PH05 Fate and Effects of Energetic Compounds
Exhibit Hall
8:00 AM - Thursday
(PH021) Fate and potential exposure associated with 2,4,6-trinitrotoluene (TAT) and hydroxyaminotoluenes in groundwater contaminated with explosives.
Tratnyek, Paul1, Johnson, Richard1, Toccolino, Patricia1, Bae, Bumhan2, 1 Oregon Health & Science University, Portland, OR, 972392 Kyungwon University, Republic of Korea
ABSTRACT- 2,4,6-triaminotoluene (TAT) can form in groundwater from the reduction of 2,4,6-trinitrotoluene (TNT) by microbial or chemical reactions during remediation and possibly as the result of natural attenuation. TAT appears to be stable under strongly reducing conditions (e.g., those present down gradient from iron permeable reactive barriers where low dissolved oxygen, high pH, and low natural organic matter conditions are present.) Under these conditions TAT will be transported in the subsurface. However, TAT is very labile to a number of transformations (hydrolysis, autooxidation, coupling) under less reducing conditions (i.e., moderate pH where dissolved oxygen, and natural organic matter are present). Therefore, we expect that under most circumstances, TAT will eventually be transformed in the subsurface. Laboratory studies indicate that likely TAT reaction products are mono- and dihydroxyaminotoluenes (HATs) and potentially trihydroxytoluene. Little is known of the environmental fate of these compounds. This is the case, in part, because analytical methods capable of detecting these compounds at environmentally relevant concentrations are not available. Both human and ecological receptors are potentially exposed to TAT and its transformation products via removal of groundwater for public-water supplies and/or discharge through sediments to surface-water bodies. Therefore, it is important to understand the transport and fate of these contaminants in groundwater. Laboratory investigations to improve analytical methods and examine the reactivity of the compounds are currently underway. These will compliment ongoing field investigations to examine the presence, persistence and transport of these compounds in the subsurface.
Key words: groundwater, TNT, transport and fate