UNITED STATES GOVERNMENT MEMORANDUM

To: Public Information (MS 5030) Plans Section, Office of Field Operations (MS 5231)

Public Information copy of Exploration Plan Control # - N-09702 Type - Initial Exploration Plan Lease(s) - OCS-G34444 Block - 554 Mississippi Canyon Area OCS-G34445 Block - 555 Mississippi Canyon Area Operator - Apache Deepwater LLC Subsea Well A (MC 554) and Subsea Wells A and B (MC 555)

Not Found

Attached is a copy of the subject plan for public comments on issues that should be addressed in an Environmental Assessment.
It has been deemed submitted as of this date and is under review for approval.

Karen Dunlap Plan Coordinator Description - Rig Type - Subject: From: May 10, 2013PUBLIC COPY



## RECORD OF CHANGES

Operator: Apache Deepwater LLC 

## Lease: OCS-G 34444/34445 

## Area/Block: Mississippi Canyon Blocks 554/555 

## Plan Type: Joint Initial Exploration Plan 

## Plan Control No.: N-9702 

## Plan Submitted: April 25, 2013 

## BOEM Coordinator: Karen Dunlap



## Date Appendix Page Revision 3/6/2013 H Submit .nod and .mer files, previous not able to open 3/13/2013 H Submit .nod file again, BOEM having trouble opening previous one again 3/28/2013 A All Storage Tanks table - revised total capacity for dirty lube oil3/28/2013 BOEM-0137 Answer YES to question regarding "disturbing a highprob arch area, revise anchor radius to 11,500 to be consistent with Site Clearance Letters 3/28/2013 B B-1 Revise the drilling fluids chart 3/28/2013 C C-4 Revise all Site Clearance Location Letters with thecorrect anchor radius to be consistent with the BOEM0137 form 3/28/2013 E Revise the verbiage to state an arch report was submitted and to be consistent with the EIA 3/28/2013 F F-1 Revise Waste & Discharge tables to explain completion of the wells 3/28/2013 G Attach the calculation spreadsheets 3/28/2013 H H-1 OSRP currently under USCG review, will resubmit after given approval 3/28/2013 L L-1 Revise Support Vessels table, remove unnecessary information not required 4/18/13 H H-1 OSRP Approval 4/18/13

# JOINT INITIAL EXPLORATION PLAN

PUBLIC COPY

April 25, 2013

Area/Block: Mississippi Canyon Blocks 554/555 Lease Number(s): OCS-G 34444/34445 Prospect Name: Guadalupe Offshore: Louisiana

Prepared By:
Ms. Terri Young Apache Deepwater LLC 2000 W. Sam Houston Pkwy. S., Suite 1600 Houston, Texas 77042 (713) 296-7456 Terri.young@apachecorp.com

Plan No.: 9702 Assigned to: Karen Dunlap 

## Date of Submittal: April 25, 2013 Estimated Start-up Date : September 15, 2013

### JOINT INITIAL EXPLORATION PLAN DOCUMENT LEASE OCS-G 34444/34445 MISSISSIPPI CANYON BLOCKS 554/555

TABLE OF CONTENTS

SECTION A Plan Contents

SECTION B General Information

SECTION C Geological, Geophysical Information

SECTION D H2S Information

SECTION E Biological, Physical and Socioeconomic Information

SECTION F Wastes and Discharge Information

SECTION G Air Emissions Information

SECTION H Oil Spills Information

SECTION I Environmental Monitoring Information

SECTION J Lease Stipulations Information

SECTION K Environmental Mitigation Measures Information

SECTION L Support Vessels and Aircraft Information

SECTION M Onshore Support Facilities Information

SECTION N Coastal Zone Management Act (CZMA) Information

SECTION O Environmental Impact Analysis

SECTION P Administrative Information

### LIST OF ATTACHMENTS

A-1 OCS Plan Information Form

A-2 Well Location Plat
A-3 Bathymetry Map
A-4 Pay.Gov Receipt

C-4 Shallow Hazard Assessment
F-1 Projected Generated Wastes
H-1 Spill Response Discussion for NEPA Analysis
L-1 Solid and Liquid Waste Transportation
L-2 Vicinity Map
N-1 Coastal Zone Management Consistency Certification
O-1 Environmental Impact AnalysisApache Deepwater LLC Page A

‐ 1 Joint Initial Exploration Plan April 25, 2013 Mississippi Canyon Blocks 554/555 (OCS

‐ G 34444/34445) 

### SECTION A PLAN CONTENTS (30 CFR 550.211 and 550.241)

A. PLAN INFORMATION FORM Apache Deepwater LLC submits this Joint Initial Exploration Plan to propose the drill and completion of three (3) well locations in Mississippi Canyon Blocks 554/555. Tentative schedules from start to finish of the drilling a nd completion activities and information regarding the proposed locations are included on the OCS Plan Information Form BOEM-0137, included

as Attachment A-1.

B. LOCATION A Well Location Map depicting the proposed surface locations for the proposed wells is included

as Attachment A-2 . A Bathymetry Map showing the wate r depths across the lease block is included as Attachment A-3 . These attachments are in accorda nce with the Notice to Lessees (NTL) 2008-G04.

C. SAFETY AND POLLUTION PREVENTION FEATURES A description of the drilling unit is included on the OCS Plan Information Form. Rig specifications will be made part of each Application for Permit to Drill (APD).
Safety features on the drilling unit will include well control, pollution prevention and blowout prevention equipment as described in Title 30 CF R Part 550, Subparts C, D, E and F; and as further clarified by BOEM Notices to Lessees and current policy making invoked by the BOEM Environmental Protection Agency and the U.S. Coast Guard.
Appropriate life rafts, life jackets, ring buoys, etc., will be maintained on th e facility at all times as mandated by the U.S. Coast Guard regulations contained in Title 33 CFR.
Pollution prevention measures include installation, of curbs, gutters, drip pans and drains on drilling deck areas to collect all contaminants and debris.Apache Deepwater LLC Page A

‐ 2 Joint Initial Exploration Plan April 25, 2013 Mississippi Canyon Blocks 554/555 (OCS

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### D. STORAGE TANKS AND/OR PRODUCTION VESSELS The Mississippi Canyon Blocks 554/555 wells will be drilled with a Semisubmersible or DP Semisubmersible unit. All facility tanks of 25 barrels or more.

Type of Storage Tank Type of Facility (Rig) Tank Capacity

(bbls) Number of Tanks Total Capacity

(bbls) Fluid Gravity

(APIDegree) Fuel Oil (Marine Diesel) Semisubmersible 104.7 1 104.7 35 o 

### Fuel Oil Day Semisubmersible 97.6 1 97.6 35 o 

### Emergency Generator Semisubmersible 5.5 1 5.5 35 o 

### Forward Hull – Fuel Oil Semisubmersible 3416 1 3416 35 o 

### Lower AFT Hull – Fuel Oil Semisubmersible 3416 1 3416 35 o 

### Lube Oil Services Semisubmersible 61.3 7 429.1 26 o 

### Dirty Lube Oil Semisubmersible 30.1 1 30.1 26 o 

### Dirty Bilge Semisubmersible N/A N/A N/A N/A Fuel Oil (Marine Diesel) DP Semisubmersible 164 1 164 35 o 

### Fuel Oil Day DP Semisubmersible 262 1 262 35 o 

### Emergency Generator DP Semisubmersible 30.76 1 30.76 35 o 

### Forward Hull – Fuel Oil DP Semisubmersible 4540.9 2 9081.84 35 o 

### Lower AFT Hull – Fuel Oil DP Semisubmersible 6790 2 13580 35 o 

### Lube Oil Services DP Semisubmersible 115 1 115 26 o 

### Dirty Lube Oil DP Semisubmersible 33 2 66 26 o 

### Dirty Bilge DP Semisubm ersible N/A N/A N/A N/A

E. ADDITIONAL MEASURES Apache Deepwater does not prop ose additional safety, polluti on prevention or early spill detection measures beyond those required by 30 CFR 550.

