Krishangi Groover
Krishangi Groover - California Water Science Center
Science and Products
Selenium Cycling in Salton Sea Wetlands
The effect of selenium toxicity on wildlife has been known for more than 50 years. This issue drew particular attention in the 1980s when embryo deformity and mortality was observed in birds at a wildlife refuge in California. Harmful effects from selenium were determined to be connected to irrigation drainage water. As a result, an effort began to monitor levels of selenium in irrigation drainage...
Water and sediment data used to evaluate selenium hazards in the Salton Sea ecosystem
Due to declining water levels and increasing salinity in the Salton Sea which may increase the hazards to wildlife, the U.S. Geological Survey and U.S. Bureau of Reclamation are re-evaluating selenium concentrations in the region. As part of this work, selenium concentrations in water and sediment samples and selected other inorganic constituents were compiled from published reports, public databa
Ground-based transient electromagnetic data and resistivity models at selected sites of the California Central Coast and San Joaquin Valley 2019
Ground-based transient electromagnetic (TEM) data were acquired by the U.S. Geological Survey (USGS) at 16 locations of California’s southwestern San Joaquin Valley and Central Coast regions to define the electrical resistivity structure of hydrogeologic materials. Data were acquired using the ABEM WalkTEM system (Guideline Geo Ab, Sundbyberg, Sweden). TEM data were processed and numerically inver
Hydrologic data in Hinkley and Water Valleys, San Bernardino County, California, 2015-2018
Data were collected to help define hydrologic controls on groundwater movement as part of a U.S. Geological Survey (USGS) study on background concentrations of hexavalent chromium in groundwater aquifers near Hinkley, California. Most data associated with the background study are available through the National Water Information System (NWIS) website, and GeoLog Locator. This product is intended to
Electrical Resistivity Tomography Data at Elizabeth Lake, Los Angeles County, California, 2019
The Santa Clara River Lakes, located along the San Andreas fault 19 miles northwest of Palmdale, California, were placed on the state?s ?303(d) List? or ?Impaired Water List? in 1996 for eutrophic conditions, high pH, and low dissolved oxygen. In 2016, the state adopted a Total Maximum Daily Load (TMDL) for nutrients (nitrogen and phosphorus) in the Santa Clara River Lakes. This study focuses on t
Surface geophysics investigations at Edwards Air Force Research Laboratory, Antelope Valley, California, 2018
The Air Force Research Laboratory (AFRL) is about 7 kilometers southwest of Boron, California, and covers 320 square kilometers of Edwards Air Force Base. The AFRL consists of 12 facilities for testing full-size rocket engines, engine components, and liquid and solid propellants. The historical release of contaminants from rocket test stands, evaporation ponds, burn pits, catch basins, and leaking
Unsaturated zone soil properties near a dry well and Four-plex baseball field, Fort Irwin National Training Center, San Bernardino County, California, 2019-2020
The U.S. Army Fort Irwin National Training Center (NTC), approximately 35 miles north-northeast of Barstow, California, obtains all of its potable water supply from three groundwater basins (Irwin, Langford, and Bicycle Basins) within the NTC boundaries. In these basins, groundwater withdrawals exceed natural recharge, resulting in water-level declines. However, managed aquifer recharge using recy
Irrigated field characterization at Fort Irwin National Training Center, San Bernardino County, California, 2018-2020
The U.S. Army Fort Irwin National Training Center (NTC), approximately 35 miles north-northeast of Barstow, California, obtains all of its potable water supply from three groundwater basins (Irwin, Langford, and Bicycle Basins) within the NTC boundaries. In these basins, groundwater withdrawals exceed natural recharge, resulting in water-level declines. However, managed aquifer recharge using trea
Electrical Resistivity Tomography in the Anza-Terwilliger Valley, Riverside County, California 2018
The Cahuilla Valley and Terwilliger Valley groundwater basins, 9-006 and 7-026 respectively (California Department of Water Resources 2016) located approximately 25 miles southwest of Palm Springs, are the sole-source for groundwater supply for the rural disadvantaged community and two Native American Tribes, the Ramona Band of Cahuilla and the Cahuilla,. The characteristics and sustainable yield
