An early Saturday morning wreck shut down a portion of Interstate 26 for nearly 12 hours and spilled an undetermined amount of gasoline.

The two-vehicle collision took place shortly before 3 a.m. and shut down eastbound traffic from mile marker 187 near Pringletown to mile marker 194 near Jedburg.

A tractor-trailer carrying 8,700 gallons of gasoline hit the rear of a car, and both vehicles went off the road, said S.C. Highway Patrol Senior Trooper Bridget Wyant. The tanker overturned, ruptured its tank and spewed gas, she said.

The driver of the tanker, 26-year-old William Wieters of North Charleston, was taken by EMS to Medical University Hospital, Wyant said. A hospital spokesman said late Saturday he was in serious condition.

Wieters was cited for driving too fast for conditions.

The driver of the car, a 19-year-old Myrtle Beach woman, was not injured, Wyant said.

Officials initially estimated that as much as 4,000 gallons of gas were spilled, but that was an over-estimation, said Jim Beasley, public information director for the S.C. Department of Health and Environmental Control. It will take a few days to determine how much was leaked, but the tanker wasn’t emptied and gas didn’t reach any waterways, he said.

“We believe the environmental impact to be minimal,” he said.

A contractor used vacuums to suck up the oil, and it could take a few days to finish cleaning the area, he said.

Wyant said she didn’t know which company owned the tanker truck; it had too much damage to figure that out.