GUWAHATI, June 13 – Serious lapses in the maintenance of the Baghjan gas well could have triggered the catastrophe in the form of uncontrolled flow of natural gas-condensate and the subsequent blaze that is still raging, causing large-scale devastation in the area.
According to eminent geo-scientist and oil well specialist Dr Prodip Saikia, who did an extensive high-tech study of the Baghjan project in 2005 prior to its commissioning, the very logic of declaring it as a gas well was fundamentally flawed, resulting in serious compromises in its safety mechanism and overall maintenance.
“Nuclear magnetic resonance (NMR) technology was used for the first time at the Baghjan exploration site by Oil India Limited (OIL) in collaboration with Halliburton Logging Services and in my assessment report I insisted strongly that it was not a gas well but a condensate – a highly volatile liquid gas – well. My reports that are still lying with OIL will say that it was a rig dominantly producing condensate but my findings were apparently ignored. Drilling and maintenance of condensate gas wells require extraordinary precaution compared to a general gas well,” Dr Saikia told The Assam Tribune.
Dr Saikia, formerly principal petrophysicist at Schlumberger Oilfield Services and a former senior loganalyst at Halliburton Logging Services – two of the world’s top oil service companies, said that OIL had roped in Halliburton to do a high-tech study of the Baghjan gas field before commissioning it in view of some confusion whether it was gas or gas-condensate, and also over its quality.
“I did the entire study and assessment before presenting my report, confirming it to be condensate. You need to be very careful even when the presence of condensate is less but in this well, it was dominant. A couple of senior geologists from OIL did not agree with me and even asked me to modify my report which I never did. A blowout from a condensate well is more destructive and difficult to control than a gas blowout,” he said.
Dr Saikia said that he had warned the OIL authorities against treating the rig as a gas well. “Servicing, work-over, safety measures and overall maintenance of condensate wells differ from a gas well. Condensate wells need two minimum plugs – mechanical and chemical – but from reports on the Baghjan incident, I have learnt that it had only one chemical (cement) plug.”
Since the rig was proclaimed as gas well, Dr Saikia added, it caused serious compromise on safety aspects. “The density of condensate is 0.5 gram as against 0.2 gram for gas. It flows with a much higher pressure compared to gas due to its greater mass and acceleration. The global standards for drilling and maintenance of gas-condensate are higher than those for gas,” he said.
Meanwhile, a senior official with over 25 years of experience in the oil industry said that accidents were nearly always caused by unsafe acts or conditions, and are fully preventable by routine inspections and maintenance.
“Sometimes routine works lead to complacency and that is dangerous. It is, therefore, essential to rotate manpower and keep things under strict supervision. Wells have different layers of cemented steel casings which are subject to corrosion and have a life. The degree of corrosion varies from well to well and region to region,” he said, adding that experienced operators can quickly read the ‘kick’ and prevent it from escalating into a blowout, i.e., uncontrolled release of gas.
He further said that being located very close to Dibru-Saikhowa National Park, a biodiversity hotspot, it was all the imperative that the safest maintenance norms were strictly adhered to in the well. “The efficiency levels of the employees of the outsourced firm maintaining the rig also need to be probed,” he said.
Source:Assam Tribune
