ENVIRONMENTAL SITE ASSESSMENT OF IRON ACID MINE DRAINAGE AT THE ABANDONED STELLAVILLE MINE, DEKALB JUNCTION, NEW YORK

An environmental site assessment (ESA) was conducted at the abandoned Stellaville Mine, south of DeKalb Junction in northern New York. A pyrite mine in the late 1800’s and early 1900’s, surface water now runs over mining tailings into Elms Creek, which feeds into the Grasse River. Operations once consisted of three deep mine shafts, extracting pyrite from veins found in Grenville age gneiss. ESA objectives were to determine if iron acid mine drainage (AMD) contamination was present and if the AMD runoff was having an impact on the local watershed. As part of a senior research capstone project in the Fall of 2014 and Spring of 2015, students biweekly measured field parameters (pH, temperature, dissolved oxygen - DO, total dissolved solids - TDS, conductivity, turbidity, and discharge) and collected water samples. Laboratory analysis was conducted for metals (total, particulate, and dissolved iron, manganese, and aluminum), hot acidity, alkalinity, and sulfates. There were four sample locations: 1- primary AMD runoff channel, 2- cumulative AMD runoff channel, 3- upstream of runoff confluence in Elms Creek, 4- downstream of runoff confluence in Elms Creek. During the Fall 2014, sample locations 1 and 2 had on average low pH (2.68), low DO (2.21 mg/L), high TDS and conductivity (2960 ppm and 4.12 mS, respectively), high hot acidity (54.84 meq/L), no alkalinity (0 mg/L as CaCO3), and high dissolved metals (746 mg/L iron, 5.45 mg/L manganese, 168.5 mg/L aluminum, and 3250 mg/L sulfate). These results are comparable to other iron AMD sites in western Pennsylvania and correlation plots (e.g. iron vs pH, iron vs DO, iron vs TDS, iron vs conductivity) indicate the presence of AMD contamination (R² values > 0.9). In contrast, the two Elms Creek sample locations had on average neutral pH (7.8), healthy DO levels (8.76 mg/L), low TDS and conductivity (201.25 ppm and 0.26 mS, respectively), negative hot acidity (-0.90 meq/L), low alkalinity (9.07 mg/L as CaCO₃), and low dissolved metals (0.33 mg/L iron, 0.19 mg/L manganese, 0.011 mg/L aluminum, and 16.5 mg/L sulfate), indicating normal water quality, typical for the region. One-Way ANOVA tests for variance indicated no impact by AMD runoff for pH, dissolved oxygen, and total dissolved iron (all p=values > 0.05) on Elms Creek. Spring assessment indicated no significant different in water quality.