An　integrated　simulation-assessment　modeling　approach　for　analyzing　environmental　risks　of　groundwater　contamination　is　proposed　in　this　paper.　It　incorporates　an　analytical　groundwater　solute　transport　model,　an　exposure　dose　model,　and　a　fuzzy　risk　assessment　model　within　a　general　framework.　The　transport　model　is　used　for　predicting　contaminant　concentrations　in　subsurface,　and　the　exposure　dose　model　is　used　for　calculating　contaminant　ingestion　during　the　exposure　period　under　given　exposure　pathways.　Both　models　are　solved　through　the　Monte　Carlo　simulation　technique　to　reflect　the　associated　uncertainties.　Based　on　consideration　of　fuzzy　relationships　between　exposure　doses　and　cancer　risks,　risk　levels　of　different　exposure　doses　for　each　contaminant　can　be　calculated　to　form　a　fuzzy　relation　matrix.　The　overall　risks　can　then　be　quantified　through　further　fuzzy　synthesizing　operations.　Thus,　probabilistic　quantification　of　different　risk　levels　(possibilities)　can　be　realized.　Results　of　the　case　study　indicate　that　environmental　risks　at　the　waste　landfill　site　can　be　effectively　analyzed　through　the　developed　methodology.　They　are　useful　for　supporting　the　related　risk-management　and　remediation　decisions.