UNITED STATES GOVERNMENT MEMORANDUM

To: Public Information (MS 5030)

Plans Section, Office of Field 

Operations (MS 5231)

Public Information copy of Exploration Plan

Control # - S-07550

Type - Supplemental Exploration Plan

Lease(s) - OCS-G10350 Block - 386 Garden Banks Area

Operator - Hess Corporation

Subsea Wells LL 4, LL5, LL5ST, and LL6

DP 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.

Karen Dunlap

Plan Coordinator

Description -

Rig Type -

Subject:

From:

May 31, 2012
FOR PUBLIC RELEASE
S‐7550

Record of Revisions

Date Rec’d Section, page number  

*Page number coincides with public version of the plan Revision  

03/23/2012 Description & Objectives ‐ Page 5 Remove DOCD references

03/23/2012 Well Information Form – Page 14 Revise LL6 BHL due to typographical error

03/23/2012 Applications & Permits – Page 23   Change MWA from 92 to 147AB and 59A

03/23/2012 Blowout Scenario – Page 25 Include calculation for maximum duration of the

potential blowout

03/23/2012 Shallow Hazards Report – Page 33 Revise wording; shallow hazards assessments were

submitted in 2009

03/23/2012 AQR – Pages 73‐78 Reference LL5ST, recalculate emissions based on

130 miles to shore   

03/23/2012 Oil Spill Response Plan – Pages 79‐80 Update OSRP modification submittal date

03/23/2012 Lease Stipulations ‐  Page 107 Include archaeological stipulation reference

05/02/2012 NA Shell Gulf of Mexico, Inc. files letter of no objection

for the activities proposed under Hess’ EP S‐7550

05/16/2012 Oil Spill Information – Pages 79‐80 Inclusion of OSRP approval date and certification

statement

05/16/2012 Oil Spill Information – Page 80 Revise WCD comparison table to include new WCD

volume included in the approved OSRP

05/16/2012 Support Vessel and Aircraft Information – Page

111 Revise fuel tank capacities of aircraft

05/16/2012 EP Submittal Letter – Page 1 Company contact information

FOR PUBLIC RELEASE
Hess Corporation    Llano Field  

Supplemental EP    Garden Banks Block 386, OCS‐G10350

Hess Corporation (00059)

Hess Tower, 1501 McKinney Street

Houston, TX 77010

SUPPLEMENTAL EXPLORATION PLAN

S‐7550

Llano Field

Unit Agreement #754391006

Garden Banks Block 386

OCS‐G10350

May 16, 2012

FOR PUBLIC RELEASE
Hess Corporation    Llano Field  

Supplemental EP    Garden Banks Block 386, OCS‐G10350

Hess Corporation

Supplemental EP

Llano Field

Garden Banks Block 386, OCS‐G10350

Unit Agreement No. 754391006

Table of Contents Appendix

Plan Contents................................................................................................................................................A

General Information.....................................................................................................................................B

Geological & Geophysical Information......................................................................................................C

Hydrogen Sulfide Information.....................................................................................................................D

Mineral Resource Conservation Information ...........................................................................................E

Biological, Physical & Socioeconomic Information...................................................................................F

Waste and Discharge Information.............................................................................................................G

Air Emissions Information...................................................................................................... .....................H

Oil Spills Information.....................................................................................................................................I

Environmental Monitoring Information.....................................................................................................J

Lease Stipulations Information...................................................................................................................K

Environmental Mitigation Measures Information....................................................................................L

Decommissioning Information..................................................................................................................M

Related Facilities and Operations Information.........................................................................................N

Support Vessels and Aircraft Information.................................................................................................O

Onshore Support Facilities Information.....................................................................................................P

Sulphur Operations Information................................................................................................................Q

Coastal Zone Management Act Information.............................................................................................R

Environmental Impact Analysis (EIA) .........................................................................................................S

Administrative Information.........................................................................................................................T

FOR PUBLIC RELEASE
Hess Corporation    Llano Field  

Supplemental EP    Garden Banks Block 386, OCS‐G10350

Appendix A

Plan Contents

(a) Description and Objectives

Lease OCS‐G10350 was awarded to Exxon Mobil at Gulf of Mexico Oil and Gas Lease Sale

