Laserfiche WebLink
�J <br />Pacific EcoRisk <br />2.4 Acute Toxicity Testing with Fathead Minnows <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. Water quality <br />characteristics (pH and dissolved oxygen ID.O.1) were determined for the test solution in each <br />test replicate prior to initiation of this test. There were 2 replicates at each test treatment, each <br />replicate consisting of 9.2 L of media in a 10-L container. The test was initiated with the random <br />allocation of 10juvenile fathead minnows into each replicate container. These containers were <br />placed in a temperature -controlled room at 20°C, under fluorescent lighting on a 16L:8D <br />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 length (to the nearest 0.1 mm) and weighed (to the nearest 0.01 g). <br />The resulting survival data for the waste treatments were evaluated to determine the LC5o using <br />the CETIS®statistical software (Version 1.6.4J,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 also 100% survival in each of the waste treatment levels. These results <br />indicate that the LC5o of this sample is greater than the "hazardous waste" toxicity threshold of <br />500 mg/L, and that this sample should not be considered "hazardous" with respect to fish <br />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 waste sample "V I". <br />Sarnple Treatment <br />Mean %n Survival <br />Lab Control <br />100 <br />250 mg/L <br />100 <br />500 mg/L <br />100 <br />750 mg/L <br />100 <br />LC5o = >750 mg/L <br />Page 2 <br />6113 <br />Pacific EcoRisk Ll�> <br />