Buried treasure

Cal trans workers, were excavating near 15 Fwy Baseline over pass, for a cement column to sustain a bridge, the massive hole was 50 feet deep by 20 feet wide.
The hole widen as they got deeper and came across a tunnel. That was there since the 1930’s
As they ascended into the tunnels. They discovered a metal box, with a old style lock. Intact they broke open and found Gold bars, silver coins and a letter containing facts about the box, they best estimate value of 400k to 600k total, the men will receive bonuses and vacation time paid for their find.