(Radio Iowa) – The Iowa Department of Natural Resources is investigating after the contents of a semi-trailer were spilled in a fire at the I-80 eastbound rest area near Adair Tuesday. The D-N-R says the semi owned by World Way Freight Transport was hauling poly totes of lactic acid when the driver noticed the trailer tires were smoking and pulled over at the rest area. D-N-R Environmental specialist Alison Manz says they realized the environmental problem after the fire was out.

The majority of the trailer and its contents were on-fire by the time firefighters arrived. It is estimated that approximately 550 gallons of lactic acid were lost. The acid and water used to fight the fire flowed through two storm drains and into tile intake that runs into an unnamed tributary of the South Fork Middle River. No dead fish were found as of Wednesday. Manz says private crew is cleaning up.

Manz says the landowner moved his cattle offsite and recommends anyone downstream to do the same. The rest area will remain closed until clean-up is complete. Contaminated soil will be excavated or treated on-site.