[en] This report contains environmental monitoring data collected at the Feed Materials Production Center during 1977. These data show that the average boundary concentrations of airborne radioactive contaminants from FMPC operations were no greater than 0.4% of the guide levels published in ERDA Manual Chapter 0524. The resulting offsite radiation exposures would, therefore, be a small fraction of the standards for uncontrolled areas. Radionuclides in wastewater did not present a significant potential for radiation exposure. Concentrations of environmentally important nonradioactive contaminants in water and air are also reported. Results show that FMPC operations did not cause State standards for these contaminants to be exceeded