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This study aimed to investigate the influence of historical peat mining on current sedimentation and sediment quality in Håtjärnen, Håsjön and primarily Yttersjön. One sediment sample were collected from Håtjärnen and from Håsjön, along with 23 additional samples from Yttersjön. Sampling sites in Yttersjön were strategically located from upstream to downstream, near an inlet draining the nearest peat mining site, to assess its impact on sediment composition. This study analyzed subaqueous sediments, which consists of three constituents: minerogenic material, organic material (OM), and biogenic silica (Si). The sediment geochemistry was analyzed through loss on ignition, X-ray fluorescence, Near Infrared spectroscopy, Si/Al-ratio and lastly C/N ratio serving as a proxy for the origin of OM. No patterns in variation were observed in OM, Si/Al ratio, chlorophyll content, or C/N ratios between the upstream and downstream samples in Yttersjön, suggesting that the peat drainage inlet has a negligible impact on the sediment composition. In comparison, Håtjärnen and Håsjön displayed similar compositions of the sediment. An earlier study conducted in this area reported high sediment accumulation rates for the lakes investigated, as well as a substantial organic composition that included peat residues. These new findings, which contradict the earlier study, highlights the importance of analyzing all constituents of sediment to obtain a comprehensive understanding of the sediment composition.