Arsenic Removal from Groundwater in the Black Canyon City Area

Project goal: To design a process for removing arsenic from groundwater in the Black Canyon City area to meet maximum EPA contaminant limit standards. Arsenic occurs naturally in groundwater but is especially prevalent in areas near mining operations. Long-term arsenic exposure has been linked to severe medical conditions,including cancer. This project creates potable water by removing arsenic from groundwater via four major processes: chlorination, adsorption, desorption and precipitation. Chlorination oxidizes arsenic, disinfects water, and lowers pH for optimal arsenic removal. Adsorption uses granulated ferric hydroxide to remove arsenic from the water, leaving an arsenic content that is below the maximum containment level and safe for human consumption. Desorption is performed when the adsorbent is saturated with arsenic so that the granulated ferric hydroxide can be regenerated and reused. Desorption produces a concentrated arsenic brine that can be further treated to precipitate out the arsenic as a solid to be disposed of as hazardous waste.