MINNEAPOLIS -- A road crew supervisor who survived the Interstate 35W bridge collapse in Minneapolis insists none of his workers felt any unusual wobbling or swaying before the span plunged into the Mississippi River.

“During all of my time on the I-35W bridge, I did not notice any unusual or unexpected swaying or rumbling,” said Steve Weston, a project manager with Progressive Contractors of St. Michael, Minn. “No one in my crew made any such report to me. Right up to the collapse, I had no reason to believe that my crew and I were in danger.”

The firm also stated it has completed its own “intensive review” of the work.

“There’s nothing we did during our work that should have contributed to the collapse,” Weston said. “We’re as shaken and baffled by the collapse as the motorists on the bridge that day.”

Weston was part of an 18-member crew on the bridge when it crumbled Aug. 1. He said he was lucky to survive. One worker, Greg “Jolly” Jolstad, 45, is one of eight people who remain missing.

The firm's work has become one focus on the National Transportation Safety Board’s investigation into the collapse. U.S. Transportation Secretary Mary Peters warned states Wednesday to take precautions about added stress placed on bridges during repair work.

Progressive Contractors was resurfacing the bridge deck as part of a $9 million state contract. The project was about 70 percent complete, said Liz Benjamin, a state construction engineer overseeing the work. The job mainly entailed grinding off the top 2 inches of the road’s surface and repaving with new concrete.

Crews also replaced a series of expansion joints, which are narrow breaks between slabs that allow concrete to expand and contract with the weather.

In addition, workers searched for areas where the concrete was eroded below the surface. When they found such spots, they used jackhammers to remove all 9 inches of the concrete deck.

By July 31, the contractor had completed work on two lanes in each direction and had begun working on two of the four remaining lanes. On Aug. 1, the day of the collapse, crews spent much of their time using 45-pound jackhammers to remove concrete from various weak spots, Benjamin said.

Plans for that evening had called for workers to begin resurfacing two lanes. They had heavy equipment and roughly 100 tons of sand and other material used to make the concrete staged on the bridge.

The Minneapolis Star Tribune reported this week that road crew workers told a rescuer shortly after the collapse they had felt “wobbling” on the bridge. Progressive Contractors officials said none of the surviving crew members stated they had noticed such unusual movement.

Weston said many drivers “may not realize that every steel bridge sways to some extent.”

Progressive Contractors, founded in 1971, has done extensive work for the Minnesota Department of Transportation and other public agencies.

“We continue to believe that our concrete repair work was routine, that it was done well, and that there was nothing about it that should have caused a bridge to collapse,” said Tom Sloan, a Progressive Contractors vice president.