Long Island Power Authority Chairman Howard Steinberg has resigned from the board of directors of the troubled agency.
Steinberg resigned in a letter saying his private sector responsibilities preclude him from being able to devote the time needed to address the challenges at LIPA, according to a LIPA source.
The resignation is effective immediately. Gov. Cuomo's office would not confirm or comment on the matter.
His exit Friday is the latest in a string of departures following criticism of LIPA's performance in the wake of Sandy.
Steinberg's resignation follows those of LIPA chief operating officer Michael Hervey, trustee X. Christofer Damianos and vice president of customer service Bruce Germano.
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Steinberg was appointed by Gov. George Pataki in 1999.
The utility is being investigated for its performance after Sandy. More than a million customers lost power, and some remained in the dark for more than two weeks.