1 / 9

Environmental Decay Pathways of the Chemicals of Concern (COCs)

Environmental Decay Pathways of the Chemicals of Concern (COCs). Soil Concentrations of Contaminants. Contaminant. Average Concentration of Detections (  g/kg). No. Detects/No. Total Samples. Maximum Concentration (  g/kg). Clean-up Goal (  g/kg). RDX. 4,000. 37/123. 40,000. 120.

hewitt
Download Presentation

Environmental Decay Pathways of the Chemicals of Concern (COCs)

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Environmental Decay Pathways of the Chemicals of Concern (COCs)

  2. Soil Concentrations of Contaminants Contaminant AverageConcentration of Detections (g/kg) No. Detects/No. Total Samples Maximum Concentration (g/kg) Clean-up Goal(g/kg) RDX 4,000 37/123 40,000 120 HMX 1,000 30/123 8,000 250 TNT 170 1/123 170 250 2,4-DNT 79 1/8 79 700 2A-DNT 207 12/123 550 1,240 4A-DNT 180 4/123 260 330 Nitroglycerin (NG) 3,200 1/123 3,200 2,500

  3. Characteristics of COCs • RDX-Royal Demolition Explosive (1,3,5-trinitro-1,3,5-triazacyclohexane) • Military explosive • Toxic to humans & mammals-carcinogen • HMX-High Melting Explosive (1,3,5,7-tetranitro-1,3,5,7-tetrazacyclooctane) • Impurity resulting from RDX production • Associated systemic poisoning (marrow & liver)

  4. Fate and Transport: • Biological Decay • Aerobic/Anaerobic • Abiotic Decay • UV • Adsorption • Reversible/Irreversible • Transport • How do pH/Temperature affect solubility

  5. Degradation of RDX • Mineralized by White Rot Fungus • Uses RDX as main source of nitrogen • Produces CO2 and N20 • Subcritical Water • RDX starts degrading with 100oC H20 • >99.9% destruction with 275oC H20 • Anaerobic Co-metabolism • Converted to Acetate

  6. Degradation of HMX • UV Radiation Oxidizes HMX • H2O2 as catalyst • Sunlight breaks down HMX in H20 • Subcritical Water • HMX starts degrading with 125oC H20 • >98% destruction with 275oC H20 • Anaerobic Degradation via Reduction • Converted to methanol and chloroform

  7. Transport • RDX solubility- 60mg/L • Low affinity for soil particles • However, sorption is nearly irreversible • HMX- nearly insoluble in H2O • Likely to move into groundwater

  8. Nitroglycerin

  9. Nitroglycerin • Metabolization • P. chrysosporium • Produces di and mono nitrates • G. candidum • Produce glycerol • Transgenic Plants • Metabolize more slowly than microbes

More Related