This metadata record consists of 3 tables containing per-and-poly-fluoroalkyl substances (PFAS) and polychlorinated biphenyls (PCB) concentration data of wastewater and biosolid samples from wastewater treatment plants within the Patapsco and Potomac watersheds. The PCB concentration data was used to assess the occurrence and fate of PCB in wastewater treatment plants within the Patapsco watershed, from December 2021 to December 2022; The PFAS concentration data was used to assess the occurrence and fate of PFAS within the Patapsco and Potomac watersheds, from 2021-2023. The PFAS total oxidizable precursors (TOP) assay data were used to investigate PFAS fate in the wastewater treatment process of plants within the Patapsco watershed from March and September of 2022.