Number 115 and became effective October 1, 1988.  The Garden Banks 388 Unit No. 754391006

was established in 1991.  Current Lease ownership is as follows:

In 2000, Newfield drilled the Garden Banks 386 Well No. 3 (with a surface location in Garden

Banks 385).  The Garden Banks 386 Well No. 3 was then completed as the Garden Banks 386 LL1

by Shell Gulf of Mexico, Inc. (SGOMI).  Under this S‐EP, Hess Corporation seeks approval to drill,

log, complete and secure the Garden Banks 386 wells:  LL4, LL5, LL5 ST (as basis of WCD) and

LL6.  Please see attachments A‐1 for a tentative schedule of the proposed operations.  Hess will

use the Atwood Condor, a dynamically‐positioned semi‐submersible rig to perform activities

proposed under this plan.  

No development or production activities are proposed under this Hess Corporation

Supplemental Exploration Plan.            

(b) Plan Information Form

Included under Appendix A are the following attachments:

Attachment A‐1: OCS Plan Information Forms BOEM‐0137  

Attachment A‐2: Well location plats

Attachment A‐3: Bathymetry maps  

Attachment A‐4: Pay.gov cost recovery fee receipt

  

(c) Location

Green Canyon Block 386 is located approximately 130 miles from nearest land.   The activities

proposed under this plan will be conducted using the Atwood Condor, a semi‐submersible,

dynamically‐positioned MODU.    Hess will not be using any moored vessels to carry out the

proposed activities.

Owner GWI

Hess Corporation 50%

Mobil Producing Texas & New Mexico Inc. 20%

Shell Gulf of Mexico Inc. 30%

FOR PUBLIC RELEASE
Hess Corporation    Llano Field  

Supplemental EP    Garden Banks Block 386, OCS‐G10350

(d) Safety and Pollution Prevention Features

Hess ensures that written operating procedures are available and implemented that provide

instructions for conducting safe and environmentally sound activities.   Safety features on the

Atwood Condor will include well control, pollution prevention, welding procedure, and blowout

prevention equipment as described in Title 30 CFR Part 250 and as further clarified by

BOEM/BSEE Notices to Lessees and current policy‐making invoked by BOEM/BSEE. BSEE is

required to conduct onsite inspections of offshore facilities to confirm that operators are

complying with lease stipulations, operating regulations, approved plans and other conditions,

as well as to assure that safety and pollution prevention requirements are being met. The

National Potential Incident of Noncompliance (PINC) List serves as the baseline for these

inspections. BSEE also inspects the stockpiles of equipment listed in the operator’s approved

Regional Oil Spill Response Plan that would be used for the containment and cleanup of

hydrocarbon spills.  Appropriate life rafts, life jackets, rig buoys, etc. will be maintained on the

facility at all times as mandated by the U.S. Coast Guard regulations contained in Title 33 CFR.  

The drilling rig and each of the marine vessels providing services for the exploration operations

will be equipped with all U.S. Coast Guard required navigational safety aids to alert ships of its

presence in all weather conditions.  Supervisory and certain designated personnel on‐board the

facility will be familiar with the effluent limitations and guidelines for overboard discharge into

the receiving waters, as outlined in the NPDES General Permit GMG290003.  No part of Garden

Banks 386 is located in a designated shipping fairway/anchorage area; therefore no permit from

the Department of Army Corps of Engineers New Orleans District will be required.

FOR PUBLIC RELEASE
Hess Corporation    Llano Field  

Supplemental EP    Garden Banks Block 386, OCS‐G10350

(e) Storage Tanks and Vessels

Type of

Storage Tank Type of Facility

Tank

Capacity

(bbls)

Number

of

Tanks

Total

Capacity

(bbls)

Fluid Gravity (API)

Fuel Oil

(Marine

Diesel)

DP Semi‐submersible:  

Atwood Condor 4,418 4 17,672 33.0°

Fuel Oil

(Marine

Diesel)

DP Semi‐submersible:  

Atwood Condor 3,787 1 3,787 33.0°

Fuel Oil

(Marine

Diesel)

DP Semi‐submersible:  

Atwood Condor 234 6 1,404 33.0°

Lube Oil DP Semi‐submersible:  

Atwood Condor 28 4 112 22.3°

Lube Oil DP Semi‐submersible:  

Atwood Condor 41 2 82 22.3°

Waste Oil DP Semi‐submersible:  

Atwood Condor 325 1 325 6.5°

Waste Oil DP Semi‐submersible:  

Atwood Condor 49 1 49 6.5°

(f) Pollution Prevention and Additional Measures

Hess Corporation is committed to excellence in environmental, health and safety performance.  