Groundwater-quality data in the Mojave Basin Shallow Aquifer Study Unit, 2018: Results from the California GAMA Priority Basin Project
The U.S. Geological Survey collected groundwater samples from 49 wells used for domestic and small system drinking water supplies and 10 monitoring wells in San Bernardino County, California in 2018. The wells were sampled for the Mojave Basin (MOBS) Shallow Aquifer Study Unit of the California State Water Resources Control Board Groundwater Ambient Monitoring and Assessment (GAMA) Program Priorit
Field portable X-ray fluorescence and associated quality control data for the western Mojave Desert, San Bernardino County, California
These data on the concentrations of 27 selected elements were collected using a field portable (handheld) X-ray fluorescence (pXRF) instrument (Groover and Izbicki, 2016) equipped with a 4-watt Ta/Au X-ray tube on samples of 1) surficial alluvium, 2) rock, and 3) archived core material and drill cuttings from monitoring wells across an approximately 14,300 square kilometer area in the western part
Filter Total Items: 20
Status and understanding of groundwater quality in the Mojave Basin Domestic-Supply Aquifer study unit, 2018—California GAMA Priority Basin Project
Groundwater quality in the western part of the Mojave Desert in San Bernardino County, California, was investigated in 2018 as part of the California State Water Resources Control Board Groundwater Ambient Monitoring and Assessment Program Priority Basin Project. The Mojave Basin Domestic-Supply Aquifer study unit (MOBS) region was divided into two study areas—floodplain and regional—to assess dif
Authors
Krishangi D. Groover, Miranda S. Fram, Zeno F. Levy
Nutrient chemistry in the Elizabeth Lake subwatershed—Effects of onsite wastewater treatment systems on groundwater and lake water quality, Los Angeles County, California
Nutrient (nitrogen [N] and phosphorus [P] chemistry) downgradient from onsite wastewater treatment system (OWTS) was evaluated with a groundwater study in the area surrounding Elizabeth Lake, the largest of three sag lakes within the Santa Clara River watershed of Los Angeles County, California.Elizabeth Lake is listed on the “303 (d) Impaired Waters List” for excess nutrients and is downgradient
Authors
Adelia M McGregor, Joseph L. Domagalski, Krishangi D. Groover, Angela M. Hansen, Anthony A. Brown
Arsenic, chromium, uranium, and vanadium in rock, alluvium, and groundwater, Mojave River and Morongo Areas, western Mojave Desert, southern California
Trace elements within groundwater that originate from aquifer materials and pose potential public-health hazards if consumed are known as geogenic contaminants. The geogenic contaminants arsenic, chromium, and vanadium can form negatively charged ions with oxygen known as oxyanions. Uranium complexes with bicarbonate and carbonate to form negatively charged ions having aqueous chemistry similar to
Authors
John A. Izbicki, Krishangi D. Groover, Whitney A. Seymour
Selenium hazards in the Salton Sea environment—Summary of current knowledge to inform future wetland management
Quaternary marine and continental shales in the western United States are sources of selenium that can be loaded into the aquatic environment through mining, agricultural, and energy production processes. The mobilization of selenium from shales through agricultural irrigation has been recognized since the 1930s; however, discovery of deformities in birds and other wildlife using agricultural habi
Authors
Michael R. Rosen, Susan E.W. De La Cruz, Krishangi D. Groover, Isa Woo, Sarah A. Roberts, Melanie J. Davis, Cristiana Y. Antonino
Natural and anthropogenic hexavalent chromium, Cr(VI), in groundwater near a mapped plume, Hinkley, California
The Pacific Gas and Electric Company (PG&E) Hinkley compressor station, in the Mojave Desert, 80 miles northeast of Los Angeles, California, is used to compress natural gas as it is transported through a pipeline from Texas to California. Between 1952 and 1964, cooling water was treated with a compound containing hexavalent chromium, Cr(VI), to prevent corrosion of machinery within the compressor
Authors
John A. Izbicki, Krishangi D. Groover, Whitney A. Seymour, David M. Miller, John G. Warden, Laurence G. Miller
Predevelopment water levels, groundwater recharge, and selected hydrologic properties of aquifer materials, Hinkley and Water Valleys, California
