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TCLP vs. SPLP: The Difference

When it comes to metal testing, there is often a discussion about which test is better, the TCLP or the SPLP. Both tests are designed to simulate and help in the analysis of leachate. There are a lot of similarities in both of these tests and they both have comparable procedures.

However, in this discussion we aren’t going to identify the similarities between TCLP and SPLP; instead, we are to discuss the various differences between the tests, and demonstrate which one is the better choice when looking for sediments in various materials.


The Synthetic Precipitation Leaching Procedure, SPLP, is used to test for certain materials on the surfaces exterior, which get exposed due to rainfall. It determines and reveals the types of organic and inorganic materials present in different liquids, soil/dirt and waste materials. It is a test that is used to determine the leaching abilities present in the materials being tested.

The issue with the SPLP test is that it is not the standard method for determining the toxic materials present because of its limitations. It is limited to only detect the metals that are present on the surface; hence it is deemed inadequate for comprehensive toxicity testing.


TCLP or the Toxicity Characteristic Leaching Procedure is a testing procedure designed to test the toxicity levels within liquids, solids or other waste materials. It is the only test that has been determined to detect the exact amount of leachate that certain materials can produce. The RCRA (Resource Conservation and Recovery Act) requires organizations working in the waste management industry to perform this test on their hazardous waste.

As a result, the TCLP analysis is the only test that can find all the toxic materials correctly. Its ability to perform such accurate analysis makes it the preferred testing method for the Environmental Testing Industry.

We hope that the information above has provided you with useful information regarding the benefits of TCLP analysis. Our lab performs accurate TCLP testing, with a quick turnaround time. Contact us ((863) 682-5897) and learn more about the TCLP and other testing services that we offer.