This comment letter response contains two parts:   

(1) The original submittal from the commenter.

(2) A data base printout of EPA’s response to each point raised by the commenter.

Notes about the response letters:

• The response letters were generated by a data base used to track the content of all public

comment submittals and ensure that the Agency responds to each. Each comment letter

was assigned a Letter ID that corresponds to the last four digits of the docket number of the

original comment (as posted on www.regulations.gov).

• Each response letter includes: comment text; an EPA‐assigned comment code; and an

individual response. These are described and explained below.  

• The data base contains Comment text from the letters submitted by commenters.  

Many hard copy letters were scanned into electronic format for inclusion in the data

base. As a result, there may be some typographical errors attributable to optical

character recognition issues.  However, all original submittals were reviewed in the

process of drafting responses to ensure that the comment content was understood and

appropriately addressed.

• The content of each comment letter was divided into topic areas and assigned a unique

Comment ID.  Additionally, one or more Comment Codes (i.e., unique topic area ID) was

assigned to each discrete point raised by a commenter. This information was added to

the data base. To inform final rulemaking decisions, all comments and information

received on a given topic were reviewed by technical experts in each rule area (e.g., on

construction requirements).  

• Following decisions on the final rule requirements, Individual responses were drafted

by topic area to ensure completeness and consistency of the responses with the final

rule and other responses to similar comments.  Each discrete point made by a

commenter was given a unique response.

• Upon completion of comment responses, all information was entered into the data base.

Each letter response is a compilation of each comment and its individual response,

compiled in the order of the original comment letter.  As a result of this process, there is

repetition in the response text.  The Agency believes this approach ensures completeness

and attention to each comment letter that was submitted.   

• All comments in a topic area were reviewed, evaluated, and responded to concurrently.  

Responses on each topic area are compiled and are also available in the rulemaking docket.
Hydrogen Energy International Comments to EPA Proposed Rule 

By Mr. Matt Toner 

EOR and CO2 Storage 

EPA Public Hearing, Chicago, Illinois – September 30, 20008 

Docket ID No. EPA-HQ-OW-2008-0390 

INTRODOCUTION

• Thank you for the opportunity to speak here today. My name is Matt 

Toner and I work for Hydrogen Energy International, where I am the 

Carbon Storage Manager for North & South America. I have over 28 

years of Oil & Gas Industry experience, including management of 

CO2 EOR operations in West Texas. 

• Hydrogen Energy is a joint venture between BP Alternative Energy 

and Rio Tinto and our corporate directive is to develop low-carbon 

power utilizing pre-combustion separation of Hydrogen and Carbon 

Dioxide. Currently we have two projects undergoing regulatory 

review in Bakersfield, California, and the United Arab Emirates, as 

well as several other projects in various stages of evaluation. To 

date we are the only company in the world to have secured a fullypermitted, industrial-scale facility of this type. 

• As such, we are deeply appreciative of EPA's efforts to create a 

regulatory process to facilitate the capture and storage of CO2, while 

protecting Underground Sources of Drinking Water and the health 

and safety of the public. 

EOR RECOGNITION

• EPA has recognized the valuable role that oil and gas reservoirs can 

play in the geologic storage of CO2, and Hydrogen Energy would 

encourage that EPA go significantly further in facilitating use of these 

reservoirs. When CO2 is injected for Enhanced Oil or Gas 

Recovery, it could at the same time be sequestered for long term 

storage at the option of the operator. EPA should recognize this 

concurrent dual purpose, CO2 Injection for Enhanced Oil or Gas 

Recovery and Designed Storage, and allow this dual purpose under 

existing Class II UIC rules. Furthermore, EPA regulations should 
Hydrogen Energy International Comments to EPA Proposed Rule 

By Mr. Matt Toner 

Docket ID No. EPA-HQ-OW-2008-0390 

Page 2 

facilitate grandfathering from dual purpose production and storage to 

storage-only sites when EOR/EGR operations are completed. 

