Tracy Davis (Former Employee)
Science and Products
Groundwater elevation data and models in and around select California oil fields (ver. 2.0, May 2024)
This data release contains groundwater elevation data and the associated model/code used to create groundwater elevation surfaces in and around select oil fields in California. The data and model provided here are intended to supplement interpretative manuscripts. Specific study areas will be added as Child Items found in this data release. Groundwater elevations are usually collected from individ
Water chemistry data for samples collected at groundwater sites near the Orcutt Oil Field, September 2017?March 2018, Santa Barbara County, California
In cooperation with the California State Water Resources Control Board Oil and Gas Regional Groundwater Monitoring Program the U.S. Geological Survey collected and analyzed groundwater and associated quality control (QC) samples to assess regional groundwater quality overlying and adjacent to the Orcutt Oil Field during September 2017 through March 2018. Groundwater samples were collected from 15
Produced water disposal at percolation and evaporation ponds in and near oil fields in the southwestern San Joaquin Valley, California (ver. 2.0, October 2024)
The U.S. Geological Survey (USGS) in cooperation with the California State Water Resources Control Board compiled and analyzed data on water production and produced water disposal on land at oil and gas fields in the southwestern San Joaquin Vallley, Kern County, California. Data were compiled from information in state and local agencies’ databases and cover a period of record ranging from the ear
Water chemistry data for samples collected at groundwater sites in the Montebello Oil Field study area, September 2014–October 2018, Los Angeles County, California
The California State Water Resources Control Board (State Water Board) initiated the Regional Groundwater Monitoring Program (RMP) to assess effects of oil and gas development on groundwater designated for any beneficial use. The U.S. Geological Survey (USGS) is the technical lead in conducting the RMP through the California Oil, Gas, and Groundwater (COGG) Program, working in cooperation with the
Geological, geochemical, and geophysical data from the Lost Hills and Belridge oil fields
The U.S. Geological Survey (USGS) in cooperation with the California State Water Resources Control Board compiled and analyzed data for mapping groundwater salinity and characterizing aquifer systems in and near selected oil and gas fields in California. Data for the Lost Hills, North Belridge, and South Belridge oil fields include production and injection volumes, oil show data, formation pressur
Supporting groundwater salinity data used for salinity mapping adjacent to the Lost Hills and Belridge oil fields, Kern County, California
This dataset contains summarized historical groundwater salinity observations from wells near the Lost Hills and Belridge oil fields in the southwestern San Joaquin Valley, Kern County, California. Total dissolved solids (TDS) concentration, electrical fluid conductivity (EC), and well construction information were aggregated from public data sources and local water management agencies. Trends in
Water chemistry data for samples collected at groundwater sites near the Oxnard oil field, June 2017-August 2017, Ventura County, California
In cooperation with the California State Water Resources Control Board's oil and gas Regional Monitoring Program, the U.S. Geological Survey collected and analyzed groundwater and associated quality control (QC) samples during June 2017 - August 2017. Groundwater samples were collected from one public supply well, four monitoring wells, and nine irrigation wells located within a three- mile buffer
Water chemistry data for samples collected at groundwater and surface-water sites near the Lost Hills and Belridge oil fields, November 2016-September 2017, Kern County, California
An investigation was done by the U.S. Geological Survey, in cooperation with the California State Water Resources Control Board's Program of Regional Groundwater Monitoring of Water Quality in Areas of Oil and Gas Production, to assess the effects of oil and gas production activities on nearby groundwater resources. During November 2016 September 2017, 30 samples were collected at groundwater well
Data analyzed for the preliminary prioritization of California oil and gas fields for regional groundwater monitoring
There are 487 onshore oil and gas fields in California encompassing 3,392 square miles of aggregated area. The California State Water Resources Control Board (State Water Board) initiated a Regional Monitoring Program (RMP) in July 2015, intended to determine where and to what degree groundwater quality may be at potential risk to contamination related to oil and gas development activities includi
