Press Release - November 8, 2023

Centennial latest project risks Sydney’s drinking water

A water expert has raised concerns that plans by Centennial Coal to discharge contaminated water into the Coxs River near the Blue Mountains will increase salinity and heavy metals within Sydney’s main drinking water supply – Warragamba Dam

Dr Ian Wright, a professor of environmental science at Western Sydney University with more than 25 years’ experience in the industry, has investigated plans by Centennial coal to pump up to 10 million litres of dirty mine water each day from Angus Place coal mine to its coal processing facility at Western Coal Services.

The mine water – which contains arsenic, selenium, ammonia and fluoride – would be combined with other water containing heavy metals then released into Wangcol Creek.

The creek is a tributary of the Coxs River, which flows into Warragamba Dam and provides Sydney’s drinking water.

The proposed projects are integral for Centennial’s plans to expand Angus Place coal mine beneath the Gardens of Stone State Conservation Area.

In a detailed report, Dr Wright says the proposal would lead to elevated levels of salinity, arsenic, zinc, and other pollutants above Australian standards in the Wangcol Creek and the Coxs River and this will cause likely ‘environmental harm.’

Environment groups and lawyers are now calling on Centennial to refer its plans for scrutiny under the Federal Government’s ‘water trigger’ and for EPA NSW to stop giving the mining company a licence to pollute.

Lawyers from Environmental Justice Australia are working with the Gardens of Stone Alliance to raise concerns that the proposed coal projects will impact Sydney’s water supply and endangered plants and animals.

The NSW Department of Planning and Environment is currently assessing feedback on the plans, but environment groups and lawyers say the project may cause serious environmental impacts and must also undergo scrutiny by the Federal Environment Minister.

Under the Environment Protection and Biodiversity Conservation Act, the federal government has the power, known as the ‘water trigger’, to subject large coal mines to a rigorous assessment for the project’s impacts on surface and ground water.  

The Gardens of Stone Alliance is especially concerned that the pumping out of large quantities of mine water may result in the drying-out of and damage to unique wetlands due to a drop in the water table. These wetlands support endangered plants and animals, such as the ‘swamp everlasting’ and the migratory Latham’s Snipe.

Centennial’s terrible track record:

  • In 2010, Centennial was ordered to pay $1.5 million for causing irreparable damage to delicate waterways on the Newnes Plateau
  • In 2017, the mining company was fined more than $1 million by the Land and Environment Court for spilling toxic coal sludge into the beautiful Wollangambe River
  • In 2021, Centennial entered into a $150,000 enforceable undertaking with the NSW Department of Planning and Environment after irreversibly cracking million-year-old sandstone formations in the Mugii Murum-ban State Conservation Area.
  • The projects have been lodged as ‘modifications’ to existing development consents held by Centennial Coal, including the Angus Place coalmine consent (MOD 8) and the Western Coal Services facility consent (MOD 5).

The public submissions will be considered by the Independent Planning Commission, as Centennial has disclosed political donations to the Labor Party and One Nation.

The report from Dr Wright is available here.

Dr Ian Wright said:

“Centennial has been given an unrestrained licence to pollute under an ineffective EPA licence. There’s not effective treatment of the mine and coal effluent and pollutants are flowing into our waterways, impacting ecosystems, and tainting Sydney’s drinking water supply.

The Centennial discharge point is the single most polluting waste water source in the whole Warragamba Drinking water catchment.“

Chris Jonkers, spokesperson for the Gardens of Stone Alliance said:

“Centennial has an atrocious record of underestimating the impacts of mining in this region on nationally endangered wetlands, water quality and million-year-old rock formations.

Their mining activities have destroyed precious federally protected swamps and they just cannot be trusted to properly assess the impacts of these projects on the environment.

Centennial’s plan to pollute Sydney’s drinking water supplies is incredibly concerning. It was only six years ago that successful legal action by the community forced Centennial to build a water treatment plant to stop it pumping contaminated mine water into our catchment.

Centennial needs to explain why its treatment plant isn’t up to the task of treating this additional 10 million litres per day of water – this treatment must occur.“

Environmental Justice Australia Lawyer, Jocelyn McGarity said:

“We’re really concerned that despite the likely significant impacts of these projects on water quality and availability and the fact that they’re integral to the expansion of Angus Place coalmine, they haven’t been referred by Centennial for assessment under our national environment laws.

Given Centennial’s record, we’re not surprised it has misunderstood the water trigger test, but we certainly expect more from the Government.

The ‘water trigger’ power exists because water is vital for thriving ecosystems and communities, and lawmakers recognise communities expect careful scrutiny of large mining projects to properly and thoroughly examine their impact on water resources before giving them the green light.

If Centennial won’t refer the projects to the Federal Government, then the NSW Planning Minister Paul Scully, must absolutely refer them to ensure a thorough assessment of impacts on our catchment.“


The Gardens of Stone Alliance comprises the following conservation groups who work for the protection and better management of the Gardens of Stone region:

  • Blue Mountains Conservation Society Inc
  • Lithgow Environment Groop
  • National Parks Association of NSW
  • Nature Conservation Council of NSW
  • Wilderness Australia.

    If you have a media enquiry, please call or email Jem Wilson on (03) 8341 3110 or [email protected]