The ZEA (zero valent iron, ethylenediaminetetraacetic acid (EDTA), and air) organic pollutant degradation system has been previously shown to degrade a variety of organic pollutants and chemical warfare agent surrogates; however, mechanistic details and reactive intermediates formed in this system have not been identified. It is hypothesized that the ZEA system produces reactive oxygen species (H2O2, HO center dot) by the reduction of oxygen by Fe(II)EDTA(aq). This hypothesis is examined through an electrochemical model of the ZEA system. A carbon basket electrode is used as the reducing agent in place of Fe(0). The Fe(III)EDTA complex (0.5 mM) is electrochemically reduced to Fe(II)EDTA at an applied potential of -120 mV (vs Ag/AgCl) under aerobic conditions. Hydrogen peroxide was observed to form in the presence of the metal complex with a maximum concentration reaching 0.139 mM H2O2 after 3 h of electrolysis. In the absence of FeEDTA, 0.04 mM H2O2 is obtained by the direct reduction of O-2 at the electrode surface. Electron resonance spectroscopy (ESR), along with 5,5-dimethyl-1-pyrroline-N-oxide (DMPO) as a spin trap and methanol as a radical scavenger confirms the formation of HO center dot produced via the Fenton reaction in the electrochemical system. Hydroxyl radical attack on EDTA caused the degradation of Fe(II/III)EDTA to a steady-state concentration of 0.14 mM from 0.5 mM as observed by HPLC. The pH of the electrolysis solution increased from 2.64 to 9.25 during 6 h of reductive electrolysis which is indicative of the consumption of H+ during the reduction of O-2 to form H2O2. These experiments provide evidence that the ZEA system uses atmospheric O-2 to produce reactive oxygen species including those that deeply oxidize organics under room temperature and pressure conditions.