• In the course of a typical EOR operation, even where there is no 

intent to sequester, 30-50% on the injected CO2 remains in the 

reservoir after production operations cease. The balance is either 

miscibly dissolved within the produced oil or recycled for use in other 

reservoirs — it is not emitted to the atmosphere. Today ~90% of the 

CO2 used in enhanced recovery operations is produced from 

naturally occurring accumulations. Rather than using this naturally 

occurring CO2, society can mitigate greenhouse gas emissions by 

using anthropogenic sources. In addition, injection can continue 

upon the completion of production operations, to fully utilize all 

existing pore space - What we call EOR + Storage. 

• Oil and Gas reservoirs have proven capable of containing waterbuoyant fluids and gases for millions of years. These reservoirs are 

well studied and they offer the best opportunity to kick-start largescale geologic storage of CO2 - building on 100 years of oil field 

operating experience and adding insights which can be applied to 

saline storage. 

• EPA recognition of anthropogenic EOR + storage as a valid method 

of geologic sequestration, subject of course to appropriate 

measurement, monitoring and site closure, will provide much needed 

economic incentive to near-term Carbon Capture and Storage 

efforts, while longer-term Cap & Trade or Taxation schemes 

develop, in support of saline storage options. 

STREAMLINING OF REQUIREMENTS 

• Existing Class II regulations governing injection of CO2 in oil & gas 

reservoirs have proven successful at protecting USDWs and the 

health and safety of the public at large. These regulations should 

allow for the dual purpose of sequestration, if anthropogenic CO2 is 

used. 

• Hydrogen Energy also recommends that EPA expand grandfathering 

to facilitate transition from production and storage to storage-only 
Hydrogen Energy International Comments to EPA Proposed Rule 

By Mr. Matt Toner 

Docket ID No. EPA-HQ-OW-2008-0390 

Page 3 

sites, which will incentivize the use of these reservoirs for long-term 

CO2 storage. 

• Proposed grandfathering of Class II wells should go beyond just 

construction requirements to include, at a minimum, operating and 

mechanical integrity requirements for existing, operationally 

compliant, Class II EOR-CO2 injection wells. The Class VI 

requirements would require technically unnecessary changes to 

equipment and monitoring procedures. 

• Some authors have identified leakage risk with using oil & gas 

reservoirs for CO2 sequestration due to the presence of inactive 

wells. Proper plugging and abandonment of inactive wells is a 

proven method which can ensure this risk is effectively managed. In 

addition, the oil and gas industry has developed techniques to 

quickly isolate, effectively repair and remediate these issues, in their 

unlikely occurrence. 

CONCLUSION

• In closing, Hydrogen Energy would like to applaud EPA for their 

effort to create an effective regulatory framework for the 

sequestration of Carbon Dioxide while protecting USDW's. However, 

we believes that EPA should go significantly further than the 

proposed regulation, by recognizing the potential for concurrent, 

CO2 Injection for Enhanced Oil or Gas Recovery and Designed 

Storage and allowing for this dual purpose. Furthermore, EPA should 

facilitate grandfathering from dual purpose production and storage to 

storage-only sites when EOR/EGR operations are completed. 

• Incentivizing the use of anthropogenic CO2 for enhanced oil or gas 

recovery would: 

– Significantly reduce CO2 emissions - Currently over 2 billion 

cubic feet of naturally-occurring CO2 is used for EOR in the 

US every day and volumes are growing; 

– Increase Energy security by facilitating additional EOR activity 

and thereby reducing the need for foreign oil - EOR has the 

potential to add 40-80 billion barrels of oil, based on DOE 
Hydrogen Energy International Comments to EPA Proposed Rule 

By Mr. Matt Toner 

Docket ID No. EPA-HQ-OW-2008-0390 

Page 4 

estimates, which is 2 to 4 times the current US total proved 

reserves; 

– Effectively utilize proven, well-studied and well-tested 

geologic storage containers - It will likely cost $10's of millions 

and take years of study to permit one commercial scale saline 

storage reservoir; 

– Effectively utilize over 100 years of oil field operating 

experience while building new competence for future saline 

storage options; 

– Effectively build on the successful regulatory framework for 

UIC Class II wells; 

– and, finally, it would help kick-start the financially challenged 

carbon capture industry, by improving economics and 

accelerating uptake of this critical technology. 

