Small teams of engineers and experts, comprised of about 10 personnel, are on the ground in Yuma, Arizona, and the New Mexico part of the El Paso sector, which also includes Texas, looking at sites, the officials said…

Each assessment should take about seven days. Formal engineering surveys are expected to follow in late April following the award of contracts to builders, which is expected to happen in mid-April.

Actual construction could begin by late May, depending on whether the Department of Homeland Security issues environmental waivers, which is sometimes done to expedite construction. The new construction will be funded by the $1 billion recently transferred by the Pentagon.