That is not correct. No new border wall construction can occur under the omnibus, which is now law.
The Army Corps of Engineers fall under DoD, and the Dod is prohibited, by law, in this legislation of construction any new border wall. All they can do is repair existing fencing.
It's in the bill. If Trump tried to go around the very law he just signed, it is an impeachable offense (for real).
Exacting on what page does the bill say that?
In the military, one cannot use new money to tear down and rebuild a current structure without authorization. However, according to the Regs in the USAF, an old building may be ‘renovated’ as long as part of the original structure remains. They have been tearing down buildings until only one corner is still framed and totally redesigning the structure using that one corner as the cornerstone of the building.
Not new, simply a renovation. Leave one fence post on each coast and renovate the border wall from sea to shining sea. A military self help project expending training dollars to train soldiers, sailors, and airmen on using heavy equipment and combat construction technology and modern equipment. After construction the fence would be signed over to the border patrol as in a public park project done the same way by the guard and reserve all year long every year.