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 byepizonal 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 ¯-SO4²¯ waters. Upstream from the recognized mineralization, waters contain <3 ¿g/L As and <1 ¿g/L Sb. Water samples immediately downstream from the ore bodies show maximum concentrations of 18 ¿g/L dissolved and 47 ¿g/L total arsenic, and 18 ¿g/L dissolved and 21 ¿g/L total antimony. Two kilometres below the mineralization, on lower Laura Creek, arsenic concentrations are diluted to background levels of <3 ¿g/L, and antimony levels are still slightly elevated at 9-10 ¿g/L. Comparison with hydrogeochemical data from Donlin Creek, an undeveloped epizonal deposit in Alaska, indicates that elevated concentrations of a few tens of ¿g/L arsenic and antimony are typical of waters draining such gold systems, regardless of their state of development. In addition to their usefulness for the construction of geoenvironmental models, these data also provide information for establishing exploration programs utilizing water sampling.
