A man convicted of dumping toxic chemicals into Louisville's sewer system was sentenced in federal court Friday to two years in prison and fined $50,000.

Donald Distler, president of Kentucky Liquid Recycling Inc. of New Albany, Ind., was convicted in December of discharging pollutants into the Ohio River in March 1977 and of causing Louisville's main sewage treatment plant to be knocked out of operation.

The Distler case was the first in which the federal government had brought criminal charges for pollution of a waterway, officials said.

U.S. District Judge Charles M. Allen imposed the maximum sentence, citing "callous disregard" for public safety on Distler's part, and denied a request for probation for Distler.

Distler's attorney, Frank Haddad, said the case would be appealed. Distler had been free on bond pending sentencing and remains free on bond pending appeal.

Local, state and federal governments spent over $3 million on cleaning up the treatment plant and sewer lines and investigating the case.

U.S. Environmental Protection Agency technicians who said traces of chemicals found in the sewer matched samples taken from the Kentucky Liquid Recycling storage yard in New Albany.

A year-long cleanup of the affected sewer was completed last week.

Workers had scraped some 800,000 pounds of contaminated sludge from more than three miles of sewer line.

The chemicals -- hexachlorocyclopentadiene and octachlorocyclopentene, known as "hexa" and "octa" -- are solvents used in industrial processes such as the manufacture of flame retardants and pesticides. They were dumped down a manhole over the city's largest sewer main.

For 30 months after the discovery of the dumping, untreated sewage was diverted from the affected line directly into the Ohio River, at a rate estimated at 6 million to 10 million gallons a day.

The contamination was discovered after 34 workers at the city's main sewage treatment plant complained of symptoms including headaches, nausea and dizziness.

For months after the chemicals were discovered, the Louisville Metropolitan Sewer District searched for a private firm willing to take on the cleanup job, but none could be found. The utility was forced to develop its own cleanup strategy to take care of what MSD spokesman John Tierney called "the biggest and worst spill of its kind."

During the past year, 14 MSD workers have spent about 2,200 hours apiece scraping the chemicals out of the sewer lines.

They had to dress in throwaway coveralls, rubber boots and gloves, sealed at all seams with tape. They wore respirators and breathed through lines hooked to an air-supply pump above ground.

Weekly blood and urine samples were taken from each member of the crew, and sent by airplane to the University of New Orleans, where they were analyzed for traces of the chemicals.

No contamination was found, and during the cleanup no time was lost to on-the-job injuries.

The workers, all volunteers for the assignment, received extra pay for hazardous duty. At times they faced sewer temperatures as high as 120 degrees Fahrenheit.