UNITED STATES GOVERNMENT MEMORANDUM

To: Public Information (MS 5030)

Plans Section, Office of Field 

Operations (MS 5231)

Public Information copy of Exploration Plan

Control # - R-05208

Type - Revised Exploration Plan

Lease(s) - OCS-G24062 Block - 253 Mississippi Canyon Area

OCS-G32303 Block - 208 Mississippi Canyon Area

Operator - LLOG Exploration Offshore, L.L.C.

Wells A through E

SEMISUBMERSIBLE

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.

Chiquita Hill

Plan Coordinator

Description -

Rig Type -

Subject:

From:

September 22, 2011

LLOG EXPLORATION OFFSHORE, L.L.C. 

1001 Ochsner Boulevard, Suite 200 

Covington, Louisiana 70433 

REVISED EXPLORATION PLAN 

OCS-G-32303 & OCS-G-24062 

MISSISSIPPI CANYON BLOCKS 208/253 

PREPARED BY: 

Kathy Gowland 

Regulatory Specialist 

985-801-4300 (Main) 

985-801-4317 (Direct) 

kathygo@llog.com
LLOG EXPLORATION OFFSHORE, L.L.C.

REVISED EXPLORATION PLAN 

OCS-G-32303 & 24062 Leases 

Mississippi Canyon Blocks 208 & 253 

APPENDIX A Plan Contents 

APPENDIX B General Information 

APPENDIX C Geological, Geophysical Information 

 

APPENDIX D H2S Information 

APPENDIX E Biological, Physical and Socioeconomic Information 

APPENDIX F Waste and Discharge Information 

APPENDIX G Air Emissions Information 

 

APPENDIX H Oil Spill Information 

APPENDIX I Environmental Monitoring Information 

APPENDIX J Lease Stipulation Information 

APPENDIX K Environmental Mitigation Measures Information 

APPENDIX L Related Facilities and Operations Information 

APPENDIX M Support Vessels and Aircraft Information 

APPENDIX N Onshore Support Facilities Information 

APPENDIX O Coastal Zone Management Act (CZMA) Information 

APPENDIX P Environmental Impact Analysis 

APPENDIX Q Administrative Information 
Mississippi Canyon Block 253 (OCS-G 24062) 7/7/2011 

Mississippi Canyon Block 208 (OCS-G-32303) 

Revised Exploration Plan 1

 

APPENDIX A 

PLAN CONTENTS

(30 CFR Part 250.211 and 250.241) 

A. Plan information 

In accordance with 30 CFR 250.211 and 250.241(a),and NTL No. 2008-G04 

and NTL 2010-N06, LLOG Exploration Offshore, LLC proposes to revise our 

currently approved Exploration Plan (Control No. N-09406) for the drilling, 

completion and testing and installation of subsea wellhead and/or manifold for 

proposed locations for Lease OCS-G-24062, Mississippi Canyon Block 253, 

Wells A and B and Lease OCS-G-32303, Mississippi Canyon Block 208, 

Wells C, D and E. 

Included as Attachment A is Form MMS 137 “OCS Plan Information Form”. 

. 

 B. Location 

Attachment B – Well Location Plat - No change – Refer to Initial EP for MC 

253, OCS-G-24062 Lease and MC 208, OCS-G-32303, Control No. N-09406 

approved on October 22, 2009.

 Attachment C – Bathymetry Map – Seafloor disturbance area with anchor 

 Radius - Revised 

C. Safety & Pollution Features 

Safety features on the semi-submersible will include well control, pollution 

prevention, welding procedure, and blowout prevention equipment as described 

in Title 30 CFR Part 250, Subparts C, D, E, G & O; and as further clarified by 

Notices to Lessees, U.S. Environmental Protection Agency and the U. S. Coast 

Guard. The appropriate life rafts, life jackets, ring buoys, etc., as prescribed by 

the U. S. Coast Guard will be maintained on the facility at all times. 

No change – Refer to Initial EP for MC 253, OCS-G-24062 Lease and MC 

208, OCS-G-32303, Control No. N-09406 approved on October 22, 2009.

D. Storage Tanks and Vessels 

The following table details the storage tanks and/or production vessels that will 

store oil (capacity greater than 25 barrels) and be used to support the proposed 

activities (MODU, barges, platform, etc.): 
Mississippi Canyon Block 253 (OCS-G 24062) 6/16/2011 

Mississippi Canyon Block 208 (OCS-G-32303) 

Revised Exploration Plan 2

 

Type of 

Storage Tank 

Type of 

Facility 

Tank Capacity 

(bbls) 

Number of 

tanks 

Total Capacity 

(bbls) 

Fluid Gravity 

(API) 

Fuel Oil 

(Marine Diesel) 

SemiSubmersible 95.24 2 190.5 No. 2 Diesel 

 2917.8 4 11,671.2 

Total 11,861.7 

E. Pollution Prevention Measures 

This section of the plan is not applicable to the proposed operations. 

No change – Refer to Initial EP for MC 253, OCS-G-24062 Lease and MC 

208, OCS-G-32303, Control No. N-09406 approved on October 22, 2009.

F. Additional measures: 

No additional measures are proposed. 

No change – Refer to Initial EP for MC 253, OCS-G-24062 Lease and MC 

208, CS-G-32303, Control No. N-09406 approved on October 22, 2009. 

U.S. Department of the Interior OMB Control Number: 1010-0151

Minerals Management Service OMB Approval Expires: 12/31/2011

OCS PLAN INFORMATION FORM 

General Information 

Type of OCS Plan: Exploration Plan (EP) Development Operations Coordination Document (DOCD) 

Company Name: MMS 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 MMS-designated high-probability archaeological area? Yes No 

Have all of the surface locations of your proposed activities been previously reviewed and approved by MMS? 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) 

 

MMS FORM MMS-137 (December 2008 - Supersedes all previous editions of form MMS-137 which may not be used.) Page 1 of 2

2

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): Subsea Completion 

Anchor Radius (if applicable) in feet: Yes No 

Surface Location Bottom-Hole Location (For Wells) 

Lease No. OCS OCS 

Area Name 

Block No. 

Blockline 

Departures 

(in feet)

N/S Departure: F____ L N/S Departure: F____ L 

 E/W Departure: F____ L E/W Departure: F____ L 

Lambert X-Y 

coordinates 

X: X: 

 Y: Y: 

Latitude/ 

Longitude

Latitude Latitude 

Longitude Longitude 

TVD (Feet): MD (Feet): Water Depth (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 = 

Paperwork Reduction Act of 1995 Statement: The Paperwork Reduction Act of 1995 (44 U.S.C. Chapter 35) requires us 

to inform you that MMS collects this information as part of an applicant’s Exploration Plan or Development Operations 

Coordination Document submitted for MMS approval. We use the information to facilitate our review and data entry for 

OCS plans. We will protect proprietary data according to the Freedom of Information Act and 30 CFR 250.197. An 

agency may not conduct or sponsor, and a person is not required to respond to, a collection of information unless it displays 

a currently valid Office of Management and Budget Control Number. The use of this form is voluntary. The public 

reporting burden for this form is included in the burden for preparing Exploration Plans and Development Operations 

Coordination Documents. We estimate that burden to average 600 hours per response, or 640 with an accompanying EP 

(1,000 hours in AKOCSR), or 690 (1,700 in AKOCSR) with an accompanying DPP or DOCD, including the time for 

reviewing instructions, gathering and maintaining data, and completing and reviewing the forms associated with subpart B. 

Direct comments regarding the burden estimate or any other aspect of this form to the Information Collection Clearance 

Officer, Mail Stop 5438, Minerals Management Service, 1849 C Street, NW., Washington, DC 20240.

 

MMS FORM MMS-137 (December 2008 - Supersedes all previous editions of form MMS-137 which may not be used.) Page 2 of 2







±

3® 3

3

3

3® 3

3

3

-5000

-4900

-5100

-4800

-5200

-4700

-4600

-4500

-4400

-4900 -4800

-4900

-4800

88°19'0"W88°20'0"W88°21'0"W

28°45'0"N

28°44'0"N

28°43'0"N

1,205,0001,210,0001,215,000

10,425,000

10,430,000

10,435,000

10,440,000

0 500 1,000 2,000 Feet

0 125 250 500 Meters

Chart scale 1" = 2,000'

Bathymetry Plat Figure 10

Proposed MC253-A

Easting: 1,204,584ft

Northing: 10,431,637ft

Latitude: 28° 44' 17.68"

Longitude: 88° 21' 37.34"

Proposed MC253-B

Easting: 1,204,436ft

Northing: 10,434,800ft

Latitude: 28° 44' 48.98"

Longitude: 88° 21' 39.41"

MISSISSIPPI CANYON BLOCK 253 (OCS-G24062)
±

3® 3

3

3

3® 3

3

3 3® 3

3

3

3® 

3

-4600

-4500

-4400

-4300

-4200

-4100

-4700

-4000

-3900

-3800

-3700

-4800

88°22'0"W88°23'0"W88°24'0"W

28°48'0"N

28°47'0"N

28°46'0"N

1,190,0001,195,0001,200,000

10,440,000

10,445,000

10,450,000

10,455,000

0 500 1,000 2,000 Feet

0 125 250 500 Meters

Chart scale 1" = 2,000'

Bathymetry Plat Figure 10

Proposed MC208-C

Easting: 1,202,630ft

Northing: 10,439,071

Latitude: 28° 45' 31.07"

Longitude: 88° 22' 0.25"

Proposed MC208-D

Easting: 1,200,850ft

Northing: 10,439,116ft

Latitude 28° 45' 31.31"

Longitude: 88° 22' 20.26"

Proposed MC208-E

Easting: 1,203,299ft

Northing: 10,446,834ft

Latitude: 28° 46' 48.01"

Longitude: 88° 21' 53.74"

MISSISSIPPI CANYON BLOCK 208 (OCS-G32303)
Mississippi Canyon Block 253 (OCS-G 24062) 6/21/2011 

Mississippi Canyon Block 208 (OCS-G-32303) 

Revised Exploration Plan 3

 

APPENDIX B 

GENERAL INFORMATION

(30 CFR Part 250.213 and 250.243) 

A. Applications and Permits

There are no Federal/State applications to be submitted for the activities provided 

for in this Plan (exclusive to BOEMRE permit applications and general permits 

issued by the EPA and COE) 

Application/Permit Issuing Agency Status 

N/A 

 

B. Drilling Fluids

Type of Drilling Fluid Estimated Volume of Drilling Fluid 

to be used per Well 

Water Based (seawater, freshwater, barite) 63,745 bbls 

Oil –based (diesel, mineral oil) N/A 

Synthetic-based (internal olefin, ester) 6,750 bbls 

C. New Or Unusual Technology

LLOG does not propose using any new and/or unusual technology for the 

operations proposed this Revised Plan. 

No change – Refer to Initial EP for MC 253, OCS-G-24062 Lease and MC 

208, OCS-G-32303, Control No. N-09406 approved on October 22, 2009.

D. Bonding Statement

The bond requirements for the activities and facilities proposed in this Revised EP 

are satisfied by an area wide bond, furnished and maintained according to 30 CFR 

Part 256; subpart I; NTL No. 2006-G16, “Guidelines for General Lease Surety 

Bonds,” and additional security under 30 CFR 256.43(d) and National NTL No. 

2003-N06 “Supplemental Bonding Procedures.” 

No change – Refer to Initial EP for MC 253, OCS-G-24062 Lease and MC 

208, OCS-G-32303, Control No. N-09406 approved on October 22, 2009.
Mississippi Canyon Block 253 (OCS-G 24062) 6/16/2011 

Mississippi Canyon Block 208 (OCS-G-32303) 

Revised Exploration Plan 4

 

E. Oil Spill Responsibility (OSFR)

LLOG Exploration Offshore, L.L.C (MMS Co. No. 02058) will demonstrate oil 

spill financial responsibility for the facilities proposed in this Revised EP 

according to 30 CFR Part 253, and NTL 99-N01, “Guidelines for Oil Spill 

Financial Responsibility for Covered Facilities.” 

No change – Refer to Initial EP for MC 253, OCS-G-24062 Lease and MC 

208, OCS-G-32303, Control No. N-09406 approved on October 22, 2009.

F. Deepwater Well Control Statement

LLOG Exploration Offshore, L.L.C. (MMS Co. No. 02058) has the financial 

capability to drill a relief well and conduct other emergency well control 

operations. 

No change – Refer to Initial EP for MC 253, OCS-G-24062 Lease and MC 

208, OCS-G-32303, Control No. N-09406 approved on October 22, 2009.

G. Blowout Scenario

See the following Blowout Scenario including Site Specific Proposed Relief Well 

and Intervention Planning and Relief Well Response Time Estimate. 
BLOWOUT SCENARIO 

 MC 208-253 

Created by: S.L. Stegeman 

Last Revised: 7/13/2011 

Page 1 of 8 

Confidential

 1 

BLOWOUT SCENARIO 

Pursuant with 30 CFR 250.213(g), 250.219, 250,250 and NTL 2010-N06 the following attachment 

provides a blowout scenario description, information regarding any oil spill, WCD results and assumptions 

of potential spill and additional measures taken to firstly enhance the ability to prevent a blowout and 

secondly to manage a blowout scenario if it occurred. 

INFORMATION REQUIREMENTS

PROPOSED PROSPECT INFORMATION

Well Surface Location WD X (NAD 27) Y (NAD 27) Latitude Longitude 

MC 253 “A” OCS-G-24062 5042 1,204,584’ 10,431,637’ 28° 44’ 17.68” 88° 21’ 37.34” 

MC 253 “B” OCS-G-24062 4922 1,204,436’ 10,434,800’ 28° 44’ 48.98” 88° 21’ 39.41” 

MC 208 “C” OCS-G-32303 4750 1,202,630’ 10,439,071’ 28° 45’ 31.07” 88° 22’ 00.25” 

MC 208 “D” OCS-G-32303 4707 1,200,850’ 10,439,116’ 28° 45’ 31.31” 88° 22’ 20.26” 

MC 208 “E” OCS-G-32303 4645 1,203,299’ 10,446,834’ 28° 46’ 48.01” 88° 21’ 53.74” 

INFORMATION REQUIREMENTS

A) Blowout scenario 

The MC 253 well to be drilled to potential outlined in the Geological and Geophysical Information 

Section of this plan utilizing a typical subsea wellhead system, conductor, surface and intermediate 

casing strings from a pre-existing wellbore and a MODU rig with marine riser and a subsea BOP 

system. A hydrocarbon influx and a well control event occurring from the objective sand is modeled 

with no drill pipe or obstructions in the wellbore followed by a failure of the subsea BOP’s and loss of 

well control at the seabed. The simulated flow and worst case discharge (WCD) results for all wells 

are calculated and the highest WCD is used for this unrestricted blowout scenario. 

B) Estimated flow rate of the potential blowout 

Category Revised EP 

Type of Activity Drilling 

Facility Location (area / block) MC 253 

Facility Designation MODU 

Distance to Nearest Shoreline (miles) ~54 

Uncontrolled Blowout (Volume per day) 190,525 bbls 

Type of Fluid Crude 

C) Total volume and maximum duration of the potential blowout 

Duration of Flow (days) 114 days total (see Relief Well Response Estimate below) 

Total Volume of Spill (bbls) 21.7 MMBO based on 114 days of uncontrolled flow 

D) Assumptions and calculations used in determining the worst case discharge 

 

 Sbmitted under separate cover with the Proprietary Copy of this Plan. Omitted from Public 

 Information Copies. 

E) Potential for the well to bridge over 
BLOWOUT SCENARIO 

 MC 208-253 

Created by: S.L. Stegeman 

Last Revised: 7/13/2011 

Page 2 of 8 

Confidential

 2 

Mechanical failure/collapse of the borehole in a blowout scenario is influenced by several factors 

including in-situ stress, rock strength and fluid velocities at the sand face. Given the substantial fluid 

velocities inherent in the WCD, and the scenario as defined where the formation is not supported by a 

cased and cemented wellbore, it is possible that the borehole may fall/collapse/bridge over within a 

span of a few days, significantly reducing the outflow of the rates. For this blowout scenario, no 

bridging is considered. 

F) Likelihood for intervention to stop blowout 

The likelihood of surface intervention to stop a blowout is based on some of the following equipment 

specific to potential MODU’s to be contracted for this well. It is reasonable to assume that the sooner 

you are able to respond to the initial blowout, the better likelihood there is to control and contain the 

event due to reduced pressures at the wellhead, less exposure of well fluids to erode and 

compromise the well control equipment, and less exposure of hydrocarbons to the surface to 

safeguard personnel and equipment in an emergency situation. This equipment includes: 

• Secondary Acoustic BOP Control System – typically fitted on DP MODU’s presently operating 

in the GOM. This system has the ability to communicate and function specific BOP controls 

from the surface in the event of a failure of the primary umbilical control system. This system 

typically can establish BOP controls from the surface acoustic system package on the rig or 

by deploying a second acoustic package from a separate vessel of opportunity. This system 

may not be included on all MODU’s such as 4th generation moored rigs. This system is 

typically configured to function the following: 

- Blind/;shear ram close 

- Pipe ram close 

- LMRP disconnect 

• ROV Intervention BOP Control System – includes one or more ROV intervention panels 

mounted on the subsea BOP’s located on the seabed allows a ROV utilizing standard ROV 

stabs to access and function the specific BOP controls. These functions will be tested at the 

surface as part of the required BOP stump test and selectively at the seafloor to ensure 

proper functionality. These function include the following (at a minimum): 

- Blind/shear ram close 

- Pipe ram close 

- LMRP disconnect 

- WH disconnect 

 

• Deadman / Autoshear function – typically fitted on DP MODU’s and but to be on all MODU’s 

operating in the GOM according to new requirements, this equipment allows for an 

automated pre-programmed sequence of functions to close the casing shear rams and the 

blind/shear rams in the event of an inadvertent or emergency disconnect of the LMRP or loss 

of both hydraulic and electrical supply from the surface control system. 

In the event that the intervention systems for the subsea BOP’s fail, LLOG will initiate call out of a 

secondary containment / surface intervention system supported by the Helix Well Containment Group 

(HWCG) of which LLOG is a member. This system incorporates a capping stack capable of being 

deployed from the back of a vessel of opportunity equipped with an ROV or from the Helix Q4000 DP 

MODU. Based on the potential integrity concerns of the well, a “cap and flow” system can be 

deployed which may include the Helix Producer 1 capable of handling up to 55,000 BOPD flowback. 

The vertical intervention work is contingent upon the condition of the blowing out well and what 

equipment is intact to access the wellbore for kill or containment operations. The available 
BLOWOUT SCENARIO 

 MC 208-253 

Created by: S.L. Stegeman 

Last Revised: 7/13/2011 

Page 3 of 8 

Confidential

 3 

intervention equipment may also require modifications based on actual wellbore conditions. Standard 

equipment is available through the Helix Deepwater Containment System to fit the wellhead and BOP 

stack profiles used for the drilling of the above mentioned well. 

G) Availability of rig to drill relief well, rig constraints and timing of rigs 

LLOG currently has one deepwater MODU under contract (Noble Amos Runner moored semi). In the 

event of a blowout scenario that does not involve loss or damage to the rig such as an inadvertent 

disconnect of the BOP’s, then the existing contracted rig may be available for drilling the relief well 

and vertical intervention work. If the blowout scenario involves damage to the rig or loss of the BOP’s 

and riser, a replacement rig or rigs will be required. 

With the current activity level in the GOM, 25 to 35 deepwater MODU’S are potentially available to 

support the relief well drilling operations. Rig share and resource sharing agreements are in place 

between members of the Helix Well Containment Group. The ability to negotiate and contract an 

appropriate rig or rigs to drill relief wells is highly probable in a short period of time. If the rig or rigs 

are operating, the time to properly secure the well and mobe the rig to the relief well site location is 

estimated to be about 14 to 21 days. Dynamically positioned (DP) MODU’s would be the preferred 

option due to the logistical advantage versus a moored MODU which may add complications due to 

the mooring spread. 

VESSELS OF OPPORTUNITY

Based on the water depth restrictions for the proposed locations the following “Vessels of 

Opportunity” are presently available for utilization for intervention and containment and relief well 

operations. These may include service vessels and drilling rigs capable of working in the potential 

water depths and may include moored vessels and dynamically positioned vessels. The specific 

conditions of the intervention or relief well operations will dictate the “best fit” vessel to efficiently 

perform the desired results based on the blowout scenario. The list included below illustrates specific 

option that may vary according to the actual timing / availability at the time the vessels are needed. 

OPERATION SPECIFIC VESSEL OF OPPORTUNITY 

Intervention and Containment • Helix Q4000 (DP Semi) 

• Helix Producer 1 (DP FPU) 

Relief Well Drilling Rigs • Diamond Ocean Victory (Moored Semi) 

• Ensco 8502 (DP Semi) 

• Transocean Enterprise (DP Drillship) 

ROV / Multi-Purpose Service Vessels • Oceaneering (numerous DP ROV vessels) 

• HOS Achiever, Iron Horse 1 and 2 (DP MPSV) 

• Helix Pipe Lay Vessel (equipped w/ 6” PL – 75,000’) 

• Other ROV Vessels – (Chouest, HOS, Fugro, Subsea 7)

Shuttle Tanker / Barge Support • OSG Ship Management 

H) Measures taken to enhance ability to prevent blowout 

Pursuant to BOEM-2010-034 Final Interim Rules, measures to enhance the ability to prevent or 

reduce the likelihood of a blowout are largely based on proper planning and communication, 

identification of potential hazards, training and experience of personnel, use of good oil field practices 

and proper equipment that is properly maintained and inspected for executing drilling operations of 

the proposed well or wells to be drilled. 
BLOWOUT SCENARIO 

 MC 208-253 

Created by: S.L. Stegeman 

Last Revised: 7/13/2011 

Page 4 of 8 

Confidential

 4 

When planning and designing the well, ample time is spent analyzing offset data, performing any 

needed earth modeling and identifying any potential drilling hazards or well specific conditions to 

safeguard the safety of the crews when well construction operations are underway. Once the design 

criteria and well design is established, the well design is modeled for the lifecycle of the wellbore to 

ensure potential failure modes are eliminated. Pursuant to BOEM-2010-0034 Interim Final Rules 

implemented additional considerations of a minimum of 2 independent barriers for both internal and 

external flow paths in addition to proper positive and negative testing of the barriers. 

The proper training of crew members and awareness to identify and handle well control event is the 

best way prevent a blowout incident. Contractor’s personnel and service personnel training 

requirements are verified per regulatory requirements per guidelines issued in BOEM-2010-034 

Interim Final Rules. Drills are performed frequently to verify crew training and improve reaction times. 

Good communication between rig personnel, office support personnel is critical to the success of the 

operations. Pre-spud meetings are conducted with rig crews and service providers to discuss, inform 

and as needed improve operations and well plans for safety and efficiency considerations. Daily 

meetings are conducted to discuss planning and potential hazards to ensure state of preparedness 

and behavior is enforced to create an informed and safe culture for the operations. Any changes in 

the planning and initial wellbore design is incorporated and communicated in a Management of 

Change (MOC) process to ensure continuity for all personnel. 

Use of established good oil field practices that safeguard crews and equipment are integrated to 

incorporate LLOG’s, the contractor and service provider policies. 

Additional personnel and equipment will be used as needed to elevate awareness and provide real 

time monitoring of well conditions while drilling such as MWD/LWD/PWD tools used in the bottom 

hole assemblies. The tool configuration for each open hole section varies to optimize information 

gathered including the use of Formation-Pressure-While-Drilling (FPWD) tools to establish real time 

formation pressures and to be used to calibrates pore pressure models while drilling. Log information 

and pressure data is used by the drilling engineers, geologist and pore pressure engineers to 

maintain well control and reduced potential events such as well control events and loss circulation 

events. 

