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Client: Western Fuels <br />Site: New Horizon Mine 007 <br />CO- 0000213 SCG Project No.: 311693.B <br />Test Procedures <br />Upon receipt at the lab, samples are analyzed for alkalinity, hardness, conductivity, <br />dissolved oxygen, ammonia, chlorine and pH. Alkalinity and hardness are determined <br />titrimetrically according to methods described in Hach Chemical Company'. Ammonia is <br />measured by a Thermo Orion ion- selective electrode according to the procedures in <br />APHA/AWWA/WEF Conductivity, dissolved oxygen and pH probes were used to take these <br />measurements. <br />The test followed procedures in EPA' and CDPHE guidelines. Exposure concentrations <br />included control (0 %), 20 %, 40 %, 60 %, 80 %, and 100% mixtures, diluted with moderately hard <br />laboratory reconstituted water. <br />Individual Ceriodaphnia dubia were placed in 30m1 plastic containers containing <br />approximately 15m1 of exposure medium. Ten replicates at each concentration were used. The <br />animals were fed daily with the YCT mixture and an equal volume of the green algae <br />(Selenastrum capricornutum). The exposure medium was changed daily in each container and <br />the number of young released overnight were counted and recorded. Young were removed from <br />the containers daily and discarded. Routine measurements were made each day of temperature, <br />dissolved oxygen and pH before and after the water changes. <br />Fathead minnow were exposed in 500m1 plastic cups to which 250m1 of media was added <br />and replaced daily. Four replicates were used at each concentration. Ten fish, less than 24 -hours <br />old, were placed in each cup. The fish were monitored daily for survival and fed live Brine <br />shrimp at least twice per day. After seven days, the fish were removed from the cups, <br />euthanized, and then placed in aluminum pans and dried in an oven for a minimum of six hours <br />at 100 °C. The pans were then weighed on a five -place analytical balance to determine the <br />average dry weight of the fish from each replicate. <br />Data Analysis <br />Data from the test(s) were analyzed on a personal computer using the TOXCALC <br />package developed by Tidepool Scientific Software. Statistical tests used in the analyses are <br />shown in Table 1. Test acceptability was determined using control survival and performance <br />criteria, concentration- response relationships and percent minimum significant differences <br />(USEPA 5,6) <br />SeaCrest Group 6 <br />