Thank You. 

 
Letter ID: 0117 

Commenter: Matt Toner 

Organization: Hydrogen Energy International 

Letter ID: 0117 Comment ID: 22058 Letter Lines: 36 to 57 

Comment Code: 2064 1.5.3.2 Grandfathering construction of Class II wells (seeking comment) 

Comment: EPA has recognized the valuable role that oil and gas reservoirs can play in the 

geologic storage of CO2, and Hydrogen Energy would encourage that EPA go 

significantly further in facilitating use of these reservoirs. When CO2 is 

injected for Enhanced Oil or Gas Recovery, it could at the same time be 

sequestered for long term storage at the option of the operator. EPA should 

recognize this concurrent dual purpose, CO2 Injection for Enhanced Oil or Gas 

Recovery and Designed Storage, and allow this dual purpose under existing Class 

II UIC rules. Furthermore, EPA regulations should Hydrogen Energy International 

Comments to EPA Proposed Rule facilitate grandfathering from dual purpose 

production and storage to storage-only sites when EOR/EGR operations are 

completed. 

In the course of a typical EOR operation, even where there is no intent to 

sequester, 30-50% on the injected CO2 remains in the reservoir after production 

operations cease. The balance is either miscibly dissolved within the produced 

oil or recycled for use in other reservoirs - it is not emitted to the 

atmosphere. Today ~90% of the CO2 used in enhanced recovery operations is 

produced from naturally occurring accumulations. Rather than using this 

naturally occurring CO2, society can mitigate greenhouse gas emissions by using 

anthropogenic sources. In addition, injection can continue upon the completion 

of production operations, to fully utilize all existing pore space - What we 

call EOR + Storage. 

Individual Response: EPA agrees that many Class II wells are designed and constructed to 

withstand exposure to CO2. The final GS rule provides for the construction of these wells to be 

grandfathered per §146.81(c), provided the owner or operator can demonstrate to the Director 

that the wells were engineered and constructed to meet the requirements at §146.86(a) and 

ensure protection of USDWs, in lieu of requirements at §146.86(b) and §146.87(a). EPA clarifies 

that only the construction requirements are grandfathered and that all other Class VI 

requirements (reporting, monitoring, mechnical integrity testing, etc.) must be met following a 

determination under §146.81(c). 

Letter ID: 0117 Comment ID: 22059 Letter Lines: 59 to 69 

Comment Code: 2143 1.6.2.1 Comments in favor of injection into depleted reservoirs 

Comment: Oil and Gas reservoirs have proven capable of containing waterbuoyant fluids and 

1
gases for millions of years. These reservoirs are well studied and they offer 

the best opportunity to kick-start largescale geologic storage of CO2 - building 

on 100 years of oil field operating experience and adding insights which can be 

applied to saline storage. 

EPA recognition of anthropogenic EOR + storage as a valid method of geologic 

sequestration, subject of course to appropriate measurement, monitoring and site 

closure, will provide much needed economic incentive to near-term Carbon Capture 

and Storage efforts, while longer-term Cap & Trade or Taxation schemes develop, 

in support of saline storage options. 

Individual Response: EPA acknowledges the comment and agrees that depleted oil and gas 

fields are promising formations for GS, provided the Class VI siting, well construction and 

operation, monitoring and testing, and post-injection site care and site closure requirements are 

met under today’s final rule. EPA adds that injection of carbon dioxide for the purposes of 

enhanced oil recovery is classified as Class II injection, not Class VI, and will require a Class II 

permit. Wells for which the primary purpose is long term sequestration are considered Class VI 

wells. EPA further clarifies that the GS rule is not intended to promote a preference for GS in 

any particular formation type, to address use of resources, or to reduce costs associated with GS 

into various formations. The focus of the GS rule is to ensure that, where GS is deployed, it is 

conducted in a manner that protects USDWs from endangerment. 

