operating return is incorrectly written and should write it as "operation return" being its meaning:
The return operation is the name given to the police device that is deployed on the roads at the entrance of the cities, after a long weekend, at the beginning of which have left many city vehicles. The device aims, on the one hand to monitor, control and report to the drivers of vehicles; and on the other hand regulate vehicular traffic, which by the mass return of the railcars, it becomes dense and complicated.