Fate and Transport of Energetics from Surface Soils to Groundwater

The principal energetic compounds found at military ranges include hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX), and perchlorate. These are found in rocket, artillery, grenade, and mortar Impact Areas as well as Open Burn/Open Detonation (OB/OD) and Explosive and Ordnance Disposal (EOD) sites. RDX, HMX, and perchlorate are persistent and mobile in aerobic aquatic environments with the primary fate-and-transport mechanisms being advection, dispersion, and dilution. Other compounds frequently detected in soil but less frequently in groundwater include 2-amino-4,6-dinitrotoluene (2a-DNT), 4-amino-2,6-dinitrotoluene (4a-DNT), 2,4-dintrotoulene (2,4-DNT), 2,6-dinitrotoluene (2,6-DNT), nitroglycerin (NG), and 2,4,6-trinitrotoluene (TNT). These compounds are more susceptible to phototransformation, biotransformation, and adsorption than HMX, RDX, and perchlorate, and with the exception of TNT, are typically released in much smaller amounts. TNT and the amino-DNTs are typically found in Impact Areas, OB/OD, and EOD sites. In contrast, DNTs and NG are found principally at artillery and mortar and small arms firing positions while NG is most common at anti-tank rocket firing positions.