Hydrochemistry of the White Rock Canyon Springs and Rio Grande, New Mexico
Wednesday, February 26, 2014: 10:00 a.m.
Ballroom 2 (Crowne Plaza Albuquerque)
Patrick Longmire, PhD
,
New Mexico Environment Department, Department of Energy Oversight Bureau, Los Alamos, NM
Michael R. Dale
,
New Mexico Environment Department, Hazardous Waste Bureau, Los Alamos, NM
Kim P. Granzow
,
New Mexico Environment Department, DOE Oversight Bureau, Los Alamos, NM
David Englert
,
New Mexico Environment Department, Department of Energy Oversight Bureau, Santa Fe, NM
Stephen M. Yanicak
,
New Mexico Environment Department, DOE Oversight Bureau, Los Alamos, NM
Thirty-six springs located in White Rock Canyon (WRC) represent significant discharge zones for the deep vadose zone and upper portions of the regional aquifer beneath the Pajarito Plateau, New Mexico. Based on results of stable isotope analyses (δ18O and δ2H), recharge to the WRC springs occurs within the Sierra de los Valles and along canyon bottoms within several watersheds dissecting the Pajarito Plateau. The majority of springs in WRC discharge immediately west of the Rio Grande, with three springs discharging near the east bank of the river. The springs vary in flow ranging from less than one to 900 L/min, discharging from sedimentary (Chamita Formation), volcanic (Cerros del Rio basalt) and volcanoclastic (Puye Formation) aquifers. An estimated total discharge for the WRC springs west of the Rio Grande is 2940 m3/day. Unadjusted carbon-14 ages for the WRC springs range from 2100 to 9700 years before present and decrease in age from north to south, representing groundwater-flow paths of variable length. Results of tritium/helium dating suggest that groundwater-flow paths leading to the WRC springs are controlled by complex lithological and hydraulic properties of the vadose zone and regional aquifer. Groundwater sampled from the WRC springs is characterized by sodium-calcium-bicarbonate, calcium-sodium-bicarbonate, and mix cation-anion compositions with concentrations of TDS ranging from 171 to 476 mg/L. The three WRC springs discharging east of the Rio Grande contain higher concentrations of natural solutes, including bicarbonate, sodium, calcium, and uranium, which represent discharge zones for deep groundwater flow originating from the Sangre de Cristo Mountains. Several of the WRC springs contain elevated above background concentrations of tracers, including chloride, nitrate, perchlorate, tritium, and uranium derived from industrial and municipal sewage outfalls and deicing salt. Monitoring of the WRC springs provides data essential for evaluating long-term sustainability and contaminant vulnerability of the regional aquifer.
Handout
Patrick Longmire, PhD, New Mexico Environment Department, Department of Energy Oversight Bureau, Los Alamos, NM
Patrick Longmire is an aqueous geochemist with 38 years of experience in chemical characterization of aquifer systems. His expertise includes field and experimental investigations on the fate and transport of inorganic chemicals, reactive transport modeling, and stable isotope geochemistry. Longmire has taught short courses on groundwater geochemistry for the National Ground Water Association since 1987.
Michael R. Dale, New Mexico Environment Department, Hazardous Waste Bureau, Los Alamos, NM
Michael Dale is a hydrogeologist with the New Mexico Environment Department. He conducts hydrogeochemical investigations, including measuring naturally-occurring perchlorate and delineating groundwater flow paths using isotopic and chemical tracers. Dale has 16 years of experience in the fields of hydrochemistry and hydrogeology.
Kim P. Granzow, New Mexico Environment Department, DOE Oversight Bureau, Los Alamos, NM
Kim Granzow is an environmental scientist/geologist with the New Mexico Environment Department. She specializes in environmental monitoring for naturally occurring and anthropogenic contaminants such as perchlorate and plutonium, and uses Geographic Information Systems (GIS) in hydro-contaminant investigations. Granzow has 15 years of experience in the field of geology and eight years of experience in GIS.
David Englert, New Mexico Environment Department, Department of Energy Oversight Bureau, Santa Fe, NM
David Englert is a geologist with the DOE Oversight Bureau, New Mexico Environment Department, and has more than 30 years of experience in oil and gas exploration and environmental investigations.
Stephen M. Yanicak, New Mexico Environment Department, DOE Oversight Bureau, Los Alamos, NM
Stephen Yanicak is a Natural Science Manager and geologist with the New Mexico Environment Department at Los Alamos. He manages a team of scientists that have been supporting State and DOE/UC groundwater investigations at Los Alamos National Laboratory for the past 13 years. Hydrologists staffed at the State Environment Department office in Los Alamos specialize in evaluating and delineating radionuclides and other isotopic and chemical tracers on the Pajarito Plateau within the vicinity of Los Alamos National Laboratory. Yanicak has an M.S. from New Mexico State and a B.S. from Sonoma State.
