Current models for predicting the environmental fate of munitions constituents (MC) in soils are based mostly on chemical distribution parameters and neglect the larger considerations of other soil parameters. We are working towards a new approach based on the whole soil activity for predicting the long-term residence time and fate of MC in soils with connection to agronomic soil fertility concepts. These relationships are demonstrated by correlating experiments involving full physical and chemical characterization of eight taxonomically distinct soils, with batch reactor studies determining MC degradation potential. Soils were incubated in a slurry for 10 days in a closed reactor system with temperature, pH, and Eh readings recorded every 24 h. Air and slurry samples were taken eight times within the 168 h incubation period. Carbon dioxide, TNT, and nutrient solution concentrations were assessed to obtain a full picture of soil chemistry changes associated with microbial activity in response to additions of TNT. Multivariate analysis was used to determine the main factors impacting degradation rate. Principle Components Analysis (PCA) statistically classified the soils based on the variance of their soil property data. Partial Least Squares Analysis (PLS) showed that TNT degradation was possibly correlated with soil fertility characteristics. Although this is an exploratory study, results show promise in moving towards a more effective way of predicting TNT environmental fate in soils.

Methods for rapid, safe and effective detection of unmapped buried ordnance are vital to the protection of humans and environmental quality throughout the world. This study aimed to investigate the use of phytosensing and to understand the physiological response of woody plants to 2,4,6-trinitrotoluene (TNT) contamination. Baccharis halimifolia were potted in soils containing various concentrations of TNT and physiological responses were observed over a 9-week experimental period. Measurements included the collection of remotely sensed data, such as hyperspectral reflectance and chlorophyll fluorescence, and traditional plant-level physiological data. In accordance with the hypothesis, low levels of TNT improved physiological response in plants due to the slight increase in nitrogen, while high levels of TNT induced stress. Key markers in stress responses were identified, specifically with reflectance indices and derivatives, which may separate TNT-contaminated plants from naturally stressed plants and would allow for accurate detection of buried ordnance at the landscape level.

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This Diploma Thesis is focused on study of electrochemical behavior of 2,4,6-trinitrotoluene (TNT) and 2,4,6-trinitrophenol (picric acid) on finding the optimum conditions for their determination using direct current voltammetry (DCV) and differential pulse voltammetry (DPV) at a mercury meniscus modified silver solid amalgam electrode (m-AgSAE) in the solution of Britton-Robinson (BR) and on finding of the limit of quantification (LQ) for these substances. Practical applicability of the newly developed methods was verified on direct determination of TNT and picric acid in model samples of drinking and river water. Moreover, the electrochemical behaviors of TNT and picric acid was studied using cyclic voltammetry (CV). Optimum medium for the determination of TNT at m-AgSAE was: methanol-BR buffer pH 4.0 (1:9). Upon the DCV it is proper to apply regeneration potentials Ereg,1= 0 mV and Ereg,2= -1100 mV and upon the DPV was apply regeneration potentials Ereg,1= 0 mV and Ereg,2= -600 mV were applied. The concentration dependence of the peak current was found to be linear for both techniques over the concentration range of 1·10-6 -1·10-4 mol/l with LQ of 0.54 µmol/l (for DCV) and 0.46 µmol/l (for DPV). The method developed for the determination of TNT were verified on the model samples of drinking...