2008-10-22_REPORT - C1981008 (3)

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• Table of Contents Abstract Page 2 Methods Page 2 Results Page 3 Narrative & Discussion Page 4 Table 1 - Colorado Test Conditions Page 5 Abstract Table 2 - Methods and Equipment Page 5 References Page 5 Discharge Monitoring Report Form(s) Pg. 6-7 Reference Toxicity Data Chart(s) Pg. 8 Supplement Forms' Pg. 9 SGS North America, Inc. conducted a two species chronic bioassay on Western Fuels New Horizon Mine effluent discharge. This discharge has been designated as outfall007. The purpose of this bioassay was to determine if the facility complies with the chronic WET portion of the Colorado State Permit System Authorization to Discharge. The test organisms utilized were the fathead minnow (Pimephales promelas) and cladoceran (Ceriodaphnia dubia). Test results indicate that the effluent was not chronically toxic to fathead minnow or to Ceriodaphnia dubia survival. Therefore, outfall 007 is in compliance with the chronic WET portion of its Colorado State Discharge Permit for thefourth quarter of 2007 0 Methods A two species chronic bioassay was conducted with effluent from Western Fuels New Horizon Mine, Outfall 007. An effluent composite sample was collected on October 22, 2007, stored on ice, and delivered to SGS North America Inc. on October 23, 2007. The effluent samples were received at a temperature of 3.40 C and 4.3° C (separate coolers) and assigned sample tracking number TA7-JO- P032-001. The bioassay was initiated approximately 24 hours after sample collection. Subsequent samples were collected October 24, 2007. Because of the remote location of the facility, two concurrent samplings events were utilized for this examination. Sufficient sample volume was collected for the entire test. Testing was conducted in accordance with the most recent protocols specified by the Water Quality Control Division of the Colorado Department of Health (1998) outlined in Table 1. Basic characteristics of the effluent and dilutions were measured by the methods and equipment outlined in Table 2. The tests exposed the cladocerans, Ceriodaphnia dubia, and fathead minnows, Pimephales promelas, to five concentrations of effluent, 100%, 75%, 50%, 25%, and 12.5%, prepared using reconstituted laboratory water. Control replicates were exposed to 100% laboratory water. Statistically, fathead minnow survival and growth data were both analyzed for significant differences using Dunnett's test. Ceriodaphnia dubia survival and reproduction data were analyzed for significant differences using Fisher's Exact Test and Wilcoxon's Rank Sum Test, respectively. IC25 values were determined using the Bootstrap Linear Interpolation method. 1 Supplemental forms include statistical analysis and chain-of-custody forms 2 Inhibition Concentration at 25% reduction 2