Project Significance:

Created by George Rice, Montana State University

At the turn of the last Century, municipalities throughout the northeastern U.S. provided street lighting for citizens through lanterns fueled by volatile gases generated by coal gasification plants. Coal tar waste, a black tarry polycyclic aromatic hydrocarbon-rich byproduct, presently is buried near thousands of mostly urban coal gasification sites throughout the region. Because the coal tar waste in South Glens Falls was buried in a hydrogeologically simple setting, this site was chosen as an ideal situation for deciphering complex chemical and microbiological processes that influence the fate of coal tar waste materials. Naphthalene is one of the most abundant and soluble of the coal tar-derived compounds.

The Electric Power Research Institute (EPRI), in conjunction with Niagara Mohawk Power Corp., the site owner, have invested $2.5 million in the site since 1988. The site features 59 monitoring wells, 157 piezometers, 162 soil borings, and 18 multi-level samplers, and ongoing semi-annual groundwater samplings with analyses since 1988. The geology, hydrology, water chemistry, and coal tar contamination are reasonably well understood. The extensive infrastructure, which includes an existing on-site laboratory trailer, provides a well characterized biogeochemical setting for observing microorganisms. 

Diagram conceptually depicting microorganisms and their biogeochemical impact, and Godzilla.

The biochemical, enzymatic, and genetic details of microbial naphthalene degradation have been examined extensively since the early description in 1964 of a naphthalene metabolic pathway in Pseudomonas. Studies of naphthalene degradation are significant for at least four reasons:

  1. Naphthalene's aromatic character poses unique biochemical challenges for enzymatic attack.
  2. Naphthalene is a common pollutant that serves as a chemical model for the degradation of polycyclic aromatic hydrocarbons (PAHs), which are often carcinogenic.
  3. Insights are provided into the behavior of catabolic plasmids, the lateral transfer of genetic information among bacteria, and the evolution of oxygenase genes and enzymes.
  4. Our abilities to effectively manage and treat polluted environments and to engineer novel enzymes for new technologies are increased.

(Wilson et al., 2003, Appl. Environ. Microbiol. 69:2172-2181)

Copyright on all images and material by Eugene L. Madsen, and William C. Ghiorse - 2006.