Some water utility representatives have protested Environmental Working Group’s report of...worrisome levels of chromium-6, a suspected carcinogen, in the drinking water of 31 cities across the country. Yet the tap water industry...conduct[ed] its own extensive survey in 2004 that found clear evidence of widespread chromium-6 pollution in untreated source water. The survey, conducted by...an offshoot of the American Water Works Association, obtained data...from 189 utilities in 41 states. The conclusion: chromium-6 is common in American groundwater...There is no indication that customers of the 189 participating utilities were advised of the chemical’s presence in source waters in their communities...Erin Brockovich...who helped residents of tiny Hinkley, Calif, win a $333 million settlement from Pacific Gas & Electric Co, accused of dumping the chemical in local ground water...[said] “I’d like to say I’m surprised at the utilities’ silence, but I’m not”...