The deepest orebody mined at Buchans was MacLeans. It was named after Dr. Hugh J. MacLean, Asarco's chief geologist in Buchans from 1941 until his tragic death in a bush plane crash at South Pond in 1951. MacLeans was discovered in 1950. MacLeans mine shaft was completed at a depth of 3,526 feet below surface the mine is actually deeper than this due to the mining of MacLean's extension in 1983 and 1984 through a "winze" (diagonal decline) tunnel leading to "21 level." The mine produced ore from 1959 to 1981 and from 1983 to 1984. MacLeans produced a total of 3,514,989 tons of ore.