The Beatson Copper Mine and the abandoned mining community of Latouche sit at the base of Mount Beatson, near Powder Point at the northwest tip of Latouche Island in Prince William Sound, about 82 miles (132 km) southwest of Cordova and 57 miles (92 km) southeast of Whittier, Alaska. Latouche Island lies between Montague Strait to the east and Latouche Passage to the west. Captain Nathaniel Portlock first named it Foot Island in 1787. Captain George Vancouver renamed it Latouche in 1794, presumably after Louis-René L. de Latouche Tréville, a famous French naval commander of the time. The mine was named after Andrew K. Beatson, a prospector who discovered and staked a series of ore deposits on the island in the late 1890s. The islands and mountains in Prince William Sound represent a major portion of one of the world’s largest accretionary complexes now called the Southern Margin Composite terrane, which comprises rocks of the Orca Group, Valdez Group, and McHugh Complex. Latouche Island is formed by the Orca Group and consists of turbiditic sedimentary rocks that developed during the late Paleocene to early Eocene (about 60 million to 50 million years ago): mostly graywacke sandstone, siltstone, mudstone, slate and some conglomerate. The ore bodies at Latouche lie in a fault zone that extends almost the full length of the island. The Beatson mine sits on the Beatson Fault, one of the major faults in the zone, where the principal ore body consisted of chalcopyrite, pyrrhotite, and pyrite in grains scattered through the altered country rock and in small veinlets associated with quartz.
The Beatson Mining Company started producing copper sulfide ore in 1904. In 1907 the Alaska Syndicate owned by John P. Morgan and the Guggenheim family, purchased the mine; in 1910 the Kennecott Copper Corporation acquired it. From 1904 to 1930 the Beatson copper mine was Alaska’s largest in terms of ore extracted, with more than 6m tons processed at Beatson compared with about 4.5 million tons mined and milled from the Kennecott mines near McCarthy. Kennecott mixed the lower-grade sulfide copper ore from the Beatson mine with the much higher-grade copper-sulfide concentrates from the McCarthy area to provide an appropriate metallurgical feed for smelters in Tacoma, Washington. The main ore body at the Beatson mine was accessed from a vertical shaft 325 feet (100 m) deep and two horizontal adits with a combined length of 1,000 feet (304 m) at 250 feet (76 m) below sea level. A major engineering challenge was keeping the underground workings from being flooded with seawater. In 1910 Frank Rumsey Van Campen was hired as chief mining engineer and designed a sophisticated cofferdam system to prevent flooding. He was married to Helen Van Campen, who documented her life at Latouche with stories and photographs that were published in national periodicals. The mine peaked from 1917 to 1918, when about 300 people worked at the Beatson mine and about 4,000 lived on Latouche Island. The mine closed in 1930, reportedly because of low copper prices and little remaining high-quality ore; water flooded the glory hole when the pumps were stopped.
In 1962 the Kennecott Copper Corporation retained the mineral rights but sold the property and surface rights to James Sumpter, operating as the Latouche Island Development Corporation, which demolished the mine-related structures. In 1971 Chugach Alaska Corporation acquired the land surrounding the former mining area under the Alaska Native Claims Settlement Act, and the state of Alaska owns the intertidal lands and the nearby Horseshoe Bay State Marine Park. The mine property was sold in 1976 and again in 1978. Donald Marino, operating as Rare Earth, Inc., subdivided the property, built roads and an airstrip using waste rock from the mine and began selling parcels for residential or recreational use. In 1989 the mineral rights were purchased by Minaska, Inc., a subsidiary of Rio Tinto Corporation. In 2013 the Alaska Department of Environmental Conservation was informed of potential contamination from mine tailings at the former Beatson mine property. A large volume of copper tailings is present in the uplands and marine intertidal area. The oxidation of iron sulfide ore such as pyrite and pyrrhotite caused by weathering releases small quantities of sulfuric acid. This was exacerbated by crushing the host rock during the ore-concentration process, which increased the surface area exposed to weathering and subsequently the rate of acid formation. Acid mine drainage is visible throughout the mine area and consists of yellow and orange precipitates in the surface water. Since 2016 Rio Tinto has been investigating possible environmental impacts at the site and has purchased many of the residential lots affected by the former mine. Read more here and here. Explore more of Beatson Copper Mine and Latouche Island here: