HELL'S KITCHEN — A cloud of putrid white gas that left neighbors complaining for days about a rank stench was caused by excessive cooking grease poured down the sewer, officials said.
The smell, which started billowing out of a grate at the corner of West 56th Street and Eighth Avenue on Saturday, was described by neighbors as a mix of feces and chemicals.
The grate leads to a ConEd transformer vault, which was coated in the oily substance.
"There was cooking grease in there that was causing the odor," said Allan Drury, a spokesman for the power company. "Someone dumped cooking grease in the vent."
Neighbors initially suspected that the stench was related to the ongoing cleanup of a heating oil spill at the Sheffield across the street.
Drury added that a crew came to the site on Tuesday night to clean up the site and that the grease — and the smell — was now gone.
It was unclear who dumped the grease down into the sewer or how much was down there.
A spokesman for the city's Department of Environmental Protection said that air inspectors visited the site twice over the past two days and could not find an odor, but could not comment on the cooking oil.