We take our commitments to the environment very seriously and operate to reduce long-term impacts. Our objective is to transition from mining land use to the next sustainable land use, thereby supporting the relinquishment of our mining leases.
The Isaac Plains Coal Mine operates under an Environmental Authority (EA), which was first granted in 2006 by the Queensland Government for mining activities to be undertaken within ML70342. The EA sets our the environmental monitoring requirements and regulatory limits which must be met or bettered in order to continue to mine coal whilst protecting the environment. The EA was amended in 2018 to incorporate the new Isaac Plains East mining operations and in 2019 to incorporate the Isaac Plains Underground project.
Isaac Plains Coal Mine monitors the following environmental activities:
- water (potable, mine-affected water, natural creek flows, water releases, groundwater, receiving environment)
- dust (personal, depositional and real-time air monitoring)
- noise and vibration (real-time monitoring at three locations to the west and south of the mine site)
- rehabilitation (recontoured, topsoiled and revegetated landforms)
- coal rejects disposal within mining voids (waste from the mining process)
- dam integrity/stability
- waste (general, recyclable and and regulated)
- social impact
The site water management system is comprised of sediment dams (for sediment laden water runoff from spoil dumps), release dams (for releasing water to the environment in accordance with EA requirements), a raw water dam (for storing the allocated raw water supply), and a drainage system which allows for clean water run-off collected by the catchment to be diverted away from the active mining areas.
Maintaining an appropriate water balance is a key challenge faced by all mines - to ensure the site has enough water storage capacity for wet season or flash flood events but at the same time does not run out of water for activities such as coal processing and dust suppression. At Isaac Plains, a site water balance model has been developed by specialist water engineers. This model is updated and calibrated on a regular basis to ensure water inputs and outputs are accurate.
This model allows us to run extended dry or wet period scenarios. The data generated is then used to improve water management processes and systems on site.
At Isaac Plains, we undertake rehabilitation on a progressive basis with consultation between the environmental, technical services and production teams. All rehabilitation is carried out with future land use in mind. Our aim is to return the site to grazing pasture.
The rehabilitation objective for Isaac Plains is to create a safe, stable and sustainable landform using cost-effective spoil placement methods.
Profiling of the external out-of-pit spoil dumps is completed to a slope of no greater than 15% (in compliance with the EA). All surfaces are topsoiled, contour-ripped and sown with the nominated native flora species and pasture species using both tractor and aerial seek sowing methods.
Rehabilitation is viewed as an integral part of the mining process. Stanmore is committed to progressive rehabilitation of the site in order to continue to mine and operate in a socially conscious way, as well as drive down our financial assurance and future closure costs.
Since the acquisition of the Isaac Plains Mine, Stanmore has topsoiled and seeded more than 300ha, with an additional 200ha of rehabilitation planned by the end of 2020.
The waste management hierarchy employed at Isaac Plains begins with waste avoidance as the number one objective, followed by waste re-use, waste recycling, energy recovery from waste, with waste disposal as a last resort. Regulated waste, batteries, waste oil and recyclables (e.g. cardboard, paper, glass and aluminium) have designated receptacles that allow these waste products to be recycled. Waste oil is also recycled for use in explosives for blasting.
Monthly reports generated by our waste service provider allow the environmental team to track volumes of waste and identify areas for improving the site waste management system.
Real-time monitoring of environmental parameters allows us to respond quickly and effectively to potential environmental nuisances caused by our operations before they reach the allocated EA trigger levels. Alerts are linked to a range of site shutdown procedures and notification is sent to site representatives to implement appropriate abatement measures.
The real-time monitoring equipment located on and around site includes eight 'DuskTrak' units and two Spirant BAM 1020 monitors to allow for the real time monitoring of PM2.5 and PM10 dust, seven automatic ISCO water monitoring stations, two automatic weather monitoring stations, and two vibration and overpressure monitors for blast monitoring.