Revealed: EPA investigation report shows extent of Pilliga contamination

Published: May 05, 2014

The Lock the Gate Alliance says an EPA investigation report into the contamination of an aquifer by Santos’ Narrabri Gas Project in the Pilliga forest reveals how little the Government and the company can do to clean up CSG pollution once it occurs.  The report was released today.

Lock the Gate Campaign Coordinator, Carmel Flint, said, “This report reveals a lot of important information that should have been released to the community over a year ago. 

"It exposes the fact that Santos have added more toxic wastewater to the leaking pond since they took over the CSG project in the Pilliga, and that they first identified problems in May 2012. 

"The report reveals for the first time that not one, but two, aquifers have been polluted - one at 20m depth and another at 35m - and that the deeper aquifer has 4 stock and domestic bores within 5km.

"It shows that the salinity of the wastewater in the dam is almost as salty as seawater and that the shallower polluted aquifer is now extremely saline.

"Perhaps the scariest aspect of this report is that it confirms that CSG wastewater has leached a number of heavy metals out of the soil into the water table - including uranium.

"This means that mobilisation of dangerous heavy metals as a result of wastewater spills is a major risk with CSG activities that has never really been considered before.

"The report also reveals that the EPA did not conduct any independent sampling of their own, but relied entirely on data provided by the company they were investigating - Santos - and that the NSW Office of Water were effectively sidelined from the process.

"There's 170 million litres of toxic wastewater now sitting above those two groundwater aquifers right now and no clear plan to clean it all up.  Attempts so far to 'pump out' the contaminated water from the aquifer have failed, according to this report.

"The big question now is how on earth will Santos try to dispose of this waste if they go to full CSG production with 850 gas wells - do they think they will be allowed to spray this water on our crops, reinject it underground or pump it into our creeks and rivers?

"The NSW Government is should take this contamination incident as a warning about the dangers of the CSG industry - to hit the brakes and stop CSG companies from extracting many billions of litres of salty polluted water they don't know how to manage" she said.

Further comment: Carmel Flint 0400 521 474

Attachment 1:  Timeline   Attachment 2:  Summary of Key Points from EPA Investigation Report


Attachment 1 - Timeline:

January 2011 - Local resident first lodges a complaint about holes in the liner at Pond 2, Bibblewindi Water Treatment Plant[1]

28th October 2011 - Northern Inland Council for the Environment makes a complaint re Bibblewindi WTP and dead vegetation[2]

Late December 2011/Early 2012 - Multiple complaints from local landholders to Santos and the NSW Govt re problems with ponds, liners at Bibblewindi WTP

18th May 2012 - EPA receives letter from Santos re concerns about pond liner integrity[3]

May 2012 - An electrical survey of the liner of Pond 3 by Santos reveals 'a direct connection between the saline water in the pond and the sub grade beneath the liner[4]'.

February 2013 - Bores adjoining the Bibblewindi WTP sampled by Santos[5]

March 26th 2013 - EPA informed by Santos about water sampling results[6]

March 18th 2014 - EPA puts a notification on its website that Santos have been fined $1,500 for water pollution


Attachment 2:  Key Points - EPA Investigation Report: Santos Ltd and Eastern Star Gas Ltd

  1. 1.      There has been pollution of not one, but two, groundwater aquifers. 

'Pollution of two groundwater aquifers (shallow and deep) as a result of leaking ponds at the Bibblewindi Water Treatment Facility...'[7]  The shallow aquifer is located at approximately 20m depth and the deep aquifer at approximately 35m depth[8]

  1. 2.      Santos have added extra wastewater to Pond 3 since they took over the project, and it is still in use as storage for highly contaminated water. 

"The only addition of water to Pond 3 has been the transfer of water from Ponds 1 and 2, to allow decommissioning of these ponds, and small additions from the shut in wells that is necessary to keep the pressure down in these wells."[9]

  1. 3.      The salt levels in Pond 3 are similar to seawater[10], and the shallow aquifer is now almost as saline as the Pond as a result of the contamination.   

The Table on page 3, shows a recorded level of Total Dissolved Solids (TDS) at Bore 12 S of 22,900 mg/L.  Page 3 states that TDS levels in Pond 3 have been recorded at 30,044 mg/L.

  1. 4.      The EPA did not conduct any of its own testing but relied solely on information commissioned and provided by the company under investigation - Santos. 

On page 9, under subtitles 'Pollutes' and 'Cause or Permit', EPA lists the evidence relied upon, and refers only to information provided by Santos or consultants to Santos.

  1. 5.      There are 'four registered groundwater bores that are located within 5km of the site'[11]
  1. 6.      The trial attempt by Santos at so-called 'remediation' by pumping out the aquifer failed, confirming that there is no sure method to address the contamination.

"The results of the trial concluded that recovering the perched water by abstraction in the surrounding shallow perched bores is impractical"[12].

  1. 7.      The NSW Office of Water do not seem to have been given full access to the Technical Report to properly review the risks, despite requesting a copy.

At a meeting between the NSW Office of Water and the EPA about water seepage rates, NOW noted in relation to the 'hydrological definition study' that it 'would need to fully review the documents to be able to provide a full report', but 'As the report was obtained under Notice, the EPA cannot forward this report on'[13].   

  1. 8.      “Vegetation communities surrounding Pond 3 are likely to utilise the shallow alluvial groundwater.”[14]

[1] The Truth Spills Out, A Case Study of Coal Seam Gas Mining in the Pilliga

[2] The Truth Spills Out, A Case Study of Coal Seam Gas Mining in the Pilliga

[3] Page 7, EPA Investigation Report

[4] Page 7, EPA Investigation Report

[5] Page 1, EPA Investigation Report

[6] Page 1, EPA Investigation Report

[7] Page 1, Under section titled 'Allegation'

[8] Page 3, Under section titled 'Issue 1 - Elevated EC and TDS Issues'

[9] Page 5, Third paragraph

[11] Page 5, Under section titled 'Health and Community Concerns'

[12] Page 9, second last dot point

[13] Page 5, under section titled 'Information about the groundwater aquifers'.

[14] Page 8, Under section titled 'Vegetation concerns'

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