You are here:
Background information for the Leaching environmental Assessment Framework (LEAF) test methods
Garrabrants, A. C., D. S. Kosson, H. A. van der Sloot, F. Sanchez, AND O. Hjelmar. Background information for the Leaching environmental Assessment Framework (LEAF) test methods. U.S. Environmental Protection Agency, Washington, DC, EPA/600/R-10/170, 2011.
The U.S. Environmental Protection Agency Office of Resource Conservation and Recovery has initiated the review and validation process for four leaching tests under consideration for inclusion into SW-846: Method 1313 "Liquid-Solid Partitioning as a Function of Extract pH for Constituents in Solid Materials using a Parallel Batch Extraction Procedure" Method 1314 "Liquid-Solid Partitioning as a Function of Liquid-Solid Ratio for Constituents in Solid Materials using an Up-flow Percolation Column Procedure" Method 1315 "Mass Transfer Rates of Constituents in Monolithic or Compacted Granular Materials using a Semi-dynamic Tank Leaching Procedure" Method 1316 "Liquid-Solid Partitioning as a Function of Liquid-Solid Ratio for Constituents in Solid Materials using a Parallel Batch Extraction Procedure" These protocols are derived from published leaching methods contained in the Leaching Environmental Assessment Framework (LEAF), an integrated set of testing methods, data management tools, and report support. The methods comprise a suite of available leaching tests, including batch, column and tank tests, which may be interpreted individually or integrated to provide characteristic leaching behavior of a solid material over a range of potential release scenarios. LEAF also includes tools for visualizing leaching data and significantly facilitating data management through the LeachXS Lite expert leaching system software program. LEAF represents a considerable shift in leaching assessment methodology from current approaches which are typically based on single-point pH tests and not necessarily reflective of management conditions. Thus, this document provides the required background necessary to understand the development, application, and use of these four test methods. The document includes sections on an overview of the leaching process, selection of test parameters, and estimates of the time, material and costs required.