Two Colorado workers with a Grand Junction specialty-drilling company were killed and a third suffered minor injuries last week in an underground explosion at a dam in Oklahoma. Officials have not released the names of the employees of DA Smith Drilling Co. who died in last Thursdayâs accident at the Robert S. Kerr Dam east of Tulsa. However, a death notice in todayâs Sentinel lists Grand Junction resident Hayden Tucker, 22, a drillers assistant, as having died in Oklahoma on Thursday. The hydroelectric dam creates 12,000-acre Lake Hudson, according to the Grand River Dam Authority, the state agency that finished building it in 1964.