Sign In
Skip Navigation LinksHome > DOGGR > FAQS > Glossary of Terms

Oil, Gas & Geothermal - Glossary of Terms

 

This glossary is intended to provide basic defintions for terms and acronyms used on the WST Disclosure website.


Jump Links: A BCDEFGHIJKLMNOPQRSTUVWXYZ Top


Term
  

Acid Fracturing

Back to Top

 
 

A well stimulation treatment, that, in whole or in part, includes the pressurized injection of acid into an underground geologic formation in order to fracture the formation, thereby causing or enhancing the production of oil or gas from a well.

Acid Matrix Stimulation Treatment

Back to Top

 
 

An acid treatment conducted at pressures lower than the applied pressure necessary to fracture the underground geologic formation.

Additive

Back to Top

 
 

A substance or combination of substances added to a base fluid for purposes of preparing well stimulation treatment fluid, including, but not limited to, acid stimulation fluid and hydraulic fracturing fluid.  An additive may serve additional purposes beyond the transmission of hydraulic pressure to the geologic formation, including increasing/decreasing viscosity, reducing friction, limiting bacteria, pH control, and decreasing corrosion.  An additive may be of any phase and may include proppants.  Additives are often given proprietary trade names.

Additive Concentration (%)

Back to Top

 
 

Concentration, by percent, of each additive used during WST.

Additive Supplier

Back to Top

 
 

Supplier of the WST fluid additive.

Analyte

Back to Top

 
 

The chemical constituents detected during testing and analysis of base fluid water source and recovered fluid samples.  Analysis of these samples is required for WST disclosure to determine the composition of the water used during WST and the fluids recovered from a well after WST.

Analytical Laboratory

Back to Top

 
 

The firm selected by the operator to analyze base fluid water source and recovered fluid samples for the presence of chemical constituents.

Analytical Laboratory Reports

Back to Top

 
 

Reports prepared by the analytical laboratory to document the process the laboratory uses to analyze the water source and recovered fluids, and report the analytical results. This report is included with the operator’s disclosure form.

Analytical Method

Back to Top

 
 

The standardized analytical technique (approved by the U.S. Environmental Protection Agency [U.S. EPA]) used by the analytical laboratory to determine the concentration of the chemical compounds or elements detected during water source or recovered fluid sample analysis.

Analytical Procedure Name

Back to Top

 
 

The name the analytical laboratory uses to describe an analytical method.

API

Back to Top

 
 

American Petroleum Institute. Oil and gas industry standards organization responsible for creating the numbering scheme for oil and gas wells. The Professional Petroleum Data Management Association (PPDM Association) has been responsible for the API Number standard since 2010.

API Number

Back to Top

 
 

A unique 8-digit numeric identifier assigned to each oil and gas well in the United States.


Jump Links: A B CDEFGHIJKLMNOPQRSTUVWXYZ Top


Term
  

Base Fluid

Back to Top

 
 

The continuous phase fluid used in the makeup of a well stimulation treatment fluid. The continuous phase fluid may include, but is not limited to, water, and may be a liquid or a hydrocarbon or nonhydrocarbon gas.  A well stimulation treatment may use more than one base fluid.

Base Fluid Suitability

Back to Top

 
 

Designation of whether the base fluid is suitable for irrigation or domestic use.

Base Fluid Water Source

Back to Top

 
 

The water source used as a base fluid supply.

Base Fluid Water Source Sample

Back to Top

 
 

A sample the operator collects at the base fluid water source location.

Baseline/Meridian

Back to Top

 
 

The U.S. Public Land Survey System (U.S. PLSS) is the surveying method used to describe and subdivide land. The baseline runs east-west, and the meridian runs north-south. The baseline and meridian are referenced to a designated initial point, upon which all surveys in a defined area are based.

BBLS

Back to Top

 
 

Barrels. Oil industry unit of measure for oil volume: 1 barrel = 42 gallons.

Bottom of Horizon (TVD)

Back to Top

 
 

The actual vertical depth to the bottom of the rock layer (production horizon) from which hydrocarbons are produced.

 


Jump Links: AB C DEFGHIJKLMNOPQRSTUVWXYZ Top


Term
  

CAS Number

Back to Top

 
 

See: Chemical Abstract Service Number.

CCR

Back to Top

 
 

California Code of Regulations. Well stimulation treatment (WST) is regulated under CCR Title 14, Sections 1751 through 1789.

Chemical Abstracts Service Number

Back to Top

 
 

A unique identification number assigned by the Chemical Abstracts Service (CAS) for every chemical compound or mixture of chemical compounds described in scientific literature.

Chemical Constituent (Chemical Name)

Back to Top

 
 

Name of the chemical compounds contained within the WST fluid additives.

Chemical Constituent Concentration (% mass)

Back to Top

 
 

Concentration of each chemical constituent of the WST fluid. The total (or total of each stage) should sum to 100%.

