Potential environmental hazards associated with heavy metals have been reported at Al-diwaniyah open dump in Iraq. Therefore, the levels of heavy metals and their spatial and temporal variability have been studied, in addition to pollution indices (HPI, HEI, Cd) to achieve environmental management and sustainability. Concentrations of seven heavy metals in groundwater wells at various distances around dumpsite were analyzed for the period 2022-2023 using atomic absorption spectrophotometer. Results revealed that heavy metals levels in samples examined decreased with the distance from the dumpsite W1>W2>W3 and it followed this pattern: Cd <Ni <Cr <Pb<Cu < Fe < Zn, with average concentrations in dry and rainy seasons were Zn (0.641,0.305), Fe (0.199,0.375), Cu (0.208,0.068), Pb (0.035,0.117), Cr (0.031,0.073), Ni (0.106,0.055), Cd (0.023,0.0095). On one hand, seasonal variation showed that 57.14% of heavy metals were raising in the dry season, and on the other, pollution indices showed that the groundwater taken from the W1 site was heavily polluted and unfit for consumption, while the other two sites were in low pollution category, which showed little impact of waste dumps on groundwater in these sites. Analysis results indicated that groundwater is appropriate for drinking purposes compared to the permissible limits of WHO/IQS, apart from those taken from site W1. All wells also provide water suitable for irrigation purposes based on the guidelines of the Food and Agriculture Organization (FAO). The Statistical analysis demonstrated a strong correlation between some heavy metals, in addition to the influence of sampling sites on heavy metal levels. It is recommended to expand this study to include additional regions in order to provide more environmental monitoring for groundwater and examine its potential human health risks in the study region, construct an engineering landfill equipped with leachate collector system, moreover, systematic treatment of heavy metals concentrations should be carried out regularly.