PRELIMINARY-RESULTS FROM A FIELD EXPERIMENT INVESTIGATING THE FATE OFSOME CREOSOTE COMPONENTS IN A NATURAL AQUIFER

Creosote, a distillation product of coal tar, is made up of an extreme ly complex mixture of phenols and polycyclic aromatic compounds (PAC) which include polycyclic aromatic hydrocarbons (PAH) and nitrogen, sul phur and oxygen (NSO) containing heterocyclics. It is considered to be an environmental hazard. This report presents some preliminary result s from a large field experiment that is evaluating the mobility, persi stence and fate in groundwater of compounds present in coal tar creoso te. This involved setting up a long-term field experiment where a limi ted plume of contaminated ground water was created by placing creosote into an extremely well characterized sand aquifer. The original creos ote was dominated by PAH components with minor amounts of NSO containi ng PAC. The concentration of the dominant nitrogen heterocyclic (quino line) was only 10% of the abundance of the major PAH components (napht halene and phenanthrene). Analysis of groundwater samples collected 27 8 days after the emplacement of the creosote shows that with increasin g distance from the source the concentration of naphthalene is reduced while that of quinoline increases, eventually becoming dominant. A si milar trend was also observed for samples collected after 471 days and this can be related to the relative aqueous solubilities and mobility of the two compounds. Also observed in the outermost 471 day samples was the presence of quinolinone which is believed to be an aerobic met abolite of quinoline. Strategies for the final parr of the project whi ch involve cleaning up the Borden experimental site are briefly discus sed in light of these results.