Mud loggers continuously monitor return drilling fluids, drill gas levels and cuttings as well as surface 

mud volumes and flow rates, rate of penetration and lithology/paleo to aid in understanding trends 

and geology being drilled. Remote monitoring of real time drilling parameters and evaluation of 

geologic markers and pore pressure indicators is used to identify potential well condition changes. 

Proper equipment maintenance and inspection program for same to before the equipment is required. 

Programmed equipment inspections and maintenance will be performed to ensure the equipment 

operability and condition. Operations will cease as needed in order to ensure equipment and well 

conditions are maintained and controlled for the safety of personnel, rig and subsurface equipment 

and the environment. 

I) Measures to conduct effective and early intervention in the event of a blowout 

In conjunction with the LLOG Exploration’s “Well Control Emergency Response Plan” and as required 

by NTL 2010-N06, the following is provided to demonstrate the potential time needed for performing 

secondary intervention and drilling of a relief well to handle potential worst case discharge for the 

proposed prospect. Specific plans are integrated into the Helix Well Containment Groups procures to 

be approved and submitted with the Application for Permit to Drill. Equipment availability, backup 

equipment and adaptability to the potential scenarios will need to be addressed based on the initial 
BLOWOUT SCENARIO 

 MC 208-253 

Created by: S.L. Stegeman 

Last Revised: 7/13/2011 

Page 5 of 8 

Confidential

 5 

site assessment of the seafloor conditions for intervention operations. Relief well equipment such as 

backup wellhead equipment and tubulars will be available in LLOG’s inventory for immediate 

deployment as needed to address frilling the relief well(s). 

SITE SPECIFIC PROPOSED RELIEF WELL AND INTERVENTION PLANNING

No platform was considered for drilling relief wells for this location due to location, water depth and 

lack of appropriate platform within the area. For this reason a moored or DP MODU will be preferred 

/ required. 

Nearest production pipeline tie-ins are located ~3 miles from ENI MC 296 subsea manifold located on 

MC 252 block. Other subsea manifold tie-in includes ~8 miles from ExxonMobil MC 211 and ~9 miles 

from ENI MC 299. Potential to utilize these lines in the event of a “cap and flow” scenario are 

possible. 

Relief well sites have been initially identified to address blowout scenarios for the potential geologic 

targets for the proposed wells. A total of 8 relief well surface locations are proposed for the 2 drill 

sites in the Proposed Exploration Plan wells. These 2 drill sites are the most probable well sites for a 

development scenario. The additional EP locations can be drilled from the 2 selected drillsites if 

needed. Based on actual seafloor state unforeseen at this time, the final location(s) may need to be 

revised. The locations have been selected based on proximity to the targets sands and potential 

shallow hazards. 

Proposed EP Well Proposed Relief Well X (NAD 27) Y (NAD 27) 

MC 208 “D” OCS-G-32303 MC 208 NW Relief Well 1,197,995’ 10,441,996’ 

 MC 208 NE Relief Well 1,203,377’ 10,440,148’ 

 MC 208 SSE Relief Well 1,201,434’ 10,435,866’ 

 MC 208SW Relief Well 1,198,871’ 10,436,666’ 

MC 253 “B” OCS-G-24062 MC 253 NW Relief Well 1,202,159’ 10,437,925’ 

 MC 253 NE Relief Well 1,206,312’ 10,437,206’ 

 MC 253 SE Relief Well 1,207,658’ 10,432,984’ 

 MC 253 SW Relief Well5 1,201,626’ 10,432,984’ 

RELIEF WELL RESPONSE TIME ESTIMATE

OPERATION TIME ESTIMATE

 (DAYS)

IMMEDIATE RESPONSE 

• safeguard personnel, render first-aid 

• make initial notifications 

• implement short term intervention (if possible) 

• implement spill control 

• develop Initial Action Plan 

 

 1 

INTERIM REPSONSE 

• establish Onsite Command Center and Emergency Management Team 

• assess well control issues 

• mobilize people and equipment (Helix DW Containment System) 

• implement short term intervention and containment (if possible) 

• develop Intervention Plan 

• initiate relief well planning 

• continue spill control measures 

 

 4 

INTERVENTION AND CONTAIMENT OPERATIONS 
BLOWOUT SCENARIO 

 MC 208-253 

Created by: S.L. Stegeman 

Last Revised: 7/13/2011 

Page 6 of 8 

Confidential

 6 

• mobilize equipment and initiate intervention and containment operations

• perform TA operations and mobilize relief wells rig(s) 

• finalize relief well plans, mobilize spud equipment, receive approvals 

• continue spill control measures 

 14 

RELIEF WELL(S) OPERATIONS 

• continue intervention and containment measures

• continue spill control measures

• drill relief well (s) 

 75 

PERFORM HYDRAULIC KILL OPERATIONS / SECURE BLOWNOUT WELL 

• continue intervention and containment measures

• continue spill control measures

• perform hydraulic kill operations, monitor well, secure well

 

 20 

 ESTIMATED TOTAL DAYS OF UNCONTROLLED FLOW 114 

SECURE RELIELF WELL(S) / PERFORM P&A / TA OPERATIONS / DEMOBE 30 

 TOTAL DAYS 144 
BLOWOUT SCENARIO 

 MC 208-253 

Created by: S.L. Stegeman 

Last Revised: 7/13/2011 

Page 7 of 8 

Confidential

 7 
BLOWOUT SCENARIO 

 MC 208-253 

Created by: S.L. Stegeman 

Last Revised: 7/13/2011 

Page 8 of 8 

Confidential

 8 
Mississippi Canyon Block 253 (OCS-G 24062) 6/21/2011 

Mississippi Canyon Block 208 (OCS-G-32303) 

Revised Exploration Plan 5

 

APPENDIX C 

GEOLOGICAL AND GEOPHYSICAL INFORMATION

(30 CFR Part 250.214 and 250.244) 

A. Geological Description

Included as Attachment D are the geological targets and a narrative of 

trapping features proposed in this Plan. No change – Refer to Attachment D 

of the Initial EP for MC 253, OCS-G-24062 Lease and MC 208, OCS-G32303, Control No. N-09406 approved on October 22, 2009. 

B. Structure Contour Maps

Included as Attachment E are current structure maps (depth base and 

expressed in feet subsea) depicting the entire lease coverage area; drawn on 

top of the prospective hydrocarbon sands. The maps depict each proposed 

bottom hole location and applicable geological cross section. No change – 

Refer to Attachment E of the Initial EP for MC 253, OCS-G-24062 Lease 

and MC 208, OCS-G-32303, Control No. N-09406 approved on October 

22, 2009. 

 

C. Interpreted Seismic Lines

Included as Attachment F is a copy of the migrated and annotated (shot 

points, time lines, well paths) deep seismic line within 500 feet of the surface 

location being proposed in this Plan. No change – Refer to Attachment F of 

the Initial EP for MC 253, OCS-G-24062 Lease and MC 208, OCS-G32303, Control No. N-09406 approved on October 22, 2009. 

D. Geological Structure Cross-Sections

An interpreted geological cross section depicting the proposed well locations 

and depth of the proposed wells is included as Attachment G. Such cross 

section corresponds to each seismic line being submitted. No change – Refer 

to Attachment G of the Initial EP for MC 253, OCS-G-24062 Lease and 

MC 208, OCS-G-32303, Control No. N-09406 approved on October 22, 

2009. 
Mississippi Canyon Block 253 (OCS-G 24062) 6/16/2011 

Mississippi Canyon Block 208 (OCS-G-32303) 

Revised Exploration Plan 6

 

E. Shallow Hazards Report

C & C Technologies conducted a high resolution geophysical survey in 

Mississippi Canyon Blocks 208 and 253 during May 2009 on behalf of LLOG 

Exploration Offshore, Inc. The purpose of the survey was to evaluate 

geologic conditions and inspect for potential hazards or constraints to lease 

development. Four (4) copies of the report was submitted to Minerals 

Management Service (BOEMRE) under separate cover. No change – Refer 

to Initial EP for MC 253, OCS-G-24062 Lease and MC 208, OCS-G32303, Control No. N-09406 approved on October 22, 2009. 

F. Shallow Hazards Assessment

Utilizing the 3D deep seismic exploration data a shallow hazards analysis was 

prepared for the proposed surface locations, evaluating seafloor and 

subsurface geologic and manmade features and conditions, and is included as 

Attachment H. No change – Refer to Attachment H of the Initial EP for 

MC 253, OCS-G-24062 Lease and MC 208, OCS-G-32303, Control No. N09406 approved on October 22, 2009. 

G. High Resolution Seismic Lines

LLOG provided exploration 3-D seismic data for the evaluation of the 

proposed surface disturbance operations. No change – Refer to the Initial 

EP for MC 253, OCS-G-24062 Lease and MC 208, OCS-G-32303, 

Control No. N-09406 approved on October 22, 2009. 

H. Stratigraphic Column

A generalized biostratigraphic/lithostratigraphic column from the seafloor to 

the total depth of the proposed wells is included as Attachment I. No change 

– Refer to Attachment I of the Initial EP for MC 253, OCS-G-24062 

Lease and MC 208, OCS-G-32303, Control No. N-09406 approved on 

October 22, 2009. 

I. Time vs Depth Tables

LLOG has determined that there is existing sufficient well control data for the 

target areas proposed in this plan; therefore, tables providing seismic time 

versus depth for the proposed well locations are not required. No change – 

Refer to Initial EP for MC 253, OCS-G-24062 Lease and MC 208, OCSG-32303, Control No. N-09406 approved on October 22, 2009. 





LLOG Exploration Company Gardline Report 8025

Well Clearance Letters – Mississippi Canyon Blocks 208 & 253 – Proposed MC253-A and B Well Locations Volume 3

61

Public Shallow Hazards Statement – MC253-A

July 1, 2011

US Department of the Interior

Minerals Management Service

1201 Elmwood Park Blvd.

New Orleans, LA 70213-2394

Attention: 

Reference: Shallow Hazards Analysis

Mississippi Canyon Block 253

OCS-(G 24062)

Ladies/Gentlemen:

LLOG Exploration Company contracted Gardline Surveys, Inc. to prepare a Well Clearance Letter for

the proposed MC253-A well location in Block 253, Mississippi Canyon Area (OCS-G 24062). This letter 

addresses seafloor and shallow geologic conditions that may impact exploratory drilling operations 

within 2,000ft of the proposed wellsite. The depth limit of this geohazard assessment is to Horizon H40 

+750ms at -9,769ft below sea surface (4,727ft below seabed).

This hazards summary letter is issued as a supplement to Gardline Reports No. 8025 entitled 3D 

Geohazard Assessment, Gulf of Mexico, Mississippi Canyon, Blocks MC208 and 253, Volume 1, May 

2009 and Volume 2, MC253-A and B Well Clearance Letters, July 2011.

Seabed Hazards. The seabed presents a sloping seabed exhibiting a number of regions of diapirically 

induced uplift and seabed faulting. None of these features directly affect the proposed MC253-A well 

location.

There are no indications of seabed fluid seeps within 2,000ft of the well location.

No existing seabed infrastructure is located in the area.

Sub-Seabed Hazards. A Slight Risk of Shallow Water Flow is interpreted where a number of 

indicators of higher energy sandy interbeds are observed within the mid-part of Unit D and throughout 

Unit E.

A Slight Risk of Gas anomaly is observed at Horizon H30.

A Moderate Risk of Gas anomaly is observed within Unit E. Full well control is expected to have been 

established by this level.
LLOG Exploration Company Gardline Report 8025

Well Clearance Letters – Mississippi Canyon Blocks 208 & 253 – Proposed MC253-A and B Well Locations Volume 3

62

Proposed MC253-A Location (Surface)

Location Coordinates

NAD 27 Datum - Clarke 1866 Ellipsoid UTM Zone 16N

Latitude 28° 44' 17.68” North Easting 1,204,584 US ft E

Longitude 88° 21’ 37.34” West Northing 10,431,637 US ft N

FWL of Mississippi Canyon 253 744 US ft Inline 17301

FNL of Mississippi Canyon 253 6,923 US ft Crossline 14119

Water Depth: -5,042 ft Slope: 3.0° SE

Nearest Shoreline 53.99 Miles @ 298° 8’ 08.86’’

Port of Operation Fourchon 116.06 Miles @ 284° 5’ 34.73’’

Nearest Manned Platform MC127 A-Horn Mountain 20.43 Miles @ 65° 04’ 57.56’’

Conclusions and Recommendations. A Slight Risk of Gas is interpreted at Horizon H30, Drilling 

Caution is advised. A Slight Risk of Shallow Water Flow is interpreted within the mid part of Unit D and 

throughout Unit E. Appropriate drilling methodology to contain a minor, non-persistent shallow water 

flow event should be utilized when drilling this well.

Sincerely,

LLOG Exploration Company

Jaime Mata

Geological Technician

PUBLIC INFORMATION
LLOG Exploration Company Gardline Report 8025

Well Clearance Letters – Mississippi Canyon Blocks 208 & 253 – Proposed MC253-A and B Well Locations Volume 3

63

Public Shallow Hazards Statement – MC253-B

July 1, 2011

US Department of the Interior

Minerals Management Service

1201 Elmwood Park Blvd.

New Orleans, LA 70213-2394

Attention: 

Reference: Shallow Hazards Analysis

Mississippi Canyon Block 253

OCS-(G 24062)

Ladies/Gentlemen:

LLOG Exploration Company contracted Gardline Surveys, Inc. to prepare a Well Clearance Letter for 

the proposed MC253-B well location in Block 253, Mississippi Canyon Area (OCS-G 24062). This letter 

addresses seafloor and shallow geologic conditions that may impact exploratory drilling operations 

within 2,000ft of the proposed wellsite. The depth limit of this geohazard assessment is to Horizon H40 

+ 750ms at -9,783ft below sea surface (4,861ft below seabed).

This hazards summary letter is issued as a supplement to Gardline Reports No. 8025 entitled 3D 

Geohazard Assessment, Gulf of Mexico, Mississippi Canyon, Blocks MC208 and 253, Volume 1, May 

2009 and Volume 3, MC253-A and B Well Clearance Letters, July 2011.

Seabed Hazards. The seabed presents a sloping seabed exhibiting a number of regions of diapirically 

induced uplift and seabed faulting. None of these features directly affect the proposed MC253-B well 

location.

There are no indications of seabed fluid seeps within 2,000ft of the well location.

No existing seabed infrastructure is located in the area.

Sub-Seabed Hazards. A Slight Risk of Shallow Water Flow is interpreted where a number of 

indicators of higher energy sandy interbeds are observed within the mid-part of Unit D and throughout 

Unit E.

A Moderate Risk of Gas anomaly is observed within Unit E. Full well control is expected to have been 

established by this level.
LLOG Exploration Company Gardline Report 8025

Well Clearance Letters – Mississippi Canyon Blocks 208 & 253 – Proposed MC253-A and B Well Locations Volume 3

64

Proposed MC253-B Location (Surface)

Location Coordinates

NAD 27 Datum - Clarke 1866 Ellipsoid UTM Zone 16N

Latitude 28° 44' 48.98” North Easting 1,204,436 US ft E

Longitude 88° 21’ 39.41” West Northing 10,434,800 US ft N

FWL of Mississippi Canyon 253 596 US ft Inline 17334

FNL of Mississippi Canyon 253 3,760 US ft Crossline 14176

Water Depth: -4,922 ft Slope: 3.4° SE

Nearest Shoreline 53.99 Miles @ 298° 8’ 08.86’’

Port of Operation Fourchon 116.06 Miles @ 284° 5’ 34.73’’

Nearest Manned Platform MC127 A-Horn Mountain 20.21 Miles @ 66° 39’ 22.34’’

Conclusions and Recommendations. A Slight Risk of Shallow Water Flow is interpreted within the 

mid part of Unit D and throughout Unit E. Appropriate drilling methodology to contain a minor, nonpersistent shallow water flow event should be utilized when drilling this well.

Sincerely,

LLOG Exploration Company

Jaime Mata

Geological Technician

PUBLIC INFORMATION
LLOG Exploration Company Gardline Report 8025

Well Clearance Letters – Mississippi Canyon Blocks 208 & 253 – Proposed MC208-C, D and E Well Locations Volume 2

90

Public Shallow Hazards Statement – MC208-C

July 1, 2011

US Department of the Interior

Minerals Management Service

1201 Elmwood Park Blvd.

New Orleans, LA 70213-2394

Attention: 

Reference: Shallow Hazards Analysis

Mississippi Canyon Block 208

OCS-(G 32303)

Ladies/Gentlemen:

LLOG Exploration Company contracted Gardline Surveys, Inc. to prepare a Well Clearance Letter for 

the proposed MC208-C well location in Block 208, Mississippi Canyon Area (OCS-G 32303). This letter 

addresses seafloor and shallow geologic conditions that may impact exploratory drilling operations 

within 2,000ft of the proposed wellsite. The depth limit of this geohazard assessment is to Horizon H40 

+750ms at -9,840ft below sea surface (5,090ft below seabed).

This hazards summary letter is issued as a supplement to Gardline Reports No. 8025 entitled 3D 

Geohazard Assessment, Gulf of Mexico, Mississippi Canyon, Blocks MC208 and 253, Volume 1, May 

2009 and Volume 2, MC208-C, D and E Well Clearance Letters, July 2011.

Seabed Hazards. The seabed presents a sloping seabed exhibiting a number of regions of diapirically 

induced uplift and seabed faulting. None of these features directly affect the proposed MC208-C well 

location.

There are no indications of seabed fluid seeps within 2,000ft of the well location.

No existing seabed infrastructure is located in the area.

Sub-Seabed Hazards. A Slight Risk of Shallow Water Flow is interpreted where a number of 

indicators of higher energy sandy interbeds are observed within the mid-part of Unit D and throughout 

Unit E.

A Moderate Risk of Gas anomaly is observed within Unit E. Full well control is expected to have been 

established by this level.
LLOG Exploration Company Gardline Report 8025

Well Clearance Letters – Mississippi Canyon Blocks 208 & 253 – Proposed MC208-C, D and E Well Locations Volume 2

91

Proposed MC208-C Location (Surface)

Location Coordinates

NAD 27 Datum - Clarke 1866 Ellipsoid UTM Zone 16N

Latitude 28° 45' 31.07” North Easting 1,202,630 US ft E

Longitude 88° 22’ 0.25” West Northing 10,439,071 US ft N

FEL of Mississippi Canyon 208 1,210 US ft Inline 17360

FSL of Mississippi Canyon 208 511 US ft Crossline 14281

Water Depth: -4,750 ft Slope: 2.2° SE

Nearest Shoreline 49.95 Miles @ 296° 43’ 25.6’’

Port of Operation Fourchon 112.44 Miles @ 282° 58’ 56.9’’

Nearest Manned Platform MC127 A-Horn Mountain 20.23 Miles @ 69° 8’ 40.69’’

Conclusions and Recommendations. A Slight Risk of Shallow Water Flow is interpreted within the 

mid part of Unit D and throughout Unit E. Appropriate drilling methodology to contain a minor, nonpersistent shallow water flow event should be utilized when drilling this well.

Sincerely,

LLOG Exploration Company

Jaime Mata

Geological Technician

PUBLIC INFORMATION
LLOG Exploration Company Gardline Report 8025

Well Clearance Letters – Mississippi Canyon Blocks 208 & 253 – Proposed MC208-C, D and E Well Locations Volume 2

92

Public Shallow Hazards Statement – MC208-D

July 1, 2011

US Department of the Interior

Minerals Management Service

1201 Elmwood Park Blvd.

New Orleans, LA 70213-2394

Attention: 

Reference: Shallow Hazards Analysis

Mississippi Canyon Block 208

OCS-(G 32303)

Ladies/Gentlemen:

LLOG Exploration Company contracted Gardline Surveys, Inc. to prepare a Well Clearance Letter for 

the proposed MC208-D well location in Block 208, Mississippi Canyon Area (OCS-G 32303). This letter 

addresses seafloor and shallow geologic conditions that may impact exploratory drilling operations 

within 2,000ft of the proposed wellsite. The depth limit of this geohazard assessment is to Horizon H40 

+750ms at -9,752ft below sea surface (5,045ft below seabed).

This hazards summary letter is issued as a supplement to Gardline Reports No. 8025 entitled 3D 

Geohazard Assessment, Gulf of Mexico, Mississippi Canyon, Blocks MC208 and 253, Volume 1, May 

2009 and Volume 2, MC208-C, D and E Well Clearance Letters, July 2011.

Seabed Hazards. The seabed presents a sloping seabed exhibiting a number of regions of diapirically 

induced uplift and seabed faulting. None of these features directly affect the proposed MC208-D well 

location.

There are no indications of seabed fluid seeps within 2,000ft of the well location.

No existing seabed infrastructure is located in the area.

Sub-Seabed Hazards. A Slight Risk of Shallow Water Flow is interpreted where a number of 

indicators of higher energy sandy interbeds are observed within the mid-part of Unit D and throughout 

Unit E.

A Slight Risk of Gas anomaly is observed within Unit E. Full well control is expected to have been 

established by this level.
LLOG Exploration Company Gardline Report 8025

Well Clearance Letters – Mississippi Canyon Blocks 208 & 253 – Proposed MC208-C, D and E Well Locations Volume 2

93

Proposed MC208-D Location (Surface)

Location Coordinates

NAD 27 Datum - Clarke 1866 Ellipsoid UTM Zone 16N

Latitude 28° 45' 31.31” North Easting 1,200,850 US ft E

Longitude 88° 22’ 20.26” West Northing 10,439,116 US ft N

FEL of Mississippi Canyon 208 2,990 US ft Inline 17342

FSL of Mississippi Canyon 208 556 US ft Crossline 14312

Water Depth: -4,707 ft Slope: 1.8° SE

Nearest Shoreline 49.95 Miles @ 296° 43’ 25.6’’

Port of Operation Fourchon 112.44 Miles @ 282° 58’ 56.9’’

Nearest Manned Platform MC127 A-Horn Mountain 20.54 Miles @ 69° 30’ 5.93’’

Conclusions and Recommendations. A Slight Risk of Shallow Water Flow is interpreted within the 

mid part of Unit D and throughout Unit E. Appropriate drilling methodology to contain a minor, nonpersistent shallow water flow event should be utilized when drilling this well.

Sincerely,

LLOG Exploration Company

Jaime Mata

Geological Technician

PUBLIC INFORMATION
LLOG Exploration Company Gardline Report 8025

Well Clearance Letters – Mississippi Canyon Blocks 208 & 253 – Proposed MC208-C, D and E Well Locations Volume 2

94

Public Shallow Hazards Statement – MC208-E

July 1, 2011

US Department of the Interior

Minerals Management Service

1201 Elmwood Park Blvd.

New Orleans, LA 70213-2394

Attention: 

Reference: Shallow Hazards Analysis

Mississippi Canyon Block 208

OCS-(G 32303)

Ladies/Gentlemen:

LLOG Exploration Company contracted Gardline Surveys, Inc. to prepare a Well Clearance Letter for 

the proposed MC208-E well location in Block 208, Mississippi Canyon Area (OCS-G 32303). This letter 

addresses seafloor and shallow geologic conditions that may impact exploratory drilling operations 

within 2,000ft of the proposed wellsite. The depth limit of this geohazard assessment is to Horizon H40 

+750ms at -9,637ft below sea surface (4,992ft below seabed).

This hazards summary letter is issued as a supplement to Gardline Reports No. 8025 entitled 3D 

Geohazard Assessment, Gulf of Mexico, Mississippi Canyon, Blocks MC208 and 253, Volume 1, May 

2009 and Volume 2, MC208-C, D and E Well Clearance Letters, July 2011.

Seabed Hazards. The seabed presents a sloping seabed exhibiting a number of regions of diapirically 

induced uplift and seabed faulting. None of these features directly affect the proposed MC208-E well 

location.

