"He remembered the smell of gas, the explosion and the roof collapsing, " Chadwick said.

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Indeed, the smell of gas was very strong in the area hours after the blast.

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"The smell of gas in Israel has driven people crazy, " he says.

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Large mechanical rollers shape pool-cue sized rods of silver, there's the sound of metal being worked, and the smell of gas in the air.

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People in the area called 911 to report the smell of gas or oil, but the emergency responders didn't find the leak, and were unaware of the pipeline in the area, the report found.

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There was the smell of leaking gas.

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In the case of natural gas, the odor you smell is mercaptans organic chemicals with distinctive odors that make leak detection possible.

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Sepa said the source of the smell is believed to be a faulty gas extraction system at the West Carron Landfill.

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The smell has been identified as that of mercaptan, the chemical added to natural gas to give it an odour.

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