The driver of an asphalt truck was killed when it rolled at the bottom of Floyd Hill, exiting Interstate 70 Thursday morning.As a result of the crash, the ramp from westbound I-70 to U.S. 6 and Colo. 119 was closed for more than an hour.The truck landed in Clear Creek, spilling an unknown amount of asphalt in the creek. Both saddle tanks on the truck also ruptured, spilling 100 gallons of diesel into the creek.The crash happened east of Idaho Springs where I-70 and U.S. 6 split.Hazmat cleanup crews were at the location and had floating booms in the creek to try and contain the diesel spill.The spill was the third in three weeks involving asphalt trucks crashing on mountain roads. The first two crashes occurred in Poudre Canyon, west of Fort Collins.If that happens one time, its a big concern. For it to happen three times in a short amount of time, its got our attention, said Trooper David Hall. Were going to investigate this matter to find out how they happened, why they happened, and what do we need to do to make sure this doesnt happen again.The truck was delivering a load of road base, gravel mixed with oil, to a road paving project on Highway 119, three miles north of Blackhawk.A spokeswoman for the Colorado Department of Transportation said that project will be on stand by Friday, while contractors discuss what to do to keep another accident from happening.The contractor supervising the project is the same as one of the earlier accidents, but the trucking company subcontracted, AAO, Inc. out of Commerce City, is different.7 News checked and records show that trucking company has had a clean record for the last two years.