After a well produces oil and gas, the produced hydrocarbons move through a production facility which may be
comprised of tanks, pressure vessels, pipelines, or other equipment, located at or near the oil field. Operators use
the equipment in a production facility to prepare produced oil and gas for sale to refineries or gas utilities by
removing solids, water, and other impurities. The Pipelines and Facilities Program in the Geologic Energy Management
Division (CalGEM) oversees operation of this equipment for compliance with applicable law.
Pipelines and facilities oversight is one of many pieces in CalGEM's mission to protect health, safeguard the
environment, and advance California's climate and energy goals in the regulation of oil and gas production within
the state.
The Pipelines and Facilities Program uses both engineering staff as well as field inspectors in each local CalGEM
district office to ensure that operations, maintenance, and removal or abandonment of oil and gas production
equipment and infrastructure comply with applicable statutes and regulations.
Generally, CalGEM regulates all pipelines and facilities located within or near an oil field. The Office of the State
Fire Marshal has jurisdiction over certain crude oil pipelines, most of which are located outside oil field
boundaries and used for transportation to refineries.
For Operators
Regulated Oil and Gas Facilities
Definition and Jurisdiction
CalGEM regulates all oil and gas production equipment between the wellhead, where oil or gas leaves the ground, and
the sales meter, where ownership or custody changes. CalGEM's jurisdiction extends to tanks, pumps, valves,
compressors, safety systems, separators, manifolds, pipelines, and other equipment attendant to oil and gas
production and injection operations.
Other entities, such as the Department of Industrial Relations or the local Fire Authority, have rules and
requirements that establish minimum design standards, construction standards, and operational requirements at the
production site, which provide a basic level of safety for workers and the public.
1, 2
CalGEM's statutes and regulations provide additional requirements regarding the production of oil or gas which apply
at the production site and in associated production facilities, prior to the oil or gas passing through the sales
meter.
Title 14 of the California Code of Regulations (Regulations) section 1773.2 contains requirements for
Tank Construction and Leak Detection.
Design Specifications
In most tanks and vessels, oil is separated from the water that is commonly produced during the
process of extracting oil from oil wells. All new tanks shall be constructed and designed to provide
enough space between tanks to allow safe access for maintenance, inspection, testing, and repair. New
tanks are those constructed on or after January 29, 2011. Two key components in tank construction are
foundation design and leak detection.
Foundation Design
Foundations for new tanks shall be designed to support the tank, maintain the tank level, and drain
fluid away from the tank, including fluids that may leak from the tank. It is important that fluids
drain away from the tank so that leaks can be identified immediately, before they cause environmental
damage.
For new tanks, the sub-base of the foundation shall include an impermeable barrier designed to prevent
downward fluid migration and to allow leaks to drain away from the tank. That way, leaks can be
detected by either visual inspection or a leak detection sensor.
Leak Detection
A leak detection system is required for all new tanks and when a tank bottom is replaced. The system
must either channel any leak beneath the tank to a location where it can be readily observed from the
outside perimeter of the tank, or accurately detect any tank bottom leak by the use of sensors. One
means of channeling leaks is installing grooves in a concrete foundation. These grooves allow leaking
fluid to flow outward beyond the tank's circumference where it can be seen.
To use sensors for leak detection, probes can be installed under the tank and connected to a
monitoring system. These probes are specifically designed to sense hydrocarbons and can be installed
to fulfill the leak detection requirement.
Regulations sections 1773.3 and 1773.4 provide requirements for Tank Maintenance and Inspections, and
Tank Testing and Minimum Wall Thickness Requirements. Regulations section 1777 addresses monitoring
and maintenance requirements applicable to all production facilities. Regulations section 1777.2
addresses operator reporting and notification requirements.
Tank Identification
CalGEM's WellSTAR database and WellFinder GIS program contains a list of tanks and vessels,
including the owners and locations of this equipment.
Tanks must be properly marked or have signage that shows:
- Operator's Tank Identification Number
- Tank Type (production, stock, water, etc.)
- Appropriate Materials Hazards Placard or Labels
Monthly Inspections
External visual inspections are required at least once a month on all in-service tanks associated with
oil and gas production. Operators shall inspect for the following:[EM1]
- Leakage at base, seams, associated piping, tank shell plugs, or any other fitting that could
leak.
- The presence of corrosion or shell distortions.[EM2]
- The general condition of the foundation, including any signs of
settling or erosion that may undermine the foundation.[EM3]
- The condition of paint coatings, insulation systems, and tank grounding system components, if
present.
- Any damage to secondary containment and the general condition of secondary containment systems.
