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.BP Alternative Energy International Limited, a company registered in England and Wales with the company number 1553681, VAT num ber GB 243 5105 93 and whose registered office is

Chertsey Road, Sunbury on Thames, Middlesex, TW16 7BP.

BP Alternative Energy Holdings Limited, a company registered in England and Wales with the company number 2515099, VAT number G B 243 5105 93 and whose registered office is

Chertsey Road, Sunbury on Thames, Middlesex, TW16 7BP BP Alternative Energy Comments to EPA Proposed Rule By Mr. Brian Williams Well Design Construction and Operations EPA Public Hearing, Chicago, Illinois – September 30, 20008

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

INTRODUCTION

 Good morning and thank you for the opport unity to speak here today. My name is

Brian Williams and I work for BP’s Alternative Energy division in Houston. There I am the global CO2 Storage Manage r in our Carbon Capture & Storage Technology organization.

 I work in a team that is developing the technological capabilities needed to deliver a capability for geologic storage for BP. One of the particular areas where we are developing technologies and where we have done specific research and field analysis relates to well construction & operational requ irements. These are the areas where I’d like to direct my comments today.

RECOGNITION OF CRITICALITY OF WELLS

 EPA has correctly recognized that wells are a fundamental component of a geologic storage system that successfully ensures the c ontainment of stored CO2. As such, we agree that having appropriate well design, construction & operating requirements are critical to the delivery of secure storage of CO2.

 Oil and gas operators have deca des of experience, via past and existing operations, in constructing and operating EOR/ EGR wells in a safe and secure way. For existing EOR projects and wells, Class II requirements have proven to be sufficient at ensuring the necessary protection of USDWs, and, th erefore, analysis of the experiences and performances of these Class II CO2 EOR we lls should inform the requirements for

new Class VI wells.

 I would like to comment on certain of the incremental requirements in the draft rule, including the preamble, around the design, construction & operation of Class VI wells that we feel are potentially excessive.

WELL CONSTRUCTION

 Corrosion resistant materials & cement – Based on industry experience and field

studies, corrosion resistant materials should not be mandated for all projects, and the requirement, if there is any, should be ma de on a site-specific ba sis. Early field studies (by the CO2 Capture Pr oject) indicate that it is the appropriate placement of cement, and not the type of cement, that delivers isolation & prevents casing

corrosion.BP Alternative Energy Comments to EPA Proposed Rule By Mr. Brian Williams

Docket ID No. EPA-HQ-OW-2008-0390 Page 2

The choice of casing and cement materi als should be selected based on planned well operating life (i.e., decades), not on the ultimate duration of the stor age program. The potential for longer term exposure of casi ng during storage, which might occur after injection has stopped, is mitigated by plugging the static well with corrosion-resistant material, if it is deemed necessary at that time.

 Cement across long string casing -- BP does not agree with t he requirement for a long string from the injection interval to su rface or with cementing across that entire

distance. Allowance should be made for a liner to be set across the injection interval when the previous string is set above that zone. Cement should cover the uppermost caprock in the Area of Review by a margin of approximately 500 feet, not to surface. The ultimate decision for each project s hould rest with the Director since each is unique in the geological intervals of the c aprock(s) and injection zone(s) and of the position relative to USDW(s). Any expecta tion to cement in the injection interval should permit the use of external casing packers in conjunction with the cementing requirements across the caprock.

WELL OPERATIONS

 No CO2 injection above lowest known USDW -- BP does not subscribe to a blanket, artificial constraint that would limit inject ion only to reservoirs below the USDW. More appropriate, given the EPA’s general performance-based approac h, would be to place containment requirements on the acceptabl e reservoirs. As long as CO2 can be injected and stored securely, with minimal c hance for breaching containment (either via wellbore or geological feat ures), proximity to USDWs, whether shallower or deeper,

should not matter.