F. COST RECOVERY FEE A Pay.Gov receipt in the amount of $11,019.00 for the cost recover fees associ ated with this plan is included as Attachment A-4.

### U.S. Department of the Interior OMB Control Number: 1010-0151 Bureau of Ocean Energy Management OMB Approval Expires: 12/31/2014 

### OCS PLAN INFORMATION FORM General Information Type of OCS Plan: Exploration Plan (EP) Development Operations Coordination Document (DOCD) Company Name: BOEM Operator Number:
Address: Contact Person:
Phone Number:
E-Mail Address: Lease(s): Area: Block(s): Project Name (If Applicable): Objective(s): Oil Gas Sulphur Salt Onshore Base: Distance to Closest Land (Miles): Description of Proposed Activities (Mark all that apply) Exploration drilling Development drilling Well completion Installation of production platform Well test flaring (for more than 48 hours) Installation of production facilities Installation of caisson or platform as well protection structure Installation of satellite structure
Installation of subsea wellheads and/or manifolds Commence production Installation of lease term pipelines Other (Specify and describe) Have you submitted or do you plan to submit a Conservation Information Document to accompany this plan? Yes No Do you propose to use new or unusual technology to conduct your activities? Yes No Do you propose any facility that will serve as a host facility for deepwater subsea development? Yes No Do you propose any activities that may disturb an BOEM-designated high-probability archaeological area? Yes No Have all of the surface locations of your proposed activities been previously reviewed and approved by BOEM? Yes No Tentative Schedule of Proposed Activities Proposed Activity Start Date End Date No. of Days 

Description of Drilling Rig Description of Production Platform Jackup Drillship Caisson Tension leg platform Gorilla Jackup Platform rig Well protector Compliant tower
Semisubmersible Submersible Fixed platform Guyed tower
DP Semisubmersible Other (Attach Description) Subsea manifold Floating production system Drilling Rig Name (If Known): Spar Other (Attach Description) Description of Lease Term Pipelines From (Facility/Area/Block) To (Facility/Area/Block) Diameter (Inches) Length (Feet) 

FORM BOEM-0137 (December 2011

- Supersedes all previous editions of form BOEM-0137 which may not be used.) Page 1 of 2 ATTACHMENT A-1

Apache Deepwater LLC 03165 2000 W. Sam Houston Pkwy, South Terri Young

Suite 1600 713-296-7456 Houston, TX 77042 terri.young@apachecorp.com

OCS-G 34444/34445 MC 554/555 Guadalupe
X Martin Fuel Docks, Fourchon, LA 50

X

X

X

X
X
X
X
X

Drill, complete and test three (3) locations and install subsea wellheads

MC 555 Location A 9/15/2013 12/18/2013 94

MC 554 Location A 1/1/2014 4/5/2014 94

MC 555 Location B 1/1/2015 4/5/2015 94

X

XOCS PLAN INFORMATION FORM ( CONTINUED ) Include one copy of this page for each proposed well/structure Proposed Well/Structure Location Well or Structure Name/Number (If renaming well or structure, reference previous name): Previously reviewed under an approved EP or DOCD? Yes No

Is this an existing well or structure? Yes No If this is an existing well or structure, list the Complex ID or API No. Do you plan to use a subsea BOP or a surface BOP on a floating facility to conduct your proposed activities? Yes No

WCD info For wells, volume of uncontrolled blowout (Bbls/day): For structures, volume of all storage and pipelines (Bbls): API Gravity of fluid Surface Location Bottom-Hole Location (For Wells) Completion (For multiple completions, enter separate lines) Lease No. OCS OCS OCS OCS Area Name

Block No.

Blockline Departures (in feet) N/S Departure: F____ L N/S Departure: F____ L N/S Departure: F____ L N/S Departure: F____ L N/S Departure: F____ L E/W Departure: F____ L E/W Departure: F____ L E/W Departure: F____ L E/W Departure: F____ L E/W Departure: F____ LLambert XY coordinates X: X: X: X: X: Y: Y: Y: Y: Y: Latitude/ Longitude Latitude Latitude Latitude Latitude Latitude Longitude Longitude Longitude Longitude Longitude Water Depth (Feet): MD (Feet): TVD (Feet):

Anchor Radius (if applicable) in feet: MD (Feet): MD (Feet): MD (Feet): TVD (Feet): TVD (Feet): TVD (Feet):
Anchor Locations for Drilling Rig or Construction Barge ( If anchor radius supplied above, not necessary)
Anchor Name or No. Area Block X Coordinate Y Coordinate Length of Anchor Chain on Seafloor

X = Y =

X = Y =

X = Y =

X = Y =

X = Y =

X = Y =

X = Y =

X = Y =

Form BOEM- 0137 (December 2011

- Supersedes all previous editions of this form which may not be used.) Page 2 of 4 A 

## X

X
X 

## 32

G-34444 

### Mississippi Canyon
554

S 

## 7,721'

E 

## 631'


# 1,108,169'
10,319,561'

28.4266452

-88.6563833

4,647' 

## 11,500' 444,250OCS PLAN INFORMATION FORM ( CONTINUED ) Include one copy of this page for each proposed well/structure Proposed Well/Structure Location Well or Structure Name/Number (If renaming well or structure, reference previous name): Previously reviewed under an approved EP or DOCD? Yes No

Is this an existing well or structure? Yes No If this is an existing well or structure, list the Complex ID or API No. Do you plan to use a subsea BOP or a surface BOP on a floating facility to conduct your proposed activities? Yes No

WCD info For wells, volume of uncontrolled blowout (Bbls/day): For structures, volume of all storage and pipelines (Bbls): API Gravity of fluid Surface Location Bottom-Hole Location (For Wells) Completion (For multiple completions, enter separate lines) Lease No. OCS OCS OCS OCS Area Name

Block No.

Blockline Departures (in feet) N/S Departure: F____ L N/S Departure: F____ L N/S Departure: F____ L N/S Departure: F____ L N/S Departure: F____ L E/W Departure: F____ L E/W Departure: F____ L E/W Departure: F____ L E/W Departure: F____ L E/W Departure: F____ LLambert XY coordinates X: X: X: X: X: Y: Y: Y: Y: Y: Latitude/ Longitude Latitude Latitude Latitude Latitude Latitude Longitude Longitude Longitude Longitude Longitude Water Depth (Feet): MD (Feet): TVD (Feet):

Anchor Radius (if applicable) in feet: MD (Feet): MD (Feet): MD (Feet): TVD (Feet): TVD (Feet): TVD (Feet):
Anchor Locations for Drilling Rig or Construction Barge ( If anchor radius supplied above, not necessary)
Anchor Name or No. Area Block X Coordinate Y Coordinate Length of Anchor Chain on Seafloor

X = Y =

X = Y =

X = Y =

X = Y =

X = Y =

X = Y =

X = Y =

X = Y =

Form BOEM- 0137 (December 2011

- Supersedes all previous editions of this form which may not be used.) Page 2 of 4 A 

## X

X
X

G-34445 

### Mississippi Canyon
555

S 

## 8,195'

W 

## 357'


# 1,109,157'
10,320,035'

28.4279862

-88.6533299

4,651' 

## 11,500'OCS PLAN INFORMATION FORM ( CONTINUED ) Include one copy of this page for each proposed well/structure Proposed Well/Structure Location Well or Structure Name/Number (If renaming well or structure, reference previous name): Previously reviewed under an approved EP or DOCD? Yes No

Is this an existing well or structure? Yes No If this is an existing well or structure, list the Complex ID or API No. Do you plan to use a subsea BOP or a surface BOP on a floating facility to conduct your proposed activities? Yes No

WCD info For wells, volume of uncontrolled blowout (Bbls/day): For structures, volume of all storage and pipelines (Bbls): API Gravity of fluid Surface Location Bottom-Hole Location (For Wells) Completion (For multiple completions, enter separate lines) Lease No. OCS OCS OCS OCS Area Name

Block No.

