WASHINGTON - A long-delayed report released today by the U.S. Environmental Protection Agency finds that fracking has polluted drinking water. But a lack of cooperation from the oil and gas industry limited the study’s ability to draw wider conclusions. “The limited amount of data collected before and during hydraulic fracturing activities reduces the ability to determine whether hydraulic fracturing affected drinking water resources in cases of alleged contamination,” the study notes.

“The EPA found disturbing evidence of fracking polluting our water despite not looking very hard,” said Kassie Siegel of the Center for Biological Diversity. “This study was hobbled by the oil and gas industry’s refusal to provide key data. After years of analysis, New York wisely concluded that fracking is just too dangerous to allow. Fracking causes unacceptable damage to our water, air, and wildlife, and the Obama administration needs to ban it.”

The EPA delayed publishing this draft study for almost five years, even as other researchers have tied fracking and other oil and gas industry activities to water-pollution problems.

In May a study in the Proceedings of the National Academy of Sciences found fracking chemicals in drinking water at homes in Pennsylvania. In California the oil industry has dumped billions of gallons of waste fluid into protected aquifers with water clean enough to drink. The state of New York recently banned fracking after extensive scientific analysis of the technique’s threats to water, air and public health.

The EPA previously found that fracking likely polluted water in Wyoming, Pennsylvania and Texas, but the agency halted those investigations after coming under pressure from the oil and gas industry.

Fracking blasts huge volumes of water mixed with toxic chemicals into the earth at high pressures to break up rock formations and release oil and gas. About 25 percent of fracking chemicals could cause cancer, scientists say. Others harm the skin or reproductive system.