Hess Management will continue to support the American Petroleum Institute (API), the Offshore

Operators’ Committee (OOC) and the API endorsed Center for Offshore Safety (COS) in order to

maintain a high level of communication with other GoM Operators and safety organizations.

Involvement with these organizations will ensure that Hess management and staff are not only

aware of existing regulations, but, aware and involved with the frequent change in the

regulatory environment in the GoM operating area.  

Contractors performing work for Hess are required to have safety and environmental policies

and practices that are consistent with the Hess SEMS program. Contractors may adopt

appropriate sections of the Hess SEMS program, through the use of a bridging document to

indicate agreement between the contractor and Hess.  

FOR PUBLIC RELEASE
Hess Corporation    Llano Field  

Supplemental EP    Garden Banks Block 386, OCS‐G10350

The Atwood Condor is designed and operated to meet or exceed acceptable environmental

regulatory standards to ensure protection of human health and the environment. The vessel has

been designed, built and classed in accordance with the rules of the International Maritime

Organization (IMO) and complies with the regulations of the International Convention of the

Prevention of Pollution from Ships (MARPOL). The vessel has also been designed and

constructed in accordance with United States Coast Guard (USCG) rules and regulations

pertaining to foreign flag vessels.

FOR PUBLIC RELEASE
Hess Corporation    Llano Field  

Supplemental EP    Garden Banks Block 386, OCS‐G10350

Attachment A‐1

BOEM‐0137:  OCS Plan Information Forms

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

Bureau of Ocean Energy Management 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: BOEM Operator Number: 

Address: Contact Person: 

 Phone Number: 

 E-Mail Address: 

Lease(s): Area: Block(s): Project Name (If Applicable): 

Objective(s): Oil Gas Sulphur Salt Onshore Base: Distance to Closest Land (Miles): 

Description of Proposed Activities (Mark all that apply)

Exploration drilling Development drilling 

Well completion Installation of production platform 

Well test flaring (for more than 48 hours) Installation of production facilities 

Installation of caisson or platform as well protection structure Installation of satellite structure 

Installation of subsea wellheads and/or manifolds Commence production 

Installation of lease term pipelines Other (Specify and describe) 

Have you submitted or do you plan to submit a Conservation Information Document to accompany this plan? Yes No 

Do you propose to use new or unusual technology to conduct your activities? Yes No 

Do you propose any facility that will serve as a host facility for deepwater subsea development? Yes No 

Do you propose any activities that may disturb an BOEM-designated high-probability archaeological area? Yes No 

Have all of the surface locations of your proposed activities been previously reviewed and approved by BOEM? Yes No 

Tentative Schedule of Proposed Activities 

Proposed Activity Start Date End Date No. of Days 

 

 

Description of Drilling Rig Description of Production Platform 

 Jackup Drillship Caisson Tension leg platform

 Gorilla Jackup Platform rig Well protector Compliant tower 

 Semisubmersible Submersible Fixed platform Guyed tower

 DP Semisubmersible Other (Attach Description) Subsea manifold Floating production system 

Drilling Rig Name (If Known): Spar Other (Attach Description) 

Description of Lease Term Pipelines 

From (Facility/Area/Block) To (Facility/Area/Block) Diameter (Inches) Length (Feet) 

 

FORM BOEM-0137 (October 2011 - Supersedes all previous editions of form BOEM-0137 which may not be used. 

*Collection has been submitted to OMB and is automatically renewed each month until approval.) Page 1 of 2

FOR PUBLIC RELEASE
FOR PUBLIC RELEASE
FOR PUBLIC RELEASE
FOR PUBLIC RELEASE
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 BOEM collects this information as part of an applicant’s Exploration Plan or Development Operations 

Coordination Document submitted for BOEM 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 550.197. 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, Bureau of Ocean Energy Management, 381 Elden Street, Herndon, VA 20170.

