WASHINGTON (CN) - Eminent domain, sky high costs and infrastructure overhaul dominated a senate hearing devoted to tackling one of President Donald Trump's biggest campaign promises: an extensive wall along the U.S.-Mexico border to keep out undocumented aliens.
The exact price tag for the wall is unknown. Estimates have ranged from the millions to the billions and during an oversight hearing Tuesday, the Senate Homeland Security and Government Affairs Committee found itself no closer to a definitive answer on cost.
Senators agreed that a pending report from the Department of Homeland Security will help shape the budget.
In the meantime, Sen. Claire McCaskill, D-Mo., tossed out an estimate she says she from a Senate briefing by U.S. Customs and Border Protection officials.
"The wall that President Trump promises could cost nearly $70 billion. That works out to $200 for every man, woman and child in the U.S.," McCaskill said. "I'm not sure that's a cost that American taxpayers are willing to bear. Especially when they were told Mexico would pay for the wall and not the American people."
Twenty million dollars has already been spent on prototypes of the wall. Those funds came directly from a pool of funds border patrol agents only recently said was depleted and needed an infusion of cash.
It was originally earmarked to pay for advances in surveillance technology, additional fencing and personnel which reinforce any efforts by agents to combat drug smuggling, illegal crossing and even helps agencies to better preserve delicate ecological systems on the border through smarter, lower impact technology.
Sen. Heidi Heitkamp, D-N.D., urged prudence when it comes to discussing the wall and tried to dispel the notions that the wall would be a single long cement border reaching into the sky.
Terrain changes from region to region would change the physical structure of any fence or wall, she said. And these variables would impact the final budget.
Another unknown factor in eventual cost of the wall is the cost of doing business with private land owners in the region. Two-thirds of the land along the U.S.-Mexico border is either privately- or state-owned. And some of that land has been held by individual families for generations.
Customs and Border Protection officials estimated that in 2008, the last time the agency contemplated replacing large sections of the existing border fence in South Texas, 400 privately owned parcels of land stood in the way. The federal government eventually acquired almost all of those properties, but in 330 cases it was forced to file condemnation lawsuits.
Of those lawsuits, over 90 are still pending nearly a decade later, a red flag for cost and timeliness for feds.
"That's eminent domain. If you say that word in rural Missouri, you better run. Because someone's going to have their shot gun out," McCaskill said.
Officials estimated that to date, about $78 million has been spent on the fence-replacement effort, and committee members said it might cost another $21 million to resolve the pending condemnation lawsuits, figures that gave McCaskill pause now that the government is looking at creating Trump's border wall.
"No one can tell me how much it will actually cost to seize the land," she said in frustration.
All three experts who testified before the committee said no matter how big the border wall is or how it is configured, more staff and better technology will still be required to deter illegal border crossings.
David Aguilar, a former acting commissioner of U.S. Customs and Border Protection, told the Senators that no matter what the wall eventually looks like, at t he end of the day, it will still be a border that's main purpose is to deter or impede individuals wishing to enter the country illegally.
"The purpose is to ... create more time for officers to responsibly react and take action," he said.
Read the Top 8
Sign up for the Top 8, a roundup of the day's top stories delivered directly to your inbox Monday through Friday.