This research investigates the effect of bacterial chemotaxis on degradation rate in an experimental model for in situ bioremediation (ISB). The process of sensing an attractant chemical by a motile bacterium and subsequent motion towards that attractant, known as chemotaxis, occurs in Pseudomonas putida G7, Pseudomonas stutzeri KC, Rhizobium meliloti, and many other subsurface strains along with Escherichia coli. To date, there have been no widely accepted experimental studies that demonstrate whether bacterial chemotaxis can enhance biodegradation of contaminants, which can be chemoattractants, in the subsurface. This research presents novel experimental methodologies, developed to investigate bacterial chemotaxis and migration, providing for the systematic evaluation of the effect of the chemotaxis phenomenon in a saturated porous medium. The hypothesis formulated is that bacteria undergoing chemotaxis in a porous medium will be able to sense an attractant chemical, bias their motion towards it, and subsequently degrade the attractant at a higher rate than bacteria exhibiting non-chemotactic behavior by increasing the bacterial density in the contaminated region. This experimental model has been developed to measure the degradation rate of serine, a simulated contaminant and chemoattractant. E. coli RP437 was used as a representative chemotactic in situ bacteria while E. coli RP5700, a tsr- mutant strain of RP437 that lacks the serine chemoreceptor, was used as the non-chemotactic control strain. RP5700 exhibits random motility similar to RP437 in the presence and absence of serine gradients. These two strains were highly characterized for this work, a process which was rigorous and performed in more detail than in prior works. Chemotactic ability of RP437 toward 1 mM serine was validated via capillary and swarm plate assays. Swimming speeds, run lengths, and turn angles were compared using a tracking microscope and were statistically similar. Serine uptake rates in liquid media were also statistically similar: 861.94 ± 39 pmol/(min·10⁷ CFU) for RP437 and 882.84 ± 44 pmol/(min·10⁷ CFU) for RP5700. These results show that these strains are suitable for investigating any enhancing effect of chemotaxis on biodegradation rate. For ISB experiments, a model aquifer has been designed to introduce RP437 and RP5700 bacteria to serine in saturated sand via a sharp gradient. The aquifer was used to compare serine degradation rates and migration rates through sand. Degradation rate results over a 21 hour period were 4.5 x 10^-3 ± 1.3 x 10^-3 mM/h for RP437 and 4.6 x 10^-3 ± 1.4 x 10^-3 mM/h for RP5700. These results show that the degradation rate of serine was statistically similar for both strains, indicating that enhancement was not detected. The experimental parameters chosen for this study did not elucidate degradation or migration enhancements due to chemotaxis. However, the experimental methodologies developed to acquire these results represent novel contributions to the field of chemotaxis analysis in porous media. These methodologies can easily be extended for the variation of other sets of parameters, such as particle size, cell densities, growth conditions, and selection of chemoattractants. An additional test in the enhancement of chemotaxis to complement these results was performed. Chemical enhancement of chemotaxis was tested in a simple swarm plate study with growth where caffeine was used to stimulate RP437 bacteria. With the addition of 1.0 µg/ml and 10 µg/ml caffeine, swarms were 8.5% larger in diameter relative to a control with no caffeine. This represents 16% more biomass growing and penetrating into the agar. While degradation in the swarm plates was not measured, this result demonstrates the potential for enhancement of migration and degradation in ISB systems. A significant result of this work was the success of using the RP437/RP5700 pair for chemotaxis studies, due to their high degree of similarity. This similarity is likely due to the fact that RP437 is the parent strain for RP5700. It is recommended that work with this pair continue in studies comparing chemotactic and non-chemotactic behavior.