A congressional delegation descended on Paulsboro, New Jersey, Thursday to look into the slow recovery from last week's train derailment and chemical leak.

While the lawmakers say they're disappointed with the pace of the cleanup, responders now say they have passed a big milestone.

When an 84-car train derailed in Paulsboro last week, vinyl chloride leaked from a tank car into the air. Crews are continuing a cleanup at the accident site as more than 150 households remain evacuated.

After getting a briefing on clean up efforts, U.S. Rep. Rob Andrews, whose district includes Paulsboro, still couldn't say when residents can go back.

"The solution to this problem is to get the vinyl chloride out of Paulsboro. Make it so it is no longer a threat," Andrews said. "That process really began in earnest at 11 o'clock on Wednesday morning. It should have begun a lot sooner."

Andrews says with many different agencies working together, but no one completely in charge, the response has been unfocused, hurting the ability to get information to the public.

The Coast Guard has been acting as de facto agency in charge because the accident happened on a waterway. Coast Guard Capt. Kathy Moore said a multi-agency task force has been working to return things to normal.

"We are working swiftly in that direction, deliberately in that direction, purposefully in that direction, very incredibly sensitive to the amount of disruption that this has created and the concerns in the community," she said Thursday.

She said that as of 6 p.m. Wednesday, the vinyl chloride had been removed from the ruptured tank car. Acetone was pumped into the car to neutralize the hazard, and then the mixture was pumped out. Moore says it took a while to announce the milestone since crews have been continuing to clear the area and conduct tests.

A massive crane is standing by to lift all the rail cars from the scene once it's considered safe to move them.

The National Transportation Safety Board investigation into what caused the accident could take much longer. Lawmakers Thursday did not rule out the possibility of congressional hearings.

Accompanying Andrews Thursday were U.S Reps. Frank LoBiondo of New Jersey and Pat Meehan of Pennsylvania.