Acid Sulfate Soils (ASS) are a naturally occurring soil type found throughout the world along the coastal plains. When these soils are disturbed and exposed to air, oxidation occurs and when mixed with water sulphuric acid is produced.

For every one tonne of sulfidic material that completely oxidises, approximately 1.6 tonnes of sulphuric acid can be produced, dependant upon the amount of oxidisable sulphur present. This acid will reduce soil productivity, may require expensive lime to be added, and can drain into waterways to cause short and long term social, economic and environmental impacts. This acid can dissolve the concrete from around bridges, or within pipes, and can leach and concentrate elements, such as aluminium, from the soil to toxic levels.

Guidance for construction activities

The purpose of the below document is to provide guidance when undertaking ground works within the Richmond Valley Council area and to allow for proper management of Acid Sulfate Soils. The document provides step-by-step instructions for managing ASS in relation to undertaking ground works and includes the appropriate reference points for specific steps in the process.

For more information phone Council on (02) 6660 0300.