JOGMEC’s guideline for safe, long-term
containment of CO2 using CO2-EOR(JOGMEC CO2-EOR Guideline)

Published June 2023
Japan Organization for Metals and Energy Security（JOGMEC）

Contents
1

Introduction ........................................................................................................................1
1.1

Background and objectives ...........................................................................................1

1.2

Contents of the guideline..............................................................................................2

1.3

Scop of the guideline ...................................................................................................3

1.3.1

Scope of projects ..................................................................................................3

1.3.2

Scope of project stages .........................................................................................3

1.3.3

Scope of a spatial boundary...................................................................................4

1.4

Features of the guideline ..............................................................................................5

1.4.1

Effect of reduction in GHG emissions with CO2-EOR .............................................5

1.4.2

Technical recommendations for safe and long-term containment of CO2 in association

with CO2-EOR....................................................................................................................62

3

Project planning and operations of CO2 storage projects in association with CO2-EOR ............8
2.1

General remarks and fundamental concepts ...................................................................8

2.2

Documentation ............................................................................................................8

2.3

Information gathering for the preparation of the EOR operations management plan ..........8

2.4

Preparation of the EOR operations management plan .....................................................9

2.5

Risk management ......................................................................................................10

2.6

Monitoring ................................................................................................................11

2.7

Well infrastructures....................................................................................................12

2.8

Record keeping and missing data ................................................................................12

2.9

Project termination ....................................................................................................12

Quantification of reduction in GHG emissions of CO2 storage projects in association with CO2-

EOR ........................................................................................................................................14
3.1

General remarks and fundamental concepts .................................................................14

3.2

Quantification of reduction in GHG emissions .............................................................14

3.2.1

Quantification of CO2 storage amount based on ISO27916 ....................................15

3.2.2

Emissions associated with fuel and power consumptions (scope 1 and scope 2) ......16

3.2.3

Methane leakage from an EOR site boundary .......................................................17

3.2.4

Quantification of reduction in GHG emissions......................................................17

3.3

Measurements during CO2-EOR operations .................................................................19

4

References .......................................................................................................................22

5

Appendix .........................................................................................................................24

1

Introduction

1.1

Background and objectives

For the energy transition toward the realization of carbon neutrality by 2050, a comprehensive
approach that considers the social and economic impacts on people’s lives is necessary. The
International Energy Agency (IEA) stated that the transition to clean energy must be advanced alongwith the efforts to provide energy access for all people by 20301. Fossil fuels that enable stable andmassive power generation continue to play an important role in smooth energy transitions. Althoughfossil fuels emit greenhouse gases (GHGs) during combustion, it is possible to mitigate climate change
when they are combined with carbon dioxide (CO2) capture and storage (CCS), where the emitted CO2
is captured and sequestrated in subsurface formations.
To promote better use of fossil fuels that contributes to climate change mitigation, Japan Organization
for Metals and Energy Security (JOGMEC) published the following two guidelines in May 2022:“CCS guideline (1st version)” and “GHG/CI guideline (1st version).” The former guideline isconcerned with technical guidance on a CCS project and quantification of net CO2 reduction with a
CCS project2, while the latter is concerned with the quantification of the reduction in GHG emissions
associated with the production of liquefied natural gas (LNG), hydrogen, and ammonia3.
Following these publications, JOGMEC has recently started the development of the guideline for CO2enhanced oil recovery (CO2-EOR) in which CO2 is injected into a hydrocarbon reservoir to enhancehydrocarbon recovery from the reservoir.
There are several opinions on whether CO2-EOR contributes to the mitigation of climate change by
reducing GHG emissions. It is believed that CO2-EOR does not contribute to a reduction in GHG
emissions because it produces additional oil4. For this, Clean Air Task Force (CATF) introduced theconcept of displacement. Based on the global oil market analysis by IEA, CATF proposed that
additional oil produced with CO2-EOR does not increase the global oil supply; instead, it displaces theoil produced using conventional methods, from the market while maintaining a certain level of global
oil supply determined from global demand. They concluded that every barrel of oil produced with
CO2-EOR reduced CO2 emissions by 37% compared to oil produced using conventional methods5.
Others have claimed that the life-cycle emissions of CO2-EOR projects could be net-positive. Because
CO2-EOR produces oil while injecting CO2 if the amount of GHG emissions associated with the
combustion of the produced oil exceeds the amount of CO2 stored, the life-cycle emissions of such a
CO2-EOR project result in positive emissions. However, recently, several researchers and EOR
operators have shown that the life-cycle emissions of CO2-EOR projects can be net negative if the1

projects are properly designed to improve the efficiency of CO2 storage6,7.
Moreover, the most remarkable feature of CO2-EOR is that it reduces GHG emissions while generating
revenue from the oil produced. Hence, CO2-EOR facilitates a sustainable and smooth energy transition
because it achieves both CO2 sequestration and energy production, yielding economic incentives thatenable an operator to proceed with further development of decarbonization technologies. This feature
is particularly important for countries that need to cope with their growing energy demand. Several
countries have encouraged the implementation of CO2-EOR.
Considering the aforementioned points, JOGMEC views CO2-EOR as an effective means of reducing
GHG emissions and encourages its implementation during a period of energy transition toward adecarbonized society. Nevertheless, such CO2-EOR can contribute to a reduction in GHG emissions
only when a project is properly planned and executed with the objective of safe and long-term
containment of CO2.
Hence, JOGMEC started the preparation of guidelines for CO2-EOR contributing to a reduction in
GHG emissions. These guidelines have the following four objectives:⚫

To state JOGMEC’s view on CO2-EOR, i.e., we consider CO2-EOR to be an effective means of
GHG reduction during the energy transition period, and we encourage its implementation.

⚫

To provide technical guidance for the implementation of CO2-EOR projects that contribute to a
reduction in GHG emissions and for the quantification of emission reductions by such projects.

⚫

To provide technical guidance that is recommended to be satisfied by companies for receiving
financial and/or technical support from JOGMEC for such projects.

⚫

To help interested business entities and regulators design their business models and regulations
to reduce the carbon intensity of energy fuels through safe and long-term storage of CO2.

1.2

Contents of the guideline

This guideline provides technical recommendations for project planning and operations of CO2-EOR
that are conducted for safe and long-term containment of CO2, and quantification of the reduction in
GHG emissions with such projects. Sections 1.3 and 1.4 provide the scope and features of theguidelines, respectively.
Section 2 describes the details of the project planning and operations of CO2 storage projects inassociation with CO2-EOR, and Section 3 provides a methodology to quantify the amount of reduction
in GHG emissions that can be achieved with these CO2-EOR projects.

2

To formulate the guidelines, we considered the views of international organizations, financial
institutions, and government agencies on whether CO2-EOR can be regarded as a useful GHG
emission reduction measure. Furthermore, to consider the technical recommendations for safe andlong-term storage of CO2, we referred to the rules and regulations of the countries and regions wherelaws and regulations for safe and long-term storage of CO2 and the technical requirements of various
systems that deal with carbon credits and tax incentives in association with CO2-EOR are in place(Appendix 1).

1.3

Scope of the guideline

1.3.1 Scope of projects
This guideline is designed for a project in which CO2 is injected into hydrocarbon reservoirs with dual
objectives of “enhanced hydrocarbon recovery” and “safe and long-term containment of CO2.” The
guideline covers CO2-enhanced oil and gas recovery (CO2-EOR and CO2-EGR) projects that
contribute to reducing GHG emissions. Hereafter, the terms CO2-EOR and EOR refer to both CO2EOR and CO2-EGR.
Projects that do not recover hydrocarbon resources from a target reservoir from the beginning of the
project are beyond the scope of this guideline (e.g., CO2 injection in saline aquifers and in depleted
oil/gas reservoirs). For these types of projects, please refer to the JOGMEC’s CCS guideline2.
1.3.2 Scope of project stages
The scope of the project stages of this guideline covers the pre-injection to post-injection periods, as
shown in Figure 1. The definitions of each project stage are as follows.
⚫

Pre-injection period: the project period before the injection of CO2 into the reservoir begins.
During this period, hydrocarbon production from the project reservoir without CO2 injection is
performed normally.

⚫

During the injection period: the project period from the time at which CO2 injection in a target
reservoir begins to the time at which both CO2 injection and hydrocarbon production cease. In
this guideline, regardless of natural CO2 or anthropogenic CO2, as long as CO2 injection occurs,such a project stage belongs to this period. Even if the CO2 injection ceases, if production takes
place in a project reservoir, the project stage belongs to this period.

