Natural contaminants, arsenic and uranium, in one-fifth of California’s groundwater

Natural contaminants are more prevalent than human-made contaminants in California groundwater used for public supply, is the conclusion of a decade-long study by U.S. Geological Survey scientists. The study evaluated the quality of nearly all of the groundwater used for public supply in California and is the most comprehensive assessment of groundwater in any state to date. Groundwater provides about one-third of California’s drinking supply in a typical year, but more during drought conditions. —> Read More