Sharon A. Fitzgerald 20201222 spreadsheet https://doi.org/10.5066/P9S4EMC7 Anna M. McKee Sharon Fitzgerald Mary J. Giorgino 2021 publication n/a US Geological Survey https://doi.org/10.3133/sir20215027 As part of the Triangle Area Water Supply Monitoring Program, the U.S. Geological Survey conducted a study to evaluate the occurrence and distribution of mercury in 14 streams and 15 reservoirs in the Triangle area of North Carolina. This Data Release contains the associated data described in the Scientific Investigations Report, "Occurrence and Distribution of Mercury in Streams and Reservoirs in the Triangle Area of North Carolina, July 2007 – June 2009". Water samples were collected seasonally between July 2007 and June 2009 for laboratory analysis of mercury, organic carbon, chlorophyll a, sulfate, and suspended sediment. Field measurements of dissolved oxygen, pH, water temperature, and specific conductance were also conducted at the sites. Bed sediment was sampled at most sites for analysis of mercury, organic carbon, and weight percent of particles smaller than sand-sized (0.0625 millimeters). Quality-assurance samples, including blanks (field, equipment, and ambient) and replicates of all analytes, were collected to quantify bias and precision of the analytical concentrations. These data were collected to evaluate the seasonal occurrence and distribution of mercury in streams and reservoirs in the Triangle area in relation to proximity of point sources of mercury. 20070701 20090630 observed Complete None planned -79.3000 -78.2500 36.5000 35.5000 North Carolina ISO 19115 Topic Category environment biota USGS Thesaurus mercury Marine Realms Information Bank (MRIB) keywords mercury analysis USGS Metadata Identifier USGS:5e1c926fe4b0ecf25c5efd00 Common geographic areas North Carolina Orange County Durham County Chatham County Wake County None. Please see 'Distribution Info' for details. None. Users are advised to read the data set's metadata thoroughly to understand appropriate use and data limitations. Sharon A Fitzgerald U.S. Geological Survey, SOUTHEAST REGION: SAWSC Raleigh Office Research Hydrologist mailing and physical

3916 Sunset Ridge Rd

Raleigh NC 27607 US 919-571-4020 919-571-4041 safitzge@usgs.gov Bias and precision were determined for all analytes. All values fall within expected ranges Data are included for sites within the study design. Water and bed sediment sample collection: Water and bed sediment sample collection and processing followed established protocols specified in the USGS National Field Manual for the Collection of Water-Quality Data (USGS, variously dated). Water samples were collected and processed following established “clean hands” protocols. In addition, equipment cleaning procedures, sample containers, and shipping procedures used in the study were those specified in the USGS National Field Manual (USGS, variously dated). Bed sediment samples were collected with an Ekman dredge at the reservoir sites. Five samples were collected and combined at each site within a small radius in order to capture small-scale variability at the site. The overlying water was removed and the upper approximately 5 centimeters (cm) of sediment was transferred to a clean glass bowl using a Teflon® beaker or Teflon® spoon. The bowl contents were homogenized prior to removing a sub-sample for analysis. For the stream sites, the upper 5 cm of sediment was collected in wadeable locations using a short corer. Teflon® sheets were used for in-situ sectioning by containing the sediments at the top and bottom of the ring. USGS, variously dated, 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: http://pubs.water.usgs.gov/twri9A: U.S. Geological Survey. 20201030 Water and bed sediment sample analysis: Discharge: Rantz, S.E., and others,, 1982, Measurement and computation of streamflow: v. 1 and 2: U.S. Geological Survey Water-Supply Paper 2175, 631 p. Temperature, dissolved oxygen, and pH: USGS, variously dated, 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: http://pubs.water.usgs.gov/twri9A: U.S. Geological Survey. Filtered and total recoverable mercury, dissolved and total organic carbon, sulfate, chlorophyll a, and pheophytin a in water samples were analyzed at the USGS National Water Quality Laboratory (NWQL) in Denver, Colorado. Suspended sediment concentration in stream samples were analyzed at the USGS Kentucky Water Science Center Sediment Laboratory in Louisville, Kentucky. Method references are as follows: Mercury, filtered and total recoverable: Garbarino, J.R., and Damrau, D.L., 2001, Methods of analysis by the US Geological Survey National Water Quality Laboratory: determination of organic plus inorganic mercury in filtered and unfiltered natural water with cold vapor-atomic fluorescence spectrometry: US Dept. of the Interior, US Geological Survey. Dissolved organic carbon: Brenton, R.W., and Arnett, T.L., 1993, Methods of analysis by the U.S. Geological