Bodega Bay's Hole in the Head has a rich history 

Arthur Dawson, Towns Section, THE PRESS DEMOCRAT
Hole in the Head is a 70-foot deep pit dug at Bodega Head in the early 1960s. It is a sort of anti-monument, a place to remember something that didn’t happen. In the late 1950s, PG&E drew up plans for power plants up and down the California coast. Though the Bodega Head plant was initially cast as a “steam-electric generating facility,” the company eventually admitted it would be a nuclear plant — one of the largest in the world at the time.
In those days there was no public input on major projects. As ground was broken and a pit excavated in the first stage of construction, public reaction to the reactor was approaching critical mass.
The Association to Preserve Bodega Head and Harbor was formed by an eclectic group of local ranchers, jazz musicians, students, Sierra Club Director David Brower, homemakers and other concerned citizens.
At a meeting in Santa Rosa, a coordinator for the state’s Atomic Energy Development Agency, frustrated by all the public comments, told the group that they should leave the project “to the experts.” This did not sit well with people who felt they needed a nuclear plant like, well, “a hole in the head.”
They began writing letters to officials and organizing creative protest rallies. Gathering at Bodega Head on Memorial Day, 1963, they released 1,500 yellow balloons into the air. Each one carried a note: “This balloon could represent a radioactive molecule of strontium-90 or iodine-131.” The balloons showed up many miles downwind, landing as far away as the East Bay and the Central Valley.
PG&E insisted it would engineer the plant to safely survive a major earthquake. The activists responded by hiring a geologist to assess the site.
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