 

FORM BOEM-0137 (October 2011- Supersedes all previous editions of form BOEM-0137 which may not be used.) Page 2 of 2

FOR PUBLIC RELEASE
Hess Corporation    Llano Field  

Supplemental EP    Garden Banks Block 386, OCS‐G10350

Attachment A‐2

Surface Location Plat

FOR PUBLIC RELEASE
HESS CORPORATION

UNITED STATES OFFSHORE PRODUCTION

LLANO PROSPECT

GARDEN BANKS AREA

BLOCK 386 OCS-G-10350

BATHEMETRY & ANCHOR

DATE:1/2012

PUBLIC Llano_Bath_Anchor.mxd

Texas Louisiana

Alabama

Florida

Mississippi Georgia

GULF OF MEXICO

#

a

2

a 9

,

a

a

aa aa

a

a

a1

1

a

a

a a

1

# #

1

a

1

a

a

a1

ÃÃ

"LL-4"

PROP.

SURFACE

3,751.16' FWL

1,271.97' FSL

X=1,872,871.16

Y=10,012,151.97

27°35' 20.37"N

-92°16' 55.63"W

"LL-5"

PROP.

SURFACE

3,892.68' FWL

1,141.94' FSL

X=1,873,012.68

Y=10,012,021.94

27°35' 19.074"N

-92°16' 54.06"W

"LL-6"

PROP.

SURFACE

3,940.57' FWL

1,194.05' FSL

X=1,873,060.57

Y=10,012,074.06

27°35' 19.59"N

-92°16' 53.53"W

BLOCK 386

OCS-G-10350

BLOCK 430

BLOCK 387

OCS-G-30791

 BLOCK 342

 BLOCK 385

OCS-G-17358

BLOCK 429 BLOCK 431

OCS-G-26651

 BLOCK 343

BLOCK 341

OCS-G-15879

LL-6

LL-5

LL-4

-3000

-1500

EXPLORATION PLAN

0 2,000 4,000

Feet

È# HESS SURFACE LOCATION

LEGEND

FOR PUBLIC RELEASE
Hess Corporation    Llano Field  

Supplemental EP    Garden Banks Block 386, OCS‐G10350

Attachment A‐3

Bathymetry Maps

FOR PUBLIC RELEASE
FOR PUBLIC RELEASE
FOR PUBLIC RELEASE
FOR PUBLIC RELEASE
Hess Corporation    Llano Field  

Supplemental EP    Garden Banks Block 386, OCS‐G10350

Attachment A‐4

Pay.gov cost recovery fee receipt

FOR PUBLIC RELEASE
1

Kight, Brittany

From: paygovadmin@mail.doc.twai.gov

Sent: Friday, January 06, 2012 8:21 AM

To: Kight, Brittany

Subject: Pay.Gov Payment Confirmation

THIS IS AN AUTOMATED MESSAGE.  PLEASE DO NOT REPLY.

Transaction Summary

Application Name: BOEM Exploration Plan ‐ BF Pay.gov Tracking ID: 255CQD91 Agency Tracking ID: 74269406498

Transaction Type: Sale Transaction Date: Jan 6, 2012 9:20:57 AM

Account Holder Name: Brittany Kight

Transaction Amount: $10,326.00

Billing Address: 1501 McKinney Street

City: Houston

State/Province: TX

Zip/Postal Code: 77010

Country: USA

Card Type: AmericanExpress

Card Number: ************1008

Region: Gulf of Mexico

Contact: Brittany Kight 713‐775‐7817

Company Name/No: Hess Corporation, 00059 Lease Number(s): 10350, , , ,

Area‐Block: Garden Banks GB, 386: , : , : , : , Surface Locations: 3

FOR PUBLIC RELEASE
Hess Corporation    Llano Field  

Supplemental EP    Garden Banks Block 386, OCS‐G10350

Appendix B

General Information

(a) Applications and Permits  

Application/Permit Agency Status

Military Warning Area Activity

Notifications

Military Warning Areas 147AB

and 59A Pending

Rig Move Reports USCG, MWA and NGIA Pending

(b) Drilling Fluids

Type of Drilling Fluid Estimated Volume of Drilling Fluid to be

Used per Well

Water based ( sea water, fresh water, barite) See Appendix F:  Water Quality Tables

Oil based (diesel, mineral oil) N/A

Synthetic based (internal olefin, ester) See Appendix F:  Water Quality Tables

(c) Production

There is no production proposed under this plan; this section is applicable only to DOCDs.

