Dissolution Rate, Weathering Mechanics, and Friability of TNT, Comp B, Tritonal, and Octol

Abstract : The Army needs live-fire training and testing, but residues from such activity can contaminate nearby groundwater and trigger regulatory actions that restrict training or even close bases. Our three-year project measured the dissolution of TNT, Comp B, Tritonal, Octol, and C4, both in the laboratory and outdoors under conditions that mimic what occurs in the field-dissolution of spatially isolated explosives scattered onto range soils. The resulting data and dissolution models provided insight on environmental factors that affect dissolution, the frequency at which explosive chunks split, and the size of explosive loads on existing ranges. Our drop-impingement model indicated we can use rainfall data and average solubility to calculate the dissolution rate and expected lifespan of explosive pieces. Other findings included learning that the crushing strengths of explosives were low and did not significantly change after three years of outdoor exposure. Also, size distributions of the crushed explosives showed power law distributions, as found for blow-in-place, low-order detonations. This similarity suggests that we can crudely estimate particle size distributions on soils from total mass. Range managers can use the work reported here to guide future training and cleanup activities.