Bioavailability and Biostabilization of PCBs in Soil

EPA Grant Number: R825365
Title: Bioavailability and Biostabilization of PCBs in Soil
Investigators: Luthy, Richard G.
Current Investigators: Luthy, Richard G. , Dzombak, David A. , McNamara, Sean W.
Institution: Carnegie Mellon University
EPA Project Officer: Lasat, Mitch
Project Period: January 1, 1997 through December 31, 1999
Project Amount: $499,056
RFA: DOE/EPA/NSF/ONR Joint Program on Bioremediation (1996) RFA Text |  Recipients Lists
Research Category: Hazardous Waste/Remediation , Land and Waste Management


The research will develop an understanding of the relationship between the bioavailability and biostabilization of polychlorinated biphenyls (PCBs) in aged soils that have undergone active land biotreatment, but which still show a residual concentration. The goal is to advance scientific knowledge for improved estimates of the potential for release of residual PCB congeners, including the concept of biostabilization which envisions that contaminated materials can be actively biotreated to remove a large fraction of the potentially mobile and bioavailable organic contaminants. The key questions to be addressed are: For aged soils that have undergone active land biotreatment, what is the rate of release of residual PCBs? What are the rates of intrinsic biodegradation for residual PCBs and, what are the implications of these factors for environmentally acceptable endpoints and risks for residual PCBs?

This research builds on prior collaborative studies between Carnegie Mellon University and the Aluminum Company of America (Alcoa) on land biotreatment of soil/sludge mixtures contaminated with PCBs and hydraulic oils. The research will take advantage of the significant investment in developing a field site to assess the biodegradation of PCBs in contaminated soil/sludge mixtures. The proposed work will: monitor the transformation and degradation of PCBs in land treatment units during passive operations following active biotreatment; assess the fluxes of water and oxygen in the land treatment units; assess the solubility and release rates of PCBs in the soil/sludge mixtures; develop appropriate models that can be used to identify the key physicochemical and microbial parameters governing the fate of the residual PCBs; and use these results for examining the risk implications of biostabilized PCB contaminants in soil.

The work emphasizes study of aged contaminant mixtures in a field test for which the sequestration of PCBs may render such compounds only slowly available to microorganisms or the environment. The impact of the research will be to link a rational model for bioavailability for aged samples with practical measurements relevant to bioremediation engineering practice. The research will assess the extent that biostabilization reduces risks and uncertainty in risk assessment. To the best of our knowledge, the results that will come from this work are available no where else in the world.

Publications and Presentations:

Publications have been submitted on this project: View all 7 publications for this project

Journal Articles:

Journal Articles have been submitted on this project: View all 3 journal articles for this project

Supplemental Keywords:

Vadose zone, bioremediation, cleanup, environmental chemistry, RFA, Scientific Discipline, Toxics, Waste, Water, Ecosystem Protection/Environmental Exposure & Risk, Bioavailability, Remediation, Chemical Mixtures - Environmental Exposure & Risk, Contaminated Sediments, Environmental Chemistry, Ecosystem/Assessment/Indicators, Ecosystem Protection, exploratory research environmental biology, Chemistry, HAPS, chemical mixtures, Ecological Effects - Environmental Exposure & Risk, Ecological Effects - Human Health, Bioremediation, Biology, Engineering, Ecological Indicators, risk assessment, fate and transport, fate, biostabilization, biostabilization of PCBs, contaminant transport, contaminated sediment, PCBs, biodegradation, hydraulic oils, chemical transport, kinetic studies, land biotreatment, chemical contaminants, bioremediation of soils, contaminants in soil, environmentally acceptable endpoints, models, vadose zone, physicochemical

Relevant Websites: Exit Exit Exit

Progress and Final Reports:

  • 1997 Progress Report
  • 1998 Progress Report
  • Final Report