VISTA GOLD – MT.TODD WATER TREATMENT
Photo: Image of water treatment plant is for represenation only.
Vista Gold Company
AMD Water Treatment
Mount Todd Gold Project
In 2012 Micronised Minerals worked with Vista Gold Company to create a bespoke solution for the treatment and removal of 10.3 giga litres of AMD water in the old mine pit at the Mt.Todd gold project.
Early works included bench testing and reagent design using 1Ltr to 1000Ltr sample sizes. Tests using Micronised Minerals purpose blended reagent resulted in the successful increase in water pH and a significant reduction in metal content as per design to meet water quality objectives.
The refined reagent was then used in a scaled up trial on a 30 Megalitre lined pond at the site. Results of the trial were in line with bench testing and the water quality objectives were met. The success of the large scale trial signaled the green light for the main pit treatment project.
Treatment of the main Batman pit commenced in November 2011 and final polishing to achieve the water quality objectives finished in March 2012. During the treatment project 10,000 tonnes of Calcium Carbonate was used to correct the pH of the AMD water and remove dissolved metals. Final polishing required just 750 tonnes of Quicklime to reduce the metal content to the required levels.
The 10.3 Gigalitres of treated pit water was then discharged in-line with locally determined dilution requirements.