The key to understanding the Toxicity Characteristic Leaching Procedure (TCLP) is being aware of which leaching solution is being used.

Although most people only look at the final results of the TCLP (EPA SW846 Method 1311), there are several important things to know about the actual test procedure.

  • There is a preliminary evaluation in the TCLP that is used to establish the initial pH of the waste which determines whether to continue with Solution 1 (a dilute acid with a pH of 4.93) or Solution 2 (a strong acid with a  pH of 2.88).
  • If the initial pH of the waste is less than 5, then Solution 1 is used.
  • If the pH of the waste is above 5 at the end of the pre-test then Solution 2 is used. Since it is a stronger acid, higher concentrations of metals will leach out using Solution 2.

Occasionally, EnviroBlend clients notice inconsistent TCLP results and contact an EnviroBlend representative. After looking into it further, the laboratory typically finds that they were not consistently utilizing the correct TCLP preliminary procedure. This, of course, can lead to disposing of non-hazardous waste as hazardous or hazardous waste as non-hazardous. Both situations are risky and expensive.

It is important to make sure laboratories are running the pre-test for each sample.

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Case Studies

Columbia Development Corporation – South Carolina

Remediated over 500 tons of lead-impacted soil at a potential brownfield redevelopment site. Rendered the soil nonhazardous without additional treatment. Met the client’s 2-week time frame, completing the project prior to implementation of UTS standards. Performed the project at one-half the cost of the alternative – disposing in a hazardous waste landfill. Interested in more [...]

Old Industrial Facility – Georgia

Lead-contaminated soil was treated at this old industrial site at 6% dosage of EnviroBlend. Interested in more stories like this? Fill out the form below for a free download. Notice: JavaScript is required for this content. These case studies are examples of the extensive work EnviroBlend has completed across the United States. For more information [...]

Former Shooting Range – North Carolina

Stabilized 2,500 tons of lead contaminated soil from firing range with EnviroBlend 90/10 Coarse. Soil had to meet SPLP and MEP testing requirements. Interested in more stories like this? Fill out the form below for a free download. Notice: JavaScript is required for this content. These case studies are examples of the extensive work EnviroBlend [...]