Links to Related Sites

Compound Lists

Phase Facts:

Speciation of Metals: Chromium

New Approach to Soil Handling for Volatiles

Sampling Volatiles In Soil by 5035

MTBE - The Next Challenge

Utilizing TPH Methods Effectively

TPH Method Overlap

Specific Petroleum Compound Testing

TPH 1664 vs. 413.1 and 418.1

TCLP vs. SPLP Extraction Procedures

Analyzing for Metals by ICP/MS

ICP/MS Qualitative All Elements Scan

What About SPLP 1312?

TCLP extractions are often misapplied. TCLP is the acronym for Toxicity Characteristics Leaching Procedure. This methodology was developed to estimate the mobility of specific inorganic and organic contaminates that are destined for disposal in municipal landfills.

The TCLP extraction is performed by subjecting the material in question to a simulated landfill leachate. Acetic acid was chosen as the extraction fluid because it is the major component of typical municipal landfill leachates. The pH of the acetic acid buffer solution is maintained at 4.93. This sample/acetic acid mixture is subjected to an 18 (( 2 hour) rotary extraction, designed to accelerate years of material/landfill exposure in the shortest possible time. After extraction, the resulting liquid is subjected to analysis utilizing a list of 39 contaminants that are contained in the EPA’s TCLP Final Rule. These contaminants include eight metals, eleven volatile organic compounds, twelve semi-volatile organic compounds, six pesticides, and two herbicides.

Consequently, the TCLP test should be limited to determining if a waste should be considered a RCRA-regulated waste or, if it can be disposed of in a municipal (sanitary) landfill.

The TCLP procedure may be misapplied in two ways. First, analysis of compounds not included in the methods development or TCLP Final Rule may provide technically invalid results. An example of this would be the utilization of the TCLP extraction for cyanide. The extraction procedure itself will result in the loss of simple cyanide complexes, representing the most toxic form of cyanide.

The second way the TCLP is misapplied is by use of the procedure for materials that are not destined for landfills where interaction with acetic acid is likely. In these cases an alternative procedure, the SPLP, (Synthetic Precipitation Leaching Procedure) 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 landfill 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.