A garbage collector who was seen shovelling snow into his truck while also picking up waste was apparently not performing a good deed.

Anna O'Sullivan of Milton, Ont., posted video to Facebook on Monday of what she thought was a nice gesture. The 30-second clip shows an employee of Miller Waste Systems shovelling snow from the front of her house.

"Along with picking up the usual bag of garbage, they also picked up the excess snow that was beside the curb," O'Sullivan wrote, adding the hashtag #ilovemilton.

But the conversation online soon turned to allegations that the worker was padding the weight of his truck, because Miller is paid by the tonnage of the waste it collects.

The Halton Region government launched an investigation.

If they dump it on the floor and it's full of snow … we know that trick. — Jim Harnum , commissioner of public works for Halton Region

Jim Harnum, commissioner of public works for Halton Region, told CBC News officials "knew exactly" what the worker was doing once they saw the video.

The region is "not paying for anything that truck did that particular day," he said.

The company is also facing a fine or damages, he added.

Harnum said the region has a good relationship with Miller, whose contract is worth some $13 million a year. It has collected garbage there since 2008.

He said what happened in Milton appears to be an isolated incident, adding that the garbage collection system is designed to spot cheating. Collection is monitored on the street by supervisors and checked by spotters once it's dropped off at transfer stations, he said.

Jim Harnum, commissioner of public works for Halton Region, says the garbage collection system is designed to spot cheating. (CBC)

"If they dump it on the floor and it's full of snow, or if it's soaking wet — we know that trick and we would reject the load," he said.

"We haven't seen that … so we think this is an isolated incident."

He said officials are also checking that truck's records for the last two years for any "anomalies."

Milton Mayor Gordon Krantz, who sits on the Halton regional council, said the matter should be discussed at the next council meeting, but added that Miller "has done an outstanding job" with its contract.

"There needs to be a little homework done on this," he said. "The taxpayers of Halton deserve it."

Halton Region recently renewed its contract with Miller for another eight years. The company has not responded to interview requests.