Soil containing explosive

Ibister JD, Anspach GL, Kitchens JF, Doyle RC (1984) Composting for decontamination of soils containing explosives. Microbiologica 7 47-73... 

The natural organic (humic) content of the soil largely remains after these processes and can be used for successful cultivation. Hydrocarbons are re-precipitated as the water cools, whereas some compounds, such as pesticides, are degraded to less-toxic materials during the extraction process. Soil containing explosives has also been treated in the same pilot plant using static extraction [48]. The destruction of TNT, RDX and HMX was 99.99%, 99.9% and 97.9%, respectively. 

An application well-suited for IMS is the decommissioning and cleanup of sites where extensive manufacturing of explosives has taken place in the last century and where widespread contamination of soils and waters has occurred [74]. Decontamination of model metal scrap artificially contaminated with TNT and of decommissioned mortar rounds stiU containing explosives residue was followed by sampling surfaces with analysis by a portable mobility spectrometer. Mixed anaerobic microbial populations of bioslurries were employed in decontamination of scrap and the mortar rounds, and the IMS analyzer was seen as a sensitive field... 

Nitrogen-containing explosives [249] and trinitrotoluene [250] have been determined in soil by gas chromatography with thermionic NP detection and reverse-phase high-performance liquid chromatography. Warmont et al. [251] used tunable infrared laser detection to study the pyrolysis products of explosives in soil. 

Low Level Waste. The NRC 10CFR61 specifies the nature of the protection required for waste containers (20). Class A wastes must meet minimum standards, including no use of cardboard, wastes must be solidified, have less than 1% Hquid, and not be combustible, corrosive, or explosive. Class B wastes must meet the minimum standards but also have stabiHty, ie, these must retain size and shape under soil weight, and not be influenced by moisture or radiation. Class C wastes must be isolated from a potential inadvertent intmder, ie, one who uses unrestricted land for a home or farm. Institutional control of a disposal faciHty for 100 years after closure is requited. 

Under RCRA. each facility must contain a contingency plan designed to minimize hazards to human hetiltli or tlie enviromiient from fires, explosions, or tuiy unplanned sudden or nonsudden release of hazardous w aste or hazardous waste constituent to air. soil, or surface water. The items tliat follow are applicable to each contingency plan. 

Explosions occurred dining the extraction of fats and waxes from the soils with ether, as well as when heating the extract at 100°C. Although the latter is scarcely surprising (the ether contained 230 ppm of peroxides), the former observation is unusual. 

Of course, the object that contains and releases the explosive can be almost anything. However, since we began this study from the perspective of searching for mines, initially, landmines buried in soil, much of this chapter will use that specific work to illustrate the approach. We have gained a level of understanding for this particular application. From there we can adapt the methods to understand the EF T of molecules in other situations. We can think of numerous examples of other applications where we might need to locate the object that is releasing explosive molecules. 

Summary of Landmine Flux Results Since no one has devised a method of directly measuring the flux of explosive molecules from a mine, whether in situ or in the laboratory, several laboratory measurements have been reported in which the mine was placed in a sealed container, surrounded by soil, water, or air. The concentrations of explosive molecules in the surrounding media were then measured at intervals of several days and the flux inferred from the total concentration divided by the elapsed time. This likely provides the best estimate that can be expected. The various measurements have substantial variation, depending on the techniques and media used. Phelan and Webb describe several experiments [1, pp. 23, 24], It appears that a reasonable expectation of flux of explosive compounds from a buried landmine that move into the surrounding soil will be in the range of 1 to 200 pg/day. There are some complications, of course, since the surrounding soil produces a level of resistance, or back pressure, to the flux of the molecules. While the mechanisms are complex, the net effect is that wet soil permits a lower diffusive flux than dry... 

Dried Puddles Concentrate Molecules In our common experience, we have all observed the formation of puddles after a rain. We realize, without much analysis, that the puddle is not formed from rain that fell in only that location. It contains water that fell nearby and flowed to that area, which is at the locally lowest elevation. If the rain falls on an area that has buried sources of explosive molecules, then some of those that were sorbed to the surface particles above the source will be dissolved and carried into the puddle. When puddles dry they leave a concentration of molecules on the surface soil particles. Thus, an irregularly shaped area of relatively high concentration of molecules may appear some distance from any buried source. See the discussion on Figure 8.2 p 182. 

The size distribution of the radioactive debris containing the majority of the fission products may bear little relationship to the size distribution of the environmental soil. Vaporization, agglomeration, condensation, and coagulation will probably lead to particles smaller than and larger than those found in the soil. A striking demonstration of this is found in the size distribution of radioactive debris of a low yield explosion over an alluvial salt bed in Nevada (6). While the mean diameter of the pre-shot soil particles was about 6/, the prompt fallout contained many intensely radioactive particles of 1000/ or greater. 

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