PORTSMOUTH (AP) - State environmental regulators have asked a judge to fine or jail owners of a closed coal-processing plant to get them to follow a court order issued four months ago to cleanup chemicals and other waste.

State officials on Tuesday asked Scioto County Common Pleas Judge Howard Harcha to find the New Boston Coke Corp. in contempt of court. The Ohio Environmental Protection Agency asked the judge to impose fines of $250 a day for each violation and to sentence company executives to jail if necessary.

Harcha in December ordered New Boston Coke to pay $2.6 million to the Ohio Environmental Protection Agency for damaging the environment and threatening public health. The EPA said an elevated cancer risk existed when the plant was operating.

As part of that judgment, the company also was to clean up the site.

''There were a number of things they were supposed to do,'' said Mark Gribben, a spokesman for Attorney General Jim Petro. ''They've failed to complete any of them.''

Harcha has scheduled an April 30 hearing.

New Boston Coke, based in Troy, Mich., plans to file a written response later this week, said Paul Astolfi, a Detroit lawyer representing the company. Astolfi declined Wednesday to discuss the case further.

The plant closed in April 2002, ending 86 years of operation along the Ohio River about 85 miles south of Columbus.

It baked coal into hotter-burning coke, which fuels furnaces in steel mills. Plant officials filed for bankruptcy protection in July, six months before the court judgment.

Tests had determined air quality near the plant was worse than in the largest industrial areas in the United States.

After closing the plant, the company left behind hundreds of thousands of gallons of chemicals, storage tanks, waste piles and tar bins. New Boston Coke's cleanup plan had been rejected earlier this year, and the state hasn't heard from the company since March 3.

''They just kind of dropped it,'' Gribben said.

The company hasn't paid the $2.6 million judgment against it. A federal bankruptcy court in Michigan is sorting through the claims of creditors and overseeing distribution of company assets.

Ohio officials said that although they might never get the money, they will push to ensure that dangerous materials are removed from the property.