Solid Energy’s progress and expertise in managing mining’s impacts on water have been recognised with two recent awards from Water New Zealand. The company (a coal miner) won the organisation’s Ronald Hicks Memorial Award for 2012 for its research paper, Addressing the environmental effects of mining on the Ngakawau River. The award is for an article or paper considered significant in solving or clarifying New Zealand water pollution or sewage treatment problems. Written by Dr Paul Weber, Solid Energy’s Environmental R&D Manager, the paper was presented by Mark Pizey, General Manager Environment. “It’s a great outcome for the company and the mining industry” says Pizey.
Another paper, by Solid Energy Environmental Scientist Fiona Crombie and Dr Weber, detailing research and development of a system to treat acid mine drainage with recycled waste shell from the mussel farming industry, was also recognised by Water New Zealand as a significant contribution to water management.
Both papers detail elements of work by Solid Energy over the last seven years to find and develop sustainable methods to minimise the impacts of the company’s opencast mining on the Ngakawau River in the Buller District. In 2005, after discussions with the neighbouring communities, Solid Energy agreed a set of water-quality measures for the river which it aimed to meet within five years, including ensuring the water chemistry returned to a state which again made the river attractive to migratory whitebait.
The company then embarked on a wide-ranging programme of prevention and treatment at Stockton open-pt mine – changes to the way work is planned and carried out at the mine to prevent or minimise the amount of clean rainwater becoming acidic or mixed with sediment or coal fines, and appropriately treating and monitoring any water which has been impacted by mining before it is released into the Ngakawau River system.
Seven years later the results are encouraging. For some time the company has been regularly meeting or exceeding the water-quality standards, although some challenges still remain with clarity. As well, good runs of whitebait are regularly being reported in the Ngakawau River. A recent fish stock survey by environmental consultants Golders suggests the small native fish are in the river in much larger overall numbers than when a similar survey was done in 2005 and a greater proportion of younger fish are now successfully returning from the sea and making their living in a wider distribution throughout the river and its tributary streams.
“Our licence to mine, the ability to operate in the future as a mining company, is based in large part on our environmental performance” says Pizey. “It’s very encouraging to receive this recognition from our peers in water management and supports our belief that the methods we have researched and developed have wider application here and internationally.”