The Remediation Technology Summit

February 26-28, 2019

Colorado Convention Center
Denver, CO

PeterJaffePeter Jaffe
Professor of Civil and Environmental Engineering
Associate Director for Research, Andlinger Center for Energy and the Environment
Princeton University

Peter Jaffé is a Professor of Civil and Environmental Engineering, and Associate Director for Research at the Andlinger Center for Energy and the Environment, at Princeton University. His background is in chemical engineering, and he obtained a Ph.D. in Environmental Engineering from Vanderbilt University in 1981. He was a faculty member at the Universidad Simón Bolívar in Venezuela from 1983 to 1985 prior to joining the faculty of Civil Engineering at Princeton University in 1985, where he was department chair from 1999 to 2005. He was an AT&T Industrial Ecology Fellow, is an Elected Fellow of the American Geophysical Union, and was appointed as Board Certified Environmental Engineering Member of the American Academy of Environmental Engineers by Eminence.

His research focuses on processes governing the transport and transformation of pollutants in the environment, and their application towards the remediation of contaminated systems. Areas of current emphasis include: (1) simulation and analysis at the watershed scale of nutrient cycling; (2) dynamics of trace metals, radionuclides, and trace organics in sediments, wetland soils, and groundwater; and (3) novel biological processes for anaerobic ammonium oxidation and its applications for water treatment and cometabolic pollutant remediation.

PLATFORM PRESENTER – Biological Treatment: Strength in Small Packages

Exploring Novel Bioremediation Applications Based on the Feammox Process

New insights into the oxidation of ammonium (NH4+) under iron (Fe) reducing conditions, also known as Feammox, indicate the potential of novel bioremediation applications. We have recently isolated and sequenced a bacterium responsible for the Feammox process: Acidimicrobiaceae bacterium A6 (ATCC, PTA-122488) and have been able to show that the pure culture is capable of conducting the Feammox reaction. Isolation of the pure strain has also allowed us to conduct incubations in the presence of different elements and compounds and determine how they are affected, either directly or cometabolically, by the Feammox reaction.

Our own work as well as that by many other investigators reporting Feammox activity at different locations have shown that it is a rather ubiquitous process in acidic, iron rich environments, specially wetlands, hence it is likely that we might be able to stimulate Feammox activity to enhance degradation/immobilization of various elements or compounds of environmental concern, including the oxidation of ammonium. Ongoing mesocosm wetland experiments indicate that wetlands with iron rich soil and seeded with Feammox enrichment cultures remove a significant fraction of influent ammonium via the Feammox process.

Incubations of Acidimicrobiaceae bacterium A6 in the presence of trace quantities of various oxidized elements (i.e. U(VI), Cu(II), Se(VI)) have shown that these elements can serve as electron acceptors and can be reduced simultaneously with Fe(III) when NH4+ is oxidized. Since the solubility of many of these elements can vary with their oxidation state, Feammox might be of interest in their fate and transport as well as insitu remediation.

Analyses from the sequencing of Acidimicrobiaceae bacterium A6 have revealed a novel gene that is related to methane monooxygenases and might be responsible for the oxidation of NH4+. Hence, we have explored the co-metabolic degradation of organic compounds such as chlorinated ethenes and polyaromatic hydrocarbons by Acidimicrobiaceae bacterium A6 during Feammox incubations, and have shown that these compounds can be degraded during these incubations. Interestingly, since Feammox has an optimal pH ~ 4.5, Acidimicrobiaceae bacterium A6 might fill a gap in the groundwater bioremediation industry where bioaugmentation with Rhodococcus sp. for the degradation of chlorinated ethenes is often undertaken but is limited to alkaline conditions. A challenge to conduct effective bioaugmentation with Acidimicrobiaceae bacterium A6 is the production of the required amount of biomass in a reasonable time in biological reactors. We are currently exploring the use of both membrane reactors as well as microbial electrolytic cells for this purpose.