Quartz hill, Alaska: A case history of engineering and environmental requirements for STD in the USA

Abstract

The Quartz Hill molybdenum prospect, with an estimated tailings disposal rate of up to 80,000 tons per day, was developed through preliminary engineering design, environmental impact assessments, and permit applications during the 1970s and 1980s. The intent was to meet the stringent environmental requirements of several federal and state regulatory agencies. The case history of mine development, extending over two decades, provides a unique set of details usable by future large‐scale coastal and island mine prospects in the U.S. and elsewhere. Two fjords provided options for submarine tailings disposal (STD) with conventional deaeration and seawater mix chamber. An outfall was designed, and would be located, to produce a density current descending to fjord bottom. Innovative modeling of near‐field and far‐field tailings dispersal, and resuspension potential, was developed and applied. Of about $102,000,000 invested on the development, approximately $31,000,000 was given to environmentally related work. F...