Ancient and recent gold mine activities led to soil and groundwater pollution with various metal and metalloids including arsenic in North-West Iran. Drinking and irrigation water wells have been sampled with arsenic levels between 110 and 200 μg/L. The aquifer chosen for testing ColFerroX particles was located close to a small village. The water table was ca. 6.5 meters below ground and the Darcy flow was ca. 0.2 m/day.