Ecosystems Research Division

Biographical Information

Name: Christopher D. Knightes
Title: Environmental Engineer

Contact Info:
US EPA National Exposure Research Laboratory

Athens, Georgia 30605

Phone:
(706) 355-8326

E-mail:
Knightes.Chris@epa.gov

Education:

Ph.D., Civil and Environmental Engineering (Environmental Engineering and Water Resources), Princeton University, 2000
M.A., Civil Engineering and Operations Research (Environmental Engineering and Water Resources), Princeton University, 1997
M.S., Civil Engineering (Environmental Health Engineering), Northwestern University, 1995
B.S., Physics, University of Rochester, 1992

Expertise/Research Interests:

• Fate and Transport of Environmental Contaminants with particular emphasis on physical, chemical, and biological processes
• Numerical Modeling of Complex Systems: Multi-component and Multi-media (watershed, water body, sediment, ground water)
• Environmental Microbiology, particularly with respect to microbial transformations of environmental compounds
• Risk and Exposure Assessment
• Environmental Chemistry, particularly chemistry of complex mixtures

Previous Experience:

Publications:

1. Brown, S., Saito, L., Knightes, C.D., Gustin, M. 2007. Calibration and Evaluation of a Mercury Model for a Western Stream and Constructed Wetland. Accepted to appear in Water, Air, & Soil Pollution.

2. Knightes, C.D., Ambrose, R.B., Jr. 2007. Evaluating Regional Predictive Capacity of a Process-Based Mercury Exposure Model, Regional-Mercury Cycling Model, Applied to 91 Vermont and New Hampshire Lakes and Ponds, USA . Environmental Toxicology & Chemistry. 26( 4).

3. Knightes, C.D., Peters, C.A. 2006. Multi-Substrate Biodegradation Kinetics for Binary and Complex Mixtures of Polycyclic Aromatic Hydrocarbons. Environmental Toxicology & Chemistry. 25(7):1746-1756.

4. Knightes, C.D., Cyterski, M. 2005. Evaluating Predictive Errors of a Complex Environmental Model using a General Linear Model and Least Square Means. Ecological Modelling. 186(3):366-374.

5. Knightes, C.D., Peters, C.A. 2003. Aqueous Biodegradation Kinetics of 10 PAH Compounds. Environmental Engineering Science. 20(3):207-218.

6. Knightes, C. D., Peters, C. A. 2000. A Statistical Analysis of Nonlinear Parameter Estimation for Monod Biodegradation Kinetics Using Bivariate Data. Biotechnology and Bioengineering, 69(2):160-170.

7. Peters, C. A., Wammer, K. M., Knightes, C. D. 2000. Multicomponent NAPL Solidification Thermodynamics. Journal of Transport in Porous Media. 38(1-2):57-77.

8. Knightes, C. D. and C. A. Peters.2000. Substrate Interactions in the Biodegradation Kinetics of PAH Mixtures. American Chemical Society, ENVR, Preprints of Extended Abstracts. Vol. 40. No. 1.

9. Brown, D. G., Knightes, C. D., Peters, C. A. 1999. Risk Assessment for Polycyclic Aromatic Hydrocarbon NAPLs Using Component Fractions. Environmental Science and Technology, 33(24): 4357-4363, 1999.

10. Peters, C. A., Knightes, C. D., Brown, D. G. 1999. Long-Term Composition Dynamics of PAH-Containing NAPLs and Implications for Risk Assessment. Environmental Science and Technology, 33(24): 4499-4507.

11. Knightes, C. D., C. A. Peters. 1999. "Measurement and Comparison of Monod Biodegradation Parameters of PAHs". In: A. Leeson and B. C. Alleman (Eds.), Bioremediation Technologies for Polycyclic Aromatic Hydrocarbon Compounds. Battelle Press, Columbus, OH. pp. 173-178.

12. Hansen, K. M., C. D. Knightes, C. A. Peters. 1998. "Multicomponent NAPL Solidification Thermodynamics". Proc. 1998 Symposium on Environmental Models and Experiments Envisioning Tomorrow (EnviroMEET'98): Behavior and Remediation of Nonaqueous Phase Contaminants in the Subsurface. July 20-23, 1998. Irvine, CA. pp. 113-124.

13. Peters, C. A., Mukherji, S., Knightes, C. D., Weber, W. J., Jr. 1997. Phase Stability of Multicomponent NAPLs Containing PAHs. Environmental Science and Technology, 31(9): 2540-2546.

14. Peters, C. A., P. A. Labieniec, and C. D. Knightes. 1996. "Multicomponent NAPL Composition Dynamics and Risk". Proc. ASCE Annual Convention: Non-Aqueous Phase Liquids (NAPLs) in the Subsurface Environment: Assessment and Remediation. (Peer-Reviewed) L. N. Reddi, Ed. Washington, DC, Nov. 1996, pp. 681-692.

15. Knightes, C. D. and C. A. Peters. 1996. "Numerical Simulation of Multicomponent NAPL Dissolution and Precipitation". WEFTEC'96, Proc. Water Environment Federation 69th Annual Conference, Dallas, TX, Oct 5-9, 1996. Vol. I, Part I: Wastewater Treatment Research, pp. 333-343.

Selected Presentations:

1. Ambrose, R.B., Jr., Knightes, C.D., Rashleigh, B. 2007. Toxics in our Rivers. Presented at the Georgia River Network Conference 2007 "Ensuring a Clean Water Legacy." Milledgeville, GA. February 17.

