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.
October 15, 2009

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

FROM: Barbara Priest, UIC Program Coordinator

Oregon Department of Environmental Quality – Water Quality Division

811 SW Sixth Avenue, Portland, Oregon 97204

SUBJECT: Comments on Federal Requirements Under the Underground Injection Control (UIC) 

Program for Carbon Dioxide (CO2) Geologic Sequestration (GS) Wells; Notice of Data 

Availability and Request for Comment

Thank you for the opportunity to respond to the proposed UIC requirements for the Geologic 

Sequestration (GS) of Carbon Dioxide as Class VI systems based on the notice of new data 

published in the Federal Register on August 31, 2009. The Oregon Department of 

Environmental Quality (DEQ) is providing comments on the proposed regulations based on 

consultation with the Oregon Department of Geology and Mineral Industries, Oregon 

Department of Water Resources and the Oregon Department of Human Services Drinking 

Water Program. 

DOE-Sponsored Regional Carbon Sequestration Partnership Projects (III.B.)

DEQ supports the pilot project approach that EPA has taken in partnership with the Department 

of Energy. A thorough site characterization is the most important requirement for most geologic 

sequestration projects. DEQ also supports the testing and research of analytical models to 

ensure protection of drinking water resources. 

Lawrence Berkeley National Laboratory (LBNL) Studies (III.C.)

The LBNL is currently evaluating potential effects of CO2 injection on ground water and 

surrounding formations, including a case study in a sedimentary basin. We have concern that 

this study does not address other types of basins which may be proposed for geologic 

sequestration in Oregon. DEQ recommends that additional studies be pursued in different 

basin scenarios on mobilization of constituents and likelihood or frequency of leakage risks. 

Risks

There are significant risks to GS. We note that GS is not the same as Enhanced Oil Recovery 

(EOR) or Enhanced Gas Recovery (EGR). GS needs to have higher standards than EOR 

activities have had to date for the following reasons:

 GS is being considered in basins without proven oil and gas capture and holding 

reservoirs. 

 Oil and gas reservoirs are being considered for geologic sequestration even where 

exhausted, and the amount of carbon dioxide to be injected is greater than used for 

EOR/EGR and the goals of the injection are different. 
Page 2 of 6

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

 There is an unknown level of risk associated with large geologic sequestration projects. 

Regulations must set high standards for site selection, site characterization and ongoing 

monitoring. 

 The proposed rules and new data also do not adequately address other types of 

hazards, such as those associated with hydro fracing and impacts to existing faults. 

EOR/EGR

We suggest keeping the programs for EOR/EGR and geologic sequestration separated. 

EOR/EGR occurs in areas with oil reservoirs with little contemplation to the site's long term 

storage and C02 containment characteristics. Long term GS CO2 storage should be based upon 

local site characterization work that verifies the reservoir provides the storage requirements with 

minimal environmental risks. 

EPA acknowledges that there are differences between Class II and VI operations that warrant 

different treatment such as risk profiles, formation pressures, CO2 volumes, more opportunities 

for mobilization, injection rates and operating conditions. 

Injection Depth for GS Projects (IV)

We believe GS should only be allowed beneath the lowest Underground Source of Drinking 

Water (USDW). Protecting USDW is the most important aspect of the UIC program and of great 

importance for the regional state economy and sustainability. Verifiable containment or a cap 

rock is critical to prevent the migration of C02 upward into USDWs. Allowing the EPA Director or 

states with delegated UIC programs to require additional confining zones is important to protect 

USDWs, especially in geologically marginal areas where GS may occur. 

Waiver Process (IV.D.)

EPA is considering an alternative through a waiver process to allow GS injection above and 

between USDWs under specific conditions that would provide flexibility and allow for more sitespecific assessment. We do not support the waiver process allowing injection above and 

between USDWs and alternatives that will undermine long term protection of USDWs for the 

following reasons: 

 The waiver process is a divergence from Class I and III requirements and would allow 

for modifications and widespread use. 