⚫

Post-injection period: The project period after the cessation of both injection and production of
CO2 till the time approved by the local project authority for the termination of the project.*⚫

Post-termination period: The period after the time approved by the local project authority for thetermination of the project.

⚫

Quantification period: The project period during which the reduction in GHG emissions is3

quantified. This period begins after the injection of CO2 by an EOR operator and ends at thetermination of the EOR project with the approval of a local authority.

Figure 1: Scope of project stages of this guideline (prepared by JOGMEC)(NOTE) The beginning of the post-injection period: This guideline defines the beginning of the postinjection period as the time at which both CO2 injection and hydrocarbon production cease. In general,
the following three cases are considered for a typical CO2-EOR project: (1) both production andinjection cease, (2) production continues while injection ceases, and (3) production ceases while
injection continues; hence, the project transforms into CCS. This guideline covers all three cases.
1.3.3 Scope of a spatial boundary
In this guideline, the spatial boundary of a CO2-EOR project is defined to include the following surface
and subsurface elements, as shown in Figure 2.
⚫

CO2 reception and injection facilities (including storage tanks, etc.)⚫

Processing and storage facilities for the oil produced.

⚫

Processing facilities for the produced gas (including CO2 recovery units)⚫

Target subsurface geological formations (EOR complex*)(NOTE) EOR complex: This is the same as defined in ISO279168, that is, subsurface formations
composed of at least one target reservoir formation where CO2 is injected and the cap rock formationacts as a barrier.

4

CO2transferred

CO2 supply

CO2-EOR Site boundary

CO2 received

Processing of
associated gas(CO2 separationand capture)

Recycled CO2

Sales gas(for EGR)
Produced gas

Injection
Processing ofproduced fluid
Injector(s)(Recommended to adopt
the closed loop system)

Sales oil

Producer(s)Figure 2: Scope of a spatial boundary of this guideline (prepared by JOGMEC).
Within the spatial boundary of the CO2-EOR project in this guideline are the CO2 reception andinjection facilities, CO2 injector(s), hydrocarbon producer(s), and processing facilities for the
produced fluid (oil, gas, and water). In some projects, the received CO2 is transferred to other CO2EOR projects located outside the boundary. In some cases, the outgoing CO2 from the boundary
contains the transferred CO2 stream. If the received CO2 has sufficient pressure, there is no need for
an injection facility. As the configuration of EOR facilities varies on a project-by-project basis, thespecific spatial boundary is determined by an EOR operator who reviews each component of the
facilities relevant to an EOR project.
GHG (CO2 and CH4) emissions from the elements constituting the EOR project are measured. In
addition, any input from outside to inside the boundary is measured. For instance, GHG emissions
associated with fuel consumption by the pumps and/or compressors within the boundary are measured.

1.4

Features of the guideline

1.4.1 Effect of reduction in GHG emissions with CO2-EOR
Compared with CO2 storage in saline aquifers and/or depleted oil/gas reservoirs, CO2-EOR has a lower
contribution to the reduction in GHG emissions because it produces hydrocarbons that can, in turn,contribute to CO2 emissions (Scope 3 emissions with CO2-EOR projects). However, there is aconsensus that CO2-EOR safely stores a certain amount of CO2 within an EOR complex, that is, acertain amount of injected CO2 remains in the EOR complex for a long period, with several trapping
mechanisms, such as capillary trapping, solubility trapping, and structural trapping.
Another opinion is that CO2-EOR does not contribute to a reduction in GHG emissions because it
produces hydrocarbons. For this, Clean Air Task Force (CATF) introduced the concept of displacement,

5

that is, additional oil produced with CO2-EOR does not contribute to additional GHG emissions
because it displaces crude oil in the global market whose amount remains within a certain range(because the amount is determined from the balance between demand and supply)5. The concept of
displacement has been employed in several institutes, such as the American Carbon Registry (ACR)9
and Alberta Emission Offset System (AEOS)10. JOGMEC also supports the concept of displacementand drafts this guideline.
Based on the above, in this guideline, JOGMEC considers the safe and long-term containment of CO2
associated with CO2-EOR as an effective means of GHG reduction, at least during the period of energy
transition toward a decarbonized society.
1.4.2 Technical recommendations for safe and long-term containment of CO2 in association
with CO2-EOR(1) General technical recommendations
As technical recommendations for the safe and long-term containment of CO2 in association with CO2EOR, these guidelines recommend planning and operating CO2-EOR projects in compliance with
ISO279168 which is an international standard for CO2-EOR. Furthermore, these guidelines provide
additional technical recommendations for ISO279168.
(2) Scope of the quantification of reduction in GHG emissions
Following the concept described in the JOGMEC CCS guideline2, the scope of the quantification of
the reduction in GHG emissions in this guideline includes Scope 1 and Scope 2 emissions associatedwith a CO2-EOR project, where GHG refers to CO2 and CH4. N2O is excluded from the definition of
GHG in this guideline because its amount of emission is much lower than that of CO2; however, if
there is combustion equipment in an EOR boundary, it is recommended to confirm that the amount ofN2O emissions is sufficiently small compared to that of CO2 by direct measurements.
(NOTE)
Scope 1 emissions: Direct GHG emissions by the project operator (fuel combustion).
Scope 2 emissions: Indirect GHG emissions associated with the supplied power and heat/steam fromoutside the EOR boundary.
(3) Improving storage efficiency
A CO2-EOR project, designed mainly to maximize the recovery of hydrocarbons from a project
reservoir, produces hydrocarbons while injecting CO2. Hence, it is necessary to allow the outgoing
CO2 from an EOR boundary as entrained CO2 in the hydrocarbon. The amount of CO2 (entrained CO2

6

in the hydrocarbon, oil, and/or gas stream) must be quantified and subtracted from injected CO2amount to determine the net CO2 stored.
When an EOR operator aims at high CO2 storage efficiency, it is recommended to consume all the
produced hydrocarbon gas within the EOR boundary or to employ a closed-loop system that iscommonly applied in onshore CO2-EOR projects in the U.S11. In a closed-loop system, all the
produced gas streams are directly transferred to the injection stream without separation from theproduced gas stream. Hence, all produced gas streams are compressed and used for re-injection fromthe injectors. As this creates a closed loop between the surface facilities and a subsurface reservoir, it
has been reported that 90–95% of the received CO2 is securely stored within an EOR complex11.
(4) Expandability of CO2-EOR projects
In a CO2-EOR project, the efficiency of CO2 storage changes as the EOR process progresses. The
project maintains a high CO2 storage efficiency from the beginning of CO2 injection until theoccurrence of CO2 breakthrough to producers. After the CO2 breakthrough, the efficiency of CO2
storage decreases as the concentration of CO2 in the produced gas stream increases. However,regardless of the progress of the EOR process, because an agreed amount of CO2 from an emitter is
continuously delivered to the EOR site, a CO2-EOR project must have sufficient expandability toreceive the agreed amount.
Examples of a CO2-EOR project that has expandability are projects that are connected to other EOR
and/or CCS sites via CO2 transportation pipelines and a project that is developed by a phased approachin which a vast EOR site is gradually developed by applying a flooding pattern (composed of a set of
producers and injectors). For these types of projects, it is recommended that the CO2 storage capacityof each EOR site should be evaluated before CO2 injection, based on reservoir simulations.
It should be noted that for a project that is connected to other EOR sites and/or CCS sites via CO2transportation pipelines, multiple CO2 sources (emitters) and multiple CO2 sinks (EOR/CCS
operators) are connected via pipelines; hence, attempts to monitor and verify the supply-demandbalance of the entire system of pipelines will be important in the future.
(5) Post-injection monitoring
For CO2-EOR projects designed for safe and long-term CO2 containment, it is strongly recommended
to perform post-injection monitoring for a certain duration during the post-injection period.

