Donald Everett Martin Jr. was driving a Kenworth tri-axle dump truck filled with gravel, when something went wrong. Authorities are still unsure what caused him to strike a guardrail, go airborne and land on the railroad tracks below.
Witnesses told responding officers Martin was all over the road prior to the crash.
"We are still gathering information," said Deputy Adam Hull of the Putnam County Sheriff's Department.
Hull, who was the first law enforcement officer to arrive on the scene, said the sheriff's department is awaiting Martin's autopsy and an inspection of the vehicle.
Those two items are the only keys to figuring out what happened, he added.
There is some mystery surrounding where Martin resided. A Texas address appeared on his driver's license, but it is speculated Martin was from Illinois.
Following the accident, one eastbound lane of I-70 was closed for a short time while crews worked to clean up the scene.
Cloverdale Fire Department, Operation Life and Indiana State Police all responded to the accident. Curtis Wrecker Service worked to recover the demolished dump truck from the railroad tracks.