- The open/closed status of rainwater drain valves.[EM4]
Monthly inspection findings shall be documented either on paper or electronically. The records shall
be maintained and easily accessible so that a CalGEM inspector can review them upon request.[EM5]
Wall Thickness Testing
California requires that the walls or sides of in-service metallic tanks be tested for thickness every
five (5) years, unless otherwise approved by CalGEM . Operators must notify the local CalGEM district
office at least two days prior to conducting required tank testing.
Operators often hire a tank inspection company to perform tank wall thickness testing, using
ultrasonic thickness-testing equipment. The tank inspection company visits the production facility to
measure the wall thickness in various places. Using the lowest thickness measured from the various
readings, an inspector can potentially determine the tank corrosion rate. If the corrosion rate can be
determined, inspection time intervals, subject to approval by CalGEM, may be extended, but must still
be done at least once every 15 years.
The minimum thickness for a tank shell is 0.06 inch.
Internal Inspection and Bottom Plate Testing
In-service metallic tanks shall be internally inspected and tested to determine bottom plate thickness
no less than once every 20 years. A tank is exempt from this requirement if:
- The tank is not an environmentally sensitive tank, it is not in an urban area, and is not
located above subsurface fresh water; or
- The sub-base of the foundation of the tank has an impermeable barrier designed to prevent
downward fluid migration and to allow leaks to drain away from the tank; or
- The tank has a properly installed, operating, and maintained leak detection system.
Inspectors usually use ultrasonic thickness testing equipment to perform internal inspection and
bottom plate thickness testing. For bottom-plate thickness testing, an inspector will take readings at
various places. The smallest thickness measured from the various readings determines if the plate is
still usable. The minimum bottom plate thickness shall meet the following criteria:
- 0.10 inch for tank bottom/foundation design with no means of detection and containment of a
bottom leak;
- 0.05 inch for tank bottom/foundation design with adequate leak detection and containment of a
bottom leak;
- 0.05 inch in conjunction with a reinforced tank bottom lining,
greater than 0.05 inch thick.
Testing and Inspection for Non-metallic Tanks and Metallic Tanks with Liners
Non-metallic tanks and metallic tanks with liners require inspections and tests according to the
manufacturer's specifications or as requested by CalGEM.
Footnotes:
1. The California Department of Industrial Relations, Division of Occupational Safety and Health
(CalOSHA) also regulates tanks and pressure vessels. Please see Title 8 of the California Code of
Regulations for further information, available at this link:
Cal/OSHA - Title 8 regulations - Table of Contents.
2. The National Fire Protection Association (NFPA) prescribes requirements for the storage, handling,
and use of flammable and combustible liquids. These requirements are enforced by local authorities.
Please see NFPA 30, Flammable and Combustible Liquids Code, for further information, available at this
link:
NFPA 30, Flammable and Combustible Liquids Code,.
Regulated Oil and Gas Pipelines
Regulations sections 1774, 1774.1, and 1774.2 provide requirements for pipeline construction, testing, and
maintenance. Regulations section 1777.2 addresses operator reporting and notification requirements.
CalGEM regulates all oil and gas pipelines between the wellhead, where oil or gas leaves the ground, and the
sales meter, where ownership or custody changes. The pipelines regulated by CalGEM transport crude oil, liquid
hydrocarbons, combustible gases, and produced water. Newly installed pipelines shall be designed, constructed,
and all pipelines shall be tested, operated, and maintained in accordance with good oil field practice and
applicable standards. All aboveground pipelines must be inspected annually for leaks and corrosion. Any active
pipeline that has a
reportable
release must be taken out of service, repaired, and must pass pressure testing before it is reactivated and
returned to service.
All newly installed, repaired, or modified existing pipelines must be tested prior to starting
or re-starting operations. Any pipeline having a leak of reportable quantity must successfully
pass pressure testing before returning to service. Additionally, CalGEM-regulated pipelines must
be
tested on a periodic basis. Active oil or gas pipelines located in
high-risk areas, such as environmentally sensitive, urban, and
sensitive areas, require biennial testing after reaching the age of 10 years. Acceptable testing
methods include pressure testing, ultrasonic, and smart pigging. Approval from CalGEM is
required before using a testing method other than pressure testing or ultrasonic testing to
determine wall thickness. CalGEM recommends operators seek input from CalGEM when planning an
ultrasonic test of a pipeline located in a high-risk area ( NTO 2019-09).
Operators may conduct pipeline leak inspections per Regulations sections 1774.1(a) and (b)
without notification to CalGEM, as this activity is not considered testing. Furthermore,
pipelines not located within high risk areas must be tested at a minimum per the interval
specified by
Cal-OSHA. Operators must
notify the local CalGEM district office at least two days prior to any required pipeline
testing. CalGEM does not require notification of testing for pipelines not located within high
risk areas, unless these pipelines are tested following a repair due to a reportable leak.
