The crash was reported at about 4:45 a.m. and is blocking the connector ramp from southbound Interstate Highway 680 to eastbound state Highway 4, CHP Officer Pacheco said.
About 10 to 15 gallons of fuel spilled onto the roadway because of the crash, CHP Officer Kevin Kroncke said.
An ambulance was called but Kroncke did not know what, if any, injuries were suffered in the crash.
A Sig-alert was issued at 4:50 a.m. Kroncke said the ramp is not expected to reopen until after 8 a.m. when the spill is cleaned up and the big rig is cleared from the roadway.
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