Blockline Departures (in feet) N/S Departure: F____ L N/S Departure: F____ L N/S Departure: F____ L N/S Departure: F____ L N/S Departure: F____ L E/W Departure: F____ L E/W Departure: F____ L E/W Departure: F____ L E/W Departure: F____ L E/W Departure: F____ LLambert XY coordinates X: X: X: X: X: Y: Y: Y: Y: Y: Latitude/ Longitude Latitude Latitude Latitude Latitude Latitude Longitude Longitude Longitude Longitude Longitude Water Depth (Feet): MD (Feet): TVD (Feet):

Anchor Radius (if applicable) in feet: MD (Feet): MD (Feet): MD (Feet): TVD (Feet): TVD (Feet): TVD (Feet):
Anchor Locations for Drilling Rig or Construction Barge ( If anchor radius supplied above, not necessary)
Anchor Name or No. Area Block X Coordinate Y Coordinate Length of Anchor Chain on Seafloor

X = Y =

X = Y =

X = Y =

X = Y =

X = Y =

X = Y =

X = Y =

X = Y =

Form BOEM- 0137 (December 2011

- Supersedes all previous editions of this form which may not be used.) Page 2 of 4 B 

## X

X
X

G-34445 

### Mississippi Canyon
555

S 

## 4,461'

W 

## 7,791'


# 1,116,591'
10,316,301'

28.4179954

-88.6300449

4,760' 

## 11,500'Exxon-Mobil 1 

# 554

598 510

555

599 511

Y = 10,327,680'

Y = 10,311,840'X = 1,092,960'X = 1,108,800'X = 1,124,640'



### SURFACE LOCATION MAP

1/28/13 1" = 4000' 

### APACHE DEEPWATER, LLC Mississippi Canyon 554/555 OCS-G 34444/34445 APA MC 554 Loc.A APA

MC 555 Loc.A

APA MC 555 Loc.B SL SL

SL Apache Loc. MC 554 A Surface Location Apache Loc. MC 555 A Surface Location Apache Loc. MC 555 B Surface Location 7,721’ FSL & 631’ FEL of MC 554

X = 1,108,169' Y = 10,319,561' Lat. = 28.4266452 28 25' 35.932" Long. = -88.6563833 -88 39' 22.980" 8,195’ FSL & 357’ FWL of MC 555 X = 1,109,157' Y = 10,320,035' Lat. = 28.4279862 28 25' 40.750" Long. = -88.6533299 -88 39' 11.988" 4,461’ FSL & 7,791’ FWL of MC 555 X = 1,116,591' Y = 10,316,301' Lat. = 28.4179954 28 25' 04.783" Long. = -88.6300449 -88 37' 48.162"7,721' FSL8,195' FSL4,461' FSL357' FWL631' FEL

7,791' FWLExxon-Mobil 1 

# 554

598 510

555

599 511

Y = 10,327,680'

Y = 10,311,840'X = 1,092,960'X = 1,108,800'X = 1,124,640'



### BATHYMETRY MAP

1/28/13 1" = 4000' C.I. = 20' 

### APACHE DEEPWATER, LLC Mississippi Canyon 554/555 OCS-G 34444/34445 -4,500' -4,600'

-4,700' -4,800'

-4,900'

-4,900' APA

MC 554 Loc.A APA

MC 555 Loc.A

APA MC 555 Loc.B SL SL

SLOnline Payment 

### Step 3: Confirm Payment 1 | 2 | 3 Thank you. Y our transaction has been successfully completed.

Pay.gov Tracking Information Application Name: BOEM Exploration Plan - BF Pay.gov Tracking ID: 259Q4AQ0 Agency Tracking ID: 74417580865 Transaction Date and Time: 03/01/2013 12:22 EST Payment Summary
Address Information Account Holder Name: Mariner Energy, Inc.

Billing Address: 2000 W. Sam Houston Pkwy. S, Suite 2000 Billing Address 2: City: Houston State / Province: TX Zip / Postal Code: 77042 Country: USA Account Information Card Type: American Express Card Number: ************4008 Region: Gulf of Mexico

Contact: Terri Young 713-296- 7456 Company Name/No: Apache Deepwater LLC, 03165 Lease Number(s): 34444, 34445, , ,

Area-Block: Mississippi Canyon MC, 554: Mississippi Canyon MC, 555: , : , :

, Surface Locations: 3 Payment Information Payment Amount: $11,019.00 Transaction Date and Time: 03/01/2013 12:22 EST 

### Pa g e 1 of 1 Pa y

. g ov - Online Pa y ment

3/1/2013 htt p s://www. p a y

. g ov/ p a yg ov/ p a y ments/authorizePlasticCardPa y ment.htmlApache Deepwater LLC Page B

‐ 1 Joint Initial Exploration Plan April 25, 2013 Mississippi Canyon Blocks 554/555 (OCS

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### SECTION B GENERAL INFORMATION (30 CFR 550.213 and 550.243)

A. APPLICATIONS AND PERMITS The table below lists the additional permits/applications to be filed before operations can commence under this EP: Application/Permit Issuing Agency Status Application for Permit to Drill (APD) BSEE To be submitted

B. DRILLING FLUIDS Type of Drilling Fluid Estimated Volume of Drilling Fluid to be Used per Well Water-based (seawater, freshwater , barite) 40,000 bbl / well total Oil-based (diesel, minerals, oil) 0 bbl / well total Synthetic-based (internal olefin , ester) 14,255 bbls / well total Product Name Amount to be Used M-I Bar 3,152,000 lbs / well total Synthetic B 568,225 gal / well total

Suremul 14,560 gal / well total Surewet 4,625 gal / well total Rheflat 1,660 gal / well total Rhethik 1,245 gal / well total

Lime 46,250 lbs / well total Calcium Chloride 134,300 lbs / well total

C. NEW OR UNUSUAL TECHNOLOGY Apache Deepwater does not propose to use an y new or unusual technology to carry out the proposed exploration activities.

D. BONDING STATEMENT The bond requirements for the activities and facili ties proposed in this EP are satisfied by a $3,000,000.00 areawide development bond, furnished and maintained according to 30 CFR 256 subpart I; NTL No. 2000-G16 - “Guidelines for General Lease Surety Bonds”; and additional security under 30 CFR 256.53(d) and Natio nal NTL No. 2008-N07 - “Supplemental Bond Procedures”.Apache Deepwater LLC Page B

‐ 2 Joint Initial Exploration Plan April 25, 2013 Mississippi Canyon Blocks 554/555 (OCS

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### E. OIL SPILL FINANCE RESPONSIBILITY (OSFR) Apache Deepwater LLC, (company number 03165) has demonstrated oil spill financial responsibility for the facilities proposed in this EP according to 30 CFR Part 253 and NTL No. 2008-N05 - “Guidelines for Oil Spill Financial Responsibility for Covered Facilities”.

F. DEEPWATER WELL CONTROL STATEMENT Apache Deepwater LLC, (company number 03165) has the financial capabil ity to drill a relief well and conduct other emergency well control operations.