Water and petroleum well data used for preliminary regional groundwater salinity mapping near selected oil fields in central and southern California
This digital data set contains total dissolved solids (either reported or calculated from specific conductance in lieu of reported total dissolved solids data), well construction, and well identifying information for 1,131 petroleum wells and 3,546 water wells used to map salinity in and around 31 southern and central California oil fields. The data set also includes ancillary data in the form of
Water chemistry data for samples collected at groundwater sites near the Fruitvale oil field, September 2016-February 2017, Kern County, California
As part of the California State Water Resources Control Board's Regional Groundwater Monitoring Program of Water Quality in Areas of Oil and Gas Production, during September 2016-February 2017, the U.S. Geological Survey collected and analyzed groundwater and associated quality-control (QC) samples from 14 water-production wells located within a three mile buffer zone of and in the Fruitvale Oil f
Produced water chemistry for samples from four petroleum wells, southern San Joaquin Valley, California, 2014
The U.S. Geological Survey (USGS) in cooperation with the California State Water Resources Control Board collected produced water samples from four petroleum wells in the southern San Joaquin Valley on November 5, 2014. This digital dataset contains the site information, analyzing laboratories and methods, and water chemistry and quality control results for these samples. Water chemistry results i
Filter Total Items: 21
Assessing potential effects of oil and gas development activities on groundwater quality near and overlying the Elk Hills and North Coles Levee Oil Fields, San Joaquin Valley, California
Groundwater resources are utilized near areas of intensive oil and gas development in California’s San Joaquin Valley. In this study, we examined chemical and isotopic data to assess if thermogenic gas or saline water from oil producing formations have mixed with groundwater near the Elk Hills and North Coles Levee Oil Fields in the southwestern San Joaquin Valley. Major ion concentrations and sta
Authors
John G. Warden, Matthew K. Landon, Michael J. Stephens, Tracy Davis, Janice M. Gillespie, Peter B. McMahon, Justin T. Kulongoski, Andrew G. Hunt, David H. Shimabukuro, Riley Gannon, Lyndsay B. Ball
Fluid migration pathways to groundwater in mature oil fields: Exploring the roles of water injection/production and oil-well integrity in California, USA
Mature oil fields potentially contain multiple fluid migration pathways toward protected groundwater (total dissolved solids, TDS, in nonexempted aquifer <10,000 mg/L) because of their extensive development histories. Time-series data for water use, fluid pressures, oil-well construction, and geochemistry from the South Belridge and Lost Hills mature oil fields in California are used to explore th
Authors
Peter B. McMahon, Matthew K. Landon, Michael J. Stephens, Kimberly A. Taylor, Janice M. Gillespie, Tracy Davis, David H. Shimabukuro
Groundwater quality near the Montebello Oil Field, Los Angeles County, California
Groundwater quality and potential sources and migration pathways of chemical constituents associated with hydrocarbon-bearing formations were assessed by the U.S. Geological Survey for the California State Water Resources Control Board Oil and Gas Regional Monitoring Program (RMP). Groundwater samples were collected as part of the RMP from 21 preexisting wells used for public supply, monitoring, o
Authors
Jennifer S. Stanton, Michael Land, Matthew K. Landon, David H. Shimabukuro, Peter B. McMahon, Tracy A. Davis, Andrew G. Hunt, Theron A. Sowers
Occurrence of water and thermogenic gas from oil-bearing formations in groundwater near the Orcutt Oil Field, California, USA
Study regionSanta Barbara County, California, USA.Study focusTo analyze a wide array of newly collected chemical, isotopic, dissolved gas, and age dating tracers in conjunction with historical data from groundwater and oil wells to determine if water and/or thermogenic gas from oil-bearing formations have mixed with groundwater in the Orcutt Oil Field and surrounding area.New hydrological insights
Authors
Robert Anders, Matthew K. Landon, Peter B. McMahon, Justin T. Kulongoski, Andrew G. Hunt, Tracy Davis
Noble gas signatures constrain oil-field water as the carrier phase of hydrocarbons occurring in shallow aquifers in the San Joaquin Basin, USA
Noble gases record fluid interactions in multiphase subsurface environments through fractionation processes during fluid equilibration. Water in the presence of hydrocarbons at the subsurface acquires a distinct elemental signature due to the difference in solubility between these two fluids. We find the atmospheric noble gas signature in produced water is partially preserved after hydrocarbons pr
