The herbicide atrazine was incorporated in the granules manufactured in the process of tumbling agglomeration to obtain controlled release (CR) formulations. The formulations contained bentonite as a CRmatrix forming agent (960–974 g/kg of dry granules), atrazine (10 g/kg), citric acid (3.2 g/kg), and sodium alginate as a matrix binder and a release modifier (12.8–26.8 g/kg). The release characteristics of atrazine were studied by immersion of the granules in static water. The effects of formulations on atrazine transport through soil were studied using model soil columns irrigated with water. The release of atrazine from CR granules into water was affected by increasing the alginate concentration in a particular formulation because the time necessary for the release of 50% of the active ingredient was longer for the granules containing a higher amount of alginate. The CR formulations significantly reduced the amount of atrazine leached to the soil surface horizon in comparison with the commercial water suspension of the herbicide.