Faculty and Staff Willie F. Harper, Jr.

Associate Professor, Department of Civil and Environmental Engineering Email: wfh3@pitt.edu Phone: (412) 624-9548 Fax: (412) 624-0135

Education

• Ph.D., Civil and Environmental Engineering, University of California, Berkeley (2002).
• M.Eng., Civil and Environmental Engineering, Cornell University (1993).
• B.S., Civil Engineering, University of California, Los Angeles (1992).

Current Research

The Harper Research Group is interested in biological processes for environmental engineering. This includes engineered systems, such as biological wastewater treatment processes, and also natural systems such as wetlands and estuaries. Our research combines traditional approaches, such as mathematical modeling and laboratory-scale experimentation, with the modern tools from bio- and organic chemistry, including enzyme assays, NMR, and thin layer chromatography. Research based on this combination uncovers knowledge and provides exciting opportunities for interdisciplinary collaboration. Although individual projects might emphasize experimentation, modeling, or microbiological aspects, all research involves quantification, the key to making the research results relevant to engineers. The ongoing research fits within two themes, emerging water contaminant issues and microbial storage polymer metabolism.

The emerging water contaminants that are currently being studied include (among others) synthetic steroids and antibiotics. The overall goal in this area is to improve understanding of the basic underlying mechanisms governing their fate and transport. These research results are expected to be an important part of the foundation needed for understanding environmental fate of emerging water contaminants. Previous results by the PI and others place our technical community in position to provide critical and missing information related to biodegradation and sorption of emerging water contaminants. With respect to biodegradation, our research group is studying the biotransformation of numerous natural and synthetic compounds. With respect to sorption, our work is defining the fundamental thermodynamic parameters and is also uncovering a key connection between particle characteristics and sorption hysteresis.

The microbial storage polymer work has focused on the metabolism of polyphosphate, glycogen, and exocellular polymeric substances. The metabolism of these polymers is important in biological processes, and is related to the dynamic growth conditions encountered by microorganisms as they compete for substrate, nutrients, and space. The study of polyphosphate metabolism has particularly broad appeal, because inorganic polyphosphate is essential for long-term survival and virulence factors of many human pathogens and other microbial species growing in extreme environments.

Current and Recent Research Sponsors

• National Science Foundation (CAREER award and unsolicited research programs)
• Environmental Protection Agency: Science to Achieve Results Program
• United States Geological Survey

Professional Certification

• Registered Professional Engineer (Environmental), Arizona.
• OSHA 40-hr HAZWOPER Certification.

Recent Publications

• Yi, T. and Harper, Jr., W.F. (2007). The link between nitrification and biotransformation of ethinylestradiol, Environ. Sci. Tech., 41(12): 4311-4316.
• Yi, T. and Harper, Jr., W.F. (2007). The effect of biomass particle characteristics on the partitioning and sorption hysteresis of ethinylestradiol, Water Research, 41(7): 1543-1553.
• Xiong, Z, Zhao, D., and Harper, W.F. (2007). Sorption and Desorption of Perchlorate with Various Classes of Ion-Exchangers: A Comparative Study, Industrial and Engineering Chemistry, 46 (26), 9213 -9222.
• Robert Waters, Erin Carroll, Andrew Land, Mustafa Mazher, Larissa Parsley, Willie F. Harper, Jr., PhD and Mark R. Liles, PhD. Phylogeny of and Antibiotic Resistance in Activated Sludge and Bioreactor Microbial Communities, Florida Branch of the American Society for Microbiology Regional Conference, St. Petersburg, FL., March 2007.
• Yi, T., Harper, Jr., W.F. , Holbrook, R.D., and Love, N.G. (2006). The role of particle size and nitrification in removal of ethinylestradiol in bioreactors. ASCE J. Env. Eng., 132(11): 1527-1529.
• Harper, Jr., W.F., Anise, O., and Brown, E. (2006). Polyphosphate buffering by biomass with different phosphorus contents. Water Research, 40(8):1599-1606.
• Harper, Jr., W.F., Bernhart, M., and Newfield, C. (2006). Membrane bioreactor biomass characteristics and microbial yield at very low mean cell residence time. Water SA, 32(2):193-198.

Recent Invited Presentations

• Aga, D.S. and Harper Jr., W.F. Investigating the connection between nitrification and the removal of ethinylestradiol, iopromide, and trimethoprim in engineered bioreactors. Micropol and Ecohazard, 2007, Frankfurt, Germany.
• Harper, Jr., W.F., Sorption and biotransformation of PPCPs in biological treatment systems, Virginia Polytechnic and State University ,Department of Environmental Engineering Seminar, Blacksburg, VA, December 2006.
• Harper, Jr., W.F., Enhanced biological phosphorus removal for industrial wastewater treatment, "77th Annual Water Environment Federation Technical Exposition and Conference; Workshop #122, Strategies for achieving low levels of nutrients in wastewater effluents", New Orleans, LA, October 2004.
• Harper, Jr., W.F., Application of the anaerobic/aerobic process for treatment of phosphorus-deficient wastewater, 76th Annual Water Environment Federation Technical Exposition and Conference, Chicago, Ill., October 2003.
• Harper, Jr., W.F., Anaerobic/anaerobic suspended growth technology, Northwestern University Minority Lecturer Series, Evanston, Ill., June 2003.