Estimated short-term yields of and quality of ground water in stratified-drift aquifer areas in the Neponset River Basin, Massachusetts

This report presents the estimated short-term yields and quality of ground water in stratifieddrift aquifer areas in the Neponset River Basin, Massachusetts. Stratified glacial drift forms the major aquifer areas in the basin. These thin valley-fill aquifer areas of sand and gravel have saturated thicknesses of as much as 130 feet and widths that reach a maximum of 8,000 feet in some of the bedrock valleys. For 14 selected aquifer areas, estimated shortterm yields from aquifer storage, which is repre- sentative of short-term duration yield available during severe drought conditions, ranged from 2.1 to 12.4 cubic feet per second after 30 days of pumping and from 0.3 to 7.1 cubic feet per second after 180 days of pumping. Ground water in the basin tends to be slightly acidic, of low to moderate hardness, and hasrelatively low concentrations of dissolved solids. Sodium is the dominant cation and chloride the dominant anion. In one-half of the wells sampled, iron and manganese concentrations exceeded the U.S. Environmental Protection Agency Secondary Maximum Contaminant Levels (SMCL's) of 300 and 50 micrograms per liter, respectively.