Development of an on-Line Hyperpure Germanium Process Radiation Monitoring System

The use of hyperpure germanium detectors for process radiation monitoring in large nuclear power plants has been investigated. A portable hyperpure germanium detector assembly and electronics were used to acquire on-line spectra of Letdown System fluid activities during both power operations and plant shutdown. Meaningful data was obtained despite background radiation levels to 70 mr/hr and pipe contact radiation levels to 80 mr/ hr. Comparison of the test data to the site laboratory analysis proves this system can operate accurately in a power plant environment.