Democratic Sen. Bill Perkins, a member of the Public Authorities Control Board, is urging the withdrawal of a $511 million loan to pay for part of the Tappan Zee Bridge replacement project.

Perkins, a Manhattan lawmaker, doesn’t have one of the three votes on the board that can either accept or reject the loan, which is coming from a revolving fund that has traditionally been used to pay for clean-water and sewer projects.

In a letter to Gov. Andrew Cuomo, Perkins writes there are too many questions surrounding the legality of the loan.

“At this stage, there is an entire host of outstanding questions and legal concerns surrounding this project that have not been answered to the satisfaction of anyone, including oversight and expert bodies such as: the United States Environmental Protection Agency (EPA), the Citizens Advisory Committee of the New York-New Jersey Harbor & Estuary Program and the Westchester Municipal Officials Association, not to mention members of the State Legislature and the New York City Council,” Perkins writes.

The board is expected to consider the loan at a meeting in Albany on Wednesday.

Cuomo’s budget director, Robert Megna, as well as Assembly Speaker Sheldon Silver and Senate Finance Committee Chairman John DeFrancisco, each have a vote on the panel that could scuttle the loan.

DeFrancisco, a Syracuse Republican, has not ruled out voting against the loan.

Critics of the loan have charged the governor is using the money to stave off increasing tolls across the state Thruway system in an election year.

Federal officials have also voiced concerns over using clean water funds for the bridge construction.

The Department of Environmental Conservation has responded to concerns raised the EPA noting the loan is both legal, appropriate and not unusual.

Moody’s has called the loan “credit neutral.”

Open Letter to Cuomo RE PACB Final by Nick Reisman