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USGS · 70171387

RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine) biodegradation in aquifer sediments under manganese-reducing conditions

Paul M. Bradley·Richard S. Dinicola
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Abstract

A shallow, RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine)–contaminated aquifer at Naval Submarine Base Bangor has been characterized as predominantly manganese-reducing, anoxic with local pockets of oxic conditions. The potential contribution of microbial RDX degradation to localized decreases observed in aquifer RDX concentrations was assessed in sediment microcosms amended with [U- 14 C] RDX. Greater than 85% mineralization of 14 C-RDX to 14 CO 2 was observed in aquifer sediment microcosms under native, manganese-reducing, anoxic conditions. Significant increases in the mineralization of 14 C-RDX to 14 CO 2 were observed in anoxic microcosms under NO 3 -amended or Mn(IV)-amended conditions. No evidence of 14 C-RDX biodegradation was observed under oxic conditions. These results indicate that microbial degradation of RDX may contribute to natural attenuation of RDX in manganese-reducing aquifer systems.

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Paul M. Bradley, Richard S. Dinicola. 2005. RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine) biodegradation in aquifer sediments under manganese-reducing conditions. https://doi.org/10.1080/10889860590929574

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