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Narrative and Discussion <br />) <br />PERMIT AND SAMPLE INFORMATION <br />NPDES permit #. <br />Type of sample: <br />Date and time of sample(s): <br />Date and time of test start: <br />Dilution water: <br />Receiving temperature(s): <br />CO-0000213 <br />Effluent Composite <br />9/29/09 11:15, 10/1/09 12:00 <br />9/30/09 11:30 <br />Reconstituted Laboratory Water <br />2.1 °C, 2.3°C, 1.4°C <br />• TEST ORGANISMS <br />Fathead minnow <br />Ceriodaphnia dubia <br />Brood isolation date/time: <br />Age: <24 hrs <br />Age: 0-3 hrs <br />9/30/09 8:00 <br />• PROCEDURE <br />Chronic bioassays as outlined in the most recent protocols specified by the Water Quality Control <br />Division of the Colorado Department of Health (1998). <br />• DISCUSSION <br />According to the Western Fuels New Horizon Mine discharge permit (CO-0000213), a chronic <br />WET test is failed whenever there is a statistically significant difference in lethality between the <br />control and any effluent concentration less than or equal to the Instream Waste Concentration. <br />The IWC for this permit has been determined to be 100%. <br />By this definition, the test results indicate that the effluent was not chronically toxic to <br />fathead minnow or to Ceriodaphnia dubia survival, Therefore, outfall 007 Is In compliance <br />with the chronic WET portion of its Colorado State Discharge Permit for the fourth quarter <br />of 2009. <br />• DATE OF REPORT <br />November 23, 2009 <br />reviewed by: St anie Green Hawki <br />Supervisor'BiMssay Laboratory