The Department of Homeland Security announced Thursday that it had chosen four vendors to build prototypes of the border wall that will be made from reinforced concrete. Four other vendors that submitted proposals for alternative building materials will be announced at a later date.

Caddell Construction Co. of Montgomery, Alabama, Fisher Sand & Gravel Co. of Tempe, Arizona, Texas Sterling Construction Co., of Houston and W. G. Yates & Sons Construction Company of Philadelphia, Mississippi were selected.

The prototypes, which will be 30’ tall by 30’ wide, will be built in the San Diego area. Construction will begin in a few weeks and each company will have 30 days to finish their project.

Once they are finished, border experts will test the walls for aesthetics, anti-climbing features, resistance to tampering and penetrability with small hand tools. Contractors are also required to account for other technological features, like sensors, cameras and lighting, that would accompany the physical walls. “There’s a more holistic view here,” Vitiello said. “This is a much safer environment than what we’ve planned for before.” After testing, Border Patrol may choose to leave the structures in place, move them or get rid of them, Vitiello said. (The San Diego Union Tribune)

While Border Patrol will be monitoring the area the companies will be building the prototypes in given the proximity to the border, they are required to provide their own security, according to Joshua Wilson, spokesman for the San Diego chapter of the National Border Patrol Council.

“There has been a lot of planning that’s gone into this,” Wilson said. “All the appropriate measures are being taken.”

The contracts for the companies to build the prototypes range from roughly $400,000 to just under $500,000.