 GS in Oregon could be proposed in Columbia River Flood basalts not in saline basins, or 

deep buried volcanic plains. Oregon currently has no exempt aquifers – all aquifers 

statewide under the 1990 State Groundwater Act are considered to be protected and 

potable. 

 The waiver would place a greater burden on the state to administer this program that is 

minimally supported by current EPA funding levels that are directed towards Class I and 

II development. 
Page 3 of 6

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

Other Issues and Concerns Not Addressed With New Data

Area of Review

The proposed standards require modeling and tracking of the actual C02 plume and pressure 

front, with periodic re-evaluation of the modeled behavior as additional local experience is 

gained with a GS project. We acknowledge that modeling is a good method of predicting the 

behavior of injected C02 but should not be relied upon without monitoring to verify the accuracy 

of the modeled predictions. Modeling should be continually refined throughout the life of a 

sequestration project. 

Well Standards

We believe the proposed well construction standards may be difficult or impossible to meet in 

some geologic settings. The standards require a surface casing installed to the lowermost 

USDW and cemented to the surface. In geologic settings with bedrock and deep drinking water 

quality aquifers, it may be difficult to set the surface casings this deep. Oregon’s Columbia 

River basalts may be as deep as 10,000 feet and much of that depth with drinking water quality 

groundwater. The multiple flows and fractures in these beds make for difficult drilling and 

frequently require setting intermediate casings. The standards should allow a protective casing 

program that can be reliably installed in all geologic settings. Deep aquifers may provide the 

most protective geologic settings for C02 injection and the well construction standards should 

not discourage their use. 

Down hole valves and other required down hole equipment may impact or prevent certain 

monitoring techniques. It is important to require appropriate safeguards but leave some flexibility 

to use new technologies as new methods are developed. 

Monitoring

Direct monitoring of the formations immediately above the confining layer for a geologic 

sequestration injection zone is an important requirement for the early detection of unacceptable 

leakage or venting. The intent is to have no leakage or venting occur. Monitoring wells installed 

into these formations should be required for all projects. Geophysical methods and other 

indirect monitoring, while useful, should not be allowed to substitute for all direct monitoring 

above the confining layer. 

The number of wells drilled through the confining layer into the injection zone should be 

minimized as each new well represents a risk of establishing a pathway for the migration of C02 

or in-situ fluids into shallower aquifers. Projects may be able to get sufficient monitoring data 

from injection wells to minimize the need for stand-alone injection zone monitoring wells. 

Decisions on the level of direct and indirect monitoring should be made on a site-by-site basis, 

based upon the geologic characteristics. Some direct monitoring must be required above the 

confining layer to confirm that indirect monitoring is accurate. 

Periodic corrosion and well integrity testing is important for all pollution prevention programs. 

This well testing will help operators to focus maintenance and repair activities on the wells that 
Page 4 of 6

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

are degrading. It is better to prevent leakage from a well breach than to fix the well after 

discovering that it has leaked. We support adoption of requiring extensive corrosion controls 

with monitoring until more data is available on how cement will react long term with CO2. 

Remedial Action

Triggers should be established for when remedial action is required. The new regulations should 

address this during the permitting process so the operator and regulatory agency know what 

action is expected before impacts are observed. Everyone will then understand what the 

threshold is and will help to prevent legal efforts intended to delay the initiation of remedial 

actions when environmental impacts have been observed. 

Financial Assurance

Financial assurance accounts funded with real assets must be required as with other 

environmental programs (e.g., RCRA). Financial tests and self insurance are of no value if a 

company becomes financially insolvent. Financial assurance is only of value if the assets 

remain in the account after a company's financial demise. 

Non-C02 Contaminants

The proposed standard would allow co-disposal of imported non-C02 waste streams and nonC02 contaminants to be injected with the C02 unless the contaminants would make the C02 a 

hazardous waste. Injected gases may not qualify as a hazardous waste under current federal 

standards. It appears that the proposed rules would allow a facility to import waste materials to 

add to the C02 and be injected as a cheap disposal option and we believe this should not be 

allowed to happen. Oregon administrative rules would prohibit the injection non-C02

contaminants if technology is available for their removal. Current state rules also prohibit the 

use of underground injection for most waste disposal. An alternative option would be to allow 

non-C02 contaminants only as specifically addressed in a facility's permit and a statement that 

the non-C02 contaminants must be by-products of the C02 stream and may not be imported for 

disposal by injection with the C02. States should be able to adopt rules that are more restrictive 

related to this issue. 

