Union Drilling (UDRL) said J. Michael Poole quit his job as executive vice president, operations, for personal reasons.
The Fort Worth, Texas, contract driller said CEO Christopher Strong will take over Poole's duties on an interim basis. Union is searching for a replacement.
"Mike has been a valuable member of the Union Drilling team since 1997, helping shape the company into what it is today. We are sad to see him go and we wish him well," said Strong. "Looking ahead, I am pleased to have this opportunity to directly oversee our continued growth on the operations side until we find a suitable replacement."