Bench Scale Fixation of Soils from the Tacoma Tar Pits Superfund Site. Final Report

摘要

The report documents the result of a bench-scale soil fixation study conducted with materials from the Tacoma Tar Pits Superfund Site. Chemical fixation (also called stabilization/solidification) is a relatively new technique for remediating contaminated soils. It entails both immobilization of contaminants via sorption or chemical reaction and physical transformation of the soil into a firm, impervious 'monolith.' Fixation has been used for years to immobilize metals in low-level radioactive wastes and specialized industrial wastes, such as baghouse dusts. It has not been commonly used at sites with organic contamination, however. The study utilized materials contaminated with metals and several types of organic contaminants including benzene, toluene, xylene, polycyclic aromatic hydrocarbons, and polychlorinated biphenyls. Samples of heavily contaminated soils and wastes from the site were chemically fixed using a proprietary product, and the resulting monoliths were subjected to various physical, chemical, and leaching tests. The purpose was to assess the efficacy of fixation for a complicated matrix, i.e., one that was physically heterogeneous and contained several classes of contaminants.