Letter ID: 0117 Comment ID: 22060 Letter Lines: 65 to 69 

Comment Code: 1410 1.2.1 Comments in support of EPA/rulemaking 

Comment: EPA recognition of anthropogenic EOR + storage as a valid method of geologic 

sequestration, subject of course to appropriate measurement, monitoring and site 

closure, will provide much needed economic incentive to near-term Carbon Capture 

and Storage efforts, while longer-term Cap & Trade or Taxation schemes develop, 

in support of saline storage options. 

Individual Response: EPA recognizes that the oil and gas industry has decades of experience 

injecting CO2 for the purpose of ER, and that sites used for ER may be suitable for GS and may 

be among the first GS sites. EPA also recognizes that a by-product of ER activities is that a 

certain percentage of the CO2 is trapped in the receiving formation. 

However, EPA clarifies that injection of CO2 for the purposes of enhanced oil and gas recovery 

will continue to be permitted under the Class II program until the Director determines under 

§144.19 that the primary purpose of CO2 injection project is long term storage wherein a Class 

VI permit is required. Class VI requirements will apply to wells used for the purpose of longterm GS. The requirements for Class VI wells are tailored to address the unique nature of fullscale CO2 GS, including the volumes of CO2 being anticipated for long-term storage, the 

buoyant nature of the injectate, its mobility within subsurface geologic formations, and its 

corrosivity in the presence of water. EPA adds that the intent of the GS rule is not to promote 

2
GS; rather it is designed to ensure that, where deployed, GS is conducted in a manner that 

protects USDWs from endangerment. 

Letter ID: 0117 Comment ID: 22061 Letter Lines: 71 to 93 

Comment Code: 2046 1.5.2.3 Continuing to classify CO2 injection for EOR/EGR as Class II/ 

dividing line between Class II and Class VI (seeking comment) 

Comment Code: 2064 1.5.3.2 Grandfathering construction of Class II wells (seeking comment) 

Comment: STREAMLINING OF REQUIREMENTS 

Existing Class II regulations governing injection of CO2 in oil & gas reservoirs 

have proven successful at protecting USDWs and the health and safety of the 

public at large. These regulations should allow for the dual purpose of 

sequestration, if anthropogenic CO2 is used. 

Hydrogen Energy also recommends that EPA expand grandfathering to facilitate transition from 

production and storage to storage-only sites, which will incentivize the use of these reservoirs for 

long-term CO2 storage. 

Proposed grandfathering of Class II wells should go beyond just construction 

requirements to include, at a minimum, operating and mechanical integrity 

requirements for existing, operationally compliant, Class II EOR-CO2 injection 

wells. The Class VI requirements would require technically unnecessary changes 

to equipment and monitoring procedures. 

Some authors have identified leakage risk with using oil & gas reservoirs for 

CO2 sequestration due to the presence of inactive wells. Proper plugging and 

abandonment of inactive wells is a proven method which can ensure this risk is 

effectively managed. In addition, the oil and gas industry has developed 

techniques to quickly isolate, effectively repair and remediate these issues, in 

their unlikely occurrence. 

Individual Response: As described above, the final GS rule provides for the construction of 

Class II wells to be grandfathered per §146.81(c), provided the owner or operator can 

demonstrate to the Director that the wells were engineered and constructed to meet the 

requirements at §146.86(a) and ensure protection of USDWs, in lieu of requirements at 

§146.86(b) and §146.87(a). 

EPA disagrees that other requirements (e.g., MITs, siting, monitoring, operational, and AoR 

requirements) should also be grandfathered. Following re-permitting of the well as Class VI, 

many of the unique factors of GS sites (e.g., increased reservoir pressures associated with large 

volumes of stored CO2 and the corrosivity of CO2 in the presence of water) will result in an 

increased risk profile, warranting the specific requirements in the final GS rule. Therefore, 

following re-permitting as Class VI wells, these projects must be subject to the operational, MIT, 

monitoring, reporting, plugging, and post-injection site care and site closure requirements in the 

3
final GS rule. See the discussion of EPA's final regulatory approach in the preamble to the GS 

rule for additional detail on these requirements. 

