From KCBS San Francisco:

Port of Oakland trucks

So far, about 4,000 trucks have been checked statewide at similar checkpoints. About 1,000 citations have been issued.

The California Air Resources Board and the California Highway Patrol were both inspecting trucks at the Port of Oakland on Wednesday, as part of a month-long campaign to ensure compliance with California’s air pollution laws.

CHP officers are making sure truck drivers have the correct license, along with valid registration. The state’s Air Resources Board is making sure truckers are complying with state air pollution laws.

Non-compliance tickets range from $300-1,800. For the most egregious offenders, tickets can cost even more.

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