Some Montanans are suing to protect their water by requiring transparency from the oil and gas industry, specifically related to fracking.

On Tuesday, a handful of landowners from eastern Montana and two nonprofit organizations sued the Montana Board of Oil and Gas Conservation after it refused to consider their July petition to require oil and gas companies to disclose the chemicals used in their fracking fluids. The petition also asked that if a company claimed it didn’t have to disclose the chemicals because they were trade secrets, the company should be required to prove that the mixture qualified as a trade secret.