Background
SGME was engaged for our services to conduct sampling, analysis and review of a waste rock dump (WRD) to determine the potential for acid mine drainage, neutral mine drainage and / or saline drainage. The mine comprises five satellite operations which produce copper, silver, gold, lead and zinc near Cobar, New South Wales. Waste rock has been stored in a dump adjacent to a pit at one of the satellite operations. The WRD is the primary source of material for future rehabilitation work on the tailings storage facility (TSF).
Objective
Two geochemical sampling programs were executed on the WRD to evaluate its geochemical composition, identify areas needing management interventions and validate the balance of non-acid forming (NAF) waste rock. These initiatives led to the identification of specific zones within the WRD flagged as potentially acid-forming (PAF), making them unsuitable for rehabilitation purposes. However, due to the immediate need for NAF waste rock from the WRD to complete a lift on the TSF, a rapid on-site assessment became necessary. This assessment was crucial as the waste rock underwent crushing and screening to ensure that only NAF waste rock was selected for use, thereby minimising environmental risks and ensuring compliance with the environmental licence.
Solution
Engaging SGME for field testing services to conduct sampling, analysis and review facilitated regulatory compliance with the environmental licence and implementation of waste management best practices. Geochemical analyses were used to establish thresholds for total sulfur, upper pH and electrical conductivity limits. Field screening criteria were derived from assessments of over 1,000 samples which underwent acid base accounting and sequential net acid generation testing.
During the crushing and screening operations, SGME provided safe and essential field services by conducting daily analyses of representative samples using handheld x-ray fluorescence, pH and electrical conductivity measurements. These analyses were instrumental in determining whether the past 24-hour period of crushing and screening yielded NAF or PAF waste rock.
SGME’s assessment enabled informed decisions. The mine had the ability to segregate PAF waste rock for disposal underground, thereby creating space on the run-of-mine pad. The NAF waste rock was transported to the TSF for stockpiling to ensure compliance with the environmental licence and waste management protocols.
Engaging SGME for field testing results in precise data collection and real-time insights. We will deliver our services in a way that is cost-effective, customised and aligned with regulatory requirements to enable informed decisions, support operational efficiency and maximise savings for your project.
