The Allegheny County Health Department yesterday ordered Shenango Inc. to cut back production at its Neville Island coke plant to reduce emissions, but by a lesser amount than the department had ordered last month.

Guillermo Cole, department spokesman, said the revised order was a result of continuing negotiations with the company regarding repair of its coke ovens. He added that health officials expect to reach an agreement with company officials later this week that would set a timetable for repairs.

The order that took effect yesterday requires Shenango to lengthen its normal 18-hour coking times to 20 hours. That reduces the number of times that cooked, hot coke is removed from each oven, an operation that can release noxious gases.

Cole acknowledged that the revised order is not as stringent as last month's, which would have increased coking times to 24 hours. But he also noted that the company has shut down five of its 56 coke ovens for repairs.

The changes in coking times and the closed ovens should combine to reduce emissions by 19 percent, he added.

Negotiations continue with the company on a consent agreement, Cole said. As now envisioned, that agreement will include a listing of all the defective ovens and a timetable for repairing them.

"I think we're on the verge of an agreement with them," Cole said, adding that he expects an announcement later this week.

"I certainly don't see any reason for the Health Department to let up on Shenango," said Myron Arnowitt of the environmental group Clean Water Action. He said members of the group saw no decrease in visible emissions from the plant last month.

A company official did not return a call requesting comment.

The department also has fined Shenango $252,000 for exceeding county and federal emissions standards. The company has appealed that fine. Cole said a settlement of that appeal likely will be included in the consent agreement now in the works.