Heisey pioneered the exploration and development of the Sanshaw/Red Lake metal deposits located in northwest Ontario in the 1930s. The Red Lake Mine is one of the richest gold mines in the world, still in production today with annual production of 600,000 ounces gold and over 11 million ounces produced to date. Heisey obtained a Bachelor"s degree in Applied Science from the College of Applied Science (Mining) at the University of Toronto in 1922.
He enlisted in the Signal Corps of the Canadian Expeditionary Force in 1916, during the First World War.
Heisey joined the Royal Flying Corps as a Cadet, flying out of Camp Borden, Ontario, and was demobilized at the end of the war as a Royal Air Force Second Lieutenant. Heisey engaged in geological surveys for the Ontario Ministry of Natural Resources between 1919 and 1922 in Kirkland Lake and West Shinintree and conducted magnetic surveys for discovery of gold with pyrrhotite iron.
Following this, Heisey worked as an engineer with Argonaut Mines, Kirkland Lake from 1922 to 1923. In 1924 he was appointed chief engineer of Tough Oakes Gold Mines and the same year he joined the Mond Nickel Company as exploration engineer in the Quebec field
Heisey opened his own office in Kirkland Lake in 1928, coming to Toronto in 1930.
Heisey was the president of Sanshaw Mines Limited and a Managing Director of Bathurst Gold Mine Limited. at the time of his death in 1937. During Heisey"s time as president and manager of Sanshaw Mines Limited., his crew uncovered an unknown well-mineralized shear, which he stated was the most important so far discovered. Heisey was affiliated with numerous other mining corporations throughout his career where he held various roles, some of these corporations include: Manitoba and Eastern Mines Limited., Marquette Long Lac, and Russet Red Lake Syndicate.
His appointments with these mines included being in charge of surface work, consulting and direction of a new extensive diamond-drilling program, as well as consulting and analysis leading to recommendation of diamond drilling of a section of the property respectively.
Heisey also has authorship on an assessment report on Ossian Mines Limited. for the Ministry of Northern Development and Mines of Ontario. His assessment outlined analysis of the mine as well as recommendations for future work.
Heisey died at the age of 42 at Saint Michael’s Hospital in Toronto, Ontario after an illness of two months. He had three sons, Alan Milliken Heisey Senior, Lawrence Heisey and Karl Junior.