{"accessLevel": "public", "bureauCode": ["010:12"], "contactPoint": {"@type": "vcard:Contact", "fn": "Peter B McMahon", "hasEmail": "mailto:pmcmahon@usgs.gov"}, "description": "Water samples from 50 domestic wells located <1 kilometer (km) (proximal) and >1 km (distal) from shale-gas wells in upland areas of the Marcellus Shale region were analyzed for chemical, isotopic and groundwater-age tracers. Uplands were targeted because natural mixing with brine and hydrocarbons from deep formations is less common in those areas compared to valleys. Methane (CH4) -isotope and pre-drill CH4 data indicate one proximal sample (5 percent of proximal samples) contains thermogenic CH4 (2.6 milligrams per liter (mg/L)) associated with shale-gas production. Chloride (Cl), bromide (Br), lithium (Li), and neon-20 (20Ne)/argon-36 (36Ar) data suggest that CH4 leaked from a nearby gas well in a gas phase. Another proximal sample contains volatile hydrocarbons (0.03-0.4 micrograms per liter (\u00b5g/L)), including benzene, found in some hydraulic fracturing fluid. Modeled groundwater-age distributions, calibrated to tritium (3H), sulfur hexafluoride (SF6), and carbon-14 (14C) concentrations, indicate that water recharged prior to shale-gas development, suggesting surface releases associated with shale-gas production were not the source of those hydrocarbons, although leakage from a nearby gas well directly into the old groundwater cannot be ruled out. Estimated age distributions in the samples span ~20 to >10,000 years and have implications for relating occurrences of hydrocarbons in groundwater to surface releases associated with recent shale-gas production, and to the time required to flush contaminants from the system.  This data release contains isotopic tracer, noble gas, and groundwater-age tracer concentration data collected by the U.S. Geological Survey and data for pH, specific conductance, major ions, and methane collected by Chesapeake Energy Corporation.", "distribution": [{"@type": "dcat:Distribution", "description": "The metadata original format", "downloadURL": "https://data.usgs.gov/datacatalog/metadata/USGS.5c58ad28e4b0708288ff2ab6.xml", "format": "XML", "mediaType": "text/xml", "title": "Original Metadata"}, {"@type": "dcat:Distribution", "accessURL": "https://doi.org/10.5066/P93M7JCD", "description": "Landing page for access to the data", "format": "XML", "mediaType": "application/http", "title": "Digital Data"}], "identifier": "http://datainventory.doi.gov/id/dataset/USGS_5c58ad28e4b0708288ff2ab6", "keyword": ["Cycle 3", "USGS:5c58ad28e4b0708288ff2ab6", "Pennsylvania", "Wyoming County, PA", "Shale-gas well", "Hydrocarbons", "Bradford County, PA", "Groundwater-age distribution", "Water quality", "Broome County, NY", "NAWQA", "New York", "Groundwater", "Marcellus Shale", "Susquehanna County, PA", "Sullivan County, PA", "Tioga County, NY", "Domestic well"], "modified": "2020-08-26T00:00:00Z", "publisher": {"@type": "org:Organization", "name": "U.S. Geological Survey"}, "spatial": "-77.0989898925, 41.142764154, -75.2590423178, 42.5552347924", "theme": ["geospatial"], "title": "Data Release for Hydrocarbons in Upland Groundwater, Marcellus Shale Region, Northeastern Pennsylvania and Southern New York, USA"}