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Sparger Hazardous Waste Te` :ample AC27217, AC27218 Novemb 993 Page ♦ 2 INTRODUCTION An acute toxicity test was performed on samples AC27217 and AC27218. The samples were submitted for testing on November 2, 1993. Testing was initiated on November 4, 1993. The test was a 96 hour static acute bioassay for hazardous waste samples using the minnow, Pimephales promelas. The test was performed following procedures outlined in Polisini and Miller (1988). The static nonrenewal test was conducted for a 96 hour exposure period. Each sample was tested using three concentrations to determine whether it should be classified as a hazardous waste according to the criteria established in the California Code of Regulations Title 26, Section 22-66261.24(6). These criteria state that wastes are to be classified as hazardous if an aquatic toxicity test conducted with fathead minnows (Pimepha/es promelas) results in LC50 values less than 500 ppm (mg/1). METHODS Test organisms were obtained from Aquatic Resources, and were held at 20° C for more than ten days before testing. Fish were 45 days old at the start of the tests on November 4, 1993. Test conditions are summarized in Table 1. The test was conducted in a temperature controlled room at 20 :t 20C, with a photoperiod of 16:8 L:D. Each test treatment used two replicates with ten organisms per replicate. Test chambers were 5 gallon tanks with 10 liters of test solution per replicate. Concentrations tested were 750 mg/I, 500 mg/I, and 250 mg/I, as recommended for screening assays. Aliquots of the sample were weighed into screw-top Erlenmeyer flasks, 200 ml of dilution water were added to each flask, and the flasks were shaken on a v✓rist action shaker for six hours. Dilution water was EPA soft water prepared with reagent grade chemicals and Super-Q water following EPA protocol (1.990). The samples were added to the test tanks and the test was initiated by randomly adding ten minnows to each tank. Survival and water quality parameters were measured and recorded daily. QUALITY CONTROL As part of an ongoing quality control program, a reference toxicant test was conducted within the week prior to the hazardous waste tests. Reference toxicant test results are summarized in Table 1. Reference toxicant test data sheets and statistical analyses are included in Appendix B. The Pimephales promelas reference toxicant test used EPA Mod Hard as the diluent control, and test concentrations of 3.1, 6.25, 12.5, 25, and 50 mg/I sodium dodecyl sulfate. The test was conducted for a 96 hour exposure period, under the same test conditions as the hazardous waste tests. Review of test results showed that the control treatment had 100% survival at 96 hours, meeting test acceptability criteria of at least 90% survival. The LC50 was computed by the Probit Method to be 23.2 mg/l, within one standard deviation of the lab mean of 24.16 mg/I, based on 23 tests. This reoon is abb..cab a Only to the samoie•ace've_o by the laboratory The liability of the(aboraicxy is limCco To the amount bail br!^s eoCrr Tres rap;a exclusive use of tl a c,I to Ill IT is ad Tessec ar'd u,,r the COnbgiOn that the oiler,assumes alt ,,ile'onher c,lil Lc- ^ "e X11 or t5!o—r-'s