A method of treating a wastewater is provided and can be used, for example, to treat a gas well hydrofracture wastewater. The method can involve precipitating barium as barium sulfate, precipitating calcium and strontium as calcium carbonate and strontium carbonate, precipitating magnesium hydroxide, and filtering out the metal compounds to form a recycle water. The recycle water produced from the method is also provided, as is a method for using the recycle water as a gas well hydrofracture water. In some embodiments, discharge water from a coal mine, and/or water from an abandoned coal mine, is used as a source of sulfate ions to precipitate barium as barium sulfate.