(d) Oil Characteristics

There is no production proposed under this plan; this section is applicable only to DOCDs.

(e) New or Unusual Technology

Hess does not propose any new or unusual technology to be utilized as a result of the

operations proposed under this plan.

FOR PUBLIC RELEASE
Hess Corporation    Llano Field  

Supplemental EP    Garden Banks Block 386, OCS‐G10350

(f) Bonding Statement

The bond requirements for the activities and facilities proposed in this EP are satisfied by a

$3,000,000.00 area‐wide bond, furnished and maintained in accordance with 30 CFR Part 256,

subpart I; NTL No. 2000‐G16, “Guidelines for Lease Surety Bonds;” and a current BOEM‐

approved deferment from providing additional security under 30 CFR 553.5 (d) and National NTL

No. 2008‐N07, “Supplemental Bond Procedures.”  If, at any point, Hess Corporation no longer

qualifies for a supplemental bonding deferment, Hess Corporation will either provide the

required additional security or a third party guarantee within 60 days after such qualification.

(g) Oil Spill Financial Responsibility

Hess Corporation, BOEM Company Number 00059, has demonstrated oil spill financial

responsibility for the facilities proposed in this EP according to 30 CFR Part 253, and NTL No.

2008‐N05, “Guidelines for Oil Spill Financial Responsibility (OSFR) for Covered Facilities.”    

(h) Deepwater Well Control Statement

Hess Corporation, BOEM Company Number 00059, has the financial capability to drill a relief

well and to conduct other emergency well control operations.

(i) Suspensions of Production

There is no production proposed under this plan; this section is applicable only to DOCDs.

(j) Blowout Scenario

Although an uncontrolled blowout is considered extremely unlikely, the following is a response

scenario of an uncontrolled blowout event at GB 386.  

The scenario that presents the potential worst‐case discharge rate for the proposed wellbore is

expected to occur when the drill string has been pulled from the hole after having drilled

[PROPRIETARY INFORMATION OMITTED] through the objective sand with the last casing shoe at

[PROPRIETARY INFORMATION OMITTED].    It is assumed the well has experienced a kick and

attempts at initiating shut‐in procedures have failed, thus rendering the BOPs ineffective.  This

situation presents an unrestricted flow of hydrocarbons to surface with an initial flow rate of

228,936 BOPD within the first 24 hour period.    

The worst case discharge volume at GB 386 has been calculated as per the criteria in 30 CFR

254.44.  This potential volume would be an average 127,984 BOPD from the well for 30 days,

and assuming a conservative evaporation/dispersion rate of 25%, or 31,996 BBLS. (See Appendix

I‐5 Attachments – Oil Spill Response Discussion/Budget Table), this would leave approximately

95,988 BBLS of oil remaining on the surface for mechanical recovery, in‐situ burning, and/or

chemical dispersion. Based on aerial overflights and trajectory modeling showing predicted

shoreline impacts, environmental sensitivity and shoreline protection,  maps and strategies are

available for other areas with potential impact identified in the EIA.  

FOR PUBLIC RELEASE
Hess Corporation    Llano Field  

Supplemental EP    Garden Banks Block 386, OCS‐G10350

The analog data used for this prospect are the [PROPRIETARY INFORMATION OMITTED].   The

offset wells have logs, directional surveys, and wellbore schematics on file with the Bureau of

Ocean Energy Management and the Bureau of Safety and Environmental Enforcement.  All wells

are located within 2 miles of the proposed LL4, LL5 and LL6 well locations.

If a blowout were to occur at GB 386, Cameron Parish is identified as the most probable

impacted Parish within the Gulf of Mexico. Cameron Parish is located in the southwest corner of

Louisiana and has a total area of 1,932 square miles, of which, 1,313 square miles of it is land

and 619 square miles is water. Cameron Parish includes four National Wildlife Refuges including

the Cameron Prairie National Wildlife Refuge, East Cove National Wildlife Refuge, Sabine

National Wildlife Refuge and part of the Lacassine National Wildlife Refuge. Examples of

Environmental Sensitivity maps for Cameron Parish are included under Appendix B‐1

Attachments.