 Minimum Injection depth vs. requirem ent to inject below lowermost USDW – BP disagrees with universal mandates for estab lishing minimum depths for CO2 injection, as these should be site-specific based on t he containment and capacity parameters of the storage site.

 Standard requirement for downhole shut-in devices -- BP disagrees with the rule to

include downhole shut-in dev ices as a standard requirement for injection wells. Overpressure protection is best achieved by ensuring compatibility of the casing/tubing material design strength with the surface injection (compression) system. Downhole shut-in devices may be appropriat e, however, for site-specific situations of unique potential impact (such as offshore or near ai rports), but they should not be mandated for all injection sites.BP Alternative Energy Comments to EPA Proposed Rule By Mr. Brian Williams

Docket ID No. EPA-HQ-OW-2008-0390 Page 3

CONCLUSION

 Wells are indeed a fundamental component of a geologic storage system. Having appropriate design, constructi on & operating requirements for these wells is necessary to ensure delivery of the secure storage of CO2.

 Site-specific performance-bas ed guidelines, like the well-rela ted examples I’ve noted, will serve the purpose of r equiring application of the appropriate technological solutions to protect USDWs.

 Again, I’d like to thank the EPA for pr oviding this opportunity to speak today.Letter ID: 0116

Commenter: Brian Williams Organization: BP A lternative Energy

Letter ID: 0116 Comment ID: 22049 Letter Lines: 30 to 41

Comment Code: 1320 1.1.3 General comments about GS

Comment Code: 1940 1.4.4.3 Consultations with Industry; experience with other wells

Comment: EPA has correctly recognized that wells are a fundamental component of a geologic storage system that successfully ensures the containment of stored CO2. As such, we agree that having appropri ate well design, constr uction & operating requirements are critical to the de livery of secure storage of CO2.

Oil and gas operators have decades of experience, via past and existing operations, in constructing and operating EO R/EGR wells in a safe and secure way. For existing EOR projects and wells, Cl ass II requirements have proven to be sufficient at ensuring the necessary protection of USDWs, and, therefore, analysis of the experiences and performa nces of these Class II CO2 EOR wells should inform the requirements for new Class VI wells.

Individual Response: EPA recognizes that the oil and gas industry has decades of experience injecting CO2 for the purpose of ER, and that site s used for ER may be suitable for GS and may be among the first GS sites. Some of the research that informs the final GS rule was conducted at ER sites. EPA also recognizes th at a by-product of ER activities is that a certain percentage of the CO2 is trapped in the receiving formation.

In addition, EPA is using an adaptive approach to regulating GS under the UIC Program. Even after finalization of the GS regul ation, the Agency plans to coll ect and review data every six years 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 approp riate or necessary.

Letter ID: 0116 Comment ID: 22050 Letter Lines: 42 to 53

Comment Code: 3862 2.3.3.1 Use of corrosion-resistant construction materials (seeking comment)

Comment Code: 3864 2.3.3.2 Use of corrosion-resistant cements (seeking comment)

Comment: I would like to comment on certain of the incremental requirements in the draft rule, including the preambl e, around the design, cons truction & ope ration of Class VI wells that we feel are potentially excessive.

1WELL CONSTRUCTION

Corrosion resistant materials & cement - Ba sed on industry expe rience and field

studies, corrosion resistant materials s hould not be mandated for all projects, and the requirement, if there is any, s hould be made on a site-specific basis. Early field studies (by th e CO2 Capture Project) i ndicate that it is the appropriate placement of cement, and not the type of cement, that delivers isolation & prevents casing corrosion.

Individual Response: EPA agrees that proper cement placement is extremely important to the integrity of a Class VI well. However, even proper cement placement cannot compensate for an improper type of cement. It is also important that the cement type be appropriately CO2 compatible and corrosion-resistant, and suitable to both the CO2 stream and formation fluids. Data from research and the field show that various cement designs are subject to chemical alteration when exposed to CO2 (e.g., Barlet-Gouedard et al., 2006; Kutchko et al., 2007; Carey et al., 2007). The rule does not specify materials to be used; rather, it provides owners or operators with the flexibility to choose, as l ong as the materials used in Class VI wells are compatible with fluids with which they may co me into contact and meet or exceed standards developed for such materials by API or ASTM In ternational, or comparable standards approved by the Director, as provi ded at §146.86(b)(1).