Hydrologic and geophysical data were collected to support updates to an existing groundwater-flow model of Hinkley Valley, California, in the Mojave Desert about 80 miles northeast of Los Angeles, California. These data provide information on predevelopment (pre-1930) water levels, groundwater recharge, and selected hydrologic properties of aquifer materials.A predevelopment groundwater-level map,
Authors
Krishangi D. Groover, John A. Izbicki, Whitney A. Seymour, Anthony A. Brown, Randall E. Bayless, Carole D. Johnson, Katherine L. Pappas, Gregory A. Smith, Dennis A. Clark, Joshua Larsen, Meghan C. Dick, Lorraine E. Flint, Christina L. Stamos, John G. Warden
Introduction to study area hydrogeology, chromium sources, site history, and purpose of study
Between 1952 and 1964, hexavalent chromium, Cr(VI), was released into groundwater from the Pacific Gas and Electric Company (PG&E) Hinkley compressor station in the Mojave Desert 80 miles (mi) northeast of Los Angeles, California. Remediation began in 1992, and in 2010, site cleanup was projected to require between 10 and 95 years and was expected to cost between $36 and $176 million. A 2007 PG&E
Authors
John A. Izbicki, Krishangi D. Groover, David M. Miller, Whitney A. Seymour, John G. Warden, Laurence G. Miller
Survey of chromium and selected element concentrations in rock, alluvium, and core material
Between 1952 and 1964, hexavalent chromium, Cr(VI), was released into groundwater from the Pacific Gas and Electric Company (PG&E) compressor station in Hinkley, California, in the western Mojave Desert 80 miles northeast of Los Angeles, California. In 2015, the extent of anthropogenic Cr(VI) in groundwater in Hinkley and Water Valleys was uncertain, and some Cr(VI) in groundwater may be naturally
Authors
John A. Izbicki, Krishangi D. Groover
Chromium in minerals and selected aquifer materials
Between 1952 and 1964, hexavalent chromium, Cr(VI), was released into groundwater from a Pacific Gas and Electric Company (PG&E) compressor station in Hinkley, California, in the western Mojave Desert 80 miles northeast of Los Angeles, California. In 2015, the extent of anthropogenic Cr(VI) in groundwater in Hinkley and Water Valleys was uncertain, but some Cr(VI) in groundwater may be naturally o
Authors
Krishangi D. Groover, John A. Izbicki, William Benzel, Jean Morrison, Andrea L. Foster
Evaluation of natural and anthropogenic (human-made) hexavalent chromium
Hexavalent chromium, Cr(VI), was released between 1952 and 1964 from the Pacific Gas and Electric Company (PG&E) Hinkley compressor station, in the Mojave Desert about 80 miles northeast of Los Angeles, California. Geologic, geochemical, and hydrologic data from more than 100 wells collected between March 2015 and November 2017 were interpreted using a summative-scale analysis to define the extent
Authors
John A. Izbicki, John G. Warden, Krishangi D. Groover, Whitney A. Seymour
Sequestration and reoxidation of chromium in experimental microcosms
Groundwater containing hexavalent chromium, Cr(VI), downgradient from the Pacific Gas and Electric Company (PG&E) Hinkley compressor station in the Mojave Desert, 80 miles northeast of Los Angeles, California, is undergoing bioremediation using added ethanol as a reductant in a volume of the aquifer defined as the in situ reactive zone (IRZ). This treatment reduces Cr(VI) to trivalent chromium, Cr
Authors
Laurence G. Miller, Callum E. Bobb, Andrea L. Foster, Emily G. Wright, Stacy C. Bennett, Krishangi D. Groover, John A. Izbicki
Summary and conclusions
Executive SummaryChromium concentrations in rock and aquifer material in Hinkley and Water Valleys in the Mojave Desert, 80 miles northeast of Los Angeles, California, are generally low compared to the average chromium concentration of 185 milligrams per kilogram (mg/kg) in the average bulk continental crust. Chromium concentrations in felsic, coarse-textured “Mojave-type” deposits, composed of Mo
Authors
John A. Izbicki, Krishangi D. Groover, Whitney A. Seymour, David M. Miller, John G. Warden, Laurence G. Miller
Science and Products
Selenium Cycling in Salton Sea Wetlands
The effect of selenium toxicity on wildlife has been known for more than 50 years. This issue drew particular attention in the 1980s when embryo deformity and mortality was observed in birds at a wildlife refuge in California. Harmful effects from selenium were determined to be connected to irrigation drainage water. As a result, an effort began to monitor levels of selenium in irrigation drainage...