Rules Subpart H Criteria and Standards (CFR 146)

146.82 (b) Required permit Information

DEQ suggests a modification to this section stating “the map will also show faults”. Section 

146.82(b) requires a map showing the injection wells and the applicable area of review, while 

section 146.82 (c) to (d) describes “data obtained during logging and testing of the well 

formation”. The last sentence in 146.82(b) should perhaps only state that information of public 

record is required to be included on this map [section 146.82 (b)], and then note that the 

requirements for maps and geological systems information in 146. 82 (c) to (d) are different. 

Derived data and supplemental data should also be discussed in association with the site 

assessment. 

146.84(a) Area of review and corrective action
Page 5 of 6

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

This section states ”that the area of review is based, in part, on computational modeling.” We

would like to know how many types of modeling exist and what the industrial standards or 

guidance is for the models. Relying on a computer model without detailed geological data is not 

adequate.

146.86(b) (3) Well construction

We interpret this regulation to imply that wells can be grouted with cement in one or more 

stages. The problem with cementing in stages is that it is possible to have cold joints that may 

allow the movement of water or other fluids within the annual space. We would prefer that the 

grout be placed in one continuous operation without a significant interruption. By that we mean 

that the grout should not be allowed to set up to a point that a cold joint would be created when 

continuing to place grout after an interruption of over 72 hours if Portland Cement is used, 48 

hours if High Early Strength Type III Portland Cement is used, or 6 hours if high Alumina 

Cement is used. Other interruption times would vary depending upon the final set time of the 

proposed grout. We also suggest it be required for continuous cementing to take a minimum 

amount of grout to complete the seal. For example, the rules should require that a minimum of 

120% to 130% of the estimated volume of sealing material be used when sealing. While this 

would not guarantee an adequate seal, the chances of a sufficient seal would be greater with 

the appropriate amount of grout. Too little grout raises a red flag. 

146.87(b) Logging, sampling, and testing prior to operation

This regulation states that the Director may accept cores from nearby wells if the 

owner/operator can demonstrate that core retrieval is not possible and that such cores are 

representative of conditions of the well. We believe that cores from nearby wells may not be 

indicative of the conditions at the well being constructed and thus if possible a down hole video 

should be made to accurately show the conditions at the well site. 

146.89 Mechanical integrity

The term “significant’’ is often used when describing leaks. We propose there should either be 

a definition of significant or the wells should be adequately sealed so there are no leaks. 

146.92 Well plugging

The proposed rules describe plugs as a way to abandon Class VI wells. Class VI wells should 

be properly abandoned to prevent a health or environmental hazard by completely filling them 

from the bottom up to the land surface with an approved sealant (e.g., cement) to ensure these 

wells do not become a health hazard or environmental concern. This assumes the well was 

properly constructed in the first place and not grandfathered in as is proposed. We suggest that 

if a well is found that is not properly constructed then another form of plugging may be 

necessary to protect the groundwater resource. 
Page 6 of 6

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

146.93 Post injection site care and closure

We suggest that post injection site care and closure data be required to be posted on-line. This 

does not address site reclamation beyond re-vegetating the pad, which currently is regulated in 

Oregon. 

c: Dr. Vicki McConnell, DOGAMI

Donn Miller, WRD

Tom Pattee, OHD-DW

Rod Weick, DEQ
Letter ID: 0366  

Commenter: Barbara Priest  

Organization: Oregon Department of Environmental Quality (DEQ)  

Letter ID: 0366 Comment ID: 27907 Letter Lines: 37 to 43  

Comment Code: 2100 2.1 DOE Regional Carbon Sequestration Partnership Projects  

Comment: DOE‐Sponsored Regional Carbon Sequestration Partnership Projects (III.B.)  

