RICHMOND — U.S. Sen. Mitch McConnell and U.S. Rep. Ben Chandler wore hard hats and orange safety vests Tuesday as they toured a construction site where chemical weapons eventually will be destroyed at the Blue Grass Army Depot.

McConnell and Chandler told reporters, who were allowed to visit the Blue Grass Chemical Agent-Destruction Pilot Plant for the first time Tuesday, that they were pleased with the progress of the project.

McConnell said he expects chemical weapons to be destroyed by 2017, the deadline imposed by Congress. The Pentagon, however, has said Kentucky will be the nation's lone stockpile to miss the deadline, with the destruction process starting in 2019 and finishing in 2021.

"I don't think we've ever been as close to seeing this done as we are today," Chandler said.

McConnell said there is a real danger as long as the weapons, which never should have been created, exist. But he said he was pleased with the progress being made to correct the problem.

"This is one of history's great mistakes," McConnell said.