WASHINGTON (AP) -- The Environmental Protection Agency has released a progress report on its research into potential impacts of natural gas hydraulic fracturing and drilling on drinking water.
The update released Friday doesn't come to any conclusions and the final report won't be released until 2014.
The EPA says information on fracking chemicals has been collected from nine companies and 24,925 wells. Computer analysis is also being done on well construction.
The EPA says it is working with scientists, the industry, and environmental groups to examine any possible impacts. Sampling at five locations in Colorado, North Dakota, Pennsylvania, and Texas has been completed, and lab studies are being done on drilling wastewater.
The industry and many states say the process is safe when done properly, but critics dispute that.