SPRINGFIELD — U.S. Rep. Richard E. Neal led Massachusetts Lt. Gov. Karyn Polito through the now-empty passenger tunnel at Springfield's Union Station on Monday following a news conference.

"You can imagine what a beehive of activity this once was," Neal, a longtime advocate for the rehabilitation of the 89-year-old depot, told her. "This would have been full of people."

A study of east-west rail is expected to be completed by the end of this year.

Connecticut has a $365-million project to enhance its north-south service from New Haven to Hartford and on to Springfield. That service could add 14 to 16 trains a day to Springfield, although Connecticut Gov. Dannel Malloy has accused Amtrak of dragging its feet on the project, making it more expensive, according to reporting last week in the Hartford Courant.

Last year, Amtrak returned service to the Connecticut River Valley.

At the Union Station site, workers are now driving piles for the six-floor 377-space parking facility that will front Main Street at the site of the old Hotel Charles.

Workers are also building outdoor bus bays, said Robert J. Aquadro, project manager for Daniel O'Connell's Sons. Work is also ongoing on the elevated railroad tracks now used by Amtrak and by CSX.

All the interior demolition of the station itself has been completed.

The next job will be to waterproof the tunnel leading from the grand concourse under the tracks so it can be reopened to the public. The tunnel access stairways and elevators to the track side will also open the building up to Lyman Street.