There are no indications of seabed fluid seeps within 2,000ft of the well location.

No existing seabed infrastructure is located in the area.

Sub-Seabed Hazards. A Slight Risk of Shallow Water Flow is interpreted where a number of 

indicators of higher energy sandy interbeds are observed within the mid-part of Unit D and throughout 

Unit E.

A Moderate Risk of Gas anomaly is observed within Unit E. Full well control is expected to have been 

established by this level.
LLOG Exploration Company Gardline Report 8025

Well Clearance Letters – Mississippi Canyon Blocks 208 & 253 – Proposed MC208-C, D and E Well Locations Volume 2

95

Proposed MC208-E Location (Surface)

Location Coordinates

NAD 27 Datum - Clarke 1866 Ellipsoid UTM Zone 16N

Latitude 28° 46' 48.01” North Easting 1,203,299 US ft E

Longitude 88° 21’ 53.74” West Northing 10,446,834 US ft N

FEL of Mississippi Canyon 208 541 US ft Inline 17451

FNL of Mississippi Canyon 208 7,566 US ft Crossline 14403

Water Depth: -4,645 ft Slope: 3.8° SE

Nearest Shoreline 49.95 Miles @ 296° 43’ 25.6’’

Port of Operation Fourchon 112.44 Miles @ 282° 58’ 56.9’’

Nearest Manned Platform MC127 A-Horn Mountain 19.63 Miles @ 73° 1’ 33.83’’

Conclusions and Recommendations. A Slight Risk of Shallow Water Flow is interpreted within the 

mid part of Unit D and throughout Unit E. Appropriate drilling methodology to contain a minor, nonpersistent shallow water flow event should be utilized when drilling this well.

Sincerely,

LLOG Exploration Company

Jaime Mata

Geological Technician

PUBLIC INFORMATION
LLOG Exploration Company Gardline Report 8025

Well Clearance Letters – Mississippi Canyon Blocks 208 & 253 – Proposed MC253-A and B Well Locations Volume 3

54

ANCHORING ASSESSMENT – Proposed MC253-A Well Location

Proposed MC253-A Location (Surface)

Location Coordinates

NAD 27 Datum - Clarke 1866 Ellipsoid UTM Zone 16N

Latitude 28° 44' 17.68” North Easting 1,204,584 US ft E

Longitude 88° 21’ 37.34” West Northing 10,431,637 US ft N

FWL of Mississippi Canyon 253 744 US ft Inline 17301

FNL of Mississippi Canyon 253 6,923 US ft Crossline 14119

Water Depth: -5,042 ft Slope: 3.0° SE

Nearest Shoreline 53.99 Miles @ 298° 8’ 08.86’’

Port of Operation Fourchon 116.06 Miles @ 284° 5’ 34.73’’

Nearest Manned Platform MC127 A-Horn Mountain 20.43 Miles @ 65° 04’ 57.56’’

Anchor Pattern:

LLOG Exploration Company has not as yet issued a specific anchor spread to retain the 

drilling rig. The anchor radius illustrated on Plats and Charts for the proposed Block MC253-A 

wellsite is the maximum predicted radius of 12,000ft plus a 1,000ft Buffer Zone. An anchorspread pattern can be designed as an addendum to this report, if required, after the drilling rig 

has been identified. The anchor pattern will be designed to avoid any infrastructure and 

potentially sensitive seabed habitats. 

Bathymetry

Water depth at the proposed MC253-A well location is -5,042ft below sea-surface. The 

seafloor deepens to the southeast at 3.0°.

Seabed Morphology, Faults and Sensitive Sessile Benthic Communities

The seabed within the radius of the proposed anchor pattern deepens to the southeast. 

The proposed well location is located on the northwest flank of an elongate salt withdrawal 

mini-basin. Anchors placed to the southeast could contact the uplifted region of seabed due 

to underlying salt diapirism. Slightly firmer sediments may occur in this region which may 

reduce anchor penetration.

Localized areas considered favourable for sensitive sessile benthic community development 

occur in the extreme southeast of the 12,000ft anchor radius. These regions will be avoided 

by at least 250ft by all anchoring operations.

A seabed fault is observed 3,800ft to the north, but will not adversely affect anchoring 

operations.
LLOG Exploration Company Gardline Report 8025

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55

No other features, which may impact anchor emplacement, are observed within the 12,000ft 

anchor radius.

All anchors will be positioned using a precise DGPS system.

Charts 1, 2, and 3 illustrate an anchor radius of 12,000ft for the proposed MC253-A Location 

at 1”=1,000ft. Proposed MC253-A Location Anchor Plat (overleaf) illustrates the anchor radius 

at 1”=4,000ft.
0 4,000 8,000 16,000 Feet

0 1,000 2,000 4,000 Meters

Chart scale 1" = 4,000'

Anchor Plat (MC253-A)

Proposed MC253-A Well Location

(1,204,584ft E / 10,431,637ft N)

Proposed MC253-B Well Location

(1,204,436ft E / 10,434,800ft N)

Proposed MC208-C Well Location

(1,202,630ft E / 10,439,071ft N)

3® 3

3

3

3® 3

3

3

3® 3

3

3

Depth in feet below sea surface to seabed,

contoured at 100ft intervals

±

-5200

3® 3

3

3

3® 3

3

3

3® 3

3

3

3® 3

3

3

6

12,000ft Radius

2,000ft Radius

1,000ft Buffer Zone

Proposed MC253-A

MC252-1

Proposed MC253-B

Proposed MC208-C

Proposed MC208-D

-4900

-5000

-5100

-4800

-4700

-5200

-4600 -4500 -4400

-5300

-4300

-4800

-4900

-4800

-4900

-4300

88°20'0"W88°22'0"W88°24'0"W

28°46'0"N

28°44'0"N

1,190,0001,200,0001,210,000

10,420,000

10,430,000

10,440,000

Proposed MC208-D Well Location

(1,200,850ft E / 10,439,116ft N) 3® 3

3

3

Seabed fault intersection tick denotes

downthrown side

Fluid expulsion sites favorable for possible

sensitive sessile benthic community development

Upper and lower limits of escarpment
LLOG Exploration Company Gardline Report 8025

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57

ANCHORING ASSESSMENT – Proposed MC253-B Well Location

Proposed MC253-B Location (Surface)

Location Coordinates

NAD 27 Datum - Clarke 1866 Ellipsoid UTM Zone 16N

Latitude 28° 44' 48.98” North Easting 1,204,436 US ft E

Longitude 88° 21’ 39.41” West Northing 10,434,800 US ft N

FWL of Mississippi Canyon 253 596 US ft Inline 17334

FNL of Mississippi Canyon 253 3,760 US ft Crossline 14176

Water Depth: -4,922 ft Slope: 3.4° SE

Nearest Shoreline 53.99 Miles @ 298° 8’ 08.86’’

Port of Operation Fourchon 116.06 Miles @ 284° 5’ 34.73’’

Nearest Manned Platform MC127 A-Horn Mountain 20.21 Miles @ 66° 39’ 22.34’’

Anchor Pattern:

LLOG Exploration Company has not as yet issued a specific anchor spread to retain the 

drilling rig. The anchor radius illustrated on Plats and Charts for the proposed Block MC253-B 

wellsite is the maximum predicted radius of 12,000ft plus a 1,000ft Buffer Zone. An anchorspread pattern can be designed as an addendum to this report, if required, after the drilling rig 

has been identified. The anchor pattern will be designed to avoid any infrastructure and 

potentially sensitive seabed habitats. 

Bathymetry

Water depth at the proposed MC253-B well location is -4,922ft below sea-surface. The 

seafloor deepens to the southeast at 3.4°.

Seabed Morphology, Faults and Sensitive Sessile Benthic Communities

The seabed within the radius of the proposed anchor pattern deepens to the southeast. 

The proposed well location is located on the northwest flank of an elongate salt withdrawal 

mini-basin. Anchors placed to the southeast and ENE could contact the uplifted region of 

seabed due to underlying salt diapirism. Slightly firmer sediments may occur in this region 

which may reduce anchor penetration.

No areas within the anchor radius area have the potential for sensitive sessile benthic

communities.

A seabed fault is observed 700ft to the north, but is not interpreted to be a problem to 

anchoring.

No other features, which may impact anchor emplacement, are observed within the 12,000ft 
LLOG Exploration Company Gardline Report 8025

Well Clearance Letters – Mississippi Canyon Blocks 208 & 253 – Proposed MC253-A and B Well Locations Volume 3

58

anchor radius.

All anchors will be positioned using a precise DGPS system.

Charts 1, 2, and 3 illustrate an anchor radius of 12,000ft for the proposed MC253-B Location 

at 1”=1,000ft. Proposed MC253-B Location Anchor Plat (overleaf) illustrates the anchor radius 

at 1”=4,000ft.
0 4,000 8,000 16,000 Feet

0 1,000 2,000 4,000 Meters

Chart scale 1" = 4,000'

Anchor Plat (MC253-B)

Proposed MC253-A Well Location

(1,204,584ft E / 10,431,637ft N)

Proposed MC253-B Well Location

(1,204,436ft E / 10,434,800ft N)

Proposed MC208-C Well Location

(1,202,630ft E / 10,439,071ft N)

3® 3

3

3

3® 3

3

3

3® 3

3

3

Depth in feet below sea surface to seabed,

contoured at 100ft intervals

±

-5200

3® 3

3

3

3® 3

3

3

3® 3

3

3

3® 3

3

3

3® 3

3

3

6

12,000ft Radius

2,000ft Radius

1,000ft Buffer Zone

Proposed MC253-A

MC252-1

Proposed MC253-B

Proposed MC208-D Proposed MC208-C

Proposed MC208-E

-4900

-5000

-4800

-5100

-4700

-5200 -4600

-4500 -4400

-4300

-4200

-4100

-4800

-4900

-4800 -4900

-4300

88°20'0"W88°22'0"W88°24'0"W

28°46'0"N

28°44'0"N

1,190,0001,200,0001,210,000

10,430,000

10,440,000

Proposed MC208-D Well Location

(1,200,850ft E / 10,439,116ft N) 3® 3

3

3

Seabed fault intersection tick denotes

downthrown side

Fluid expulsion sites favorable for possible

sensitive sessile benthic community development

Upper and lower limits of escarpment
LLOG Exploration Company Gardline Report 8025

Well Clearance Letters – Mississippi Canyon Blocks 208 & 253 – Proposed MC208-C, D and E Well Locations Volume 2

80

ANCHORING ASSESSMENT – Proposed MC208-C Well Location

Proposed MC208-C Location (Surface)

Location Coordinates

NAD 27 Datum - Clarke 1866 Ellipsoid UTM Zone 16N

Latitude 28° 45' 31.07” North Easting 1,202,630 US ft E

Longitude 88° 22’ 0.25” West Northing 10,439,071 US ft N

FEL of Mississippi Canyon 208 1,210 US ft Inline 17360

FSL of Mississippi Canyon 208 511 US ft Crossline 14281

Water Depth: -4,750 ft Slope: 2.2° SE

Nearest Shoreline 49.95 Miles @ 296° 43’ 25.6’’

Port of Operation Fourchon 112.44 Miles @ 282° 58’ 56.9’’

Nearest Manned Platform MC127 A-Horn Mountain 20.23 Miles @ 69° 8’ 40.69’’

Anchor Pattern:

LLOG Exploration Company has not as yet issued a specific anchor spread to retain the 

drilling rig. The anchor radius illustrated on Plats and Charts for the proposed Block MC208-C

wellsite is the maximum predicted radius of 12,000ft plus a 1,000ft Buffer Zone. An anchorspread pattern can be designed as an addendum to this report, if required, after the drilling rig 

has been identified. The anchor pattern will be designed to avoid any infrastructure and 

potentially sensitive seabed habitats. 

Bathymetry

Water depth at the proposed MC208-C well location is -4,750ft below sea-surface. The 

seafloor deepens to the southeast at 2.2°.

Seabed Morphology, Faults and Sensitive Sessile Benthic Communities

The seabed within the radius of the proposed anchor pattern deepens to the southeast. 

The proposed well location is located upslope from an elongated mini-basin caused by subsalt uplift to the north, south and east. Seabed is relatively even and predominantly 

featureless, except for in the extreme ENE of the anchor radius where the lower flank of the 

salt uplift occurs. The lower escarpment region may exhibit slightly firmer sediment types 

which may reduce anchor penetration.

No areas within the anchor radius area have the potential for sensitive sessile benthic

communities.

Seabed faults are observed to the southeast, but are not interpreted to affect anchoring. 

No other features, which may impact anchor emplacement, are observed within the 12,000ft 
LLOG Exploration Company Gardline Report 8025

Well Clearance Letters – Mississippi Canyon Blocks 208 & 253 – Proposed MC208-C, D and E Well Locations Volume 2

81

anchor radius.

All anchors will be positioned using a precise DGPS system.

Charts 1, 2, and 3 illustrate an anchor radius of 12,000ft for the proposed MC208-C Location 

at 1”=1,000ft. Proposed MC208-C Location Anchor Plat (overleaf) illustrates the anchor radius

at 1”=4,000ft.
0 4,000 8,000 16,000 Feet

0 1,000 2,000 4,000 Meters

Chart scale 1" = 4,000'

Anchor Plat (MC208-C)

Proposed MC253-A Well Location

(1,204,584ft E / 10,431,637ft N)

Proposed MC253-B Well Location

(1,204,436ft E / 10,434,800ft N)

Proposed MC208-C Well Location

(1,202,630ft E / 10,439,071ft N)

3® 3

3

3

3® 3

3

3

3® 3

3

3

Depth in feet below sea surface to seabed,

contoured at 100ft intervals

±

-4800

3® 3

3

3

3® 3

3

3

3® 3

3

3

3® 3

3

3

3® 3

3

3

6

12,000ft Radius

2,000ft Radius

1,000ft Buffer Zone

Proposed MC253-A

MC252-1

Proposed MC253-B

Proposed MC208-DProposed MC208-C

Proposed MC208-E

-5000

-4900

-4800

-4700

-5100

-4600

-4500

-4400

-5200

-4300

-4200

-4100

-4800

-4900

-4300

88°24'0"W88°22'0"W88°20'0"W

28°46'0"N

28°44'0"N

1,190,0001,200,0001,210,000

10,430,000

10,440,000

10,450,000

Proposed MC208-D Well Location

(1,200,850ft E / 10,439,116ft N)

Proposed MC208-E Well Location

(1,203,299ft E, 10,446,834ft N)

3® 3

3

3

3® 3

3

3

Seabed fault intersection tick denotes

downthrown side

Upper and lower limits of escarpment
LLOG Exploration Company Gardline Report 8025

Well Clearance Letters – Mississippi Canyon Blocks 208 & 253 – Proposed MC208-C, D and E Well Locations Volume 2

83

ANCHORING ASSESSMENT – Proposed MC208-D Well Location

Proposed MC208-D Location (Surface)

Location Coordinates

NAD 27 Datum - Clarke 1866 Ellipsoid UTM Zone 16N

Latitude 28° 45' 31.31” North Easting 1,200,850 US ft E

Longitude 88° 22’ 20.26” West Northing 10,439,116 US ft N

FEL of Mississippi Canyon 208 2,990 US ft Inline 17342

FSL of Mississippi Canyon 208 556 US ft Crossline 14312

Water Depth: -4,707 ft Slope: 1.8° SE

Nearest Shoreline 49.95 Miles @ 296° 43’ 25.6’’

Port of Operation Fourchon 112.44 Miles @ 282° 58’ 56.9’’

Nearest Manned Platform MC127 A-Horn Mountain 20.54 Miles @ 69° 30’ 5.93’’

Anchor Pattern:

LLOG Exploration Company has not as yet issued a specific anchor spread to retain the 

drilling rig. The anchor radius illustrated on Plats and Charts for the proposed Block MC208-D

wellsite is the maximum predicted radius of 12,000ft plus a 1,000ft Buffer Zone. An anchorspread pattern can be designed as an addendum to this report, if required, after the drilling rig 

has been identified. The anchor pattern will be designed to avoid any infrastructure and 

potentially sensitive seabed habitats. 

Bathymetry

Water depth at the proposed MC208-D well location is -4,707ft below sea-surface. The 

seafloor deepens to the southeast at 1.8°.

Seabed Morphology, Faults and Sensitive Sessile Benthic Communities

The seabed within the radius of the proposed anchor pattern deepens to the southeast. 

The proposed well location is located upslope from an elongated mini-basin caused by subsalt uplifting to the north, south and east. No major changes in seabed morphology that would 

impact anchoring are observed within the 12,000ft radius.

No areas within the anchor radius area have the potential for sensitive sessile benthic

communities.

Seabed faults are observed to the northwest and southwest, but are not interpreted as a 

problem to anchoring.

No other features, which may impact anchor emplacement, are observed within the 12,000ft 

anchor radius.
LLOG Exploration Company Gardline Report 8025

Well Clearance Letters – Mississippi Canyon Blocks 208 & 253 – Proposed MC208-C, D and E Well Locations Volume 2

84

All anchors will be positioned using a precise DGPS system.

Charts 1, 2, and 3 illustrate an anchor radius of 12,000ft for the proposed MC208-D Location 

at 1”=1,000ft. Proposed MC208-D Location Anchor Plat (overleaf) illustrates the anchor radius

at 1”=4,000ft.
0 4,000 8,000 16,000 Feet

0 1,000 2,000 4,000 Meters

Chart scale 1" = 4,000'

Anchor Plat (MC208-D)

Proposed MC253-A Well Location

(1,204,584ft E / 10,431,637ft N)

Proposed MC253-B Well Location

(1,204,436ft E / 10,434,800ft N)

Proposed MC208-C Well Location

(1,202,630ft E / 10,439,071ft N)

3® 3

3

3

3® 3

3

3

3® 3

3

3

Depth in feet below sea surface to seabed,

contoured at 100ft intervals

±

-4800

3® 3

3

3

3® 3

3

3

3® 3

3

3

3® 3

3

3

3® 3

3

3

6

12,000ft Radius

2,000ft Radius

1,000ft Buffer Zone

Proposed MC253-A

MC252-1

Proposed MC253-B

Proposed MC208-DProposed MC208-C

Proposed MC208-E

-5000

-4900

-4800

-4700

-5100

-4600

-4500

-4400

-5200

-4300

-4200

-4100

-4900

88°24'0"W88°22'0"W88°20'0"W

28°46'0"N

28°44'0"N

1,190,0001,200,0001,210,000

10,430,000

10,440,000

10,450,000

Proposed MC208-D Well Location

(1,200,850ft E / 10,439,116ft N)

Proposed MC208-E Well Location

(1,203,299ft E, 10,446,834ft N)

3® 3

3

3

3® 3

3

3

Seabed fault intersection tick denotes

downthrown side

Upper and lower limits of escarpment
LLOG Exploration Company Gardline Report 8025

Well Clearance Letters – Mississippi Canyon Blocks 208 & 253 – Proposed MC208-C, D and E Well Locations Volume 2

86

ANCHORING ASSESSMENT – Proposed MC208-E Well Location

Proposed MC208-E Location (Surface)

Location Coordinates

NAD 27 Datum - Clarke 1866 Ellipsoid UTM Zone 16N

Latitude 28° 46' 48.01” North Easting 1,203,299 US ft E

Longitude 88° 21’ 53.74” West Northing 10,446,834 US ft N

FEL of Mississippi Canyon 208 541 US ft Inline 17451

FNL of Mississippi Canyon 208 7,566 US ft Crossline 14403

Water Depth: -4,645 ft Slope: 3.8° SE

Nearest Shoreline 49.95 Miles @ 296° 43’ 25.6’’

Port of Operation Fourchon 112.44 Miles @ 282° 58’ 56.9’’

Nearest Manned Platform MC127 A-Horn Mountain 19.63 Miles @ 73° 1’ 33.83’’

Anchor Pattern:

LLOG Exploration Company has not as yet issued a specific anchor spread to retain the 

drilling rig. The anchor radius illustrated on Plats and Charts for the proposed Block MC208-E

wellsite is the maximum predicted radius of 12,000ft plus a 1,000ft Buffer Zone. An anchorspread pattern can be designed as an addendum to this report, if required, after the drilling rig 

has been identified. The anchor pattern will be designed to avoid any infrastructure and 

potentially sensitive seabed habitats. 

Bathymetry

Water depth at the proposed MC208-E well location is -4,645ft below sea-surface. The 

seafloor deepens to the southeast at 3.8°.

Seabed Morphology, Faults and Sensitive Sessile Benthic Communities

The seabed within the radius of the proposed anchor pattern deepens to the southeast. 

The proposed well location is located upslope from an elongated mini-basin caused by subsalt uplifting to the north, south and east. Anchors could contact the escarpments surrounding 

the seabed uplifts to the north and east of the proposed location. These escarpment and uplift 

regions may exhibit slightly firmer sediment types which may reduce anchor penetration.

No areas within the anchor radius area have the potential for sensitive sessile benthic

communities.

Seabed faults are observed to the northwest and southwest, but are not interpreted to affect 

anchoring.

No other features, which may impact anchor emplacement, are observed within the 12,000ft 
LLOG Exploration Company Gardline Report 8025

Well Clearance Letters – Mississippi Canyon Blocks 208 & 253 – Proposed MC208-C, D and E Well Locations Volume 2

87

anchor radius.

All anchors will be positioned using a precise DGPS system.

Charts 1, 2, and 3 illustrate an anchor radius of 12,000ft for the proposed MC208-E Location 

at 1”=1,000ft. Proposed MC208-E Location Anchor Plat (overleaf) illustrates the anchor radius 

at 1”=4,000ft.
0 4,000 8,000 16,000 Feet

0 1,000 2,000 4,000 Meters

Chart scale 1" = 4,000'

Anchor Plat (MC208-E)

Proposed MC253-B Well Location

(1,204,436ft E / 10,434,800ft N)

Proposed MC208-C Well Location

(1,202,630ft E / 10,439,071ft N)

3® 3

3

3

3® 3

3

3

Depth in feet below sea surface to seabed,

contoured at 100ft intervals

±

-4800

3® 3

3

3

3® 3

3

3

3® 3

3

3

3® 3

3

3

3® 3

3

3

6

12,000ft Radius

2,000ft Radius

1,000ft Buffer Zone

Proposed MC253-B

Proposed MC208-C

Proposed MC208-D

Proposed MC208-E

-4300

-4400

-4500

-4600

-4800

-4700

-4200

-4100

-4000

-3900

-4900

-3800 -3700

-3600

-5000

-3500

-3400

-5100

-4100

-4300

-4100

88°20'0"W88°22'0"W88°24'0"W

28°48'0"N

28°46'0"N

1,190,0001,200,0001,210,000

10,440,000

10,450,000

10,460,000

Proposed MC208-D Well Location

(1,200,850ft E / 10,439,116ft N)

Proposed MC208-E Well Location

(1,203,299ft E, 10,446,834ft N)

3® 3

3

3

3® 3

3

3

Seabed fault intersection tick denotes

downthrown side

Area of intensive seabed faulting due

to salt uplift

Upper and lower limits of escarpment

Mississippi Canyon Block 253 (OCS-G 24062) 6/16/2011 

Mississippi Canyon Block 208 (OCS-G-32303) 

Revised Exploration Plan 7

 

APPENDIX D 

HYDROGEN SULFIDE (H2S) INFORMATION

(30 CFR Part 250.215 and 250.245) 

A. Concentration

LLOG does not anticipate encountering H2S while conducting the 

proposed exploratory operations provided for under this plan. 

B. Classification

No change – Refer to Initial EP for MC 253, OCS-G-24062 Lease and 

MC 208, OCS-G-32303, Control No. N-09406 approved on October 

22, 2009. 

