YUKON EXPLORATION AND GEOLOGY 2003 271 Post-mining hydrogeochemical conditions, Brewery Creek gold deposit, central Yukon

• Main Authors: Seth H. Mueller, Craig J. R. Hart, Richard J. Goldfarb, Leeann Munk, Rick Diment
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Laura Creek; Yukon; Alaska
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.518.8954; http://publications.gc.ca/collections/Collection/R71-41-2003E(19).pdf

A reconnaissance-level study of post-mining hydrogeochemical conditions was carried out at the Brewery Creek gold deposit within the Tintina Gold Province. The deposit is characterized by epizonal mineralization with a consistent arsenic-gold-mercury-antimony geochemical signature. Surface discharges and seeps in the area are naturally alkaline (pH=7.6-8.2), Ca-HCO3 ¯-SO4 ¯ waters. Upstream from the recognized mineralization, waters contain <3 μg/L As and <1 μg/L Sb. Water samples immediately downstream from the ore bodies show maximum concentrations of 18 μg/L dissolved and 47 μg/L total arsenic, and 18 μg/L dissolved and 21 μg/L total antimony. Two kilometres below the mineralization, on lower Laura Creek, arsenic concentrations are diluted to background levels of <3 μg/L, and antimony levels are still slightly elevated at 9-10 μg/L. Comparison with hydrogeochemical data from Donlin Creek, an undeveloped epizonal deposit in Alaska, indicates that elevated concentrations of a few tens of μg/L arsenic and antimony are typical of waters draining such gold systems, regardless of their state of development. In addition to their