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Z.F.; Fram; M.S.; Faulkner; K.E.; Alpers; C.N.; Soltero; E.M.; and Taylor; K.A., 2020, Effects of montane watershed development on vulnerability of domestic groundwater supply during drought, Hydrology, v. 583, article 124567, http://doi.org/10.1016/j.jhydrol.2020.124567 Jurgens; B.C.; Fram; M.S.; Rutledge; J.; and Bennett; G.L., 2020, Identifying areas of degrading and improving groundwater-quality conditions in the State of California USA 1974–2014, Environmental Monitoring and Assessment, v. 192, article 250, http://doi.org/10.1007/s10661-020-8180-y Bennett; G.L., 2020, Updated Study Reporting Levels (SRLs) for Trace-Element Data Collected for the California Groundwater Ambient Monitoring and Assessment (GAMA) Program Priority Basin Project October 2009–October 2018, U.S. Geological Survey Scientific Investigations Report 2020-5034, 24 p., http://doi.org/10.3133/sir20205034 Kent; R.; Johnson; T.D.; and Rosen; M.R., 2020, Status and trends of orthophosphate concentrations in groundwater used for public supply in California, Environmental Monitoring and Assessment, v. 192, article 550, http://doi.org/10.1007/s10661-020-08504-x Burow; K.R.; Floyd; W.D.; and Landon; M.K., 2019, Factors affecting 1 2 3-trichloropropane contamination in groundwater in California, Science of The Total Environment, v. 672, p. 324-334, http://doi.org/10.1016/j.scitotenv.2019.03.420 Voss; S.A.; Jurgens; B.C.; Fram; M.S.; and Bennett; G.L.V., 2019, Delineation of spatial extent depth thickness and potential volume of aquifers used for domestic and public water-supply in the Central Valley California, U.S. Geological Survey Scientific Investigations Report 2019-5076, 34 p., http://doi.org/10.3133/sir20195076 Fram; M.S.; and Stork; S.V., 2019, Determination of study reporting limits for pesticide constituent data for the California Groundwater Ambient Monitoring and Assessment Program Priority Basin Project 20042018Part 1: National Water Quality Schedules 2003 2032 or 2033 and 2060, U.S. Geological Survey Scientific Investigations Report 2019-5107, 129 p., http://doi.org/10.3133/sir20195107 Rosen; M.R.; Burow; K.R.; and Fram; M.S., 2019, Anthropogenic and geologic causes of anomalously high uranium concentrations in groundwater used for drinking water supply in the southeastern San Joaquin Valley CA, Journal of Hydrology, v. 577, article 124009, http://doi.org/10.1016/j.jhydrol.2019.124009 Hansen; J.A.; Jurgens; B.; and Fram; M.S., 2018, Quantifying anthropogenic contributions to century-scale groundwater salinity changes San Joaquin Valley California USA, Science of the Total Environment, v. 642, p. 125-136, http://doi.org/10.1016/j.scitotenv.2018.05.333 Burton; C.A.; and Wright; M.T., 2018, Status and understanding of groundwater quality in the Monterey-Salinas Shallow Aquifer Study Unit 2012-13: California GAMA Priority Basin Project, U.S. Geological Survey Scientific Investigations Report 2018-5057, 132 p., http://doi.org/10.3133/sir20185057 Kent; R., 2018, Variations on a method for evaluating decadal-scale changes in the groundwater quality of two GAMA coastal study units 2004-14 California GAMA Priority Basin Project, U.S. Geological Survey Scientific Investigations Report 2018-5088, 90 p., http://doi.org/10.3133/sir20185088 Fram; M.S., 2017, Groundwater quality in the Western San Joaquin Valley study unit 2010: California GAMA Priority Basin Project, U.S. Geological Survey Scientific Investigations Report 2017-5032, 130 p., http://doi.org/10.3133/sir20175032 Mathany; T.M.; and Burton; C.A., 2017, Status and understanding of groundwater quality in the Bear Valley and Lake Arrowhead Watershed Study Unit 2010: California GAMA Priority Basin Project, U.S. Geological Survey Scientific Investigations Report 2017-5043, 71 p., http://doi.org/10.3133/sir20175043 Fram; M.S.; Jasper; M.; and