As Interior secretary in the 1960s, Stewart Udall promoted the idea that government should preserve vast areas of wilderness, and so vastly expanded the country's system of national parks and monuments. He also served in Congress and later led a crusade on behalf of victims of radiation exposure. He was 90.
http://www.sfgate.com/cgi-bin/article.cgi?f=/c/a/2010/03/21/MNV81CJ2E0.DTL
