Semi-generic saturated and unsaturated flow models, incorporating advection and dispersion, were developed to examine the effects of soil (Hapludoll, Calciaquoll and Haplaquoll) hydrology on the long-term sources and processes affecting the sulfate distribution in a shallow confined glaciofluvial aquifer (0 to 12 m), and in the underlying silt (appr. 12 to 28 m) and till (appr. 28 to 100 m). It was determined that the original source of high sulfate was the oxidation of pyrite in the glacial deposit, and that the modern concentration distribution was caused by the redistribution of sulfate in the natural flow system since the oxidizing event. A modeling technique was developed that enabled the identification of both the approximate initial sulfate concentration and the redistribution time following the oxidizing event. The models indicated that the oxidizing event had occurred approximately 3,000 to 8,000 y B.P. This conforms approximately to the time of the Hypsithermal Interval. Water and matrix chemistry, 34S isotope distribution, and 34S diffusion analysis support the model conclusions. Results indicate that soil hydrology can indirectly affect water chemistry as deep as 30 m below land surface.