Editing Toxicity characteristic leaching procedure (section)

==Procedure==
TCLP comprises four fundamental procedures:
* Sample preparation for leaching
* Sample leaching
* Preparation of leachate for analysis
* Leachate analysis

In the TCLP procedure the pH of the sample material is first established, and then leached with an [[acetic acid]] / [[sodium hydroxide]] solution at a 1:20 mix of sample to solvent. For example, a TCLP jug may contain 100g of sample and 2000 mL of solution. The leachate mixture is sealed in extraction vessel for general analytes, or possibly pressure sealed as in zero-headspace extractions (ZHE) for [[volatile organic compound]]s and tumbled for 18 hours to simulate an extended leaching time in the ground. It is then filtered so that only the solution (not the sample) remains and this is then analyzed.