Maximum Duration of the Potential Blowout

Hess’ multi‐disciplinary team calculated that an initial worst case blowout scenario with the

[PROPRIETARY INFORMATION OMITTED] reservoir open would be a maximum of 228,936

barrels of 33.1° gravity oil.  In such a scenario, the potential for the well to bridge is very high

and bridging of the open hole interval is expected to occur within 1 hour of an uncontrolled

blowout due to wellbore failure of the surrounding shale.  

The total estimated volume of oil from the initial blowout, until the depletion of reservoir

pressure after 137 days, is estimated to be 13,198,731 BBLS.   

(125,702.2 BOPD)    (138 days to reservoir pressure depletion) = (17,346,903.6) (1  ‐  .25) =

13,010,177 BBLS of oil left in water.  The average oil rate of BOPD is derived from an initial rate

of 228,936 BOPD which declines to 23,008.4 after 138 days.

Discussion of Likelihood for Surface Intervention to Stop Blowout

The LL5ST will be drilled in Garden Banks Block 386 as a subsea well in approximately 2,700’ of

water with the wellhead and BOP equipment located at the mudline.    Surface intervention

would be the preferred method of intervention pending an uncontrolled blowout, however the

technique used would be contingent upon the condition of the rig, marine riser system and BOP

equipment.    Surface intervention is a quicker solution than drilling a relief well, but actual

methodology of controlling the blowout would have to be determined pending an analysis of

the site‐specific conditions at the location.   

A team of specialists would be mobilized immediately to assess the situation and determine a

corrective course of action to control the blowout.    Well control specialists would perform

either a fly‐by via helicopter and/or surface vessel to assess conditions at the site.    Hess

Corporation has Master Service Agreements with Wild Well Control and Boots and Coots.  An

ROV spread capable of manipulating the rig’s BOP hot‐stab functions would be mobilized to

location and, if appropriate, an attempt would be made to shut in the well by closing the blind

shear rams.    These actions would take place within 24  ‐  48 hours of the incident.    Initial

FOR PUBLIC RELEASE
Hess Corporation    Llano Field  

Supplemental EP    Garden Banks Block 386, OCS‐G10350

assessment activities are projected to take 3 – 5 days.  During this period, the well control team

would analyze the blowout situation, devise an intervention strategy and mobilize additional

service company specialists, supplies and equipment.  A field support base in Fourchon, LA and

secondary command center near the coast would be arranged and would have communication

established simultaneously during this assessment period.

Discussion of the Likelihood of Subsea Intervention to Stop the Blowout:

The GC 386 LL5ST will be drilled as a subsea well in approximately 2,700’ of water with the

wellhead and BOP equipment located at the mudline.  Subsea interference would be the likely

method of intervention pending an uncontrolled blowout, however the technique used would

be contingent upon the condition of the rig, marine riser system and BOP equipment.  An ROV

may be used to shift the blind/shear rams in the BOP stack to the closed position, thereby

allowing the damaged riser system to be removed and a capping mechanism to be put in place.  

Hess Corporation has contract in‐place with Marine Well Containment Company (MWCC).   In

the event of a blowout, a capping stack would be mobilized to location.  If discharge is occurring

at a rate that prevents the well from being shut in, hydrocarbon collection at the source would

occur during relief well drilling operations.

Discussion of Drilling a Relief Well:

Hess Corporation (Company No. 00059) has the financial capability to drill a relief well and

conduct other emergency well control operations. Should a relief well be necessary, there are

deepwater rigs rated and equipped to drill in water depths of 2,700’ or greater. Since most of

these rigs are MODUs, the time necessary to get to the location is minimal. The time required to

drill the relief well will be dependent on many factors, chief among them is the required depth

of the relief well.    The deepest anticipated depth of the relief well would be in the situation

where it was required to intersect the blown‐out well at its final target depth (TD).    The

probable directional nature of the relief well could nominally increase its measured depth

compared to the blown‐out well.  The time required to drill this extra distance is anticipated to

be more than offset by the better understanding of the optimum drilling parameters learned

while drilling the blown‐out well.  In order to intersect the blowout well, numerous ranging runs

will be required which will add approximately three weeks to the drilling program.  The steps

and time required to accomplish the dynamic kill are also dependent on the particular

circumstances of the blown‐out well.

