Hydrated lime for metals immobilization and explosives transformation: Treatability study.

Fragmentation grenades contain Composition B (RDX and TNT) within a steel shell casing. There is the potential for off-site migration of high explosives and metals from hand grenade training ranges by transport in surface water and subsurface transport in leachate. This treatability study used bench-scale columns and mesocosm-scale laboratory lysimeters to investigate the potential of hydrated lime as a soil amendment for in situ remediation of explosives and metals stabilization in hand grenade range soils. Compared to the unamended soil there was a 26-92% reduction of RDX in the leachate and runoff water from the lime treated soils and a 66-83% reduction of zinc in the leachate and runoff water samples; where the hand grenade range metals of concern were zinc, iron, and manganese. The amended soil was maintained at the target pH of greater than 10.5 for optimum explosives decomposition. The treatability study indicated a high potential of success for scale-up to an in situ field study.

An extraction/concentration procedure for analysis of low-level explosives in soils.

The methods traditionally used for explosives analysis in soil matrices have inherent data quality limitations for low-level samples. The traditional methods employ a soil-dilution extraction of the sample prior to analysis by high performance liquid chromatography with UV absorption detection. Another concern with the traditional analysis is that energetics contamination in environmental samples is often very heterogeneous in nature, usually requiring a large number of samples and multiple testing. The technique presented here addresses these data quality limitations by using a concentrative extraction procedure which produces a small volume of extract from a large soil sample. A concentration factor of 60-fold is achieved in this manner and energetics detection limits for soils are lowered by two orders of magnitude. The larger soil sample size also helps reduce the error associated with sample heterogeneity. The ability to detect explosive-based contaminants at levels of environmental interest enables a more accurate assessment of the transport pathways and treatment options for explosives contamination.