Optional pressure-test data collection template
Revised Pipeline Management Plan (PMP) requirements became effective on October 1, 2018. PMPs are
required for all operators and must be updated to include
all pipelines, except those pipelines abandoned per Regulations section 1776.
PMPs must be updated within 90 days whenever pipelines are installed or altered, or at request
of the Supervisor.
Some larger operators may have existing line lists showing required PMP data. These line lists
may meet some pipeline information requirements and can be referenced in the PMP. For operators
relying on a line list to meet any PMP requirements, a current electronic copy must be provided
to CalGEM.
Operator PMP Template
Environmental
Protection
Regulations sections 1722, 1722.9, 1773.1, and 1775 provide requirements regarding environmental protection
during oil and gas production.
Three components of CalGEM's environmental protection program are spill contingency plans, secondary
containment measures, and the use of sumps and catch basins. Each operator must prepare and submit a Spill
Contingency Plan documenting prevention and response to unauthorized releases of fluid and other substances.
Secondary containment is an engineered impoundment that is designed to capture fluid released from an oil or gas
production facility, such as a tank or vessel. A sump or pit is an open excavation used for collecting or
storing fluids used or produced from oil and gas operations. A catch basin is a dry sump that is constructed to
protect against unplanned overflow conditions.
A spill contingency plan (SCP) outlines an operator's measures for controlling, containing, and
recovering an oil or water release. An approved SCP includes provisions for rapid deployment of
containment and recovery equipment; it lists the initial steps the operator will take in the
event of a spill, the equipment the operator has on hand to control the spill, phone numbers
that the operator will call to inform other agencies of the spill, and details the training that
staff working for the operator undergo to prepare for and prevent spills. SCPs include maps
showing the location and contents of all tanks and pipelines at a production facility, and the
location of structures present to contain spills.
Spills shall be reported immediately to the California Office of Emergency Services (OES) at
(800) 852-7550. OES will notify CalGEM's local district office. However, if a spill happens
outside regular business hours, operators should notify the local CalGEM district office
directly.
The U.S. Environmental Protection Agency (EPA) requires a Spill Prevention Countermeasure and
Control Plan (SPCC) from oil and gas operators as part of its oil spill prevention program. An
operator's SPCC may satisfy spill contingency plan requirements if the SPCC has all of the
elements required by CalGEM for inclusion in the SCP and is determined by CalGEM to be adequate.
Secondary containment is an engineered impoundment or confinement, such as a wall, berm, or catch
basin, designed to capture fluid released from a production facility. A leak or spill may
release large amounts of oil, and secondary containment must be capable of containing the
equivalent volume of liquids from the single piece of equipment at a production facility with
the largest gross capacity within the secondary containment. Containment is intended to confine
the liquid and prevent it from entering streams, lakes, the ocean, homes, streets, and more.
Secondary containment allows for a quick clean-up after a leak or spill.
All oil and gas facilities that store or process fluids must have secondary containment measures
in place. Valves, headers, manifolds, pumps, compressors, wellheads, pipelines, flowlines, and
gathering lines are excluded from the secondary containment requirement.
A secondary containment's floor surface area and wall or berm must be capable of confining liquid
for a minimum of 72 hours. Materials of construction are chosen by the operator. Soils
considered for containment area construction can be verified to be acceptable via permeability
testing performed by a soils engineering firm. Also, if soil is used for a berm, the addition of
a heavy-duty plastic sheeting or shotcrete can be considered to improve durability.
Any damage to the secondary containment, such as cracks, erosion, or animal borrows shall be
repaired immediately.
Sumps/Pits
Regulations section 1770 provides the requirements for Oilfield Sumps.
A sump or pit is an open excavation that collects or stores fluids. There are three types of
sumps:
- Drilling Sump - used with drilling operations
- Operations Sump - used with well rework or abandonment operations
- Evaporation Sump - a pit containing fresh or saline water for evaporation
A catch basin is a dry sump constructed to protect against unplanned overflow conditions. While
also a type of sump, a catch basin is considered a secondary containment measure because it
functions in tandem with primary containment measures.
Location:
- Sumps for the collection of wastewater or oil are not permitted in natural drainage
channels. Contingency catch basins may be permitted, but they shall be evacuated and cleaned
after any spill.
- Unlined evaporation sumps, if they contain harmful waters, shall not be located where they
may be in contact with freshwater aquifers.
- Operators should be aware that sumps must also comply with applicable State Water Resources
Board and local air pollution control district requirements in addition to CalGEM
requirements.
Construction: Sumps shall be designed, constructed, and maintained so as to not be a hazard to
people, livestock, or wildlife including birdlife.
- To protect people, sumps in urban areas must be enclosed by a chain link fence, and gates
must be locked.
