SAN LUIS OBISPO, Calif. - The excavation project to search for the remains of Kristin Smart is now officially underway. On Wednesday morning, more than two dozen members of the FBI's Evidence Response Team began the difficult task of searching three locations on the Cal Poly hillside where the San Luis Obispo County Sheriff's Office believes Smart may be buried.

"We're in the process of excavating those sites to see if we can find anything of evidentiary value," said FBI Special Agent Tom Brenneis, Senior Team Leader Los Angeles Division Evidence Response Team. "Obviously human remains would be the best event for us, but there could be other things too that are pertinent to the case."

On Tuesday, Sheriff Ian Parkinson announced a new development in the case suggested the remains of Smart could be located in the hillside near the iconic Cal Poly "P" landmark. Smart has been missing since she was last seen while walking to her campus dormitory on May 25, 1996.

Earlier this year, specially trained FBI human remains detection dogs independently identified three separate sites on the hillside as places of interest.

"Once the dogs come out, they go through a very large area out here," said Brenneis. "They're outfitted with GPS collars and there was three spots they showed interest in. Those three spots, we came out, and this the process that we're going through."

The Evidence Response Team is using a combination of heavy machinery and manual labor in their search for the remains. Dirt is first moved using a large excavator and small bulldozer to a site where FBI members can then comb through the material using shovels and rakes.

"We're going through literally each one of the three sites, 20,000 cubic feet of dirt looking for evidence," said Brenneis. "Once we find something, then we'll hone in on it and get down to brushes and trowels and more like an archeological dig."

Brenneis notes technicians are digging three feet deep and moving out to a 90 foot radius. All three search sites are located within a thousand yards of each other on the rugged hillside.

"One of the challenges to this site is the terrain," said Brenneis. "It's very steep and it's very difficult to get to. We spent most of the day yesterday literally just building access, both for the machinery, as well as for the individuals that are doing the digging."

With the project moving tens of thousands of cubic yards of dirt, San Luis Obispo County Sheriff's Office public information officer Tony Cipolla says special attention has been given to the project.

"Before we even began the dig, the Sheriff's Office was in contact with the State Department of Fish and Wildlife to make sure we went through the proper permitting procedures in order to make sure that this dig went according to plan," said Cipolla. "After the dig is done, we'll probably start a remediation effort to make sure we are putting the hillside back to together again."

The FBI has budgeted the excavation project to last until Friday, but notes the schedule is subject to change.

"It is extremely difficult work. It is hard labor," said Brenneis. "We're working shifts of people. We've got 25 ERT members out here running multiple shifts and they'll be working all day and all week until we're done."

Despite working under extremely hot weather conditions on Wednesday, the first few hours of the dig went according to plan.

"It's progressing so far, so good," said Cipolla. We're very pleased with the work that's being done. It's very hot out here, they're working under some backbreaking conditions, so we're very pleased so far with day one."