ABSTRACT
The TCLP [6] is the regulatory standard in the United States for the classification of a waste stream as hazardous or non-hazardous. It was designed to simulate the response of a waste disposed in a municipal landfill in the presence of organic waste. The decomposition of the organic matter in these landfills is known to generate organic acids which are simulated in the TCLP by the use of acetic acid. However, the highly alkaline nature of Portland cement solidified waste forms can quickly neutralize the acid present in the TCLP extraction solution and shift the pH of the test solution to significantly higher values [8]. This shift in the pH can result in a significant change in the solubility of the hazardous metal species [9]. In the past work we concluded that the TCLP may not accurately reflect what occurs in the cement waste form [2-5].