Chemical ID if no CAS No.

Back to Top

 
 

A unique identification number selected by the operator if no CAS number exists for the chemical constituent.

Class II Injection Well

Back to Top

 
 

Class II wells are used for the injection of fluids brought to the surface in connection with oil or gas production, for enhanced recovery of oil or gas, or for storage of liquid hydrocarbons.  (See 40 C.F.R. § 144.6(b).)  The Class II well designation was established by the U.S. EPA for the purpose of regulating injection wells under the Safe Drinking Water Act of 1974.

Confidential Well

Back to Top

 
 

The designation given to a well in accordance with Public Resources Code (PRC) section 3234, that protects certain information regarding the well from public disclosure for a limited period of time.

 


Jump Links: ABC D EFGHIJKLMNOPQRSTUVWXYZ Top


Term
  

Directional Drilling

Back to Top

 
 

An oil or gas well drilling technique in which drilling tools are used to control the direction and inclination of a wellbore.

District Code

Back to Top

 
 

The numerical code used by the Division to identify the geographic management District where the well is located. The code for each district is as follows:

  • 01. Cypress
  • 02. Ventura
  • 03. Orcutt
  • 04. Bakersfield
  • 05. Coalinga
  • 06. Sacramento

Division

Back to Top

 
 

The Division of Oil, Gas and Geothermal Resources, sometimes referred to as DOGGR, which is the division in the Department of Conservation responsible for regulating the oil, gas, and geothermal industry.

DOGGR

Back to Top

 
 

Division of Oil, Gas and Geothermal Resources. A Division in the Department of Conservation responsible for regulating the oil, gas and geothermal industry.


Jump Links: ABCD E FGHIJKLMNOPQRSTUVWXYZ Top


Term
  

EPA

Back to Top

 
 

Environmental Protection Agency. A Federal agency whose mission is to protect human health and the environment.


Jump Links: ABCDE F GHIJKLMNOPQRSTUVWXYZ Top


Term
  

Field Name

Back to Top

 
 

The name given to the geographic extent of the underground accumulation of oil and gas.

Formation Name, Bottom of Horizon

Back to Top

 
 

The name of the geologic formation at the bottom of the oil and gas production zone (horizon).

Formation Name, Top of Horizon

Back to Top

 
 

The name of the geologic formation at the top of the oil and gas production zone (horizon).

Fracture Azimuth

Back to Top

 
 

Axial direction of modeled well stimulation induced fractures in degrees (e.g., 0 = true north, 90 = east, 180 = south, 270 = west).

Fracture Height

Back to Top

 
 

Extent, in feet, of modeled well stimulation induced fractures parallel to the orientation of the wellbore.

Fracture Length

Back to Top

 
 

Extent, in feet, of modeled well stimulation induced fractures perpendicular to the orientation of the wellbore.

Ft.

Back to Top

 
 

Feet. A linear unit of measurement equal to 12 inches.


Jump Links: ABCDEF G HIJKLMNOPQRSTUVWXYZ Top


Term
  

GeoTracker

Back to Top

 
 

The Water Boards’ data management system for managing sites that impact groundwater, especially those that require groundwater cleanup (Underground Storage Tanks [UST], Department of Defense, Site Cleanup Program) as well as permitted facilities such as operating USTs and land disposal sites: http://geotracker.waterboards.ca.gov

Groundwater Monitoring Plan (GWMP)

Back to Top

 
 

A document approved by the State Water Resources Control Board (SWRCB) that outlines the program to monitor the possible impact of WST to local groundwater where water quality is sufficient to be considered a resource for drinking water or agricultural use.


Jump Links: ABCDEFG H IJKLMNOPQRSTUVWXYZ Top


Term
  

Horizontal Well

Back to Top

 
 

A directionally drilled well that is drilled vertically then turns to become near parallel (horizontal) with the ground surface.

Hydraulic Fracturing

Back to Top

 
 

A well stimulation treatment that, in whole or in part, includes the pressurized injection of one or more base fluids mixed with physical and chemical additives into an underground geologic formation in order to fracture the formation, thereby causing or enhancing the production of oil or gas from a well.


Jump Links: ABCDEFGHIJK L MNOPQRSTUVWXYZ Top


Term
  

Laboratory

Back to Top

 
 

The name of the laboratory, displayed as an abbreviation, where fluid analysis was conducted. Information for all abbreviations is provided on the Analytical Laboratory Abbreviations list.

Latitude

Back to Top

 
 

A geographic coordinate that specifies the distance the well is located north or south of the equator. Measured in terms of the 360 degrees of a circle.

Lease Name

Back to Top

 
 

The name of the mineral rights lease associated with the well. In some cases, there is no lease name and this field will be blank.

