Timesheets for employees of Amtrak are riddled with abuse, according to a recent audit report, with cases of workers claiming over 40 hours of work in a single day.

The audit released by Amtrak’s Office of Inspector General (OIG) Thursday found examples of abuse in the overtime system, which totaled nearly $200 million in overtime pay last year.

"[Calendar Year] CY 2014 timesheet data revealed trends and patterns that indicate potential fraud, waste, and abuse in the reporting of overtime and regular time," the audit said. "Some of these trends and patterns may be justified because of the complexity of union agreement rules, the nature of jobs, and the functions employees perform."

"However, our prior investigative work has shown instances in which employees have fraudulently reported hours not worked," the OIG said. "We believe that these trends and patterns merit further analysis and, if appropriate, action by management."

One such trend was employees claiming the impossible feat of working 48 hours in a single day.

"Employees reported 1,357 days in which they worked more than 24 regular and overtime hours," the OIG said. "Ten employees reported working at least 40 hours in a day."

Of those 10 employees, a serving attendant in the Café Car, who earns an average of $23 an hour, recorded 47.95 hours in one day, 31.01 of which were recoded as overtime.

Numerous employees also claimed to work 20-hour days. There were 1,891 timesheets that recorded a range of 22 to 24 hours in a single day, and 7,145 that listed between 20 and 22 hours in one day.

Another troubling finding that likely indicates abuse of Amtrak’s payroll system was the high number of employees claiming overtime. Some employees reported over 74 hours of overtime on top of a normal 40-hour week. Amtrak’s overtime is paid at either 1.5 or 2 times the hourly rate.

One employee, a locomotive technician, claimed to have worked 130 hours in a single week, with 90 hours of overtime on top of 40 hours of regular time. There are 168 hours in a week.

Another train attendant claimed 110.56 hours of overtime in a single week, and no regular hours.

"Some employees repeatedly reported working overtime but no regular hours, including five employees who reported at least five weeks with overtime but no regular hours," the OIG said.

In addition, there were 2,381 timesheets that reported at least 40 overtime hours in addition to 40 regular hours. Eighty-one percent of total hours worked by Amtrak employees in 2014 included at least some overtime hours.

Another area of concern was the number of employees who claimed to work for more than a month straight without a day off. There were 280 occurrences of employees who said they worked at least 31 consecutive days in a row.

A coach cleaner, who is responsible for cleaning the trains and draining and flushing the waste tanks, claimed to work 108 consecutive days.

The union agreements governing Amtrak and its employees are numerous and complicated, a matter alluded to by the OIG. The complexity arises from train employees belonging to different types of unions. Overall, there are 14 unions with 23 different collective bargaining agreements, each with their own rules for calculating employee time and pay.

There are separate unions for "locomotive engineers, onboard service crew members, maintenance of way crews, coach cleaners, and police department employees," the audit said.

Amtrak’s payroll system itself is complicated. "The company uses six timekeeping systems to process timesheets and calculate wage payments," according to the OIG, as well as 179 "unique timekeeping absence and attendance codes."

Amtrak paid roughly 19,300 employees $1.2 billion in 2014, including $199 million in overtime pay. Labor costs account for 29 percent of Amtrak’s annual expenses.

Amtrak did not respond to a request for comment before this story went to press.