The owner of Blackhawk Plaza in Danville is in default on two loans totaling a combined $31 million that were provided to the property by Preferred Bank, according to documents filed on Jan. 30 with the Contra Costa County Recorder's Office. These new delinquencies are separate from $5 million in financing that Nano Banc provided to the owner of the property, whose addresses include 3380 Blackhawk Plaza Circle, county real estate files show.