Taylor; K.A., 2017, Groundwater quality in the Yuba River and Bear River watersheds Sierra Nevada California, U.S. Geological Survey Open-File Report 2017-1115, 4 p., http://doi.org/10.3133/ofr20171115 Bennett; G.L.V., 2017, Status and understanding of groundwater quality in the North San Francisco Bay Shallow Aquifer study unit 2012; California GAMA Priority Basin Project, U.S. Geological Survey Scientific Investigations Report 2017-5051, 74 p., http://doi.org/10.3133/sir20175051 Jurgens; B.C.; Bohlke; J.K.; Kauffman; L.J.; Belitz; K.; and Esser; B.K., 2016, A partial exponential lumped parameter model to evaluate groundwater age distributions and nitrate trends in long-screened wells, Journal of Hydrology, v. 543, no. A, p. 109-126, http://doi.org/10.1016/j.jhydrol.2016.05.011 Visser; A.; Moran; J.E.; Hillegonds; D.J.; Singleton; M.J.; Kulongoski; J.T.; Belitz; K.; and Esser; B.K., 2016, Geostatistical analysis of tritium groundwater age and other noble gas derived parameters in California, Water Research, v. 91, p. 314-330, http://doi.org/10.1016/j.watres.2016.01.004 Davis; T.A.; and Kulongoski; J.T., 2016, Status of groundwater quality in the Santa Barbara Study Unit 2011: California GAMA Priority Basin Project, U.S. Geological Survey Scientific Investigations Report 2016-5112, 82 p., http://doi.org/10.3133/sir20165112 Kent; R.; and Landon; M.K., 2016, Triennial changes in groundwater quality in aquifers used for public supply in California: utility as indicators of temporal trends, Environmental Monitoring and Assessment, v. 188, article 610, http://doi.org/10.1007/s10661-016-5618-3 Belitz; K.; Fram; M.S.; and Johnson; T.D., 2015, Metrics for assessing the quality of groundwater used for public Supply CA USA: equivalent-population and area, Environmental Science and Technology, v. 49, no. 14, p. 8330-8338, http://doi.org/10.1021/acs.est.5b00265 Izbicki; J.A.; Wright; M.T.; Seymour; W.A.; McCleskey; R.B.; Fram; M.S.; Belitz; K.; and Esser; B.K., 2015, Cr(VI) occurrence and geochemistry in water from public-supply wells in California, Applied Geochemistry, v. 63, p. 203-217, http://doi.org/10.1016/j.apgeochem.2015.08.007 Deeds; D.A.; Kulongoski; J.T.; Muhle; J.; and Weiss; R.F., 2015, Tectonic activity as a significant source of crustal tetrafluoromethane emissions to the atmosphere: observations in groundwaters along the San Andreas Fault, Earth and Planetary Science Letters, v. 412, p. 163-172, http://doi.org/10.1016/j.epsl.2014.12.016 Mathany; T.M.; and Belitz; K., 2015, Status and understanding of groundwater quality in the Northern Coast Ranges Study Unit 2009: California GAMA Priority Basin Project, U.S. Geological Survey Scientific Investigations Report 2014-5215, 86 p., http://doi.org/10.3133/sir20145215 Fram; M.S.; and Shelton; J.L., 2015, Status and understanding of groundwater quality in the Cascade Range and Modoc Plateau Study Unit 2010: California GAMA Priority Basin Project, U.S. Geological Survey Scientific Investigations Report 2014-5238, 131 p., http://doi.org/10.3133/sir20145238 Wright; M.T.; Fram; M.S.; and Belitz; K., 2015, Geochemical conditions and the occurrence of selected trace elements in groundwater basins used for public drinking-water supply Desert and Basin and Range Hydrogeologic Provinces 2006-11, U.S. Geological Survey Scientific Investigations Report 2014-5173, 48 p., http://doi.org/10.3133/sir20145173 Johnson; T.D.; and Belitz; K., 2015, Identifying the location and population served by domestic wells in California, Journal of Hydrology: Regional Studies, v. 3, p. 31-86, http://doi.org/10.1016/j.ejrh.2014.09.002 Wright; M.T.; Stollenwerk; K.G.; and Belitz; K., 2014, Assessing the solubility controls on vanadium in groundwater northeastern San Joaquin Valley CA, Applied Geochemistry, v. 48, no. 0, p. 42-53, http://doi.org/10.1016/j.apgeochem.2014.06.025 Bennett; G.L.; V; Fram; M.S.; and