In this study, we investigated the grain size, total organic carbon (TOC), and heavy metal (Fe, Li, Cu, Zn, Pb, Cd, Cr, As, Ni, Hg) distribution in surface sediments collected near abalone aquaculture farms in the Wando region. The sediments were primarily composed of silt and clay, with sand and gravel observed in certain areas. TOC content was strongly correlated with mean grain size, with an average of 0.76%. This suggests that it may be related to organic matter from aquaculture operations. Heavy metals such as Ni, Cd, Zn, and Cu were influenced by aquaculture activities and organic matter accumulation, Cd showed the highest enrichment levels, identifying it as a substantial pollutant. Cd accumulation was linked to residual seaweed deposition and exchange processes associated with CaCO3 precipitation. Ecological risk assessment showed that most areas posed a moderate risk, with Cd identified as the primary factor contributing to ecological hazards.