7

2

Project planning and operations of CO2 storage projects in association with CO2-EOR

2.1

General remarks and fundamental concepts

In many countries and regions, CO2-EOR is executed under the existing regulations for the explorationand production of oil and gas. However, when an operator executes a CO2-EOR project with theobjective of safe and long-term CO2 containment in addition to enhanced hydrocarbon recovery, theseprojects must satisfy the requirements to ensure safe and long-term CO2 containment, in addition to
the requirements defined by the regulations for the exploration and production of oil and gas. If an
operator executes an EOR project in a region where rules and regulations for safe and long-term CO2
containment are in place, compliance with these rules and regulations is recommended.
In this guideline, to ensure safe and long-term containment of CO2, in principle, it is recommended tocomply with ISO27916. The guidelines provide additional recommendations for ISO27916 in thefollowing sections. To consider these additional recommendations, we referred to other rules for thesafe and long-term containment of CO2 such as ISO2791412 (international standard for geologicalsequestration of CO2), ACR, Clean Development Mechanism (CDM), and rules by the Environmental
Protection Agency (EPA) of the U.S. (UIC Class II and VI13, and the reporting requirement of subpart
RR14).

2.2

Documentation

For the execution and operation of a CO2-EOR project, it is recommended to prepare and maintain all
the documents relevant to the CO2-EOR project comply with clauses 4.1_ 4.4 in ISO27916.
[Reference: ISO27916 4.1 _ 4.4]
In addition, although clause 4.3 in ISO27916 requires the preparation of an EOR operation
management plan, initial containment assurance, and monitoring program as initial documentation, it
is recommended that an initial termination plan also be prepared and revised depending on the progressof the project.

2.3

Information gathering for the preparation of the EOR operations management plan

For the preparation of the EOR operations management plan, it is recommended to gather and analyze
the following information in compliance with clauses 5.1_ 5.5 in ISO27916.
⚫

General description of the CO2-EOR project (geology of the EOR complex, facilities, wellinfrastructure, development history).

⚫

Geological characterization and containment assessment of the EOR complex.

⚫

Description of facilities within the CO2-EOR project.

⚫

Existing wells within the EOR complex

8⚫

Operations history of the project reservoir[Reference: ISO27916 5.1_5.5]
In addition, the guideline recommends the followings:⚫

The level of information required to characterize the geology and assess the containment of CO2
in the EOR complex is the level at which a geological and reservoir simulation model can beconstructed.

⚫

In many CO2-EOR projects, subsurface data have been acquired during the historicalhydrocarbon development period before CO2-EOR begins. However, if these data are notsufficient to characterize the geology and assess the containment of CO2 in the EOR complex,
acquiring new data (e.g., drilling evaluation wells) before CO2 injection is recommended.

⚫

It is recommended to prepare a process flow diagram (PFD) that includes facilities within a CO2EOR project and describes the flow of CO2 and produced oil and gas. In the PFD, it isrecommended that the locations of venting, fluid sampling, and metering should be clearly
described. The metering of fluids is particularly important for quantifying the amount of net CO2
stored; hence, it is recommended to clearly describe the metering method and its accuracy.

⚫

It is recommended to investigate all existing wells within an EOR complex and gather
information on the latest status of these wells (wellhead and wellbore) as much as possible. In
cases where it is difficult to evaluate the current status of the wells from historical well records,
it is recommended to conduct on-site surveys of these wells to gather their information.

2.4

Preparation of the EOR operations management plan

In the preparation of the EOR operations management plan, it is recommended that the procedures forfield management be clearly described, as described in (a)–(i) in Clause 6.1.1 of ISO27916.
[Reference: ISO27916 6.1.1]
In addition, the guideline recommends the following:⚫

(Expandability of a CO2-EOR project) It is recommended to ensure that the EOR operations
management plan can stably accept the agreed amount of CO2 stream over the project period. It
is recommended that the CO2 storage capacity of a project is recommended to be evaluated basedon reservoir simulation models before CO2 injection.

⚫

(Simulation models) It is recommended to construct geological and reservoir models and plan
projects based on the geological characterization and containment assessment of the EOR
complex using these models [ACR 5.4.1.3].

⚫

(Improving predictability) Before CO2 injection, it is recommended that the best effort be madeto improve the predictability of the CO2-EOR project by performing history matching of the9historical hydrocarbon production period using the aforementioned models. During the CO2
injection period, it is recommended to continue periodic model revisions [ACR 5.4.1.3].
⚫

(Risk management and monitoring plan) It is recommended to prepare a risk management plan(see Section 2.5) based on risk assessment and a monitoring plan (see Section 2.6).

⚫

(Post-injection monitoring) It is recommended to plan and conduct “during-injection monitoring”
and “post-injection monitoring” for a certain period (see Section 2.6).

⚫

(Termination plan) It is recommended to prepare an appropriate plan for project termination to
enable smooth liability transfer from an EOR operator to a local authority while ensuring safeand long-term CO2 containment (see Section 2.9). In particular, caution is required in EOR
projects that are implemented based on regulations related to the exploration and production ofoil and gas. An EOR project has to be terminated not only upon fulfilling the requirements in theregulations but also upon fulfilling the requirements to ensure safe and long-term CO2
containment.

2.5

Risk management

A risk-management plan should be prepared based on the identification of potential CO2 leakage
pathways and their risk assessments. It is strongly recommended to conduct risk management
assessment as a part of containment assurance in compliant with clauses 6.1.2 _ 6.1.3 in ISO27916 as
follows:⚫

Initial containment assurance⚫

Operational containment assurance[Reference: ISO27916 6.1.2 ~ 6.1.3]
In addition, the guideline recommends the followings:⚫

(Identification of potential CO2 leakage pathways) It is recommended to identify potential CO2
leakage pathways through the site characterization based on the construction of geologicalmodels and reservoir simulations [ACR 5.4.1.2]. If the identified risks exceed the allowable limit,
the EOR site is excluded from the candidate list.

⚫

(Well integrity assessment) It is recommended that a list of wells be prepared for all existing wells
located within an influence zone. This influence zone is determined by considering the expected
spread of CO2 (including the spread of the CO2 plume and pressure disturbance) and other risks
specific to an EOR project. It is recommended that the list of wells should include the current
status, how and when they are completed, information relevant to plugs and abandonments, andavailable cement bond logs [ACR 5.4.1.2]. If it is not possible to prepare a list of all existingwells located within an influence zone, the reasons for this should be described.

⚫

(Well integrity assessment and remediation) It is recommended to define technical requirements10

to ensure the integrity of wells and to conduct an assessment of well integrity to check if all wells
satisfy the requirements. For wells in which issues in integrity are identified, it is recommended
to plan countermeasures to recover their integrity and execute those before CO2 injection where
necessary. Examples of countermeasures are well remediation and monitoring of leakage [ACR
5.4.1.2]. If it is not possible to perform a integrity assessment for all existing wells locatedwithin an influence zone, the reasons for the same have to be described.
⚫

(Natural and induced seismicity) It is recommended to exclude an area from a candidate site fora project, in cases where significant seismic activities are observed compared to other areas andwhere it is not possible to acquire background data relevant to seismic activities before CO2
injection [JOGMEC CCS guideline chapter 2, 2.2]. During the operation of CO2-EOR, it isrecommended to devise and maintain surface seismic arrays to distinguish operation-related
induced seismicity from natural seismicity [LCFS15 4.3.2.3].

2.6

Monitoring

The objectives of monitoring are mainly classified into two categories: (1) ensuring safe and longterm containment of CO2 and (2) providing evidence for the quantification of reduction in GHG. Here,
we describe the monitoring of the former objective, while that of the latter is described in Section 3.3.
It is strongly recommended to plan and conduct monitoring to ensure safe and long-term containmentof CO2 in compliance with clauses 6.2.1_6.2.3 of ISO27916 as follows:⚫

Monitoring of potential leakage pathways⚫

Monitoring methods⚫

Monitoring program implementation[Reference: ISO27916 6.1.2_6.1.3]
In addition, the guideline strongly recommends the following:⚫

(Monitoring requirements equivalent to those for CCS) It is recommended to make monitoringplans equivalent to those for CO2 storage in geological formations, that is, it is recommended toprepare a monitoring plan in compliance with clause 9 of ISO27914 which is an international
standard for CO2 storage in geological formations. Hence, it is recommended to plan and conduct
the monitoring for at least the following three periods.
➢

Pre-injection period monitoring：[ISO27914 9.2.2]➢

During-injection period monitoring：[ISO27914 9.2.3]➢

Post-injection (Closure) period monitoring：[ISO27914 9.2.4]

For the selection of specific monitoring techniques, it is recommended to choose cost-effective
techniques by referring to the best practices of former CCS projects. Examples of specific11monitoring techniques are provided in clause 6.4 in the JOGMEC CCS guidelines.
⚫

(Acquisition of baseline data) While ISO27914 requires the acquisition of baseline data before
CO2 injection, in case such data is difficult to acquire, it is recommended to propose how torigorously determine baseline data.