G. BLOWOUT SCENARIO Estimated maximum flow rate
The estimated maximum flow rate would occur in the objective section, if a kick were taken and the well blew out. The maximum Worst Case Disc harge (WCD) modeled for this scenario is 444,250 BOPD. Maximum duration of blowout (days) The duration of the blowout will be a function of the well bridging over, the ability of surface intervention to shut or contain the well or, as a last resort, dr illing a relief well to kill the blowout. The expected maximum time frames fo r uncontrolled flow in each of the different operational outcomes would be as follows:

 Bridging Over in 2 Days,

 Surface Intervention in 15 Days,

 A Relief Well in 101 Days.
Maximum discharge volume The following table is a linear estimate of th e maximum discharge volume for each of the aforementioned operational outcomes. Operational

Outcome Maximum Discharge Rate (bbl/day) Discharge Duration

(days) Maximum Discharge Volume (bbl) Bridging Over 444,250 2 888,500
Surface Intervention 444,250 15 6,663,750

Relief Well 444,250 101 44,869,250

Potential of wellbore to bridge over during a blowout There is significant potential for the wellbore to bridge over during the WCD blowout. Bridging is likely to occur due to the extreme drawdow n calculated between the formation and the open hole section. A Merlin reservoir simulation mode l was used to investigate the well conditions during the WCD blowout scenario. The estimated reservoir pressure is 18,460 psi. The reservoirApache Deepwater LLC Page B

‐ 3 Joint Initial Exploration Plan April 25, 2013 Mississippi Canyon Blocks 554/555 (OCS

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### model estimates bottom hole flowing pressures, ba sed upon reservoir properties and flow rates. The calculated drawdown is modeled to be 8,403 psi. In our experience in the deepwater GOM, we stri ve to limit the estimated total drawdown on a producing interval to reduce the risk of wellbore collapse and sand/fines migration into a well. We limit the drawdown to less th an 1,000 psi by reducing the ra tes the wells produce and by completing each well with a cased hole, frac-pack completion. There is a strong likelihood of wellbore bridging over:

 Drawdown is estimated to be 8.4 times or greater than our operating practices,

 The blowout occurs in a long open hole s ection of the well, with no benefit of casing or a frac-pack completion,

 If any water zones are exposed this will accelerate wellbore collapse and bridging,

 Wellbore collapse and bridge-over, under th e conditions cited are estimated not to exceed 2 days.

Surface intervention to stop the blowout In the event of a blowout and assuming the blow out prevention equipment is still intact; the subsea BOP will be used for succes sful shut-in of the well. The well would then be killed and re-entered to either abandon or return to norm al operations. Surface intervention would be the first line of defense after a blowout occurs. The specific intervention technique chosen will depend on actual conditions and abil ity to access the existing well. In the event that the subsea BOP is inoperable, the surface intervention would employ the Marine Well Containment Company (MWCC) containment sy stem to achieve successful containment of the well. The system will be employed, while simultaneously initiating relief well planning and operations. Specifics will be submitted within the Well Containment Plan. Typically blowouts can be controlled with surf ace intervention, with a good likelihood of success and in a relatively short time frame, as long as, the subsea casing, wellhead and BOP’s are not damaged beyond use. The intervention technique chosen will depend on actual conditions and ability to access the existing well. There can be simple solutions such as rig up and bullhead kill mud or more complex solutions, but the solution will depend on wellbore conditions.

Surface intervention time estimate The assumption is that the well has an uncont rolled blowout and the MODU has sunk with displacement from the wellhead. Additionally, it assu mes that debris removal will be required to gain access to the subsea BOP system. The ROV has been deployed and was unsuccessful in shutting in the well, using the existing subsea BOP control panel. The scenario employs the aforementioned containment system’s capping BOP. The table on the next page describes the estimated time required to shut in and secure the well using the containment system or capping stack. Note that these operations all basically start at the same point in time and are performed in para llel. The entire operation is estimated to take 15 days from start of site assessment until the capping stack has been deployed and the well shut in.Apache Deepwater LLC Page B

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### Duration of a well capping operation Operation Incremental Duration

(days) Cumulative Time Since Event Start (days) Assess wellbore conditions for surface intervention requirements. Conduct notifications to the regulatory agencies and primary contractors. 2 2

Site Preparation which includes mobilizing and deployment of the IWOCS system and Dispersant system. 5 5

Debris removal including mobilization of ROV boat and construction support vessel and execution of debris removal plan. 7 7

Well capping and/or cap and flow operations which include mobilization, deployment, and installation of the well containment system. 15 15

Relief Well It is preferred to drill relief wells from an open water location, rather than a platform location. Open water locations provide the best option on designing a simpler intercept well and allow a greater choice on rig availability. There are not a ny platforms in the vicinity; therefore it is not feasible to consider a platform as a relief well location.

Relief well location and drilling strategy Proprietary InformationApache Deepwater LLC Page B

‐ 5 Joint Initial Exploration Plan April 25, 2013 Mississippi Canyon Blocks 554/555 (OCS

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### Relief well rig availability The rigs listed below could be ava ilable for relief well operations:

Rig Name Contractor Rated Water Depth MODU Type Rig Status

Ensco 8500 Ensco 8,500’ DP Semisubmersible Contracted GOM Ensco 8501 Ensco 8,500’ DP Semisubmersible Contracted GOM Ensco 8502 Ensco 8,500’ DP Semisubmersible Contracted GOM Ensco 8506 Ensco 8,500’ DP Semisubmersible Contracted GOM West Sirius Seadrill 10,000’ DP Semisubmersible Contracted GOM Maersk Developer Maersk 10,000’ DP Semisubmersible Contracted GOM

Danny Adkins Noble 12,000’ DP Semisubmersible Contracted GOM

C.R. Luigs Transocean 10,000’ DP Drill Ship Contracted GOM Discoverer Deep Seas Transocean 10, 000’ DP Drill Ship Contracted GOM

Relief well package constraints The proposed rigs for relief well operations have suitable drilling packages with sufficient capabilities to work in the subject water depths and drill to the required relief well depth. The BOP systems have met the BSEE certification require ments and will be re-inspected in transit, prior to drilling a relief well to th e required true vertical depth.

Relief well rig contract and mobilization timing A suitable rig could be selected and a contra ct finalized in 48 hours after undertaking the decision to begin relief well operations. Ba ckup tubular goods and wellhead systems are maintained in stock for each well. Mobilization of equipment and services to the rig for the relief well could be completed while operations required to suspend the rig’s current activity were taking place. The time required to contract, mobilize, drill a relief well and kill the blowout well is estimated at 101 days and is summarized below. The relief well, MC 555 Location A, was used for this example.Apache Deepwater LLC Page B

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‐ G 34444/34445) 

### Duration of relief well Description Days Cumulative Days Well Control Assessment. Identify suitable MODU for relief well operations 2 2
MODU suspends operations from current well. Contract to be executed and Well Spud Equipment is mobilized 14 16

Mobilize Rig and install 36” Structural Casing 10 26 Spud and drill to the top of the zone of interest and set casing. 65 91
Mag-Range relief well into intersecting position. 5 96 R/U pumping equipment and kill well. 5 101 R/D Pumping Equipment, PA Wellbore, Pull Riser, and Demobilize 15 116

Blowout Prevention and Intervention Summary of prevention measures Apache Deepwater LLC has maintained a safe track record of prudent op erations in the GOM deepwater environment. It will continue to implement its safe operating practices to enhance its operating risk reduction program. In addition to the safe operating practices, the following measures will be implemented into well de sign, drilling and completion operations.

 BOP Certification, BOP Drills, Pit Dril l’s and all other required BSEE testing requirements,

 Current Well Control Certification for all Drilling and Completion Rig Site Supervisors,

 Taking Slow Pump Rate measurements during all open hole operations and critical cased hole operations,

 Updating Kill Sheets during each tour and posting the same on the rig floor,

 Maintain a current BOP to RKB spaceout chart,

 Monitoring wellbore fill-ups and displacements during trips, by the Well Site Supervisor,

 Maintain the necessary circulating swages, TI W Valves and IBOP on the rig floor at all times during operations and function te st these valves during each tour. The utilization of Pre-Job Safety meetings will continue to be implemented prior to each operation with all of the rig crews. These are intended to create a behavior based safety program and promote an atmosphere within the Apache and rig crew interface, such that a “Stop the Job” mentality is promoted across the rig contractor’s crew, empowering every crew member to question the safety of each operation.Apache Deepwater LLC Page B

‐ 7 Joint Initial Exploration Plan April 25, 2013 Mississippi Canyon Blocks 554/555 (OCS

‐ G 34444/34445) 

### Early well control intervention In the event of a blowout situation, due to fa iled BOP equipment and uncontrolled flow at the seafloor or at surface, assuming all other surface controlled actuation measures have failed or are inaccessible, a ROV will fly into position at the BOP subsea actuation panel and actuate the shear ram or pipe rams to establish containment. If the riser system and rig have been compromised, then debris removal will be initiated to obtain clear access to the BOP. A Capping Stack will be employed to achieve successful containment of the well. Once containment is established and wellbore pressure testing and assessment is completed by Apache and Well Control Specialist, we ll kill operations can be initiated through the existing wellbore.

