These data are comprised of measurements of gross alpha activity, gross beta activity, and radionuclide activities (isotopic U, isotopic Th, Ra-226) in small rodent bodies. Samples were collected at non-mining and U breccia pipe mining sites in various production stages, in the Grand Canyon watershed.

These data are comprised of measurements of aluminum, iron, cobalt, nickel, copper, zinc, arsenic, selenium, molybdenum, silver, cadmium, thallium, lead, bismuth, thorium, uranium, and mercury in soil, vegetation, and small rodents. Gross alpha activity, gross beta activity, and radionuclide activities (isotopic U, isotopic Th) are also presented for vegetation and soil. Radioactivities for small rodents were previously presented at https://doi.org/10.5066/P9HARTQ4. Samples were collected at the Kanab North Mine (post-mining, pre-reclamation) in the Grand Canyon watershed.

This data release includes elemental analysis of soil samples collected at breccia-pipe uranium mines, at one undeveloped breccia-pipe uranium deposit, and at a reference site in northern Arizona. Samples were collected near the Arizona 1, Canyon, Kanab North, and Pinenut uranium mines, over the EZ2 breccia-pipe uranium deposit, and at the Little Robinson Tank reference site. Samples were collected around the Arizona 1 mine after active mining had ceased during July 2015; around and within the mine yard at the Canyon mine during mine-development activity and before active mining occurred in June 2013; around and within the mine yard at the Kanab North mine during reclamation and before reclamation was completed in June 2016; around the Pinenut mine during active mining in October 2014; directly over the EZ2 deposit before any development activity occurred during November 2015; and at the Little Robinson Tank reference site during November 2015. This data release includes data for four different types of soil samples: (type 1) incremental soil samples where more than 30 equally-spaced subsamples were collected and composited over a limited areal extent termed a decision unit and depicted generally as a trapezoidal-shaped polygon mapped within a mine yard, or surrounding a mine site; (type 2) incremental soil samples where more than 30 subsamples were collected and composited over a roughly two dimensional linear or sinuous mapped pattern following roads also termed a decision unit; (type 3) discrete integrated soil samples (Bern and others, 2019 use the term “point” for these samples) where more than 30 subsamples were collected within fenced exclosures (generally about 3 meters square) containing Big Springs Number Eight dust sampling equipment; and (type 4) integrated soil samples comprised of at least 10 subsamples collected from underneath plywood cover boards used to collect herpetofauna. Incremental samples (types 1 and 2) were collected in triplicate from the soil surface from 0-5 centimeters (cm) depth using a Multi-Incremental Sampling Tool (MIST) collecting approximately the same volume for each subsample subject to slight variation due to variable soil conditions. The volume of soil represented by each type 1 and 2 sample is termed a decision unit (DU), the areal extent of which is defined by a mapped polygonal or sinuous or linear area, and the depth of which is the 5 cm that is sampled by the MIST. Each subsample of each triplicate incremental sample was passed through a 2-millimeter sieve and composited into a clean 19-liter bucket, with each completed triplicate sample transferred to double zip-top bags for transfer to the laboratory. Integrated samples (types 3 and 4) were collected using a plastic soil scoop to collect soil from 0-5 cm depth and were composited into double zip-top plastic bags for transfer to the laboratory. Data are divided into two different data tables based upon type: types 1 and 2 are in T1_DUSamples.csv; types 3 and 4 are in T2_BSNESamples.csv. The file DataDictionary_v1.csv defines all table headings and abbreviations. Sample preparation and analytical techniques are described in the metadata file. This data release also includes location information for the approximate center points of the incremental sample polygons and linear features (decision units) and for the discrete integrated samples. Note, locations for incremental samples for decision units (sample types 1 and 2) are the approximate center of the geographical area (polygon, linear, or sinuous feature) over which the sample was collected. As such, the elemental values represent average concentrations for the sample volume collected over the entire geographic area and depth of 0-5 centimeters of each decision unit, and do not represent concentrations that would be measured in a discrete sample collected at that central location.

This data release includes elemental analysis of soil samples collected at breccia-pipe uranium mines, at one undeveloped breccia-pipe uranium deposit, and at a reference site in northern Arizona. Samples were collected near the Arizona 1, Canyon, Kanab North, and Pinenut uranium mines, over the EZ2 breccia-pipe uranium deposit, and at the Little Robinson Tank reference site. Samples were collected around the Arizona 1 mine after active mining had ceased during July 2015; around and within the mine yard at the Canyon mine during mine-development activity and before active mining occurred in June 2013; around and within the mine yard at the Kanab North mine during reclamation and before reclamation was completed in June 2016; around the Pinenut mine during active mining in October 2014; directly over the EZ2 deposit before any development activity occurred during November 2015; and at the Little Robinson Tank reference site during November 2015. This data release includes data for four different types of soil samples: (type 1) incremental soil samples where more than 30 equally-spaced subsamples were collected and composited over a limited areal extent termed a decision unit and depicted generally as a trapezoidal-shaped polygon mapped within a mine yard, or surrounding a mine site; (type 2) incremental soil samples where more than 30 subsamples were collected and composited over a roughly two dimensional linear or sinuous mapped pattern following roads also termed a decision unit; (type 3) discrete integrated soil samples (Bern and others, 2019 use the term “point” for these samples) where more than 30 subsamples were collected within fenced exclosures (generally about 3 meters square) containing Big Springs Number Eight dust sampling equipment; and (type 4) integrated soil samples comprised of at least 10 subsamples collected from underneath plywood cover boards used to collect herpetofauna. Incremental samples (types 1 and 2) were collected in triplicate from the soil surface from 0-5 centimeters (cm) depth using a Multi-Incremental Sampling Tool (MIST) collecting approximately the same volume for each subsample subject to slight variation due to variable soil conditions. The volume of soil represented by each type 1 and 2 sample is termed a decision unit (DU), the areal extent of which is defined by a mapped polygonal or sinuous or linear area, and the depth of which is the 5 cm that is sampled by the MIST. Each subsample of each triplicate incremental sample was passed through a 2-millimeter sieve and composited into a clean 19-liter bucket, with each completed triplicate sample transferred to double zip-top bags for transfer to the laboratory. Integrated samples (types 3 and 4) were collected using a plastic soil scoop to collect soil from 0-5 cm depth and were composited into double zip-top plastic bags for transfer to the laboratory. Data are divided into two different data tables based upon type: types 1 and 2 are in T1_DUSamples.csv; types 3 and 4 are in T2_BSNESamples.csv. The file DataDictionary_v1.csv defines all table headings and abbreviations. Sample preparation and analytical techniques are described in the metadata file. This data release also includes location information for the approximate center points of the incremental sample polygons and linear features (decision units) and for the discrete integrated samples. Note, locations for incremental samples for decision units (sample types 1 and 2) are the approximate center of the geographical area (polygon, linear, or sinuous feature) over which the sample was collected. As such, the elemental values represent average concentrations for the sample volume collected over the entire geographic area and depth of 0-5 centimeters of each decision unit, and do not represent concentrations that would be measured in a discrete sample collected at that central location.