See the discussion of Class VI well construction requirements in the preamble to the final GS rule for additional information. Additionally, EPA is developing guidance on the construction of Class VI wells. This guidance will be available on EPA’s website at http://water.epa.gov/type/groundwater /uic/wells_sequestration.cfm.

Letter ID: 0116 Comment ID: 22051 Letter Lines: 55 to 59

Comment Code: 3862 2.3.3.1 Use of corrosion-resistant construction materials (seeking comment)

Comment Code: 3864 2.3.3.2 Use of corrosion-resistant cements (seeking comment)

Comment: The choice of casing and cement materials should be selected based on planned well operating life (i.e., decades), not on th e ultimate duration of the storage program. The potential for longer term e xposure of casing during storage, which might occur after injection has stopped, is mitigated by plugging the static

well with corrosion-resistant material, if it is deemed necessary at that time.

Individual Response: EPA disagrees that the casing, cement, or other materials should only be designed for the period of the injection process, ra ther than the life of the sequestration project. GS projects are anticipated to ha ve long life spans in comparison to other types of deep injection wells. Not only must Class VI wells be able to function safely and properly over the lifespan of the GS project, but they must be constructe d such that USDWs remain protected after well plugging. The requirements at §146.86 will ensure that the well can maintain integrity throughout the proposed life span of the project, including after the injection well is plugged and

2through the post-injec tion site care period and beyond. While th e risk profile of a GS site will decrease following cessation of in jection, EPA believes that Class VI wells must be designed to protect USDWs from endangerment for the life of the project. Furthermore, rigorous casing and cementing help ensure that the Class VI well will not serve as a conduit fo r movement of fluids

associated with future injection operations.

Letter ID: 0116 Comment ID: 22052 Letter Lines: 61 to 71

Comment Code: 3824 2.3.1.2 Cementing of long-string casing (seeking comment)

Comment: Cement across long string casing -- BP doe s not agree with the requirement for a long string from the injection interval to surface or with cementing across that

entire distance. Allowance should be made for a liner to be set across the injection interval when the previous st ring is set above that zone. Cement should cover the uppermost caprock in th e Area of Review by a margin of approximately 500 feet, not to surface. The ultimate decision for each project

should rest with the Director since each is unique in the ge ological intervals of the caprock(s) and injec tion zone(s) and of the positi on relative to USDW(s). Any expectation to cement in the injection interval should permit the use of external casing packers in conjunction with the cementing requirements across the caprock.

Individual Response: The final GS rule at §146.86(b)(3) re quires that the long-string casing extend to the injection zone and be cemented by ci rculating cement to the surface in one or more stages. It does not, however, specify how cementing would be accomplished, and gives flexibility to the owner or ope rator to propose alternate methods to provide a sufficient amount

of cement to meet the standard that USDWs ar e protected from endangerment, subject to the approval of the Director. EPA adds that, unde r §146.86(b)(4), the Dire ctor may approve an alternative method of cementing in cases where the cement cannot be recirculated to the surface, provided the owner or operator can demonstrate by using logs th at the cement does not allow

fluid movement behind the wellbore.

The construction requirements at §146.86 offer flex ibility to the owner or operator to propose well construction procedures that are appropriate to the site-speci fic conditions of the project. With their permit applications, operators must submit well construction pr ocedures, as specified at §146.82(a)(12), that demonstrate that the well as constructed will prevent unacceptable fluid movement; allow the use of appropriate tes ting devices and workove r tools; and allow continuous monitoring of the annul us space between the injection tubing and long-string casing, as specified at §146.86(a). The Dire ctor will evaluate the propos ed well construction procedures

in the context of other data about the site. EPA has evaluated the cementing requirements for other well classes and believes that flexibility can be afforded while ensuring that USDWs are protected.

