Owners of a Centerville steel plant pleaded guilty Thursday to violations of the Clean Water Act after pumping pollutants into the South Davis County sewer system.

Federal prosecutors are calling the case the "largest federal criminal (environmental) penalty to date in Utah."Syro Inc., an Ohio-based corporation that owned and operated the steel products manufacturing facility, agreed to pay more than $1 million in fines and voluntary contributions.

The plea agreement settles a case filed by the U.S. Attorney's Office in Utah earlier this year, charging Syro with discharging waste waters from tanks containing zinc, a toxic pollutant, and polluting levels of pH.

In statements made before U.S. District Court Judge Dale Kimball, prosecutors said that Syro pumped contents of a rinse tank into the facility's floor drain, which feeds into the South Davis County Sewer Improvement District lines. The dumping had occurred for 20 years prior to the purchase of the Syro subsidiary by the Dallas-based Trinity Industries Inc., in 1992, according to court documents filed in March.

When the new owners learned of the dumping practices, they "responded to the problems and told workers to stop dumping," prosecutors told Kimball. The owners also filled the drain with concrete and replaced ground pipes that may have had zinc sediment.

"I am very pleased with the work of our attorneys, the U.S. attorneys, and all of the investigating agencies in prosecuting Syro," said Utah Attorney General Jan Graham. "We are serious about protecting our state, serious about investigating these crimes and serious about enforcing . . . no matter how difficult they may be."

U.S. Attorney David Schwendiman said this was the first time agents from the Environmental Protection Agency who are stationed in Utah have investigated this type of case. Agents have only been in Utah full time for six months.

Schwendiman said the criminal charges and the fine imposed on Syro should send a strong message to individuals and businesses in Utah that environmental violations that endanger public health won't be tolerated.

"We've demonstrated in this case that we have what it takes to go after those who endanger the public safety by committing environmental crimes. We have the resources and tools available - which we'll use - to pursue these crimes," he said.

As part of the agreement, Syro will make voluntary contributions of $100,000 to both the Utah Department of Environmental Quality's Hazardous Substances Mitigation Fund and the South Davis County Sewer Improvement District, and $50,000 to the Western States Project for training investigators in environmental enforcement. A victim assessment fee of $800 was also added by Kimball.

Dal Waymant, general manager of the South Davis Sewer Improvement District, said the money he received in the agreement will go toward a feasibility study for the construction of additional wetlands near the Farmington Bird Refuge.

Waymant said that although no wildlife within the refuge was affected by the waste dumping, individuals and businesses need to think twice before dumping anything into the sewer system.

"This should be a warning shot to every industry not to dump things down the sewer without checking with the sewer district first," Waymant said.

Syro Inc., formerly known as Syro Steel Company, manufactures and galvanizes guard rails and other steel products at a plant in an industrial area west of I-15 at 950 West, 400 South in Centerville.