How significant is atmospheric metal contamination from mining activity adjacent to the Tasmanian Wilderness World Heritage Area? A spatial analysis of metal concentrations using air trajectories models

This study investigatedmetal contamination fromhistoricalmining in lakes in the Tasmanian Wilderness World Heritage Area (TWWHA) and surrounding region. The largest increase in sedimentation and metal contamination occurred ca. 1930 when open-cut mining commenced and new mining technology was introduced into the region. The geochemical signal of lake sediments changed from reflecting the underlying geology and lithology to that reflecting mining activities. The HYSPLIT air particle trajectory model explains metal distribution in the lakes, with those in the northwest region closest to the mines having the highest metal contamination. Lake metal concentrations since mining activities commenced are in the order: Owen Tarn N Basin Lake N Perched Lake N Lake Dove N Lake Dobson N Lake Cygnus,with Perched Lake and Lakes Dove,Dobson and Cygnus in the TWWHA.Metal contamination affected centres up to 130 kmdown-wind of mining sites. Enrichment factors (EF) for Pb, Cu, As and Cd are N1 for all lakes,with Owen Tarn and Basin Lake having very high EFs for Cu and Pb (98 and 91, respectively). Pb, Cu, As and Cd concentrations are above the Australia/New Zealand lower