Well control engineering services Apache will have service agreements in pla ce with Wild Well Control and Boots and Coots International Well Control prior to commencement of well operations. In the event of a blowout situation, these companies will be contacted to assist in the detailed design and implementation of well control and/or relief well operations.

Additional prevention & mitigation techniques Pursuant to wellbore cementing and zonal isolat ion techniques, all cementing operations will be modeled and designed under the gu idelines set forth in API Recommended Practice 65 Part 1 & 2. Operations will be dictated by the rules and requirements set forth in Federal Regulations, under the wellbore cementing requirements.
API Standard 53 for Blowout Prevention E quipment Systems for Drilling Wells and Recommended Practice 16Q for Marine Drilling Ri sers will be used as the guidelines for installation, testing and mainte nance of the surface and subsea Marine Risers and BOP systems. The purpose of these recommended practices is to provide information that can serve as a guide for installation and testing of blowout preven tion systems Apache has contracted for floating marine drilling rigs. The goal of using these recommended practices is to assist Apache operations in promoting personnel safety, public safety, an d integrity of the drilling equi pment and preservation of the environment for floating marine drilling opera tions. These recommended practices help to facilitate the broad availability of prove n, sound engineering and operating practices. These practices are considered acceptable for accomplishing BOP and Marine Riser associated operations. However, equivalent alternative inst allations and practices may be utilized to accomplish the same objectives. When using these recommended practices or other alternatives, Apache will insure that operations comply with requirements of Federal Regulations.Apache Deepwater LLC Page C

‐ 1 Joint Initial Exploration Plan April 25, 2013 Mississippi Canyon Blocks 554/555 (OCS

‐ G 34444/34445) 

### SECTION C GEOLOGICAL AND GEOPHYSICAL INFORMATION (30 CFR 550.214 and 550.244)

A. GEOLOGICAL DESCRIPTION Proprietary Information

B. STRUCTURE CONTOUR MAPS Proprietary Information

C. INTERPRETED 3-D SEISMIC LINE Proprietary Information

D. GEOLOGICAL STRUCTURE CROSS SECTIONS Proprietary Information

E. SHALLOW HAZARDS A Shallow Hazard Survey was conducted over Mississippi Canyon Blocks 554/555 by Geoscience Earth & Marine Services, Inc. (G EMS). The Shallow Hazard Report is being submitted to the BOEM in conjunction with this plan.

F. SITE-SPECIFIC SHALLOW HAZARDS ASSESSMENT A Shallow Hazards Assessment was prepared for th e proposed surface locatio ns utilizing the 3-D seismic exploration data and is included as Attachment C-4.

G. HIGH-RESOLUTION SEISMIC LINES Proprietary Information

H. STRATIGRAPHIC COLUMN Proprietary Information

I. TIME VS DEPTH TABLES Proprietary Information**10615 Shadow Wood Drive, Suite 200 Houston, Texas 77043**  **713.468.1410[o] 713.468.1438 [f]**

**www.gemsinc.com**

**February 20, 2013 Project No. 0712-2117b**  **Apache Deepwater LLC 2000 W. Sam Houston Parkway South**  **Suite 1600 Houston, TX 77042** 

**Attention: Mr. John Worthen**



### Site Clearance Letter Proposed Wellsite MC555-A Block 555 (OCS-G-34445) Mississippi Canyon Area Gulf of Mexico

**Apache Deepwater LLC (Apache) contracted Geoscience Earth & Marine Services, Inc. ®**  **, (GEMS) to prepare a Site Clearance Letter for the proposed well location in Block 555 (OCS G-34445), Mississippi**  **Canyon (MC) Area. This letter addresses specific seafloor and subsurface geologic conditions around the proposed location (2,000 ft radius) to the limit of investigation, 4,812 ft below the mudline (bml).**  **Apache will drill the proposed MC555-A with a semi-submersible or dynamically positioned (DP) semi-submersible. The seabed conditions within an 11,500 ft mooring radius plus an additional 1,000 ft**  **buffer zone are discussed to satisfy seabed disturbance guidelines. Surface conditions are clear at the proposed wellsite; however, moorings or other seabed disturbance**  **activities need to avoid a potential shipwreck, possible unexploded ordnance sites, and potential sites for benthic communities. Sandy units with potential for shallow water flow occur at 649 ft bml (585 ft thick)**  **and 1,709 ft bml (588 ft thick). This letter provides the following details specific to the well location: available data, attachments**  **(accompanying the letter), Notice to Lessees (NTL) requirements, man-made features and archaeological assessment, wellsite conditions, anchoring considerations, and the conclusions and recommendations.** 


### Proposed Well Location and Available Data **The proposed MC555-A surface location lies along the western edge of MC 555 (Figure MC555-A-1). Apache provided the following coordinates:** 
Proposed Wellsite MC555-A Spheroid & Datum: Clarke 1866, NAD27 Projection: UTM Zone 16 North Line Reference Block Calls MC 555 **X: 1,109,157 ft Latitude: 28o 25’ 40.7505” N Inline 15070 357 ft FWL Y: 10,320,035 ft Longitude: 88o 39’ 11.9875” W Crossline 13840 7,645 ft FNL** 
**The details provided in this letter are based on the findings from a geohazard assessment performed by GEMS (GEMS, 2012). The report which was submitted to Apache in December, 2012 described the**  **geologic and archaeological conditions within the Guadalupe Prospect (in Blocks 554 and 555) and vicinity. Apache provided two sets of geophysical data for this assessment: a conventional,**  **3-D exploration seismic volume and a high-resolution Autonomous Underwater Vehicle (AUV) data. The detailed data specifications are provided in the main report (GEMS, 2012). Well logs and drilling**  **reports from the closest existing well (ExxonMobil #1 in MC 555) to the proposed location were also Proposed Wellsite MC555-A Clearance Letter** 

**Apache Deepwater LLC //**  **February 20, 2013**

**Geoscience Earth & Marine Services, Inc. ®** // 2 FORUM ENERGY TECHNOLOGIES, INC. **provided by Apache. Integrating these data allowed a thorough analysis of potential drilling hazards within the suprasalt stratigraphy at the proposed wellsite.** 



### Attachments **The page-size maps and accompanying illustrations were extracted from the available data provided by Apache. A maximum anchor radius of 11,500 ft and an additional 1,000 ft buffer zone are included on the**  **maps should Apache use a moored rig to drill. The figures embedded within the body text are also provided below.**  **Map No. MC555-A-1: Bathymetry Map Map No. MC555-A-2: Seafloor Features Map**  **Map No. MC555-A-3: Side-Scan Sonar Mosaic Map No. MC555-A-4: Geologic Features Map**  **Illustration MC555-A-1: Portions of Inline 15070 and Crossline 13840 Showing Conditions Beneath Proposed Wellsite MC555-A**  **Illustration MC555-A-2: Tophole Prognosis Chart, Proposed Wellsite MC555-A, Mississippi Canyon, Block 555**  **Illustration MC555-A-3: Potential for Benthic Communities Figure MC555-A-1: Regional Rendering of Mississippi Canyon Area, Gulf of Mexico**  **Figure MC555-A-2: Power Spectrum Analysis Curve, Proposed Wellsite MC555-A Figure MC555-A-3: Seafloor Conditions at the Proposed Wellsite**  **Figure MC555-A-4: Suprasalt Stratigraphy between the Proposed Wellsite and ExxonMobil #1**

