NEW YORK (CBSNewYork) – One man has found an interesting way to pick up a few extra bucks, while even helping to save the environment – and you could cash in, too.

CBSN New York’s Natalie Duddridge spent the morning the documenting trucks and buses idling on city streets

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She also tagged along the with an Upper West Side resident who is now making money off of a little known traffic law.

Meet George Pakenham, mortgage broker by day, engine exhaust vigilante by early morning and night.

He has spent years letting drivers know the city’ law against idling that says you must turn your engine off within three minutes in the five boroughs. That time drops to one minute in a school zone…

Pakenham even made a documentary about his environmental activism called “Idle Threat.”

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In 2017 the city passed a law allowing citizens to submit photo or video evidence of drivers idling to the Department of Environmental Protection.

If a ticket is issues to a driver – a fine averaging $350 – the citizen who submitted it gets to collect 25 percent, or on average $88.

In the last few years, Pakenham has made thousands.

“I’ve made about $10,000 cash in my bank,” he said. “You provide video and photographic evidence, then you create an air complaint form that you fill out and submit that electronically to the DEP and then you have to wait.”

Friday morning, CBS2 found several drivers idling, including one for nearly 20 minutes. When approached about it, the driver said “I know it’s wrong, I don’t know why I do it. Maybe it’s out of habit.”

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Such idling happens despite large signs hanging in the neighborhood noting no engine idling, with a maximum fine of $2,000.