Survey National Water Quality Laboratory; determination of dissolved organic carbon by UV-promoted persulfate oxidation and infrared spectrometry: Department of the Interior, U.S. Geological Survey 92-480 [Report]. Specific conductance, sulfate and suspended sediment: Fishman, M.J.E.B., and Friedman, L.C., 1989, Fishman, M. J. (Edited By), and Friedman, L. C., 1989, Methods for determination of inorganic substances in water and fluvial sediments: U.S. Geological Survey Techniques of Water-Resource Investigation 05-A1, 545 p. Chlorophyll a and pheophytin a: Arar, E.J., and Collins, G.B., 1997, Method 445.0: In vitro determination of chlorophyll a and pheophytin a in marine and freshwater algae by fluorescence, Revision 1.2: Cincinnati, OH, United States Environmental Protection Agency, Office of Research and Development. The clay and silt fraction of “fines” (particle diameter less than 63 microns) of bed sediment samples were analyzed at the USGS Georgia Sediment Partitioning Laboratory in Atlanta, Georgia for total mercury and total organic carbon. The method reference for all bed sediment analyses is as follows: Horowitz, A.J., Elrick, K.A., and Smith, J.J., 2001, Estimating suspended sediment and trace element fluxes in large river basins: methodological considerations as applied to the NASQAN programme: Hydrological processes, v. 15, no. 7, p. 1107-1132. 20201030 Water and bed sediment quality assurance and control: Bias in reported concentrations was assessed with equipment blanks, vehicle (ambient – open bottle) blanks, field blanks, and reference standards. Variability in reported concentrations was assessed with field replicates and split replicates. The various blanks reflect contamination from the sampling environment, sampling equipment, or from processing and analysis. Reference standards have a known concentration and are a measure of analytical method performance. Field replicates were used to quantify the overall variability in measured concentrations due to sampling, processing, and analysis. Split replicates reflect the variability associated only with processing and analysis. References for reference standards: NIST 2709: https://www-s.nist.gov/srmors/certificates/archives/2709.pdf MESS-3: http://www.speciation.net/Database/Materials/National-Research-Council-of-Canada-NRC--CNRC/MESS3-Marine-Sediment-Reference-Materials-for-Trace-Metals-and-other-Constituents-;i1232 USGS SGR-1B, USGS SDO-1, USGS SCO-1, USGS QLO-1, USGS GPS-2: Wolf, R.E., and Wilson, S.A., 2007, USGS Reference Materials Program: U.S. Geological Survey Fact Sheet 2007-3056, 4 p. Development of USGS Geochemical Reference Materials (https://www.usgs.gov/energy-and-minerals/mineral-resources-program/science/development-usgs-geochemical-reference?qt-science_center_objects=0#qt-science_center_objects) 20201130 Water.Environmental.Samples.csv Comma Separated Value (CSV) file containing data, "<" is less than, "E" is estimated. Producer Defined Station number A unique number used to identify sampling location Producer Defined 02085000 0209801100 Station name A unique name used to identify sampling location Producer Defined A unique name used to identify sampling location Dates Sampling date Producer Defined Aug 13 2007 June 30 2009 Times Sampling time Producer Defined 0830 1730 Discharge, instantaneous, cubic feet per second River flow in volume per time Producer Defined - No Data Producer defined 0 8290 Dissolved oxygen, water, unfiltered, milligrams per liter Concentration of dissolved oxygen (O2) in water sample Producer Defined - No Data Producer defined 0.1 13.3 pH, water, unfiltered, field, standard units pH of water sample Producer Defined - No Data Producer defined 5.7 9.1 Specific conductance, water, unfiltered, microsiemens per centimeter at 25 degrees Celsius Specific conductance of water sample Producer Defined - No Data Producer defined 31 506 Temperature, water, degrees Celsius Temperature of water sample Producer Defined - No Data Producer defined 3.7 31 Sampling depth, meters Depth measured from the surface at which sample was collected Producer Defined - No Data Producer defined 0.2 23 Sulfate, water, filtered, milligrams per liter Sulfate (SO4) concentration of filtered water sample Producer Defined - No Data Producer defined <0.18 67.4 Chlorophyll a, phytoplankton, chromatographic-fluorometric method, micrograms per liter Chlorophyll a (C55H72MgN4O5) concentration of water sample Producer Defined - No Data Producer defined 1.9 96 Pheophytin a, phytoplankton, micrograms per liter Pheophytin a (C55H74N4O5) concentration of water sample Producer Defined - No Data Producer defined 1 49.4 Mercury, water, filtered, micrograms per liter Mercury (Hg) concentration of filtered water sample Producer Defined - No Data Producer defined <0.01 0.1 Mercury, water, unfiltered, recoverable, micrograms per liter Mercury (Hg) concentration of water sample Producer Defined - No Data Producer defined <0.01 0.5 