Sulfur-isotope distribution and contamination related to the Balya Pb?Zn Mine in Turkey

Abstract

Sulfur-isotope (δ34S) values and weight (%) of acid-volatile sulfur (AVS), chrome-reducible sulfide (CRS), elemental sulfur (ES), and acid-soluble sulfates were determined in Balya Mine ore rock, mine wastes, and Kocacay River and Lake Manyas sediments. Estimation of isotopic fractionation (Δ34S) between product sulfate and initial CRS (pyrite) was used to evaluate the progress of sulfide oxidation in the mine-waste area. Water- and acid-soluble sulfate produced from different mine-waste samples, such as metallurgical waste (MW) and waste rock (WR), in laboratory experiments also shows distinct δ34S values and allows identification of the acid-mine-drainage sources in the mine-waste area. Average δ34SSO4values are −1.43‰ for MW (n=4) and +2.06‰ for WR (n=8). Short (24 hr) and long (60 days) term leach experiments were considered using alternating wet/dry conditions to simulate sulfate-production capacity and metal-discharge characteristics for MW and WR piles. Release of heavy metals follows the order of Pb2+ >Mn2+ >Zn2+ >Cu2+ for these pile samples. Values of δ34SSO4 for river water that was collected after 3–4 h of heavy rainfall are close to values of δ34SSO4 for water-soluble sulfates from mine-waste piles used in laboratory leach experiments.