KEWAUNEE COUNTY, Wis.—Chuck Wagner has given up on drawing clean water from his faucets.
When he moved, 23 years ago, to 80 acres situated between dairy farms in northeastern Wisconsin, he built a home and drilled a 123-foot well. The water tested clean, and his family drank it. Five years later, tests showed it was contaminated with bacteria and nitrates, potentially harmful and often derived from nitrogen in manure and fertilizer.
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