Figure MC555-A-1 **. Regional Rendering of Mississippi Canyon Area, Gulf of Mexico** MC554-A MC555-A

MC555-B Grid North

MISSISSIPPI CANYON AREA

3 miles **Survey Area**
**AUV Survey Area**
**High-potential Archaeological Area**  **Chemosynthetic Area**

**Shallow Water flow Area**
**Ordnance Disposal Area Existing Platform** 
**Existing Well**
**Proposed Well Location Existing Pipeline/**  **Umbilical** MENSA Mass-wasting Pathway Erosional Remnants**Proposed Wellsite MC555-A Clearance Letter**

**Apache Deepwater LLC //**  **February 20, 2013**

**Geoscience Earth & Marine Services, Inc. ®** // 3 FORUM ENERGY TECHNOLOGIES, INC. 

### NTL Requirements **The following letter complies with the Bureau of Ocean Energy Management (BOEM) Notice to Lessees (NTL’s) 2008-G04, 2008-G05, and 2009-G40, (MMS, 2008a, b and 2010). The requirements set forth in**  **NTL 2005-G07 are applicable because the Federal lease block MC 555 is considered to be a high probability archaeological block (MMS, 2005 and BOEM, 2011). In compliance with NTL 2005-G07, the**  **required archaeological assessment was performed by GEMS and included as an appendix in the main report (GEMS, 2012).**  **According to NTL 2008-G05 (MMS, 2008b), 3-D seismic reflection data may be used for shallow hazard assessments with approval from the BOEM, Gulf of Mexico Region. A power spectrum analysis was**  **conducted from the 3-D seismic data cube provided by Apache to illustrate the data parameters (Figure MC555-A-2). The power spectrum curve was generated within a 500 ft radius of the intersection**  **of the inline and crossline at the proposed wellsite. We converted the amplitude vs. frequency spectrum, generated by the SMT software, to power vs. frequency by squaring the amplitude values as described by**  **J. A. Coffeen, 1978.**

Figure MC555-A-2

**. Power Spectrum Analysis Curve, Proposed Wellsite MC555-A** 


### Man-Made Features and Archaeological Assessment **The surface location is clear of any wells, pipelines, or platforms within a 2,000 ft radius from the proposed wellsite. The closest existing well (ExxonMobil #1) is located approximately 1.3 miles southeast**  **of the proposed wellsite location in MC 555 (Map MC555-A-1). The well was an exploratory well and is currently temporarily abandoned.**  **GEMS delineated 23 unidentified side-scan sonar contacts in the digital data within 12,500 ft (11,500 ft maximum anchor radius plus 1,000 ft buffer) of the proposed MC555-A (Maps MC555-A-2 and 555-A-3).**  **Side-Scan Sonar Contact Number 54 appears to represent a potential shipwreck. The contact is located approximately 2.2 miles southeast of the proposed wellsite and a 1,000 ft archaeological avoidance is**  **recommended around the contact. No known shipwrecks or objects exist within the area of potential effect for the proposed well location.**  **0 0.1**  **0.2 0.3**  **0.4 0.5**  **0.6 0.7**  **0.8 0.9**  **1**

**0 10 20 30 40 50 60 70 80 90 100 110 120**Power (Amp2)

Frequency (Hz) POWER SPECTRUM**Proposed Wellsite MC555-A Clearance Letter**

**Apache Deepwater LLC //**  **February 20, 2013**

**Geoscience Earth & Marine Services, Inc. ®** // 4 FORUM ENERGY TECHNOLOGIES, INC. **None of the other 22 contacts appear to represent cultural resources. Several of the unidentified sonar contacts form part of a northeast-southwest trending debris trail in MC Blocks 554 and 598. The debris**  **likely represents unexploded ordnance because the designated historic ordnance disposal area lies west of the Guadalupe prospect (Figure MC554-A-1). The side-scan sonar contacts within 12,500 ft of the**  **proposed wellsite that form part of the debris trail are Side-Scan Sonar Contact Numbers 43, 45-46, 48, and 76-78. None of these unidentified side-scan sonar contacts are recommended for archeological**  **avoidance or investigation, but Apache should use caution when working near the debris trail because of the risk for contact with unexploded ordnance. Other similar contacts along the path of the debris trail**  **were identified in the side-scan sonar data, but were not retained in the final contact list. Since these contacts were not visible in two or more overlapping swaths of data, it was not possible to verify if the**  **contacts represented actual debris or noise in the sonar record. A 100 ft shallow hazard avoidance is recommended for the remaining 22 side-scan sonar contacts.** 

Table 1. Sonar Contacts Located Within 12,500 ft of MC555-A

No. Area Block Length (ft) Width

(ft) Height

(ft) Shape X NAD27 (ft) Y

NAD27 (ft) Avoidance

Radius (ft)

**19 MC 511 5.44 1.86 0.00 Linear 1112591.97 10329220.90 100 20 MC 511 14.68 7.23 1.75 Irregular 1112902.20 10329423.85 100**  **21 MC 511 35.69 13.33 1.24 Irregular 1112951.32 10329320.37 100 42 MC 554 12.42 6.58 0.00 Linear 1100325.29 10313357.68 100**  **43 MC 554 10.12 2.37 0.00 Linear 1101971.94 10312550.76 100 44 MC 554 16.49 7.46 0.00 Irregular 1102351.14 10324394.30 100**  **45 MC 554 26.64 9.48 0.00 Irregular 1102457.87 10313328.31 100 46 MC 554 16.93 3.61 0.00 Linear 1102620.96 10313548.00 100**  **47 MC 554 13.22 2.94 0.00 Linear 1102642.15 10327125.63 100 48 MC 554 12.65 4.52 0.00 Linear 1103307.63 10315340.61 100**  **49 MC 554 11.29 3.64 0.00 Linear 1104028.27 10311991.31 100 50 MC 555 11.52 4.74 0.00 Irregular 1112644.89 10312564.17 100**  **51 MC 555 10.50 8.70 0.00 Linear 1113273.53 10315889.23 100 52 MC 555 11.52 2.48 0.00 Linear 1116727.29 10314034.61 100**  **53 MC 555 20.24 5.06 0.00 Linear 1118118.76 10326028.12 100 54**  **MC 555**  **42.49 24.57**  **0.00 Irregular**  **1119186.80 10314174.41**  **1,000 76 MC 598 15.20 3.37 0.00 Linear 1101123.39 10311196.89 100**  **77 MC 598 10.12 2.17 0.00 Linear 1101235.39 10311328.45 100 78 MC 598 9.00 2.18 0.00 Linear 1101247.04 10311266.08 100**  **82 MC 598 10.86 2.08 0.00 Linear 1105782.24 10308511.16 100 83 MC 598 10.86 2.65 0.00 Linear 1106972.13 10311235.93 100**  **86 MC 599 17.16 18.29 0.00 Irregular 1110651.55 10309177.14 100 89 MC 599 15.74 5.94 0.00 Linear 1113261.85 10308889.05 100**  ***Blue indicates a recommended archaeological avoidance.**



### Wellsite Conditions **The proposed surface location is clear of any constraining seafloor geologic conditions as defined by the available geophysical data. MC555-A is expected to intersect a buried fault. The potential for encountering**  **significant amounts of shallow gas is low. However, there is a moderate potential for encountering shallow water flow within possible overpressured sands.**  Water Depth and Seafloor Conditions **The water depth at the proposed surface location is approximately -4,651 ft and the seafloor slopes southeast at less than 2° (Map MC555-A-1). Side-scan sonar data show that the seabed in the vicinity of**  **the proposed wellsite is primarily characterized by uniform low reflectivity (Map MC555-A-3). The low reflectivity is likely associated with very soft clays.** **Proposed Wellsite MC555-A Clearance Letter**

