Heavy metal contamination and health risk assessment of groundwater ingestion in proximal relation to waste dumpsites in Port Harcourt were investigated during the rainy and dry season of 2020. Five (5) sampling points were established and designated as Groundwater (GW) as follows: GW1, GW2, GW3, GW4, and GW5 respectively. The control station used was GW5. Nine (9) heavy metals (Cd, As, Mn, Cu, Hg, Ni, Fe, Pb, and Zn) were assessed during the period using an atomic absorption spectrometer and were compared with National Standard for Drinking Water Quality (NSDWQ) of Nigeria. The Estimated Daily Intakes of Metal (EDIM) of these metals for adult males, females, and children revealed no significant health issues during the wet and dry seasons. However, the Health Risk Index (HRI) for non-carcinogenic revealed that during the wet season Pb in the control station (GW5) had a concentration of 4.000E+0 mg/kg/day that was far higher than unity (HRI<1) for females. The Arsenic (As) values for children at GW1, 2, and 3 were also higher than unity. The pollution index for each heavy metal across sample location showed that Fe in GW1 and 3 during the dry season was high while in the wet season, values for Cu in GW4 was very high, Fe in GW1 and 2, and Mn in GW2 were higher than the unity. The overall pollution index of the heavy metal studied revealed that only Fe exceeded the unity value during the dry season whereas Cu, Fe, Pb, and Mn concentrations were also higher during the wet season. This calls for concern considering the vulnerability of children and women who may have been exposed to groundwater sources via ingestion. The heavy metal contamination as observed in this study may have occurred due to anthropogenic activities superimposed by the unregulated insanitary waste disposal phenomenon.