Nurses at three Prince George's County medical facilities remained on the job yesterday past a strike deadline as the corporation that operates the facilities made a new contract offer.

Chief union negotiator Larry Grosser said late last night that the offer will be presented to the nurses for a vote this weekend, and if it is rejected a strike will begin at 7 a.m. Monday. He said union negotiators are recommending rejection.

The nurses had threatened to strike at 3:30 p.m., the end of yesterday's day shift, if a settlement were not reached. But there was no work stoppage, and negotiations between the nurses union and the corporation continued until they were broken off late in the evening.

According to a statement issued jointly by both union and management last night, both sides agreed on a 35-cents-an-hour across-the-board increase retroactive to Aug. 14. The corporation offered an additional 35-cents-an-hour increase effective next July 1, but the union called for the second increase to be determined through a form of arbitration. The nurses' current pay is estimated at $9 an hour.

The corporation's offer was unsatisfactory to the union bargainers in the areas of wages, the mechanism of grievance procedures, the amount of pay union officers would receive while on union business and a requirement that all nurses pay either dues or a fee to the union.

The contract between the union and the Community Hospital and Health Care System Inc., which recently took over management of the county-owned Prince George's General and Greater Laurel-Beltsville hospitals and Bowie Health Center, has been in dispute for eight months.

The 650 registered nurses at the three facilities had initially asked for an 11.5 percent salary increase this year and the hospital corporation had offered 3.3 percent. The corporation also proposed eliminating annual step increases and replacing them with discretionary merit raises.

Unable to resolve the differences, the union membership met 10 days ago and voted to strike when the shift change occurred yesterday.

With the strike deadline hanging over them, negotiators for the two sides met early yesterday in a sequestered conference room on the grounds of Prince George's General Hospital in Cheverly. Negotiations continued until 1:30 p.m., when hospital corporation representatives left to consider a new offer by the union, the local chapter of the Maryland Nurses Association.

At 3:30 p.m., when the strike was supposed to have begun, the day shift at the hospital left and the night shift went to work without incident. Hospital officials earlier this week had said that they were prepared for a strike and had arranged for alternative staffing if one occurred.

Two hours after the strike deadline the two sides reconvened and soon after a short burst of applause could be heard in the closed conference room.

Nurses at Prince George's General were reluctant to discuss the contract dispute yesterday. Two nurses who had just completed the day shift said that a strike vote had not been taken earlier in the day, as union leaders had promised would happen if the strike was to begin as planned.

One nurse, who declined to be named, said, "We can't strike until we get management's last and final offer." Both the nurses said that they had been besieged by questions all day long from curious doctors and other hospital personnel, many of whom would have to work extra shifts if the nurses walked out.

"The patients were really upset also," one of the nurses said.

According to union President Carolyn Larkin, the nurses in the union are paid between $17,300 and $23,300, generally less than other area nurses are paid, Larkin said. Mary Carlson, executive secretary of the D.C. Nurses Association, said nurses in the District and nearby suburbs generally receive between $19,000 and $30,000.

One Prince George's nurse said yesterday that "money is important, but what we really need is more help." She said nurses often are overworked to the point where their jobs are no longer enjoyable.