BUFFALO, N.Y. (AP) - An industrial plant was fined $12.5 million on Wednesday for illegally releasing the carcinogen benzene into the air and improperly handling hazardous sludge.

The charges followed years of complaints from neighbors about black soot and high cancer rates. A federal judge also ordered Tonawanda Coke to spend up to $12.2 million on health and environment studies in the community.

Company environmental manager Mark Kamholz was expected to be sentenced later Wednesday to as much as three years, five months in prison. He was convicted of obstruction for moving to hide problems from an inspector.

Federal prosecutors had asked for $57 million in fines, saying the company showed "total and utter disregard" for the environment and its neighbors.

But U.S. District Judge William Skretny said he didn't want to impose a "corporate death penalty" and opted for the lower amount to be paid over the course of five years while the company is on probation.

The plant employs 120 people.

Tonawanda Coke CEO Paul Saffrin said his company regrets the mistakes it made and promised not to repeat them.

About 20 civil lawsuits involving more than 250 people are pending.