Environmental Characterization of Underwater Munitions Constituents at a Former Military Training Range

Abstract

As a result of military activities, unexploded ordnance and discarded military munitions are present in underwater environments, which has resulted in the release of munitions constituents including the high explosives 2,4,6‐trinitrotoluene (TNT) and hexahydro‐1,3,5‐trinitro‐1,3,5‐triazine (RDX), along with their primary degradation products, to the water column and adjacent sediments. The present study focused on the characterization of underwater exposure and concentrations of energetics such as TNT and RDX at the former Vieques Naval Training Range at Bahia Salina del Sur (Vieques, Puerto Rico, USA), a bay with documented high incidence of munitions. In situ passive sampling using polar organic chemical integrative samplers (POCIS) was used for the detection and quantification of constituents in water at target locations approximately 15 to 30 cm from 15 individual potentially leaking munitions, and also at 15 unbiased locations approximately evenly spaced across the Bay. For comparison with POCIS‐derived concentrations, grab samples were taken at the POCIS target locations. The POCIS‐derived and averaged grab samples agreed within a factor of 3. When detected, munitions constituent concentrations (primarily TNT and RDX) were observed at ultratrace concentrations (as low as 4 ng/L for RDX), except 30 cm from one General Purpose bomb where the TNT concentration was 5.3 µg/L, indicating that low‐level contamination exists at Bahia Salina del Sur on a very localized scale despite the relatively high density of munitions, similar to previously reported results for other munitions sites around the world. Sediment and porewater sampled at 4 stations where munitions constituents were detected in the water column had concentrations below detection (approximately 5 µg/kg and 5 ng/L, respectively), suggesting that the sediment was not a sink for these constituents at those locations. Environ Toxicol Chem 2022;41:275–286. © 2021 SETAC. This article has been contributed to by US Government employees and their work is in the public domain in the USA.

Long-Term Trends for Blue Mussels from the German Environmental Specimen Bank Show First Evidence of Munition Contaminants Uptake

“…The parent substance TNT was not detected in any of the mussel samples obtained from the German ESB. However, its metabolites 2-and 4-ADNT were present in the animals, which may have been formed by mussel-specific metabolic enzymes, by microorganisms living in the soft body or on the mussel shells, or in the surrounding sea water [27,34]. In recent field experiments, 2-and 4-ADNT were the predominant metabolites found in exposed blue mussels, with 4-ADNT in significantly higher amounts than 2-ADNT [18,28,29].…”

“…TNT, its metabolites, and other common energetic compounds have been detected in water, sediment, and biota adjacent to sea-dumped munitions [23][24][25][26] and in water and sediment samples from a former military shooting range [27]. Recently, a biomonitoring study with blue mussels (Mytilus spp.)…”

Release of Ammunition-Related Compounds from a Dutch Marine Dump Site

“…Numerous studies have measured munitions compounds like 2,4,6-TNT, 1,3,5-trinitro-1,3,5-triazinane (RDX), octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX), and others in seawater, sediments, and marine organisms (reviewed in [ 17 , 22 , 23 , 24 , 25 , 26 ]). Rosen et al [ 27 ] investigated underwater concentrations of energetics such as TNT and RDX at the former Vieques Naval Training Range at Bahia Salina del Sur (Vieques, Puerto Rico, USA), a bay with documented high incidence of munitions. While, with passive sampling systems, TNT and RDX were observed at ultra-trace concentrations, in sediment and porewater samples munitions constituents were below detection limits (approximately 5 µg/kg and 5 ng/L, respectively).…”

Batch and column tests study on coexistence of TNT and aniline enhancing their Transports in Chinese loess

“…There is a puzzle about the contribution of adsorption. For example, military training ranges pollution resulted mainly from incomplete detonation of munitions, which are typically formulated in combinations of two or more compounds, including 2,4,6-trinitrotoluene (TNT), hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) and octahydro-1,3,57-tetranitro-1,3,5,7tetrazocine (HMX), had led to migration of these compounds into groundwater (Cattaneo et al, 2000;Craig and Taylor, 2011;Rosen et al, 2022). Although TNT has been found in groundwater at other munitions production sites (Spalding and Fulton, 1988;Alavi et al, 2017), much of the TNT contamination remains at or near the soil surface at the Nebraska Ordnance Plant, thus TNT concentrations and its plumes are smaller than that associated RDX in the studied groundwater (Spalding and Fulton, 1988).…”