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 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).

These data represent mercury (Hg), filtered total Hg (FTHg), filtered methylmercury (FMHg), particulate total Hg (PTHg), particulate methylmercury (PMHg), total mercury (THg), dissolved organic carbon (DOC) and total organic carbon (TOC) concentrations in surface water samples collected on Bad River Tribal lands. Several samples were collected at multiple locations on the Bad River and Tyler Forks Creek, and one location on Bull Gus Creek. Additionally, one sample was collected at each of four unknown locations on four Bad River tributaries and two samples at a lake of unknown location. All samples were collected during 2006 to 2016. Neither the collection of water samples nor the Hg analyses were performed by the U.S. Geological Survey, New York Water Science Center.

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.

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.

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.

Measurements of Mercury collected at Putah Creek Below Monticello Dam. Currently collected twice a year, previously collected quarterly. Access further information for this data set by contacting Bureau of Reclamation, California-Great Basin Region, Environmental Affairs Division (CGB-157). See ResultAttributes for STAFF_GAUGE, SMPL_DEPTH, SMPL_CATEGORY_NAME, METHOD_CODE, RESULT_RL, RESULT_RL-UNIT_STD_NAME, RESULT_MDL, RESULT_MDL-UNIT_STD_NAME, USBR_QA_SUBTYPE_NAME, USBR_QULFR_DESCRIPTION. STAFF_GAUGE is the water height in decimal feet measured by gauge (e.g., 15.2). SMPL_DEPTH is the vertical depth at which sample is collected (e.g., 0 - 15 cm). For water samples: depth below water/air interface. For sediment and soil samples: depth below water/solid or air/solid interface. SMPL_CATEGORY_NAME is the category type of sample (e.g., Composite). METHOD_CODE is the name of method used to obtain result (e.g., EPA 200.8). RESULT_RL is the result reporting limit (accounting for dilution) (e.g., 0.02). RESULT_RL-UNIT_STD_NAME is the unit associated with RESULT_RL (e.g., mg/L). RESULT_MDL is the result method detection limit (e.g., 0.007). RESULT_MDL-UNIT_STD_NAME is the unit associated with RESULT_MDL (e.g., mg/L). USBR_QA_SUBTYPE_NAME is the quality control type of the sample (e.g., USBR_BLANK_SPIKE). USBR_QULFR_DESCRIPTION is the quality assurance description (if any) (e.g., Result may have a high bias.).

Data used to create figures in the manuscript. This dataset is associated with the following publication: Eckley, C.S., T.P. Luxton, B. Stanfield, A. Baldwin, J. Holloway, J. McKernan, and M.G. Johnson. Effect of organic matter concentration and characteristics on mercury mobilization and methylmercury production at an abandoned mine site. ENVIRONMENTAL POLLUTION. Elsevier Science Ltd, New York, NY, USA, 271: 116369, (2021).