• By letter dated October 23, 2009, MMS in accordance with 30 CFR 

250.490 (c) classified the area in which the proposed operations are to 

be conducted as “H2S absent”. 

C. H2S Contingency Plan

Not applicable for the proposed operations. 

D. Modeling Report

Not applicable to the proposed operations. 
Mississippi Canyon Block 253 (OCS-G 24062) 7/7/2011 

Mississippi Canyon Block 208 (OCS-G-32303) 

Revised Exploration Plan 8

 

APPENDIX E 

BIOLOGICAL, PHYSICAL AND SOCIOECONOMIC 

INFORMATION

(30 CFR Part 250.216 and 250.247) 

A. High-Density Deepwater Benthic Communities Information

Maps and analysis were submitted under separate cover with the Initial 

EP. Features or areas that could support high-density chemosynthetic 

communities are not located within 500’ of each proposed muds and 

cuttings discharge location. However, in the approval letter dated October 

23, 2009, MMS review indicates that the proposed activities are in the 

vicinity of areas that could support high-density chemosynthetic 

communities. LLOG will use a state-of-the-art positioning system on the 

anchor handling vessel to ensure that any seafloor disturbance resulting 

from the use of anchors (including that caused by the anchors, anchor 

chains, and wire ropes) does not occur within 250’ of such areas. 

LLOG will submit plats for proposed well MC 253A and proposed well 

MC 253B, which depict the “as-placed” location of all anchors with DGPS 

accuracy to the BOEMRE Gulf of Mexico OCS Region and BOEMRE 

New Orleans District offices as required in approval letter dated October 

23, 2009. 

See attached Sensitive Sessile Benthic Community Summary. 

Refer to Initial EP approval letter dated October 23, 2009 for MC 

253, OCS-G-24062 Lease and MC 208, OCS-G-32303, Control No. N09406 approved on October 22, 2009. 

B. Topographic Features Map

The activities proposed in this Plan are not affected by a topographic 

feature. 

No change – Refer to Initial EP for MC 253, OCS-G-24062 Lease and 

MC 208, OCS-G-32303, Control No. N-09406 approved on October 

22, 2009. 

C. Topographic Features Statement (Shunting)

The activities proposed in this Plan are not affected by a topographic 

feature; therefore, LLOG is not required to shunt drill cuttings and drill 

fluids. 
Mississippi Canyon Block 253 (OCS-G 24062) 6/16/2011 

Mississippi Canyon Block 208 (OCS-G-32303) 

Revised Exploration Plan 9

 

No change – Refer to Initial EP for MC 253, OCS-G-24062 Lease and 

MC 208, OCS-G-32303, Control No. N-09406 approved on October 

22, 2009. 

D. Live Bottoms (Pinnacle Trend) Map

Mississippi Canyon Blocks 253 and 208 are not located within the vicinity 

of a proposed live bottom (Pinnacle trend) area. 

No change – Refer to Initial EP for MC 253, OCS-G-24062 Lease and 

MC 208, OCS-G-32303, Control No. N-09406 approved on October 

22, 2009. 

E. Live Bottoms (Low Relief) Map

Mississippi Canyon Blocks 253 and 208 are not located within the vicinity 

of a proposed live bottom (Low Relief) area. 

No change – Refer to Initial EP for MC 253, OCS-G-24062 Lease and 

MC 208, OCS-G-32303, Control No. N-09406 approved on October 

22, 2009. 

F. Potentially Sensitive Biological Features Map

Mississippi Canyon Blocks 253 and 208 are not located within the vicinity 

of a proposed sensitive biological feature area. 

No change – Refer to Initial EP for MC 253, OCS-G-24062 Lease and 

MC 208, OCS-G-32303, Control No. N-09406 approved on October 

22, 2009. 

G. Remotely Operated Vehicle (ROV) Monitoring Survey Plan

Mississippi Canyon Blocks 253 and 208 are not located within an area 

where ROV surveys are required. 

No change – Refer to Initial EP for MC 253, OCS-G-24062 Lease and 

MC 208, OCS-G-32303, Control No. N-09406 approved on October 

22, 2009. 
Mississippi Canyon Block 253 (OCS-G 24062) 6/16/2011 

Mississippi Canyon Block 208 (OCS-G-32303) 

Revised Exploration Plan 10

 

H. Threatened or Endangered Species, Critical Habitat, and 

Marine Mammal Information. 

Proposed activities in MC 253 and 208 are not located in the presence of 

federally listed threatened or endangered species and critical habitat 

designated under the ESA and marine mammal protected under the 

MMPA. 

No change – Refer to Initial EP for MC 253, OCS-G-24062 Lease and 

MC 208, OCS-G-32303, Control No. N-09406 approved on October 

22, 2009. 

 

 I. Archaeological Report

C & C Technologies Survey Services conducted an Archaeological and 

Hazard Study for LLOG Exploration Offshore, Inc. in May, 2009 

including Mississippi Canyon Blocks 253 and 208. This survey was 

submitted to Minerals Management Service under separate cover. 

No change – Refer to Initial EP for MC 253, OCS-G-24062 Lease and 

MC 208, OCS-G-32303, Control No. N-09406 approved on October 

22, 2009.

 

J. Air and Water Quality Information

 Not applicable to proposed operations. 

No change – Refer to Initial EP for MC 253, OCS-G-24062 Lease and 

MC 208, OCS-G-32303, Control No. N-09406 approved on October 

22, 2009. 

K. Socioeconomic Information

 Not applicable to proposed operations. 

No change – Refer to Initial EP for MC 253, OCS-G-24062 Lease and 

MC 208, OCS-G-32303, Control No. N-09406 approved on October 

22, 2009. 
LLOG Exploration Company Gardline Report 8025

Well Clearance Letters – Mississippi Canyon Blocks 208 & 253 – Proposed MC253-A and B Well Locations Volume 3

66

Sensitive Sessile Benthic Community Statement – MC253-A

LLOG Exploration Company

July 1, 2011

US Department of the Interior

Minerals Management Service

1201 Elmwood Park Blvd.

New Orleans, LA 70213

Reference: Sensitive Sessile Benthic Community Summary

Mississippi Canyon, Block 253

OCS-(G 24062)

Ladies/Gentlemen:

Gardline Surveys Inc was contracted by LLOG Exploration Company to prepare a Site Clearance 

Letter for the proposed MC253-A location in Mississippi Canyon, Block 253 (OCS-G 24062). This letter 

addresses location proximity to potential sensitive sessile benthic community sites. LLOG Exploration 

Company indicates that this well will be drilled with a semi-submersible rig with anchors.

This sensitive sessile benthic community summary letter is issued as a supplement to Gardline Reports

No. 8025 entitled 3D Geohazard Assessment, Gulf of Mexico, Mississippi Canyon, Blocks MC208 and 

253, Volume 1, May 2009 and Volume 3, MC253-A and B Well Clearance Letters, July 2011. A 

Biological, Physical and Socioeconomic Map and Plat are included at the end of this appendix 

illustrating the areas of potential seabed impact.

Potential Sensitive Sessile Benthic Communities. 

Features or areas that could support high-density sensitive sessile benthic communities are not located 

within 2,000 feet of any proposed mud and cuttings discharge location.

Features or areas that could support high-density sensitive sessile benthic communities are located in 

the extreme southeast of the 12,000ft anchor radius. These regions will be avoided by at least 250ft by 

all anchoring operations.
LLOG Exploration Company Gardline Report 8025

Well Clearance Letters – Mississippi Canyon Blocks 208 & 253 – Proposed MC253-A and B Well Locations Volume 3

67

Proposed MC253-A Location (Surface)

Location Coordinates

NAD 27 Datum - Clarke 1866 Ellipsoid UTM Zone 16N

Latitude 28° 44' 17.68” North Easting 1,204,584 US ft E

Longitude 88° 21’ 37.34” West Northing 10,431,637 US ft N

FWL of Mississippi Canyon 253 744 US ft Inline 17301

FNL of Mississippi Canyon 253 6,923 US ft Crossline 14119

Water Depth: -5,042 ft Slope: 3.0° SE

Nearest Shoreline 53.99 Miles @ 298° 8’ 08.86’’

Port of Operation Fourchon 116.06 Miles @ 284° 5’ 34.73’’

Nearest Manned Platform MC127 A-Horn Mountain 20.43 Miles @ 65° 04’ 57.56’’

Nearest potential sensitive sessile benthic community to the proposed location is a localized fluid 

expulsion site approximately 10,900ft southeast of the proposed well location.

Conclusions and Recommendations: Features or areas that could support high-density sensitive 

sessile benthic communities are located in the extreme southeast of the 12,000ft anchor radius. These 

regions will be avoided by at least 250ft by all anchoring operations.

Sincerely,

LLOG Exploration Company

Jaime Mata

Geological Technician
± 3® 3

3

3

3® 3

3

3

3® 3

3

3

3® 3

3

3

3® 3

3

3

6

Proposed MC253-A

Proposed MC253-B

Proposed MC208-C

-4900

-4800

-5000

-5100

-4700

-4600

-4500

-5200

-4400

-4300

-4200

-5300

-4100

-4800

-4900

-4800

-4900 -4300

Proposed MC208-D

Proposed MC208-E

MC252-1

88°24'0"W88°23'0"W88°22'0"W88°21'0"W88°20'0"W88°19'0"W 28°46'0"N

28°45'0"N

28°44'0"N

28°43'0"N

28°42'0"N

1,190,0001,200,0001,210,0001,220,000

10,420,000

10,430,000

10,440,000

0 2,000 4,000 8,000 Feet

0 500 1,000 2,000 Meters

Chart scale 1" = 4,000'

Biological, Physical & Socio-Economic

Proposed MC208-C Well Location

(1,202,630ft E / 10,439,071ft N) 3® 3

3

3 Depth in feet below sea surface to seabed,

contoured at 100ft intervals

-4,900

Proposed MC208-D Well Location

(1,200,850ft E / 10,439,116ft N)

Proposed MC208-E Well Location

(1,203,299ft E, 10,446,834ft N)

3® 3

3

3

3® 3

3

3

MISSISSIPPI CANYON BLOCK 253 (OCS-G24062)

Proposed MC253-A Well Location

(1,204,584ft E / 10,431,637ft N)

Proposed MC253-B Well Location

(1,204,436ft E / 10,434,800ft N)

3® 3

3

3

3® 3

3

3

Seabed fault intersection tick denotes

downthrown side

Fluid expulsion sites favorable for possible 

sensitive sessile benthic community development

12,000ft Radius

1,000ft Buffer Zone

2,000ft Radius

1,000ft Buffer Zone

12,000ft Radius

2,000ft Radius
LLOG Exploration Company Gardline Report 8025

Well Clearance Letters – Mississippi Canyon Blocks 208 & 253 – Proposed MC253-A and B Well Locations Volume 3

69

Sensitive Sessile Benthic Community Statement – MC253-B

LLOG Exploration Company

July 1, 2011

US Department of the Interior

Minerals Management Service

1201 Elmwood Park Blvd.

New Orleans, LA 70213

Reference: Sensitive Sessile Benthic Community Summary

Mississippi Canyon, Block 208

OCS-(G 24062)

Ladies/Gentlemen:

Gardline Surveys Inc was contracted by LLOG Exploration Company to prepare a Site Clearance 

Letter for the proposed MC253-B location in Mississippi Canyon, Block 253, (OCS-G 24062). This 

letter addresses location proximity to potential sensitive sessile benthic community sites. LLOG 

Exploration Company indicates that this well will be drilled with a semi-submersible rig with anchors.

This sensitive sessile benthic community summary letter is issued as a supplement to Gardline Reports 

No. 8025 entitled 3D Geohazard Assessment, Gulf of Mexico, Mississippi Canyon, Blocks MC208 and 

253, Volume 1, May 2009 and Volume 3, MC253-A and B Well Clearance Letters, July 2011. A 

Biological, Physical and Socioeconomic Map and Plat are included at the end of this appendix 

illustrating the areas of potential seabed impact.

Potential Sensitive sessile benthic Communities. 

Features or areas that could support high-density sensitive sessile benthic communities are not located 

within 2,000 feet of any proposed mud and cuttings discharge location.

Features or areas that could support high-density sensitive sessile benthic communities are not located 

within the maximum anchor radius of 12,000ft.
LLOG Exploration Company Gardline Report 8025

Well Clearance Letters – Mississippi Canyon Blocks 208 & 253 – Proposed MC253-A and B Well Locations Volume 3

70

Proposed MC253-B Location (Surface)

Location Coordinates

NAD 27 Datum - Clarke 1866 Ellipsoid UTM Zone 16N

Latitude 28° 44' 48.98” North Easting 1,204,436 US ft E

Longitude 88° 21’ 39.41” West Northing 10,434,800 US ft N

FWL of Mississippi Canyon 253 596 US ft Inline 17334

FNL of Mississippi Canyon 253 3,760 US ft Crossline 14176

Water Depth: -4,922 ft Slope: 3.4° SE

Nearest Shoreline 53.99 Miles @ 298° 8’ 08.86’’

Port of Operation Fourchon 116.06 Miles @ 284° 5’ 34.73’’

Nearest Manned Platform MC127 A-Horn Mountain 20.21 Miles @ 66° 39’ 22.34’’

Nearest potential sensitive sessile benthic community to the proposed location is a localized fluid 

expulsion site approximately 12,700ft southeast of the proposed well location.

Conclusions and Recommendations: The proposed MC253-B wellsite will not impact any sites 

favorable for development of sensitive sessile benthic communities.

Sincerely,

LLOG Exploration Company

Jaime Mata

Geological Technician
± 3® 3

3

3

3® 3

3

3

3® 3

3

3

3® 3

3

3

3® 3

3

3

6

Proposed MC253-A

Proposed MC253-B

Proposed MC208-C

-4900

-4800

-5000

-5100

-4700

-4600

-4500

-5200

-4400

-4300

-4200

-5300

-4100

-4800

-4900

-4800

-4900 -4300

Proposed MC208-D

Proposed MC208-E

MC252-1

88°24'0"W88°23'0"W88°22'0"W88°21'0"W88°20'0"W88°19'0"W 28°46'0"N

28°45'0"N

28°44'0"N

28°43'0"N

28°42'0"N

1,190,0001,200,0001,210,0001,220,000

10,420,000

10,430,000

10,440,000

0 2,000 4,000 8,000 Feet

0 500 1,000 2,000 Meters

Chart scale 1" = 4,000'

Biological, Physical & Socio-Economic

Proposed MC208-C Well Location

(1,202,630ft E / 10,439,071ft N) 3® 3

3

3 Depth in feet below sea surface to seabed,

contoured at 100ft intervals

-4,900

Proposed MC208-D Well Location

(1,200,850ft E / 10,439,116ft N)

Proposed MC208-E Well Location

(1,203,299ft E, 10,446,834ft N)

3® 3

3

3

3® 3

3

3

MISSISSIPPI CANYON BLOCK 253 (OCS-G24062)

Proposed MC253-A Well Location

(1,204,584ft E / 10,431,637ft N)

Proposed MC253-B Well Location

(1,204,436ft E / 10,434,800ft N)

3® 3

3

3

3® 3

3

3

Seabed fault intersection tick denotes

downthrown side

Fluid expulsion sites favorable for possible 

sensitive sessile benthic community development

12,000ft Radius

1,000ft Buffer Zone

2,000ft Radius

1,000ft Buffer Zone

12,000ft Radius

2,000ft Radius
LLOG Exploration Company Gardline Report 8025

Well Clearance Letters – Mississippi Canyon Blocks 208 & 253 – Proposed MC208-C, D and E Well Locations Volume 2

97

Sensitive Sessile Benthic Community Statement – MC208-C

LLOG Exploration Company

July 1, 2011

US Department of the Interior

Minerals Management Service

1201 Elmwood Park Blvd.

New Orleans, LA 70213

Reference: Sensitive sessile benthic Community Summary

Mississippi Canyon, Block 208

OCS-(G 32303)

Ladies/Gentlemen:

Gardline Surveys Inc was contracted by LLOG Exploration Company to prepare a Site Clearance 

Letter for the proposed MC208-C location in Mississippi Canyon, Block 208 (OCS-G 32303). This letter 

addresses location proximity to potential sensitive sessile benthic community sites. LLOG Exploration 

Company indicates that this well will be drilled with a semi-submersible rig with anchors.

This sensitive sessile benthic community summary letter is issued as a supplement to Gardline Reports

No. 8025 entitled 3D Geohazard Assessment, Gulf of Mexico, Mississippi Canyon, Blocks MC208 and 

253, Volume 1, May 2009 and Volume 2, MC208-C, D and E Well Clearance Letters, July 2011. A 

Biological, Physical and Socio-economic Map and Plat is included at the end of this appendix illustrating 

the areas of potential seabed impact.

Potential Sensitive Sessile Benthic Communities. 

Features or areas that could support high-density sensitive sessile benthic communities are not located 

within 2,000 feet of any proposed mud and cuttings discharge location.

Features or areas that could support high-density sensitive sessile benthic communities are not located 

within the 12,000 feet maximum anchor radius.
LLOG Exploration Company Gardline Report 8025

Well Clearance Letters – Mississippi Canyon Blocks 208 & 253 – Proposed MC208-C, D and E Well Locations Volume 2

98

Proposed MC208-C Location (Surface)

Location Coordinates

NAD 27 Datum - Clarke 1866 Ellipsoid UTM Zone 16N

Latitude 28° 45' 31.07” North Easting 1,202,630 US ft E

Longitude 88° 22’ 0.25” West Northing 10,439,071 US ft N

FEL of Mississippi Canyon 208 1,210 US ft Inline 17360

FSL of Mississippi Canyon 208 511 US ft Crossline 14281

Water Depth: -4,750 ft Slope: 2.2° SE

Nearest Shoreline 49.95 Miles @ 296° 43’ 25.6’’

Port of Operation Fourchon 112.44 Miles @ 282° 58’ 56.9’’

Nearest Manned Platform MC127 A-Horn Mountain 20.23 Miles @ 69° 8’ 40.69’’

Nearest potential sensitive sessile benthic community to the proposed location is a localized fluid 

expulsion site approximately 17,000ft southeast of the proposed well location.

Conclusions and Recommendations: The proposed MC208-C wellsite will not impact any sites 

favorable for development of sensitive sessile benthic communities.

Sincerely,

LLOG Exploration Company

Jaime Mata

Geological Technician
±

3® 3

3

3

3® 3

3

3

3® 3

3

3

3® 3

3

3

3® 3

3

3

6

Proposed MC253-A

Proposed MC253-B

Proposed MC208-C

-4300

-4400

-4500

-4600

-4700

-4800

-4900

-4200

-4100

-5000

-4000

-3900

-3800 -3700

-3600

-5100

-3500

-3400

-5200

-3300

-3200

-4900

-4300

-4900

-4100

-4800

-4100

-4100

Proposed MC208-D

Proposed MC208-E

MC252-1

-3100

-4800

88°25'0"W88°24'0"W88°23'0"W88°22'0"W88°21'0"W88°20'0"W88°19'0"W

28°49'0"N

28°48'0"N

28°47'0"N

28°46'0"N

28°45'0"N

28°44'0"N

28°43'0"N

1,190,0001,200,0001,210,0001,220,000

10,430,000

10,440,000

10,450,000

10,460,000

0 2,500 5,000 10,000 Feet

0 1,000 2,000 500 Meters

Chart scale 1" = 5,000'

Biological, Physical & Socio-Economic

Proposed MC208-C Well Location

(1,202,630ft E / 10,439,071ft N) 3® 3

3

3 Depth in feet below sea surface to seabed,

contoured at 100ft intervals

-4,600

Proposed MC208-D Well Location

(1,200,850ft E / 10,439,116ft N)

Proposed MC208-E Well Location

(1,203,299ft E, 10,446,834ft N)

3® 3

3

3

3® 3

3

3

MISSISSIPPI CANYON BLOCK 208 (OCS-G32303)

Proposed MC253-A Well Location

(1,204,584ft E / 10,431,637ft N)

Proposed MC253-B Well Location

(1,204,436ft E / 10,434,800ft N)

3® 3

3

3

3® 3

3

3

Seabed fault intersection tick denotes

downthrown side

Fluid expulsion sites favorable for possible 

sensitive sessile benthic community development

12,000ft Radius

2,000ft Radius

1,000ft Buffer Zone

2,000ft Radius

1,000ft Buffer Zone

1,000ft Buffer Zone

12,000ft Radius

12,000ft Radius

2,000ft Radius
LLOG Exploration Company Gardline Report 8025

Well Clearance Letters – Mississippi Canyon Blocks 208 & 253 – Proposed MC208-C, D and E Well Locations Volume 2

100

Sensitive Sessile Benthic Community Statement – MC208-D

LLOG Exploration Company

July 1, 2011

US Department of the Interior

Minerals Management Service

1201 Elmwood Park Blvd.

New Orleans, LA 70213

Reference: Sensitive Sessile Benthic Community Summary

Mississippi Canyon, Block 208

OCS-(G 32303)

Ladies/Gentlemen:

Gardline Surveys Inc was contracted by LLOG Exploration Company to prepare a Site Clearance 

Letter for the proposed MC208-D location in Mississippi Canyon, Block 208 (OCS-G 32303). This letter 

addresses location proximity to potential sensitive sessile benthic community sites. LLOG Exploration 

Company indicates that this well will be drilled with a semi-submersible rig with anchors.

This sensitive sessile benthic community summary letter is issued as a supplement to Gardline Reports

No. 8025 entitled 3D Geohazard Assessment, Gulf of Mexico, Mississippi Canyon, Blocks MC208 and 

253, Volume 1, May 2009 and Volume 2, MC208-C, D and E Well Clearance Letters, July 2011. A 

Biological, Physical and Socioeconomic Map and Plat is included at the end of this appendix illustrating 

the areas of potential seabed impact.

Potential Sensitive Sessile Benthic Communities. 

Features or areas that could support high-density sensitive sessile benthic communities are not located 

within 2,000 feet of any proposed mud and cuttings discharge location.

Features or areas that could support high-density sensitive sessile benthic communities are not located 

within the 12,000 feet maximum anchor radius.
LLOG Exploration Company Gardline Report 8025

Well Clearance Letters – Mississippi Canyon Blocks 208 & 253 – Proposed MC208-C, D and E Well Locations Volume 2

101

Proposed MC208-D Location (Surface)

Location Coordinates

NAD 27 Datum - Clarke 1866 Ellipsoid UTM Zone 16N

Latitude 28° 45' 31.31” North Easting 1,200,850 US ft E

Longitude 88° 22’ 20.26” West Northing 10,439,116 US ft N

FEL of Mississippi Canyon 208 2,990 US ft Inline 17342

FSL of Mississippi Canyon 208 556 US ft Crossline 14312

Water Depth: -4,707 ft Slope: 1.8° SE

Nearest Shoreline 49.95 Miles @ 296° 43’ 25.6’’

Port of Operation Fourchon 112.44 Miles @ 282° 58’ 56.9’’

Nearest Manned Platform MC127 A-Horn Mountain 20.54 Miles @ 69° 30’ 5.93’’

Nearest potential sensitive sessile benthic community to the proposed location is a localized fluid 

expulsion site approximately 18,200ft southeast of the proposed well location.

Conclusions and Recommendations: The proposed MC208-D wellsite will not impact any sites 

favorable for development of sensitive sessile benthic communities.