Authors
Ruta Karolyte, Peter H. Barry, Andrew G. Hunt, Justin T. Kulongoski, R. L. Tyne, Tracy Davis, Michael Wright, Peter B. McMahon, C. J. Ballentine
Relative risk of groundwater-quality degradation near California (USA) oil fields estimated from 3H, 14C, and 4He
Relative risks of groundwater-quality degradation near selected California oil fields are estimated by examining spatial and temporal patterns in chemical and isotopic data in the context of groundwater-age categories defined by tritium and carbon-14. In the Coastal basins, western San Joaquin Valley (SJV), and eastern SJV; 82, 76, and 0% of samples are premodern (pre-1953 recharge), respectively;
Authors
Peter B. McMahon, Matthew K. Landon, Tracy Davis, Michael Wright, Celia Z. Rosecrans, Robert Anders, Michael Land, Justin T. Kulongoski, Andrew G. Hunt
Groundwater quality of aquifers overlying the Oxnard Oil Field, Ventura County, California
Groundwater samples collected from irrigation, monitoring, and municipal supply wells near the Oxnard Oil Field were analyzed for chemical and isotopic tracers to evaluate if thermogenic gas or water from hydrocarbon-bearing formations have mixed with surrounding groundwater. New and historical data show no evidence of water from hydrocarbon-bearing formations in groundwater overlying the field. H
Authors
Celia Z. Rosecrans, Matthew K. Landon, Katherine Marie Ransom, Janice M. Gillespie, Justin T. Kulongoski, Michael J. Stephens, Andrew G. Hunt, David H. Shimabukuro, Tracy Davis
Probabilistic categorical groundwater salinity mapping from airborne electromagnetic data adjacent to California’s Lost Hills and Belridge oil fields
Growing water stress has led to emerging interest in protecting fresh and brackish groundwater as a potential supplement to water supplies and raised questions about factors that could affect the future quality of fresh and brackish aquifers. Limited well infrastructure, particularly in regions where elevated salinity has led to limited historical groundwater development, hinders traditional mappi
Authors
Lyndsay B. Ball, Tracy Davis, Burke J. Minsley, Janice M. Gillespie, Matthew K. Landon
Groundwater salinity and the effects of produced water disposal in the Lost Hills-Belridge oilfields, Kern County, California
Increased oil and gas production in many areas has led to concerns over the effects these activities may be having on nearby groundwater quality. In this study we determine the lateral and vertical extent of groundwater with less than 10,000 milligrams per liter (mg/l) total dissolved solids (TDS) near the Lost Hills-Belridge oilfields in northwestern Kern County, California and document evidence
Authors
Janice M. Gillespie, Tracy Davis, Michael J. Stephens, Lyndsay B. Ball, Matthew K. Landon
Occurrence and sources of radium in groundwater associated with oil fields in the southern San Joaquin Valley, California
Geochemical data from 40 water wells were used to examine the occurrence and sources of radium (Ra) in groundwater associated with three oil fields in California (Fruitvale, Lost Hills, South Belridge). 226Ra+228Ra activities (range=0.010-0.51 Bq/L) exceeded the 0.185 Bq/L drinking-water standard in 18% of the wells (not drinking-water wells). Radium activities were correlated with TDS concentrati
Authors
Peter B. McMahon, Avner Vengosh, Tracy Davis, Matthew K. Landon, Rebecca L. Tyne, Michael Wright, Justin T. Kulongoski, Andrew G. Hunt, Peter H. Barry, A.J. Kondash, Z. Wang, Christopher J. Ballentine
Regional patterns in the geochemistry of oil-field water, southern San Joaquin Valley, California, USA
Chemical and isotopic data for water co-extracted with hydrocarbons in oil and gas fields are commonly used to examine the source of the formation water and possible impacts on groundwater in areas of oil and gas development. Understanding the geochemical variability of oil-field water could help to evaluate its origin and delineate possible contamination of shallow aquifers in cases where oil-fie
Authors
Peter B. McMahon, Justin T. Kulongoski, Avner Vengosh, Isabelle M. Cozzarelli, Matthew K. Landon, Yousif K. Kharaka, Janice M. Gillespie, Tracy Davis
Prioritization of oil and gas fields for regional groundwater monitoring based on a preliminary assessment of petroleum resource development and proximity to California’s groundwater resources
The California State Water Resources Control Board initiated a regional monitoring program in July 2015 to determine where and to what degree groundwater quality may be adversely impacted by oil and gas development activities. A key issue in the implementation of the regional groundwater monitoring program is that each year, detailed characterization work can be done in only a few of California’s
Authors
Tracy Davis, Matthew K. Landon, George L. Bennett
