Abstract
In 2023, Taseko Mines Limited and Ensero Solutions collaborated on the development, permitting and successful implementation of an in-situ biological treatment within the Gibraltar Mine Tailings Storage Facility (TSF). The primary objective of treatment was to partially reduce the nitrate concentrations in the TSF supernatant to be well-below prescribed discharge water quality standards to enable the restart of permitted seasonal off-site discharge which helps manage the site water balance.
A first of its kind in BC, this innovative treatment approach focused on harnessing naturally occurring denitrifying microbes within the TSF to specifically target and reduce nitrate concentrations through a single application of a food-grade organic carbon source. The application was strategically timed to leverage the natural stratification and seasonal turnover of the TSF to maximize treatment efficacy, resulting in target water qualities to be achieved within the entirety of the TSF.
The treatment was successful in reducing nitrate concentrations to targeted levels (50% reduction) in a short timeframe without generation of any waste by-products, adverse chemistry or legacy infrastructure. The treatment success facilitated the restart of permitted seasonal off-site discharge and demonstrated the viability of levering natural processes to address water quality challenges.
The presentation will outline the successful full-scale treatment implementation strategy which included pilot testing, baseline monitoring, 3D modelling, treatment planning / design, permitting, treatment implementation, and post-treatment monitoring and reporting of results.
The systematic approach taken was pivotal to the success of the treatment process and can serve as a blueprint for others seeking to permit and implement sustainable water treatment processes within their operations.