Sincerely,

LLOG Exploration Company

Jaime Mata

Geological Technician
±

3® 3

3

3

3® 3

3

3

3® 3

3

3

3® 3

3

3

3® 3

3

3

6

Proposed MC253-A

Proposed MC253-B

Proposed MC208-C

-4300

-4400

-4500

-4600

-4700

-4800

-4900

-4200

-4100

-5000

-4000

-3900

-3800 -3700

-3600

-5100

-3500

-3400

-5200

-3300

-3200

-4900

-4300

-4900

-4100

-4800

-4100

-4100

Proposed MC208-D

Proposed MC208-E

MC252-1

-3100

-4800

88°25'0"W88°24'0"W88°23'0"W88°22'0"W88°21'0"W88°20'0"W88°19'0"W

28°49'0"N

28°48'0"N

28°47'0"N

28°46'0"N

28°45'0"N

28°44'0"N

28°43'0"N

1,190,0001,200,0001,210,0001,220,000

10,430,000

10,440,000

10,450,000

10,460,000

0 2,500 5,000 10,000 Feet

0 1,000 2,000 500 Meters

Chart scale 1" = 5,000'

Biological, Physical & Socio-Economic

Proposed MC208-C Well Location

(1,202,630ft E / 10,439,071ft N) 3® 3

3

3 Depth in feet below sea surface to seabed,

contoured at 100ft intervals

-4,600

Proposed MC208-D Well Location

(1,200,850ft E / 10,439,116ft N)

Proposed MC208-E Well Location

(1,203,299ft E, 10,446,834ft N)

3® 3

3

3

3® 3

3

3

MISSISSIPPI CANYON BLOCK 208 (OCS-G32303)

Proposed MC253-A Well Location

(1,204,584ft E / 10,431,637ft N)

Proposed MC253-B Well Location

(1,204,436ft E / 10,434,800ft N)

3® 3

3

3

3® 3

3

3

Seabed fault intersection tick denotes

downthrown side

Fluid expulsion sites favorable for possible 

sensitive sessile benthic community development

12,000ft Radius

2,000ft Radius

1,000ft Buffer Zone

2,000ft Radius

1,000ft Buffer Zone

1,000ft Buffer Zone

12,000ft Radius

12,000ft Radius

2,000ft Radius
LLOG Exploration Company Gardline Report 8025

Well Clearance Letters – Mississippi Canyon Blocks 208 & 253 – Proposed MC208-C, D and E Well Locations Volume 2

103

Sensitive Sessile Benthic Community Statement – MC208-E

LLOG Exploration Company

July 1, 2011

US Department of the Interior

Minerals Management Service

1201 Elmwood Park Blvd.

New Orleans, LA 70213

Reference: Sensitive Sessile Benthic Community Summary

Mississippi Canyon, Block 208

OCS-(G 32303)

Ladies/Gentlemen:

Gardline Surveys Inc was contracted by LLOG Exploration Company to prepare a Site Clearance 

Letter for the proposed MC208-E location in Mississippi Canyon, Block 208 (OCS-G 32303). This letter 

addresses location proximity to potential sensitive sessile benthic community sites. LLOG Exploration 

Company indicates that this well will be drilled with a semi-submersible rig with anchors.

This sensitive sessile benthic community summary letter is issued as a supplement to Gardline Report 

No. 8025 entitled 3D Geohazard Assessment, Gulf of Mexico, Mississippi Canyon, Blocks MC208 and 

253, Volume 1, May 2009 and Volume 2, MC208-C, D and E Well Clearance Letters, July 2011. A 

Biological, Physical and Socioeconomic Map and Plat is included at the end of this appendix illustrating 

the areas of potential seabed impact.

Potential Sensitive Sessile Benthic Communities. 

Features or areas that could support high-density sensitive sessile benthic communities are not located 

within 2,000 feet of any proposed mud and cuttings discharge location.

Features or areas that could support high-density sensitive sessile benthic communities are not located 

within the 12,000 feet maximum anchor radius.
LLOG Exploration Company Gardline Report 8025

Well Clearance Letters – Mississippi Canyon Blocks 208 & 253 – Proposed MC208-C, D and E Well Locations Volume 2

104

Proposed MC208-E Location (Surface)

Location Coordinates

NAD 27 Datum - Clarke 1866 Ellipsoid UTM Zone 16N

Latitude 28° 46' 48.01” North Easting 1,203,299 US ft E

Longitude 88° 21’ 53.74” West Northing 10,446,834 US ft N

FEL of Mississippi Canyon 208 541 US ft Inline 17451

FNL of Mississippi Canyon 208 7,566 US ft Crossline 14403

Water Depth: -4,645 ft Slope: 3.8° SE

Nearest Shoreline 49.95 Miles @ 296° 43’ 25.6’’

Port of Operation Fourchon 112.44 Miles @ 282° 58’ 56.9’’

Nearest Manned Platform MC127 A-Horn Mountain 19.63 Miles @ 73° 1’ 33.83’’

Nearest potential sensitive sessile benthic community to the proposed location is a localized fluid 

expulsion site approximately 22,900ft southeast of the proposed well location.

Conclusions and Recommendations: The proposed MC208-E wellsite will not impact any sites 

favorable for development of sensitive sessile benthic communities.

Sincerely,

LLOG Exploration Company

Jaime Mata

Geological Technician
±

3® 3

3

3

3® 3

3

3

3® 3

3

3

3® 3

3

3

3® 3

3

3

6

Proposed MC253-A

Proposed MC253-B

Proposed MC208-C

-4300

-4400

-4500

-4600

-4700

-4800

-4900

-4200

-4100

-5000

-4000

-3900

-3800 -3700

-3600

-5100

-3500

-3400

-5200

-3300

-3200

-4900

-4300

-4900

-4100

-4800

-4100

-4100

Proposed MC208-D

Proposed MC208-E

MC252-1

-3100

-4800

88°25'0"W88°24'0"W88°23'0"W88°22'0"W88°21'0"W88°20'0"W88°19'0"W

28°49'0"N

28°48'0"N

28°47'0"N

28°46'0"N

28°45'0"N

28°44'0"N

28°43'0"N

1,190,0001,200,0001,210,0001,220,000

10,430,000

10,440,000

10,450,000

10,460,000

0 2,500 5,000 10,000 Feet

0 1,000 2,000 500 Meters

Chart scale 1" = 5,000'

Biological, Physical & Socio-Economic

Proposed MC208-C Well Location

(1,202,630ft E / 10,439,071ft N) 3® 3

3

3 Depth in feet below sea surface to seabed,

contoured at 100ft intervals

-4,600

Proposed MC208-D Well Location

(1,200,850ft E / 10,439,116ft N)

Proposed MC208-E Well Location

(1,203,299ft E, 10,446,834ft N)

3® 3

3

3

3® 3

3

3

MISSISSIPPI CANYON BLOCK 208 (OCS-G32303)

Proposed MC253-A Well Location

(1,204,584ft E / 10,431,637ft N)

Proposed MC253-B Well Location

(1,204,436ft E / 10,434,800ft N)

3® 3

3

3

3® 3

3

3

Seabed fault intersection tick denotes

downthrown side

Fluid expulsion sites favorable for possible 

sensitive sessile benthic community development

12,000ft Radius

2,000ft Radius

1,000ft Buffer Zone

2,000ft Radius

1,000ft Buffer Zone

1,000ft Buffer Zone

12,000ft Radius

12,000ft Radius

2,000ft Radius
Mississippi Canyon Block 253 (OCS-G 24062) 6/16/2011 

Mississippi Canyon Block 208 (OCS-G-32303) 

Revised Exploration Plan 11

 

APPENDIX F 

WASTE AND DISCHARGE INFORMATION

(30 CFR PART 250.217 AND 250.248) 

A. Projected Generated Wastes

 See the following tables:

TABLE 1. Wastes you will generate, treat and downhole dispose or 

discharge to the GOM 

 TABLE 2. Wastes you will transport and /or dispose of onshore 

B. Modeling

Not applicable. Proposed activities will be covered by U.S. EPA NPDES 

General Permit. 
please specify if the amount reported is a total or per well amount

MC 208 & 253

Projected generated waste PProjected ocean discharges 

Type of Waste Composition Projected Amount TDischarge rate Discharge Method 

Will drilling occur ? If yes, fill in the muds and cuttings.

EXAMPLE: Cuttings wetted with synthetic based fluid 

Cuttings generated while using synthetic based drilling fluid. X bbl/well X bbl/day/well discharge overboard 

Water-based drilling fluid

Water based mud additives, 

barite and gel used for WBM 63,745 bbls/well 8,527 bbls/day/well Discharge overbo

Cuttings wetted with water-based fluid

Cuttings generated while using

water based drilling fluid. 3,615 bbls/well 484 bbls/day/well Discharge overbo

Cuttings wetted with synthetic-based fluid 

Cuttings generated while using 

synthetic based drilling fluid. 3,672 bbls/well 117 bbls/day/well Discharge overbo

Will humans be there? If yes, expect conventional waste

EXAMPLE: Sanitary waste water

Sanitary waste from living 

quarters X bbl/well X bbl/hr/well

chlorinate and disc

overboard 

Domestic waste Misc waste for living quarters 29,304 bbls/well 2.7 bbls/hr/well

Discharge overboard 

oil) 

Sanitary waste

Processed sanitary waste from 

living quarters 19,536 bbls/well 1.8 bbls/hr/well

Chlorinate and disc

overboard 

Is there a deck? If yes, there will be Deck Drainage

Deck Drainage

Accumulated drainage due to 

rainfall 0 to 47,261 bbls/well 0 to 167 bbls/hr/well

Test for oil and grea

discharge overbo

Will you conduct well treatment, completion, or workover? 

Well treatment fluids

NPDES approved treatment 

fluid used for well operations 100 bbls/well 20 bbls/hr/well

Test for oil and grea

discharge overbo

Well completion fluids

Clear brines used for completion

operations 500 bbls/well 100 bbls/hr/well

Test for oil and grea

discharge overboard

excludes clear br

containing Zinc 

Workover fluids N/A N/A NA NA 

TABLE 1. WASTES YOU WILL GENERATE, TREAT AND DOWNHOLE DISPOSE OR DISCHARTO THE GOM
please specify if the amount reported is a total or per well amount

MC 208 & 253

Projected generated waste PProjected ocean discharges 

Type of Waste Composition Projected Amount TDischarge rate Discharge Method 

TABLE 1. WASTES YOU WILL GENERATE, TREAT AND DOWNHOLE DISPOSE OR DISCHARTO THE GOM

Miscellaneous discharges. If yes, only fill in those associated with your activity. 

Desalinization unit discharge

Uncontaminated spent seawate

used for potable water 

generation unit 0 to 5,000 bbls/well 700 bbls/hr/well Discharge overbo

Blowout prevent fluid

Treated freshwater used control

of subsea blowout preventers 0 to 100 bbls/well 30 bbls/hr/well

Discharge at seafloo

BOP's installed 

Ballast water

Uncontaminated seawater used 

for ballast control 0 to 100,000 bbls/well 16,350 bbls/hr/well Discharge overbo

Bilge water

Uncontaminated freshwater and

seawater overflow / leakage 

accumuated from machinery 

operations 0 to 5000 bbls/well 1635 bbls/hr/well Discharge overbo

Excess cement at seafloor

Excess cement slurry and 

mixwater used for cementing 

operation - NPDES allowed 300 bbls/well 360 bbls/hr/well Discharge at mud

Fire water

Uncontaminated seawater used 

for fire control system 0 to 10,000 bbls/well 16,350 bbls/hr/well Discharge overbo

Cooling water

Uncontaminated seawater used 

for heat exchanger operations 

used to cool machinery 3,367,000 bbls/well 1542 bbls/hr/well Discharge overbo

Will you produce hydrocarbons? If yes fill in for produced water.

Produced water NA NA NA NA 

Will you be covered by an individual or general NPDES permit ? General OGMG290000

comply with the requirements of the NPDES per

NOTE: If you will not have a type of waste, enter NA in the row
Please specify whatever the amount reported is a total or per well

MC 208 & 253

Projected 

generated waste

S

olid an

d Liquid

Wastses 

Transportation

Type of Waste Composition Transport Method Name/Location of Facility Amount 

Newport Environmental Services Inc., Ingleside, TX X bbl/well 

Oil-based drilling fluid or mud N/A NA N/A NA Synthetic-based drilling fluid or mud 

Internal olifin, ester nbased mud

Barged in 25 bbls cutting boxes and / or liquid mud tanks for supply vessels

Newpark Transfer Station, Fourchon, LA 6750 bbls 

Cuttings wetted with Water-based fluid N/A NA N/A NA Cuttings wetted with Synthetic-based fluid N/A NA N/A NA Cuttings wetted with oil-based fluids N/A NA N/A NA 

Will you produce hydrocarbons? If yes fill in for produced sand.

Produced sand N/A N/A N/A N/A EXAMPLE: trash and debris (recylables) Plastic, paper, aluminum barged in a storage bin ARC, New Iberia, LA X lb/well Trash and debris Plastic, paper, aluminum Barged in a storage bin

Blanchard Landfill, Golden Meadows, LA 4000 lbs / 

Used oil Spent oil from machinery

Barged in USCG approved transfer tote tanks. L&L Services, Fourchon, LA 200 bbls / 

Wash water

Wash water w/ SBM residue and surfactants

Barged in 25 bbls cutting boxes and / or liquid mud tanks for supply vessels

Newpark Transfer Station, Fourchon, LA 2000 bbls 

Chemical product wastes

Spent treatment and / or damaged chemicals used in operations

Barged in 25 bbls cutting boxes and / or cutting boxes L&L Services, Fourchon, LA 10 bbls / w

NOTE: If you will not have a type of waste, enter NA in the row. 

TABLE 2. WASTES YOU WILL TRANSPORT AND /OR DISPOSE OF ONSHOR

Will you have additional wastes that are not permitted for discharge? If 

Waste Dis
Mississippi Canyon Block 253 (OCS-G 24062) 6/16/2011 

Mississippi Canyon Block 208 (OCS-G-32303) 

Revised Exploration Plan 12

 

APPENDIX G 

AIR EMISSIONS INFORMATION

(30 CFR PART 250.218AND 250.249) 

A. Emissions Worksheets and Screening Questions

The Projected Quality Emissions Report (Form MMS-138) addresses the 

proposed drilling, completion and potential testing operations utilizing a 

typical semi-submersible drilling unit, with related support vessels and 

construction barge information. 

As evidenced by Attachment J, the worksheets were completed based on the 

proposed flaring and burning operations. 

Screening Questions for EP’s Yes No 

Is any calculated Complete Total (CT) Emission amount (in tons associated with 

your proposed exploration activities more than 90% of the amounts calculated 

using the following formulas: CT = 3400D(2/3) for CO, and CT = 33.3D for the 

other air pollutants (where D = distance to shore in miles)? 

 X 

Does your emission calculations include any emission reduction measures or 

modified emission factors? 

 X 

Are your proposed exploration activities located east of 87.5 degrees W longitude? X 

Do you expect to encounter H2S at concentrations greater than 20 parts per million 

(ppm)? 

 X 

Do you propose to flare or vent natural gas for more than 48 continuous hours from 

any proposed well? 

 X 

Do you propose to burn produced hydrocarbon liquids? X 

B. Emissions Reduction Measures

The projected air emissions are within the exemption level; therefore, no 

emission reduction measures are being proposed. 

C. Verification of Nondefault Emissions Factors

LLOG has elected to use the default emission factors as provided in Attachment J. 

D. Non-Exempt Activities

 

The proposed activities are within the exemption amount as provided in Attachment 

J. 

E. Modeling Report 

This section of the Plan is not applicable to the proposed operations.

EXPLORATION PLAN (EP)

AIR QUALITY SCREENING CHECKLIST

OMB A

COMPANY LLOG Exploration Offshore, L.L.C.

AREA Mississippi Canyon

BLOCK 208 & 253

LEASE OCS-G 32303 & 24062

PLATFORMWELL A - E

COMPANY CONTACT Kathy GowlandTELEPHONE NO. 985-801-4300

REMARKS Drill, complete and test 5 wells.

MMS FORM MMS-138 (December 2008 - Supersedes all previous versions of form MMS-138 which may not be used). Page 1 of 8
EMISSIONS CALCULATIONS 1ST YEAR

COMPANY AREA BLOCK LEASE PLATFORM WELL CONTACT PHONE REMARKS

LLOG Exploration Offsho Mississippi Canyon 208 & 253 OCS-G 32303 & A - E Kathy Gowland 985-801-4300 

OPERATIONS EQUIPMENT RATING MAX. FUEL ACT. FUEL RUN TIME MAXIMUM POUNDS PER HOUR 

Diesel Engines HP GAL/HR GAL/D

Nat. Gas Engines HP SCF/HR SCF/D

Burners MMBTU/HR SCF/HR SCF/D HR/D DAYS PM SOx NOx VOC CO PM 

DRILLING PRIME MOVER>600hp diesel 26400 1275.12 30602.88 24 63 18.61 85.36 639.65 19.19 139.56 14.07 

PRIME MOVER>600hp diesel 0 0 0.00 0 0 0.00 0.00 0.00 0.00 0.00 0.00 PRIME MOVER>600hp diesel 0 0 0.00 0 0 0.00 0.00 0.00 0.00 0.00 0.00 PRIME MOVER>600hp diesel 0 0 0.00 0 0 0.00 0.00 0.00 0.00 0.00 0.00 BURNER diesel 0 0 0 0.00 0.00 0.00 0.00 0.00 0.00 AUXILIARY EQUIP<600hp diesel 0 0 0.00 0 0 0.00 0.00 0.00 0.00 0.00 0.00 VESSELS>600hp diesel(crew) 2100 101.43 2434.32 8 9 1.48 6.79 50.88 1.53 11.10 0.05 VESSELS>600hp diesel(supply) 2100 101.43 2434.32 10 27 1.48 6.79 50.88 1.53 11.10 0.20 VESSELS>600hp diesel(tugs) 4200 202.86 4868.64 12 4 2.96 13.58 101.76 3.05 22.20 0.07 

FACILITY DERRICK BARGE diesel 0 0 0.00 0 0 0.00 0.00 0.00 0.00 0.00 0.00 INSTALLATION MATERIAL TUG diesel 0 0 0.00 0 0 0.00 0.00 0.00 0.00 0.00 0.00 

VESSELS>600hp diesel(crew) 0 0 0.00 0 0 0.00 0.00 0.00 0.00 0.00 0.00 VESSELS>600hp diesel(supply) 0 0 0.00 0 0 0.00 0.00 0.00 0.00 0.00 0.00 MISC. BPD SCF/HR COUNTTANK- 0 0 0 0.00 

DRILLING OIL BURN 250 24 2 4.38 71.15 20.83 0.10 2.19 0.11 WELL TEST GAS FLARE 208333.33 24 2 0.12 14.87 12.56 80.94 

2011 YEAR TOTAL 28.90 183.79 878.88 37.96 267.09 14.50 

EXEMPTION 

CALCULATION

DISTANCE FROM LAND IN 

MILES 1798.20 

54.0

MMS FORM MMS-138 (December 2008 - Supersedes all previous versions of form MMS-138 which may not be used). Page 3 of 8
EMISSIONS CALCULATIONS 2ND YEAR

COMPANY AREA BLOCK LEASE PLATFORM WELL CONTACT PHONE REMARKS

LLOG Exploration OffshoMississippi Canyon 208 & 253 OCS-G 32303 & A - E Kathy Gowland 985-801-4300 

OPERATIONS EQUIPMENT RATING MAX. FUEL ACT. FUEL RUN TIME MAXIMUM POUNDS PER HOUR 

Diesel Engines HP GAL/HR GAL/D

Nat. Gas Engines HP SCF/HR SCF/D

Burners MMBTU/HR SCF/HR SCF/D HR/D DAYS PM SOx NOx VOC CO PM S

DRILLING PRIME MOVER>600hp diesel 26400 1275.12 30602.88 24.00 91.00 18.61 85.36 639.65 19.19 139.56 20.32 9

PRIME MOVER>600hp diesel 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0PRIME MOVER>600hp diesel 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0PRIME MOVER>600hp diesel 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0BURNER diesel 0 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0AUXILIARY EQUIP<600hp diesel 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0VESSELS>600hp diesel(crew) 2100 101.43 2434.32 8.00 14.00 1.48 6.79 50.88 1.53 11.10 0.08 0VESSELS>600hp diesel(supply) 2100 101.43 2434.32 10.00 40.00 1.48 6.79 50.88 1.53 11.10 0.30 1VESSELS>600hp diesel(tugs) 4200 202.86 4868.64 12.00 6.00 2.96 13.58 101.76 3.05 22.20 0.11 0

FACILITY DERRICK BARGE diesel 0 0 0.00 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0INSTALLATION MATERIAL TUG diesel 0 0 0.00 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0

VESSELS>600hp diesel(crew) 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0VESSELS>600hp diesel(supply) 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0MISC. BPD SCF/HR COUNTTANK- 0 0 0 0.00 

DRILLING OIL BURN 250 24 4 4.38 71.15 20.83 0.10 2.19 0.21 3WELL TEST GAS FLARE 208333.33 24 4 0.12 14.87 12.56 80.94 0

2012 YEAR TOTAL 28.90 183.79 878.88 37.96 267.09 21.02 9

EXEMPTION 

CALCULATION

DISTANCE FROM LAND IN 

MILES 1798.20 17

54.0

MMS FORM MMS-138 (December 2008 - Supersedes all previous versions of form MMS-138 which may not be used). Page 4 of 8
EMISSIONS CALCULATIONS 3RD YEAR

COMPANY AREA BLOCK LEASE PLATFORM WELL CONTACT PHONE REMARKS

LLOG Exploration OffshoMississippi Canyon 208 & 253 OCS-G 32303 & A - E Kathy Gowland 985-801-4300 

OPERATIONS EQUIPMENT RATING MAX. FUEL ACT. FUEL RUN TIME MAXIMUM POUNDS PER HOUR 

Diesel Engines HP GAL/HR GAL/D

Nat. Gas Engines HP SCF/HR SCF/D

Burners MMBTU/HR SCF/HR SCF/D HR/D DAYS PM SOx NOx VOC CO PM S

DRILLING PRIME MOVER>600hp diesel 26400 1275.12 30602.88 24 141 18.61 85.36 639.65 19.19 139.56 31.48 14

PRIME MOVER>600hp diesel 0 0 0.00 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0PRIME MOVER>600hp diesel 0 0 0.00 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0PRIME MOVER>600hp diesel 0 0 0.00 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0BURNER diesel 0 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0AUXILIARY EQUIP<600hp diesel 0 0 0.00 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0VESSELS>600hp diesel(crew) 2100 101.43 2434.32 8 21 1.48 6.79 50.88 1.53 11.10 0.12 0VESSELS>600hp diesel(supply) 2100 101.43 2434.32 10 61 1.48 6.79 50.88 1.53 11.10 0.45 2VESSELS>600hp diesel(tugs) 4200 202.86 4868.64 12 9 2.96 13.58 101.76 3.05 22.20 0.16 0

FACILITY DERRICK BARGE diesel 0 0 0.00 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0INSTALLATION MATERIAL TUG diesel 0 0 0.00 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0

VESSELS>600hp diesel(crew) 0 0 0.00 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0VESSELS>600hp diesel(supply) 0 0 0.00 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0MISC. BPD SCF/HR COUNT

TANK- 0 0 0 0.00 

DRILLING OIL BURN 250 24 6 4.38 71.15 20.83 0.10 2.19 0.32 5WELL TEST GAS FLARE 208333.33 24 6 0.12 14.87 12.56 80.94 0

2013 YEAR TOTAL 28.90 183.79 878.88 37.96 267.09 32.54 15

EXEMPTION 

CALCULATION

DISTANCE FROM LAND IN 

MILES 1798.20 17

54.0

MMS FORM MMS-138 (December 2008 - Supersedes all previous versions of form MMS-138 which may not be used). Page 5 of 8
EMISSIONS CALCULATIONS 4TH YEAR

COMPANY AREA BLOCK LEASE PLATFORM WELL CONTACT PHONE REMARKS

LLOG Exploration Offshor Mississippi Canyon 208 & 253 OCS-G 32303 & A - E Kathy Gowland 985-801-4300 

