Tension rose today in the 5 1/2-month standoff between striking union miners and the A.T. Massey Coal Co. as a truck carrying nonunion coal to a processing plant hit a car carrying four strikers, slightly injuring them.

More than 1,000 pickets at a time, some wearing masks and armed with clubs and rocks, have attempted this week to stop the flow of coal by rail into and out of the processing plant.

But Massey appears to be winning the bitter confrontation.

Late today, state police helped the Norfolk and Western Railroad remove three pickup trucks from the tracks, allowing an 80-car freight train loaded with 8,500 tons of coal to leave Massey's struck Sprouse Creek processing plant.

Todd Kiscaden, a Massey employe, said the coal was being shipped to the Ford Motor Co.'s Rouge steel plant in Michigan. Kiscaden said it was the third trainload of coal to be shipped out since the strike by the United Mine Workers of America began last October when Massey refused to sign the national coal contract.

Pickets sat and stood in the path of the train, a tactic that turned back two trains earlier this week. Today the train merely slowed.

The most seriously injured person today was William Barman Davis, 27, of Naugatuck, who suffered a back sprain. Davis said he and three other miners in a compact car were on their way to lunch when one coal truck passed them and another came up quickly from behind.

"They sandwiched us," he said from his bed at Williamson Memorial Hospital. The car went into a ditch after being struck from behind.

Massey official Don Blankenship said the truck driver was trying to pass the car and brushed it. "He didn't even know he struck it," Blankenship said.

On Thursday, strikers stoned a convoy of coal trucks en route to the processing plant and the truckers retaliated by smashing into 10 cars and trucks that pickets had used to form a serpentine blockade along the highway. After the convoy got through, the strikers overturned a company vehicle and burned it on the railroad track.

Ricky Starr, 25, who drove one of the trucks in the convoy, said, "I don't feel I've taken anyone's job. I was laid off for a year before Massey hired me. They the strikers had a chance to work."

Donnie Hurley, 35, added, "No one should have the ability to deprive me of a right to work." Hurley, who said rocks have been thrown at his house, added that he did not blame the driver who rammed the cars in the blockade. "You're scared when you're out there driving and see rocks coming at your head," he said.

Company president E. Morgan Massey tonight said the strikers' roadblocks have resulted in eight people being dragged from their cars and "viciously assaulted by thugs drawing checks from UMWA headquarters."

Each side has accused the other of escalating the violence, and both criticize the state police as failing to enforce the law, preferring to stand by until a major incident occurs.

State Police Capt. R.G. Fink said officers received conflicting stories about today's incident, but he said he expected that the driver of the coal truck that hit the car would be arrested. Fink noted that police have arrested more than 300 people on both sides since the strike began.

Everywhere along the scarred hillsides are signs, literal and figurative, that both sides are prepared for a long siege.

The picket signs, which just last month had a homemade flavor, have become billboards, pledging "We won't be held hostage," and "Solidarity" and "This isn't Poland or South Africa."

The top-of-the-table issue here is job security, but the underlying question is the future of the union.

Richmond-based Massey, a subsidiary of Royal Dutch Shell, wants to sign individual contracts with the union for its various subsidiaries. The union wants a single contract for all Massey operations. Without that, the union argues, Massey can shut down a mine, reopen under a new name and hire nonunion workers. With a uniform contract, the company would be required to offer jobs to miners laid off at its other facilities, before hiring outside workers.