The Virginia State Water Control Board voted yesterday to seek legal action against the industrial city of Hopewell for polluting the James River with its recently opened regional sewage treatment plant.

The action came after latest figures showed that the plant, which opened last year as a replacement for the old facility that was knocked out of service by contamination with the pesticide Kepone, is far exceeding its pollution limits.

Gov. John N. Dalton, at dedication ceremonies in Hopewell in September, praised the $48 million plant and the regional efforts that got it built. He did not know at the time, his staff said later, that even as he spoke, the plant was violating its discharge permit.

Hopewell, a center of chemical and pulp industries about 30 miles south of Richmond on the James River, had succeeded earlier this year in heading off tough action by the water board by promising to hasten repairs and make other improvements. The board at that time granted the city extensions despite a recommendation by its staff that legal action be recommended.

Yesterday's action -- a request that Virginia's attorney general file suit against the city -- came on a 7-to-0 vote after the board met in executive session.

The attorney general's office said it would report to the water board on Dec. 19 whether the suit - which could result in fines and other penalties - will be filed in state or federal court.