⚫

(Use of well data) EOR operations involve fluid production from the producers, unlike CO2
storage in geological formations. Data acquisition on the amount of produced fluid, temperature,and pressure is normally conducted as a part of normal EOR operations. These data can be usedthrough history matching using the simulation model described in Section 2.4 to evaluate thespread of the CO2 plume and the pressure disturbance. It is recommended to use these production
data for monitoring.

2.7

Well infrastructures

It is highly recommended to construct new infrastructure in compliance with clause 7.1 of ISO27916.
It is strongly recommended that an operator ensure the placement of proper cement for long-term CO2
containment, at least in the cap rock section.
[Reference: ISO27916 7.1gh]
It is highly recommended to conduct well intervention in compliance with clause 7.2 of ISO27916.
[Reference: ISO27916 7.2]
It is strongly recommended that, during the transition period toward a decarbonized society, as
described in Section 1.1, all new wells involved in a CO2-EOR operation must comply with existing
standards used for the exploration and production of oil and gas (e.g., API standards, UIC Class II in
the U.S.) [ACR 5.4.1.2]. Additionally, it is strongly recommended that mechanical integrity andcorrosion protection tests should be conducted periodically. It is also recommended that an operator
aims to comply with well requirements equivalent to UIC Class VI in the future.

2.8

Record keeping and missing data

It is recommended to maintain records relevant to CO2-EOR operations in compliance with clause 9.1
in ISO27916 and to prepare for submission to a local authority upon request after the termination of
the project. If it is difficult to acquire actual measured data, it is recommended to describe a method
to estimate missing data in compliance with clause 9.2 of ISO27916.
[Reference: ISO27916 9.1 ~ 9.2]

2.9

Project termination

It is recommended to terminate a project in compliance with clause 10.1_10.6 of ISO27916 as follows:12⚫

General⚫

Periodic assurance of containment⚫

Termination plan⚫

Requisites for termination⚫

CO2-EOR project termination⚫

Post-termination[Reference: ISO27916 10.1_10.6]
In addition, the guideline recommends the following:⚫

(Requirements for project termination) For the termination of CO2-EOR that enables safe andlong-term containment of CO2, it is recommended to fulfil not only the requirements set by alocal authority that deal with hydrocarbon development but also the requirements that ensure safeand long-term containment of CO2.

⚫

(Requirements ensuring containment of CO2) In case a CO2-EOR project occurs in a region wherea local authority has requirements ensuring safe and long-term containment of CO2, and the
project is executed in compliance with these requirements, it is recommended to terminate theproject in accordance with the requirements.

⚫

(Requirements ensuring containment of CO2) In case a CO2-EOR project occurs in a region wherea local authority does not have requirements ensuring safe and long-term containment of CO2,
and the project is executed under the regulations for hydrocarbon development, in principle, it isrecommended to terminate the project following the project termination plan which describes thedetails corresponding to a) _ e) of the clause 10.4 in ISO27916. In particular, if a project achieves
these conditions, these must be confirmed and verified through post-injection monitoring(NOTE1). The requirements for and duration of post-injection and post-termination monitoring
are recommended to be discussed and agreed upon among the relevant stakeholders (NOTE2)
before CO2 injection, and these requirements should be documented as an initial termination plan.

(NOTE 1) Currently, the majority of CO2-EOR projects are executed onshore in the United States
under the rules of UIC Class II, which do not aim for long-term CO2 containment. If an operator
terminates a project under the rules of UIC Class II, the operator loses the right to enter the EOR site,making it impossible for the operator to conduct post-injection monitoring. Even in such a case, it isrecommended to conduct post-injection monitoring as described in the note in Section 1.3.2, i.e., (2)a case in which production continues, while injection ceases, and (3) a case in which production ceases,
while injection continues, hence, the project transforms to CCS.
(NOTE 2) The relevant stakeholders include at least the following:

13

➢

An EOR operator and a local authority who is responsible for the EOR project.

➢

A CO2 supplier if a CO2-EOR project contributes to the reduction of GHG emissions of the
supplier.

3

Quantification of reduction in GHG emissions of CO2 storage projects in association with
CO2-EOR

3.1

General remarks and fundamental concepts

Section 3 provides guidance for the quantification of the reduction in GHG emissions with CO2-EOR
which aims at the safe and long-term containment of CO2.
To quantify the reduction in GHG emissions, this guideline recommends quantifying the amount of
net CO2 stored in compliance with clause 8 of ISO27916. In addition, this guideline describes how toquantify the emissions associated with fuel and power consumption in an EOR boundary and theleakage of CH4 from an EOR boundary.
Methodologies to quantify the reduction in GHG emissions with CO2-EOR are currently being actively
discussed and investigated by several institutes worldwide, and they differ for each CO2-EOR project
depending on the location and characteristics of the project. Hence, the methodologies described inthis guideline represent JOGMEC’s current view on this matter (during the transition to a decarbonizedsociety). JOGMEC will continue to review and improve the content of the guidelines as necessary.

3.2

Quantification of reduction in GHG emissions

It is recommended that the amount of net CO2 is stored in compliance with clause 8 of ISO27916.
Clause 8 in ISO27916 provides the CO2 that is counted as storage and the CO2 that is subtracted fromstorage (for instance, the loss of CO2). Although, in many cases, when the received CO2 from outside
an EOR boundary is injected into a target reservoir, GHG emissions such as loss, flare, and venting at
the facilities of injection, processing of produced streams, etc., must be subtracted to derive the netCO2 storage. The types of CO2 considered in this guideline are compliant with the following:⚫

CO2 to be included in storage amount:[Reference: ISO27916 1.3.1]⚫

CO2 to be excluded from storage amount:[Reference: ISO27916 1.3.2]

In addition, this guideline recommends quantifying the following to derive the reduction in GHG
emissions:⚫

Scope 1 and scope 2 emissions within an EOR boundary⚫

CH4 leakage from an EOR boundary. Note that because CO2 leakage from an EOR boundary is
counted by the methodology to quantify net-CO2 storage in clause 8 of ISO27916, it is not14

included here.
(NOTE) JOGMEC Guidelines on Quantification of CO2/GHG Emissions and Carbon Intensity.
JOGMEC published “GHG/CI guideline (1st version)” in May 2022. This guideline provides thequantification of reductions in GHG emissions associated with the production of liquefied natural gas,hydrogen, and ammonia. The GHG/CI guidelines aim to provide accurate and rigorous methodologies
to quantify the level of emissions based on the estimation using emission intensity and activity amountand/or the estimation combining direct measurement and material balance method. Please refer to the
GHG/CI guidelines for the specific methodologies used for these estimation methods.
3.2.1 Quantification of CO2 storage amount based on ISO27916
Clause 8 in ISO27196 provides methodologies for quantifying the amount of net-CO2 storage(𝑚stored) by subtracting the amount of operational loss and leakage from an EOR complex from theamount of CO2 received (CO2 input), which is given by𝑚stored = 𝑚input − 𝑚loss operations − 𝑚loss EOR complex
where 𝑚input denotes the CO2 input, 𝑚loss operations denotes the operational loss, and𝑚loss EOR complex denotes the leakage from an EOR complex. The parameters required to determine
these quantities are described in the following sections of ISO27916.
⚫

General[Reference: ISO27916 8.1]⚫

Quantification principle[Reference: ISO27916 8.2]⚫

Quantification of input[Reference: ISO27916 8.3]⚫

Quantification of loss

[Reference: ISO27916 8.4.1_8.4.5]⚫

Quantification of leakage from an EOX complex[Reference: ISO27916 8.4.6]

In this guideline, only anthropogenic CO2 is considered as the amount of net-CO2 storage. The
definition of anthropogenic CO2 in this guideline is the same as that in ISO 27916. If a project deals
with both anthropogenic and non-anthropogenic CO2, the amount of anthropogenic CO2 must be
allocated based on the methodology described in clause 8.5 in ISO27916.
⚫

Definition of anthropogenic CO2[Reference: ISO27916 3.1]⚫

Allocation ratio for anthropogenic CO2[Reference: ISO27916 8.5]

Table 1 provides examples of anthropogenic CO2 considered in this guideline. It is highly
recommended to discuss and agree on the anthropogenic portion of CO2 of a project before CO2
injection with relevant stakeholders*.

