An inquiry committee, headed by Joint Secretary (Refineries) Rajesh Kumar Singh, in a report submitted last week concluded that negligence caused the fire at the Tatipaka-Kondapalli pipeline on June 27.
Sources said the committee found that the pipeline had corroded due to condensate and water that came along with the natural gas from an Oil and Natural Gas Corp field.
Water corroded bottom of the pipeline, causing pores in the underground pipeline. Gas was being transported at high pressure and it leaked along with flammable condensate leaked out to the surface on the night of June 26/27. Overcast weather lead to a cloud of gas being formed even as condensate sprayed on the ground.
A spark, possibly from a cigarette or bidi lit by a local, at 0545 hours on June 27 led to condensate and cloud of gas catching fire with a loud explosion.
The other source of the massive fire is being mentioned as a tea vendor lighting up a stove in the vicinity of the leak, scorching everything in a radius of about half a km, including houses and vehicles, in Nagaram village of East Godavari district.
The exact source may not known as everything including the persons were charred, sources said.
Sources said gas should have been stripped of waste and condensate at GAIL's Nagaram facility before being pumped into the pipeline for transportation to a power plant.
The gas sales and purchase agreement between ONGC and GAIL has no mention about the quality of gas. ONGC believes stripping of gas was GAIL's responsibility while the gas utility feels otherwise.
Sources said following the accident, GAIL has decided to put separators at gas sources in the Krishna Godavari, Cauvery and Cambay basin. GAIL has reduced pressure at pipelines in Andhra Pradesh, Tamil Nadu and Gujarat and is carrying out thorough checks.
Any pipeline which is found to have been corroded or is more than 15 years old is being replaced.
Following the accident, GAIL has suspended officials responsible for the safety of the pipeline passing through the populated area. It suspended General Manager Pankaj Patel and Deputy General Manager Rakesh Kumar.
"Pending the outcome of the inquiry set up by the government as well as the company, two senior officials in charge of regional operations and maintenance of the pipeline network have been suspended," GAIL had said in a statement on June 29.
Under a 2006 agreement between ONGC and GAIL, the latter is responsible for removing condensate and water, which corrode the pipeline because of high presence of sulphur.
The 18-inch pipeline carried gas from state-owned ONGC's gas field in the East Godavari district.
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