Science and Products
Groundwater elevation data and models in and around select California oil fields (ver. 2.0, May 2024)
This data release contains groundwater elevation data and the associated model/code used to create groundwater elevation surfaces in and around select oil fields in California. The data and model provided here are intended to supplement interpretative manuscripts. Specific study areas will be added as Child Items found in this data release. Groundwater elevations are usually collected from individ
Water chemistry data for samples collected at groundwater sites near the Orcutt Oil Field, September 2017?March 2018, Santa Barbara County, California
In cooperation with the California State Water Resources Control Board Oil and Gas Regional Groundwater Monitoring Program the U.S. Geological Survey collected and analyzed groundwater and associated quality control (QC) samples to assess regional groundwater quality overlying and adjacent to the Orcutt Oil Field during September 2017 through March 2018. Groundwater samples were collected from 15
Produced water disposal at percolation and evaporation ponds in and near oil fields in the southwestern San Joaquin Valley, California (ver. 2.0, October 2024)
The U.S. Geological Survey (USGS) in cooperation with the California State Water Resources Control Board compiled and analyzed data on water production and produced water disposal on land at oil and gas fields in the southwestern San Joaquin Vallley, Kern County, California. Data were compiled from information in state and local agencies’ databases and cover a period of record ranging from the ear
Water chemistry data for samples collected at groundwater sites in the Montebello Oil Field study area, September 2014–October 2018, Los Angeles County, California
The California State Water Resources Control Board (State Water Board) initiated the Regional Groundwater Monitoring Program (RMP) to assess effects of oil and gas development on groundwater designated for any beneficial use. The U.S. Geological Survey (USGS) is the technical lead in conducting the RMP through the California Oil, Gas, and Groundwater (COGG) Program, working in cooperation with the
Geological, geochemical, and geophysical data from the Lost Hills and Belridge oil fields
The U.S. Geological Survey (USGS) in cooperation with the California State Water Resources Control Board compiled and analyzed data for mapping groundwater salinity and characterizing aquifer systems in and near selected oil and gas fields in California. Data for the Lost Hills, North Belridge, and South Belridge oil fields include production and injection volumes, oil show data, formation pressur
Supporting groundwater salinity data used for salinity mapping adjacent to the Lost Hills and Belridge oil fields, Kern County, California
This dataset contains summarized historical groundwater salinity observations from wells near the Lost Hills and Belridge oil fields in the southwestern San Joaquin Valley, Kern County, California. Total dissolved solids (TDS) concentration, electrical fluid conductivity (EC), and well construction information were aggregated from public data sources and local water management agencies. Trends in
Water chemistry data for samples collected at groundwater sites near the Oxnard oil field, June 2017-August 2017, Ventura County, California
In cooperation with the California State Water Resources Control Board's oil and gas Regional Monitoring Program, the U.S. Geological Survey collected and analyzed groundwater and associated quality control (QC) samples during June 2017 - August 2017. Groundwater samples were collected from one public supply well, four monitoring wells, and nine irrigation wells located within a three- mile buffer
Water chemistry data for samples collected at groundwater and surface-water sites near the Lost Hills and Belridge oil fields, November 2016-September 2017, Kern County, California
An investigation was done by the U.S. Geological Survey, in cooperation with the California State Water Resources Control Board's Program of Regional Groundwater Monitoring of Water Quality in Areas of Oil and Gas Production, to assess the effects of oil and gas production activities on nearby groundwater resources. During November 2016 September 2017, 30 samples were collected at groundwater well
Data analyzed for the preliminary prioritization of California oil and gas fields for regional groundwater monitoring
There are 487 onshore oil and gas fields in California encompassing 3,392 square miles of aggregated area. The California State Water Resources Control Board (State Water Board) initiated a Regional Monitoring Program (RMP) in July 2015, intended to determine where and to what degree groundwater quality may be at potential risk to contamination related to oil and gas development activities includi
