Sample and Specific Conductance Monitoring Site Approximately 2.5 kilometers downstream from the USGS stream gage 13046995 (Latitude N 44°03'43", Longitude W 111°09'07", NAD83). Methods
Specific Conductance Data An In-Situ Aqua Troll 100 Data Logger was used to measure and store specific conductance measurements. Specific conductance measurements were made every 15 minutes. The specific conductance monitoring data were periodically checked against discrete measurements. The hand-held field meter used for discrete measurements and the continuous specific conductance probe were calibrated using NIST traceable standards and measurements were made following the procedure described in the USGS National Field Manual (USGS, 2015). Water Quality Data Samples were collected near the specific conductance monitoring sites. At the time of collection, all waters samples were filtered through a syringe filter (0.45-micrometer). Two splits of the filtered water were retained for chemical analyses, including an unacidified (FU) sample for determination of anion concentrations and a nitric acid preserved (FA; 1% volume-to-volume concentrated trace-metal grade nitric acid) sample for cation and trace metal analyses. During sample collection, the water temperature, specific conductance, and pH were measured. Concentrations of chloride, fluoride, bromide, and sulfate were determined with an ion chromatograph (Dionex DX600). Analytical errors for these constituents were typically less than 2%. Total alkalinity as bicarbonate was determined by titration with sulfuric acid to the bicarbonate end-point. The analytical error in alkalinity concentrations was approximately ± 3%. Concentrations of cations and trace metals were determined with an inductively coupled plasma-optical emission spectroscopy (Perkin Elmer Optima 7300 DV) following the methods described in Ball and others (2010). Arsenic concentrations for selected samples was determined by hydride generation atomic absorption spectroscopy (Perkin Elmer PinAAcle 900T). Quality Control (QC) analyses included standard reference water samples, sample replicates, and blanks. The accuracy of the water chemistry data was checked by calculating charge and specific conductance balance using PHREEQCI (McCleskey, 2018; McCleskey and others, 2012). Results Specific Conductance Data The file FallSC.csv contains the date and time of each measurement and the specific conductance in units of microSiemens per centimeter. The entries in the data file appear in the following columns: A. Date and Time (format: MM/DD/YYYY HH:MM; MDT, mountain daylight time) B. Specific conductance (µS/cm, microSiemens per centimeter) C. Temperature (degree Celsius) Water Quality Data The file FallWQ.csv contains sample collection date and time, pH, specific conductance, solute concentrations, and calculated charge and specific conductance balance. The entries in the water quality data file appear in the following columns: A. Sample location B. Collection Date C. Collection Time D. pH (standard units) E. Specific conductance (microSiemens per centimeter) F. Calcium concentration (milligrams per liter) G. Magnesium concentration (milligrams per liter) H. Sodium concentration (milligrams per liter) I. Potassium concentration (milligrams per liter) J. Chloride concentration (milligrams per liter) K. Sulfate concentration (milligrams per liter) L. Alkalinity (milligrams per liter as bicarbonate) M. Iron concentration (milligrams per liter) N. Silica concentration (milligrams per liter) O. Boron concentration (milligrams per liter) P. Aluminum concentration (milligrams per liter) Q. Fluoride concentration (milligrams per liter) R. Lithium concentration (milligrams per liter) S. Strontium concentration (milligrams per liter) T. Barium concentration (milligrams per liter) U. Rubidium concentration (milligrams per liter) V. Bromide concentration (milligrams per liter) W. Manganese concentration (milligrams per liter) X. Copper concentration (milligrams per liter) Y. Zinc concentration (milligrams per liter) Z. Cadmium concentration (milligrams per liter) AA. Chromium concentration (milligrams per liter) AB. Cobalt concentration (milligrams per liter) AC. Lead concentration (milligrams per liter) AD. Nickel concentration (milligrams per liter) AE. Vanadium concentration (milligrams per liter) AF. Arsenic concentration (milligrams per liter) AG. Antimony concentration (milligrams per liter) AH. Charge Balance (percent) AI. Specific Conductance Imbalance (percent) References Ball, J.W., McCleskey, R.B., and Nordstrom, D.K., 2010, Water-chemistry data for selected springs, geysers, and streams in Yellowstone National Park, Wyoming, 2006-2008: U.S. Geological Survey Open-File Report 2010-1192, 109 p. McCleskey, R.B., 2018, Calculated specific conductance using PHREEQCI: U.S. Geological Survey software release, https://doi.org/10.5066/F7M907VD. McCleskey, R.B., Nordstrom, D.K., Ryan, J.N., and Ball, J.W., 2012, A New Method of Calculating Electrical Conductivity With Applications to Natural Waters: Geochimica et Cosmochimica Acta, v. 77, p. 369-382. [http://www.sciencedirect.com/science/article/pii/S0016703711006181] USGS, 2015. A.6 Field Measurements. 6.3 Specific Electrical Conductance, National field manual for the collection of water-quality data: U.S. Geological Survey Techniques of Water-Resources Investigations, book 9, chaps. A1-A9, available online at https://water.usgs.gov/owq/FieldManual/compiled/NFM_complete.pdf.