See the discussion of Class VI well construction requirements in the preamble to the final GS rule for additional information. Additionally, EPA is developing guidance on the construction of

3Class VI wells. This guidance will be available on EPA’s website at http://water.epa.gov/type/groundwater /uic/wells_sequestration.cfm.

Letter ID: 0116 Comment ID: 22053 Letter Lines: 75 to 81

Comment Code: 4324 2.4.4.1.2 Comments opposed to requiring injection below the lowermost

USDW

Comment: No CO2 injection above lowest known USDW -- BP does not subscribe to a blanket,

artificial constraint that would limit in jection only to reservoirs below the USDW. More appropriate, gi ven the EPA’s general perf ormance-based approach, would be to place containment requirement s on the acceptable reservoirs. As long as CO2 can be injected and stored secu rely, with minimal chance for breaching containment (either via well bore or geological features), proximity to USDWs, whether shallower or deep er, should not matter.

Individual Response: EPA acknowledges that there are lim ited circumstances where injection above the lowermost USDW can be performe d in a manner that protects USDWs from endangerment, as long as appropriate protections are in place. The final GS rule at §146.95 establishes a process by which owne rs or operators can seek a waiv er of the Class VI injection depth requirements for injecti on into non-USDW formations above and/or between USDWs. The

final rule also establishes limited circumstances under which expansions of the areal extent of aquifer exemptions may be granted for owne rs or operators of Class II EOR/EGR wells transitioning to Class VI injec tion for GS. Additionally, the final GS rule does not categorically preclude or prohibit in jection into any type of formation.

EPA believes that these requirements will ensure USDW protection while providing flexibility to UIC program Directors and owne rs or operators who undertak e CO2 injection for GS. The Agency believes this approach: 1) responds to co ncerns about local and re gional geologic storage capacity limitations imposed by th e proposed injection depth require ments; 2) allows for a more site-specific assessment of injection depth for GS projects; 3) accommodates injection into different formation types; 4) a llows for injection of CO2 for GS into non-USDWs above and/or between USDWs when appropriate and where it can be demonstrated that USDWs will be protected; and 5) responds to concerns about the use of aqui fer exemptions for GS. Finally, EPA’s approach to addressing injection depth va riability through a waiver process responds to concerns about future drinking wa ter resource availability and the need to ensure that high quality water remains available in sufficient qua ntities to supply drinking water needs. For additional information on the waiver approach and aquifer exemptions for Class VI wells, please see the final rule and preamble, as well as EP A's responses to comments on the Notice of Data Availability and Request for Comment.

Letter ID: 0116 Comment ID: 22054 Letter Lines: 83 to 86

Comment Code: 4344 2.4.4.2.2 Comments opposed to setting a minimum injection depth

4Comment: Minimum Injection depth vs. requirement to inject below lowermost USDW - BP disagrees with universal mandates for es tablishing minimum depths for CO2 injection, as these should be site-sp ecific based on the containment and capacity parameters of the storage site.

Individual Response: EPA agrees that it is not appropriate to set a mi nimum injection depth for GS projects and the Agency believes that a determ ination of site-suitabili ty for GS (i.e., that

subsurface formations will receiv e and confine injected CO2) s hould be made on a site-specific basis. The GS rule, at §146.82, requires the owne r or operator to provide extensive site- and project-specific information to the Director to demonstrate that the site meets the minimum site criteria at §146.83, that the CO2 will be contai ned within the injection formation, and that USDWs will be protected from endangerment.

