BEN CUBBY August 01, 2012
Low risk ... mining and coal seam gas drilling are unlikely to case widespread damage to fresh water supplies in north-west NSW, a report says. Photo: Reuters
MINING and coal seam gas drilling are unlikely to cause widespread damage to fresh water supplies in north-west NSW if they remain at current levels, says a report that attempted to model some the long-term risks of the resources boom.
The state government commissioned the independent Namoi water catchment study to estimate the cumulative effects of many mining and drilling developments on water across a whole region.
The results suggest many of the proposed coalmines and gas fields would be unlikely to strip farmers in the state's main food bowl of the water they rely on to grow food, though the researchers said there was uncertainty around some of their conclusions.
But there would be some continuing risks of damage to the aquifers that maintain the rich soil of the Liverpool Plains, and the possibility of river contamination and isolated pollution.
''At current levels of development, extensive regional scale impacts on water resources are unlikely,'' the report's authors found. ''More local scale impacts are likely and the cumulative effects of numerous developments in close proximity will increase the risk to the water resources in those areas.''
The study, conducted by Schlumberger Water Services, was the first attempt to model the effects of industry on an entire water catchment.
It looked at a range of scenarios for the impact of resources projects on the Namoi River and its tributaries, including variations in climate and rainfall. Generally, more mines meant more pressure on fresh water supplies. The study was commissioned partly to address concerns that the rapid expansion of both the coalmining and coal seam gas drilling industries would undermine long-term agricultural productivity.
The Resources Minister, Chris Hartcher, said the report showed mining and farming could coexist if managed carefully.
"Further, the study determines that even under extreme hypothetical scenarios of substantial industry expansion, the potential impacts of coalmining and gas extraction are low when compared to existing water drawdown from existing uses,'' he said.
The NSW Farmer's Association said the study confirmed its view that the state needed well-policed policies to protect agricultural water supplies.
Its president, Fiona Simson, pointed to one of the findings that "at a project scale, mining and [coal seam gas] activities both had the potential to negatively impact groundwater and surface water resources".
"It also confirms our view that similar studies need to be initiated urgently in other areas of the state so we can make informed decisions about the future of mining and [coal seam gas] in those areas,'' she said.
The NSW Minerals Council welcomed the ''encouraging'' findings. "Despite making assumptions that overestimate the likely impacts of coalmining on water resources in the region, information we have seen as part of the study demonstrates that the cumulative impacts of mining are likely to be within the historical impacts of agricultural water use across the region," said its chief executive, Stephen Galilee.