The pioneers in progressive mine rehabilitation is one of the greatest assets in departmentalizing mining stereotypes. Environmentally friendly procedures and more and more miscellaneous ecosystems are becoming the standard as companies regard local ecosystem rehabilitation as a part of the on-going mining process.
To better understand these progressive rehab techniques, here are some words from Idemitsu Australia Resources Corporate Sustainability and Environment Manager Dr. Jan Green and Parsons Brinckerhoff Team Manager, Alex Cockerill.
“There’s an increasing focus on establishing complex and diverse natural ecosystems as part of mine rehabilitation,” she says. “With progressive rehab, it takes a much shorter time after the mine closes before the original flora and fauna can take over naturally.”
Her existing project is a 6- to 7-year-old mine that will sooner or later go back to a box gum woodland with white box gum trees. She explains that one of the biggest challenges is keeping up with the mining as it happens.
A strict schedule of clearing between summer and autumn allows species, for example, to nest in the winter and raise young in the spring. Cockerill says the team salvages hollow logs and timber for the provision of supplementary fauna habitats within the rehabilitation, and collects the seeds of local species of plant from the adjoining forest for propagation in a nursery.
By means of local species, it provides them a better chance of growing for the reason that the topsoil is recreated with greater accurateness. Sequentially, local fauna, from invertebrates to birds and mammals, are attracted to familiar landscapes.
“With the progressive establishment of increasingly complex vegetation structure and diversity these ecosystems encourage more local species back onto the mine site,” Cockerill explains.
“It’s then supported by biodiversity monitoring to target measurable performance criteria throughout the life of the mine and rehab,” Dr. Green says.
Dr. Green believes progressive rehab should be the norm and there’s good reason for that.
“We are mining in a state forest and to rehabilitate progressively is part of the approval conditions,” she admits, “But progressive rehab is better in terms of the environment and community acceptance.”
Deserted mines and plateaued soil heaps are not natural and can take expanded time to renew because of erosion. But gradually rehabilitated mines have extra defiance to erosion. This is because spoil piles are benched with draining slopes and layered with mulch.
“Importantly, progressive rehabilitation limits the time the ecologically valuable topsoils are stockpiled”, Cockerill says. “Reusing these topsoils progressively will maximise the survival of soil biota and the potential natural regeneration from the forests, soil and seed bank.”
But the biggest challenge may be communication. It is difficult to fight misinformation, especially when it comes to mining and the environment explains Dr. Green. “The most important thing you can do is to engage with the local community, the regulators and interested groups to design and deliver a landscape that everyone has had the opportunity to discuss,” she says.