DEQ supports the pilot project approach that EPA has taken in partnership with  

the Department of Energy. A thorough site characterization is the most  

important requirement for most geologic sequestration projects. DEQ also  

supports the testing and research of analytical models to ensure protection of  

drinking water resources.  

Individual Response: EPA agrees that the pilot project approach will greatly enhance the knowledge of

site characterization and modeling needed for proper design and operation of GS projects.  

Data and information collected during site characterization also informs the development of

construction and operating plans, provides inputs for AoR delineation models, and establishes baseline

information to which geochemical, geophysical, and hydrogeologic site monitoring data collected over

the life of the injection project can be compared.  

Letter ID: 0366 Comment ID: 27908 Letter Lines: 45 to 52  

Comment Code: 2200 2.2. LBNL Studies  

Comment: Lawrence Berkeley National Laboratory (LBNL) Studies (III.C.)  

The LBNL is currently evaluating potential effects of CO2 injection on ground  

water and surrounding formations, including a case study in a sedimentary basin.  

We have concern that this study does not address other types of basins which may  

be proposed for geologic sequestration in Oregon. DEQ recommends that  

additional studies be pursued in different basin scenarios on mobilization of  

constituents and likelihood or frequency of leakage risks.  

Individual Response: EPA continues to monitor the progress of research on the feasibility of various
types of geologic formations. For example, DOE's RCSPs are conducting numerous pilot projects that

inject CO2 into a variety of formation types, including saline, basalt, coal seams, and oil and gas

reservoirs. EPA is using an adaptive approach to regulate GS injection. EPA will collect and review project

data on early GS projects, including those that inject into formations such as coal seams and basalts, to

determine whether the appropriate amount and types of information and documentation are required

and being collected. EPA plans, every six years, to collect and review data on GS projects to determine

whether the appropriate amount and types of information and appropriate documentation are being

collected, and to determine if modifications to the requirements are appropriate or necessary.  

Letter ID: 0366 Comment ID: 27909 Letter Lines: 54 to 65  

Comment Code: 3130 3.1.3. Addressing the Differences Between Class II and Class VI Wells  

Comment: Risks  

There are significant risks to GS. We note that GS is not the same as Enhanced  

Oil Recovery (EOR) or Enhanced Gas Recovery (EGR). GS needs to have  

higher standards than EOR activities have had to date for the following reasons:  

‐ GS is being considered in basins without proven oil and gas capture and  

holding reservoirs.  

‐ Oil and gas reservoirs are being considered for geologic sequestration even  

where exhausted, and the amount of carbon dioxide to be injected is greater than  

used for EOR/EGR and the goals of the injection are different.  

Individual Response: EPA agrees that ER is different than GS, and clarifies that the final GS rule

requirements are designed to address these unique attributes of GS.  

Letter ID: 0366 Comment ID: 27910 Letter Lines: 75 to 87  

Comment Code: 5700 5.14. Comments on Other Aspects of the Proposed Rule  

Comment: EOR/EGR  

We suggest keeping the programs for EOR/EGR and geologic sequestration  

separated. EOR/EGR occurs in areas with oil reservoirs with little contemplation  

to the site's long term storage and CO2 containment characteristics. Long term GS  

CO2 storage should be based upon local site characterization work that verifies  
the reservoir provides the storage requirements with minimal environmental  

risks.  

EPA acknowledges that there are differences between Class II and VI operations  

that warrant different treatment such as risk profiles, formation pressures, CO2  

volumes, more opportunities for mobilization, injection rates and operating  

conditions.  

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is outside the

scope of the Notice of Data Availability. Please see responses to comments on the proposed rule for

EPA’s response to similar comments.  

