ALBANY, N.Y. (CBSNewYork/AP) — Federal officials have begun questioning Gov. Andrew Cuomo’s plan to use $511 million in loans from a clean water fund to help finance the new Tappan Zee Bridge.

In a letter to the state dated Wednesday, the U.S. Environmental Protection Agency said it was carefully reviewing the proposal, which it called “unconventional.”

READ MORE: Big Brother Hailed As Hero After Saving 4-Year-Old Sister During Fox Attack In Jackson Township, N.J.

The agency said it wants to ensure it is appropriate to use the funds for the $3.9 billion bridge project, and urged state officials to allow public scrutiny of the proposal.

Environmental advocates said the plan would be an improper use of vital environmental funds.

“It’s bad law, bad policy and bad precedent to take half a billion dollars meant for repairing New York’s aging waste water treatment plants and improving our rivers, and using it to pay for basic bridge construction activities,” Hudson Riverkeeper Paul Gallay told WCBS 880’s Sean Adams.

The state’s Environmental Facilities Corp. is scheduled to consider Cuomo’s plan Thursday.

READ MORE: As COVID Pandemic Eases And Restrictions Loosen, Mask Confusion Grows

Cuomo said the loans will fund measures associated with the new bridge to protect the Hudson River and marine life.

The Tappan Zee, which opened to traffic in 1955, is being replaced at a cost of $3.9 billion. The financing largely comes from bonds paid for through higher tolls.

A $1.6 billion federal loan was also recently approved to help pay for the Tappan Zee replacement project, which was on the drawing boards for more than a decade until the White House put it on a list of fast-track projects in 2012.

Check Out These Other Stories From
[display-posts category=”news” wrapper=”ul” posts_per_page=”4″]

MORE NEWS: 'The Late Show With Stephen Colbert' Returns In Front Of A Live Audience Monday Night

(TM and © Copyright 2014 CBS Radio Inc. and its relevant subsidiaries. CBS RADIO and EYE Logo TM and Copyright 2014 CBS Broadcasting Inc. Used under license. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed. The Associated Press contributed to this report.)