TY - JOUR A1 - Lopez Meza, Sarynna A1 - van der Sloot, H. A1 - Kosson, D.S. T1 - The effects of intermittent unsaturated wetting on the release of constituents from construction demolition debris JF - Environmental engineering science N2 - When used in highway applications, granular materials are submitted to changing environmental conditions. While column testing can provide a closer approximation to field percolation conditions than batch testing, there is still a need to develop column testing procedures that more closely approximate realistic conditions. Current column studies are conducted under continuously saturated conditions, without considering unsaturated intermittent flow conditions that exist in the field in response to precipitation events. This study evaluates the effect of different types of column flow on the release of constituents from a granular material. Two different types of intermittent unsaturated flow were studied and compared to continuously saturated flow. Leaching data, including pH, conductivity, and constituent release was compared from the three types of columns. Results showed that there is no difference between the two types of intermittent unsaturated flow, nor is there a significant difference between these two flows and continuously saturated flow, other than higher initial concentrations of salts in intermittent unsaturated flow column testing at low LS ratios. However, this difference is not significant after a LS ratio of 2mL/g. Release of constituents was similar in all three cases. Also, all three cases show that after a LS ratio of 5mL/g there is no significant change in the pH, conductivity or release of constituents. KW - Intermittent flow KW - Column tests KW - Leaching PY - 2009 DO - https://doi.org/10.1089/ees.2007.0337 SN - 1092-8758 SN - 1557-9018 VL - 26 IS - 3 SP - 463 EP - 469 PB - Liebert CY - Larchmont, NY AN - OPUS4-20933 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -