References Cited


Andrews, J.N., 1992, Mechanisms for noble gas dissolution by groundwaters, in International Atomic Energy Agency, ed., Isotopes of Noble Gases as Tracers in Environmental Studies: Vienna, International Atomic Energy Agency, p. 87–110.


Busenberg, Eurybiades, and Plummer, L.N., 1992, Use of chlorofluorocarbons (CCl₃F and CCl₂F₂) as hydrologic tracers and age-dating tools—The alluvium and terrace system of central Oklahoma: Water Resources Research, v. 28, p. 2,257–2,283.


Busenberg, Eurybiades, and Plummer, L.N., 2000, Dating young groundwater with sulfur hexafluoride—Natural and anthropogenic sources of sulfur hexafluoride: Water Resources Research, v. 36, p. 3,011–3,030.


Dunkle, S.A., Plummer, L.N., Busenberg, Eurybiades, Phillips, P.J., Denver, J.M., Hamilton, P.A., Michel, R.L., and Coplen, T.B., 1993, Chlorofluorocarbons (CCl₃F and CCl₂F₂) as dating tools and hydrologic tracers in shallow groundwater of the Delmarva Peninsula, Atlantic Coastal Plain, United States: Water Resources Research, v. 29, p. 3,837–3,860.


Ekwurzel, Brenda, Schlosser, Peter, Smethie, W.M., Jr., Plummer, L.N, Busenberg, Eurybiades, Michel, R.L., Weppernig, Ralf, and Stute, Martin, 1994, Dating of shallow groundwater—Comparison of the transient tracers ³H/³He, chlorofluorocarbons, and ⁸⁵Kr: Water Resources Research, v. 30, p. 1,693–1,708.


Gilliom, R.J., Alley, W.M., and Gurtz, M.E., 1995, Design of the National Water-Quality Assessment Program—Occurrence and distribution of water-quality conditions: U.S. Geological Survey Circular 1112, 33 p.


Hinkle, S.R., Shapiro, S.D., Plummer, L.N., Busenberg, Eurybiades, Widman, P.K., Casile, G.C., and Wayland, J.E., 2010, Estimates of tracer-based piston-flow ages of groundwater from selected sites—National Water-Quality Assessment Program, 1992–2005: U.S. Geological Survey Scientific Investigations Report 2010–5229, 90 p. (Also available at http://pubs.usgs.gov/sir/2010/5229/.)


International Atomic Energy Agency, 2006, Use of chlorofluorocarbons in hydrology—A Guidebook: Vienna, International Atomic Energy Agency, 277 p.


National Oceanic and Atmospheric Administration, 2008, NOAA calibration scales for various trace gases: National Oceanic and Atmospheric Administration, accessed December 12, 2011, at http://www.esrl.noaa.gov/gmd/ccl/scales.html.


Plummer, L.N., and Busenberg, Eurybiades, 2000, Chlorofluorocarbons, in Cook, P.G., and Herczeg, A.L., eds., Environmental Tracers in Subsurface Hydrology: Boston, Kluwer, p. 441–478.


Plummer, L.N., and Mullin, A.H., 1997, Collection, processing, and analysis of ground-water samples for tritium/helium-3 dating: U.S. Geological Survey National Water Quality Laboratory Technical Memorandum 97.04S, accessed December 7, 2011, at http://nwql.usgs.gov/Public/tech_memos/nwql.1997-04S.pdf.


Schlosser, Peter, Stute, Martin, Sonntag, Christian, and Münnich, K.O., 1989, Tritiogenic ³He in shallow groundwater: Earth and Planetary Science Letters, v. 94, p. 245–256.


Solomon, D.K., and Cook, P.G., 2000, ³H and ³He, in Cook, P.G., and Herczeg, A.L., eds., Environmental Tracers in Subsurface Hydrology: Boston, Kluwer, p. 397–424.


Stute, Martin, and Schlosser, Peter, 2000, Atmospheric noble gases, in Cook, P.G., and Herczeg, A.L., eds., Environmental Tracers in Subsurface Hydrology: Boston, Kluwer, p. 349–377.


Thatcher, L.L., 1962, The distribution of tritium fallout in precipitation over North America: Bulletin of the International Association of Scientific Hydrology, v. 7, p. 48–58.


U.S. Geological Survey, 2010, Complete listing of NAWQA’s study units and summary reports: website, accessed December 12, 2011, at http://water.usgs.gov/nawqa/studies/study_units_listing.html. 


U.S. Geological Survey, 2011, USGS National Water Quality Assessment Data Warehouse: website, accessed December 12, 2011, at http://infotrek.er.usgs.gov/apex/f?p=NAWQA:HOME:0.


Walker, S.J., Weiss, R.F., and Salameh, P.K., 2009, Reconstructed histories of the annual mean atmospheric mole fractions for the halocarbons CFC-11, CFC-12, CFC-113 and carbon tetrachloride: University of California San Diego, accessed December 12, 2011, at http://bluemoon.ucsd.edu/pub/cfchist/.

First posted July 31, 2012