EPA acknowledges that there are limited circum stances where injectio n above the lowermost USDW can be performed in a manner that protec ts USDWs, as long as appropriate protections are in place. The final GS rule at §146.95 establis hes a process by which owners or operators can seek a waiver of the Class VI injection de pth requirements for in jection into non-USDW

formations above and/or between USDWs. The waiver approach requires the submission of extensive, site-specific information (in conjunc tion with the permit appl ication submission) to demonstrate that injection of CO2 into a non-US DW that is above or between USDWs can be done in a manner that is protective of USDWs. Th e requirements are designed to ensure that the owner or operator, the Director, and the Regional Administrator cons ider, on a site specific basis, the implications, benefits, and challenges associat ed with GS and ensuring water availability and USDW protection. For additional information on the waiver approach, please see the final rule and preamble, as well as EPA's responses to comments on the Notice of Data Availability and Request for Comment.

Letter ID: 0116 Comment ID: 22055 Letter Lines: 88 to 94

Comment Code: 4200 2.4.2 Down-hole shut-off valves in GS wells (seeking comment)

Comment: Standard requirement for downhole shut-in de vices -- BP disagrees with the rule

to include downhole shut-in devices as a standard requirement for injection wells. Overpressure protection is best ach ieved by ensuring compatibility of the casing/tubing material design strength w ith the surface injection (compression) system. Downhole shut-in devices may be appropriate, however, for site-specific situations of unique potential impact (suc h as offshore or near airports), but they should not be mandated for all injection sites.

Individual Response: EPA agrees that proper design of the well, including appropriate materials and emplacement of casing and tubing, is essential to proper operation of the well. Such design,

however, does not eliminate the possibility of failure, e.g., due to over-pressurization as suggested by the commenter. EPA believes that a multiple-barrier approach, which includes appropriate well design as requi red at §146.86, suitable injection pressure limits as required at §146.88(a), and automatic shut-off systems, as re quired at §146.88(e), is necessary to ensure protection of USDWs from endangerment fr om the risks associ ated with CO2 GS.

5After evaluating the risk s and benefits of down-hole shut-off systems and considering additional research, EPA will not require automatic down-ho le shut-off devices for onshore Class VI wells since it is not necessary in all cases to ensure protection of USDWs from endangerment. Instead, the final rule, at §146.88(e)(2), re quires that owners or operato rs of onshore Class VI wells

install automatic surface shut-off devices. The ru le affords Director's discretion to mandate

automatic down-hole shut-off devices in onshore situ ations that may warrant their use. However, the Agency agrees with the commenter that o ffshore Class VI wells present unique construction and operational conditions, including isolation from shorelines and the need to construct wells through the water column and the subsurface, wh ich may delay response time in the event of well difficulties. The rule requires, at §146.88(e)(3), that owners or operators of offshore wells

within State territorial waters install automatic down-hole shut-off systems. EPA believes that these requirements at §146.88(e) ensure that proper precautions are taken to prevent subsurface fluid movement and ensure protection of USDWs.

Letter ID: 0116 Comment ID: 22056 Letter Lines: 98 to 104

Comment Code: 1250 1.1.1.4 Flexibility is needed (p erformance-based standards)

Comment: Wells are indeed a fundamental component of a geologic storage system. Having appropriate design, construction & operati ng requirements for these wells is necessary to ensure delivery of the secure storage of CO2.

Site-specific performance-ba sed guidelines, like the we ll-related examples I’ve noted, will serve the purpose of requiri ng application of the appropriate technological solutions to protect USDWs.

Individual Response: The Agency believes that the Class VI requirements balance site-specific flexibility with USDW protection. Rather than setting performance or technology-based standards for GS projects, EPA is adopting a flex ible approach, where operators of GS projects would develop and implement site-specific plans for delineating the AoR, testing and monitoring the site, performing corrective actio n, and post-injection site care . EPA believes that the plans— which would be reviewed and approved by the Director and periodical ly updated throughout the life of the project—promote an ongoing dialogue between the operato r and the Director that will encourage use of the most appropriate t echnologies for a particular project.

6