UNDATED (CNN) -- A new report blasts Amtrak for dangerously overlooking drug and alcohol use by its employees.
An internal audit by the nation's largest passenger rail carrier, says drug and alcohol use by Amtrak's employees has steadily risen since 2006.
The majority of employees who failed drug tests were reported to have tested positive for cocaine and marijuana.
The report says Amtrak's employees failed drug and alcohol tests at a staggering 51-percent higher rate than the rail industry average.
Federal regulations requiring railroad companies to do drug and alcohol testing were implemented following a deadly 1987 Amtrak collision in Maryland.
In that accident, investigators concluded that a Conrail freight train engineer was under the influence of marijuana and ran three signals before colliding with the passenger train. Sixteen people were killed.