Missoula, MT -

A Bitterroot Valley asphalt company owner has denied charges his company violated federal safety standards in the September 2012 death of an employee.

The U.S. Attorney's Office says MR Asphalt Inc.'s registered agent and president, Martin Romano of Victor, pleaded not guilty Tuesday to 16 federal violations during a hearing before U.S. Magistrate Judge Jeremiah Lynch in Missoula.

Romano and his company were charged after 54-year-old William Irby Jr. or Corvallis slipped off an oil tank while taking measurements and fell 15 feet, hitting his head on a concrete pad.

Prosecutors say if convicted, Romano faces up to 6 months in prison and a $10,000 fine while the company faces up to $500,000 in fines.