At 0856 on 3 August 2016, EPA Region 10 was contacted by the City of Cle Elum Fire Department with a request to provide air monitoring support to a semi-truck tanker/vehicle collision that resulted in a fire. The semi-truck tanker was carrying 4 tanks of varying size of anhydrous ammonia on westtbound Interstate 90. Both eastbound (at MP 84) and westbound lanes (at MP 106) of Interstate 90 were closed and both Indian John Hill rest areas were evacuated due to the fire and hazmat response.
City of Cle Elum Fire Department, Washington State Department of Transportation, and the Washington State Patrol were all on-scene managing the incident.
OSC Zavala along with two START contractors were deployed to the incident. The START contractors conducted air monitoring with ammonia specific instruments. The contractors donned personal protective equipment and SCBA's and placed a temporary plug in the leaking tank. START then reassessed the other tanks and didn't observe any leaks in the 3 other ammonia tanks. The owner of the ammonia tanks arrived on scene later and put a permanant plug in leak.
Once the scene was secure eastbound lanes were reopened and work began on removing the overturned truck and the ammonia tanks. Once the scene was cleared the westbound lanes were reopened.