Water and sediment data used to evaluate selenium hazards in the Salton Sea ecosystem
Due to declining water levels and increasing salinity in the Salton Sea which may increase the hazards to wildlife, the U.S. Geological Survey and U.S. Bureau of Reclamation are re-evaluating selenium concentrations in the region. As part of this work, selenium concentrations in water and sediment samples and selected other inorganic constituents were compiled from published reports, public databa
Ground-based transient electromagnetic data and resistivity models at selected sites of the California Central Coast and San Joaquin Valley 2019
Ground-based transient electromagnetic (TEM) data were acquired by the U.S. Geological Survey (USGS) at 16 locations of California’s southwestern San Joaquin Valley and Central Coast regions to define the electrical resistivity structure of hydrogeologic materials. Data were acquired using the ABEM WalkTEM system (Guideline Geo Ab, Sundbyberg, Sweden). TEM data were processed and numerically inver
Hydrologic data in Hinkley and Water Valleys, San Bernardino County, California, 2015-2018
Data were collected to help define hydrologic controls on groundwater movement as part of a U.S. Geological Survey (USGS) study on background concentrations of hexavalent chromium in groundwater aquifers near Hinkley, California. Most data associated with the background study are available through the National Water Information System (NWIS) website, and GeoLog Locator. This product is intended to
Electrical Resistivity Tomography Data at Elizabeth Lake, Los Angeles County, California, 2019
The Santa Clara River Lakes, located along the San Andreas fault 19 miles northwest of Palmdale, California, were placed on the state?s ?303(d) List? or ?Impaired Water List? in 1996 for eutrophic conditions, high pH, and low dissolved oxygen. In 2016, the state adopted a Total Maximum Daily Load (TMDL) for nutrients (nitrogen and phosphorus) in the Santa Clara River Lakes. This study focuses on t
Surface geophysics investigations at Edwards Air Force Research Laboratory, Antelope Valley, California, 2018
The Air Force Research Laboratory (AFRL) is about 7 kilometers southwest of Boron, California, and covers 320 square kilometers of Edwards Air Force Base. The AFRL consists of 12 facilities for testing full-size rocket engines, engine components, and liquid and solid propellants. The historical release of contaminants from rocket test stands, evaporation ponds, burn pits, catch basins, and leaking
Unsaturated zone soil properties near a dry well and Four-plex baseball field, Fort Irwin National Training Center, San Bernardino County, California, 2019-2020
The U.S. Army Fort Irwin National Training Center (NTC), approximately 35 miles north-northeast of Barstow, California, obtains all of its potable water supply from three groundwater basins (Irwin, Langford, and Bicycle Basins) within the NTC boundaries. In these basins, groundwater withdrawals exceed natural recharge, resulting in water-level declines. However, managed aquifer recharge using recy
Irrigated field characterization at Fort Irwin National Training Center, San Bernardino County, California, 2018-2020
The U.S. Army Fort Irwin National Training Center (NTC), approximately 35 miles north-northeast of Barstow, California, obtains all of its potable water supply from three groundwater basins (Irwin, Langford, and Bicycle Basins) within the NTC boundaries. In these basins, groundwater withdrawals exceed natural recharge, resulting in water-level declines. However, managed aquifer recharge using trea
Electrical Resistivity Tomography in the Anza-Terwilliger Valley, Riverside County, California 2018
The Cahuilla Valley and Terwilliger Valley groundwater basins, 9-006 and 7-026 respectively (California Department of Water Resources 2016) located approximately 25 miles southwest of Palm Springs, are the sole-source for groundwater supply for the rural disadvantaged community and two Native American Tribes, the Ramona Band of Cahuilla and the Cahuilla,. The characteristics and sustainable yield
Groundwater-quality data in the Mojave Basin Shallow Aquifer Study Unit, 2018: Results from the California GAMA Priority Basin Project
