The threat of leachate as pollutant on groundwater and soil is of growing concern to human and the environment. The threat is caused by movement of contaminants through leachate from dumpsites and its location to water bodies both at the surface and underground. This research is focused on the impact of leachate from a dumpsite of a residential institution on the groundwater and soil in order to determine the degree of contamination around the institution’s environment. The physico- and bio-chemical analysis: BOD, COD, pH, DO, TDS, total hardness, nitrite, chloride, calcium and heavy metals such as Pb, Fe, Zn, and Cu, in line with international standards, were carried out on both soil and water samples obtained from different points on the dumpsite. The results obtained from the tests carried out were compared to the World Health Organization (WHO) and Nigerian Standard for Drinking Water Quality (NSDWQ) standards. Heavy metal concentration showed significant variations from one sample point to another. On comparison, most of the parameters checked in the water samples from boreholes and the streams close to the dumpsites were within the allowable limits except for the Salinity, Iron (Fe) and Calcium (Ca) that exceeded the standards. There is a significant level of acidity which would require proper treatment in order to avoid harm to consumers in the future. The soil samples were also tested after digestion and the results showed that Nitrite (NO2-) and BOD5 exceeded the allowable limits. These results show that the dumpsite has slight effects on the adjacent stream and underlying soil. Therefore, the implementation of a properly designed leachate collection system to prevent future risk of continuous contamination of the underlying soil and groundwater is important.