1980’s: Lake Goolellal (WA). Pesticides: Chlordane

Organochlorine Residues in Sediments and Soils in and around Lake Goolellal (Gerritse 1988 in EPA Bulletin 354)

Lake Goolellal is one of a number of natural wetlands in the coastal plain, situated amongst the northern suburbs of metropolitan Perth. It has been treated with organochlorine insecticides on a number of occasions for Argentine Ants.

The study involved the analysis of samples of soil, sediments and lake water taken from six points along each of two transects into the Lake, starting from the road (Lakeway Drive). Levels of all organochlorins peaked about 50m from the shore line, and were found within 4 cm of the soil surface. No dieldrin or heptachlor was detected in the sediments of the lake.

Based on information on the use of these chemicals for Argentine Ant control, their half-lives in this situation were tentatively estimated to be much less than one year for heptachlor and chlordane – considerably less than is reported in the literature.

P55 Monitoring Pesticides – A Review – A Report to the Environmental Protection Authority by Peter A Rutherford. Environment Protection Authority. Perth Western Australia. Bulletin 407. December 1989.