"I think many human beings are just going to remain unemployed under this plan," he said.

"This is jobs for robots," added Rep. Raul Grijalva (D-Ariz.).

The two Democrats were talking about H.R. 1904, which would let a foreign-owned mining company, Resolution Copper Mining LLC, swap land with the federal government so it can mine for copper on what is now the Oak Flat Campground. Because the company is part-owned by Rio Tinto and BHP-Billiton, Democrats say the new mine might rely heavily on robotics, since Rio Tinto is known for pioneering this technique.

Republicans dismissed that concern.

"Does anyone honestly believe that passing this bill would create jobs only for an army of robots?" asked Rep. Dan BenishekDaniel (Dan) Joseph BenishekRepublican groups launch final ad blitz in key House battlegrounds Tea Party class reassesses record Michigan Republican to retire MORE (R-Mich.). "Are you kidding me? Robots?"

"C'mon, this isn't the Jetson's doing this," Rep. Jeff FlakeJeffrey (Jeff) Lane FlakeCorker pressed as reelection challenges mount -trillion debt puts US fiscal house on very shaky ground Senate votes down Paul's bid to revoke war authorizations MORE (R-Ariz.) said to his Democrat colleagues. "These are all real people, not robots. You didn't hear me say C-3PO."

Rep. Paul GosarPaul GosarHouse votes to block funding for EPA methane pollution rule McCain needs to start showing my constituents more respect Fresh Freedom Caucus demands stall GOP budget MORE (R-Ariz.), the main sponsor of the bill, tried to address both the robot concern and worries that the mining site would displace Apache Indians who now use the land in question. He cited Chris, an employe of the current site and a member of the Apache tribe.

"Chris is not a robot," he said.

The House began debate on amendments to the bill at about 2:30 p.m., and planned votes on these amendments and the bill later Wednesday.