The government filed an $8.23 million suit against E.I. du Pont de Nemours & Co., accusing the chemicals giant of helping produce gasoline containing too much lead at a New Jersey refinery from 1983 through 1985.

The company, a major supplier of lead compounds, said the suit was "without merit" because it was not subject to the regulations it is accused of violating.The Environmental Protection Agency said a complaint, filed Wednesday in U.S. District Court in Newark, N.J., charged that a joint venture of du Pont and three other companies put 2 billion grams too much lead - 2,200 tons - in gasoline blended at Carteret, N.J.

The government seeks the maximum fine of $10,000 a day for each of the 823 days specified in the complaint.

EPA in 1986 filed an administrative complaint against du Pont but was unable to reach a settlement with the company.

In Wilmington, Del., company spokesman Tom Barry read a statement from Jerry McCleskey, planning director of the company's chemicals and pigments department, charging that EPA's action was "without merit."

"The allegations are false. We will contest the novel and strained interpretation of the regulations. We complied fully with all regulations applicable to lead suppliers," and cannot be held responsible for alleged violations by others, McCleskey's statement said.

Later, Barry himself said it was "simply not a fact" that the operation was a "joint venture" as EPA said.

Du Pont said it was only a supplier. But EPA contended that du Pont decided how much lead was to be used, injected the compound at the blending plant, determined that the final product was suitable for sale as leaded gasoline and advised the other participants in the venture about EPA regulations.

The activities in effect made du Pont a refiner, subject to the refining regulations and just as responsible for the excess lead as any of the other parties, EPA said.

The agency filed administrative complaints against the other three companies, two of which are now inactive.