The chairman of the House Committee on Veterans’ Affairs is threatening to withhold money for the VA hospital in Aurora unless the agency provides a detailed account of the project’s billion-dollar cost overrun.

“The bad news coming from the replacement Denver VA medical center never seems to end,” Rep. Jeff Miller, R-Fla., said Thursday. “If VA refuses to account for a $1.1 billion difference, it cannot reasonably expect Congress to pour even more taxpayer money into that black hole.”

At a Wednesday news conference, Department of Veterans Affairs Deputy Secretary Sloan Gibson said people should not expect to see a line-item description explaining how a $604 million construction budget grew to $1.73 billion in barely two years.

“You’re not going to find a dollar-by-dollar account,” he said.

Gibson pointed to an unfamiliar contracting method and an agreement that made VA liable for an affordable design as the two major factors that drove up the cost.

To date, Congress has been provided an estimate that contractor Kiewit-Turner needs $700 million to complete the medical center but no detailed breakdown of the cost increases.

“This stands as yet another example of why the Department of Veterans Affairs’ major construction program is in need of a major overhaul,” Miller responded. “Further, the ongoing lack of transparency across the entire department must end.”

Three members of the Colorado congressional delegation also called for answers.

“When I was in the Marine Corps, if someone lost a $100 radio there was hell to pay,” said Rep. Mike Coffman, a Republican. Meanwhile, the VA won’t hold itself accountable for wasting over a billion taxpayer dollars.”

Sen. Michael Bennet, a Democrat, also expressed frustration Thursday with the VA’s inability or unwillingness to detail the specific reasons for the overruns.

He now expects answers, however, from a different federal agency.

“We still need more clarity on what went wrong and a specific accounting of how $600 million turned into $1.7 billion,” Bennet said in a statement.

An amendment he passed with Sen. Cory Gardner, a Colorado Republican, instructs the U.S. Government Accountability Office “to begin an investigation that will help us get to the bottom of this,” he said. “We need to know where this money went.”

Gardner agreed. “The American people can’t get away with telling the IRS that they’re unsure of their income, yet the VA thinks it can get away without providing an explanation as to where over $1 billion worth of taxpayer money went,” he said. “I hope this isn’t the final answer.”

David Olinger: 303-954-1498, dolinger@denverpost.com or twitter.com/dolingerdp