HARRISBURG, Pa. -- The parking lot collapse in Harrisburg is causing problems for the city and PennDOT, and the root of the problem has yet to be determined.
Experts have their own theories as to the underlying cause of the disaster.
Dr. Bill Kreiger, a professor of Earth science at York College, said, "My first reaction is sinkholes because there are lenses of limestone up there, and that's where you generally have the sinkholes."
He said there are other possibilities for the parking lot wall's collapse.
"It could've been that the weathering of the structure or the foundation of the building could've caused the collapse," he said.
The area deep beneath the parking lot could be unstable and cause even further problems.
"The structural failure of some buildings in that area can cause as it's falling will cause vibrations that might trigger off something else, so like a domino effect," Kreiger said.
The continuing rainfall could cause more weight on the structures and debris, but Kreiger said it would only be a minor problem and cause further weathering.
He said he won't know for the cause for certain until he can examine the scene thoroughly.
"It's a puzzle and it'll be able to be determined I'm sure," Kreiger said.
The professor will be examining maps and other pictures of the scene to see if he can determine the problem in the near future.