DOVER, Del. -- Delaware transportation department officials have examined aerial images as they investigate a mountain of dirt that grew to about two stories high and 100 yards long over the past few years, possibly causing an interstate bridge just a few yards away to tilt.
Also, DelDOT Secretary Shailen Bhatt told The Associated Press that he ordered immediate inspections of major bridges in the state to determine whether they might be at risk of problems similar to one that forced the bridge closure.
Engineers think that as a contractor dumped more and more dirt next to the Interstate 495 bridge, the ground shifted under the weight and caused the bridge columns to start tilting. The bridge, a bypass that helps alleviate congestion on I-95 through Wilmington, Delaware, and normally carries about 90,000 vehicles daily, has been closed since Monday. It will be at least several weeks before it is reopened.
Gov. Jack Markell planned to visit the site Thursday. As questions mounted, state officials said part of the dirt pile appeared to be on state land, and that a fence that once cordoned off the government's property had been removed.
"In 2012, there was some stuff out there but not very much; in 2013, a little more," Bhatt said of Google Earth images showing the mound grow. "Right now obviously there's a lot more dirt."
Bhatt told the AP that his agency is conducting an inventory of major bridges in Delaware to determine whether the state's property beneath the bridge is properly marked.
The contractor is working with state officials to remove the dirt from the site, which he was allowed to use under an arrangement with a company that leases land next to the bridge.
"I have absolutely no idea what happened, I really don't," said James Thomas Jr., 60. "I'm not a structural engineer. I'm not a bridge engineer."
Officials have said a system to shore up and brace the bridge will have to be designed, which will take weeks. State officials do not have an estimated price tag but have indicated they might seek federal funds to help pay for the repairs.
Bhatt said officials did not know about the dirt mound until Monday, when engineers visited the bridge in response to a report received late last week. That report came from an engineer with a private company who was in the area on an unrelated project and saw cracking in the soil around the dirt pile. The engineer then spotted the leaning columns and contacted the transportation agency.
Built in 1974, the bridge is scheduled for inspection every two years and was last examined in October 2012.
Thomas, who sells the dirt for fill, said he has worked in the area around the Port of Wilmington, just down the road from the bridge, for 41 years, running a paving company and other businesses. He said no one has ever expressed concern about him storing it next to the bridge.
The DuPont Co. owns the land where the dirt is located and leases it out to a materials handing company called Port Contractors Inc.
Thomas's company, Keogh Contracting, has an arrangement with Port Contractors, which was founded by his father, to store dirt on the property.
Michael Evanko, president of Port Contractors, said the company is allowing Thomas to temporarily store the dirt being removed from underneath the bridge on another parcel just down the road.