Geoenvironmental Characterization to Assess Waste Stabilization/Solidification Treatment Performance and Sustainability: Fid-Bau Portal

Geoenvironmental Characterization to Assess Waste Stabilization/Solidification Treatment Performance and Sustainability

Dermatas, Dimitris / Chrysochoou, Maria / Moon, Deok Hyun

Stabilized/Solidified (S/S) waste, whether a contaminated soil, sediment or industrial waste, is usually evaluated on the sole basis of regulatory leaching tests. These tests provide point-in-time performance data and cannot alone provide a solid foundation for a reliable assessment of long term performance and overall treatment sustainability. Instead, the use of state-of-the-art geoenvironmental characterization techniques constitutes a more reliable approach to effectively evaluate S/S treatment alternatives and develop a sustainable S/S treatment design and field implementation. This involves a combination of traditional geotechnical analyses (particle size distribution, unit weight, water content), physicochemical analyses (pH, total metal contents), a subset of controlled pH extraction tests (Toxicity Characteristic Leaching Procedure, TCLP, Synthetic Precipitation Leaching Procedure, SPLP, etc.) coupled with non-destructive quantitative mineralogical analyses (X-ray Powder Diffraction, XRPD combined with Rietveld Quantitative Analysis, RQA). Additionally, micromorphological (Scanning Electron Microscopy-Energy Dispersive Spectroscopy, SEM-EDS and/or Electron Probe Micro-Analysis, EPMA) and other contaminant speciation analyses (X-Ray Absorption Near-Edge Spectroscopy, XANES and/or Extended X-ray Absorption Fine Structure, EXAFS or other newly developed techniques) should be used once a more in-depth assessment is required. In this paper a general framework along with case studies involving such state-of-the-art geoenvironmental characterization of Pb and hexavalent Cr(VI) contaminated, stabilized waste are presented.