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Metals Analysis Discussion <br /> The Calif a Code of Regulations, Title 22, Section 66261, lists the criteria for <br /> determin whether or not wastes are hazardous. In the case of wastes potentially <br /> contaminat with metals, wastes can be considered hazardous based upon either the total <br /> metal coat nt in the waste or the amount of soluble metal in the waste. Therefore, two <br /> standards 'st for each metal, the Total Threshold Limit Concentration (TTLC) and the <br /> Soluble eshold Limit Concentration (STLC). Accordingly, two types of tests also <br /> exist, the total metals test, and the waste extraction test (known as the "WET' test) for <br /> soluble metals. <br /> If a waste ple is tested for total metals, and the result equals or exceeds the TTLC <br /> value for y metal, then the waste is considered hazardous (assuming sample <br /> representati eness, laboratory QC, etc. are not factors). If the total metal result is less <br /> than the C, but greater than 10 times the STLC value, the sample may be hazardous, <br /> and a WET test must be performed to characterize the waste. This is because the WET <br /> test for sol ble metals has a ten-fold dilution when compared to the total metal test <br /> procedure. This yields a theoretical limit that.the result from a WET test of the same <br /> sample coul be as much as (but not exceed) 1/10 of the total metal test result. Once <br /> performed, the result of the WET test exceeds the STLC value for any metal, the waste <br /> is hazardous. <br /> Example <br /> Concentrati ns greater than the STLC were detected for total Ni and total Pb in a sample. <br /> However, e concentrations are not ten (10) times greater than the STLC values. WET <br /> results woul therefore, not yield extraction concentrations greater than the STLC limits. <br /> As a result, Ts were not performed... The concentrations are not sufficiently high to <br /> produce extractable concentrations great enough to be considered a hazard. <br /> Perform total metals test j <br /> I <br /> Greater than TTLC no , Greater than 10n STLC <br /> i <br /> Yes ! <br /> i <br /> Perform WET test <br /> J. <br /> es �---- Greater than STLC <br /> no <br /> V ui <br /> H zardous , Non-Hazardous — <br />