Letter ID: 0366 Comment ID: 27911 Letter Lines: 89 to 117  

Comment Code: 3220 3.2.2. Comments in Opposition to the Approach  

Comment: Injection Depth for GS Projects (IV)  

We believe GS should only be allowed beneath the lowest Underground Source of  

Drinking Water (USDW). Protecting USDW is the most important aspect of the UIC  

program and of great importance for the regional state economy and  

sustainability. Verifiable containment or a cap rock is critical to prevent the  

migration of CO2 upward into USDWs. Allowing the EPA Director or states with  

delegated UIC programs to require additional confining zones is important to  

protect USDWs, especially in geologically marginal areas where GS may occur.  

Waiver Process (IV.D.)  

EPA is considering an alternative through a waiver process to allow GS injection  

above and between USDWs under specific conditions that would provide  

flexibility and allow for more site‐ specific assessment. We do not support the  

waiver process allowing injection above and between USDWs and alternatives that  

will undermine long term protection of USDWs for the following reasons:  

‐ The waiver process is a divergence from Class I and III requirements and would  

allow for modifications and widespread use.  

‐ GS in Oregon could be proposed in Columbia River Flood basalts not in saline  

basins, or deep buried volcanic plains. Oregon currently has no exempt aquifers  

‐ all aquifers statewide under the 1990 State Groundwater Act are considered to  
be protected and potable.  

‐ The waiver would place a greater burden on the state to administer this  

program that is minimally supported by current EPA funding levels that are  

directed towards Class I and II development.  

Individual Response: EPA agrees that USDW protection is the highest priority and clarifies that the

purpose of the GS regulation is to ensure that GS, where deployed, is conducted in a manner that

protects USDWs. Incentivizing the use of GS or other renewable energy resources and technologies is

outside the scope of this rulemaking and the UIC Program’s authority under the SDWA. EPA disagrees

that finalization of the GS rule is premature. For additional information regarding the data on which EPA

based the final GS rule, see the preamble to the final GS rule.

EPA acknowledges the commenter's concerns about USDW protection and clarifies that the mission of

the UIC Program is to protect USDWs from endangerment. Based on an evaluation of comments on the

proposed injection depth requirements, the waiver process discussed in the NODA and Request for

Comment, and concerns about USDW protection, EPA believes that there are situations where injection

into non‐USDW formations above the lowermost USDW can be performed in a manner that protects

USDWs. The final GS rule at §146.95 establishes a process by which owners or operators can seek a

waiver of the Class VI injection depth requirements. The waiver approach establishes requirements for

extensive site‐specific information related to injecting above or between USDWs that the owner or

operator must submit and the Director must consider, in consultation with PWSS Directors, to ensure

that water supplies in the area and all USDWs are protected.  

Furthermore, owners or operators granted injection depth waivers are subject to additional

requirements at §146.95(f), which include modified construction requirements and requirements to

monitor above and below the injection zone in order to ensure protection of USDWs underlying and

overlying the injection zone during both well operation and the post‐injection site care period.  

EPA clarifies that adoption of the waiver process remains at the discretion of individual UIC programs.

Therefore, States, Territories, and Tribes seeking primacy for Class VI wells are not required to provide

for injection depth waivers in their UIC regulations and may choose not to make this process available to

Class VI wells under their jurisdiction. This approach allows flexibility for individual program Directors to

determine the appropriateness of allowing for waivers based on regional or state‐specific conditions,

such as the predominant geologic settings anticipated to be used for GS or other land uses in the state

while ensuring maximum protection of USDWs. The final approach for injection depth waivers

represents minimum Federal requirements. UIC program Directors may adopt GS requirements that do

not allow injection above or between USDWs if they determine this to be appropriate (for conditions in

their State, territory, Tribe, or Region) and protective.  
Letter ID: 0366 Comment ID: 27912 Letter Lines: 122 to 130  

Comment Code: 5150 5.3. Comments on the Proposed AoR and Corrective Action Requirements

(146.84)  

Comment: Area of Review  

The proposed standards require modeling and tracking of the actual CO2 plume and  

pressure front, with periodic re‐evaluation of the modeled behavior as  

additional local experience is gained with a GS project. We acknowledge that  

modeling is a good method of predicting the behavior of injected CO2 but should  

not be relied upon without monitoring to verify the accuracy of the modeled  

predictions. Modeling should be continually refined throughout the life of a  

sequestration project.  

