700 miles of border fence whittled down to nearly half.

CONGRESS LAST YEAR PASSED the Secure Fence Act, which authorized 700 miles of double-fenced border barriers.

Critics charged that the law was a bone thrown to voters at the tail end of a remarkably inactive 109th Congress as the border became a hot button issue and immigration reform legislation stalled.

That 700 miles has been cut down to 370, according to Border Patrol Chief David Aguilar.

Gaps will be filled by the virtual wall created by another program, the Secure Border Initiative, he said at a press conference attended by Department of Homeland Security Secretary Michael Chertoff and members of Congress.

The two programs will "morph," Aguilar said.

A letter inserted into the law by Republican lawmakers gave the administration the flexibility to decide where to place the double-fences and how many miles they will extend, according to an analysis by the Migration Policy Institute.

Where the "bricks and mortar" fences go up, and where the virtual fence, guarded by surveillance equipment, is put in place are matters of great concern in border communities. Landowners are expressing fears that the federal government will use eminent domain to take their property.

When asked at the press conference if that mechanism will be used, and what communities might be affected, Chertoff and Aguilar were cagey. Chertoff said it would be a constitutional question.

Rep. Henry Cuellar, D-Texas, said although Congress in the act did specify where it wanted some of the fencing to be installed, he believed lawmakers would allow DHS some flexibility.

"I think the more prudent thing to do is to give the secretary some flexibility where he can look at the terrain and other factors. And I think that is the approach that some members of Congress will be looking at," he said.

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