Environmental attorneys say a federal lawsuit filed Wednesday afternoon in U.S. District Court for the District of Connecticut against a well-known school bus company can have legs if the plaintiffs play their cards right.

Boston-based environmental nonprofit Conservation Law Foundation filed the suit after it said its investigators found drivers for New Britain-based DATTCO Inc. had left their buses idling for more than the three-minute maximum under state and federal law 132 times in October, November and earlier this month in numerous communities in Connecticut.

Officials from CLF said the alleged violations were observed and video-recorded and environmental attorney Mark Zimmerman said that could be enough to prove their case, if the nonprofit will do its homework.

"They will have to prove the overidling caused a fair amount of pollution," said Zimmerman, a shareholder with the Hartford offices of Updike, Kelly & Spellacy. "It's not impossible. You'd have to get experts who will testify to the emissions levels and what the contaminants would be. One bus idling too long is not a big deal, but multiply that by many vehicles and the accumulation of buses and it can be a real environmental issue."

As of Thursday afternoon, no attorney had filed an appearance for DATTCO.

In an emailed statement Thursday, the company wrote that it "has a long history of compliance with Connecticut's idling regulations and has never been cited by the Connecticut Department of Energy and Environmental Protection or the Connecticut Department of Motor Vehicles for any violation of these regulations."

"As members of many communities located throughout the state, DATTCO employees have a strong and vested interest in maintaining a healthy environment," it wrote.

But plaintiffs counsel Kenta Tsuda, a staff attorney for CLF, said Thursday that both state law and the federal Clean Air Act are on his side.

"This lawsuit should show others that those who want to protect the environment can do so when we use our federal environmental laws in federal court," Tsuda said.

Under Connecticut law, vehicles cannot idle for more than three minutes, with exceptions that include being stuck in traffic, Tsuda said. Connecticut instituted a State Implementation Plan that was approved federally via the Clean Air Act, so Tsuda argues the three-minute idling ruling is in violation of both Connecticut and federal law. Each state is required to develop a State Implementation Plan to achieve federally-set air standards, which can include rules related to the idling of vehicles.

Investigators from the nonprofit found the school buses idling from four minutes and longer and, in one case, up to 41 minutes.

"The big takeaway is that this is a case addressing an extremely important environmental issue," Tsuda said. "And that is exhaust pollution from idling vehicles. For school buses to expose children to fine particulate matter, nitrogen oxide, sulfur dioxide, benzene, formaldehyde and other pollutants is objectively crazy and wrong."

Tsuda said his group targeted DATTCO because "of the risks its illegal pollution poses to surrounding communities." He said the foundation has filed four similar lawsuits in the past year in Massachusetts. Those cases are pending.

"These cases stem from our new tailpipe-pollution campaign," Tsuda said. "Pollution of this type is extremely dangerous, especially for children and the elderly."

According to the lawsuit, "These pollutants enter the lungs, impairing respiratory and cardiovascular health." It claims children are particularly vulnerable because of their developing lungs.

Tsuda said he is optimistic of prevailing because "the law is pretty clear-cut."

Zimmerman said idling, especially in New England, is prevalent because in colder states motorists tend to let their vehicles warm up longer.