OPERATIONS EQUIPMENT RATING MAX. FUEL ACT. FUEL RUN TIME MAXIMUM POUNDS PER HOUR 

Diesel Engines HP GAL/HR GAL/D

Nat. Gas Engines HP SCF/HR SCF/D

Burners MMBTU/HR SCF/HR SCF/D HR/D DAYS PM SOx NOx VOC CO PM 

DRILLING PRIME MOVER>600hp diesel 26400 1275.12 30602.88 25 196 18.61 85.36 639.65 19.19 139.56 45.59 

PRIME MOVER>600hp diesel 0 0 0.00 0 0 0.00 0.00 0.00 0.00 0.00 0.00 PRIME MOVER>600hp diesel 0 0 0.00 0 0 0.00 0.00 0.00 0.00 0.00 0.00 PRIME MOVER>600hp diesel 0 0 0.00 0 0 0.00 0.00 0.00 0.00 0.00 0.00 BURNER diesel 0 0 0 0.00 0.00 0.00 0.00 0.00 0.00 AUXILIARY EQUIP<600hp diesel 0 0 0.00 0 0 0.00 0.00 0.00 0.00 0.00 0.00 VESSELS>600hp diesel(crew) 2100 101.43 2434.32 8 29 1.48 6.79 50.88 1.53 11.10 0.17 VESSELS>600hp diesel(supply) 2100 101.43 2434.32 10 85 1.48 6.79 50.88 1.53 11.10 0.63 VESSELS>600hp diesel(tugs) 4200 202.86 4868.64 12 13 2.96 13.58 101.76 3.05 22.20 0.23 

FACILITY DERRICK BARGE diesel 0 0 0.00 0 0 0.00 0.00 0.00 0.00 0.00 0.00 INSTALLATION MATERIAL TUG diesel 0 0 0.00 0 0 0.00 0.00 0.00 0.00 0.00 0.00 

VESSELS>600hp diesel(crew) 0 0 0.00 0 0 0.00 0.00 0.00 0.00 0.00 0.00 VESSELS>600hp diesel(supply) 0 0 0.00 0 0 0.00 0.00 0.00 0.00 0.00 0.00 MISC. BPD SCF/HR COUNT

TANK- 0 0 0 0.00 

DRILLING OIL BURN 250 24 7 4.38 71.15 20.83 0.10 2.19 0.37 WELL TEST GAS FLARE 208333.33 24 7 0.12 14.87 12.56 80.94 

2014 YEAR TOTAL 28.90 183.79 878.88 37.96 267.09 46.99 

EXEMPTION 

CALCULATION

DISTANCE FROM LAND IN 

MILES 1798.20 

54.0

MMS FORM MMS-138 (December 2008 - Supersedes all previous versions of form MMS-138 which may not be used). Page 6 of 8
SUMMARY

COMPANY AREA BLOCK LEASE PLATFORM WELLLLOG ExploratioMississippi Canyon 208 & 253 OCS-G 32303 & 24062 A - E

Emitted Substance

Year

 PM SOx NOx VOC CO

2011 14.50 67.73 495.57 15.14 109.932012 21.02 98.87 716.90 22.06 160.032013 32.54 152.94 1110.14 34.14 247.642014 46.99 219.86 1605.60 49.14 356.64

Allowable 1798.20 1798.20 1798.20 1798.20 48574.47

MMS FORM MMS-138 (December 2008 - Supersedes all previous versions of form MMS-138 which may not be used). Page 8 of 8
Mississippi Canyon Block 253 (OCS-G 24062) 6/16/2011 

Mississippi Canyon Block 208 (OCS-G-32303) 

Revised Exploration Plan 13

 

 APPENDIX H 

OIL SPILL INFORMATION

(30 CFR PART 250.219 AND 250.250)

A. Oil Spill Response Planning

All the proposed activities in this Revised Exploration Plan will be covered by the 

Oil Spill Response Plan filed by LLOG (MMS Operator No. 02058) in 

accordance with 30 CFR 254 and approved on June 3, 2009, last modification 

May 31, 2011 (not currently approved). LLOG submitted the Biennial Oil Spill 

Response Plan on 06/30/2010 (currently pending approval). OSRP Certification 

submitted by letter dated June 1, 2011 for modification dated May 31, 2011. The 

WCD proposed in this Plan does not exceed the WCD submitted in the 

modification dated 05/31/2011. The last OSRP Certification was accepted by 

BOEMRE on 03/25/2011. 

B. Spill Response Sites

The following locations will be used in the event an oil spill occurs as a result of 

the proposed activities. 

Primary Response Equipment 

Location 

Pre-Planned Staging Location(s) 

Houma, LA Fort Jackson, LA 

C. OSRO Information

The O’Brien Group (TOG) will provide trained personnel capable of providing 

supervisory management of the oil spill response in addition to contacting and 

deploying cleanup personnel and equipment 

LLOG utilizes Clean Gulf Associates (CGA) as it’s primary provider for 

equipment, which is an industry cooperative owning an inventory of oil spill 

clean-up equipment. CGA is supported by the Marine Spill Response 

Corporation’s (MSRC), which is responsible for storing, inspecting, maintaining 

and dispatching CGA’s equipment. The MSRC STARS network provides for the 

closest available personnel, as well as an MSRC supervisor to operate the 

equipment. 
Mississippi Canyon Block 253 (OCS-G 24062) 7/13/2011 

Mississippi Canyon Block 208 (OCS-G-32303) 

Revised Exploration Plan 14

 

D. Worst-Case Scenario Information

Category Regional OSRP Revised EP 

Type of Activity Exploratory MODU Exploratory MODU 

Facility Surface Location Mississippi Canyon Block 547 Mississippi Canyon Blocks 253 

& 208 

Facility Description Well Location Well No. SS002 

(Location B) 

Well No. 001 (Location B) 

Distance to Nearest Shoreline 

(Miles) 38.4 miles 54 miles 

Volume: 

 Storage Tanks (total) 

 Facility Piping (total) 

 Lease Term Pipeline 

 Uncontrolled Blowout (day) 

 Barging 

Potential 24 Hour Volume 

(bbls) 

Total Volume 

225,144 bbls 

22,289,256 

 

190,525 bbls 

21,719,850 

Type of Liquid Hydrocarbon Crude Oil Crude Oil 

API Gravity 28o 38.2o 

Since LLOG Exploration Offshore, L.L.C. (LLOG) has the capability to respond 

to the appropriate worst-case spill scenario included in its regional OSRP 

approved on June 3, 2009, last modified May 31, 2011 (not currently approved), 

and since the worst-case scenario determined for this EP does not replace the 

worst-case scenario in our modified Regional OSRP (May 31, 2011), I hereby 

certify that LLOG has the capability to respond, to the maximum extent 

practicable, to a worst-case discharge, or a substantial threat of such a discharge, 

resulting from the activities proposed in this EP. 

LLOG submitted the Biennial Oil Spill Response Plan on 06/30/2010 (currently 

pending approval). OSRP Certification submitted by letter dated June 1, 2011 for 

modification dated May 31, 2011. The WCD proposed in this Plan does not 

exceed the WCD submitted in the modification dated 05/31/2011. The last OSRP 

Certification was accepted by BOEMRE on 03/25/2011. 

LLOG Exploration Offshore, L.L.C., Company No. 02058, previously submitted 

the Regional OSRP Exploration WCD volume to be reviewed in Plan R-5139, 

Revised Exploration Plan submitted on March 2, 2011. 

 

The required proprietary data outlined in NTL 2010-N06 was submitted to 

BOEMRE under cover letter dated June 13, 2011. LLOG accepts the BOEMRE’s 

worst case discharge value of 190,525 bbls potential 24 hour volume with a 38.2o 

API Gravity. 

E. Oil Spill Response Discussion

See the following Oil Spill Response Discussion. 
SPILL RESPONSE DISCUSSION 

For the purpose of NEPA and Coastal Zone Management Act analysis, the largest spill volume 

originating from the proposed activity would be a well blowout during drilling operations, 

estimated to be 190,525 barrels of crude oil with an API gravity of 38.2°. 

Land Segment and Resource Identification

Trajectories of a spill and the probability of it impacting a land segment have been projected 

utilizing information in the BOEM Oil Spill Risk Analysis Model (OSRAM) for the Central and 

Western Gulf of Mexico available on the BOEM website. The results are shown in Figure 1.

The BOEM OSRAM identifies a 21% probability of impact to the shorelines of Plaquemines 

Parish, LA within 30 days. Plaquemines Parish includes Barataria Bay, the Mississippi River 

Delta, Breton Sound and the affiliated islands and bays. This region is an extremely sensitive 

habitat, and serves as a migratory, breeding, feeding and nursery habitat for numerous species of 

wildlife. Beaches in this area vary in grain particle size, and can be classified as fine sand, shell 

or perched shell beaches. Sandy and muddy tidal flats are also abundant. 

Response

LLOG Exploration Offshore, L.L.C. will make every effort to respond to the Worst Case 

Discharge as effectively as practicable. A description of the response equipment available to 

contain and recover the Worst Case Discharge is shown in Figure 2. 

Using the estimated chemical and physical characteristics of crude oil, an ADIOS weathering 

model was run on a similar product from the ADIOS oil database. The results indicate 25% or 

47,631 barrels of crude oil would be evaporated/dispersed within 24 hours, with 142,894 barrels 

remaining. 

Spill Response MC 253 Barrels of Oil 

WCD Volume 190,525 

Less 25% natural evaporation/dispersion 47,631 

Remaining volume 142,894 

Oil addressed by aerial dispersants 7,540 

Oil addressed by in-situ burning 7,144 

Figure 2 outlines equipment, personnel, materials and support vessels as well as temporary 

storage equipment available to respond to a spill of 190,525 barrels. The list estimates individual 

times needed for procurement, load out, travel time to the site and deployment. Figure 2 also 

indicates how operations will be supported. 
If aerial dispersants are utilized, 8 sorties (9,600 gallons) from two of the DC-3 aircrafts and 4 

sorties (8,000 gallons) from the Basler aircraft should disperse approximately 7,540 barrels of 

product. If the conditions are favorable for in-situ burning, the proper approvals have been 

obtained and the proper planning is in place, in-situ burning of oil may be attempted. Using 

estimates based on the Deepwater Horizon spill of 2010, up to 5% or 5,439 barrels of the Worst 

Case Discharge volume (remaining after natural weathering) could be burned. Slick containment 

boom would be immediately called out and on-scene as soon as possible. Offshore response 

strategies may include attempting to skim utilizing the HOSS Barge, nine Fast Response Units, 

two Aqua Guard Triton RBS skimmers, and eleven sets of Koseq skimming arms, with a total 

derated skimming capacity of 318,609 barrels. Temporary storage associated with skimming 

equipment equals 31,700 barrels. If additional storage is needed, an 80,000 barrel storage barge, 

an 83,937 barrel storage barge, an 86,948 barrel storage barge, and a 107,285 barrel storage 

barge may be mobilized and centrally located to provide temporary storage allowing the 

skimmers to stay in the area of operations as much as possible. Safety is first priority. Air 

monitoring will be accomplished and operations deemed safe prior to any 

containment/skimming attempts. 

If the spill went unabated, shoreline impact in Plaquemines Parish, Louisiana would depend 

upon existing environmental conditions. Shoreline protection would include the use of CGA’s 

near shore and shallow water skimmers with a totaled derated skimming capacity of 54,753 

barrels. Temporary storage associated with skimming equipment equals 1,861 barrels. If 

additional storage is needed, an 86,948 barrel storage barge may be mobilized and centrally 

located to provide temporary storage allowing the skimmers to stay in the area of operations as 

much as possible. Onshore response may include the deployment of shoreline boom on beach 

areas, or protection and sorbent boom on vegetated areas. MSAs with AMPOL and Oil Mop will 

ensure the availability of 147,000 feet of 18” shoreline boom. Figure 2 outlines individual times 

needed for procurement, load out, travel time to the site and deployment. Strategies would be 

based upon surveillance and real time trajectories that depict areas of potential impact given 

actual sea and weather conditions. The State of Louisiana Initial Oil Spill Response Plan for 

Plaquemines Parish and Unified Command would be consulted to ensure that environmental and 

special economic resources would be correctly identified and prioritized to ensure optimal 

protection. Shoreline protection strategies depict the protection response modes applicable for oil 

spill clean-up operations. The State of Louisiana Initial Oil Spill Response Plan provides detailed 

shoreline protection strategies for this area, and it describes necessary action to keep the oil spill 

from entering Louisiana’s coastal wetlands, based on the assumption that removal of the released 

oil will be much easier and less damaging to fragile coastal ecosystems if done in the open 

waters of the Gulf of Mexico. Supervisory personnel have the option to modify the deployment 

and operation of equipment allowing a more effective response to site-specific circumstances. 

LLOG Exploration Offshore, L.L.C.’s contract Spill Management Team holds a copy of the 

State of Louisiana Initial Oil Spill Response Plan. 
Initial Response Considerations 

Actual actions taken during an oil spill response will be based on many factors to include but not 

be limited to: 

• Weather 

• Equipment and materials availability 

• Ocean currents and tides 

• Location of the spill 

• Product spilled 

• Amount spilled 

• Environmental risk assessments 

• Trajectory and product analysis 

• Well status, i.e., shut in or continual release 

LLOG Exploration Offshore, L.L.C. will take action to provide a safe, aggressive response to 

contain and recover as much of the spilled oil as quickly as it is safe to do so. In an effort to 

protect the environment, response actions will be designed to provide an “in-depth” protection 

strategy meant to recover as much oil as possible as far from environmentally sensitive areas as 

possible. Safety will take precedence over all other considerations during these operations. 

Upon notification of a spill, the following actions will be taken: 

• Information will be confirmed 

• An assessment will be made and initial objectives set 

• OSROs and appropriate agencies will be notified 

• ICS 201, Initial Report Form completed 

• Initial Safety plan will be written and published 

• Unified Command will be established 

o Overall safety plan developed to reflect the operational situation and coordinated 

objectives 

o Areas of responsibility established for Source Control and each surface operational 

site 

o On-site command and control established 

Offshore Response Actions 

Equipment Deployment

Surveillance 

• Surveillance Aircraft: within two hours of QI notification, or at first light

• Provide trained observer to provide on site status reports 

• Provide command and control platform at the site if needed 

• Continual surveillance of oil movement by remote sensing systems, aerial photography 

and visual confirmation 

• Continual monitoring of vessel assets using vessel monitoring systems 
Dispersant application assets 

• Put ASI on standby 

• With the FOSC, conduct analysis to determine appropriateness of dispersant application 

• Gain FOSC approval for use of dispersants on the surface 

• Deploy aircraft in accordance with a plan developed for the actual situation 

• Coordinate movement of dispersants, aircraft, and support equipment and personnel 

• Confirm dispersant availability for current and long range operations 

• Start ordering dispersant stocks required for expected operations 

Containment boom 

• Call out early and expedite deployment to be on scene ASAP 

• Ensure boom handling and mooring equipment is deployed with boom 

• Provide continuing reports to vessels to expedite their arrival at sites that will provide for 

their most effective containment 

• Use Vessels of Opportunity (VOO) to deploy and maintain boom 

Dedicated off-shore skimming systems 

General 

• Deployed to the highest concentration of oil 

• Assets deployed at safe distance from aerial dispersant and in-situ burn operations 

CGA HOSS Barge 

• Use in areas with heaviest oil concentrations 

• Consider for use in areas of known debris (seaweed, and other floating materials) 

CGA FRUs 

• To the area of the thickest oil 

• Use as far off-shore as allowed 

T&T Koseq Skimming Systems 

• To the area of the thickest oil 

• Use as far off-shore as allowed 

• VOOs with a minimum of 2,000 bbls storage capacity 

Storage Vessels 

• Establish availability of CGA contracted assets 

• Early call out (to allow for tug boat acquisition and deployment speeds) 

• Phase mobilization to allow storage vessels to arrive at the same time as skimming 

systems 

• Position as closely as possible to skimming assets to minimize offloading time 
Vessels of Opportunity (VOO) 

• Use LLOG Exploration Offshore, L.L.C.’s contracted resources as applicable 

• Industry vessels are usually best for deployment of Vessel of Opportunity Skimming 

Systems (VOSS) 

• Acquire additional resources as needed 

• Consider use of local assets, i.e. fishing and pleasure craft 

• Expect mission specific and safety training to be required 

• Plan with the US Coast Guard for vessel inspections 

In-situ Burn assets 

• Determine appropriateness of in-situ burn operation in coordination with the FOSC and 

affected SOSC 

• Determine availability of fire boom and selected ignition systems 

• Start ordering fire boom stocks required for expected operations 

• Contact boom manufacturer to provide training if required 

• Determine assets to perform on water operation 

• Build operations into safety plan 

• Conduct operations in accordance with an approved plan 
Near Shore Response Actions 

Timing 

• Put near shore assets on standby and deployment in accordance with planning based on 

the actual situation, actual trajectories and oil budgets 

• VOO identification and training in advance of spill nearing shoreline if possible 

• Outfitting of VOOs for specific missions 

• Deployment of assets based on actual movement of oil 

Considerations 

• Water depth, vessel draft 

• Shoreline gradient 

• State of the oil 

• Use of VOOs 

• Distance of surf zone from shoreline 

Equipment Deployment 

Surveillance 

• Provide trained observer to direct skimming operations 

• Continual surveillance of oil movement by remote sensing systems, aerial photography 

and visual confirmation 

• Continual monitoring of vessel assets 

Dispersant Use 

• Generally will not be approved within 3 miles of shore or with less than 10 meters of 

water depth 

• Approval would be at Regional Response Team level (Region 6) 

Vessel Deployment 

Dedicated Near Shore skimming systems 

• FRVs 

• Egmopol and Marco SWS 

• Operate with aerial spotter directing systems to observed oil slicks 

VOO 

• Use LLOG Exploration Offshore, L.L.C.’s contracted resources as applicable 

• Industry vessel are usually best for deployment of Vessel of Opportunity Skimming 

Systems (VOSS) 

• Acquire additional resources as needed 

• Consider use of local assets, i.e. fishing and pleasure craft 

• Expect mission specific and safety training to be required 

• Plan with the US Coast Guard for vessel inspections 

• Operate with aerial spotter directing systems to oil patches 
Shoreline Protection Operations 

Response Planning Considerations 

• Environmental risk assessments (ERA) to determine priorities for area protection 

• Time to acquire personnel and equipment and their availability 

• Previous contingency planning contained in the appropriate Area Contingency 

Plan, and currently (Feb 2011) for Louisiana, The State of Louisiana Initial Oil Spill 

Response Plan, Deep Water Horizon, dated 2 May 2010 (La. OSRP)

Actions 

Placement of boom 

• Position boom in accordance with the ERA based on the actual situation or the 

appropriate ACP 

• Assess timing of booming operations to ensure it is where it needs to be at time of 

impact. Consider: 

o Trajectories 

o Weather forecast 

o Oil Impact forecast 

o Verified spill movement 

o Boom, manpower and vessel (shallow draft) availability 

o Near shore boom and support material, (stakes, anchors, line) 

Beach Preparation 

Considerations and Actions 

• Use of a 10 mile go/no go line to determine timing of beach cleaning 

• Shoreline Cleanup and Assessment Team Reports and recommendations 

• Determination of Archeological sites and gaining authority to enter 

• Monitoring of tide tables and weather to determine extent of high tides 

• Pre cleaning of beaches by moving waste above high time lines to minimize waste 

• Staging of equipment and housing of response personnel as close to the job site as 

possible to maximize on-site work time 

• Boom tending, repair, replacement and security (use of local assets may be advantageous) 

• Constant awareness of weather and oil movement for resource redeployment as necessary 

• In-situ burn may be considered when marshes have been impacted 

• Passive clean up of marshes should considered and appropriate stocks of sorbent boom 

and/or sweep obtained 

• Earthen berms and shoreline protection boom may be considered to protect sensitive 

inland areas 
Decanting Strategy 

Recovered oil and water mixtures will typically separate into distinct phases when left in a 

quiescent state. When separation occurs, the relatively clean water phase can be siphoned or 

decanted back to the recovery point with minimal, if any, impact. Decanting therefore increases 

the effective on-site oil storage capacity and equipment operating time. FOSC/SOSC approval 

will be requested prior to decanting operations. This practice is routinely used for oil spill 

recovery. 

CGA Equipment Limitations 

The capability for any spill response equipment, whether a dedicated or portable system, to 

operate in differing weather conditions will be directly in relation to the capabilities of the vessel 

the system in placed on. Most importantly, however, the decision to operate will be based on the 

judgment of the Unified Command and/or the Captain of the vessel, who will ultimately have the 

final say in terminating operations. Skimming equipment listed below may have operational 

limits which exceed those safety thresholds. As was seen in the Deepwater Horizon (DWH) oil 

spill response, vessel skimming operations ceased when seas reached 5-6 feet and vessels were 

often recalled to port when those conditions were exceeded. Systems below are some of the 

most up-to-date systems available and were employed during the DWH spill. 

Boom 3 foot seas, 20 knot winds 

Dispersants Winds more than 25 knots 

Visibility less than 3 nautical miles 

Ceiling less than 1,000 feet. 

FRU 8 foot seas 

HOSS Barge/OSRB 8 foot seas 

Koseq Arms 8 foot seas 

OSRV 4 foot seas 
Environmental Conditions in the GOM

Louisiana is situated between the easterly and westerly wind belts, and therefore, experiences 

westerly winds during the winter and easterly winds in the summer. Average wind speed is 

generally 14-15 mph along the coast. Wave heights average 4 and 5 feet. However, during 

hurricane season, Louisiana has recorded wave heights ranging from 40 to 50 feet high and 

winds reaching speeds of 100 mph. Because much of southern Louisiana lies below sea level, 

flooding is prominent. 

Surface water temperature ranges between 70 and 80 ̊F during the summer months. During the 

winter, the average temperature will range from 50 and 60 ̊F. 

The Atlantic and Gulf of Mexico hurricane season is officially from 1 June to 30 November. 

97% of all tropical activity occurs within this window. The Atlantic basin shows a very peaked 

season from August through October, with 78% of the tropical storm days, 87% of the minor 

(Saffir-Simpson Scale categories 1 and 2) hurricane days, and 96% of the major (Saffir-Simpson 

categories 3, 4 and 5) hurricane days occurring then. Maximum activity is in early to mid 

September. Once in a few years there may be a hurricane occurring "out of season" - primarily in 

May or December. Globally, September is the most active month and May is the least active 

month. 
FIGURE 1 

TRAJECTORY BY LAND SEGMENT 

Trajectory of a spill and the probability of it impacting a land segment have been projected utilizing LLOG 

Exploration Offshore, L.L.C.’s WCD and information in the BOEM Oil Spill Risk Analysis Model 

(OSRAM) for the Central and Western Gulf of Mexico available on the BOEM website using 30 day 

impact. The results are tabulated below. 