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is outside the

scope of the Notice of Data Availability. Please see responses to comments on the proposed rule for

EPA’s response to similar comments.  

Letter ID: 0366 Comment ID: 27913 Letter Lines: 132 to 149  

Comment Code: 5250 5.5. Comments on the Proposed Construction Requirements (146.86)  

Comment: Well Standards  

We believe the proposed well construction standards may be difficult or  

impossible to meet in some geologic settings. The standards require a surface  

casing installed to the lowermost USDW and cemented to the surface. In geologic  

settings with bedrock and deep drinking water quality aquifers, it may be  

difficult to set the surface casings this deep. Oregon's Columbia River basalts  

may be as deep as 10,000 feet and much of that depth with drinking water quality  

groundwater. The multiple flows and fractures in these beds make for difficult  

drilling and frequently require setting intermediate casings. The standards  

should allow a protective casing program that can be reliably installed in all  

geologic settings. Deep aquifers may provide the most protective geologic  

settings for CO2 injection and the well construction standards should not discourage  

their use.  

Down hole valves and other required downhole equipment may impact or prevent  

certain monitoring techniques. It is important to require appropriate safeguards  
but leave some flexibility to use new technologies as new methods are developed.  

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is outside the

scope of the Notice of Data Availability. Please see responses to comments on the proposed rule for

EPA’s response to similar comments.  

Letter ID: 0366 Comment ID: 27914 Letter Lines: 151 to 178  

Comment Code: 5450 5.9. Comments on the Proposed Monitoring Requirements (146.90)  

Comment: Monitoring  

Direct monitoring of the formations immediately above the confining layer for a  

geologic sequestration injection zone is an important requirement for the early  

detection of unacceptable leakage or venting. The intent is to have no leakage  

or venting occur. Monitoring wells installed into these formations should be  

required for all projects. Geophysical methods and other indirect monitoring,  

while useful, should not be allowed to substitute for all direct monitoring  

above the confining layer.  

The number of wells drilled through the confining layer into the injection zone  

should be minimized as each new well represents a risk of establishing a pathway  

for the migration of C02 or in‐situ fluids into shallower aquifers. Projects may  

be able to get sufficient monitoring data from injection wells to minimize the  

need for stand‐alone injection zone monitoring wells.  

Decisions on the level of direct and indirect monitoring should be made on a  

site‐by‐site basis, based upon the geologic characteristics. Some direct  

monitoring must be required above the confining layer to confirm that indirect  

monitoring is accurate.  

Periodic corrosion and well integrity testing is important for all pollution  

prevention programs. This well testing will help operators to focus maintenance  

and repair activities on the wells that are degrading. It is better to prevent  

leakage from a well breach than to fix the well after discovering that it has  

leaked. We support adoption of requiring extensive corrosion controls with  

monitoring until more data is available on how cement will react long term with  

CO2.  

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is outside the
scope of the Notice of Data Availability. Please see responses to comments on the proposed rule for

EPA’s response to similar comments.  

Letter ID: 0366 Comment ID: 27915 Letter Lines: 180 to 187  

Comment Code: 5650 5.13. Comments on the Proposed Emergency and Remedial Response

Requirements (146.94)  

Comment: Remedial Action  

Triggers should be established for when remedial action is required. The new  

regulations should address this during the permitting process so the operator and  

regulatory agency know what action is expected before impacts are observed.  

Everyone will then understand what the threshold is and will help to prevent legal  

efforts intended to delay the initiation of remedial actions when environmental  

impacts have been observed.  

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is outside the

scope of the Notice of Data Availability. Please see responses to comments on the proposed rule for

EPA’s response to similar comments.  