Belitz; K., 2014, Status and Understanding of Groundwater Quality in the Klamath Mountains Study Unit 2010: California GAMA Priority Basin Project, U.S. Geological Survey Scientific Investigations Report 2014-5065, 58 p., http://doi.org/10.3133/sir20145065 Parsons; M.C.; Hancock; T.C.; Kulongoski; J.T.; and Belitz; K., 2014, Status of groundwater quality in the Borrego Valley Central Desert and low-use basins of the Mojave and Sonoran Deserts study unit 2008-2010: California GAMA Priority Basin Project, U.S. Geological Survey Scientific Investigations Report 2014-5001, 88 p., http://doi.org/10.3133/sir20145001 Parsons; M.C.; Kulongoski; J.T.; and Belitz; K., 2014, Status and understanding of groundwater quality in the South Coast Interior groundwater Basins 2008: California GAMA Priority Basin Project, U.S. Geological Survey Scientific Investigations Report 2014-5023, 68 p., http://doi.org/10.3133/sir20145023 Davis; T.A.; Olsen; L.D.; Fram; M.S.; and Belitz; K., 2014, Updated study reporting levels (SRLs) for trace-element data collected for the California Groundwater Ambient Monitoring and Assessment (GAMA) Priority Basin Project October 2009-March 2013, U.S. Geological Survey Scientific Investigations Report 2014-5105, 52 p., http://doi.org/10.3133/sir20145105 Forrest; M.J.; Kulongoski; J.T.; Edwards; M.S.; Farrar; C.D.; Belitz; K.; and Norris; R.D., 2013, Hydrothermal contamination of public supply wells in Napa and Sonoma Valleys California, Applied Geochemistry, v. 33, p. 25-41, http://doi.org/10.1016/j.apgeochem.2013.01.012 Burton; C.A.; Land; M.T.; and Belitz; K., 2013, Status and understanding of groundwater quality in the South Coast Range-Coastal Study Unit 2008: California GAMA Priority Basin Project, U.S. Geological Survey Scientific Investigations Report 2013-5053, 86 p., http://doi.org/10.3133/sir20135053 Kent; R.H.; and Landon; M.K., 2013, Trends in concentrations of nitrate and total dissolved solids in public supply wells of the Bunker Hill Lytle Rialto and Colton groundwater Subbasins San Bernardino County California: Influence of legacy land use, Science of The Total Environment, v. 452-453, p. 125-136, http://doi.org/10.1016/j.scitotenv.2013.02.042 Landon; M.K.; Burton; C.A.; Davis; T.A.; Belitz; K.; and Johnson; T.D., 2013, Statistical evaluation of variables affecting occurrence of hydrocarbons in aquifers used for public supply California, Journal of the American Water Resources Association, p. 1-17, http://doi.org/10.1111/jawr.12129 Parsons; M.C.; Kulongoski; J.T.; and Belitz; K., 2013, Status and understanding of groundwater quality in the San Francisco Bay groundwater basins 2007: California GAMA Priority Basin Project, U.S. Geological Survey Scientific Investigations Report 2012-5248, 76 p., http://doi.org/10.3133/sir20125248 Kulongoski; J.T.; Hilton; D.R.; Barry; P.H.; Bradley; K.E.; Hillegonds; D.J.; and Belitz; K., 2012, Volatile fluxes through the Big Bend section of the San Andreas Fault California: Helium and carbon-dioxide systematics, Chemical Geology, v. 339, p. 92-103, http://doi.org/10.1016/j.chemgeo.2012.09.007 Fram; M.S.; and Belitz; K., 2012, Status and understanding of groundwater quality in the Tahoe-Martis Central Sierra and Southern Sierra Study Units 2006-2007: California GAMA Priority Basin Project, U.S. Geological Survey Scientific Investigations Report 2011-5216, 222 p., http://doi.org/10.3133/sir20115216 Burton; C.A.; Shelton; J.L.; and Belitz; K., 2012, Status and understanding of groundwater quality in the two southern San Joaquin Valley study units 2005-2006: California GAMA Priority Basin Project, U.S. Geological Survey Scientific Investigations Report 2011-5218, 150 p., http://doi.org/10.3133/sir20115218 Landon; M.K.; and Belitz; K., 2012, Geogenic sources of benzene in aquifers used for public supply California, Environmental Science & Technology, v. 