EPA Toxic Characteristic Leaching Procedure

The Resource Conservation and Recovery Act (RCRA) identifies endrin as a hazardous waste in two ways (1) when it exceeds a toxicity characteristic leaching procedure test concentration of 0.02 mg/L (EPA 1980a) and (2) when it is discarded as a commercial chemical product, off-specification species, container residue, or spill residue (EPA 1980a). 

The toxicity characteristic leaching procedure may be subject to misinterpretation if the compounds under investigation are not included in the methods development or the list of contaminants leading to the potential for technically invalid results. However, an alternative procedure, the synthetic precipitation leaching procedure (SPLP, EPA SW-846 Method 1312) may be appropriate. This procedure is applicable for materials where the leaching potential due to normal rainfall is to be determined. Instead of the leachate simulating acetic acid mixture, nitric and sulfuric acids are utilized in an effort to simulate the acid rains resulting from airborne nitric and sulfuric oxides. 

Hazardousness Having a hazardous property. A chemical, procedure, or event that creates a substantial threat to human health and life. The United States Environment Protection Agency (US EPA) classifies hazardous wastes by four characteristics, including corrosivity (very alkaline (basic) (pH > 12) or acidic (pH 2) wastes), ignitability, toxicity, and reactivity (40 Code of Federal Regulations 261.20-261.24) (see Appendix E compare with toxicity characteristic and toxicity characteristic leaching procedure, TCLP). 

US EPA United States Environmental Protection Agency TCLP Toxicity characteristic leaching procedure ANC Acid neutralizing capacity procedure... 

These metals are considered hazardous under the Resource Recovery and Conservation Act of 1987 (RCRA) [4]. The RCRA metals occur in chemical forms that are soluble or insoluble in groundwater. The soluble species are of concern from the dispersibility viewpoint. Hence, the test criterion to evaluate whether a given waste stream needs stabilization prior to disposal is based on how much a given hazardous metal dissolves in water in a standardized test. This EPA test, called the Toxicity Characteristic Leaching Procedure (TCLP) [5], is used not only to identify which waste streams need treatment, but also to assess whether the treated waste form is suitable for disposal. This test also sets limits on how little of a hazardous metal is permitted to leach out from a given waste to pass the waste for disposal. If the test determines that the waste is not suitable for safe... 

Toxicity characteristic leaching procedure (TCLP) us EPA [13] Measures the solubility of hazardous constituents. Used to determine if a waste is hazardous and to pass/fail the waste form for disposal... 

For remediation purposes it is important to determine Pb concentrations in soils using the toxicity characteristic leaching procedure (TCLP) (U.S. EPA, 1992). Soils that have TCLP-Pb concentrations below 5 mg L" are considered non-hazardous and can be disposed of in landfills. Although the procedure has little scientific value, it has been used widely for evaluating soil contamination and remediation. 

U.S. EPA (1992). Toxicity characteristic leaching procedure (Method 1311). In Test Methods for Evaluating Solid Waste, Physical/Chemical Methods, Office of Solid Waste, U.S. Enviromnental Protection Agency, Washington, DC. 

US-EPA provides two leaching test methods. One is the Toxicity Characteristic Leaching Procedure (EPA SW 846 Method 1311), and is called the TCLP for short. The other is the Synthetic Precipitation Leaching procedure (EPA SW—846 Method 1312), and is called the SPLP. The TCLP is intended to simulate dissolution of waste materials inside a landfill, and is the only leaching test specified by the regulation for characterization of the hazardous waste (40 CFR 261.24 Toxicity Characteristic, waste code D004-D043) under the Resource Conservation and Recovery Act (RCRA). 

Because the EPA regulates hazardous wastes in order to protect the environment (not to prevent human exposures), they define hazardous properties differently than agencies such as OSHA, whose purpose is to protect humans. According to the EPA, hazardous waste is chemical material that has been or will be discarded and it has one or more hazardous characteristics or is on one of four lists (called F, K, P, and U Lists). The characteristics regulated are flammability, corrosivity, reactivity, or toxicity. Toxicity is defined as a liquid with concentrations above those listed on the Toxicity Characteristic Leaching Procedure (TCLP) list or< > a solid that when extracted by the TCLP, has a resultant concentration about listed concentrations. This definition has little to do with the human exposure definition of toxicity that you will find in the toxicology sections of this book. 

Toxicity Characteristic Leaching Procedure, U.S. Environmental Protection Agency, http //www.epa. gov/osw/hazard/teslmethods/sw846/pdfs/131 l.pdf, 2(X)8. 

Toxicity characteristic leaching procedure (TCLP) is the method mandated by the U.S, Environmental Protection Agency (EPA) for determiifing how much toxic material is likely to leach out of solid wastes. A short description of the TCLP method is provided here. For an exact description of the process, the reader should study Method 1311 in EPA Publication SW-846 [5],... 

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