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• <br />Pacific EcoRisk <br />2.4 Acute Toxicity Testing with Fathead Minnows <br />• <br />Environmental Consulting & Testing <br />This hazardous waste evaluation was run at sample concentrations of 250, 500, and 750 mg/L, <br />with a Lab Control consisting of the same synthetic EPA "soft" water. There were 2 replicates at <br />each test treatment, each replicate consisting of 9.2 L of media in a 10-L container. Water quality <br />characteristics (pH and dissolved oxygen [D.O.]) were determined for the test solution in each <br />test replicate prior to initiation of this test. The test was initiated with the random allocation of 10 <br />juvenile fathead minnows into each replicate container. These containers were placed in a <br />temperature -controlled room at 20°C, under fluorescent lighting on a 16L:8D photoperiod. <br />Each day, each replicate container was examined, and the number of live fish in each was <br />recorded. Routine water quality characteristics (temperature, pH, and D.O.) of the treatment <br />waters were measured and recorded for each replicate container each day. <br />After 96 (t2) hrs, the test was terminated and the number of live fish in each replicate container <br />was determined. The fish in a randomly selected Lab Control treatment replicate were then <br />euthanized and measured for total length (to the nearest 0.1 mm) and weighed (to the nearest <br />0.01 g). The resulting survival data for the waste treatments were evaluated to determine the <br />LC5o using the CETIS® statistical software (TidePool Scientific, McKinleyville, CA). <br />3. RESULTS <br />3.1 Effects of the Waste Sample on Fathead Minnows <br />The results of this test are summarized in Table 1. There was 100% survival at the Lab Control <br />treatment. There was X95% survival at each test treatment, none of which was significantly less <br />than the Lab Control. These results indicate that the LC5o of this sample is greater than the <br />"hazardous waste" toxicity threshold of 500 mg/L, and that this sample should not be considered <br />"hazardous" with respect to fish toxicity. <br />The test data and summary of statistics for this test are presented in Appendix B. <br />Table 1. Results of the hazardous waste toxicity evaluation of the sample <br />"Sample IA". <br />Sample Treatment Level <br />Mean To Survival <br />Lab Control <br />100 <br />250 mg/L <br />100 <br />500 mg/L <br />100 <br />750 mg/L <br />95 <br />Page 2 L <br />5112 <br />