The U.S. Geological Survey collected groundwater samples from 49 wells used for domestic and small system drinking water supplies and 10 monitoring wells in San Bernardino County, California in 2018. The wells were sampled for the Mojave Basin (MOBS) Shallow Aquifer Study Unit of the California State Water Resources Control Board Groundwater Ambient Monitoring and Assessment (GAMA) Program Priorit
Field portable X-ray fluorescence and associated quality control data for the western Mojave Desert, San Bernardino County, California
These data on the concentrations of 27 selected elements were collected using a field portable (handheld) X-ray fluorescence (pXRF) instrument (Groover and Izbicki, 2016) equipped with a 4-watt Ta/Au X-ray tube on samples of 1) surficial alluvium, 2) rock, and 3) archived core material and drill cuttings from monitoring wells across an approximately 14,300 square kilometer area in the western part
Filter Total Items: 20
Status and understanding of groundwater quality in the Mojave Basin Domestic-Supply Aquifer study unit, 2018—California GAMA Priority Basin Project
Groundwater quality in the western part of the Mojave Desert in San Bernardino County, California, was investigated in 2018 as part of the California State Water Resources Control Board Groundwater Ambient Monitoring and Assessment Program Priority Basin Project. The Mojave Basin Domestic-Supply Aquifer study unit (MOBS) region was divided into two study areas—floodplain and regional—to assess dif
Authors
Krishangi D. Groover, Miranda S. Fram, Zeno F. Levy
Nutrient chemistry in the Elizabeth Lake subwatershed—Effects of onsite wastewater treatment systems on groundwater and lake water quality, Los Angeles County, California
Nutrient (nitrogen [N] and phosphorus [P] chemistry) downgradient from onsite wastewater treatment system (OWTS) was evaluated with a groundwater study in the area surrounding Elizabeth Lake, the largest of three sag lakes within the Santa Clara River watershed of Los Angeles County, California.Elizabeth Lake is listed on the “303 (d) Impaired Waters List” for excess nutrients and is downgradient
Authors
Adelia M McGregor, Joseph L. Domagalski, Krishangi D. Groover, Angela M. Hansen, Anthony A. Brown
Arsenic, chromium, uranium, and vanadium in rock, alluvium, and groundwater, Mojave River and Morongo Areas, western Mojave Desert, southern California
Trace elements within groundwater that originate from aquifer materials and pose potential public-health hazards if consumed are known as geogenic contaminants. The geogenic contaminants arsenic, chromium, and vanadium can form negatively charged ions with oxygen known as oxyanions. Uranium complexes with bicarbonate and carbonate to form negatively charged ions having aqueous chemistry similar to
Authors
John A. Izbicki, Krishangi D. Groover, Whitney A. Seymour
Selenium hazards in the Salton Sea environment—Summary of current knowledge to inform future wetland management
Quaternary marine and continental shales in the western United States are sources of selenium that can be loaded into the aquatic environment through mining, agricultural, and energy production processes. The mobilization of selenium from shales through agricultural irrigation has been recognized since the 1930s; however, discovery of deformities in birds and other wildlife using agricultural habi
Authors
Michael R. Rosen, Susan E.W. De La Cruz, Krishangi D. Groover, Isa Woo, Sarah A. Roberts, Melanie J. Davis, Cristiana Y. Antonino
Natural and anthropogenic hexavalent chromium, Cr(VI), in groundwater near a mapped plume, Hinkley, California
The Pacific Gas and Electric Company (PG&E) Hinkley compressor station, in the Mojave Desert, 80 miles northeast of Los Angeles, California, is used to compress natural gas as it is transported through a pipeline from Texas to California. Between 1952 and 1964, cooling water was treated with a compound containing hexavalent chromium, Cr(VI), to prevent corrosion of machinery within the compressor
Authors
John A. Izbicki, Krishangi D. Groover, Whitney A. Seymour, David M. Miller, John G. Warden, Laurence G. Miller