46, no. 16, p. 8689-8697, http://doi.org/10.1021/es302024c Deeds; D.A.; Kulongoski; J.T.; and Belitz; K., 2012, Assessing California groundwater susceptibility using trace concentrations of halogenated volatile organic compounds, Environmental Science and Technology, v. 46, no. 24, p. 13128-13135, http://doi.org/10.1021/es303546b Land; M.T.; Kulongoski; J.T.; and Belitz; K., 2012, Status of groundwater quality in the San Fernando-San Gabriel Study Unit 2005: California GAMA Priority Basin Project, U.S. Geological Survey Scientific Investigations Report 2011-5206, 66 p., http://doi.org/10.3133/sir20115206 Dawson; B.J.M.; and Belitz; K., 2012, Status of groundwater quality in the California Desert Region 2006-2008: California GAMA Priority Basin Project, U.S. Geological Survey Scientific Investigations Report 2012-5040, 110 p., http://doi.org/10.3133/sir20125040 Goldrath; D.A.; Fram; M.S.; Land; M.T.; and Belitz; K., 2012, Status of groundwater quality in the coastal Los Angeles Basin 2006: California GAMA Priority Basin Project, U.S. Geological Survey Scientific Investigations Report 2012-5048, 64 p., http://doi.org/10.3133/sir20125048 Kent; R.H.; and Belitz; K., 2012, Status of groundwater quality in the Upper Santa Ana Watershed November 2006-March 2007: California GAMA Priority Basin Project, U.S. Geological Survey Scientific Investigations Report 2012-5052, 88 p., http://doi.org/10.3133/sir20125052 Shelton; J.L.; Fram; M.S.; Belitz; K.; and Jurgens; B.C., 2012, Status and understanding of groundwater quality in the Madera-Chowchilla Study Unit 2008 - California GAMA Priority Basin Project, U.S. Geological Survey Scientific Investigations Report 2012-5094, 86 p., http://doi.org/10.3133/sir20125094 Fram; M.S.; Olsen; L.D.; and Belitz; K., 2012, Evaluation of volatile organic compound (VOC) blank data and application of study reporting levels to groundwater data collected for the California GAMA Priority Basin Project May 2004 through September 2010, U.S. Geological Survey Scientific Investigations Report 2012-5139, 94 p., http://doi.org/10.3133/sir20125139 Landon; M.K.; Green; C.T.; Belitz; K.; Singleton; M.J.; and Esser; B.K., 2011, Relations of hydrogeologic factors groundwater reduction-oxidation conditions and temporal and spatial distributions of nitrate Central-Eastside San Joaquin Valley California USA, Hydrogeology Journal, v. 19, no. 6, p. 1203-1224, http://doi.org/10.1007/s10040-011-0750-1 Burton; C.A.; Montrella; J.; Landon; M.K.; and Belitz; K., 2011, Status and understanding of groundwater quality in the Santa Clara River Valley 2007: California GAMA Priority Basin Project, U.S. Geological Survey Scientific Investigations Report 2011-5052, 67 p., http://doi.org/10.3133/sir20115052 Kulongoski; J.T.; Belitz; K.; Landon; M.K.; and Farrar; C.D., 2011, Status and understanding of groundwater quality in the Monterey Bay and Salinas Valley Groundwater Basins 2005: California GAMA Priority Basin Project, U.S. Geological Survey Scientific Investigations Report 2011-5058, 60 p., http://doi.org/10.3133/sir20115058 Wright; M.T.; and Belitz; K., 2011, Status and understanding of groundwater quality in the San Diego Drainages Hydrogeologic Province 2004: California GAMA Priority Basin Project, U.S. Geological Survey Scientific Investigations Report 2011-5154, 71 p., http://doi.org/10.3133/sir20115154 Fram; M.S.; and Belitz; K., 2011, Occurrence and concentrations of pharmaceutical compounds in groundwater used for public drinking-water supply in California, Science of The Total Environment, v. 409, no. 18, p. 3409-3417, http://doi.org/10.1016/j.scitotenv.2011.05.053 Fram; M.S.; and Belitz; K., 2011, Probability of detecting perchlorate under natural conditions in deep groundwater in California and the Southwestern United States, Environmental Science & Technology, v. 45, no. 4, p. 1271-1277, http://doi.org/10.1021/es103103p