http://fivethirtyeight.com/features/what-went-wrong-in-flint-water-crisis-michigan/
What Went Wrong In Flint
Officials at the Michigan Department of Environmental Quality, the agency in charge of making sure water is safe in the state, made a series of decisions that had disastrous consequences:
Against federal guidelines, they chose not to require the Flint water plant to use optimized corrosion control, despite telling the Environmental Protection Agency they were doing so in an email on Feb. 27, 2015.
They took few samples and took them from the wrong places, using a protocol known to miss important sources of lead, which some say didn’t comply with a 25-year-old law meant to prevent lead exposure in residential water.
They threw out two samples whose inclusion would have put more than 10 percent of the tests above what’s known as the “actionable level” of lead, 15 parts per billion. Had the DEQ not done so, the city would have been required to warn residents that there was a problem with lead in the water back in the summer of 2015, or possibly earlier.
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