Friday 3 July 2015

Wollangambe River severely affected by mine runoff following wall collapse at Clarence Colliery.

The New South Wales Environmental Protection Agency is assessing damage to the Wollangambe River ecosystem near Lithgow in the Central Tablelands of New South Wales, following the collapse of a wall of mine waste at the Centennial Coal operated Clarence Colliery on Thursday 2 July 2015. The river is showing signs of being clearly impacted within 150 m of the incident, which led to several tonnes of coal fines entering the river, and there is concern that the incident could impact the Greater Blue Mountains World Heritage Area, which is less than two kilometers downriver of the incident.

Gully between the waste storage area at Clarence Colliery and the River Wollangambe, now heavily polluted with coal runoff following the 2 July 2015 incident. New South Wales Environmental Protection Agency.

Coal, which in its pure form is basically pure carbon, is not inherently toxic, however fine coal dust presents a number of hazards to the environment. It can coat the surfaces of photosynthesizing plants and algae, preventing them from getting light, and clog the gills and other organs of a wide range of invertebrates. Coal also frequently contains high levels of polycyclic aromatic hydrocarbons, which are toxic and carcinogenic to a wide range of organisms, including Humans. Furthermore it is a source of carbon which some bacteria can use, potentially leading to bacterial blooms and de-oxygenation of closed water systems. Furthermore coal, and in particular coal waste, is seldom pure and frequently contains toxic elements such as mercury or arsenic. Coal waste from the Clarence Colliery is known to be high in nickel and sulphur, both of which are toxic to a wide range of invertebrates. 

The Clarence Colliery was already a cause of concern to the New South Wales Environmental Protection Agency, who earlier this year published a report revealing dangerously high levels of nickel, sulphur, sulphate and calcium in the River Wollangambe, as well as concerns about the levels of zinc, and demonstrated that the river had suffered a 90% drop in the populations of large invertebrates since the mine opened in 1998, which in turn presents a hazard to the areas aquatic vertebrates, including the iconic and insectivorous Duck-billed Platypus.

In the immediate aftermath of the 2 July incident the New South Wales Environmental Protection Agency have ordered the building of a silt wall between the waste site and the river, to prevent any further runoff reaching the waterway, and are carrying out further investigations to determine the extent of the incident and what measures can be taken to restore the river system.

See also...

A worker was killed in an accident at the Glencore Xstrata owned CSA Copper Mine in Cobar, New South Wales, at about 11.15 pm local time on Wednesday 11 June 2014. The worker has been described as a...

Two miners are missing and an unknown number have been injured after a cave-in at the Austar Coal Mine at Paxton in Hunter Valley, New South Wales...

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