San Diego ? A federal judge on Monday lifted the final legal barrier to completing a border fence meant to thwart illegal immigrants in the southwestern corner of the U.S.

The project comprises 14 miles of additional fencing in San Diego. In September, Homeland Security Secretary Michael Chertoff waived all laws and legal challenges to building the final 3 1/2-mile leg through coastal wetlands to the Pacific Ocean.

The Sierra Club and other environmental groups had argued that Chertoff lacked the authority to do what he did.

But U.S. District Judge Larry Burns said Congress delegated such authority to Chertoff in June.

Litigation has stalled the project since it was approved by Congress in 1996.

The proposal calls for adding two fences to an existing barrier made of Navy landing mats. A maintenance road would be built between the primary and secondary fences, along with lights, sensors and cameras.