DOWNTOWN BROOKLYN — The Con Edison substation where 30,700 gallons of transformer oil spilled into the soil and East River last week had leaked 179 times before, according to Department of Environmental Conservation data.
Although the May 7 discharge was by far the largest one at the Farragut Substation on the DUMBO waterfront — with a conservative estimate of 5,000 gallons of dielectric oil lost in the waterway — the substation had previously spewed more than 8,400 gallons of transformer oil, hydraulic oil and antifreeze into the soil and the river over the years, data from the state's Spill Incident Database shows.
The 179 leaks recorded at that location appear to be more than any other Con Edison facility in the city, according to a review of the state's database, which tracks spills back to 1978.
A Con Ed site on 59th Street and 12th Avenue in Manhattan had the second worst environmental record for the agency, according to the state's database, with 123 spills over the years, and an East Bronx Con Ed location with 66 spills.
In 2016, equipment failed three times at the Farragut Substation, leading to the release of dielectric fluid, the kind of mineral oil spilled on May 7. The largest spill that year took place on April 2, when transformer failure leached 154 gallons of oil into the soil.
In November of 2014, 800 gallons of it went right into the river, records show.
While most of the 179 spills were of small quantifies that didn't make it to the East River, there were several larger spills of dialectric oil over the years including a 2011 spill of 1,000 gallons into the sewer, and spills in 2005 and 1995 where 2,400 and 2,600 gallons of oil dumped into the soil.
"Many spills are small," Con Edison spokesman Allan Drury said about Farragut Substation's history. "We take them all seriously."
When asked about earlier leaks at other Con Edison substations, Drury cited a 2015 transmission feeder leak at a facility in Yonkers that led to the release of 2,200 gallons of dielectric fluid which went into the sewers and towards the Bronx River.
Erica Ringewald, a spokeswoman for the State's Department of Environmental Conservation, said that in the last ten years issues with utility transformers have accounted for 462 spills.
"Clearly big transformers that have dielectric fluid or...synthetic mineral oil, they ought to have by design some containment," said Jon Lipscomb, a boat captain with Riverkeeper.
Con Ed said that each site has its own emergency plan.
"Substations have multiple transformers and each site has a spill prevention plan that is unique to the entire site," Drury said. "Based on this incident, we are evaluating the containment for each."
Synthetic mineral oil, the kind spilled on May 7 into the East River, is considered "non-toxic" by the state's DEC and is less harmful to water quality and wildlife tha petroleum, though it can still harm fish and birds.