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The new coat of paint should last a decade or longer. But to get to the top of the arch, Caltrans will have to close two northbound lanes on Saturday from 6:00 a.m. to 10:00 a.m. and two southbound lanes from 10:00 a.m. to 2:00 p.m.
The rainbows first went up in 1970 when a former Caltrans director ordered the painting just before he was about to retire.
Caltrans hopes to complete the work this weekend.
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