'Missing lead' in Flint water pipes confirms cause of crisis - A study of lead service lines in Flint's damaged drinking water system reveals a Swiss cheese pattern in the pipes' interior crust, with holes where the lead used to be.

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'Missing lead' in Flint water pipes confirms cause of crisis - A study of lead service lines in Flint's damaged drinking water system reveals a Swiss cheese pattern in the pipes' interior crust, with holes where the lead used to be.