Laserfiche WebLink
r~ . . <br />NARRATIVE <br />Whole Effluent Toxicity Test <br />Spring Inlet Water <br />CLIENT: Somerset Mining Co., P.O Box 535, Somerset CO 81434 <br />DATE: October 26, 1992 <br />PERMIT AND SAMPLE INFORMATION <br />NPDES #: CO- 0000132 <br />Type of Sample: Spring Grab <br />Dilution Water: Gunnison River <br />Date & Time of Sampling: 10-13-92/12:15 am <br />Date & Time of Test: 10-14-92/3:00 pm <br />TEST ORGANISMS AND PROCEDIIRE <br />Organism: Ceriodaphnia dubia Age: <24hrs <br />Procedure: Acute, 48 hour bioassay as specified by the <br />Water Quality Control Division of the Colorado <br />Department of Health - 1992. <br />RESIILTS - A spring sample collected above the B seam coal <br />rock in Somerset Mine was found to have an alkalinity <br />of 1690 mg/L and to cause significant mortality to C. <br />dubia with an LCso of 73 0 . <br />DISCIISSION <br />Past TIE test results support the theory that high <br />alkalinity in Somerset Mine effluent is the cause of <br />effluent toxicity to C. dubia. The results of this test <br />suggest that the inlet spring water may be a major <br />contributor to effluent toxicity by introducing high <br />alkalinity. <br />COMMERCIAL TESTING & EN GIN EERIN <br />nal Cope Wa~ermarked <br />°a dour Pro recu on <br />