Mobile treatment systems and methods for use in removing sulfates from contaminated water using a pre-treatment subsystem configured to remove particulates and debris from the contaminated water and to produce pre-treated water; a treatment subsystem configured to remove sulfates from the pre-treated water and to produce treated water, the treatment subsystem including at least one treatment tank with a collection unit having one or more filters with pore or inlet sizes of approximately 0.35-1.2 mm; and at least one storage tank configured to collect the treated water. Optionally, the systems and methods may use a backwash subsystem configured to backwash the treatment subsystem.