Water and petroleum well data used for preliminary regional groundwater salinity mapping near selected oil fields in central and southern California
This digital data set contains total dissolved solids (either reported or calculated from specific conductance in lieu of reported total dissolved solids data), well construction, and well identifying information for 1,131 petroleum wells and 3,546 water wells used to map salinity in and around 31 southern and central California oil fields. The data set also includes ancillary data in the form of
Water chemistry data for samples collected at groundwater sites near the Fruitvale oil field, September 2016-February 2017, Kern County, California
As part of the California State Water Resources Control Board's Regional Groundwater Monitoring Program of Water Quality in Areas of Oil and Gas Production, during September 2016-February 2017, the U.S. Geological Survey collected and analyzed groundwater and associated quality-control (QC) samples from 14 water-production wells located within a three mile buffer zone of and in the Fruitvale Oil f
Produced water chemistry for samples from four petroleum wells, southern San Joaquin Valley, California, 2014
The U.S. Geological Survey (USGS) in cooperation with the California State Water Resources Control Board collected produced water samples from four petroleum wells in the southern San Joaquin Valley on November 5, 2014. This digital dataset contains the site information, analyzing laboratories and methods, and water chemistry and quality control results for these samples. Water chemistry results i
Filter Total Items: 21
Assessing potential effects of oil and gas development activities on groundwater quality near and overlying the Elk Hills and North Coles Levee Oil Fields, San Joaquin Valley, California
Groundwater resources are utilized near areas of intensive oil and gas development in California’s San Joaquin Valley. In this study, we examined chemical and isotopic data to assess if thermogenic gas or saline water from oil producing formations have mixed with groundwater near the Elk Hills and North Coles Levee Oil Fields in the southwestern San Joaquin Valley. Major ion concentrations and sta
Authors
John G. Warden, Matthew K. Landon, Michael J. Stephens, Tracy Davis, Janice M. Gillespie, Peter B. McMahon, Justin T. Kulongoski, Andrew G. Hunt, David H. Shimabukuro, Riley Gannon, Lyndsay B. Ball
Fluid migration pathways to groundwater in mature oil fields: Exploring the roles of water injection/production and oil-well integrity in California, USA
Mature oil fields potentially contain multiple fluid migration pathways toward protected groundwater (total dissolved solids, TDS, in nonexempted aquifer <10,000 mg/L) because of their extensive development histories. Time-series data for water use, fluid pressures, oil-well construction, and geochemistry from the South Belridge and Lost Hills mature oil fields in California are used to explore th
Authors
Peter B. McMahon, Matthew K. Landon, Michael J. Stephens, Kimberly A. Taylor, Janice M. Gillespie, Tracy Davis, David H. Shimabukuro
Groundwater quality near the Montebello Oil Field, Los Angeles County, California
Groundwater quality and potential sources and migration pathways of chemical constituents associated with hydrocarbon-bearing formations were assessed by the U.S. Geological Survey for the California State Water Resources Control Board Oil and Gas Regional Monitoring Program (RMP). Groundwater samples were collected as part of the RMP from 21 preexisting wells used for public supply, monitoring, o
Authors
Jennifer S. Stanton, Michael Land, Matthew K. Landon, David H. Shimabukuro, Peter B. McMahon, Tracy A. Davis, Andrew G. Hunt, Theron A. Sowers
Occurrence of water and thermogenic gas from oil-bearing formations in groundwater near the Orcutt Oil Field, California, USA
Study regionSanta Barbara County, California, USA.Study focusTo analyze a wide array of newly collected chemical, isotopic, dissolved gas, and age dating tracers in conjunction with historical data from groundwater and oil wells to determine if water and/or thermogenic gas from oil-bearing formations have mixed with groundwater in the Orcutt Oil Field and surrounding area.New hydrological insights
Authors
Robert Anders, Matthew K. Landon, Peter B. McMahon, Justin T. Kulongoski, Andrew G. Hunt, Tracy Davis
Noble gas signatures constrain oil-field water as the carrier phase of hydrocarbons occurring in shallow aquifers in the San Joaquin Basin, USA
Noble gases record fluid interactions in multiphase subsurface environments through fractionation processes during fluid equilibration. Water in the presence of hydrocarbons at the subsurface acquires a distinct elemental signature due to the difference in solubility between these two fluids. We find the atmospheric noble gas signature in produced water is partially preserved after hydrocarbons pr
