Sewage plume in a sand and gravel aquifer, Cape Cod, Massachusetts

at Otis Air Force Base 5 Hydrogeology 5 Hydrology 7 Results of chemical analyses 9 Introduction 9 Maps and sections used to present results 9 Selected constituents and properties 11 Specific conductance and temperature 11 Boron 13 Chloride and sodium 13 Phosphorus 14 Nitrogen 18 Ammonia, nitrate, and dissolved oxygen 18 Detergents 20 Discussion 22 Processes that affect the distribution of contaminants in the plume 22 Vertical location of the plume 24 Path of the plume 25 Summary 25 Selected references 27 FIGURES 1 .Map showing study area 2 2. Map showing physical and cultural features 4 3 .Photograph showing Otis Air Force Base sewage treatment plant 6 4. Graph showing volume of sewage treated at the Otis Air Force Base treatment plant from 1936 through 1980 7 5 .Geologic section showing hydrogeologic units in the study area 7 6.Map showing water-table contours and direction of ground-water flow 8 7. Idealized diagram showing relationship between the center of the plume and the map and sections used to describe the distributions of contaminants 11 8. Map showing areal distribution of specific conductance and temperature of ground water 12 9. Longitudinal and transverse sections showing vertical distribution of boron in ground water 14 10 .Map showing areal distribution of chloride and sodium in ground water 15 11 .Longitudinal sections showing vertical distribution of chloride and sodium in ground water 16 12 .Map showing areal distribution of phosphorus in ground water 17 13 .Map showing areal distribution of nitrogen in ground water 19