Homeland Security Department officials are strongly defending the department’s SBInet border surveillance system being constructed at the U.S.-Mexican border, following critical testimony by a Government Accountability Office director two days ago.

The SBInet Virtual Fence prototype, called Project 28, works and is being retooled for other parts of the border, Secretary Michael Chertoff said.

The $20 million Project 28, built by Boeing Co., is a demonstration of technologies that are likely to be used if the department builds an estimated $8 billion border surveillance system in the southwestern U.S.

“We are not mothballing Project 28. It did work,” Chertoff said in a speech Thursday. “There are some things in it that we want to improve, and there are some things that probably it turns out we don’t really need. But I envision that we will use this design in other parts of the border, but not in the entirety of the border.  It works better in certain kinds of terrain, and in other kinds of terrain we’ll use a different approach.”

Chertoff was responding to critical remarks by Richard Stana, director of homeland security and justice issues at GAO, at a congressional hearing Wednesday.

Stana said the initial 28-mile segment of the system does not meet all the needs of its users. Furthermore, Stana said, DHS will delay completion of the next phase of SBInet for three years and will not replicate the prototype elsewhere. Chertoff’s response contradicted that assertion.

Today, DHS officials released another statement about the project, explaining why the department accepted the prototype Press Secretary Laura Keehner said the prototype was designed to demonstrate critical technologies and system integration.

“Specifically, its purpose was to demonstrate the feasibility of the SBInet technical approach developed by Boeing and to show that this type of technology could be deployed to help secure the southwest border of the United States,” she wrote. “The intended objective has been achieved – after successful field testing, we formally accepted it from Boeing last week. We have a system that is operational and has already assisted in identifying and apprehending over 2,000 illegal aliens trying to cross the border since December.”