15

(NOTE) The meaning of “relevant stakeholders” is the same as described in Section 2.9.
Table 1: Examples of the scope of CO2 that is included or excluded in this guideline
ExamplesScope

CO2 produced as a by-product of combustion and chemical

Included in CO2 storage

processes.

quantification(e.g., recovered CO2 from post combustion exhaust gas from power
plants,recovered

CO2

from

chemicalprocessesofammonia/hydrogen production.)
CO2 produced from subsurface reservoirs in association with

Included in CO2 storagehydrocarbon development.

quantification(e.g., separated CO2 from hydrocarbon gas stream containing highCO2 concentration)
CO2 produced from subsurface reservoirs only for the purpose

Excluded from CO2 storageof use of CO2.

quantification(e.g., produced CO2 from subsurface CO2 reservoirs such as theJackson Dome in the U.S.)
In a CO2-EOR project, recycled CO2 from the produced fluids is mixed with CO2 received fromoutside the EOR boundary, pressurized to the injection pressure, and re-injected into a target reservoir
from the injectors. After the CO2 breakthrough for producers, the gas associated with crude oil
production contains a high concentration of CO2. Hence, it is necessary to properly recover and reinject
this produced CO2. The gas stream after the separation of CO2 contains mainly methane, and it ispossible to send it to the market as sales gas. However, even after CO2 separation, because thisoutgoing gas contains CO2, the storage efficiency of a project can decrease, which contradicts theobjective of CO2 storage. Hence, this guideline recommends adopting a closed-loop system that iscommonly used in projects in the onshore U.S. If an EOR operator sells the associated gas after the
separation of CO2, it is necessary to quantify the amount of CO2 entrained in the sales gas and outgoingfrom the EOR boundary.
3.2.2 Emissions associated with fuel and power consumptions (scope 1 and scope 2)
The scope of the power and heat/steam to be counted depends on the facilities and flow scheme ofeach project. Hence, it is recommended to clarify the scope of power and heat/steam to be counted
during the project planning stage (pre-injection period) to avoid double counting and omission of GHG
emissions. Once CO2 injection begins (during the injection period), it is recommended to monitor the16

status of operations to verify whether the actual emissions are consistent with the planned emissions.
3.2.3 Methane leakage from an EOR site boundary
Leakages from an EOR site boundary are classified into two types:1) intended releases based on an
operation plan, such as flares and vents, and 2) unintended releases, such as leakages and emergency
releases. This guideline recommends quantifying the amount of CH4 leakage from an EOR siteboundary since CO2 leakage is covered in clause 8 of ISO27916.
3.2.4 Quantification of the reduction in GHG emissions
The quantification of the reduction in GHG emissions associated with a CO2-EOR project (Figure 3)
is given by the following equation: The details of each term in the equations are listed in Table 2.
[Reduction in GHG emissions associated with CO2-EOR project]= [CO2 storage amount based on ISO27916]− [Emissions associated with fuel and power consumption (Scopes 1 and 2)]− [Methane leakage from the EOR site boundary]

Figure 3: Schematic of a typical CO2-EOR project (prepared by JOGMEC).

17

Table 2: Quantification of the reduction in GHG emissions in association with a CO2-EOR project.
Term
Reduction

Descriptions
inthe

GHG emissions in

Reduction in the GHG emissions that is achieved by a CO2-EOR project
designed for safe and long-term containment of CO2

association with a
CO2-EOR project
CO2 storage amountThis is determined based on the clause 8 of ISO27916. Annex B in

based on ISO27916

ISO27916 provides an example of this calculation, please refer to this fordetails.
In case emission intensity and activity amount are used, please refer to thechapter 2 of JOGMEC’s GHG/CI guideline (version 2), recommended
methodology at the site (such as EPA Subpart W16, etc.) or commonly
recognized methodologies. The unit of CO2 storage amount is “ton”.

Emissions

The total of the following emissions associated with CO2 receipt,

associated with fuelcompression, processing of produced fluids, CO2 recycling, monitoring, etc.

and

power

consumptions (scope
1 and scope 2)(1) Direct CO2/GHG emissions associated with fuel combustion (forgeneration of power and heat/steam).
This is Scope 1 emission and please refer to the chapter 2 of JOGMEC’s
GHG/CI guideline (version 2)(2) Indirect CO2/GHG emissions associated with purchased electricity (forgeneration of power and heat/steam).
This is Scope 2 emission and please refer to the chapter 2 of JOGMEC’s
GHG/CI guideline (version 2)

Methaneleakage

Intended releases of methane such as flare and vent occurring at CO2

from an EOR site

recovery and other facilities, methane leakage occurring during the process

boundaryof compression, transportation, and injection (only in case methane is used
for fuel gas).
This is determined based on emission intensity. Please refer to the chapter
2 of JOGMEC’s GHG/CI guideline (version 2), recommended methodology
at the site (such as EPA Subpart W16, etc.) or commonly recognizedmethods.

GHG: greenhouse gas; EGR: enhanced gas recovery; EOR: enhanced oil recovery

18

3.3

Measurements during CO2-EOR operations

Depending on the purpose, the required level of accuracy for measuring the amount of CO2 within an
EOR site boundary varies. Although there is no established international standard for measurementswith a clear description of the required level of accuracy, this guideline recommends the following
measurements, as listed in Table 3.

19

Table 3: Summary of the recommendations for measurement.
Parameters

Unit

Frequency

Comment

Gas flow rate, CO2

Nm3/d

⚫

⚫

concentration andCO2 flow rate at
custody%⚫

transfer

meters (M1 andContinuous for gas flowrate.

chromatography at an appropriate point close to the custody transfer meter toPreferable to measure gas

measure gas composition.

composition at every 3_5
ton/d

⚫

minutes but depending on

M2, plus M5 for

Measure gas flow rate at a custody transfer meter and install a gas

a project.

CO2-EGR projects)

Correct measured flow rate withpressure and temperature; and try to avoid

using estimated composition and density which are not based on measurements.
⚫

Install flow meters in accordance with guidance by a vendor.

⚫

Place flow meters at least at the point of M1 and M2 for CO2-EOR projects andplus M3 for CO2-EGR projects. No need to place at M5 if a closed loop system
is employed.

⚫

Make calibration and inspection of flow meters periodically in accordance withspecifications by a vendor and/or regulations by a local authority.

⚫

Obtain CO2 flow rate in mass unit (ton/d) from volumetric flow rate obtained
from gas flow rate and CO2 concentration.

Gas flow rate, CO2

Nm3/d

⚫

concentration andCO2 flow rate at%

operational meters(M3 and M4)⚫

Continuous for gas flow

Measure gas flow rate at operational flow meters, collect fluid samples fromrate.

sampling points located close to the flow meters, and conduct gas composition

Periodic gas composition

analysis on the samples.

measurement based on
ton/d

⚫

laboratory

analysiscollected samples.

⚫

on

Correct measured flow rate with pressure and temperature; and try to avoid using
estimated composition and density which are not based on measurements.

⚫

Install flow meters in accordance with guidance by a vendor.

20

⚫

The frequency of analysis⚫

Place flow meters at least at the point of M3 and M4.

depends on a project.

⚫

Make calibration and inspection of flow meters periodically in accordance withspecifications by a vendor and/or regulations by a local authority.

⚫

Obtain CO2 flow rate in mass unit (ton/d) from volumetric flow meter obtained
from gas flow rate and CO2 concentration.

Oil flow rate, CO2

ton/d

⚫

concentration andCO2 flow rate at
custody%⚫

transfer

meters (M6)

Continuous for oil flow⚫

Install flow meters in accordance with guidance by a vendor.

rate.

⚫

Make calibration and inspection of meters periodically in accordance with

Periodic composition andspecifications by a vendor and/or regulations by a local authority.

density measurement at aton/dfrequency required fromoil custody transfer

Water flow rate,

ton/d

⚫

CO2 concentration
and CO2 flow rate%⚫

at water disposal(M7)

Continuous for water flow⚫

Install flow meters in accordance with guidance by a vendor.

rate.

⚫

Make calibration and inspection of flow meters periodically in accordance with

Periodic

composition

measurement based on
ton/dlaboratory⚫

analysisspecifications by a vendor and/or regulations by a local authority.
⚫

onMeasure the composition and density based on analyses performed on collected
samples; and use measured CO2 concentration as a representative value.

collected samples.

⚫

Locate sampling points close to metering points.

The frequency of analysis⚫

In case water flow rate measurement is not conducted, make periodical

depends on a project.

measurement of CO2 concentration in water to ensure the amount of CO2 in waterremains at a sufficiently low level.

