Bioremediation of explosives-contaminated soil using microbial and environmental enhancements: a field-simulated...

This pilot study evaluated a field-simulated bioremediation treatment for soils contaminated with military explosives as a precursor to a planned large-scale cleanup (~ 7,000,000 m²) in Israel. Sandy-loam soil was amended with compost and a microbial and managed under controlled irrigation and aeration for 85 days. HPLC analyzed six sampling rounds collected at defined intervals. Temporal changes in RDX, HMX, and TNT, commonly found at military sites and posing risks to human and environmental health, were assessed with LMMS and start-vs-end comparisons with non-parametric tests. Initial mean concentrations were 120.46 ± 34.54 mg kg⁻¹ (RDX), 144.73 ± 36.95 mg kg⁻¹ (TNT), and < LOQ for HMX. RDX and TNT declined sharply from day 55 onward and remained at or near non-detectable levels through day 85 (GLMM contrasts, all p < 0.001 after day 55); start-to-end differences corroborated these reductions (RDX: W = 12, p = 0.050; TNT: W = 12, p = 0.0319). HMX exhibited a non-monotonic pattern, increasing at day 40 (mean 4.66 ± 1.06 mg kg⁻¹) and decreasing thereafter, with a small residual at day 85 (0.12 ± 0.25 mg kg⁻¹; start-to-end W = 0.01, p = 0.0436). Overall, under field-simulated conditions, the treatment rapidly and sustainably reduced RDX and TNT. However, HMX showed greater variability and may require extended treatment or complementary measures. These quantitative pilot results inform the design and risk management of forthcoming full-scale remediation in similar semi-arid settings.