These data are comprised of measurements of aluminum, iron, cobalt, nickel, copper, zinc, arsenic, selenium, molybdenum, silver, cadmium, thallium, lead, bismuth, thorium, uranium, and mercury in invertebrates, vegetation, and small rodents. Gross alpha activity, gross beta activity, and radionuclide activities (isotopic U, isotopic Th) are also presented for vegetation; radioactivities for small rodents were previously presented at https://doi.org/10.5066/P9HARTQ4. Histopathology results are given for liver and kidney lesions generally associated with metals toxicoses in small rodents. Samples were collected at the Pinenut Mine (active mining) and Arizona 1 Mine (post-production) in the Grand Canyon watershed. The non-mineralized reference sites were Little Robinson Tank and Wild Band Reservoir (Valley pocket gophers only). Results for the pre-production site (Canyon Mine) were previously presented at https://doi.org/10.5066/F7QF8R16.

The risks to wildlife and humans from uranium (U) mining to the Grand Canyon watershed are largely unknown. In addition to U, other co-occurring ore constituents contribute to risks to biological receptors depending on their toxicological profiles. This data was collected to characterize the pre-mining concentrations of total arsenic (As), cadmium (Cd), copper (Cu), lead (Pb), mercury (Hg), nickel (Ni), selenium (Se), thallium (Tl), U, and zinc (Zn); radiation levels; and histopathologies in biota (vegetation, invertebrates, amphibians, birds, and mammals) at the Canyon Mine.

Containment ponds at uranium mines in the Grand Canyon region have been suspected to pose an attractive nuisance to local wildlife in this arid landscape. To determine the presence of bird species at uranium mine openings, we surveyed the bird community in the area surrounding the mines repeatedly within one year and summarized species occurrence. We observed 35 species of birds directly using the uranium mine containment ponds including species of conservation concern, Pinyon Jay Gymnorhinus cyanocephalus and Brewer’s Sparrow Spizella breweri.

Containment ponds at uranium mines in the Grand Canyon region have been suspected to pose an attractive nuisance to local wildlife in this arid landscape. To determine the presence of bird species at uranium mine openings, we surveyed the bird community in the area surrounding the mines repeatedly within one year and summarized species occurrence. We observed 35 species of birds directly using the uranium mine containment ponds including species of conservation concern, Pinyon Jay Gymnorhinus cyanocephalus and Brewer’s Sparrow Spizella breweri.

The data consists of a summary of amphibian acoustic recordings at Canyon, Arizona 1, and Pinenut mines near the Grand Canyon. USGS is currently conducting biological surveys associated with uranium mines on federal lands in Arizona. These surveys include determining the composition of the local amphibian community. Original raw acoustic recordings used to create this summary data table are archived at Columbia Environmental Research Center.

This data release includes solid and aqueous chemical data related to a set of sequential laboratory batch experiments conducted to test and simulate the mobility of trace elements as natural waters contact ore from breccia pipe uranium (BPU) deposits located in northern Arizona. The experiments made use of aquifer-related, sedimentary rocks collected specifically for this study and archival ore material (https://doi.org/10.5066/P9VM6GKF). Data provided on solid phase materials include elemental chemistry (file “Aquifer_related_rock_elemental_chemistry_final.csv ”) and quantitative mineralogy of the sedimentary rocks (file “Aquifer_related_rock_quantitative_mineralogy_final.csv”) used in the laboratory experiments. The sedimentary rock samples were collected from surface exposures in Grand Canyon National Park. Latitude, longitude, and geologic formation information are provided for each rock sample. Aqueous data were generated from laboratory leaching experiments conducted in U.S. Geological Survey laboratories in Boulder, Colorado (file “Aqueous_samples_final.csv”). The experiments consisted of five steps that involved reacting synthetic groundwater with a subset of the sedimentary rocks and different gas mixtures to simulate natural conditions and processes. Step 1 created artificial shallow groundwater in the Grand Canyon region. Step 2 created 2 different artificial mine waters. Step 3 mimicked mine water entering a downgradient anoxic environment and encountering aquifer-related rocks. Step 4 mimicked those waters entering an oxic environment. Step 5 mimicked additional oxidation of the water in the subsurface and additional contact with aquifer-related rocks. Sample preparation, analytical techniques, and quality controls are described in the metadata file. All table attributes and abbreviations are defined in the file “Data_Dictionary_final.csv” file.