Chapman had asked drivers to use W.Va. 62 to get from Putnam County to Mason County.
Road crews set up three roadblocks and turned people away about four miles from the incident. The crews were told not to let anyone through the roadblocks until areas could be checked for the chemical.
Mike Dorsey, homeland security and emergency response chief at the state Department of Environmental Protection, said the initial call about the incident reported incorrectly that it involved hydrogen sulfide, a rotten-egg-smelling chemical that is highly poisonous, corrosive, flammable and explosive.
Dorsey said investigators quickly discovered that the truck owned by Bridge Terminal Transport of Charlotte, N.C., was carrying 80 55-gallon drums of glutaraldehyde.
The West Virginia Department of Transportation said rain hindered cleanup efforts and officials were concerned that water might turn the chemical into a gas. It was not clear Friday night if that occurred.
"There was about a 1-foot-wide stream of stuff coming out of the back of the truck," Dorsey said.
Still, the Putnam emergency dispatcher said Friday night he was unsure how much of the chemical was spilled.
Staff writer Ken Ward Jr. contributed to this report.
Reach Travis Crum at travis.c...@wvgazette.com or 304-348-5163.