**Apache Deepwater LLC //**  **February 20, 2013**

**Geoscience Earth & Marine Services, Inc. ®** // 5 FORUM ENERGY TECHNOLOGIES, INC. **The proposed wellsite MC555-A is located along a relatively shallow mass-wasting pathway trending northwest-southeast across the Survey Area (Figure MC555-A-1 and Map MC555-A-2). The hummocky**  **topography within the vicinity of the proposed location represents the seafloor expression of buried slumps. The slumps are buried by more than 100 ft of strata (Figure MC555-A-3, GEMS, 2012). Mound-like**  **features in the same area are associated with rafted blocks within the mass-transport deposits (MTD) matrix and are not hydrocarbon related (GEMS, 2012). A drainage feature (gully) located approximately 348 ft to**  **the northwest suggests low-level sediment transport activities in the recent geologic past (> 10,000 yrs), (Figure MC555-A-1).** 

Figure MC555-A-3 **. Seafloor Conditions at the Proposed Wellsite** Deepwater Benthic Communities **BOEM and BSEE did not designate Federal lease Block MC 555 as having high-density deepwater benthic communities (MMS, 2010). There are no apparent geophysical indicators at the seafloor or at**  **depth that would suggest conditions capable of supporting significant deepwater benthic communities within 2,000 ft of the proposed wellsite (Maps MC555-A-2 and 555-A-3).**  Stratigraphy **Stratigraphic conditions are shown on Illustrations MC555-A-1 and 555-A-2. The lithology at the proposed wellsite was inferred by integrating the seismic facies with the well log response at the existing**  **well, ExxonMobil #1. Generally, the suprasalt seismic facies were correlated across both locations; however, the sand-prone channel system observed within Unit 4 at ExxonMobil #1 is absent at the**  **proposed location (Figure MC555-A-4). The sediments below the seafloor to the limit of investigation (4,812 ft bml or -9,463 ft bsl) consist primarily of hemipelagic clays, muddy- to sand-prone turbidites,**  **slope fan deposits, and mass-transport deposits. The shallow stratigraphy (Seafloor to Horizon 10, Un**  **it 1) is interpreted to be hemipelagic clay- to silt-rich sediments down to approximately 200 ft bml. The sediment units between Horizon 10 and Horizon 30**  **(Units 2 and 3) are dominated by mass-transport deposits (MTD) with intermittent silty- to sandy turbidites to approximately 1,234 ft bml. Sand-prone erosional remnants from older strata are possible within the**  **MTD matrix. Unit 3 is associated with a regional basin-floor fan system known as the “Blue Unit” (GEMS, 2012). The low gamma ray log response (inferring sand) at ExxonMobil #1 suggests that there is a high** 

Portion of AUV Line 131 **Seafloor expression of rafted block** 

**500 ft**

**Assumed velocity: 5,000 ft/sec** W E**Two-way travel time (secs) Horizontal**  **Distance (ft)** Proposed Wellsite MC555-A

**Weakly stratified** INDEX MAP

AUV Line 131 **Seafloor expression of**  **rafted blocks** Grid North

MC 554

**1,000 ft Buried slump** 

MC555-A

MC 555

**Circle represents 2,000 ft radius around**  **proposed wellsite Gully** 

**10 ft Mound-like features at the seabed**  **represent the seafloor expression of rafted blocks within buried slumps.**  **The slumps are buried by more than 100 ftof strata.**  **The lack of direct hydrocarbon indicators (DHI) at these sites confirm**  **that the features are not hydrocarbon related. See the main report for more**  **details (GEMS, 2012). MC 554 MC 555** 

Seafloor Rendering **Amorphous layer**

**W ell-layered**  **unit**

**Shallow strata comprises of hemipelagic clay- to silt-rich**  **sediments. Proposed Wellsite MC555-A Clearance Letter** 

**Apache Deepwater LLC //**  **February 20, 2013**

**Geoscience Earth & Marine Services, Inc. ®** // 6 FORUM ENERGY TECHNOLOGIES, INC. **potential for sandy turbidites within the Blue Unit between 649 ft bml and 1,234 ft bml (Figure MC555-A-4).**  **Remnants of a sand-prone slope fan system occur in the middle portion of Unit 4 (Horizon 30 to Horizon 40). A vertical borehole at the proposed location will intersect the slope fan sediments from**  **approximately 1,709 ft bml to 2,297 ft bml. The upper portion of the strata (between 1,234 ft bml to 1,709 ft bml) comprises of mud-dominated turbidites, while the lower portion (between 2,297 ft bml to 2,620 ft**  **bml) comprises of mud-dominated rotated slide blocks and silt- to sand-prone turbidites. The underlying strata, Unit 5 (Horizon 40 to the limit of investigation) comprises of muddy- to sandy turbidites and**  **possibly MTDs. Thick, continuous sand layers are possible within this sediment unit (between 2,620 ft bml and 4,812 ft bml), Figure MC555-A-4.** 

Figure MC555-A-4 **. Suprasalt Stratigraphy between the Proposed Wellsite and ExxonMobil #1**
Faults **No seafloor faults will be encountered at the proposed wellsite location (Map MC555-A-2). However, a vertical wellbore at proposed wellsite MC555-A will penetrate a buried fault at approximately 2,297 ft bml**  **(-6,948 ft bsl), Illustrations MC555-A-1 and 555-A-2. The fault is downthrown northwest towards the wellbore and is buried by up to 1,600 ft of sediments.** 
Shallow Gas and Shallow Water Flow **The scout tickets from ExxonMobil # 1 did not report any shallow geohazard conditions related to shallow water flow and/or shallow gas. As a result, significant shallow gas is not expected at the proposed**  **wellsite; however, a moderate potential for shallow water flow is possible within the identified sand prone sequences (Illustration MC555-A-2).**  INDEX MAP

Seafloor Rendering Grid North

MC 554

**2,000 ft** MC555-A

**Circle represents 2,000 ft radius around proposed**  **wellsite** ExxonMobil #1

MC 555

MC 599**Two-way travel time (secs) Horizontal**  **Distance (ft)** Proposed Wellsite MC555-A ExxonMobil #1

**MC 599 MC 555**  **MC 554**

Arbitrary Line A-A` **5,000 ft** NW SE **Seafloor**

**H orizon 10** 

**Horizon 20**

**Horizon 30**

**Limit of Investigation**  GR R GR - Gamma Ray R - Resistivity

**Generally, the suprasalt stratigraphy at the**

**existing well location (ExxonMobil #1) and the proposed wellsite MC555-A is similar. The**  **main difference observed is within Unit 4 where only remnants of the slope fan system**  **exist at the proposed location. The 22” casing got stuck and was later jarred**  **free at ExxonMobil #1. The casing was stuck in possibly clay-prone sediments within the**  **channel system in Unit 4.** Relative Amplitude **High Low**  **UNIT 1**

**UNIT 2**

**UNIT 3**

**UNIT 4**

**UNIT 5 Horizon 40**  **Channel** Blue Unit

22” casing stuck**Proposed Wellsite MC555-A Clearance Letter**

**Apache Deepwater LLC //**  **February 20, 2013**

**Geoscience Earth & Marine Services, Inc. ®** // 7 FORUM ENERGY TECHNOLOGIES, INC. Shallow Gas. **There are no apparent subsurface high-amplitude anomalies directly below the proposed location (Map MC555-A-4). Slightly elevated amplitude responses near the buried fault (within Unit 4)**  **suggest minor amounts of biogenic gas accumulation within the unit (Illustration MC555-A-2). The amplitudes are however, buried by up to 1,700 ft of sediments and there is no geophysical evidence**  **that suggests fluid migration from depth to shallower sediments. There is a low potential for encountering significant accumulation of shallow gas within these sand-prone slope fan sediments as well as within**  **possible sand layers between 649 ft bml to the limit of investigation (4,812 ft bml). The potential for encountering shallow gas is considered negligible in the clay-prone unit between the Seafloor and**  **649 ft bml.**
Shallow Water Flow. **T here is a moderate potential for encountering overpressured sands within the**  **Blue Unit, Unit 3 (649 ft bml to 1,234 ft bml) and the underlying slope fan system (1,709 ft bml to 2,297 ft bml), Illustration MC555-A-2. Although, numerous wells in the Mississippi Canyon Area have**  **experienced water flow within the Blue Unit, no such occurrence was reported at ExxonMobil #1. Potential overpressures may have been mitigated while drilling the well, and hence not reported.**  **A low potential for shallow water flow is interpreted between 1,234 ft bml to 1,709 ft bml and beneath 2,297 ft bml. The shallow, clay-rich sediments (Seafloor to 649 ft bml) are considered to have a negligible**  **potential for shallow water flow.** 

