We report the e-beam radiolysis of polychlorinated biphenyls (PCBs) in a continuous flow system, and the development of remote, real-time detection using gas chromatography. Aroclor-containing transformer oil was recirculated through an irradiation cell irradiated with 13-MeV electrons, at a flow rate of approximately 0.1 L/min. The analytical equipment was protected from the beam by a 1.1-m concrete barrier. Data are presented showing the decrease in PCB concentration versus absorbed dose for pure transformer oil solution, and oil spiked with alkaline isopropanol to increase the PCB decomposition rate. Efficiency of PCB removal is expressed in terms of the dose constant, with units of reciprocal dose.