Area/Block OCS-G Launch 

Area Land Segment and/or Resource Conditional Probability (%) within 30 days 

Mississippi Canyon 253 

Loc B 

54 miles from shore 

G24062 C57 Cameron Parish, LA 

Vermilion Parish, LA 

Terrebonne Parish, LA 

Lafourche Parish, LA 

Plaquemines Parish, LA 

St. Bernard Parish, LA 

Hancock & Harrison County, MS 

Jackson County, MS 

Mobile County, AL 

Baldwin County, AL 

Escambia County, FL 

Okaloosa County, FL 

Walton County, FL 

Bay County, FL 

1 

1 

2 

2 

21 

3 

1 

1 

1 

1 

1 

1 

1 

1 
WCD Scenario– BASED ON WELL BLOWOUT DURING DRILLING OPERATIONS (54 miles from sh

190,525 bbls of crude oil API Gravity 38.2° 

FIGURE 2 – Equipment Response Time to MC 253 Loc B 

Dispersant/Surveillance Dispersant Capacity (gal) Storage Capacity Persons Req. From Hrs to Procure Hrs to Loadout Travel to site 

CGA 

Basler 67T 2000 NA 2 Houma 1 1 0.8 

ASI 

DC 3 1200 NA 2 Houma 1 1 1.0 DC 3 1200 NA 2 Houma 1 1 1.0 Aero Commander NA NA 2 Houma 1 1 0.8 

Offshore Response 

Offshore Equipment No 

Staging EDRC Storage Capacity VOO Persons Required From Hrs to Procure Hrs to Loadout Hrs to GOM 

CGA 

HOSS Barge 43000 4000 3 Tugs 8 Harvey 4 0 5 

T&T Marine (available through contract with CGA) 

Koseq Skimming Arms (3) 53487 6000 3 Utility 18 Leeville 4 12 1 Koseq Skimming Arms (2) 35658 4000 2 Utility 12 Venice 4 12 1 Koseq Skimming Arms (1) 17829 2000 1 Utility 6 Fourchon 4 12 1 Koseq Skimming Arms (5) 89145 10000 5 Utility 30 Galveston 4 12 1 

Recovered Oil Storage No 

Staging EDRC Storage Capacity VOO Persons Required From Hrs to Procure Hrs to Loadout Hrs to GOM 

K-Sea Operating (available through contract with CGA) 

PACIFIC 996165 NA 80000 1 Tug 6 Venice 4 12 4 DBL 76 1212984 NA 83937 1 Tug 6 Venice 4 12 4 DBL 81 1132231 NA 86948 1 Tug 6 Venice 4 12 4 DBL 101 1119760 NA 107285 1 Tug 6 Venice 4 12 4 
Staging Area: Venice 

Offshore Equipment With 

Staging EDRC Storage Capacity VOO Persons Req. From Hrs to Procure Hrs to Loadout Travel to Staging 

CGA 

FRU (1) + 100 bbl Tank (2) 3770 200 1 Utility 6 Belle Chasse 1 2 2 FRU (1) + 100 bbl Tank (2) 3770 200 1 Utility 6 Galveston 1 2 8 FRU (3) + 100 bbl Tank (5) 11310 500 1 Utility 6 Houma 1 2 3 FRU (1) + 100 bbl Tank (2) 3770 200 1 Utility 6 Ingleside 1 2 11 FRU (1) + 100 bbl Tank (2) 3770 200 1 Utility 6 Lake Charles 1 2 5.5 FRU (2) + 100 bbl Tank (4) 7540 400 1 Utility 6 Venice 1 2 0 Aqua Guard Triton RBS (2) 45560 4000 2 Utility 12 Galveston 4 12 8 

Offshore Equipment With 

Staging EDRC Storage Capacity VOO Persons Req. From Hrs to Procure Hrs to Loadout Travel to Staging 

CGA 

42” Auto Boom (5000’) NA NA 10 Crew 20 Belle Chasse 1 2 2 42” Auto Boom (5000’) NA NA 10 Crew 20 Galveston 1 2 8 42” Auto Boom (5000’) NA NA 10 Crew 20 Houma 1 2 3 42” Auto Boom (2500’) NA NA 6 Crew 12 Ingleside 1 2 11 42” Auto Boom (5000’) NA NA 10 Crew 20 Lake Charles 1 2 5.5 42” Auto Boom (2500’) NA NA 6 Crew 12 Pascagoula 1 2 4 1000’ Hydro-Fire Boom (In-Situ Burn) NA NA 8 Utility 40 Harvey 1 4 2 
Nearshore Response 

Nearshore Equipment No 

Staging EDRC Storage Capacity VOO Persons Required From Hrs to Procure Hrs to Loadout Hrs to GOM 

K-Sea Operating (available through contract with CGA) 

DBL 82 1137538 NA 86948 1 Tug 6 Venice 4 12 4 

CGA 

46’ FRV 5000 65 NA 4 Galveston 1 0 0 46’ FRV 5000 65 NA 4 Houma 1 0 2 46’ FRV 5000 65 NA 4 Lake Charles 1 0 1 46’ FRV 5000 65 NA 4 Venice 1 0 1 Trinity SWS 21500 249 NA 4 Morgan City 1 2 2 

Staging Area: Venice 

Nearshore and Inland 

Skimmers With Staging EDRC Storage Capacity VOO Persons Req. From Hrs to Procure Hrs to Loadout Travel to Staging T

De

CGA 

SWS Egmopol 3000 100 NA 3 Galveston 1 2 8 SWS Egmopol 3000 100 NA 3 Houma 1 2 3 SWS Marco 3588 34 NA 3 Houma 1 2 3 SWS Marco 3588 20 NA 3 Lake Charles 1 2 5.5 Rope Mop 77 2 0 3 Belle Chasse 1 2 2 RO Storage Barge NA 249 Towed 0 Galveston 1 2 8 RO Storage Barge NA 249 Towed 0 Houma 1 2 3 RO Storage Barge NA 249 Towed 0 Lake Charles 1 2 5.5 RO Storage Barge NA 249 Towed 0 Venice 1 2 0 
Shoreline Protection 

Staging Area: Venice 

Shoreline Protection 

Boom VOO Persons Req. Storage/Warehouse Location Hrs to Procure Hrs to Loadout Travel to Staging Travel to Deployment 

AMPOL (available through MSA) 

42,000’ 18” Boom 16 Crew 40 New Iberia, LA 2 2 4 2 20,000’ 18” Boom 8 Crew 20 New Orleans, LA 2 2 2 2 

Oil Mop (available through MSA) 

10,000’ 18” Boom 4 Crew 10 New Iberia, LA 1 1 4 2 10,000’ 18” Boom 4 Crew 10 Houston, TX 1 1 7.5 2 

10,000 18” Boom 4 Crew 10 Port Arthur, TX 1 1 6.25 2 20,000 18” Boom 8 Crew 20 Belle Chasse, LA 1 1 1.75 2 10,000 18” Boom 4 Crew 10 Port Allen, LA 1 1 3.5 2 10,000 18” Boom 4 Crew 10 Houma, LA 1 1 3.5 2 15,000 18” Boom 6 Crew 14 Gretna, LA 2 2 2 2 

Beach Boom EDRC Storage Capacity VOO Persons Req. From Hrs to Procure Hrs to Loadout Travel to Staging T

De

CGA 

Beach Boom (2000’) NA NA NA 6 Galveston 1 2 8 Beach Boom (1000’) NA NA NA 4 Ingleside 1 2 11 Beach Boom (2000’) NA NA NA 6 Pascagoula 1 2 4 
Wildlife Response EDRC Storage Capacity VOO Persons Req. From Hrs to Procure Hrs to Loadout Travel to Staging T

De

CGA 

Wildlife Support Trailer NA NA NA 2 Houma 1 2 3 Bird Scare Guns (24) NA NA NA 2 Belle Chasse 1 2 2 Bird Scare Guns (12) NA NA NA 2 Galveston 1 2 8 Bird Scare Guns (24) NA NA NA 2 Houma 1 2 3 Bird Scare Guns (12) NA NA NA 2 Ingleside 1 2 11 Bird Scare Guns (24) NA NA NA 2 Lake Charles 1 2 5.5 Bird Scare Guns (24) NA NA NA 2 Pascagoula 1 2 4 

Response Asset Total 

Offshore EDRC 318,609 Offshore Recovered Oil Storage 389,870 Nearshore / Shallow Water EDRC 54,753 Nearshore / Shallow Water Recovered Oil Storage 88,709 
Mississippi Canyon Block 253 (OCS-G 24062) 6/16/2011 

Mississippi Canyon Block 208 (OCS-G-32303) 

Revised Exploration Plan 15

 

APPENDIX I 

ENVIRONMENTAL MONITORING INFORMATION

(30 CFR PART 250.221 AND 250.252) 

A. Monitoring Systems

LLOG subscribes to Impact Weather Service which provides access to realtime weather conditions, and provides periodic updates on impending 

inclement weather conditions such as tropical depressions, storms and/or 

hurricanes entering the Gulf of Mexico. 

LLOG also relies on the National Weather Service to support the 

aforementioned subscribed service. During impending inclement weather 

conditions, LLOG closely coordinates the activity with our contractors and 

field personnel to ensure the safety of people for evacuation; measures to 

prepare the facility for evacuation to ensure protection of the environment and 

the facility/equipment. 

Mississippi Canyon Blocks 253 and 208 are in water depths greater than 400 

meters (1,312’); therefore LLOG will follow the guidelines of the applicable 

NTL 2009-G02 by monitoring and gathering ocdan current data using 

Acoustic Doppler Current Profile (ADCP) while the MODU is on location. 

No change – Refer to Initial EP for MC 253, OCS-G-24062 Lease and MC 

208, OCS-G-32303, Control No. N-09406 approved on October 22, 2009. 

B. Incidental Takes

LLOG does not anticipate the incidental taking of any species as a result of 

the proposed activities based on the implementation of, and adherence to, the 

NTL 2007-G03 “Marine Trash and Debris Awareness Training and 

Elimination” and NTL 2007-G04 “Vessel Strike Avoidance and Injured/Dead 

Protected Species Reporting”. 

No change – Refer to Initial EP for MC 253, OCS-G-24062 Lease and MC 

208, OCS-G-32303, Control No. N-09406 approved on October 22, 2009. 

C. Flower Garden Banks National Marine Sanctuary

This section of the plan is not applicable to the proposed operations. 

No change – Refer to Initial EP for MC 253, OCS-G-24062 Lease and MC 

208, OCS-G-32303, Control No. N-09406 approved on October 22, 2009. 
Mississippi Canyon Block 253 (OCS-G 24062) 6/16/2011 

Mississippi Canyon Block 208 (OCS-G-32303) 

Revised Exploration Plan 16

 

APPENDIX J 

LEASE STIPULATIONS/SPECIAL CONDITIONS INFORMATION

(30 CFR PART 250.222 AND 250.253) 

A. Lease Stipulations

Minerals Management Service (BOEMRE) did not invoke any stipulations for 

Leases OCS-G-24062 and OCS-G-32303, Mississippi Canyon Blocks 253 and 

208, respectively, 

No change – Refer to Initial EP for MC 253, OCS-G-24062 Lease and MC 

208, OCS-G-32303, Control No. N-09406 approved on October 22, 2009. 

B. Special Conditions

• Subsea Completions

LLOG may potentially complete the proposed wells as subsea 

completions. Therefore, LLOG will follow the regulations in Title 30 

CFR Parts 250.288 through 250.290, which mandates the submittal and 

approval of separate regulatory filings entitled a “Conservation 

Information Document” and a “Deepwater Operations Plan”, respectively. 

 

• Breton Sound Area

Mississippi Canyon Blocks 208 and 253 are located within the 200 km 

zone of the Breton National Wildlife Refuge, and will consider the use of 

best available control technology as required as Notice to Lessees 98-10 if 

the projected air emissions are determined to significantly affect the air 

quality of an onshore area. 

• Ocean Current Monitoring

The proposed operations under this Plan are in water depths greater than 

400 meters (1,312’); therefore, LLOG will follow the guidelines of the 

applicable NTL 2009-G02 by continuously monitoring and gathering 

ocean current data using Acoustic Doppler Current Profile (ADCP) while 

the MODU is on location. 

No change – Refer to Initial EP for MC 253, OCS-G-24062 Lease and 

MC 208, OCS-G-32303, Control No. N-09406 approved on October 

22, 2009. 
Mississippi Canyon Block 253 (OCS-G 24062) 6/16/2011 

Mississippi Canyon Block 208 (OCS-G-32303) 

Revised Exploration Plan 17

 

APPENDIX K 

ENVIRONMENTAL MITIGATION MEASURES INFORMATION

(30 CFR Part 250.23 and 250.54) 

A. Measures Taken to Avoid, Minimize, and Mitigate Impacts

This section does not apply to the operations as proposed herein. 

B. Incidental Takes

LLOG does not anticipate the incidental taking of any species as a result of the 

proposed activities based on the implementation of, and adherence to, the NTL 

2007-G03 “Marine Trash and Debris Awareness Training and Elimination” and 

NTL 2007-G04 “Vessel Strike Avoidance and Injured/Dead Protected Species 

Reporting”. 

No change – Refer to Initial EP for MC 253, OCS-G-24062 Lease and MC 

208, OCS-G-32303, Control No. N-09406 approved on October 22, 2009.
Mississippi Canyon Block 253 (OCS-G 24062) 6/16/2011 

Mississippi Canyon Block 208 (OCS-G-32303) 

Revised Exploration Plan 18

 

APPENDIX L 

 RELATED FACILITIES AND OPERATIONS INFORMATION

(30 CFR PART 250.256) 

A. Produced Liquid Hydrocarbon Transportation Vessels

Not applicable to proposed operations. 

No change – Refer to Initial EP for MC 253, OCS-G-24062 Lease and MC 

208, OCS-G-32303, Control No. N-09406 approved on October 22, 2009.
Mississippi Canyon Block 253 (OCS-G 24062) 9/13/2011 

Mississippi Canyon Block 208 (OCS-G-32303) 

Revised Exploration Plan 19

 

APPENDIX M 

SUPPORT VESSELS AND AIRCRAFT INFORMATION

(30 CFR PART 250.224 AND 250.257) 

A. General

Personnel involved in the proposed operations will typically use their own 

vehicles as transportation to and from the selected onshore base; whereas the 

selected vendors will transport the equipment by a combination of trucks, boats 

and/or helicopters to the onshore base. The personnel and equipment will then be 

transported to the drilling rig via the transportation methods and frequencies 

shown, taking the most direct route feasible as mandated by weather and traffic 

conditions: 

Type Maximum Fuel 

Tank Storage 

Capacity 

Maximum No. in 

Area at Any Time 

Trip Frequency or 

Duration 

Tug Boats 3000 bbls 1 Every two weeks 

Supply Boats 500 bbls 1 Three times weekly 

Service Boats 500 bbls 1 Daily 

Crew Boats 500 bbls 1 Weekly 

Aircraft 1900 lbs 1 As Needed 

No change – Refer to Initial EP for MC 253, OCS-G-24062 Lease and MC 

208, OCS-G-32303, Control No. N-09406 approved on October 22, 2009.

B. Diesel Oil Supply Vessels

Size of Fuel Supply 

Vessel 

Capacity of fuel 

Supply Vessel 

Frequency of Fuel 

Transfers 

Route Fuel Supply 

Vessel Will Take 

180’ 1,500 bbls Weekly From shorebase in 

Fourchon, LA to MC 

208/253 

C. Drilling Fluids Transportation

See Table 2 – Wastes you will Transport and/or Dispose of Onshore, located in 

Appendix F of this Plan. 

D. Solid and Liquid Wastes Transportation

See Table 2 – Wastes you will Transport and/or Dispose of Onshore, located in 

Appendix F of this Plan. 
Mississippi Canyon Block 253 (OCS-G 24062) 7/7/2011 

Mississippi Canyon Block 208 (OCS-G-32303) 

Revised Exploration Plan 20

 

E. Vicinity Map

A Vicinity Plat showing the location of Mississippi Canyon Blocks 208 and 253 

relative to the nearest shoreline and onshore base is included as Attachment K. 


Mississippi Canyon Block 253 (OCS-G 24062) 6/16/2011 

Mississippi Canyon Block 208 (OCS-G-32303) 

Revised Exploration Plan 21

 

APPENDIX N

ONSHORE SUPPORT FACILITIES INFORMATION

(30 CFR PART 250.225 AND 250.258) 

 A. General

The proposed surface disturbances in Mississippi Canyon Blocks 253 and 208 

will be located approximately 54 miles from the nearest Louisiana shoreline, 

and approximately 116 miles from the following onshore support base: 

Name Location Existing/New/Modified

Martin North Fourchon, LA Existing 

LLOG will use an existing onshore base to accomplish the following routine 

operations: 

● Loading/Offloading point for equipment supporting the offshore 

operations. 

● Dispatching personnel and equipment, and does not anticipate the need for 

any expansion of the selected facilities as a result of the activities 

proposed in this Revised Plan. 

● Temporary storage for materials and equipment. 

● 24 Hour Dispatcher 

B. Support Base Construction or Expansion

The proposed operations are temporary in nature and do not require any 

immediate action to acquire additional land or expand existing base facilities. No 

change – Refer to Initial EP for MC 253, OCS-G-24062 Lease and MC 208, 

OCS-G-32303, Control No. N-09406 approved on October 22, 2009. 

C. Support Base Construction or Expansion Timetable

This section of the plan is not applicable to the proposed operations. No change – 

Refer to Initial EP for MC 253, OCS-G-24062 Lease and MC 208, OCS-G32303, Control No. N-09406 approved on October 22, 2009. 

 

D. Waste Disposal

See Table 2 – Wastes you will Transport and/or Dispose of Onshore, located in 

Appendix F of this Plan. 
Mississippi Canyon Block 253 (OCS-G 24062) 6/16/2011 

Mississippi Canyon Block 208 (OCS-G-32303) 

Revised Exploration Plan 22

 

APPENDIX O

 COASTAL ZONE MANAGEMENT ACT (CZMA) INFORMATION

(30 CFR PART 250.226 AND 250.260) 

A. Consistency Certification

. 

A certificate of Coastal Zone Management Consistency for the States of 

Louisiana, Mississippi and Alabama are enclosed as Attachment L. No 

change – Refer to Attachment L of the Initial EP for MC 253, OCS-G24062 Lease and MC 208, OCS-G-32303, Control No. N-09406 approved 

on October 22, 2009.

B. Other Information

Included as Attachment M are the enforceable policies from the States of 

Mississippi and Alabama that are related to OCS Plan Filings. 

LLOG has considered all of Louisiana’s enforceable policies and certifies the 

consistency for the proposed operations. 

No change – Refer to Attachment M of the Initial EP for MC 253, OCS-G24062 Lease and MC 208, OCS-G-32303, Control No. N-09406 approved 

on October 22, 2009.


















Mississippi Canyon Block 253 (OCS-G 24062) 6/16/2011 

Mississippi Canyon Block 208 (OCS-G-32303) 

Revised Exploration Plan 23

 

APPENDIX P 

ENVIRONMENTAL IMPACT ANALYSIS

(30 CFR PART 250.227 AND 250.261) 

A. Impact Producing Factors (IPF’s) From Proposed Activities

The following matrix is utilized to identify the affected environments that 

could be impacted by these IPF’s. An “x” has been marked for each IPF 

category that Tana has determined may impact a particular environment as a 

result of the proposed activities. For those cells which are footnoted, a 

statement is provided as to the applicability of the proposed activities, and 

where there may be an effect, an analysis of the effect is provided. 

Environmental Resources Impact Producing Factors (IPF’s) 

Emissions 

(air, noise, 

light, etc) 

Effluents 

(muds, cuttings, 

other discharges 

to the water 

column or 

seafloor) 

Physical 

disturbances 

to the seafloor 

(rig, anchor, 

structure 

emplacement, 

etc.) 

Wastes sent 

to shore for 

treatment 

or disposal 

Accidents 

(e.g., oil 

spills, 

chemical 

spills, H2S 

releases) 

Discarded 

Trash & 

Debris 

Site Specific at Offshore 

Location

 

Designated topographic 

features 

 (1) (1) (1) 

Pinnacle Trend area live 

bottoms 

 (2) (2) (2) 

Eastern Gulf live bottoms (3) (3) (3) 

Chemosynthetic communities (4) 

Water quality X X 

Fisheries X X X 

Marine mammals X (8) X X (8) 

Sea turtles X (8) X X (8) 

Air quality (9) 

Shipwreck sites (known or 

potential) 

 (7) 

Prehistoric archaeological sites (7) 

 

Vicinity of Offshore Location

Essential fish habitat X (6) 

Marine and pelagic birds X 

Public health and safety (5) 

 

Coastal and Onshore

Beaches (6) 

Wetlands (6) 

Shorebirds and coastal nesting 

birds 

 (6) 

Coastal wildlife refuge 

Wilderness areas 
Mississippi Canyon Block 253 (OCS-G 24062) 6/16/2011 

Mississippi Canyon Block 208 (OCS-G-32303) 

Revised Exploration Plan 24

 

Footnotes for Environmental Impact Analysis Matrix: 

1. Activities that may affect a marine sanctuary or topographic feature. Specifically, if the well or 

platform site or any anchors will be on the seafloor within the: 

(a) 4-mile zone of the Flower Gardens Banks, or the 3-mile zone of Stetson Bank; 

(b) 1000-m, 1-mile or 3-mile zone of any topographic feature (submarine bank) protected by 

the Topographic Features Stipulation attached to an OCS lease; 

(c) Essential Fish Habitat (EFH) criteria of 500 feet from any no-activity zone; or 

(d) Proximity of any submarine bank (500 ft buffer zone) with relief greater than 2 meters that 

is not protected by the Topographic Stipulation attached to an OCS lease. 

2. Activities with any bottom disturbance within an OCS lease block protected through the Live Bottom 

(Pinnacle Trend) Stipulation attached to an OCS lease. 

3. Activities within any Eastern Gulf OCS block where seafloor habitats are protected by the Live 

Bottom (Low-Relief) Stipulation attached to an OCS lease. 

4. Activities on blocks designated by the BOEMRE as being in water depths 300 meters or greater. 

5. Exploration or production activities where H2S concentrations greater than 500 ppm might be 

encountered. 

6. All activities that could result in an accidental spill of produced liquid hydrocarbons or diesel fuel that 

you determine would impact these environmental resources. If the proposed action is located a 

sufficient distance from a resource that no impact would occur, the EIA can note that in a sentence or 

two. 

7. All activities that involve seafloor disturbances, including anchor emplacements, in any OCS block 

designated by the BOEMRE as having high-probability for the occurrence of shipwrecks or prehistoric 

sites, including such blocks that will be affected that are adjacent to the lease block in which your 

planned activity will occur. If the proposed activities are located a sufficient distance from a 

shipwreck or prehistoric site that no impact would occur, the EIA can note that in a sentence or two. 

8. All activities that you determine might have an adverse effect on endangered or threatened marine 

mammals or sea turtles or their critical habitats. 

9. Production activities that involve transportation of produced fluids to shore using shuttle tankers or 

barges. 
Mississippi Canyon Block 253 (OCS-G 24062) 6/16/2011 

Mississippi Canyon Block 208 (OCS-G-32303) 

Revised Exploration Plan 25

 

B. Impact Analysis

LLOG does not anticipate any unforeseen incidents from the proposed 

activities which could significantly impact the associated environment. 

LLOG activities associated with this Exploration Plan (Plan) will be 

performed with prudent and industry accepted standards, and in compliance 

with the federal agency regulations and oversight. 

The “Oil Spills Information” Section of this Plan details the potential worse 

case discharge volume which has been calculated based on the new Bureau of 

Ocean Energy Management, Regulation and Enforcement (BOEMRE) Notice 

to Lessees (NTL 2010-N06). Response details associated with an 

unanticipated spill from this site are detailed in our Regional Oil Spill 

Response Plan (OSRP) which outlines the potential spill scenario, spill 

volumes, anticipated trajectory of the spill, response equipment available, and 

actions to be taken to respond to the potential spill incident. Additional 

measures implemented by LLOG is trajectory analyses to be obtained prior to 

and during the proposed activities, contractual arrangements with well control 

specialists and preliminary reviews of potential well intervention scenarios, 

and to supplement existing contracted response/clean-up equipment with 

equipment offered by Helix which specializes in subsea deepwater well 

intervention, containment and processing. 

 Site Specific at Offshore Location

• Designated Topographic Features

There are no anticipated emissions, effluents, physical disturbances to the 

seafloor, wastes transported to shore, and/or accidents from the proposed 

activities that could cause impacts to topographic features. 

