01646nam 2200421 450 991070443250332120150708093836.0(CKB)5470000002441372(OCoLC)913472189(EXLCZ)99547000000244137220150708d2012 ua 0engurcn|||||||||txtrdacontentcrdamediacrrdacarrierUse of classes based on redox and groundwater age to characterize the susceptibility of principal aquifers to changes in nitrate concentrations, 1991 to 2010 /by P.B. McMahonReston, Virginia :U.S. Department of the Interior, U.S. Geological Survey,2012.1 online resource (51 unnumbered pages) color illustrations, color mapsScientific investigations report ;2012-5220Title from title screen (viewed on July 2, 2015).Includes bibliographical references (pages 33-35).GroundwaterAnalysisAquifersUnited StatesAnalysisGroundwaterPollutionNitratesGroundwaterAnalysis.AquifersAnalysis.GroundwaterPollution.Nitrates.McMahon Peter B.1387740Geological Survey (U.S.),GPOGPOBOOK9910704432503321Use of classes based on redox and groundwater age to characterize the susceptibility of principal aquifers to changes in nitrate concentrations, 1991 to 20103528232UNINA