Landon; M.K.; Green; C.T.; Belitz; K.; Singleton; M.J.; and Esser; B.K., 2011, Distribution of reduction-oxidation conditions and changes in nitrate concentrations over time in groundwater Central-Eastside San Joaquin Valley California, Hydrogeology Journal, v. 19, p. 1203-1224, http://doi.org/10.1007/s10040-011-0750-1 Landon; M.K.; Belitz; K.; Jurgens; B.C.; Kulongoski; J.T.; and Johnson; T.D., 2010, Status and understanding of groundwater quality in the Central-Eastside San Joaquin Basin 2006, U.S. Geological Survey Scientific Investigations Report 2009-5266, 97 p., http://doi.org/10.3133/sir20095266 Kulongoski; J.T.; Belitz; K.; Landon; M.K.; and Farrar; C.D., 2010, Status and understanding of groundwater quality in the North San Francisco Bay groundwater basins 2004: California GAMA Priority Basin Project, U.S. Geological Survey Scientific Investigations Report 2010-5089, 65 p., http://doi.org/10.3133/sir20105089 Bennett; G.L.; V; Fram; M.S.; Belitz; K.; and Jurgens; B.C., 2010, Status and understanding of groundwater quality in the northern San Joaquin Basin 2005: California GAMA Priority Basin Project, U.S. Geological Survey Scientific Investigations Report 2010-5175, 67 p., http://doi.org/10.3133/sir20105175 Jurgens; B.C.; Fram; M.S.; Belitz; K.; Burow; K.R.; and Landon; M.K., 2010, Effects of groundwater development on uranium: Central Valley California USA, Ground Water, v. 48, no. 6, p. 913-928, http://doi.org/10.1111/j.1745-6584.2009.00635.x Olsen; L.D.; Fram; M.S.; and Belitz; K., 2010, Review of trace-element field-blank data collected for the California Groundwater Ambient Monitoring and Assessment (GAMA) Program May 2004-January 2008, U.S. Geological Survey Scientific Investigations Report 2009-5220, 47 p., http://doi.org/10.3133/sir20095220 Bennett; G.L.; V; Fram; M.S.; Belitz; K.; and Jurgens; B.C., 2010, Status of groundwater quality in the Southern Middle and Northern Sacramento Valley Study Units 2005-08: California GAMA Priority Basin Project, U.S. Geological Survey Scientific Investigations Report 2011-5002, 119 p., http://doi.org/10.3133/sir20115002 Belitz; K.; Jurgens; B.; Landon; M.K.; Fram; M.S.; and Johnson; T., 2010, Estimation of aquifer scale proportion using equal area grids: Assessment of regional scale groundwater quality, Water Resources Research, v. 46, no. W11550, http://doi.org/10.1029/2010WR009321 Wright; M.T.; and Belitz; K., 2010, Factors controlling the regional distribution of vanadium in California groundwater, Groundwater, v. 48, no. 4, p. 515-525, http://doi.org/10.1111/j.1745-6584.2009.00666.x Johnson; T.D.; and Belitz; K., 2009, Assigning land use to supply wells for the statistical characterization of regional groundwater quality: Correlating urban land use and VOC occurrence, Journal of Hydrology, v. 370, no. 1-4, p. 100-108, http://doi.org/10.1016/j.jhydrol.2009.02.056 Densmore-Judy; J.N.; Belitz; K.; Wright; M.T.; Dawson; B.J.M.; Johnson; T.D.; and Hudson; G.B., 2005, Evaluation of volatile organic compounds in two Mojave Desert basins--Mojave River and Antelope Valley--in San Bernardino Los Angeles and Kern Counties June-October 2002, U.S. Geological Survey Scientific Investigations Report 2004-5248, 51 p., http://doi.org/10.3133/sir20045248 Wright; M.T.; Belitz; Kenneth; and Johnson; Tyler, 2004, Assessing the susceptibility to contamination of two aquifer systems used for public water supply in the Modesto and Fresno metropolitan areas California 2001 and 2002, U.S. Geological Survey Scientific Investigations Report 2004–5149, 35 p., http://doi.org/10.3133/sir20045149 Belitz; K.; Dubrovsky; N.M.; Burow; K.R.; Jurgens; B.C.; and Johnson; T.D., 2003, Framework for a ground-water quality monitoring and assessment program for California, U.S. Geological Survey Water Resources Investigations Report 03-4166, 78 p., http://doi.org/10.3133/wri034166