Some housing and other developments open up ground (former sea beds) that when exposed to the oxygen in the air and combined with ground water or rain, starts producing large quantities of acidic water. Typically known as acid sulphate, it’s caused by pyrites in the soil oxidising to sulfuric acid.
Developments and dredging may require the excavation of acid sulphate soils that when exposed to oxygen, produce acidic runoff. Acid sulphate soils are common in low lying areas (typically <5m AHD).
Excavations in these areas therefore need to be assessed prior to commencement of work to determine the acid generation potential of the soils or sediments to be disturbed.
Simmonds & Bristow has the capability to conduct acid sulphate soils investigations in accordance with standard Queensland Guidelines.
An Acid Sulphate Investigation involves adequately characterising the material being excavated using recognised soil sampling and field measurement techniques, to measure the acid generation potential (in our laboratory), to determine the liming requirements to neutralise any acid generation, and to prepare an acid sulphate soil management plan that clearly states the procedures for managing the risks of adverse environmental impacts.
Simmonds & Bristow holds NATA Accreditation for soil sampling and Acid Sulphate Soil Analysis.
The results of laboratory analysis are used to determine the management plan (including liming requirements for both soil and dewatering). The laboratory testing plan is designed on the basis of information gathered during the site visit, including site descriptions and in-situ pH measurements.
Simmonds & Bristow is currently providing support consulting services to Rural Solutions SA, who are working on the remediation of an acid sulphate affected water body near Goolwa, South Australia. Rural Solutions SA is part of the team undertaking in-situ limestone trials as part of the Emergency Management Response undertaken by the South Australian Government.
Simmonds & Bristow is currently undertaking an experimental limestone dosing trial using six (6) different types of material. This information will be used to fine tune management actions on site, such as installation of limestone mounds, limestone barriers and aerial application.