached analyses of stormdrain and harbor sediments, New Zealand

 Sediments from stormdrain catchments in Wellington city and sediment traps from Wellington Harbor were sampled for trace metal content. Samples were analyzed for acid leached metal content by extraction with 0.11 mol acetic acid l^–1 and using ICP-MS. Cu and Zn levels in harbor sediment traps increased towards the periphery of the harbor, while Pb levels adjacent to a road almost doubled. In general, areas of light industry in the Inner City stormdrain catchments exhibited higher acid leached metal concentrations. However, large-scale renovation work probably contributed to point sources of high metal levels. The proximity of stormdrain outlets to recreational activities, such as wharf fishing and shellfish gathering, should be of prime concern to local authorities. Some positive correlations are found between acid leached and total metal levels. These may prove useful for assessing the biological impact of significant increases in total metal concentrations in the vicinity of Wellington Harbor. Significant savings in the time and costs of analyses may be achieved. Received: 27 February 1998 · Accepted: 27 April 1998