(CN) - Suffolk County, N.Y., may have violated federal law by spraying mosquito pesticides over creeks, the 2nd Circuit ruled. The court largely overturned a ruling upholding the county's spraying practices, adopted to combat mosquito-borne disease.
In 1993, the county had its first instance of mosquito-borne disease in 75 years. There have since been four reported deaths due to mosquito-transmitted diseases such as West Nile Virus, malaria and encephalitis.
Suffolk County tried to reduce the health risks by spraying mist pesticides from trucks and helicopters. Although highly toxic to fish, the pesticides were approved by the Environmental Protection Agency.
Peconic Baykeeper, Kevin McAllister and Alfred Chiofolo filed a citizens' lawsuit in federal court, claiming the county violated the Clean Water Act by ignoring the pesticides' label barring "direct application over lakes, ponds and streams" or "areas where surface water is present."
After a six-week trial, U.S. District Judge Arthur Spatt ruled that the spraying fully complied with federal law, despite evidence that the county sprayed over creeks. He refused to block the county from further spraying.
The Manhattan-based appeals court vacated, saying the lower court "did not explain the basis for its conclusion that all spraying was in compliance with FINRA (Federal Insecticide, Fungicide and Rodenticide Act)."
The 2nd Circuit also disagreed with Judge Spatt's finding that the trucks and helicopters were not "point sources" under the Clean Water Act.
"Here, the spray apparatus was attached to trucks and helicopters, and was the source of the discharge," U.S. District Judge Kevin Castel wrote for the three-judge panel.
But the court upheld the county's dredging of mosquito ditches. It agreed with Spatt that the ditches were "drainage ditches," not new mosquito ditches, and did not require permits.
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