Abstract In the northeastern United States, we have been removing dams for almost as long as we have been building them, yet many communities involved in current decisions to repair, replace, or remove a dam are not aware of this. This paper highlights some of the stories that have been recorded regarding the history of decision points for dams, including the colorful history of the Billerica Dam in Massachusetts, which has been removed and rebuilt numerous times and is now under consideration for removal for at least the sixth time in its 300 yr history. By understanding that dam removal is just one of the potential dam safety decisions that needs to be analyzed over the life cycle of a dam, and that dams are man-made structures with finite life spans, we can deconstruct the notion of dam removal as a radical concept. Dam removal is just one of many dam safety options that may be discussed over the course of a dam’s history. It is most commonly implemented when a dam no longer serves any economic purpose that justifies the expense of maintaining the dam structure. In the past, dams have been removed for many of the same reasons that we remove dams today; however, the procedures currently required to remove a dam are far more complex and highly regulated. This has led to increased documentation of dam removal efforts and now allows us to compare and categorize dam removal projects, such that the lessons learned from these projects can be incorporated into a more informed decision-making process in the future.

Abstract The Vermont copper belt includes the Elizabeth mine in South Strafford, the Ely Mine in Vershire, and the Pike Hill mines in Corinth. Of these the Elizabeth mine operated over the longest period of time, produced the highest tonnage of copper and left the largest and most complex collection of historic resources. The Elizabeth mine site is complex and represents approximately 160 years of industrial activity from 1809 to 1958. It was the site of a major 19th century U.S. copperas manufacturing plant, and several important firsts in American copper smelting. It was the site of no less than nine copper ore smelting campaigns and multiple ore concentration milling phases. The extent of industrial operations encompassed hundreds of acres. The Elizabeth mine produced an estimated 4,726,800 kg (10,500,000 lbs) of copper before its World War II revival. During the subsequent campaign the mine became the largest and most productive copper mine in New England, and yielded another 41,502,495 kg (91,495,800 lbs) of copper. Briefly during the 1950s it was one of the top 20 U.S. copper producers. The unique copperas works remains and the World War II-era remains constitute one of the largest and least disturbed historic mining sites in New England. This landscape includes the only intact cluster of historic hard-rock metal-mine plant buildings in the region. The Ely mine orebody was discovered in 1813 and explored during the 1830s, but it was most active between the mid-1850s and about 1905. Mining began seriously in 1853 with the incorporation of the Vermont Copper Mining Company. For the next 13 years the ore was shipped to east coast smelters. The mine eventually came under the control of Smith Ely, for which it is named. In 1867 the company built its own smelter on the mine site. This plant was periodically expanded to become a massive mid-19th century nonferrous metallurgical works, more than 122 m (700 ft) long with 24 smelting furnaces. By the mid-1870s the town of Ely had become a mining boomtown and in 1883, the town was the site of the “Ely War” labor conflict. The Ely mine was the only copper mine in Vermont where all technological aspects of refined copper production, from mining of raw ore to smelting of refined ingot copper, were successfully integrated on a large scale. The site geography at the Ely mine dictated a confined, straight-line flow of materials and processes, and today the historic landscape expresses copper production in a linear, understandable way. Total copper output for the Vermont copper belt mines between 1793 and 1958 has been estimated at about 65.8 million kg (145 million lbs), with about 25 million kg (100 million lbs) from the Elizabeth mine, about 16 million kg (35 million lbs) from Ely and under 4.5 million kg (10 million lbs) from Pike Hill ( Abbott, 1964 ; Howard, 1969 ). In addition to their economic contribution, the Vermont copper belt mines also contributed to the historic legacy and landscape of New England. They have left unusual stories and sites that convey the drama and impact of hard rock mining, an industry not usually associated with New England.