Coney Island residents say ferry construction is causing environmental hazard

Residents in Coney Island say ferry construction going on in their neighborhood is causing an environmental hazard after oil slicks have been spotted on the surface of the water.
The construction is underway to launch the new Coney Island New York City Ferry. It’s been a controversial subject for many residents in this community. 
Some welcome the idea of a ferry in Coney Island as an additional form of transportation but are very upset with the location chosen--the biggest park in the area. 
A rally Wednesday was organized by state Assembly member Mathylde Frontus, and was triggered by slicks of oil that residents say they saw on the surface of the water on Oct. 6. 
Frontus says after she reached out to the city and state about it, the Coast Guard and the DEC came out to investigate. 
She says the source of the pollution is still unclear but may have been caused by a variety of things. 
A spokesperson from the Economic Development Corporation tells News 12, “We have been notified that some residents have observed some debris in the historically polluted creek. Nothing has been observed connected to our activities, and we welcome monitoring by the New York state Department of Environmental Conservation to help us ensure our work has no negative environmental impact on the creek and residents."
Activists say they reject the statement. They say they believe the pollution has been observed after the work on the ferry landing has begun. 
News 12 also reached out to the Department of Environmental Conservation for a statement on their investigation and has not heard back yet.