- In non-urban areas, to protect people and livestock and to deter wildlife, an enclosure
shall be constructed around sumps with wire fencing.
- Any evaporation sump which contains oil or a mixture of oil and water shall be covered with
screening to restrain entry of wildlife.
- A sump need not be individually fenced if the property or the production facilities of which
the sump is part is enclosed by proper perimeter fencing.
Drilling Sumps: All free fluids must be removed from drilling sumps within 30 days after the
date the drill rig is disconnected from the well.
Operations Sumps: All fluids shall be removed from operations sumps within 14 days after the rig
removal or from completion of operations, whichever occurs first.
Out-of-Service Surface Production Facilities and Removal
Regulations section 1773.5 contains requirements for Out-of-Service Production Facilities, and Regulations
section 1776 contains requirements for Well Site and Lease Restoration. Regulations section 1777.2 addresses
operator reporting and notification requirements.
Out-of-Service production facility equipment, such as tanks, vessels, or pipelines can no longer safely contain
fluid or operate as designed. CalGEM has prescribed specific requirements for the maintenance, inspection, and
decommissioning of Out-of-Service equipment. The requirements for managing Out-of-Service production equipment
are below.
Facilities, Tank, and Pipeline Status Chart
When a piece of production facility equipment such as a tank, vessel, or pipeline is determined
to be Out-of-Service, the following actions must be completed within six months:
- All fluids, sludge, hydrocarbons, and solids shall be removed. Production facilities shall
be disconnected from any pipelines and other in-service equipment.
- The facility shall be degassed in accordance with local air district requirements.
- Clean-out doors or hatches on out-of-service tanks shall be removed and heavy gauge steel
mesh grating (less than 1” spacing) shall be secured over the opening to allow for visual
inspection and prevent unauthorized access.
- Tanks and vessels shall be labeled “Out-of-Service” or “OOS.” The label shall be painted in
bold letters, at least one (1) foot high and at least five (5) feet off the ground, on the
side of the tank or vessel, along with the date it was taken out of service.
- Valves and fittings shall be removed or secured to prevent unauthorized use.
- Pipelines associated with Out-of-Service tanks and pressure vessels shall be removed or
flushed, filled with an inert fluid (such as nitrogen ), and blinded.
No Out-of-Service production equipment shall be put back In-Service until all repairs are
completed and the facility is in compliance with all applicable testing and inspection
requirements. Operators shall notify the local district office within 60-days after completing
new construction, alteration, or decommissioning of a production facility, or reactivating an
Out-of-Service tank.
Prior to the plugging and abandonment of the last well or group of wells on a lease, the operator
shall submit a plan and schedule for completing lease restoration. Following the conclusion of
operations on the lease, the well site must be restored to as near a natural state as possible.
The Lease Restoration Plan (the Plan) shall include the locations of any existing or previously
removed sumps, tanks, pipelines, or facility settings, where known.
Lease restoration shall include the removal of all tanks, above-ground pipelines, debris, and
other facilities and equipment.
Remaining buried pipelines shall be purged of oil and filled with an inert fluid (such as
water). Toxic or hazardous materials shall be removed and disposed of in accordance with
Department of Toxic Substances Control requirements.
Lease restoration work must begin within three (3) months and be completed within one year after
the plugging and abandonment of the last well(s) on the lease.
There is not a specific format for the Plan. However, it must contain and cover how all the
elements discussed here will be removed and how the well site will be restored.
Mapping, GIS, and
WellSTAR
Mapping the locations of pipelines, tanks, and vessels is an ongoing project at CalGEM. In accordance with
Regulations section 1774.2 (Pipeline Management Plans), operators are required to maintain a list and maps of
all pipelines that indicate which lines pass through sensitive areas, environmentally sensitive areas, urban
areas, and designated waterways. Regulations section 1760 contains definitions of sensitive areas and
environmentally sensitive areas.
New rulemaking is underway that will require operators to submit mapping information and locational data,
including pipeline characteristics, in digital form for active gas pipelines in sensitive areas and oil
pipelines in environmentally sensitive areas. This information will be added to CalGEM's Pipeline Mapping System
(CPMS), a Geographic Information System (GIS) that CalGEM developed and maintains to assist with regulating high
risk pipelines. CPMS is part of CalGEM's electronic well data management system called WellSTAR, which stands
for Well Statewide Tracking and Reporting.
Using WellSTAR, operators can also review and update the location of tanks and vessels associated with their
operations. This information can be viewed on maps that access CPMS and other CalGEM GIS information. CalGEM's
objective is to locate and map all production facilities associated with oil and gas operations in California,
and, along with their basic characteristics, identify them within GIS and WellSTAR.
Operators are encouraged to use WellSTAR to review production facility data for their operations, update as
needed any existing data, and input any new or missing data.