Letter ID: 0117 Comment ID: 22062 Letter Lines: 97 to 104 

Comment Code: 2044 1.5.2.2 Oppose Class VI/ Support Class II 

Comment Code: 2064 1.5.3.2 Grandfathering construction of Class II wells (seeking comment) 

Comment: In closing, Hydrogen Energy would like to applaud EPA for their effort to create 

an effective regulatory framework for the sequestration of Carbon Dioxide while 

protecting USDW's. However, we believes that EPA should go significantly further 

than the proposed regulation, by recognizing the potential for concurrent, CO2 

Injection for Enhanced Oil or Gas Recovery and Designed Storage and allowing for 

this dual purpose. Furthermore, EPA should facilitate grandfathering from dual 

purpose production and storage to storage-only sites when EOR/EGR operations are 

completed. 

Individual Response: EPA clarifies that injection for enhanced recovery is permitted under 

Class II. EPA disagrees that dual purpose underground injection should be authorized under the 

UIC program because the unique risks posed by long term storage of CO2 for GS cannot be 

addressed under existing UIC requirements, such as those for Class II wells. EPA believes that 

there are significant differences between how projects are operated, as well as the risks posed by 

these different injection activities. The new tailored approach of the GS rule was designed to 

address the general risks deep injection may pose to USDWs and was tailored specifically to 

address the risks posed by long term storage of CO2 (i.e., very large volumes, very long timeperiods, and reservoir pressure conditions). 

EPA notes that many Class II wells are designed and constructed to withstand exposure to CO2. 

The final Class VI regulations require that any owner or operator injecting CO2 for the primary 

purpose of long term storage obtain a Class VI permit with some special consideration for the 

fact that they are transitioning from a well not originally designed to meet Class VI requirements. 

The Director has the authority to determine at what point a Class VI permit is required for those 

projects that are transitioning from the primary purpose of EOR to long term storage of CO2. 

The final regulation provides a set of technical factors for the Director to evaluate in making this 

determination, at §144.19. EPA believes that this approach provides sufficient protection of 

USDWs when there is an increased risk to USDWs as compared to traditional Class II operations 

while allowing for site-specific flexibility. For more information, please see the discussion on 

transition of Class II wells in the preamble to the final GS rule. 

Letter ID: 0117 Comment ID: 22063 Letter Lines: 106 to 129 

Comment Code: 2046 1.5.2.3 Continuing to classify CO2 injection for EOR/EGR as Class II/ 

dividing line between Class II and Class VI (seeking comment) 

Comment: Incentivizing the use of anthropogenic CO2 for enhanced oil or gas recovery 

4
5

would: 

-Significantly reduce CO2 emissions - Currently over 2 billion cubic feet of 

naturally-occurring CO2 is used for EOR in the US every day and volumes are 

growing; 

-Increase Energy security by facilitating additional EOR activity and thereby 

reducing the need for foreign oil 

-EOR has the potential to add 40-80 billion barrels of oil, based on estimates, which is 2 to 4 

times the current US total proved reserves; 

-Effectively utilize proven, well-studied and well-tested geologic storage 

containers - It will likely cost $10's of millions and take years of study to 

permit one commercial scale saline storage reservoir; 

-Effectively utilize over 100 years of oil field operating experience while 

building new competence for future saline storage options; 

-Effectively build on the successful regulatory framework for UIC Class II wells; 

and, finally, it would help kick-start the financially challenged carbon capture 

industry, by improving economics and accelerating uptake of this critical 

technology. 

Individual Response: EPA clarifies that the purpose of the GS rule is not to incentivize or 

encourage the use of GS, but to ensure that, where GS is deployed, it is conducted in a manner 

that does not endanger USDWs. Furthermore, the purpose of the GS rule is not to incentivize the 

use of anthropogenic CO2 for EOR purposes.