Letter of Concurrence (LOC)

Back to Top

 
 

A document from the State Water Resources Control Board (SWRCB) agreeing with the operator's assertion that there is no groundwater resource in the vicinity of the wells undergoing WST.

Longitude

Back to Top

 
 

A geographic coordinate that specifies the distance the well east or west of the prime meridian in Greenwich, England. Measured in terms of the 360 degrees of a circle.


Jump Links: ABCDEFGHIJKL M NOPQRSTUVWXYZ Top


Term
  

MD

Back to Top

 
 

See: Measured Depth.

MDL

Back to Top

 
 

See: Method Detection Limit.

Measured Depth

Back to Top

 
 

Depth measured along the wellbore. As the wellbore may be at an angle from vertical this number may not match true vertical depth measurements.

Method Detection Limit

Back to Top

 
 

The minimum concentration of a substance that can be measured and reported with 99% confidence that the analyte concentration is greater than zero. The method detection limit is laboratory-specific and is established by the analytical laboratory for each analytical method and each piece of analytical equipment.

MG/L

Back to Top

 
 

Milligrams per Liter. Unit of measurement for water sample concentration, equal to one milligram of a substance dissolved in one liter of water.


Jump Links: ABCDEFGHIJKLM N OPQRSTUVWXYZ Top


Term
  

N/A

Back to Top

 
 

Not Applicable.

Nature of Recovered Fluid

Back to Top

 
 

The physical form of the recovered fluid, which is typically water-based.

ND

Back to Top

 
 

Not Detected. The analyzed compound or analyte was not detected in the sample at or above the reporting limit.


Jump Links: ABCDEFGHIJKLMN O PQRSTUVWXYZ Top


Term
  

Offshore

Back to Top

 
 

A well where the wellbore is completed below the seabed.

Onshore

Back to Top

 
 

A well where the wellbore is completed below lands that are not submerged under ocean waters or inland bays during mean high tide.

Operator

Back to Top

 
 

A person who, by virtue of ownership, or under the authority of a lease or any other agreement, has the right to drill, operate, maintain, or control a well or production facility.

 


Jump Links: ABCDEFGHIJKLMNO P QRSTUVWXYZ Top


Term
  

PPB

Back to Top

 
 

Parts per Billion. A unit of measurement of the chemical concentration determined by comparing the mass of each constituent with the total mass of the sample. (1/1,000,000,000).

PPM

Back to Top

 
 

Parts per Million. A unit of measurement of the chemical concentration determined by comparing the mass of each constituent with the total mass of the sample. (1/1,000,000).

PCI/L

Back to Top

 
 

Picocuries per Liter. A unit of measurement for levels of radioactive compounds or elements, such as radon gas.

PLSS

Back to Top

 
 

Public Land Survey System. The system used by the Federal Government to survey, subdivide and describe land.

PRC

Back to Top

 
 

Public Resource Code. The California PRC was codified in 1939 to consolidate and revise the laws relating to natural resources (e.g., mines and mining, oil and gas, forestry).

Produced Water

Back to Top

 
 

Water extracted from the ground during oil production processes. Produced water is often, but not always, highly saline (briny) and usually contains some hydrocarbons.

PQL

Back to Top

 
 

Practical Quantitation Limit. The lowest concentration that can be reliably measured with precision and accuracy for a specific laboratory analytical method.


Jump Links: ABCDEFGHIJKLMNOPQ R STUVWXYZ Top


Term
  

Radioactive Constituent

Back to Top

 
 

Name of the radioactive element or constituent detected in the recovered fluid. Radioactive elements may be naturally occurring in the rock formations.

Radiological Component or Tracer

Back to Top

 
 

A radioactive compound used to track the movement of WST fluid through the formation.

Radiological Recovery Method

Back to Top

 
 

The method used to recover the radiological component or tracer.

Range

Back to Top

 
 

Used in the U.S. PLSS, the range is a measure of distance east or west from a referenced principal meridian, in units of six miles.

RDL

Back to Top

 
 

See: Reported Detection Limit.

Recovered Fluid

Back to Top

 
 

The fluids recovered following WST, either from flowing to the wellhead under pressure, or produced from the well.

Recovered Fluid Disposal Method

Back to Top

 
 

Disposal method of fluids recovered from the well following WST. Recovered fluids are often injected into Class II injection wells.

Recovered Fluid Sample

Back to Top

 
 

A sample the operator collects of the fluids recovered following WST.

Reported Detection Limit

Back to Top

 
 

The lowest concentration at which an analyte can be detected in a sample, and its concentration reported, with a reasonable degree of accuracy and precision. This is a laboratory-specific number.

Result Qualifier

Back to Top

 
 

The code identifying the qualifier of an analytical result (e.g., greater than, equal, etc.).