2. Knightes, C.D. 2006. Evaluating the Regional Predictive Capacity of a Process-Based Mercury Exposure Model (R-MCM) for Lakes across Vermont and New Hampshire, USA . Presented at the Society of Environmental Toxicology and Chemistry (SETAC) 27^th Annual Meeting. Montréal, Québec, Canada , November 5 - 9.

3. Ambrose, R.B., Jr., Knightes, C.D., Wool, T.A., Dai, T., Alvi, K. 2006. Modeling Processes Controlling Mercury Fate in Watersheds Receiving Atmospheric Deposition -- Case Study using Watershed Scale WCS-GBMM. Presented at the Eighth International Conference on Mercury As a Global Pollutant, Madison, WI, August 6-11.

4. Ambrose, R.B., Jr., Wool, T.A., Knightes, C.D. 2006. Modeling Mercury Dynamics in Stream Systems with WASP7: Characterizing Processes Controlling Short and Long Term Response. Presented at the Eighth International Conference on Mercury As a Global Pollutant, Madison, WI, August 6-11.

5. Knightes, C.D. 2006. Overview of Session Goals with Examples of the Evolution of Multi-Media Modeling for Informing Regulatory Decisions at the U.S. Environmental Protection Agency. Presented at the Eighth International Conference on Mercury As a Global Pollutant, Madison, WI, August 6-11.

6. Knightes, C.D. 2006. Development and Test Application of SERAFM: A Screening-Level Mercury Fate Model and Tool to Assist Risk Assessors in Evaluating Wildlife Exposure Risk for Aquatic Ecocystems with Mercury Contaminated Sediments. Presented to the USEPA's ORD/NERL/ERD Seminar Series. Athens, GA. May 25.

7. Brown, S., Saito, L., Knightes, C., Gustin, M. 2006. Modeling Mercury Behavior in a Contaminated Desert Stream and Constructed Wetland. Presented to the Nevada Water Resources Association. Las Vegas, NV. February 21 - 23.

8. Knightes, C.D. 2005. Development and Application of a Tool for Evaluating Wildlife Exposure Risk Associated with Mercury-Contaminated Sediments. Presented at the Society of Environmental Toxicology and Chemistry (SETAC) 26^th Annual Meeting. Baltimore, Maryland, USA , November 13 - 17.

9. Sunderland, E., Knightes, C., Ambrose, R., Johnston, J. 2005. Modeling the Response of a Variety of Freshwater Ecosystems across the United States to Changes in Atmospheric Mercury Deposition Associated with the Clean Air Mercury Rule. Presented at the Society of Environmental Toxicology and Chemistry (SETAC) 26^th Annual Meeting. Baltimore, Maryland, USA , November 13 - 17.

10. Knightes, C.D., Ambrose, R.B., Jr. 2005. Understanding the Transport and Fate of Globally Relevant Environmental Pollutants: The Mercury Example. Presented to Emory University's Department of Global Health 2005 - 2006 Wednesdays' Seminar Series. Atlanta, GA. September 14.

11. Ambrose, R.B., Jr., Johnston, J.M., Knightes, C.D., Sunderland, E. 2005. Tying it All Together: EPA Field Studies and Models Used in the Clean Air Mercury Rule. Presented at EPA Science Forum 2005, Washington, DC, May 16 - 18.

12. Knightes, C.D. 2005. SERAFM: An Ecological Risk Assessment Tool for Evaluating Wildlife Exposure Risk Associated with Mercury-Contaminated Sediment in Lake and River Systems. Presented at EPA Science Forum 2005, Washington, DC, May 16 - 18.

13. Johnston, J.M., Hoff, D., Knightes, C., Ambrose, Jr., R.B., Ducheneaux, C., and Hoogerheide, R. 2004. Protecting Human Health and the Environment on Sioux Tribal Lands: A Partnership of EPA and Tribal EPD. Presented at: EPA Science Forum 2004, Washington, DC, June 1 - 3.

14. Knightes, C. D., Peters, C. A. 2000. Modeling Multi-Substrate Biodegradation Kinetics of PAH Mixtures. Hazardous Waster Research 2000 Conference, Denver, CO. May.

Government Reports

1. Knightes, C.D. and R. B. Ambrose. 2006. Development of An Ecological Risk Assessment Methodology for Assessing Wildlife Exposure Risk Associated With Mercury-Contaminated Sediments in Lake and River Systems. U.S. Environmental Protection Agency, Athens, GA. Publication No. EPA/600/R-06/073. (PDF, 80 pp., 424 KB).

2. Contributing author to Chapter 3: Ecosystem Scale Modeling for Mercury Benefits Analysis and Appendix A in: Regulatory Impact Analysis for the Clean Air Mercury Rule. 2005. Office of Air Quality Planning and Standards. EPA-452-/R-05-003. National Exposure Research Laboratory. Office of Research and Development. US EPA.

3. Knightes, C.D., Ambrose, R.B., Jr. 2004. Analysis of Mercury in Vermont and New Hampshire Lakes: Evaluation of the Regional Mercury Cycling Model. U.S. Athens, GA. Publication No. EPA/600/R-04/080. National Exposure Research Laboratory. Office of Research and Development. US EPA.

Technical Reports

1. ENVIRON. 2002. White Paper: Applications of the Proposed HARS-Specific Values for PCBs In Evaluating Test Results on U.S. Gypsum Dredged Material. Prepared for United States Gypsum Company,

2. ENVIRON. 2002. Risk Evaluation: Former Rodriguez Service Station Site, Barranquitas, Puerto Rico. Prepared for ESSO Standard Oil of Puerto Rico.

3. ENVIRON. 2002. Risk of Remedy Implementation: Former Rodriguez Service Station Site, Barranquitas, Puerto Rico. Prepared for ESSO Standard Oil of Puerto Rico.