Letter ID: 0366 Comment ID: 27916 Letter Lines: 189 to 195  

Comment Code: 5200 5.4. Comments on the Proposed Financial Responsibility Requirements (146.85)  

Comment: Financial Assurance  

Financial assurance accounts funded with real assets must be required as with  

other environmental programs (e.g., RCRA). Financial tests and self insurance  

are of no value if a company becomes financially insolvent. Financial assurance  

is only of value if the assets remain in the account after a company's financial  

demise.  

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is outside the

scope of the Notice of Data Availability. Please see responses to comments on the proposed rule for

EPA’s response to similar comments.  
Letter ID: 0366 Comment ID: 27917 Letter Lines: 197 to 212  

Comment Code: 5700 5.14. Comments on Other Aspects of the Proposed Rule  

Comment: Non‐CO2 Contaminants  

The proposed standard would allow co‐disposal of imported non‐C02 waste  

streams and non‐CO2 contaminants to be injected with the C02unless the  

contaminants would make the CO2 a hazardous waste. Injected gases may not  

qualify as a hazardous waste under current federal standards. It appears that  

the proposed rules would allow a facility to import waste materials to add to  

the CO2 and be injected as a cheap disposal option and we believe this should not  

be allowed to happen. Oregon administrative rules would prohibit the injection  

non‐CO2 contaminants if technology is available for their removal. Current state  

rules also prohibit the use of underground injection for most waste disposal. An  

alternative option would be to allow non‐CO2 contaminants only as specifically  

addressed in a facility's permit and a statement that the non‐C02 contaminants  

must be by‐products of the CO2 stream and may not be imported for disposal by  

injection with the CO2. States should be able to adopt rules that are more  

restrictive related to this issue.  

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is outside the

scope of the Notice of Data Availability. Please see responses to comments on the proposed rule for

EPA’s response to similar comments.  

Letter ID: 0366 Comment ID: 27918 Letter Lines: 214 to 226  

Comment Code: 5050 5.1. Comments on the Proposed Permit Application Information (146.82)  

Comment: Rules Subpart H Criteria and Standards (CFR 146)  

146.82 (b) Required permit Information  

DEQ suggests a modification to this section stating "the map will also show  

faults". Section 146.82(b) requires a map showing the injection wells and the  

applicable area of review, while section 146.82 (c) to (d) describes "data  

obtained during logging and testing of the well formation". The last sentence  

in 146.82(b) should perhaps only state that information of public record is  

required to be included on this map [section 146.82 (b)], and then note that the  

requirements for maps and geological systems information in 146. 82 (c) to (d)  
are different. Derived data and supplemental data should also be discussed in  

association with the site assessment.  

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is outside the

scope of the Notice of Data Availability. Please see responses to comments on the proposed rule for

EPA’s response to similar comments.  

Letter ID: 0366 Comment ID: 27919 Letter Lines: 228 to 233  

Comment Code: 5150 5.3. Comments on the Proposed AoR and Corrective Action Requirements

(146.84)  

Comment: 146.84(a) Area of review and corrective action  

This section states "that the area of review is based, in part, on computational  

modeling." we would like to know how many types of modeling exist and what  

the industrial standards or guidance is for the models. Relying on a computer  

model without detailed geological data is not adequate.  

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is outside the

scope of the Notice of Data Availability. Please see responses to comments on the proposed rule for

EPA’s response to similar comments.  

Letter ID: 0366 Comment ID: 27920 Letter Lines: 235 to 252  

Comment Code: 5250 5.5. Comments on the Proposed Construction Requirements (146.86)  

Comment: 146.86(b) (3) Well construction  

We interpret this regulation to imply that wells can be grouted with cement in one  

or more stages. The problem with cementing in stages is that it is possible to  

have cold joints that may allow the movement of water or other fluids within the  

annual space. We would prefer that the grout be placed in one continuous  

operation without a significant interruption. By that we mean that the grout  

should not be allowed to set up to a point that a cold joint would be created  

when continuing to place grout after an interruption of over 72 hours if  

Portland Cement is used, 48 hours if High Early Strength Type III Portland  

Cement is used, or 6 hours if high Alumina Cement is used. Other interruption  

times would vary depending upon the final set time of the proposed grout. We also  
suggest it be required for continuous cementing to take a minimum amount of  

grout to complete the seal. For example, the rules should require that a  

minimum of 120% to 130% of the estimated volume of sealing material be used when  

sealing. While this would not guarantee an adequate seal, the chances of a  

sufficient seal would be greater with the appropriate amount of grout. Too  

little grout raises a red flag.  

