INFLUENCES ON THE EXTENT AND RECORD OF HEAVY-METAL POLLUTION IN SEDIMENT CORES FROM LOCH-TAY IN A MINERALIZED AREA OF SCOTLAND

The distribution and inventories of Pb in the sediments of Loch Tay ha ve been strongly influenced by inputs from past Pb mining activity, as demonstrated by correlation with the characteristic (206)pb/Pb-207 si gnature of the Tyndrum ore deposit. A major depositional event, perhap s associated with the cessation of Pb mining in the area, has been dat ed at 1906-1928 by the Pb-210 method. Zinc and Cu have been influenced to a lesser extent by mining, as shown by comparison with inventories in Loch Lomond. Profiles of As, Mn and Fe have been affected by post- depositional diagenetic remobilisation processes. The results serve as a benchmark, with Au mining set to commence at Cononish, near Tyndrum , in 1996.