Calcium-based stabilizers are frequently used by The Oklahoma Department of Transportation (ODOT) to enhance the strength and reduce the swelling potential of fine-grained soils. However, these stabilizers can lead to adverse reactions in high sulfate-bearing soils which are very common in Oklahoma. This study aimed to explore the efficacy of Ground Granulated Blast Furnace Slag (GGBFS) as an additive for high sulfate-bearing soils, by comparing the performance of GGBFS with other stabilizers like lime and Portland cement. In this research, the primary evaluation tests were the unconfined compression test (UCT), to evaluate the strength gained from the addition of the stabilizer, and the response to wetting test to study swelling behavior. Two test soils were manufactured that contained approximately 20,000 ppm of sulfate in the form of ground gypsum. In addition to the gypsum, Test Soil 1 was made with equal amounts of fine sand and kaolinite and Test Soil 2 with equal amounts of fine sand and montmorillonite. The results indicate that adding between 6% and 12% GGBFS by dry weight of soil significantly increased the unconfined compressive strength (UCS), and the optimum amount of GGBFS was 8% by dry weight of soil for both test soils. With the addition of the 8% GGBFS, the UCS of Test Soil 1 and Test Soil 2 increased on average by 40 psi and 50 psi, respectively. These values are close to the 50 psi increase desired for chemical stabilizers according to ODOT requirements in OHD L-50. Additionally, when GGBFS was combined with a small amount of either lime (0.5% or 1%) or PC (1% or 3%), a significant increase in the UCS was observed compared to untreated samples or the ones only treated with one additive. The introduction of 1% lime and 7% GGBFS increased the UCS around 200 psi for Test Soil 1 and 94 psi for Test Soil 2. The combination of 3% PC and 7% exhibited the highest UCS increase, reaching 300 psi for Test Soil 1 and 140 psi for Test Soil 2. ix The incorporation of GGBFS was observed to decrease the swelling behavior in both test soils during a response-to-wetting test lasting approximately 15 days. The addition of 8% GGBFS decreased the vertical swell from 3.3% to 1.9% for Test Soil 1 and from 5.2% to 0.3% for Test Soil 2. Most notably, both soils exhibited no apparent swelling after the first day of the test, which is in contrast to all other tests containing lime, PC or GGBFS mixed with lime or PC. When lime or PC was used alone or in combination with GGBFS, swelling continued throughout the testing period. In some cases for Test Soil 1, the final amount of swelling exceeded that of the test soil alone, which is a clear indication of adverse reactions occurring due to addition of lime or PC. That the GGBFS completely halted the swelling behavior while all the mixes containing lime or PC continued to swell at the end of the nearly 15-day tests is an important finding. It suggests that adverse reactions may not be avoidable even with small amounts of PC or lime mixed with GGBFS. The addition of GGBFS to the test soils had a minimal impact on the Liquid Limit, Plastic Limit, and Plasticity Index of the test soils. However, for both test soils the Shrinkage Limit was significantly reduced with the addition of 8% GGBFS. For Test Soil 1 and Test Soil 2, respectively, the SL reduced from about 9.5% and 18% for the untreated soil to about 1.5% and 6% for the treated soil.