Gov. Andrew Cuomo, who visited the facility on Sunday for a briefing, said the fire, which occurred in the nonnuclear part of the plant, resulted in "an unknown amount of oil into the Hudson."
"It appears the volume of oil exceeded the capacity of the holding tank and was discharged into the Hudson River," Cuomo said. "Exactly how much we don't know. That will be part of an investigation."
Crews are working to clean up oil that spilled.
Cuomo said after an initial fire has been put out, the transformer reignited and a second fire had to be extinguished Saturday.
The cause of the fire is under investigation.
"Anything that happens at this plant obviously raises concerns," Cuomo said. "A transformer fire in and of itself was not dangerous, but the fear is that one situation is going to trigger another."
Nuclear Regulatory Commission inspectors and Department of Environmental Conservation went to the plant Saturday night and remained on Sunday.
A plume of smoke was seen in the air after the incident, but the fire never posed any dangers, according to Entergy.
Cuomo praised the efforts of the Verplanck and Buchanan fire department for its quick response. Westchester County police were also on site as a precaution.
"Following the transformer failure an automatic sprinkler system, along with trained onsite personnel, extinguished the fire," Entergy the press release said. "There is no release of radiation to the environment because of this event, nor is one anticipated.
Indian Point's unaffected unit, Indian Point 2 nuclear power plant, continues to operate at 100 percent power, Entergy said.
Congresswoman Nita Lowey (Westchester/Rockland) called for a "swift and thorough investigation" of the incident.
"I remain deeply skeptical that Indian Point's continued operation is in the best interests of families and businesses in our densely-populated region," Lowey said in a statement. "As ranking member of the House Appropriations Committee, I will continue working to help prevent a worst-case scenario for the Lower Hudson Valley and New York City metro area.”
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