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Regional Groundwater Monitoring

As required by SB 4 (Pavley, 2013) and detailed in the Model Criteria for Groundwater Monitoring in areas of Oil and Gas Well Stimulation (Model Criteria), State Water Board is to implement a Regional Monitoring Program in order to protect all waters designated for any beneficial use, while prioritizing the monitoring of groundwater that is or has the potential to be a source of drinking water.

Factors considered for the Regional Monitoring Program include well stimulation treatments, among other oil and gas activities that have the potential to contaminate groundwater, such as an oil and gas well failure or breach. Fluids produced or introduced in the well stimulation process including, but not limited to, produced water ponds and Underground Injection Control (UIC) wells are also examined in the Regional Monitoring Program. The United States Geological Survey (USGS) is the technical lead for the Regional Monitoring Program. A letter between the USGS and State Water Resources, dated January 22, 2018 details USGS objectives, sample collection and analysis protocols, quality- assurance procedures, approaches, and reporting procedures used for the Regional Monitoring Program.

  More information on the Regional Monitoring Program can be found on the USGS's California Oil, Gas, and Groundwater Monitoring Program website.

  Regional Monitoring Program Resources


Journal Articles

Tyne et al., 2021 “Investigating the effect of enhanced oil recovery on the noble gas signature of casing gases and produced waters from selected California oil fields

Stephens et al., 2021 “Stratigraphic and structural controls on groundwater salinity variations in the Poso Creek Oil Field, Kern County, California, USA

Karolyte et al., 2022 “Noble gas signatures constrain oil-field water as the carrier phase of hydrocarbons occurring in shallow aquifers in the San Joaquin Basin, USA”

McMahon et al., 2021“Relative risk of groundwater-quality degradation near California (USA) oil fields estimated from 3H, 14C, and 4He

Rosecrans et al., 2021 “Groundwater Quality of Aquifers Overlying the Oxnard Oil Field, Ventura County, California

Ball et al., 2020. “Probabilistic categorical groundwater salinity mapping from airborne electromagnetic data adjacent to California's Lost Hills and Belridge oil fields

Gillespie et al., 2019. “Groundwater salinity and the effects of produced water disposal in the Lost Hills–Belridge oil fields, Kern County, California

McMahon et al., 2019. “Occurrence and Sources of Radium in Groundwater Associated with Oil Fields in the Southern San Joaquin Valley, California

Wright et al., 2019. “Groundwater quality of a public supply aquifer in proximity to oil development, Fruitvale oil field, Bakersfield, California

McMahon et al., 2018. “Regional patterns in the geochemistry of oil-field water, southern San Joaquin Valley, California, USA

Stephens et al., 2019. “Groundwater salinity mapping using geophysical log analysis within the Fruitvale and Rosedale Ranch oil fields, Kern County, California, USA

Barry et al., 2018. “Tracing enhanced oil recovery signatures in casing gases from the Lost Hills oil field using noble gases.” The full article is available upon request from USGS via Matt Landon at landon@usgs.gov.

Kulongoski et al., 2018. “Origin of methane and sources of high concentrations in Los Angeles Groundwater” The full article is available upon request from USGS via Matt Landon at landon@usgs.gov.

Data Releases

Stephens et al., 2021 “Geochemical, geological, and geophysical data for wells in the Poso Creek Oil Field area, Kern County, California (ver. 2.0, September 2021)

Stephens et al., 2021 “Geochemical, geological, and geophysical data for wells in the Poso Creek Oil Field area, Kern County, California (ver. 2.0, September 2021)

Metzger et al., 2021, “Historical groundwater and produced water chemistry data compiled for the San Ardo Oil Field and vicinity, Monterey County, central California

Rosecrans, et al., 2021, “Water chemistry data for samples collected at groundwater sites near the Oxnard oil field, June 2017–August 2017, Ventura County, California

Stephens, et al., 2021, “Mud logs from the Oxnard Oil Field, Ventura County, California

Stephens, et al., 2021, “Fluid levels in the Oxnard Oil Field, Ventura County, California

Everett et al., 2020. “Aquifer test data for the Belridge multiple-well monitoring site (BWSD), Kern County, California
Metzger et al., 2020. "Inorganic chemistry data for groundwater wells near selected oil fields in the southwestern San Joaquin Valley, central California”
Metzger et al., 2020. “Historical produced water chemistry data compiled for selected oil fields in Los Angeles and Orange Counties, southern California
Metzger and Herrera, 2020. “Historical produced water chemistry data compiled for the Orcutt and Oxnard oil fields, Santa Babara and Ventura Counties, southern California
Ball and Davis, 2020. “Supporting groundwater salinity data used for salinity mapping adjacent to the Lost Hills and Belridge Oil Fields, Kern County, California
Ball, L.B. 2020. “Airborne electromagnetic and magnetic survey data, San Joaquin Valley near Lost Hills, California, October 2016” (02/24/2020)
Everett et al., 2020. “Aquifer test data for multiple-well monitoring site (LHSP), Kern County, California
Oxnard and Orcutt groundwater quality data collected by the RMP (12/18/2019)

Gans et al., 2019. "Historical Produced Water Chemistry Data Complied for the Elk Hills Oilfield, Kern County, California" 

Gillepsie et al., 2019. “Geological, geochemical, and geophysical data from the Lost Hills and Belridge oil fields: U.S. Geological Survey data release

Everett et al., 2019. “Geochemical and geophysical data for selected wells in and surrounding the South Cuyama oil and gas field

Gans et al., 2019. “Historical produced water chemistry data compiled for the Lost Hills and North and South Belridge Oilfields, Kern County, California

Haugen et al., 2018. "Geophysical and geochemical data for salinity mapping in the Midway-Sunset oil field area"

Stephens et al., 2018“Geochemical, geological, and geophysical data for wells in the Poso Creek oil and gas field, Kern County, California

McCarlson et al., 2018. "Water chemistry data for samples collected at groundwater sites near the Fruitvale oil field, September 2016–February 2017, Kern County, California"

Stephens et al., 2018“Geochemical and geophysical data for wells in the Fruitvale and Rosedale Ranch oil and gas fields, Kern County, California, USA

Davis et al., 2018. "Groundwater and surface water chemistry results for samples collected near the Lost Hills and North and South Belridge oil fields, Kern County, California"

Metzger et al., 2018. "Water and petroleum well data used for preliminary regional groundwater salinity mapping near selected oil fields in central and southern California"

Davis et al., 2018. “Data Analyzed for the Preliminary Prioritization of California Oil and Gas Fields for Regional Groundwater Monitoring”

Gannon et al., 2018 “Produced water chemistry data for the Lost Hills, Fruitvale, and North and South Belridge study areas, Southern San Joaquin Valley, California

Gans et al., 2018. “Historical produced water chemistry data compiled for the Fruitvale Oilfield, Kern County, California”

Kulongoski et al., 2016. “Produced water chemistry data for samples from four petroleum wells, Southern San Joaquin Valley, California 2014


USGS oil and gas regional monitoring activities are presented at our public stakeholder meetings. Recordings of recent meetings are below:

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   Regional Monitoring Program Mapping Tool

Visit the Regional Groundwater Monitoring Program online map to spatially view study areas and access available publications for each study area.

Thumbnail of Oil and Gas Program Study Area Publications Web Application