Organic carbon, water, filtered, milligrams per liter Organic carbon (C) concentration of filtered water sample Producer Defined - No Data Producer defined 2.49 18.4 Organic carbon, water, unfiltered, milligrams per liter Organic carbon (C) concentration of water sample Producer Defined - No Data Producer defined 3.1 26.8 Suspended sediment concentration, milligrams per liter Suspended sediment concentration of water sample Producer Defined - No Data Producer defined 1 419 Bed.Sediment.Environmental.Samples.csv Comma Separated Value (CSV) file containing data. Producer Defined Station number A unique number used to identify sampling location Producer Defined 02085000 0209801100 Station name A unique name used to identify sampling location Producer Defined A unique name used to identify sampling location Dates Sampling date Producer Defined Apr 1 2009 May 28 2009 Times Sampling time Producer Defined 0915 1300 Mercury, bed sediment, total digestion, dry weight, milligrams per kilogram Mercury (Hg) concentration of bed sediment sample Producer Defined 0.02 0.82 Organic carbon, bed sediment, total, dry weight, percent Organic carbon (C) concentration of bed sediment sample Producer Defined 0.2 4.1 Bed sediment, wet sieved, sieve diameter, percent smaller than 0.0625 millimeters Weight percent of sediment particles smaller than sand-sized (0.0625 millimeters) of bed sediment sample Producer Defined 1 99 Water.Blanks.csv Comma Separated Value (CSV) file containing data, "<" is less than, "E" is estimated. Producer Defined Station number A unique number used to identify sampling location Producer Defined 02086569 370010102 Station name A unique name used to identify sampling location Producer Defined A unique name used to identify sampling location Date Sampling date Producer Defined Aug 28 2007 June 26 2009 Time Sampling time Producer Defined 1000 1430 Blank type Type of blank Producer Defined Field A blank solution that is subjected to all aspects of sample collection, field-processing preservation, transportation, and laboratory handling as an environmental sample. Producer defined Equipment A blank solution that is processed through some or all equipment used for collecting and processing an environmental sample (similar to a field blank but normally done in the more controlled conditions of the office than the field). Producer defined Ambient A blank solution that is put in the same type of bottle used for an environmental sample, kept with the set of sample bottles before sample collection, and opened at the site and exposed to the ambient conditions. Producer defined Sulfate, water, filtered, milligrams per liter Sulfate (SO4) concentration of filtered water sample Producer Defined - No data Producer defined <0.18 <0.18 Mercury, water, filtered, micrograms per liter Mercury (Hg) concentration of filtered water sample Producer Defined - No data Producer defined <0.010 <0.010 Mercury, water, unfiltered, recoverable, micrograms per liter Mercury (Hg) concentration of water sample Producer Defined - No data Producer defined <0.010 <0.010 Organic carbon, water, filtered, milligrams per liter Organic carbon (C) concentration of filtered water sample Producer Defined - No data Producer defined <0.40 1.07 Water.Environmental.Replicate.Pairs.csv Comma Separated Value (CSV) file containing data, "<" is less than, "E" is estimated. Producer Defined Station number A unique number used to identify sampling location Producer Defined 02085000 0209801100 Station name A unique name used to identify sampling location Producer Defined A unique name used to identify sampling location Date Sampling date Producer Defined Apr 28 2008 Oct 5 2007 Time Sampling time Producer Defined 0830 1446 Sample type Type of sample Producer Defined Environmental The main sample Producer defined Replicate One or more additional samples collected simultaneously with two or more samplers or by using one sampler and alternating collection of samples into two or more compositing containers. Producer defined Sulfate, water, filtered, milligrams per liter Sulfate (SO4) concentration of water sample Producer Defined - No data Producer defined 2.72 23.5 Chlorophyll a, phytoplankton, chromatographic-fluorometric method, micrograms per liter Chlorophyll a (C55H72MgN4O5) concentration of water sample Producer Defined - No data Producer defined 1.6 96 Pheophytin a, phytoplankton, micrograms per liter Pheophytin a (C55H74N4O5) concentration of water sample Producer Defined - No data Producer defined 0.7 31.2 Mercury, water, filtered, micrograms per liter Mercury (Hg) concentration of filtered water sample Producer Defined <0.010 0.023 Mercury, water, unfiltered, recoverable, micrograms per liter Mercury (Hg) concentration of water sample Producer Defined - No data Producer defined <0.010 0.073 Organic carbon, water, filtered, milligrams per liter Organic carbon (C) concentration of filtered water sample Producer Defined - No data Producer