UPDATED 9:32 p.m.: The Virginia Department of Transportation says it has cleared the scene of a big rig crash in Botetourt County. Backups are still at about 1 mile, but are expected to ease up soon.

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UPDATED 9:20 p.m.: The Virginia Department of Transportation is now reporting that traffic congestion related to this morning's tractor-trailer crashes is easing up. Backups in both directions are now down to about 1 mile. One lane of each side of the Interstate is now open.

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UPDATED 8:02 p.m.: Traffic backups are about four miles.

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UPDATED 5:47 p.m.: NEWS7's Justin McLeod reports that the southbound lanes of Interstate 81 are closed again to make way for a wrecker.

Traffic is backed up 11 miles southbound, and 5 miles northbound.

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UPDATED 4:30 p.m.: VDOT tells NEWS7 it will be about three or four hours before all lanes are back open.

Crews still have to upright a second trailer.

There is about a six mile backup northbound and southbound.

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UPDATED 4:11 p.m.: Traffic backups are about 6 miles, according to VDOT. Southbound congestion is about 10 miles.

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UPDATED 3:22 p.m.: The right northbound lane and the right southbound lane of Interstate 81 in Botetourt County near mile marker 167.8 are now back open.

There are still major traffic backups.

As of 3:15 p.m., traffic was backed up southbound by about 10 miles, and northbound traffic was backed up 8 miles.

The backups and delays are because of a crash involving two tractor-trailers.

One of the tractor-trailers was carrying a poisonous chemical called Thioglycol.

(LEARN MORE ABOUT THIOGLYCOL AND ITS IMPACTS)

One of the truck drivers was killed in the accident.  State Police say he is 51-year-old Wayne Richie Kratzer of Mifflintown, Pennsylvania.

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UPDATED 3:10 p.m.: One lane of traffic in each direction on Interstate 81 in Botetourt County have been reopened.

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UPDATED 2:38 p.m.: Traffic backups are between 8 and 9 miles.

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