### Anchoring Considerations **The 11,500 ft radius outlined on the accompanying maps represents the area of potential effect for anchoring. An additional 1,000 ft buffer zone is also included. The following discussions address the**  **seafloor conditions related to anchoring considerations within the total 12,500 ft radius.** Water Depth and Seafloor Conditions **Water depths within the potential mooring area range from about -4,453 ft to -4,868 ft (Map MC555-A-1). The seafloor slopes southeast with shallow water depths in the western portion of the mooring radius.**  **Seafloor gradients within the mooring radius range from nearly flat to approximately 42° (GEMS, 2012). Most of the seafloor has low gradients (less than 3°).**  **Irregular seafloor morphology within the potential mooring area is associated with erosion-related features (e.g. gullies and erosional scarps) and seep-related features (e.g. mounds and pockmarks),**  **Map MC555-A-2. The hummocky seafloor across most of the remaining area represents shallow buried slumps and the mound-like features within the slumps represent buried rafted blocks (Figure MC555-A-3).**  **Seafloor slopes associated with the erosion-related and seep-related features range from 5° to 13° (GEMS, 2012).**  **Seafloor faulting is located in the northeastern portion of the radius in central MC 555. The faults trend northeast-southwest, are downthrown mainly to the northeast, and bound the expulsion features.**  **Seafloor offsets associated with the faults are up 50 ft with associated slopes reaching 42°.** Deepwater Benthic Communities **The expulsion features that exhibit high backscatter reflectivity and “rocky” topography on sonar data are likely associated with carbonate hard grounds (conditions conducive for benthic communities), Map**  **MC555-A-3 and Illustration MC555-A-3. These expulsion features have a high potential for supporting densely populated benthic communities and are shown as orange polygons on Map MC555-A-2.**  **The features lacking irregular topography but still exhibit high backscatter and sonar reflectivity represent limited hard ground areas. These sites have a lower potential for supporting seep communities and are**  **shown as green polygons on Map MC555-A-2. BOEM requires at least a 250 ft buffer around potential benthic community sites for all proposed seafloor**  **disturbances (including those caused by anchors and anchor chains), MMS, 2010. However, if seafloor disturbances occur within 500 ft of these sites, Apache is required to submit an as-placed anchor plat to**  **BOEM. We recommend conducting an ROV investigation to confirm or deny the existence of deepwater Proposed Wellsite MC555-A Clearance Letter** 

**Apache Deepwater LLC //**  **February 20, 2013**

**Geoscience Earth & Marine Services, Inc. ®** // 8 FORUM ENERGY TECHNOLOGIES, INC. **benthic communities at the potential hard grounds if these areas occur near the proposed anchors or anchor chains.** 



### Conclusions and Recommendations **We appreciate the opportunity to be of service to Apache and look forward to working with Apache on future projects. The conclusions and recommendations from this assessment are as follows:** 
Wellsite Conditions **No major seafloor hazards or constraints are defined by the available data within 2,000 ft radius of the proposed location. Caution and possible mitigation is recommended when encountering potential**  **overpressured sands between 649 ft bml to 1,234 ft bml, and 1,709 ft bml to 2,297 ft bml.**
Anchor Maximum Radius Conditions **The potential seafloor constraints within the mooring radius include possible hard grounds that could support benthic communities, a potential shipwreck, and possible unexploded ordnance sites.**  **A minimum of a 250 ft radius is recommended around the potential benthic communities’ sites. Other recommendations include, a 1,000 ft archaeological avoidance around Side-Scan Sonar Contact Number**  **54, and a 100 ft shallow hazard avoidance for the remaining 22 side-scan sonar contacts. Care should be taken near the debris trail of potential unexploded ordnance in MC 554 and 598. All operations must**  **cease and BOEM notified within 48 hours should any potentially historic materials such as textiles, wood, ceramics, or other items be uncovered during operations in the area.** 

**Sincerely,**
GEOSCIENCE EARTH & MARINE SERVICES, INC. ®

**Oluwayomi Oyedele Daniel Lanier**  **Geoscientist Vice President-Geosciences** 

**Erin Williams Janes Project Manager/Senior Geoscientist** 
**Attachments (4 Maps and 3 Illustrations)**
**Distribution: Mr. John Worthen, Apache Deepwater LLC (3 copies)** 

REFERENCES **Bureau of Ocean Energy Management, 2013, ASCII Data Files, published on the BOEM Gulf of Mexico Region Homepage, <http://www.gomr.boem.gov/homepg/pubinfo/freeasci/freedesc.html>, accessed January, 2013.**  **Bureau of Ocean Energy Management, 2012, Seismic Water Bottom Anomalies Map Gallery, published on the BOEM Homepage, <http://www.boem.gov/Oil-and-Gas-Energy-Program/Mapping-and-Data/Map-Gallery/Seismic**  **Water-Bottom-Anomalies-Map-Gallery.aspx>, accessed November, 2012. Bureau of Ocean Energy Management, 2011, Notice to lessees and operators (NTL) of federal oil and gas leases**  **and pipeline right-of-way (ROW) holders on the outer continental shelf (OCS), Revisions to the list of OCS lease Proposed Wellsite MC555-A Clearance Letter** 

**Apache Deepwater LLC //**  **February 20, 2013**

**Geoscience Earth & Marine Services, Inc. ®** // 9 FORUM ENERGY TECHNOLOGIES, INC. **blocks requiring archaeological resource surveys and reports: U. S. Department of the Interior, Bureau of Ocean Energy Management, Bureau of Safety and Environmental Enforcement Gulf of Mexico Region (GOMR), NTL 2011-**  **JOINT-G01. Effective Date December 29, 2011. Coffeen, J. A., 1978, Seismic Exploration Fundamentals: Tulsa, the Petroleum Publishing Co., p. 125.**  **Geoscience Earth & Marine Services, Inc. ®**  **(GEMS), 2012, Geohazard assessment, Guadalupe Prospect, blocks 554 and 555, Mississippi Canyon Area, Gulf of Mexico, Project No. 0712-2117b.**  **Minerals Management Service, 2005, Notice to lessees and operators of federal oil, gas, and sulphur leases and pipeline right-of-way holders in the outer continental shelf, Gulf of Mexico OCS region, Archaeological resource**  **surveys and reports: U. S. Department of the Interior, Minerals Management Service, Gulf of Mexico, NTL 2005-G07. Minerals Management Service, 2008a, Notice to lessees and operators of federal oil, gas, and sulphur leases and**  **pipeline right-of-way holders in the outer continental shelf, Gulf of Mexico OCS region, information requirements for exploration plans and development operations coordination documents: U. S. Department of the Interior, Minerals**  **Management Service, Gulf of Mexico, NTL 2008-G04. Minerals Management Service, 2008b, Notice to lessees and operators of federal oil, gas, and sulphur leases and**  **pipeline right-of-way holders in the outer continental shelf, Gulf of Mexico OCS region, shallow hazards requirements: U. S. Department of the Interior, Minerals Management Service, Gulf of Mexico, NTL 2008-G05.**  **Minerals Management Service, 2010, Notice to lessees and operators of federal oil and gas leases in the outer continental shelf, Gulf of Mexico OCS region, deepwater benthic communities: U. S. Department of the Interior,**  **Minerals Management Service, Gulf of Mexico, NTL 2009-G40. Effective Date January 27, 2010.**