Guy Chichester (February 11, 1935 – February 8, 2009) was a founding member of the Clamshell Alliance, an anti-nuclear group that led protests against Seabrook Station Nuclear Power Plant in the 1970s, which led to a broader environmental movement.
Though the Seabrook power plant was eventually built, a planned second reactor at the site was cancelled.
Several acts of protest at Seabrook, including one large demonstration that resulted in nearly 1,500 arrests, contributed to a turn public opinion against nuclear power in the USA in the 1970s.
Then Governor Meldrim Thomson, a vocal supporter of the Seabrook plant, was defeated for re-election in 1978, in large part because of voter dissatisfaction over the rising cost of plant construction.A few years before the Seabrook protests, Chichester helped rally opposition to a plan by Aristotle Onassis to build an oil refinery on Great Bay in Durham, New Hampshire.
He helped establish the national Green Party.
Chichester was also a local organizer for George McGovern's 1972 presidential campaign.Chichester was born and raised on Long Island, New York.