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is outside the

scope of the Notice of Data Availability. Please see responses to comments on the proposed rule for

EPA’s response to similar comments.  

Letter ID: 0366 Comment ID: 27921 Letter Lines: 254 to 261  

Comment Code: 5300 5.6. Comments on the Proposed Logging, Sampling, and Testing Requirements

(146.87)  

Comment: 146.87(b) Logging, sampling, and testing prior to operation  

This regulation states that the Director may accept cores from nearby wells if the  

owner/operator can demonstrate that core retrieval is not possible and that such  

cores are representative of conditions of the well. We believe that cores from  

nearby wells may not be indicative of the conditions at the well being  

constructed and thus if possible a down hole video should be made to accurately  

show the conditions at the well site.  

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is outside the

scope of the Notice of Data Availability. Please see responses to comments on the proposed rule for

EPA’s response to similar comments.  

Letter ID: 0366 Comment ID: 27922 Letter Lines: 263 to 267  

Comment Code: 5400 5.8. Comments on the Proposed MIT Requirements (146.89)  

Comment: 146.89 Mechanical integrity  

The term "significant" is often used when describing leaks. We propose there  

should either be a definition of significant or the wells should be adequately  

sealed so there are no leaks.  
Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is outside the

scope of the Notice of Data Availability. Please see responses to comments on the proposed rule for

EPA’s response to similar comments.  

Letter ID: 0366 Comment ID: 27923 Letter Lines: 269 to 278  

Comment Code: 5550 5.11. Comments on the Proposed Well Plugging Requirements (146.92)  

Comment: 146.92 Well plugging  

The proposed rules describe plugs as a way to abandon Class VI wells. Class VI  

wells should be properly abandoned to prevent a health or environmental hazard  

by completely filling them from the bottom up to the land surface with an  

approved sealant (e.g., cement) to ensure these wells do not become a health  

hazard or environmental concern. This assumes the well was properly constructed  

in the first place and not grandfathered in as is proposed. We suggest that if a  

well is found that is not properly constructed then another form of plugging may  

be necessary to protect the groundwater resource.  

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is outside the

scope of the Notice of Data Availability. Please see responses to comments on the proposed rule for

EPA’s response to similar comments.  

Letter ID: 0366 Comment ID: 27924 Letter Lines: 280 to 284  

Comment Code: 5600 5.12. Comments on the Proposed Post‐Injection Site Care Requirements (146.93)  

Comment: 146.93 Post injection site care and closure  

We suggest that post injection site care and closure data be required to be  

posted on‐line. This does not address site reclamation beyond re‐vegetating the  

pad, which currently is regulated in Oregon.  

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is outside the

scope of the Notice of Data Availability. Please see responses to comments on the proposed rule for

EPA’s response to similar comments.  
Letter ID: 0366 Comment ID: 28563 Letter Lines: 67 to 73  

Comment Code: 3100 3.1. Comments on Concerns About Injection Depth for Class VI Wells  

Comment: ‐ There is an unknown level of risk associated with large geologic sequestration  

projects. Regulations must set high standards for site selection, site  

characterization and ongoing monitoring.  

‐ The proposed rules and new data also do not adequately address other types of  

hazards, such as those associated with hydro fracing and impacts to existing  

faults.  

Individual Response: EPA agrees that site selection, site characterization, and monitoring, along with

well construction, operation, and post‐injection site care are important to protect USDWs from

endangerment. EPA believes the final GS rule sets high standards for USDW protection that are tailored

to the unique challenges posed by GS.

For additional information on proper site characterization, pressure limits, and the use of hydraulic

fracturing at GS projects, see the preamble to the final rule and the responses to comments on the

proposed GS rule.