The study used the RIAM technique to evaluate environmental sustainability using an environmental impact assessment through nine sessions of focus group discussions in the affected mining communities. The system's methodology involves assigning scores to impact component issues based on predetermined criteria, which are then transferred into arrangements that indicate the extent of positive or negative effects. The RIAM analysis reveals that kimberlite diamond mining has predominant negative environmental impacts across all three communities, A, B, and C. However, certain social and economic components reflected positive changes. Nevertheless, the positive impacts on those three communities are just about the same. From the total scores summary for the three communities, it is obvious that the kimberlite mining in the affected communities have negative effects than the positive effects. Based on these findings, recommendations were made for improvement.