New Orleans officials have no way of telling who is buying gas on City Hall’s dime and should tighten up oversight to prevent fraud, according to a report released Wednesday by city Inspector General Ed Quatrevaux.

Quatrevaux’s office said it examined six years of data from the city’s $3.2 million-a-year fuel program. It found that employees with city-owned vehicles often shared city-provided gas cards and the PINs associated with those cards in violation of city policy.

Employees in almost three dozen city departments use city-owned vehicles and fuel. They are supposed to enter their vehicle’s odometer reading every time they fuel up at a city-owned gas station. That way supervisors can track how much the vehicles are being used.

Quatrevaux’s office turned up some suspect odometer readings and found that officials did not consistently deactivate cards that belonged to former employees.

At the city’s main gas station on Broad Street, investigators actually found PIN numbers scrawled on a sign attached to a fuel pump.

They also identified several active PINs assigned to people no longer employed by the Police Department, and they cited odometer mileage entries that were highly unlikely, such as 5 or 22,222.

On a single day in September, one fuel card assigned to the NOPD was used nine times, with three transactions occurring in a single minute.

“The city needs a complete overhaul of its fuel dispensing program to safeguard tax dollars,” Quatrevaux said. “That includes consequences for those who abuse or fail to enforce policies.”

Deputy Mayor and Chief Administrative Officer Andy Kopplin agreed with Quatrevaux’s findings and said employees would be disciplined for abusing the program.

Kopplin said that by 2017, the city will deactivate and reissue all current fuel cards and PINs and place limits on how much gas can be pumped at a time.

He also said the city will start requiring employees to provide accurate mileage numbers, will train managers to spot inaccuracies and will tighten up monitoring at non-automated gas stations.

Kopplin also said the city will deactivate PINs when workers retire or leave the city payroll for other jobs.

Kopplin will leave his post in mid-August to become the CEO of the Greater New Orleans Foundation.

Follow Jessica Williams on Twitter, @jwilliamsNOLA​