The main function of radiochemical surveillance in a nuclear power plant is to monitor the transport of radioactive materials in and out of various systems, including the fuel integrity evaluation and the control of radioactive material release to the environment. Radiochemical analyses of iodine activities in the reactor coolant to assess fuel integrity during normal operation and to characterize the nature of fuel failure are demonstrated. Assessment of fission products released by the so-called recoil process is emphasized in the study. Measurements of 91Sr and 92Sr in reactor water are recommended as the recoil indicators and to determine the fuel particle contamination on fuel surfaces. In an operating BWR/6 with a recoil level at ~1.2 × 1013 fission/s operated at ~2980 MW(thermal), ~30 g of fuel particle contamination was estimated.