The quality of the water running through the disused Berrima Colliery has improved significantly over the past nine months, according to Boral.
A Boral spokesman said this improvement was a result of the installation of an interim underground trial treatment system by the company.
The mine, which had been in operation for more than 100 years, was placed in a care and maintenance mode in October 2013, suspending coal extraction.
Since then, Boral worked closely on an agreed closure plan process for Berrima Colliery with the NSW Environment Protection Authority (EPA), the NSW Resource Regulator, and other relevant state and local agencies and with experts such as Dr Ian Wright, of the School of Science and Health at Western Sydney University.
The Boral spokesman said the process included the ongoing monitoring and testing of the groundwater that ran through the now disused mine.
“Boral believes we have made progress on this front, especially since we started trialling an interim underground water treatment system nine months ago,” he said.
“Since the installation of the trial treatment, there has been monthly testing at the discharge point and at agreed locations downstream of the mine, conducted and analysed by an independent laboratory.
“Those tests have found a general trending down of the metals of concern and a noticeable improvement in the visual appearance of the Wingecarribee River within the mixing zone downstream of the colliery’s discharge point.
“The latest testing, conducted in September 2018, confirms that metal concentrations, such as dissolved iron, within waters released from the mine discharge has dropped by 78 per cent since December 2017.”
The spokesman said Boral had also requested a variation to its Environmental Protection Licence, requesting an extension of time when submitting progress reports.
He said this would allow more time for the consultants to complete and synchronise the water sampling at the collection sites, as required in the Licence Performance Monitoring Program.
“We want to acknowledge the support of the Closure Working Group, which includes five community representatives and members from relevant government agencies.
“We want to ensure the closure of the mine reflects a best-practice model approach, informed by scientific data and advice from leading experts.”
Minutes and presentations from these meetings are available on Boral Berrima Colliery webpage.
Boral will provide further regular updates.
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