Jump Links: ABCDEFGHIJKLMNOPQR S TUVWXYZ Top


Term
  

Sample ID

Back to Top

 
 

The name the well operator gives to the fluid sample.

SB 4

Back to Top

 
 

Senate Bill 4 for WST (2013) was enacted into law on January 1, 2014 under the PRC, Sections 3000 through 3161.

Section

Back to Top

 
 

Used in the U.S. PLSS, a section is approximately one-square-mile block of land. There are 36 sections in a survey township.

Slurry Volume

Back to Top

 
 

Volume in barrels of fluid, including base fluid, proppant, and additives used during WST.

Stage

Back to Top

 
 

A specific perforation interval in a WST that is isolated from other perforation intervals when undergoing a treatment process that is specific to that interval.

Stage Number

Back to Top

 
 

WST stage number as identified by the operator.

Stage Bottom (MD)

Back to Top

 
 

Depth, in feet, to the bottom of the perforated interval of each well stimulation stage, measured along the wellbore.

Stage Bottom (TVD)

Back to Top

 
 

True vertical depth, in feet, to the bottom of the perforated interval of each well stimulation stage.

Stage Top (MD)

Back to Top

 
 

Depth, in feet, to the top of the perforated interval of each well stimulation stage, measured along the wellbore.

Stage Top (TVD)

Back to Top

 
 

True vertical depth, in feet, to the top of the perforated interval of each well stimulation stage.

SWRCB

Back to Top

 
 

State Water Resources Control Board. A department in the California Environmental Protection Agency responsible for protecting public health, the environment and water resources through the regulation of water quality.


Jump Links: ABCDEFGHIJKLMNOPQRS T UVWXYZ Top


Term
  

TD

Back to Top

 
 

See: Total Depth.

Top of Horizon (MD-Feet)

Back to Top

 
 

Depth to the top of the production horizon, in feet, measured along the wellbore.

Top of Horizon (TVD-Feet)

Back to Top

 
 

True vertical depth, in feet, to the top of the production horizon.

Total Depth (TD)

Back to Top

 
 

The total depth of an oil or gas well, measured in feet, as measured depth (MD) or true vertical depth (TVD.)

Township

Back to Top

 
 

Used in the U.S. PLSS, a township is a square parcel containing 36 square miles of land, or a measure of distance north or south from a referenced baseline, in units of six miles.

Trade Name

Back to Top

 
 

Product name given by the manufacturer to an additive contained within the WST fluid.

Trade Secret Protection

Back to Top

 
 

Classification that protects certain information regarding WST additives from public disclosure.  ((See Pub. Resources Code, § 3160, subd. (j).)

True Vertical Depth (TVD)

Back to Top

 
 

Depth of an oil or gas well measured vertically from ground surface without reference to the wellbore path.


Jump Links: ABCDEFGHIJKLMNOPQRST U VWXYZ Top


Term
  

UG/L

Back to Top

 
 

Micrograms per Liter. Unit of measurement for water sample concentration, equal to one microgram of a substance dissolved in one liter of water.

UIC

Back to Top

 
 

Underground Injection Control. A Division program approved by the U.S. EPA pursuant to the federal Safe Drinking Water Act to regulate Class II injection wells.

UIC Project Number

Back to Top

 
 

A unique 8-digit code used by the Division to identify a project within the Class II Underground Injection Control program.


Jump Links: ABCDEFGHIJKLMNOPQRSTU V WXYZ Top


Term
  

Valid Value List

Back to Top

 
 

The list that provides standardized terms (usually abbreviated) for certain fields (e.g., analytical methods, chemical constituents, analytical laboratories, units). The analytical laboratory abbreviation list used for the SB 4 program is based on the valid values list used by the SWRCB for data submitted to their Geotracker website. http://geotracker.waterboards.ca.gov/ 

Volume Prior to Sampling

Back to Top

 
 

Volume, in barrels, of fluids recovered following well stimulation at the time of initial sampling (greater than 1 well volume, less than 3 well volumes).


Jump Links: ABCDEFGHIJKLMNOPQRSTUV W XYZ Top


Term
  

Water Supplier

Back to Top

 
 

The private individual, agent, or company that provided the base fluid water.

Well Designation

Back to Top

 
 

Well identifier used by the Division that consists of a combination of the lease name and the well ID.

Well ID

Back to Top

 
 

Well number designated by the well operator that appears within Division records.

Well Stimulation Treatment  (WST)

Back to Top

 
 

A treatment of a well designed to enhance oil and gas production or recovery by increasing the permeability of the formation.

WST Permit Number

Back to Top

 
 

Number assigned by the Division to an approved WST permit.

WST Start Date

Back to Top

 
 

Date WST was initiated.

WST End Date

Back to Top

 
 

Date WST was terminated.

 


Jump Links: ABCDEFGHIJKLMNOPQRSTUVWXYZ Top