Fig. 6 Concentrations of aqueous As(T), As(V), and As(III) versus time as Pt electrode E_H decreased in a stirred goethite suspension with a low As:Fe molar ratio (5.3 x 10^-4). Suspension was inoculated with a CN-0 population on Day 2 and N₂(g) replaced O₂(g) on Day 3 to promote reduction