Selected ground-water-quality data of the Lockport Dolomite in Darke, Miami, Montgomery, and Preble Counties, Ohio

In 1998, 25 samples of ground water from the Lockport Dolomite in western Ohio were analyzed for major ions, trace elements, and arsenic. Samples were collected from residential wells in Darke, Miami, Montgomery, and Preble Counties. The water sampled was untreated, except perhaps for water from one well. In general, samples from the northern part of the study area had the highest concentrations of common constituents such as calcium, magnesium, potassium, sulfate, boron, and strontium. Iron and strontium concentrations were generally high throughout the study area, with median concentrations of 4,500 ?g/L (micrograms per liter) and 1,500 ?g/L, respectively. Arsenic concentrations, which ranged from less than 1 ?g/L to 29 ?g/L, did not exceed the drink ing-water standard of 50 ?g/L.