ADAMS COUNTY, Colo. -- A fuel tanker spilled some of its load Wednesday morning after it rolled on the ramp from westbound 74th Avenue to westbound Interstate 76.

The rollover, which occurred just before 6 a.m., forced the closure of the ramp, and also closed 74th Avenue from Colorado Boulevard to York Street in Adams County.

The semi lost control on the ramp and ran off the left side of the roadway, smashing into a guardrail. The tanker then rolled down an embankment, with the rear of the tanker landing next to railroad tracks.

The driver, identified as Julio Perez, 34 of Denver, was taken to North Suburban Medical Center with minor injuries.

The maroon semi was operated by W.S.I Transportation of Henderson, Colo.

Hazardous materials crews were called to the the area to try to keep an estimated 8,500 gallons of gasoline from spilling into a nearby water supply. The reservoir supplies water for the city of Thornton.

Officials said the tanker began leaking gas cargo on impact and a large amount of the fuel was spilled before emergency responders were able to cap the tanker. Emergency crews were able to contain the spill.

The ramp will be closed until at least late afternoon while the fuel is off-loaded and the tanker wreckage is uprighted. The cause of the crash is under investigation.

The Colorado State Patrol said alcohol or drugs are not suspected as factors in the rollover.