The recent dismantling of a coal seam gas (CSG) well adjacent to Casino airport could have been lethal after the explosive ejection of broken drill rods and methane into the air, it was claimed this week.
Mining company Metgasco says no-one was hurt during the well’s decommissioning late on Sunday, July 14, as safety equipment installed on the well to cope with such events had worked.
But Nimbin Environment Centre secretary Alan Roberts said the ‘explosion’ and loud noise as gas burst out under high pressure had alarmed surrounding residents, including those staying at a nearby motor-home park.
Mr Roberts, who is part of a group monitoring the decommissioning of 19 Metgasco CSG wells in the northern rivers, said that during the decommissioning of the well, ‘200 metres of drill rod and milling tool were ejected explosively’.
He said that a Metgasco official, when asked about the incident at the time, told him it was ‘normal to circulate some gas to the mud degasser in the process of killing the well’ and that he could ‘rest assured the well is now dead’ and workmen would ‘soon be running in to commence the abandonment operations’.
But Mr Roberts said, ‘Metgasco may consider it normal, but the well certainly did not, as it shot broken drill rods, methane and liquids skyward in the process of dying’.
He said the NSW mine safety report on the incident shows it was ‘clear that there was a dangerous period between removing the Kingfisher well head Xmas tree and bolting down the Blow Off Preventer (BOP) when the bridge plug could have been ejected possibly into the township of Casino particularly if it were deflected by something.’
‘Also some of the nuts on the bolts holding down some of the Xmas trees being removed have almost rusted away to nothing, allowing the possibility of an Xmas tree to blast off a well into any nearby house,’ he said.
‘People can read the NSW mine safety report and come to their own conclusions as to whether Kingfisher E01 was a cowboy job or not.’
Mr Roberts said there were also other examples of ‘cowboy’ decommissioning jobs by Metgasco in the Casino area.
One was a well at Greenridge, which Metgasco said had been ‘plugged, abandoned and site rehabilitated’, but Mr Roberts said ‘it was clear to everybody that there was still a wellhead in a flooded pit there’.
Another was a well at Rappville that caught fire in 2009 and ‘attended by the Rappville Rural Fire Brigade who were unable to extinguish the huge jet of flame’.
‘The flames were followed by a fountain of froth, according to onlookers, after which a massive mound of earth was piled on the well. It stayed this way for years,’ he said.
But Metgasco managing director Peter Henderson told Echonetdaily that Mr Roberts’s ‘technical and engineering comments and history of the incident are simply not correct’.
Mr Henderson said an incident did occur while decommissioning the well near the Casino airport ‘as indicated in the safety alert the government has distributed’ but ‘no-one was hurt’.
He said the safety equipment, ‘installed to handle events of this type, worked. Government was informed, government officials visited the site and a full investigation was completed.
‘As is normal practice, a “safety alert” was issued to industry so that all can learn from the event. The well has now been decommissioned.
‘As far as the other wells were concerned, there was no fire on the Wyan (Rappville) well; the only flame was from a routine well test.
‘Wyan was decommissioned some time ago (before the end of 2011), the rehabilitation report signed off by the landholder and the associated documents are with government.
‘The Riflebird (Greenridge) well was decommissioned successfully in the first few weeks of July, as part of the current program,’ Mr Henderson said.
Mr Roberts said that, nonetheless, it was ‘sad to see money wasted underground when it could be spent productively on renewable wind and solar thermal above ground.
‘Unconventional gas leaks so badly from every stage of production that its lifecycle greenhouse emissions are worse than that of coal.
‘Metgasco can plug their wells and go away lest our environment is eviscerated and our health destroyed. Neither do we want drill rods, fire and produced water raining down out of the sky,’ he said.