Environmental impacts of low and high order detonations in water

The clearance of dumped munitions often relies on low order (LO) and high order (HO) detonation techniques, both of which pose significant risks to aquatic ecosystems. LO detonation leaves behind substantial explosive residues, whereas HO detonation generates intense shock waves and extensive fragmentation. This study examines the environmental impact of these detonation methods, including partial detonation, under semi-controlled conditions using six 1000-litre Intermediate Bulk Container (IBC) tanks. Partial detonation represents an incomplete LO detonation, resulting in the high transfer of TNT to the aquatic environment. Explosive residues were almost 8 times higher after LO detonations (8.7 ± 2.8 mg/L) compared to HO (1.2 ± 0.4 mg/L). Fragmentation analysis revealed that HO produced more than twice the number of fragments compared to LO, increasing the potential for physical damage. By integrating these findings with modelling, the fragment stopping distances were estimated. The maximum distance covered by the fragments ranged between 94.9 and 107.1 m. The acute toxicity spatial extent of explosive contamination from a single World War (WW) munition detonation was found to be 25-40 m (LO); 36-58 m (Partial); 14-23 m (HO). Considering, there are stockpiles of munitions in the water bodies, this distance can be much larger. These insights aid to minimise both chemical and physical environmental impacts, particularly in the context of World War-era munitions clearance.