The proposed surface disturbances within Mississippi Canyon Blocks 208 

& 253 are located approximately 72 miles away from the closest 

designated topographic feature (Sackett Bank). 

The crests of these designated topographic features in the northern Gulf 

are typically found below 10 m; therefore, concentrated oil from a surface 

spill is not likely to reach sessile biota. Subsurface spills could cause 

adverse impacts to a designated topographic feature; however, due to the 

offset distance this should not have an impact. 

In the event of an unanticipated spill, LLOG would immediately 

implement its Regional Oil Spill Response Plan and active source control 

and countermeasures to minimize these potential impacts. 

 
Mississippi Canyon Block 253 (OCS-G 24062) 6/16/2011 

Mississippi Canyon Block 208 (OCS-G-32303) 

Revised Exploration Plan 26

 

• Pinnacle Trend Area Live Bottoms

There are no anticipated emissions, effluents, physical disturbances to the 

seafloor, wastes sent to shore and/or accidents from the proposed activities 

that could cause impacts to a pinnacle trend area. 

The proposed surface disturbances within Mississippi Canyon Blocks 208 

& 253 are located a significant distance (> 100 miles) from the closest 

pinnacle trend live bottom stipulated block. The crests of these pinnacle 

trend areas are much deeper than 20 m. 

During the surface location disturbance review, LLOG reviews potential 

surface impacts, and would be able to identify any pinnacles within the 

vicinity and would avoid placement of any surface disturbances such as a 

drilling rig and associated anchors. These surface location disturbance 

areas would be avoided and/or mitigated during the review and approval 

process by the BOEM. 

In the event of an unanticipated spill, LLOG would immediately 

implement its Regional Oil Spill Response Plan and activate source 

control and countermeasures to minimize these potential impacts. 

• Eastern Gulf Live Bottoms

There are no anticipated emissions, effluents, emissions physical 

disturbances to the seafloor, wastes sent to shore, and/or accidents from 

the proposed activities that could cause impacts to Eastern Gulf live 

bottoms. 

The proposed surface disturbances within Mississippi Canyon Blocks 208 

& 253 are located a significant distance (> 100 miles) from the closest 

Eastern Gulf live bottoms stipulated block. During the surface location 

disturbance review, LLOG previews potential surface impacts, and would 

be able to identify any live bottom areas within the vicinity and would 

avoid placement of any surface disturbances such as a drilling rig and 

associated anchors. 

In the event of an unanticipated spill, LLOG would immediately 

implement its Regional Oil Spill Response Plan and activate source 

control and countermeasures to minimize these potential impacts. 

• Chemosynthetic Communities

Water depths at the surface locations in Mississippi Canyon Blocks 208 & 

253 range from 4,100 feet to 5,200 feet including anchor radius. As noted 
Mississippi Canyon Block 253 (OCS-G 24062) 6/16/2011 

Mississippi Canyon Block 208 (OCS-G-32303) 

Revised Exploration Plan 27

 

in the shallow hazards assessment (Attachment I in the Initial Exploration 

Plan) it is unlikely that the identified anomalies represent the presence of 

high-density chemosynthetic or other benthic communities. 

• Water Quality

Bottom disturbances which may result based on placement of drilling rigs 

during an exploratory phase could increase water column turbidity and 

redistribution of any accumulated pollutants in the water column; which 

could cause temporary impacts on water quality conditions in the 

immediate vicinity. 

Associated overboard effluents are regulated by the EPA Region VI 

NPDES General Permit GMG290000 which mandates volume discharge 

rate limitations, certain testing requirements for toxicity and oil and grease 

limitations. As such, it is not anticipated these discharges authorized 

under the approved EPA NPDES permit will cause significant adverse 

impacts to water quality. 

Certain wastes generated from the proposed activities will be manifested 

and sent to shore for treatment and/or disposal at approved facilities. 

Other waste which may be considered hazardous will be collected and 

transported in sealed containers and transported to approve disposal sites 

in accordance with the RCRA regulations and guidelines. 

An accidental oil spill release from the proposed activities, and cumulative 

similar discharge activity within the vicinity could potentially cause 

temporary impacts to water quality. In the event of such a release, the 

water quality would be temporarily affected by the dissolved components 

and small droplets. Currents and microbial degradation would remove the 

oil from the water column or dilute the constituents to background levels. 

In the event of an unanticipated blowout, LLOG will implement industry 

wide standards for using proven equipment and technology for such 

responses. LLOG would immediately implement its Regional Oil Spill 

Response Plan and activate source control and countermeasures to 

minimize these potential impacts. 

• Fisheries

Accidental oil spill releases from the proposed activities, and cumulative 

similar discharge activity within the vicinity may potentially cause some 

detrimental effects on fisheries. It is unlikely a spill would occur; 

however, such a release in open waters closed to mobile adult finfish or 

shellfish would likely be sub-lethal and the extent of damage would be 

reduced to the capability of adult fish and shellfish to avoid a spill, to 
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Mississippi Canyon Block 208 (OCS-G-32303) 

Revised Exploration Plan 28

 

metabolize hydrocarbons, and to excrete both metabolites and parent 

compounds. 

In the event of an unanticipated blowout, LLOG will implement industry 

wide standards for using proven equipment and technology for such 

responses. LLOG would immediately implement its Regional Oil Spill 

Response Plan and activate source control and countermeasures to 

minimize these potential impacts. 

• Marine Mammals

GulfCet II studies reveal that cetaceans of the continental shelf and shelf 

edge are comprised of bottlenose dolphin and Atlantic spotted dolphin. 

Squid eaters, including dwarf and pygmy killer wale, Risso’s dolphin and 

Cuvier’s beaked whale occur most frequently along the upper slope in 

areas outside of anticyclones. 

As a result of the proposed activities, marine mammals may be adversely 

impacted by emissions, effluents, waste sent to shore and/or accidents. 

Chronic and sporadic sub-lethal effects would occur that may stress and/or 

weaken individuals of a local group or population and make them more 

susceptible to infection from natural or anthropogenic sources. Few lethal 

effects are expected from an accidental oil spill, chance collisions with 

service vessels and ingestion of plastic material. 

The net results of any disturbance would depend on the size and 

percentage of the population affected, ecological importance of the 

disturbed area, environmental and biological parameters that influence an 

animal’s sensitivity to disturbance and stress, and the accommodation time 

in response to prolonged disturbance (Geraci and St. Aubin, 1980). 

Collisions between cetaceans and ship could cause serious injury or death 

(Laist et al., 2001). 

Sperm whales are one of 11 whale species that are hit commonly by ships 

(Laist et al., 2001). Collisions between OCS vessels and cetaceans within 

the project area are expected to be unusual events. 

LLOG does not anticipate the incidental taking of any marine mammals as 

the result of the proposed activities. The proposed activities will be 

conducted by our company and its contractors under the additional criteria 

addressed by BOEMRE in Notice to Lessees (NTLs) 2007-G04 “Vessel 

Strike Avoidance and Injured/Dead Protective Species” and 2007-G03 

“Marine Trash & Debris Awareness & Elimination”. The proposed 

operations will be conducted in accordance with the regulations via 

manifesting waste sent to shore and ensuring such wastes are contained to 
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Revised Exploration Plan 29

 

prevent loss. Informational placards will be maintained on the facility, 

and LLOG and the associated contractors obtain training on at least an 

annual basis to ensure personnel are aware of the reporting and operational 

requirements. 

LLOG will conduct the proposed activities under EPA’s Region VI 

NPDES General Permit GMG290000 which authorizes the discharge of 

certain effluents, subject to certain limitations, prohibitions and 

recordkeeping requirements. As such, it is not anticipated these 

discharges authorized under the approved EPA NPDES permit will not 

cause significant adverse impacts to water quality. 

In the event of an unanticipated blowout, LLOG will implement industry 

wide standards for using proven equipment and technology for such 

responses. LLOG would immediately implement its Regional Oil Spill 

Response Plan and activate source control and countermeasures to 

minimize these potential impacts. 

• Sea Turtles

Small numbers of turtles could be killed or injured by chance collision 

with service vessels or by eating indigestible trash, particularly plastic 

items accidentally lost from drilling rigs, production facilities and service 

vessels. Drilling rigs and project vessels produce noise that could disrupt 

normal behavior patterns and create some stress to sea turtles, making 

them more susceptible to disease. Accidental oil spill releases are 

potential threats which could have lethal effects on turtles. Contact and/or 

consumption of this released material could seriously affect individual sea 

turtles. Most OCS related impacts on sea turtles are expected to be sublethal. Chronic and/or avoidance of affected areas could cause declines in 

survival or productivity, resulting in gradual population declines. 

LLOG will conduct the proposed activities under EPA’s Region VI 

NPDES General Permit GMG290000 which authorizes the discharge of 

certain effluents, subject to certain limitations, prohibitions and 

recordkeeping requirements. As such, it is not anticipated these 

discharges authorized under the approved EPA NPDES permit will not 

cause significant adverse impacts to water quality. 

Additionally, LLOG and its contractors will conduct the proposed 

activities under the additional criteria addressed by BOEMRE in Notice to 

Lessees (NTLs) 2007-G04 “Vessel Strike Avoidance and Injured/Dead 

Protective Species” and 2007-G03 “Marine Trash & Debris Awareness & 

Elimination”. The proposed operations will be conducted in accordance 

with the regulations via manifesting waste sent to shore and ensuring such 

wastes are contained to prevent loss. Informational placards will be 
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Mississippi Canyon Block 208 (OCS-G-32303) 

Revised Exploration Plan 30

 

maintained on the facility, and LLOG and the associated contractors 

obtain training on at least an annual basis to ensure personnel are aware of 

the reporting and operational requirements. 

In the event of an unanticipated blowout, LLOG will implement industry 

wide standards for using proven equipment and technology for such 

responses. LLOG would immediately implement its Regional Oil Spill 

Response Plan and activate source control and countermeasures to 

minimize these potential impacts. 

• Air Quality

The proposed activities are located approximately 48 miles to the nearest 

shoreline. LLOG has addressed the air quality issues associated with the 

proposed activities in the “Air Emissions Information” section of this Plan 

as a result of the proposed activities. 

• Ship Wreck Sites (Known or Potential)

There are no physical disturbances to the seafloor which could impact 

known or potential shipwreck sites, as the review of high resolution 

shallow hazards data indicate there are no known or potential shipwreck 

sites located within the survey area. As such, LLOG does not anticipate 

any IPF’s as a result of the proposed activities. 

• Prehistoric Archaeological Sites

There are no physical disturbances to the seafloor which could cause 

impacts to prehistoric archaeological sites, as the review of high resolution 

shallow hazards data and supporting studies did not reflect the occurrence 

of prehistoric archaeological sites. As such LLOG does not anticipate any 

IPF’s as a result of the proposed activities. 

Vicinity of Offshore Location

• Essential Fish Habitat

As a result of the proposed activities, essential fish habitat may be 

adversely impacted by effluents and/or accidents. 

An Accidental oil spill that may occur as a result of the proposed activities 

has potential to cause some detrimental effects on essential fish habitat. It 

is unlikely that an accidental oil spill release would occur; however, if a 

spill were to occur in close proximity to finfish or shellfish, the effects 
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Revised Exploration Plan 31

 

would likely be sub-lethal and the extent of damage would be reduced to 

the capability of adult fish and shellfish to avoid a spill, to metabolize 

hydrocarbons and to excrete both metabolites and parent compounds. 

In the event of an unanticipated blowout, LLOG will implement industry 

wide standards for using proven equipment and technology for such 

responses. LLOG would immediately implement its Regional Oil Spill 

Response Plan and activate source control and countermeasures to 

minimize these potential impacts. 

• Marine and Pelagic Birds

As a result of the proposed activities, marine and pelagic birds may be 

adversely impacted by an accidental oil spill, by the birds coming into 

contact with the released oil. 

In the event of an unanticipated blowout resulting in an oil spill, it is likely 

to have an impact based on the industry wide standards for using proven 

equipment and technology for such responses. In that event, LLOG will 

implement the Regional Oil Spill Response Plan and activate source 

control and countermeasures to minimize these potential impacts. 

• Public Health and Safety

There are no anticipated emissions, effluents, wastes sent to shore, and/or 

accidents from the proposed activities that could cause impacts to the 

public health safety. LLOG has requested BOEMRE approval to classify 

the proposed objective area as absent of hydrogen sulfide. 

Coastal and Onshore

• Beaches

As a result of the proposed activities, beaches may be adversely impacted 

by an accidental oil spill. However, due to the distance from shore 

(approximately 48 miles), and the response capabilities that would be 

implemented, no significant adverse impacts are expected. Both historical 

spill data and the combined trajectory/risk calculations referenced in the 

publication of OCS EIA/EA BOEMRE 2002-052 indicate there is little 

risk of contact or impact to the coastline and associated environmental 

resources. 

In the event of an unanticipated blowout, LLOG will implement industry 

wide standards for using proven equipment and technology for such 
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Revised Exploration Plan 32

 

responses. LLOG would immediately implement its Regional Oil Spill 

Response Plan and activate source control and countermeasures to 

minimize these potential impacts. 

• Wetlands

As a result of the proposed activities, wetlands may be adversely impacted 

by an accidental oil spill. However, due to the distance from shore 

(approximately 54 miles) and the response capabilities that would be 

implemented, no significant adverse impacts are expected. Both historical 

spill data and the combined trajectory/risk calculations referenced in the 

publication of OCS EIA/EA BOEMRE 2002-052 indicate there is little 

risk of contact or impact to the coastline and associated environmental 

resources. 

In the event of an unanticipated blowout, LLOG will implement industry 

wide standards for using proven equipment and technology for such 

responses. LLOG would immediately implement its Regional Oil Spill 

Response Plan and activate source control and countermeasures to 

minimize these potential impacts. 

• Shore Birds and Coastal Nesting Birds

As a result of the proposed activities, shore birds and coastal nesting birds 

may be adversely impacted by an accidental oil spill. However, due to the 

distance from shore (approximately 54 miles) and the response capabilities 

that would be implemented, no significant adverse impacts are expected. 

Both historical spill data and the combined trajectory/risk calculations 

referenced in the publication of OCS EIA/EA BOEMRE 2002-052 

indicate there is little risk of contact or impact to the coastline and 

associated environmental resources. 

In the event of an unanticipated blowout, LLOG will implement industry 

wide standards for using proven equipment and technology for such 

responses. LLOG would immediately implement its Regional Oil Spill 

Response Plan and activate source control and countermeasures to 

minimize these potential impacts. 

• Coastal Wildlife Refuges

As a result of the proposed activities, coastal wildlife refuges may be 

adversely impacted by an accidental oil spill. However, due to the 

distance from shore (approximately 54 miles) and the response capabilities 

that would be implemented, no significant adverse impacts are expected. 

Both historical spill data and the combined trajectory/risk calculations 

referenced in the publication of OCS EIA/EA BOEMRE 2002-052 
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Mississippi Canyon Block 208 (OCS-G-32303) 

Revised Exploration Plan 33

 

indicate there is little risk of contact or impact to the coastline and 

associated environmental resources. 

In the event of an unanticipated blowout, LLOG will implement industry 

wide standards for using proven equipment and technology for such 

responses. LLOG would immediately implement its Regional Oil Spill 

Response Plan and activate source control and countermeasures to 

minimize these potential impacts. 

• Wilderness Area

As a result of the proposed activities, wilderness areas may be adversely 

impacted by an accidental oil spill. However, due to the distance from 

shore (approximately 54 miles) and the response capabilities that would be 

implemented, no significant adverse impacts are expected. Both historical 

spill data and the combined trajectory/risk calculations referenced in the 

publication of OCS EIA/EA BOEMRE 2002-052 indicate there is little 

risk of contact or impact to the coastline and associated environmental 

resources. 

In the event of an unanticipated blowout, LLOG will implement industry 

wide standards for using proven equipment and technology for such 

responses. LLOG would immediately implement its Regional Oil Spill 

Response Plan and activate source control and countermeasures to 

minimize these potential impacts. 

Other Resources Identified

LLOG has not identified any other environmental resources other than those 

addressed above. 

C. Impacts of Proposed Activities

LLOG does not anticipate any impacts on the offshore site specific locations, 

offshore vicinity, and/or coastal and onshore environmental conditions based 

on the potential impacts identified in the EIA worksheets and historical 

operations in the exploration of this reservoir. 

D. Environmental Hazards

The Gulf of Mexico may experience several hurricanes throughout the season 

which typically runs from June through November. A severe hurricane may 

impact the activities covered in this Plan. Such impacts may be damage to the 

drilling rig, the unanticipated release of hydrocarbons depending upon the 
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Revised Exploration Plan 34

 

current status of the well. Additionally, the surface located in Mississippi 

Canyon Blocks 208 & 253 has the potential to be affected by the “Loop 

Current” which is a warm ocean current in the Gulf of Mexico that flows 

northward between Cuba and the Yucatan Peninsula, moves northward into 

the Gulf of Mexico, then loops east and south before exiting to the east 

through the Florida Straits. While the loop current is present approximately 

95% of the time, it is most active in the summer and fall seasons. 

To mitigate potential impacts to the well during impending hurricanes or loop 

currents, LLOG will take precautionary measures by securing the well, rig and 

evacuation of personnel; and will comply with the requirements of NTL’s 

2008-G09 and 2009-G10. 

E. Alternatives

LLOG did not consider any alternatives to reduce environmental impacts as a 

result of the proposed activities. 

F. Mitigation Measures

LLOG will not implement any mitigation measures to avoid, diminish or 

eliminate potential environmental resources, other than those required by 

regulation and policy. 

G. Consultation

LLOG has not contacted any agencies or persons for consultation regarding 

potential impacts associated with the proposed activities. Therefore, a list of 

such entities is not being provided. 

H. Preparers

Questions or requests for additional information should be made to LLOG’s 

authorized representative of this Plan: 

Carol Eaton Kathy Gowland 

Regulatory Administrator Regulatory Specialist 

1001 Ochsner Boulevard, Suite 2000 1001 Ochsner Boulevard, Ste 2000 

Covington, Louisiana 70433 Covington, Louisiana 70433 

985-801-4300 (Phone) 985-801-4300 (Phone) 

Carole@llog.com Kathygo@llog.com 
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Revised Exploration Plan 35

 

I. References

The following documents were utilized in preparing the Environmental 

Impact Assessment: 

Document Author Dated 

Shallow Hazards Survey 

3-D GeoHazard Assessment 

C&C Technologies 

Gardline Surveys, Inc. 

2009 

2009 

BOEMRE Environmental Impact Statement Report No. 

2007-003 

Bureau of Ocean Energy Management, 

Regulation, and Enforcement 

2007 

Title 30 CFR Part 250 Subpart B (250.216 / 250.221 / 

250.223 / 250.227 

Bureau of Ocean Energy Management, 

Regulation, and Enforcement 

2006 

NTL 2000-G16 “Guidelines for General Lease Surety 

Bonds” 

Bureau of Ocean Energy Management, 

Regulation, and Enforcement 

2000 

NTL 2005-G07 “Archaeological Resource Surveys and 

Reports” 

Bureau of Ocean Energy Management, 

Regulation, and Enforcement 

2005 

NTL 2006-N06 “Flaring and Venting Regulations” Bureau of Ocean Energy Management, 

Regulation, and Enforcement 

2006 

NTL 2006-G07 “Revisions to the List of OCS Lease Blocks 

Requiring Archaeological Surveys and Reports:” 

Bureau of Ocean Energy Management, 

Regulation, and Enforcement 

2006 

NTL 2007-G02 “Implementation of seismic Survey 

Mitigation Measures and Protected Species Observer 

Program” 

Bureau of Ocean Energy Management, 

Regulation, and Enforcement 

2007 

NTL 2007-G03 “Marine Trash & Debris Awareness & 

Elimination” 

Bureau of Ocean Energy Management, 

Regulation, and Enforcement 

2007 

NTL 2007-G04 “Vessel Strike Avoidance and Injured/Dead 

Protective Species” 

Bureau of Ocean Energy Management, 

Regulation, and Enforcement 

2007 

NTL 2008-G04 “Information Requirements for Exploration 

Plans and Development Operations Coordination 

Documents” 

Bureau of Ocean Energy Management, 

Regulation, and Enforcement 

2008 

NTL 2008-N05 “Guidelines for Oil Spill Financial 

Responsibility for Covered Offshore Facilities” 

Bureau of Ocean Energy Management, 

Regulation, and Enforcement 

2008 

NTL 2008-G06 “Remotely Operated Vehicle Surveys in 

Deepwater” 

Bureau of Ocean Energy Management, 

Regulation, and Enforcement 

2008 

NTL 2008-N07 “Supplemental Bond Procedures Bureau of Ocean Energy Management, 

Regulation, and Enforcement 

2008 

NTL 2008-G20 “Revisions to the List of OCS Lease Blocks 

Requiring Archaeological Resource Surveys and Reports” 

Bureau of Ocean Energy Management, 

Regulation, and Enforcement 

2008 

NTL 2009-G02 “Ocean Current Monitoring” Bureau of Ocean Energy Management, 

Regulation, and Enforcement 

2009 

NTL 2009-G27 “Submitting Exploration Plans and 

Development Operations Coordination Documents” 

Bureau of Ocean Energy Management, 

Regulation, and Enforcement 

2009 

NTL 2009-G29 “Implementation Plan for Transition from 

North American Datum 27 to North American Datum 83” 

Bureau of Ocean Energy Management, 

Regulation, and Enforcement 

2009 

NTL 2009-G31 “Hydrogen Sulphide” Bureau of Ocean Energy Management, 

Regulation, and Enforcement 

2009 

NTL 2009-G34 “Ancillary Activities” Bureau of Ocean Energy Management, 

Regulation, and Enforcement 

2009 

NTL 2009-G38 “Drilling Windows, Eastern Gulf of 

Mexico” 

Bureau of Ocean Energy Management, 

Regulation, and Enforcement 

2009 

NTL 2009-G39 “Biologically-Sensitive Underwater 

Features and Areas” 

Bureau of Ocean Energy Management, 

Regulation, and Enforcement 

2009 

NTL 2009-G40 “Deepwater Benthic Communities” Bureau of Ocean Energy Management, 

Regulation, and Enforcement 

2009 

NTL 2009-N11 “Air Quality Jurisdiction on the OCS” Bureau of Ocean Energy Management, 

Regulation, and Enforcement 

2009 

NTL 2010-N05 “Increased Safety Measures for Energy 

Development on the OCS” 

Bureau of Ocean Energy Management, 

Regulation, and Enforcement 

2010 

NTL 2010-N06 “Information Requirements for EP’s, 

DOCD’s, DPP on the OCS” 

Bureau of Ocean Energy Management, 

Regulation, and Enforcement 

2010 

NPDES General Permit GMG290000 EPA – Region VI 2007 

Regional Oil Spill Response Plan LLOG Exploration Offshore, L.L.C. 2010 
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Mississippi Canyon Block 208 (OCS-G-32303) 

Revised Exploration Plan 36

 

APPENDIX Q 

ADMINISTRATIVE INFORMATION

(30 CFR Part 250.228 and 250.262) 

A. Exempted Information Description (Public Information Copies 

only

Excluded from the Public Information copies are the following: 

• Proposed bottomhole location information 

• Proposed total well depths (measured and true vertical depth) 

• Production Rates and Life of Reserves 

• New and Unusual Technologies 

• Geological and Geophysical Attachments 

B. Bibliography

The following documents were utilized in preparing this Plan: 

Document Author Dated 

Shallow Hazards Survey 

3-D GeoHazard Assessment 

C&C Technologies 

Gardline Surveys, Inc. 

2009 

2009 

BOEMRE Environmental Impact Statement Report – No. 

2007-003 

Bureau of Ocean Energy Management, 

Regulation, and Enforcement 

2007 

Regional Oil Spill Response Plan LLOG Exploration Offshore, L.L.C. 2010