One important life lesson is that when you repeatedly don’t compete a task properly one day the consequences will come back to bite you on the butt. It may take many years but the agents of time, decay, cumulative impacts and the introduction of previously unknown factors makes a habit of doing a shoddy job a high probability to be a big problem in the future.
Career water driller Ian Hansen has been warning for many years of the problem in the waiting with Open mineral exploration holes. Ian first made this call long before what was that previously unknown factor, the coal seam gas industry, became known and just how wide spread it will be. Basin Sustainability Alliance (BSA) committee members received a call for help in an area north of Miles and what was found gives a good case study of the potential problem when you overlay extensive coal exploration drilling with the emerging coal seam gas industry. This is the case of Cockatoo Coal Tin Hut area and the Arrow CSG tenement that now contains the Kedron and Castledean pilot gas fields.
On the 12th September, the day following the launch of CSG Net, a community-based stock bore motoring initiative, south of Wallumbilla, BSA facilitated the visit of Ian Heiner who heads the CSG Compliance Unit and David Free, chief hydrogeologist with the CSG Compliance Unit's groundwater investigation and assessment team (GIAT) to a meeting with a group of concern landowners north of Miles who gathered at the house of Bruce and Pat Hooper.
Cockatoo in a couple of series drilled a 250 metre grid paten in the aim to apply for a mining lease. Following the wet season in 2011 Bruce and Pat Hooper found many sink holes at the drill sites on their property. The original rehabilitation conducted on the Hooper’s property was of a standard observed widespread by different exploration companies in various locations. The PVC which is used as a casing in the upper soil profiles only is broken off most often by a bobcat that digs down a bit and snaps it off, after which the site is levelled.
Image sourced [here]
Cockatoo did respond to the complaints and revisiting the drill sites on the Hooper’s property to conduct further work. Upon completion Cockatoo supplied documentation including a series of photos to show how they were going beyond the legislative requirements to keep the Hooper’s happy. It is rather telling when “world’s best practice” is to cut off the PVC pipe and empty 2 small bags of the pre-mix cement + sand and then fill dirt over it without having added water to the pre-mix cement powder. The Cockatoo document states 87 drill sites were identified on the property of which 16 were not able to be found and 4 more were treated differently because of Arrows Energy were now conducting activity on the property, 2 of the drill holes were in Arrow’s dam area.
Now keep in mind that these drill holes had GPS readings taken and the last series of drilling was only one year prior. What about the many other holes drilled before GPS became available? David Free of GIAT told the gathering that there are 30,000 uncapped exploration holes in the Surat Basin and 100,000 in the Bowen Basin. David also made the statement that, “Whenever you have an open hole unsealed from top to bottom, you are providing a pathway”. BSA believes that this is a very important issue; just what happens when you overlay the mineral exploration activity with a CSG field where the coal measures are depressurised to allow the gas to freely travel. The soil over the top even settled with time will not stop methane. The casing only goes down a few lengths. It allows for the intermingling of any aquifer or small stream above the coal measures.
Arrow has the petroleum tenement over the same area as the Cockatoo coal tin hut area. Already Arrow has two pilot coal seam gas fields; Kedron on the Hooper’s property and Castledean which is just south of the tin hut area.
Responding to BSA concerns in an article published at Beef Central, Abandoned exploration holes must be plugged, the office of the minister for Natural Resources and Mines, Andrew Cripps made the follow statements:
“The drilling of both CSG wells and coal exploration holes has been strictly regulated since the January 1 2005 under both the Petroleum and Gas Act and the Coal Mining Safety and Health Act. “There are also provisions contained in the Environmental Protection Act relating to the proper remediation of coal exploration holes.
“Under this legislation, companies are required to properly remediate disused P&G and coal exploration holes in line with established “plugging and abandonment” criteria, to ensure there is no interconnection between aquifers.”
Amongst the other concerned landowners who came to talk to the CSG Compliance Unit included some whom Cockatoo did not do any rehabilitation on the holes at all. When the drill rig pulled out in July 2010 to when these photos were taken in September 2013 nothing had been done. Cockatoo owns two futher properties in the area and the locals doubt if rehabilitation was conducted on these properties. In the three plus years the wattle has grown back higher than your head and there is a high fuel load of grass thanks to the good summers in 2010 and 2011. Left alone Arrow could develop its full blown gas field with a well 50 metres away or even closer and not be aware of the open exploration holes. The scenario would far too easily develop where this new gas field would depressurise the coal measures making the gas free to move and on the surface a high fuel load experience what is normal in Australian landscapes - fire.
Another life lesson is that if you deny or ignore a problem, it won’t go away
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