This is a combined dataset from the USGS Orphaned Well Dataset (Grove and Merrill, 2022) and publicly available data from the USGS National Water Information System (NWIS) obtained via the Water Quality Portal using the USGS Python dataretrieval library. This dataset is composed of water quality measurements from groundwater sites located within 1 mile of the locations of unplugged orphaned wells listed in the United States Documented Unplugged Orphaned Oil and Gas Well Dataset. This dataset contains measurements of common water quality parameters (pH, temperature, specific conductance, TDS), dissolved light hydrocarbons and their isotopes (Methane, δ13C in methane, δ2H in methane, ethane, δ13C in ethane, propane, and butane), constituents that can indicate the presence of brines and geologic fluids and be used to assess corrosivity (calcium, chloride, bromide, alkalinity), measurements that can be used to assess the potential for biogenic methane production (sulfate, sulfur isotopes, oxidation/reduction potential), as well as isotopic tracers of hydrologic processes (δ2H and δ18O in water and tritium). The data include supporting information about the water quality measurement sites that can help provide context to the water quality measurements. The data is presented in several ways, including all individual measurements, the average water quality near each orphaned well in the dataset, water quality measurements averaged near orphaned well (less than 100 meters), and averaged for distances at further away (100 meters to 1.6 kilometers), as well as the combined subset of data where there are measurements for both the near (less than 100 meters) and far (between 100 meters an 1.6 kilometer) radius. This data release also includes the script and input file used to retrieve and format the data from NWIS to allow use in other projects.