Two tractor-trailers and a pickup collided on Interstate 10 north of Casa Grande on Friday morning, closing traffic in both directions, according to authorities.
An ADOT spokesman said a red Ford pickup was eastbound when one of the tires separated. The driver lost control, crossed the median and struck a semi head-on in the westbound lanes about 9:45 a.m. Another semi rear-ended the first and caused its trailer to roll onto its side and leak formic acid. In all, there were 44,000 pounds of acid in the semi's trailer.
The driver of the Ford pickup is in critical condition at Maricopa Medical Center, as of Friday afternoon.
The drivers of the semis are OK.
The westbound lanes of I-10 remain closed. DPS recommends taking 187 westbound to State Road 87, which turns into Country Club in Chandler. DPS said eastbound lanes could be closed briefly as a result of the hazardous material.
Cook said the road could be closed for a long time as Hazmat crews work to contain the acid and clear it from the roadway. The process could take up to seven hours.
Stay with cbs5az.com and CBS 5 News for updates on this developing story.
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