Excavation will begin in about six weeks on the 43,000-square-foot mixed-use project at 8300 Wisconsin Ave. in Bethesda. The site, near Battery Lane, was once home to a Clarion Hotel, but in 2006 Houston developer Patrinely Group unveiled plans for a three-building luxury condominium complex to be called Trillium. Funding fell through and the site was then sold to StonebridgeCarras in March 2011 for $29 million.