Emergency crews closed down the Interstate 70 service station east of Lawrence after an unidentified material began burning in a trash can there. The westbound lanes of I-70 were closed while authorities dealt with the issue.
The service area was re-opened shortly after 3 p.m.
Leavenworth Assistant Fire Chief Mike Lingenfelser said the substance - 50 to 100 pounds of a powdery white material in a plastic bag - was found by a worker cleaning the rest stop this morning. The substance was causing the plastic bag to melt; when mixed with water it began to burn.
A hazardous materials crew from Topeka responded to the scene to determine the nature of the powder, but could not immediately make an identification. The material was being packed into steel drums to be transported to another area for further work.
As many as three rest stop workers went to a doctor's office to be checked out; there was no word on their's identities or conditions.
Check back for more details as they become available.