A sample of wastewater from a Metgasco coal-seam gas (CSG) storage pond has been found to contain high levels of heavy metals toxic to humans and wildlife, according to Lock the Gate Northern Rivers.
Spokesperson Boudicca Cerese said the release of the toxic heavy metals into local waterways via the local sewage treatment plant or onto agricultural lands posed ‘a serious threat to humans, domestic stock and wildlife’.
But Metgasco has stuck to its guns, saying the water is salty and not toxic.
The sample, according to Lock the Gate, was analysed at a nationally accredited laboratory in Lismore and assessed under official environmental guidelines for drinking water standards.
Last week, CSG company Metgasco released its water sampling data showing the wastewater was simply salty, with chief executive Peter Henderson drinking some of its ‘produced water’ from a holding pond to show media that it met drinking water standards.
But Ms Cerese said the pond sample they obtained ‘confirm that there are indeed a range of toxic substances in addition to salts in the wastewater produced in Metgasco’s coal-seam gas operations and stored in ponds around Casino’.
‘The tests found 13 elements present in the sample at levels above the drinking water standards, the majority of them heavy metals. Ten of these substances were also above the allowable limits for maintenance of healthy freshwater ecosystems,’ she said.
‘Aluminium, a neurotoxin linked with the onset of dementia and Alzheimer’s, was detected at 440 times drinking water standards and 800 times the allowable environmental limits. At elevated concentrations aluminium can be lethal to fish and other aquatic organisms and the animals that consume them.
‘Lead, a cumulative poison that can severely affect the central nervous system, was measured at seven times drinking water standards and 20 times the safe environmental limit. Lead is renowned for its effects on children’s development and has been shown to cause cancer in animals.’
Ms Cerese said the results showed the community could not rely on the water quality results provided by Metgasco and there was an urgent need for state government authorities ‘to undertake rigorous independent testing of all Metgasco’s ponds prior to any further actions regarding treatment and disposal of this wastewater’.
‘Plans to use this water in agriculture or to reinject produced water back into the ground are a dangerous notion, one which will backfire on future generations,’ she said.
But Mr Henderson said in a statement to media that his company stood by its results, ‘which summarise results of multiple sampling in different ponds’ and were analysed by certified testing authorities.
‘The analyses we perform are accepted as being appropriate for the produced water and drilling fluid and confirm the water is salty, not toxic,’ he said.