Tex. Water Code § 27.020

The commission is authorized to develop a regulatory program with respect to the injection of fluid associated with the mining of sulfur by the Frasch process in accordance with the provisions of this chapter. The commission may not impose any requirements more stringent than those promulgated by the administrator of the United States Environmental Protection Agency pursuant to the federal Safe Drinking Water Act, 42 U.S.C. 300h et seq., as amended, unless the commission determines that more stringent regulations are necessary to protect human health or the environment.