Engineers Australia

Acid sulphate soils and rocks – occurrence and management in the Illawarra Region

Bob Batchelder

Abstract

This paper briefly defines Acid Sulphate Soils (ASS), their formation, their propensity to form sulphuric acid on exposure, the occurrence of ASS in the Illawarra Region (mapping, typical environment), ASS identification / investigation, laboratory testing techniques, statutory requirements, management techniques, Acid Based Accounting (ABA) and monitoring. The paper also refers to three case studies, one in the Illawarra, and two just south of the Illawarra region, including: ASS affected development sites near Bulli / Nowra and a Potentially Acid Forming (PAF) bedrock site on the Princes Highway deviation and upgrade at Conjola Mountain NSW.