GHG: greenhouse gas; EGR: enhanced gas recovery; EOR: enhanced oil recovery

21

4
1.

References
Bouckaert S, Pales AF, McGlade C, Remme U, Wanner B, Varro L, D'Ambrosio D, Spencer T.
IEA. Net Zero by 2050: A Roadmap for the Global Energy Sector. Int. Energy Agency 224(2021).

2.

JOGMEC. JOGMEC announces the publication of the first version of a recommended guideline
for the implementation of carbon dioxide capture and storage projects.
https://www.jogmec.go.jp/english/news/release/news_10_00004.html (2022).

3.

JOGMEC. JOGMEC announces the publication of the first version of a recommended guideline
for greenhouse gas and carbon intensity accounting framework for LNG／Hydrogen／Ammonia
project. https://www.jogmec.go.jp/english/news/release/news_10_00005.html (2022).

4.

Núñez-López, V. & Moskal, E. Potential of CO2-EOR for Near-Term Decarbonization. Front.
Clim. 1, (2019).

5.

Clean Air Task Force. CO2EOR Yields a 37% Reduction in CO2 Emitted Per Barrel of Oil
Produced. 1–2 https://cdn.catf.us/wpcontent/uploads/2019/06/21093723/CATF_EOR_LCA_Factsheet_2019.pdf?swpmtx=8d2051ab
555c3f04350d1fe486f37bee&swpmtxnonce=a487638577 (2019).

6.

IEA. Storing CO2 through enhanced oil recovery: Combining EOR with CO2 storage (EOR+)
for profit. (2015).

7.

Nuñez-Lopez, V., Gil-Egui, R., Hosseininoosheri, P., Hovorka, S. D. & Lake, L. W. Carbon Life
Cycle Analysis of CO2-EOR for Net Carbon Negative Oil (NCNO) Classification (Final Report).
https://www.osti.gov/servlets/purl/1525864 (2019) doi:10.2172/1525864.

8.

International Organization for Standardization. ISO27916 Carbon dioxide capture, transportationand geological storage — Carbon dioxide storage using enhanced oil recovery (CO2-EOR). First
edit, 13 (2019).

9.

American Carbon Registry. Methodology for the quantification, monitoring, reporting andverification of greenhouse gas emissions reductions and removal from carbon capture andstorage projects. Version 1.1. 1–75 at https://americancarbonregistry.org/resources/carboncapture-and-storage-primer (2021).

10.

Alberta Energy. Quantification Protocol for Enhanced Oil Recovery. Version 2.0. at
https://www.alberta.ca/alberta-emission-offset-system.aspx#jumplinks-3 (2022).

11.

Melzer, L. S. Carbon dioxide enhanced oil recovery (CO2 EOR): Factors involved in adding
carbon capture, utilization and storage (CCUS) to enhanced oil recovery. (2012).

12.

International Organization for Standardization. ISO27914 Carbon dioxide capture,transportation and geological storage — Geological storage. vol. First edit (2017).

13.

Environmental Protection Agency. 40 CFR Part 146 Underground Injection Control Program:22

Criteria and Standards. https://www.ecfr.gov/current/title-40/chapter-I/subchapter-D/part146?toc=1 (2022).
14.

Environmental Protection Agency. 40 CFR Part 98 Subpart RR Geologic Sequestration of
Carbon Dioxide. https://www.ecfr.gov/current/title-40/chapter-I/subchapter-C/part-98?toc=1(2022).

15.

California Air Resources Board. Carbon Capture and Sequestration Protocol under the Low
Carbon Fuel Standard. 1–139 at https://ww2.arb.ca.gov/sites/default/files/202003/CCS_Protocol_Under_LCFS_8-13-18_ada.pdf (2018).

16.

Environmental Protection Agency. 40 CFR Part 98 Subpart W Petroleum and Natural Gas Systems.
https://www.ecfr.gov/current/title-40/chapter-I/subchapter-C/part-98?toc=1 (2022).

1.

IEA. Net Zero by 2050: A Roadmap for the Global Energy Sector. Int. Energy Agency 224(2021).

2.

JOGMEC. JOGMEC announces the publication of the first version of a recommended guideline
for the implementation of carbon dioxide capture and storage projects.
https://www.jogmec.go.jp/english/news/release/news_10_00004.html (2022).

3.

JOGMEC. JOGMEC announces the publication of the first version of a recommended guideline
for greenhouse gas and carbon intensity accounting framework for LNG／Hydrogen／Ammonia
project. https://www.jogmec.go.jp/english/news/release/news_10_00005.html (2022).

4.

Núñez-López, V. & Moskal, E. Potential of CO2-EOR for Near-Term Decarbonization. Front.
Clim. 1, (2019).

5.

Clean Air Task Force. CO2EOR Yields a 37% Reduction in CO2 Emitted Per Barrel of Oil
Produced. 1–2 https://cdn.catf.us/wpcontent/uploads/2019/06/21093723/CATF_EOR_LCA_Factsheet_2019.pdf?swpmtx=8d2051ab5
55c3f04350d1fe486f37bee&swpmtxnonce=a487638577 (2019).

6.

IEA. Storing CO2 through enhanced oil recovery: Combining EOR with CO2 storage (EOR+) for
profit. (2015).

7.

Nuñez-Lopez, V., Gil-Egui, R., Hosseininoosheri, P., Hovorka, S. D. & Lake, L. W. Carbon Life
Cycle Analysis of CO2-EOR for Net Carbon Negative Oil (NCNO) Classification (Final Report).
https://www.osti.gov/servlets/purl/1525864 (2019) doi:10.2172/1525864.

8.

International Organization for Standardization. ISO27916 Carbon dioxide capture, transportationand geological storage — Carbon dioxide storage using enhanced oil recovery (CO2-EOR). First
edit, 13 (2019).

9.

American Carbon Registry. Methodology for the quantification, monitoring, reporting and23verification of greenhouse gas emissions reductions and removal from carbon capture and storage
projects. Version 1.1. 1–75 at https://americancarbonregistry.org/resources/carbon-capture-andstorage-primer (2021).
10.

Alberta Energy. Quantification Protocol for Enhanced Oil Recovery. Version 2.0. at
https://www.alberta.ca/alberta-emission-offset-system.aspx#jumplinks-3 (2022).

11.

Melzer, L. S. Carbon dioxide enhanced oil recovery (CO2 EOR): Factors involved in adding
carbon capture, utilization and storage (CCUS) to enhanced oil recovery. (2012).

12.

International Organization for Standardization. ISO27914 Carbon dioxide capture, transportationand geological storage — Geological storage. vol. First edit (2017).

13.

Environmental Protection Agency. 40 CFR Part 146 Underground Injection Control Program:
Criteria and Standards. https://www.ecfr.gov/current/title-40/chapter-I/subchapter-D/part146?toc=1 (2022).

14.

Environmental Protection Agency. 40 CFR Part 98 Subpart RR Geologic Sequestration of Carbon
Dioxide. https://www.ecfr.gov/current/title-40/chapter-I/subchapter-C/part-98?toc=1 (2022).

15.

California Air Resources Board. Carbon Capture and Sequestration Protocol under the Low
Carbon Fuel Standard. 1–139 at https://ww2.arb.ca.gov/sites/default/files/202003/CCS_Protocol_Under_LCFS_8-13-18_ada.pdf (2018).

16.

Environmental Protection Agency. 40 CFR Part 98 Subpart W Petroleum and Natural Gas
Systems. https://www.ecfr.gov/current/title-40/chapter-I/subchapter-C/part-98?toc=1 (2022).

5

Appendix

Appendix 1: Technical requirements defined in different schemes that include CO2-EOR as a mean of
CO2 storage (as of December 2022)

24

Disclaimer
JOGMEC strives to post as accurate information as possible regarding this guideline but does not necessarily guarantee
the accuracy and completeness of the content. Please note that JOGMEC is not responsible for any damage incurred asa result of following these guidelines.

