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-- <br /> <br />Enviro-Chem Analytical, Inc. Acute Toxicity Testing <br />685 West Gunnison Avenue, Suite 108 West Elk Mine -October 2007 <br />Grand Junction, CO 81505 Outfall 017 <br />2 Species <br />Each day test chambers were observed for survival. At test termination, the fish <br />were euthanized. <br />Daphnia magna - <br />Four replicates per exposure concentration were tested with five organisms per <br />test chamber. Organisms were obtained from Aquatic Biosystems Inc. Fort <br />Collins, Colorado and cultured in Enviro-Chem with hard water containing an <br />alkalinity of 1200-1500 mg/L. Only neonates which brooded out in this hard water <br />and <24 hours old were utilized for the test. Test chamber consisted of 50 mL <br />glass beakers 25 mL of test solution. Daphnia magna were fed prior to the <br />beginning of test green algae (Selenastrum capricomutum) obtained from <br />Aquatic Biosystems Inc, Fort Collins, Colorado. No additional micro-nutrients <br />were added to Hard water as algal suspensions have already been fed the <br />proper amounts of nutrients per USEPA guidelines. Test solution was renewed <br />daily at approximately 24-hour intervals from the original test initiation time. <br />Each day test chambers were observed for survival. <br />Test Acceptability <br />For the fathead minnow test to be acceptable, minimum control organism <br />survival must be >/=90%. <br />Daphnia magna control organism survival must be >/=90%. <br />Statistical Analyses <br />Formal statistical analysis of the acute data was completed as necessary. All <br />statistical analyses were completed using ToxCalc v5.0.23 obtained from <br />TidePool Scientific Software and Michael Ives. <br />If appropriate, the test's acute data was subjected to analyses for normality and <br />homogeneity. LC50s were determined using the appropriate method as per the <br />EPA data flow sheet. <br />4 <br />Results <br />Effluent Chemistry Results <br />