A pair of state groups has launched a registry for chemicals used in extracting natural gas through hydraulic fracturing.
The online registry makes it easier for the public to find out what chemicals are being used to extract natural gas in nearby wells, but participating drillers will continue to withhold information about chemicals they consider proprietary.
Drillers have used a process known as "fracking" to unlock vast reserves of natural gas trapped in formations underneath several states. The process involves the high-pressure injection of water, sand and chemicals to break up rock and release the natural gas.
Policymakers, regulators and environmental protection groups have pressured drillers to disclose the chemicals they use. Twenty-four drillers have agreed to list some of them on the site.
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