Authors
Ruta Karolyte, Peter H. Barry, Andrew G. Hunt, Justin T. Kulongoski, R. L. Tyne, Tracy Davis, Michael Wright, Peter B. McMahon, C. J. Ballentine
Relative risk of groundwater-quality degradation near California (USA) oil fields estimated from 3H, 14C, and 4He
Relative risks of groundwater-quality degradation near selected California oil fields are estimated by examining spatial and temporal patterns in chemical and isotopic data in the context of groundwater-age categories defined by tritium and carbon-14. In the Coastal basins, western San Joaquin Valley (SJV), and eastern SJV; 82, 76, and 0% of samples are premodern (pre-1953 recharge), respectively;
Authors
Peter B. McMahon, Matthew K. Landon, Tracy Davis, Michael Wright, Celia Z. Rosecrans, Robert Anders, Michael Land, Justin T. Kulongoski, Andrew G. Hunt
Groundwater quality of aquifers overlying the Oxnard Oil Field, Ventura County, California
Groundwater samples collected from irrigation, monitoring, and municipal supply wells near the Oxnard Oil Field were analyzed for chemical and isotopic tracers to evaluate if thermogenic gas or water from hydrocarbon-bearing formations have mixed with surrounding groundwater. New and historical data show no evidence of water from hydrocarbon-bearing formations in groundwater overlying the field. H
Authors
Celia Z. Rosecrans, Matthew K. Landon, Katherine Marie Ransom, Janice M. Gillespie, Justin T. Kulongoski, Michael J. Stephens, Andrew G. Hunt, David H. Shimabukuro, Tracy Davis
Probabilistic categorical groundwater salinity mapping from airborne electromagnetic data adjacent to California’s Lost Hills and Belridge oil fields
Growing water stress has led to emerging interest in protecting fresh and brackish groundwater as a potential supplement to water supplies and raised questions about factors that could affect the future quality of fresh and brackish aquifers. Limited well infrastructure, particularly in regions where elevated salinity has led to limited historical groundwater development, hinders traditional mappi
Authors
Lyndsay B. Ball, Tracy Davis, Burke J. Minsley, Janice M. Gillespie, Matthew K. Landon
Groundwater salinity and the effects of produced water disposal in the Lost Hills-Belridge oilfields, Kern County, California
Increased oil and gas production in many areas has led to concerns over the effects these activities may be having on nearby groundwater quality. In this study we determine the lateral and vertical extent of groundwater with less than 10,000 milligrams per liter (mg/l) total dissolved solids (TDS) near the Lost Hills-Belridge oilfields in northwestern Kern County, California and document evidence
Authors
Janice M. Gillespie, Tracy Davis, Michael J. Stephens, Lyndsay B. Ball, Matthew K. Landon
Occurrence and sources of radium in groundwater associated with oil fields in the southern San Joaquin Valley, California
Geochemical data from 40 water wells were used to examine the occurrence and sources of radium (Ra) in groundwater associated with three oil fields in California (Fruitvale, Lost Hills, South Belridge). 226Ra+228Ra activities (range=0.010-0.51 Bq/L) exceeded the 0.185 Bq/L drinking-water standard in 18% of the wells (not drinking-water wells). Radium activities were correlated with TDS concentrati
Authors
Peter B. McMahon, Avner Vengosh, Tracy Davis, Matthew K. Landon, Rebecca L. Tyne, Michael Wright, Justin T. Kulongoski, Andrew G. Hunt, Peter H. Barry, A.J. Kondash, Z. Wang, Christopher J. Ballentine
Regional patterns in the geochemistry of oil-field water, southern San Joaquin Valley, California, USA
Chemical and isotopic data for water co-extracted with hydrocarbons in oil and gas fields are commonly used to examine the source of the formation water and possible impacts on groundwater in areas of oil and gas development. Understanding the geochemical variability of oil-field water could help to evaluate its origin and delineate possible contamination of shallow aquifers in cases where oil-fie
Authors
Peter B. McMahon, Justin T. Kulongoski, Avner Vengosh, Isabelle M. Cozzarelli, Matthew K. Landon, Yousif K. Kharaka, Janice M. Gillespie, Tracy Davis
Prioritization of oil and gas fields for regional groundwater monitoring based on a preliminary assessment of petroleum resource development and proximity to California’s groundwater resources
The California State Water Resources Control Board initiated a regional monitoring program in July 2015 to determine where and to what degree groundwater quality may be adversely impacted by oil and gas development activities. A key issue in the implementation of the regional groundwater monitoring program is that each year, detailed characterization work can be done in only a few of California’s
Authors
Tracy Davis, Matthew K. Landon, George L. Bennett