An investigation is underway into the death on Tuesday afternoon of a Norridgewock man at an Old Town pulp mill.

The federal Occupational Safety and Health Administration and local police are investigating the death, which occurred at the Expera Specialty Solutions mill. Old Town police Capt. Lee Miller identified the victim as Mark Guay, 54.

Police think Guay was trying to prepare his chip trailer to be unloaded and had climbed up onto his trailer, then lost his balance and fell about 25 feet to the bottom of a chip machine’s hopper, Miller said. Guay was working as a truck driver for Richard Carrier Trucking, of Skowhegan.

A company spokeswoman also said the victim, pronounced dead at the scene, was a contractor, not an employee.

The formerly closed mill reopened earlier this year after Expera Specialty Solutions of Kaukauna, Wisconsin, bought it.