HILL AIR FORCE BASE — After a new five-story building opened here on Monday, state and federal officials say the west side of Hill Air Force Base should be bustling with activity for years to come. Hill officials opened a new 75,000-square-foot office building that will house military and civilian workers, as well as several defense contractors. The new building is the newest piece of the Falcon Hill National Aerospace Research Park development, an Air Force Enhanced Use Lease program that allows private entities to lease underused military land.

David Williamsen, chief of the EUL Program Office at Hill, said plans are in the works for the staff from the Air Force Nuclear Weapons Center’s Intercontinental Ballistic Missile Systems Directorate to occupy one floor of the new building, while defense contractors are in negotiations with the developer to occupy the other two floors.

The new building is the fourth major construction project completed in Falcon Hill by developer Sunset Ridge, a development partnership between Woodbury Corporation and Hunt Development. Air Force officials say Falcon Hill will bring additional jobs and revitalized infrastructure that also includes new roads and utilities in addition to new buildings.

“We’ve invested $75 million in the project so far,” said Jeff Woodbury, with the Woodbury Corporation. “But this is really only the beginning. We’re gaining a lot of velocity and there are companies doing business at Hill right now that want to be part of this project. We want to (build a new building) at least once a year.”

So far the development has seen the construction of the ICBM Prime Integration office building just inside the West Gate in March 2012, followed by a new 35,000 square-foot building for the 75th Security Forces Squadron in January 2012. The base constructed a new West Gate in April 2012 and moved it further east to improve traffic safety on Interstate 15 and accommodate plans for additional Falcon Hill construction outside the gates.

Williamsen said Sunset Ridge is in the process of constructing a new 10,000-square-foot commercial retail facility outside the West Gate to support the project.

While declining to offer specifics, Williamsen and Woodbury said there are hundreds of potential projects in negotiations both inside and immediately outside Hill security gates.

“I’ve been told to keep quiet because a lot of these companies want to make the announcements themselves,” Williamsen said of incoming retail tenants. “But I can kind of keep it on the sly and say you’ll probably see some announcements in the next 30 days or so.”

At the same time the doors opened on the new facility, demolition work began on a building just across the street. The Falcon Hill plan calls for demolition on a series of World War II-era buildings that have been used as overflow office space along the west side of the base for years. Demolition on the first of those buildings to come down, which had been occupied by the base’s Security Forces Squadron, began Monday.

“What was adequate 40 years ago isn’t adequate today,” Williamsen said. “And these buildings were never meant to be office buildings.”