Predevelopment water levels, groundwater recharge, and selected hydrologic properties of aquifer materials, Hinkley and Water Valleys, California
Hydrologic and geophysical data were collected to support updates to an existing groundwater-flow model of Hinkley Valley, California, in the Mojave Desert about 80 miles northeast of Los Angeles, California. These data provide information on predevelopment (pre-1930) water levels, groundwater recharge, and selected hydrologic properties of aquifer materials.A predevelopment groundwater-level map,
Authors
Krishangi D. Groover, John A. Izbicki, Whitney A. Seymour, Anthony A. Brown, Randall E. Bayless, Carole D. Johnson, Katherine L. Pappas, Gregory A. Smith, Dennis A. Clark, Joshua Larsen, Meghan C. Dick, Lorraine E. Flint, Christina L. Stamos, John G. Warden
Introduction to study area hydrogeology, chromium sources, site history, and purpose of study
Between 1952 and 1964, hexavalent chromium, Cr(VI), was released into groundwater from the Pacific Gas and Electric Company (PG&E) Hinkley compressor station in the Mojave Desert 80 miles (mi) northeast of Los Angeles, California. Remediation began in 1992, and in 2010, site cleanup was projected to require between 10 and 95 years and was expected to cost between $36 and $176 million. A 2007 PG&E
Authors
John A. Izbicki, Krishangi D. Groover, David M. Miller, Whitney A. Seymour, John G. Warden, Laurence G. Miller
Survey of chromium and selected element concentrations in rock, alluvium, and core material
Between 1952 and 1964, hexavalent chromium, Cr(VI), was released into groundwater from the Pacific Gas and Electric Company (PG&E) compressor station in Hinkley, California, in the western Mojave Desert 80 miles northeast of Los Angeles, California. In 2015, the extent of anthropogenic Cr(VI) in groundwater in Hinkley and Water Valleys was uncertain, and some Cr(VI) in groundwater may be naturally
Authors
John A. Izbicki, Krishangi D. Groover
Chromium in minerals and selected aquifer materials
Between 1952 and 1964, hexavalent chromium, Cr(VI), was released into groundwater from a Pacific Gas and Electric Company (PG&E) compressor station in Hinkley, California, in the western Mojave Desert 80 miles northeast of Los Angeles, California. In 2015, the extent of anthropogenic Cr(VI) in groundwater in Hinkley and Water Valleys was uncertain, but some Cr(VI) in groundwater may be naturally o
Authors
Krishangi D. Groover, John A. Izbicki, William Benzel, Jean Morrison, Andrea L. Foster
Evaluation of natural and anthropogenic (human-made) hexavalent chromium
Hexavalent chromium, Cr(VI), was released between 1952 and 1964 from the Pacific Gas and Electric Company (PG&E) Hinkley compressor station, in the Mojave Desert about 80 miles northeast of Los Angeles, California. Geologic, geochemical, and hydrologic data from more than 100 wells collected between March 2015 and November 2017 were interpreted using a summative-scale analysis to define the extent
Authors
John A. Izbicki, John G. Warden, Krishangi D. Groover, Whitney A. Seymour
Sequestration and reoxidation of chromium in experimental microcosms
Groundwater containing hexavalent chromium, Cr(VI), downgradient from the Pacific Gas and Electric Company (PG&E) Hinkley compressor station in the Mojave Desert, 80 miles northeast of Los Angeles, California, is undergoing bioremediation using added ethanol as a reductant in a volume of the aquifer defined as the in situ reactive zone (IRZ). This treatment reduces Cr(VI) to trivalent chromium, Cr
Authors
Laurence G. Miller, Callum E. Bobb, Andrea L. Foster, Emily G. Wright, Stacy C. Bennett, Krishangi D. Groover, John A. Izbicki
Summary and conclusions
Executive SummaryChromium concentrations in rock and aquifer material in Hinkley and Water Valleys in the Mojave Desert, 80 miles northeast of Los Angeles, California, are generally low compared to the average chromium concentration of 185 milligrams per kilogram (mg/kg) in the average bulk continental crust. Chromium concentrations in felsic, coarse-textured “Mojave-type” deposits, composed of Mo
Authors
John A. Izbicki, Krishangi D. Groover, Whitney A. Seymour, David M. Miller, John G. Warden, Laurence G. Miller