This research report describes an effort to develop a prototype petroleum oil-in-water monitoring system that will continuously measure oil (whether free, suspended, dissolved, or emulsified) in water carrying a variety of potential interfering substances. An extensive desk-top survey of commercially available oil monitors was carried out. Three devices were selected for thorough laboratory evaluation: (1) Sigrist Fluorescence Monitor Model FLJ, (2) CE Invalco D.O.W. Monitor, and (3) Horiba OCMA-25 Oil Content Monitor. The laboratory evaluation of the three oil detectors forms the majority of this report. The work is described in detail, including the construction of a flow loop and its operation, the installation of the selected detectors in the breadboard system, the development of a data retrieval system, the calibration methodology employed, the initial checkout of the detectors, and the extensive multidetector evaluation of each detector's performance for quantifying petroleum oil in the presence of impurities and other interferents. Included is a comprehensive discussion of results and conclusions derived from the data reduction phase of the work. The interferent effect and the sensitivity, linearity and accuracy, repeatability, response speed, and reliability of each detector are described in detail. Recommendations for a preliminary design for the prototype system and a suggested program plan to develop it are also given.

Caption title. "Sep. 1981." "EPA-600/2-81-206." Microfiche.