Acid Sulphate Soil

When seawater inundated the land thousands of years ago, the sulfates in sea water reacted with iron oxides in the soil. Under anaerobic conditions, bacteria in soils reduced these sulfate ions from the sea water and produced hydrogen sulphides. This in turn reacted with the iron in the soils to produce iron oxides (FeS2).

When Acid Sulfate Soils can be detrimental to the environment when exposed to atmospheric air through anthropogenic activities (excavation for construction purposes etc) or natural means (drainage of groundwater).

Environmental consequences from Acid Sulfate Soils include:

1. Decrease in pH of soils leading to acidic nature and subsequent release of metals such as iron, aluminium and arsenic into the groundwater and surface water
2. Fish kills and diseases in fishes due to iron precipitation leading to damages to fish population and causing environmental non-compliance
3. Damages to assets through the corrosion of steel products in structures
4. Additional financial liability for treatment of the acidic soils and potential fines

At K2E we assist our clients manage their Acid Sulfate Soils in an efficient way by offering the following services:

1. Desktop review of the sites such as review of state maps and other publications for the presence of Potential Acid Sulfate Soils (PASS)
2. Development of Conceptual Site Model to develop an investigation strategy
3. Preliminary intrusive investigation involving drilling, sampling, field testing and laboratory analysis of soils
4. If soils are determined to be Acid Sulfate Soils (ASS), then suitable treatment strategy is developed in the form of Acid Sulfate Soils Management Plan
5. Monitoring of neutralisation activities and validation reporting
6. Liaison with authorities

If unnoticed, Acid sulfate soils are usually dormant and does not indicate the contamination (typical colouration of soils from iron deposits) until excavation has occurred, but it is too late by then. If you suspect that your project can be affected by Acid Sulfate Soils, feel free to contact us to discuss about your scenario.

We maintain the confidentiality of our clients and their site related issues.