By Timothy Gardner WASHINGTON, May 11 (Reuters) - The U.S. Environmental Protection Agency said drinking water is safe to consume in a small Pennsylvania town that has attracted national attention after residents complained about hydraulic fracturing, or fracking, for natural gas. The EPA has tested water at 61 homes in Dimock, Pennsylvania, where residents have complained since 2009 of cloudy, foul-smelling water after Cabot Oil & Gas Corp drilled for gas nearby. "This set of sampling did not show levels of contaminants that would give EPA reason to take further action," Roy Seneca, a spokesman for the regional EPA office, said about the final set of data released Friday. The agency released data for only 59 of the homes as they could not contact residents at two of them. Dimock became ground zero for the debate about fracking after Josh Fox, the director of Oscar-nominated 2010 documentary called "Gasland," visited the town and met residents who feared their water was contaminated by the drilling. Techniques including fracking have revolutionized the U.S. natural gas industry by giving companies access to vast new reserves that could supply the country's demand for 100 years, according to the industry. Environmental and health groups, however, say that some fracking operations near homes and schools pollute land and water. The agency found one well in the last batch of data that contained methane, a main component of natural gas. Seneca would not say what the agency thought the source of that methane was, but said the agency will conduct a review of the data. Residents have complained that methane could be from fracking, but industry groups say methane can occur naturally in wells in energy-rich areas. Claire Sandberg, the executive director for Water Defense, an anti-fracking group, said methane, which was also found in the previous EPA results, was dangerous to people with heart and lung problems. The EPA will re-sample four wells where previous Cabot and state data showed levels of contaminants, but where EPA's first round of testing did not find levels that would require action, Seneca said. Over the course of the EPA tests that have been released since mid-March, contaminants were found in some wells. But the EPA said those levels were safe. In the first set of tests, for example, six of 11 homes showed concentrations of sodium, methane, chromium or bacteria. Arsenic was also found at two homes, but, again, levels were deemed safe. "Safe levels have not been established for numerous chemicals that were found in the test samples, although many can cause serious health ailments," said Sandberg. Cabot spokesman George Stark said any contaminants found in the tests "are more likely indicative of naturally occurring background levels or other unrelated activities." Another three Dimock homeowners had wanted their water to be sampled by the EPA but they have not scheduled a time for the testing.