The data set contains a summary of all measurements that were collected at the cottage grove reservoir over the time period of the study. This dataset is associated with the following publication: Eckley, C., T. Luxton, J. Goetz, and J. McKernan. Water-level fluctuations influence sediment porewater chemistry and methylmercury production in a flood-control reservoir.. David Carpenter, and Eddy Zeng ENVIRONMENTAL POLLUTION. Elsevier Science Ltd, New York, NY, USA, 222: 32-41, (2017).

the data set contains a summary of all measurements that were collected at the cottage grove reservoir over the time period of the study. This dataset is associated with the following publication: Eckley , C., T. Luxton , J. McKernan , J. Goetz , and J. Goulet. Influence of Reservoir Water-Level Fluctuations on Mercury Methylation Downstream of the Historic Black Butte Mercury Mine, OR. Michael Kersten APPLIED GEOCHEMISTRY. Elsevier Science Ltd, New York, NY, USA, 61: 284-293, (2015). NOTE: This dataset has been removed from public access due to revocation. Please refer inquiries regarding this dataset to the listed contact person.

the data set contains a summary of all measurements that were collected at the cottage grove reservoir over the time period of the study. This dataset is associated with the following publication: Eckley , C., T. Luxton , J. McKernan , J. Goetz , and J. Goulet. Influence of Reservoir Water-Level Fluctuations on Mercury Methylation Downstream of the Historic Black Butte Mercury Mine, OR. Michael Kersten APPLIED GEOCHEMISTRY. Elsevier Science Ltd, New York, NY, USA, 61: 284-293, (2015). NOTE: This dataset has been removed from public access due to revocation. Please refer inquiries regarding this dataset to the listed contact person.

The data set contains the raw data used to develop the figures and tables associated with the published manuscript. This dataset is associated with the following publication: Eckley , C., T. Luxton , J. McKernan , J. Goetz , and J. Goulet. Influence of Reservoir Water-Level Fluctuations on Mercury Methylation Downstream of the Historic Black Butte Mercury Mine, OR. Michael Kersten APPLIED GEOCHEMISTRY. Elsevier Science Ltd, New York, NY, USA, 61: 284-293, (2015).

The data set contains the raw data used to develop the figures and tables associated with the published manuscript. This dataset is associated with the following publication: Eckley , C., T. Luxton , J. McKernan , J. Goetz , and J. Goulet. Influence of Reservoir Water-Level Fluctuations on Mercury Methylation Downstream of the Historic Black Butte Mercury Mine, OR. Michael Kersten APPLIED GEOCHEMISTRY. Elsevier Science Ltd, New York, NY, USA, 61: 284-293, (2015).

The current data entry contains the raw data that was used to create the figures and tables in the publication. This dataset is associated with the following publication: Millard, G., C.S. Eckley, T.P. Luxton, D. Krabbenhoft, J. Goetz, J. McKernan, and J. DeWild. Evaluating the influence of seasonal stratification on mercury methylation rates in the water column and sediment in a contaminated section of a western U.S.A. reservoir. ENVIRONMENTAL POLLUTION. Elsevier Science Ltd, New York, NY, USA, 316: 120485, (2023).

The current data entry contains the raw data that was used to create the figures and tables in the publication. This dataset is associated with the following publication: Millard, G., C.S. Eckley, T.P. Luxton, D. Krabbenhoft, J. Goetz, J. McKernan, and J. DeWild. Evaluating the influence of seasonal stratification on mercury methylation rates in the water column and sediment in a contaminated section of a western U.S.A. reservoir. ENVIRONMENTAL POLLUTION. Elsevier Science Ltd, New York, NY, USA, 316: 120485, (2023).

Data includes fine‑scale (1.5 cm minimum resolution) vertical solute concentrations for filtered methylmercury (ng/L), filtered total mercury (ng/L), dissolved organic carbon (mg/L), and dissolved chloride (micromole/L) in SixMile Brook, New York and McTier Creek, South Carolina. Vertical solute data were assessed one time at one site in each stream in 2009, at edge-of-water (margin) and center-of-channel (channel) using two mini-piezometer (USGS MINIPOINT) devices (seven 0.325 cm stainless steel tubes, 0.8 cm screened interval). Each MINIPOINT device was installed with sampling points in surface water and at approximately 1.5, 4.5, 7.5, 12.5, 17.5, 30, and 60 cm below the bed-sediment/surface-water interface.

This dataset includes water-quality and sediment data for 647 environmental samples collected at 53 surface-water sites in Cache Creek (Cache C) watershed, Yolo County, California, between December 2009 and April 2019, and data for 190 associated quality-control samples (replicates and blanks). About 90 percent of the samples were collected at the following six primary sites that were sampled most frequently, and the other 39 extra sites were sampled only 1-5 times each. In addition, continuous turbidity measurements were made at 8 sites to aid with the calibration of turbidity measurements. The sites Cache C at Rumsey (11451800), Cache C at Yolo (11452500), and CCSB Inlet at Rd 102 (11452600) are upstream of the Cache C Settling Basin (CCSB); all other sites are in the CCSB and are shown on the map included in this data release. NWIS_Site_Number: Field_ID: 11451800 Cache C at Rumsey 11452500 Cache C at Yolo 11452600 CCSB Inlet at Rd.102 11452900 CCSB Outlet 11452800 CCSB S. Abutment Spillway 384115121402501 CCSB N. Abutment Spillway Constituents analyzed include total mercury and methylmercury in dissolved and particulate forms, reactive divalent mercury in particulate form, suspended sediment, dissolved organic carbon, and absorption-fluorescence data for dissolved organic matter. The grain-size distribution of suspended sediment in selected samples is also reported. Six data tables and a Data Dictionary were prepared for this data release. All tables are provided as machine readable tab-delimited text (*.txt) files and as Excel formatted (*.xlsx) files. The data dictionary provides definitions and details presented in the data tables, including analytical methods citations. Two of the six data tables present and summarize quality control results collected for the study.

This dataset includes the field measurements and laboratory analyses of surface water, seston, and sediment collected from Lake Powell, within Glen Canyon National Recreation area (GLCA), during high flow (May-June 2014) and low flow (August 2015) conditions. The study area includes 12-13 sampling sites that follow a transect spanning the entire length of the reservoir from the Colorado River inflow to the Glen Canyon dam, as well as the San Juan River arm, the Escalante River arm and West Canyon. Bed sediment samples were analyzed for mercury speciation, methylmercury production and degradation rates, total reduced sulfur, iron speciation, organic content, and 16S rRNA gene templates as a proxy for microbial abundances. Water samples were collected from 3-5 depths at each site and analyzed for: total mercury (filtered and particulate), methylmercury (filtered and particulate), dissolved organic and inorganic carbon with 13C isotopic ratios, nutrients, anions, cations, trace metals, particulate carbon (with 13C isotopic ratios) and particulate nitrogen (with 15N isotopic ratios). Water quality sonde (EXO) field measurements included specific conductivity, temperature, pH, dissolved oxygen, fluorescent dissolved organic matter, chlorophyll, and turbidity. Fish samples were also collected during November 2014 from Good Hope Bay (upper reservoir), Wahweap Bay (lower reservoir), and the San Juan arm and assayed for total mercury for comparison with previous striped bass samples collected by the state of Utah. There are nine files (*.csv) in this dataset: 1) data dictionary ; 2) sediment data; 3) water data; 4) seston data; 5) fish data; 6) EXO main channel profile data ; 7) EXO off channel profile data; 8) quality assurance data; and 9) molecular data.