Methane (CH4) emissions from municipal solid waste (MSW) landfills pose a significant environmental risk due to CH4's high global warming potential and flammability. Modern landfills utilize gas collection systems to reduce these emissions; however, their effectiveness is often compromised by a limited radius of influence. The efficacy of conventional soil cover (SC), designed to limit landfill gas (LFG) release, varies based on factors such as CH4 concentration, oxygen availability, and soil properties. This study investigates the spatial variability of potential CH4 oxidation in SC systems to determine if CH4 oxidation occurs uniformly across the surface. To achieve this, a near-field scale rectangular tank (measuring 50 cm × 50 cm × 100 cm) was fabricated, and an SC system was established within it. This system includes a clayey soil layer (also known as a biocover layer), intended to decrease precipitation infiltration and facilitate microbial CH4 oxidation, which is overlaid by a sand drainage layer and topsoil. Various compositions and flow rates of synthetic LFG were introduced into the system. After the experiment, the system was dismantled to collect samples from various depths and locations to analyze spatial variations in moisture content (MC), organic content (OC), pH, and electrical conductivity (EC). Batch tests on selected samples from the biocover layer were conducted to measure potential CH4 oxidation rates. Results show significant variability in CH4 oxidation rates within the biocover layer, ranging from 71.9 to 260.2 µg CH4/g-day, with the highest activity observed at 70 cm below ground surface (bgs). Notable spatial variations in oxidation rates were observed, ranging from 95.3 to 148.4 µg CH4/g-day at 50 cm and from 34.7 to 102.4 µg CH4/g-day at 85 cm, in contrast to 70 cm bgs. Overall, the CH4 oxidation rates within the SC system were found to vary both in terms of depth and spatial distribution at the same depth.