Kate M. Campbell

TL;DR: Recent advances in the understanding of biogeochemical redox processes are highlighted and their impact on contaminant fate and transport, including future research needs are highlighted.

TL;DR: Using molecular genetics, it is shown that the functional gene for As(V) respiration, arrA, is highly conserved; that it is required for As (V) reduction to arsenite when arsenic is sorbed onto iron minerals; and that it can be used to identify the presence and activity of As( V)-respiring bacteria in arsenic-contaminated iron-rich sediments.

TL;DR: In this article, the authors present results from an in situ study of uranium redox transitions occurring in aquifer sediments under sulfate-reducing conditions, and they propose a biotic-abiotic transition pathway in which biomass-hosted mackinawite (FeS) is an electron source to reduce U(VI) to U(IV), which subsequently reacts with biomass to produce monomeric u(IV) species.

TL;DR: In this paper, high-iron sediments in North Haiwee Reservoir (Olancha, CA), resulting from water treatment for removal of elevated dissolved arsenic in the Los Angeles Aqueduct system, were studied to examine arsenic partitioning between solid phases and porewaters undergoing shallow burial.

TL;DR: Of the two pathways for microbial As(V) reduction (respiration and detoxification), the respiratory pathway was dominant under these experimental conditions, and As( III) adsorbed onto the surface of HFO enhanced the rate of microbial Fe(III) reduction.