defined 4.32 11.4 Organic carbon, water, unfiltered, milligrams per liter Organic carbon (C) concentration of water sample Producer Defined - No data Producer defined 5 15.3 Suspended sediment concentration, milligrams per liter Suspended sediment concentration of water sample Producer Defined - No data Producer defined 4 8 Bed.Sediment.Environmental.Replicate.Pairs.csv Comma Separated Value (CSV) file containing data. Producer Defined Station number A unique number used to identify sampling location Producer Defined 02087588 0209699999 Station name A unique name used to identify sampling location Producer Defined A unique name used to identify sampling location Date Sampling date Producer Defined Apr 16 2009 Apr 22 2009 Time Sampling time Producer Defined 1100 1115 Sample type Type of sample Producer Defined Environmental The main sample Producer defined Replicate One or more additional samples collected simultaneously with two or more samplers or by using one sampler and alternating collection of samples into two or more compositing containers. Producer defined Mercury, bed sediment, total digestion, dry weight, milligrams per kilogram Mercury (Hg) concentration of bed sediment sample Producer Defined 0.03 0.1 Organic carbon, bed sediment, total, dry weight, percent Organic carbon (C) concentration of bed sediment sample Producer Defined 1.7 3.8 Bed sediment, wet sieved, sieve diameter, percent smaller than 0.0625 millimeters Weight percent of sediment particles smaller than sand-sized (0.0625 millimeters) of bed sediment sample Producer Defined 71 94 Bed.Sediment.Standard.Reference.Material.Recovery.csv Comma Separated Value (CSV) file containing data. Producer Defined Reference material Unique alphanumeric identifier for reference material Producer Defined Unique alphanumeric identifier for reference material Reported mercury concentration in milligrams per kilogram Mercury (Hg) concentration reported for the reference material Producer Defined - No data Producer defined 0.01 1.4 Reported mercury concentration range (plus or minus) in milligrams per kilogram Mercury (Hg) concentration range reported for the reference material Producer Defined - No data Producer defined 0.01 0.08 Found mercury concentration in milligrams per kilogram Mercury (Hg) concentration found for the reference material Producer Defined - No data Producer defined 0.02 1.4 Absolute difference between reported and found mercury concentrations in milligrams per kilogram Absolute difference between reported and found mercury (Hg) concentrations in milligrams per kilogram Producer Defined - No data Producer defined 0 0.07 Relative percent difference between reported and found mercury concentrations Relative percent difference between reported and found mercury (Hg) concentrations Producer Defined - No data Producer defined 0 67 Reported total organic carbon concentration in weight percent Total organic carbon (TOC) concentration reported for the reference material Producer Defined <0.1 28 Reported total organic carbon concentration range (plus or minus) in weight percent Total organic carbon (TOC) concentration range reported for the reference material Producer Defined - No data Producer defined 0.1 0.44 Found total organic carbon concentration in weight percent Total organic carbon (TOC) concentration found for the reference material Producer Defined <0.1 26 Absolute difference between reported and found total organic carbon concentrations in weight percent Absolute difference between reported and found total organic carbon (TOC) concentrations in weight percent Producer Defined - No data Producer defined 0 2 Relative percent difference between reported and found total organic carbon concentrations Relative percent difference between reported and found total organic carbon (TOC) concentrations Producer Defined - No data Producer defined 0 18 Leading and following zeros on some numeric entries may have been omitted upon file conversion. 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Denver CO 80225 United States 1-888-275-8747 sciencebase@usgs.gov Unless otherwise stated, all data, metadata and related materials are considered to satisfy the quality standards relative to the purpose for which the data were collected. Although these data and associated metadata have been reviewed for accuracy and completeness and approved for release by the U.S. Geological Survey (USGS), no warranty expressed or implied is made regarding the display or utility of the data on any other system or for general or scientific purposes, nor shall the act of distribution constitute any such warranty. Digital Data https://doi.org/10.5066/P9S4EMC7 None 20201222 Sharon Fitzgerald USGS - SAWSC Research Hydrologist mailing and physical

3916 Sunset Ridge Road

Raleigh North Carolina 27607 USA 919.571.4020 919.571.4041 safitzge@usgs.gov FGDC Biological Data Profile of the Content Standard for Digital Geospatial Metadata FGDC-STD-001.1-1999