25Appendix 1
Appendix 1: Technical requirements defined in different schemes that include CO2-EOR as a mean of CO2 storage (as of December 2022)
NOTE: The American Carbon Registry (ACR) is a voluntary carbon offset program; The Clean Development Mechanism (CDM), defined in Article 12 of the Protocol, allows a country with an emission-reduction or emission-limitation commitment
under the Kyoto Protocol (Annex B Party) to implement an emission-reduction project in developing countries; EPA Class II plus Subpart RR is the requirements for CO2 enhanced oil recovery in the US in the 45Q Tax Credit1; EPA Class VI plus
Subpart RR is the requirement for CO2 geologic sequestration in the US in the 45Q Tax Credit1; the Alberta Emission Offset System (AEOS) is a regulatory program that enables facilities regulated under the Carbon Competitiveness Incentive
Regulation to purchase and retire emission offsets to meet compliance obligations.
The following table is modified from Gupta and Cumming, 2016 2 with reference to the original documents for each rule.
ACR:

CDM:

American Carbon Registry3

Clean

Development

Mechanism,

Modalities and Procedures for CCS4
Risk⚫

File Risk Mitigation Covenant or⚫

Perform risk and safety assessment

Assessment

similar, including ACR right to accessfor the entire CCS chain (not justand Mitigation

property to conduct inspections [ACR

storage),

1.2].

reflect monitoring data.

⚫

⚫

updatedEPA Class VI plus Subpart RR:

Protocol for AEOS:

Environmental Protection Agency (EPA)

Environmental Protection Agency (EPA)

Quantification Protocol for EOR for AEOS7

Class II5 plus Reporting via Subpart RR6Class VI5 plus Reporting via Subpart RR6(Alberta Emission Offset System)⚫

Subpart RR requires:
➢

to

⚫

Delineate

themonitoringarea

maximum
–

the

area

Subpart RR requires the same as on⚫

the left.
⚫

UIC

Class

Establishaassessment
VI

has

its

will

allow

for

thorough risk management throughoutandphase CO2 plume until injectedassessment and mitigation as follows:

response plans to stop or control

CO2 is not expected to migrate in➢

5.4.1].

unintended CO2 emissions or leakage

the future in a manner likely toseismic history and a tabulation

Develop a catalog of wells penetrating(F. Participation requirement).

result in surface leakage orof all wells within the area of

Perform environmental and socio-

release [§ 98.448].

review [§ 146.82];

reviews new and existing wellbores

Identify all artificial penetrations

within 1.6 km beyond the CO2 fluid

maximumthat may penetrate the confining

plume to assess for and manage risks

monitoring area and assess thezone and either confirm thatover the life of the CO2-EOR storage

potential storage failure scenarios,

likelihood, magnitude, and timing,

those have mechanical integrity if

approval.

considering a range of uncertainty for

of

CO2

operational or have been properly

parameters and site characteristics

through[§plugged. Corrective action must

metres of a proposed injection well

[ACR 5.4.1.1].

98.448].

be performed on any artificial

may need to be abandoned as per

penetrations that could serve as

Directive 020.

leakagepathwaysandremediate

where

possible

[ACR

⚫

⚫

Developremedial

measuresmonitor wells with leakage potential

economic

impact[ACR 5.4.1.2].

periodically

updatedUndertake a simulation study ofmonitoring data.

assessments,
toreflect➢

Identify potential surface leakage
pathwaysinsurfacetheleakagetheseofpathways➢

Prepareinformation

to

that

risk

requirements

Identify

relevant

original

site-specificexpected to contain the freeat or near the injection zone; repair or⚫

periodically

EPA Class II plus Subpart RR:

on

risk

➢

storage and remediation strategies incase of loss of containment.
⚫

⚫

⚫

A wellbore risk assessment that

Any high-risk offset wells within 100

A hazard assessment evaluating thepotential for induced seismicity within

data collected [§146.84 c];the maximum CO2 plume extent andTake into account any geologic

the applied for CO2 EOR storage

heterogeneities,

scheme approval area.

othertheir possible impact on model
predictions [§146.84 c]; andConsiderpotential

migration

through faults, fractures, andartificial penetrations [§146.84 c].

26

assess the risks associated withBe based on detailed geologic

discontinuities, data quality, and

➢

⚫

the

leakage pathways [§ 146.84 c].
➢the life of scheme approval,

Appendix 1
Pre-Injection⚫

Characterizationand Monitoring

Operator has the option to decide if⚫

pre-injection data is needed [5.4.1.3].
⚫

⚫

Storage volume expected to contain

Perform

monitoringtoestablish⚫

baseline data.
⚫

Assessall

Subpart RR requires:
➢

known

and

inferred⚫

Define a strategy for setting

Subpart RR requires the same as on⚫

Satisfy the following requirements as

the left.

defined in Directive 065: Containment

UIC Class VI requires to define AoR

Assurance,

Safety,leakage [§ 98.448].

based on computational modeling that

Suspension&

Define a strategy for detecting

accounts

Reporting.

monitoring baselines for surface

⚫

Well

CO2, plume extent and duration of

structures within the injection and cap

plume migration must be assessed via

rock formations for risk of migration of

the use of a reservoir model and flow

injected CO2 via a 3D reservoir modeland quantifying any CO2 surface

chemical properties of all phases

simulations [ACR 5.4.1.1].

(Appendix B).

leakage [§ 98.448].

present [§ 146.84].

project application should

UIC Class VI specify:➢

Identify

leakagepathwaysand⚫

Assess the injected CO2 fate and➢⚫

UIC Class II defines AoR by either the

⚫

for

the

physicalandremediate where possible. Operator

migration, with a particular focus on

Theis’s analytical equation or a fixedmust develop a detailed catalog ofvetting for risks of seepage to surface.

value greater than ¼ mile.

as defined in 146.86, which

UIC Class II requires:

includewells penetrating at or near the⚫

Developainjection zone and proceed to repair or

preparation,

monitor wells with leakage potential[ACR 5.4.1.2].

⚫

⚫

monitoring
well

plan,

site

⚫

the

requirements

injection rates and pressures, O&M

inject into a formation separated

and cementing, and tubing andprotocols,

andfrom any USDW by a confining

packer [§ 146.86].

management of site closure based onzone that is free of known open

the results of the above fluid flow andsimulation study.

timingextensive

logging,

faults or fractures within AoR withsampling,

andtesting

cased and cemented (146.22).

requirements prior to injection

Appropriate logs and other tests

well operation as defined in [§matching and use the monitoring data

shall be conducted during the146.87].

to calibrate and update numerical

drilling and construction (146.22).

Describe the process for history➢

thestorage

capacity➢

develop models and execute
simulations to predict the extent
of the CO2 fluid plume,➢

predict the behaviour of thehydrocarbon-CO2 phase,

Detailed➢defineestimates and injectivity,forgeneral well construction, casing➢

Abandonment,

In addition to the above, a CO2-EOR

Well construction requirements

Well construction designed toandconstruction,➢⚫

Integrity,➢

confirm

thattheproposedscheme will perform effectively
and safely,➢

establishasite-specificrisk

assessment that will allow for

Under UIC Class VI, preparing 3D

thoroughmodels.

computational models is compulsory

throughout the life of scheme

Monitoring plan must be periodicallyto fulfil the requirements for theapproval,

updated to reflect the analysis of thedelineation of AoR and the risk

monitoring data.

assessment [§ 146.84].

⚫

➢

risk

management

establish baseline conditions todesignandimplementamonitoring program, and➢assess the risks associated withstorageandremediation

strategies in case of loss of➢During-Injection⚫

Monitoring

Use a fluid flow model to periodicallyIdentify monitoring technologies, location,compare material balances for fluids

and sampling frequency to enable:

implement an EPA-approved MRV

as observed and predicted [ACR

1. Assurance of environmental integrity

plan that includes the following five5.4.1.3].
⚫

Undertake a simulation study ofpotential storage failure scenarios,

Subpart RR requires to develop andmajor components [§ 98.448]:

and safety.
2. Detection and estimation of quantity of

1.

CO2 stored in site.

considering a range of uncertainty for3. Confirmation that injected CO2 isparameters and site characteristics

contained and behaving as predicted.

[ACR 5.4.1.3].

⚫

4. Detection

andestimation

of

the

Delineation

of

the

monitoring

area,

⚫

⚫

Subpart RR requires the same as on

Conduct monitoring to:

the left.

⚫

UIC Class VI specifies:➢

maximum

andactiveIdentification

of

the

potential

surface leakage pathways and an

27➢

Demonstratelegislation

The requirements for operational

directives),

injection pressure which shall not

approvals.

exceed 90 percent of the fracture

monitoring areas;2.

containment.

⚫

compliance(regulations,withstandards,

applications

andMonitor for trigger events and, if

pressure of the injection zone(s)detected,[§ 146.88].

operating procedures in response.

