The present disclosure provides for a method of filtering pollutants from a contaminated fluid stream. The method includes disposing unprepared humic shale in a container, contacting the unprepared humic shale with an aqueous solution, maintaining the aqueous composition in contact with the unprepared humic shale for a period of time, drying the humic shale, and then placing polluted water in contact with the humic shale until pollutants have been removed from the fluid.