research program 3
environmental applications of regolith geoscience
Avon Catchment Council - Acid Groundwater (AG3)
Project Leaders : Paul Shand, CSIRO Land and Water and Brad Degans, WA Dept Environment and Water
Start date and duration: 01.07.06-30.06.09
Participants : Consortium of LEME, Dept of Environment WA, Dept of Water WA, Department of Agriculture WA – WA Engineering Evaluation Initiative and Avon Catchment Council
Brief project description :
This new project forms part of the Avon catchment Council (ACC) investment in Salinity Management. The project will be managed by the WA Department of Water. The project will build on the outcomes of the two current P3 acid drainage geochemistry risk assessment projects (3.15 and 3.23). Both these projects have established that acid drainage waters in the WA wheatbelt are widespread and contain highly elevated levels of heavy metals and trace elements. The two projects have also established appropriate sampling protocols, water and sediment analytical procedures (in the presence of highly elevated salt concentrations) and made some initial management recommendations. However, if drainage is to be widely adopted as a salinity mitigation management tool in areas of acid groundwater then appropriate technical options for the treatment of acidity and mitigation of trace elements need to be developed.
Treatment technologies for acidity and trace element mitigation will be trialled and demonstrated in three ways:
• Through the construction and study of pilot scale engineered treatment/evaporation basins where a range of treatment options will be trialled;
• Investigating the feasibility of ‘in-drain' treatments that do not require significant engineering works; and
• Amelioration of acidity and associated trace element precipitation through mixing acid drainage waters with alkaline surface waters
Project aims
• to review and report on available treatment methods for acidic drainage waters
• to identify feasible treatment methodologies and identify sites for method evaluation;
• construct and evaluate practical options for treatment of acidic saline drainage waters, focussing on the discharge point of drains;
• evaluate simple, low cost options for treatment of acidic saline drainage waters in drains;
• identify, evaluate and demonstrate practical options for treatment of acidic saline drainage waters exploiting mixing with alkaline surface waters;
• develop a set of best-management practice guidelines for such drainage treatments in the Avon catchment;
• promote the outcomes of evaluation trials and best management guidelines to the broader community in the Avon River Basin ;
• contribute to 2006-2008 investment planning for salinity management in the Avon Region.
Deliverables (outputs) and expected impacts of research (outcomes):
Outputs
- Acidity and geochemical changes- the proportion of metals in solution compared to the proportion of metals precipitating out into sediment material will be monitored throughout the study using advanced analytical techniques (Inductively Coupled Plasma-Mass Spectroscopy, X-ray diffraction, isotope analysis
- Geochemical models will be developed to predict the behaviour of trace elements and heavy metals during treatment feasibility studies
- Information on the feasibility of treatment and disposal options will be communicated to end-users through; pilot scale demonstration trial field days.
- Incorporation of management recommendations into EEI, NAP drainage management guidelines, information meetings with community groups, WA Channel Management Group (WACMG), CMA's. Technical reports and progress reports as part of EEI program to ACC.
- Information relating to the potential costs of treatment/disposal options will also be communicated to end users
Outcomes and Impact
- Development of cost effective treatment options for disposal of acid groundwater in the WA wheatbelt
- Enable NRM regions and stakeholder groups to develop a consistent approach to acid drainage disposal, with minimal off site environmental impact.
|
