How to Determine the Toxicity Hazardous Waste Characteristic Without TCLP

RCRA Hazardous Waste Regulations

How to Determine the Toxicity Hazardous Waste Characteristic Without TCLP

Daniel Stoehr
June 18, 2012

All too often the costly and time-consuming TCLP test method (Toxicity Characteristic Leachate Procedure) is used to determine the applicability of a characteristic waste code for Toxicity (D004 to D043) when other less expensive options which are accepted by the US EPA are available.

First, some facts about TCLP:

  • First promulgated on 3.29.90 in 55 FR 11798 to replace the EP Toxicity Test.
  • Included as Method 1311 in the EPA-approved test methods for solid waste:  SW-846.
  • The method uses acetic acid in an amount 20 times greater, by weight, of the solid portion of the sample to extract any leachable toxic waste.  After extraction and filtration, the extracted liquid (leachate) is compared to the toxicity characteristic regulatory levels at 40 CFR 261.24(a).
  • Designed to be performed on samples of ≥0.5% filterable solids, any liquids in the sample are deemed to already contain the leached toxic waste and are separated from the solid portion before it undergoes the extraction procedure described above.
  • For waste samples of <0.5% filterable solids, analysis by TCLP cannot be run; analysis to determine the concentration of toxic waste must be by total analysis.
  • It’s expensive.  Full TCLP can cost close to $1000/sample.

So, what options are available for determination of the toxicity characteristic other than analysis by TCLP?  Well…

  • Though care should be taken, 40 CFR 262.11(c)(2) allows a generator to determine the hazardous characteristics of their waste without resorting to analysis of a representative sample.  Using generator knowledge, you may:
    • Assume a waste to have a toxic characteristic and manage as such (RO 11608, RO 13472).
    • Rely on the information in a Material Safety Data Sheet (exercise extreme caution).
    • Use a combination of generator knowledge and analysis (RO 11603, RO 14695).
  • Use the oily waste extraction procedure (OWEP – Method 1330 in SW-856) for wastes containing oil or grease in concentrations of ≥1% (RO 11522, RO 12450).
  • Use total waste analysis (see below).

Section 1.2 of the TCLP reads, “If a total analysis of the waste demonstrates that individual analytes are not present in the waste, or that they are present but at such low concentrations that the appropriate regulatory levels could not possibly be exceeded, the TCLP need not be run.”  To use this option, follow this procedure:

To evaluate the regulatory status of a liquid sample (<0.5% filterable solids):

  1. Filter.
  2. Analyze for total concentration of toxic characteristic hazardous waste.
  3. Compare results directly to regulatory levels of 40 CFR 261.24(a).
  4. If no total result is greater than the regulatory levels, then the sample does not exhibit the toxicity characteristic.

To evaluate the regulatory status of a 100% solid sample (no filterable liquid):

  1. Analyze for total concentration of toxic characteristic hazardous waste.
  2. Divide the results by twenty (20) to determine the Maximum Theoretical Leachate Concentrations.
  3. Compare the Maximum Theoretical Leachate Concentrations to the regulatory levels of 40 CFR 261.24(a).
  4. If no Maximum Theoretical Leachate Concentration equals or exceeds the regulatory levels, then the sample cannot exhibit the toxicity characteristic.

The division by twenty in #2 above is known as “The Rule of 20“.  It is derived from the 20 to 1 ratio of extraction fluid (acetic acid) to the solid sample in TCLP analysis.

In order to save time and money (prices may vary, but totals analysis will always be less expensive than TCLP), when you next send a sample to the lab for analysis to determine the presence of the toxicity characteristic, direct them to perform the following:

  1. Analyze by totals analysis first.
  2. If results are <20 times the regulatory levels, then stop.
  3. If results are >20 times the regulatory levels, then run TCLP to ensure the leachable concentration of toxic constituents is below regulatory levels.

Determination of the toxicity characteristic is just one step of the waste determination process.  After you have determined the listed and characteristic hazards of your waste, you must then comply with the regulations applicable to your generator status.  Contact me to learn more about the EPA regulations for management of hazardous waste and the DOT requirements for the transportation of hazardous materials.