Colonel Franklin Matthias (1908 - 1993) was the officer-in-charge at the Hanford site.
Matthias, a civil engineer, had been a close associate of General Groves since the beginning of the Manhattan Project, and was asked to review sites in the West. Matthias and two DuPont representatives looked quickly at possible sites in Montana, Oregon, and California, as well as Washington. Matthias felt Hanford, isolated and with a good supply of water, was the best choice. Groves appointed Matthias officer-in-charge at Hanford, granting him authority over civilian operations as well as military.
Matthias left the Army in 1946. He didn't think atomic energy would amount to much in peacetime, and nothing appealed to him as much as the excitement of big construction jobs. Among the many dams he helped build until his 1973 retirement were two on the Columbia River: Wells and Wanapum, both upstream from Hanford. Wanapum held special significance, since it was named for the people of Johnny Buck, a Native American he knew and liked during the Hanford years.