Riverhead residents are expressing hope after the Navy launched a new interim treatment system aimed at addressing part of the groundwater contamination plume that originates from the former Navy site in Calverton.

The plume has been a concern for decades after chemicals entered the ground at the former Navy property.

Residents and environmental advocates have long pushed the Navy to take action to remediate the contamination, which they say threatens drinking water supplies and could impact local rivers and lakes.

"For years now, it's been moving and it's affecting people's drinking water. And it may pollute the rivers and all the lakes around here. It's a good thing that they're starting to clean it up," said Riverhead resident Brian Hanlon.

The Navy accelerated its response to PFAS contamination several months ago. Within 120 days, it built two extraction wells that are currently filtering PFAS chemicals from the groundwater.

Environmental advocates say the project is an encouraging development but stress that additional work is needed.

"We are encouraged that the Navy is now showing signs of hearing our calls to expedite the cleanup plan for the PFAs chemicals. That's a great first step. We need them to keep it up and keep going and not take their foot off the gas pedal," said Adrienne Esposito, of Citizens Campaign for the Environment.

Residents who have followed the issue say the cleanup effort is overdue but welcome the progress.

"I think it's great. I think it should have been done a long time ago, But they dragged their feet. At least they're doing it. Doing something is better than doing nothing," Hanlon said.

Jack O'Connor, of Bayport, echoed that sentiment.

"The best time to do anything is, you know, yesterday, the second best time is today. So it's great that they're doing it now," O'Connor said.

Superintendent of the Riverhead Water District Frank Mancini also welcomed the development, while noting that more work remains. In a statement, Mancini said: "This new system is not going to be the permanent solution but it's a great start and a step in the right direction after years of delay and inactivity."

Residents and advocates say they hope the interim treatment system marks the beginning of broader efforts to continue cleaning up the environment and addressing contamination from the Calverton plume.