The requirements for mechanicalemployassociatedAppendix 1⚫

Perform monitoring for the mostrate/mass of CO2 seepage either via

assessment of the likelihood,integrity of wells including theMonitoring technologies are evaluated on asensitive parameters as identified

cap rock, overburden and surrounding

magnitude, and timing of surface

demonstration of the absence ofregular basis

from the above study. Tools selecteddomains or via wells with potential forleakage of CO2 through thesesignificant

and sampling frequency must be

leakage.

pathways;temperature or noise logging at

The MMV plan is periodically renewed andleast once per year [§ 146.89].

ongoing dialogue is held with the regulator

specified (justified) [5.4.1.3].
⚫

5. Monitoringmeasurementof

Select and locate (other) monitoring

relevant parameters of groundwaterequipment in a manner that provide

properties,

confidence in CO2 storage and identify

concentrations measurements, etc.

leakage.

Establish

reasonable[ACR 5.4.1.3].

soil

and

surface

3.

CO2

4.

5.

CO2 seepage.

for

detectionand➢through

The detailed requirements for

Approach for establishing thetesting and monitoring in [§expected baselines; and146.90].

Considerations made to calculate
site-specific variables for the

7. Measurement of temperature at the top

Require the project-specific MRV planandbe developed by a professional [ACR

observation wells.

5.4.2].

Strategyquantification of surface leakage;

6. Timely remedial action in the event ofdetection thresholds for the equipment

⚫

and

leaks

bottomofinjection

andmass balance equation.
⚫

UIC Class II requires:➢

8. Detection of corrosion or degradation

Operational injection pressurewhichof transport and injection facilities.

shall

not

exceedamaximum that does not initiate
newfracturesor

propagate

existing fractures (146.23).
➢

Monitoring

of

the

natureofinjected fluids and observation of
injection pressure, flow rate, andcumulative volume at a minimum(146.23).
Post-Injection
Monitoring⚫

Minimum of 5 years of Post-⚫

Minimum of 20 years of Post-⚫

Subpart RR requires to develop andInjection. If no migration of the

Injection. If no migration of theimplement an EPA-approved MRV

injected CO2 is detected and theinjected CO2 is detected and theplan as described above [§ 98.447].

modelled failure scenarios indicate

modelled failure scenarios indicatethat CO2 remains contained within thethat CO2 remains contained within thestorage volume, then it is consideredstorage volume, then it is consideredadequate

adequate

assurance

that

no

assurance

that

⚫

⚫

Subpart RR requires the same as on⚫

the project operator to develop athe left.

termination plan for the CO2-EORUIC Class VI requires the default

project

UIC Class II has no description onvalue of 50 years of Post-Injection

termination.

post-injection site care.

site care.

developed any time after CO2 injection

⚫

➢

no

The

post-injection

specifies
This

plan

criteria

for

shall

be

care

begins, but must be developed prior toperiod can be reduced upon

the termination of CO2 injection at thescheme.

atmospheric leakage has occurred.

atmospheric leakage has occurred.

showing

Otherwise, monitoring requirements

Otherwise, monitoring requirements

monitoring and other site- specificwill be extended in 2-year increments

will have to be extended in 10 year

data,

until no leakage is identified [ACR

increments

sequestration project no longer

5.4.1.4].

assured.

poses

Monitoring is for the same parameters

USDWs," and the period will befacilities and perform all closure

described for “During Injection”.

extended if that demonstration

activities in accordance with theAn evaluation must be performed incannot be made even at the end

regulations.

the event of seepage to determine theof 50 years [§ 146.93].

⚫

⚫

until

no

leakage

is

28

that

site

that

that
an

"basedtheon⚫

geologicendangerment

toRegulatory

Framework

Assessment recommend minimum
10 years8⚫

⚫

Continue to monitor all wells andArrangements are made between theAppendix 1
quantity of seepage for compensation➢

purposes.

Specific monitoring methods andregulator and project operator for thetools should be site specific andtransfer of any

designedfollowing

equipment that the regulator requests

objectives: 1) verify plume is

to be left in place at the point of closurestabilizing and pressures arethat will not compromise long-term

equilibrating and 2) detecting

integrity of well abandonments.

for

the

MMV monitoring

potential leakage [§ 146.93].
Reporting/⚫

Accounting

ACR

detailsto

Subpart RR requires facilities to collectbaseline

include an accounting for all GHG

quarterly data and submit annual reports

emissions, project emissions, andemissions as a part of the baselineon the annual amount of CO2 sequestered.

Documentation for the Baseline condition

emission reductions in Equations 4.1

assessment

monitoring.

The mass balance equations RR-11 or RR-

requiresto 4.3 [ACR, 4.1~4.3].

Verification will be achieved by history

12 (EPA, 2010) are used to calculate theDocumentation for the Project condition

Require the project-specific MRV planmatching

necessary,amount of CO2 that is reported as

be developed by a professional [ACR

updating the numerical models usedsequestered and accounts for quantity of

5.4.2].

to characterize the geological storage.

CO2 in emissions, the produced gas, theThe numerical models will be adjusted

quantity remaining in the oil and gas, andtofinally the total quantity sequesteredequations

⚫

to

the

methods

quantify

and⚫

Determine

project

betweenandand,address

boundaries

where

significant

observedanddeviations⚫

Subpart RR requires the same as onDocumentation

requirements

the left.

emission offset project

predicted

behavior

References1.

Congressional Research Service (CRS). Carbon Storage Requirements in the 45Q Tax Credit. (2021).

2.

Gupta, N. & Cumming, L. United Mexican States MX TF Carbon Capture, Utilization and Storage Development in Mexico: Combining CO 2 Enhanced Oil Recovery with Permanent Storage in Mexico. 89 (2016).

3.

American Carbon Registry. Methodology for the quantification, monitoring, reporting and verification of greenhouse gas emissions reductions and removal from carbon capture and storage projects. Version 1.1. 1–75 (2021).

4.

UNFCCC, FCCC/KP/CMP/2011/10/Add.2, Decision 10/CMP.7, Modalities and procedures for carbon dioxide capture and storage in geological formations as clean development mechanism project activities (2011).

5.

Environmental Protection Agency. 40 CFR Part 146 Underground Injection Control Program: Criteria and Standards. https://www.ecfr.gov/current/title-40/chapter-I/subchapter-D/part-146?toc=1 (2022).

6.

Environmental Protection Agency. 40 CFR Part 98 Subpart RR Geologic Sequestration of Carbon Dioxide. https://www.ecfr.gov/current/title-40/chapter-I/subchapter-C/part-98?toc=1 (2022).

7.

Alberta Energy. Quantification Protocol for Enhanced Oil Recovery. Version 2.0. (2022).

8.

Alberta. Alberta Energy. Summary Report of the Regulatory Framework Assessment. 36th Annual International Pittsburgh Coal Conference: Clean Coal-Based Energy/Fuels and the Environment, PCC 2019 (2012).

1.

Congressional Research Service (CRS). Carbon Storage Requirements in the 45Q Tax Credit. (2021).

2.

Gupta, N. & Cumming, L. United Mexican States MX TF Carbon Capture, Utilization and Storage Development in Mexico: Combining CO2 Enhanced Oil Recovery with Permanent Storage in Mexico. 89 (2016).

3.

American Carbon Registry. Methodology for the quantification, monitoring, reporting and verification of greenhouse gas emissions reductions and removal from carbon capture and storage projects. Version 1.1. 1–75 (2021).

4.

UNFCCC, FCCC/KP/CMP/2011/10/Add.2, Decision 10/CMP.7, Modalities and procedures for carbon dioxide capture and storage in geological formations as clean development mechanism project activities (2011).

5.

Environmental Protection Agency. 40 CFR Part 146 Underground Injection Control Program: Criteria and Standards. https://www.ecfr.gov/current/title-40/chapter-I/subchapter-D/part-146?toc=1 (2022).

6.

Environmental Protection Agency. 40 CFR Part 98 Subpart RR Geologic Sequestration of Carbon Dioxide. https://www.ecfr.gov/current/title-40/chapter-I/subchapter-C/part-98?toc=1 (2022).

7.

Alberta Energy. Quantification Protocol for Enhanced Oil Recovery. Version 2.0. (2022).

8.

Alberta. Alberta Energy. Summary Report of the Regulatory Framework Assessment. 36th Annual International Pittsburgh Coal Conference: Clean Coal-Based Energy/Fuels and the Environment, PCC 2019 (2012).

29

for

the