FOR PUBLIC RELEASE
Hess Corporation    Llano Field  

Supplemental EP    Garden Banks Block 386, OCS‐G10350

It is assumed that a rig is not immediately available to mobilize to location to commence drilling

a relief well.    The estimated mobilization time of a rig to the GB 386 wellsite locations

incorporates the suspension of activities by another operator before the rig can be released for

relief well operations.    Hess Corporation will support relief well drilling operations using in‐

house resources supplemented with diversified engineering consulting firms which would

provide drilling operations, engineering, logistical and materials management; QA/QC and well‐

site supervision support.    In addition, Hess Corporation will select a well control specialty

company and prepare a conceptual “Relief Well Plan” specific to the GC 386 LL5ST.  The plan will

address the calculated blowout rate, selection of surface location, directional planning intercept

strategy and dynamic kill design.    Casing design, directional drilling, trajectory planning and

magnetic ranging techniques, as well as multiphase simulation of the blowout will be

considering factors in planning the relief well.   

Rig Package Restraints:

 The rig chosen to drill the relief well must be capable of operating in water depths of

2,700’ of water.  

 The rig chosen to drill the relief well must have a BOP package acceptable and certified

under current BOEM/BSEE regulations.

 There are no facilities within the surrounding area of well locations; therefore, a relief

well will be unable to be drilled from a nearby platform.

 Due to the proximity to shore (~130 miles) a relief well cannot be drilled from an

onshore location.

  

FOR PUBLIC RELEASE
Hess Corporation    Llano Field  

Supplemental EP    Garden Banks Block 386, OCS‐G10350

Rigs Capable of Drilling a Relief Well:

Rig Type Contractor Rig Name

DRILLSHIP           TRANSOCEAN            DW PATHFINDER        

DRILLSHIP           TRANSOCEAN            DISCOVERER DEEP SEAS

DRILLSHIP           TRANSOCEAN            GSF C.R. LUIGS       

DRILLSHIP           TRANSOCEAN            DISCOVERER INDIA     

DRILLSHIP           TRANSOCEAN            DISCOVERER AMERICAS  

DRILLSHIP           TRANSOCEAN            CLEAR LEADER         

DRILLSHIP           TRANSOCEAN            INSPIRATION          

DRILLSHIP           ENSCO                 ENSCO DS‐5           

SEMI SUBMERSIBLE    DIAMOND OS            OCEAN VICTORY        

SEMI SUBMERSIBLE    NOBLE DRLG            JIM THOMPSON         

SEMI SUBMERSIBLE    NOBLE DRLG            NOBLE AMOS RUNNER    

SEMI SUBMERSIBLE    TRANSOCEAN            GSF DD I             

SEMI SUBMERSIBLE    TRANSOCEAN            GSF DD II            

SEMI SUBMERSIBLE    TRANSOCEAN            DW NAUTILUS          

SEMI SUBMERSIBLE    ENSCO                 ENSCO 8502           

SEMI SUBMERSIBLE    ENSCO                 ENSCO 8500           

SEMI SUBMERSIBLE    ENSCO                 ENSCO 8501           

SEMI SUBMERSIBLE    MAERSK DRILLING       MAERSK DEVELOPER     

SEMI SUBMERSIBLE    ENSCO                 ENSCO 8503           

SEMI SUBMERSIBLE    ENSCO                 ENSCO 8503           

SEMI SUBMERSIBLE    SEADRILL              WEST SIRIUS          

SEMI SUBMERSIBLE    NOBLE                 NOBLE JIM DAY        

SEMI SUBMERSIBLE    NOBLE                 NOBLE DANNY ADKINS   

There are currently 23 individual rigs currently working in the Gulf of Mexico that are capable of

drilling a relief well at this location.

FOR PUBLIC RELEASE
Hess Corporation    Llano Field  

Supplemental EP    Garden Banks Block 386, OCS‐G10350

Blowout Prevention and Likelihood Reduction Measures:

In addition to 30 CFR 250, these additional measures will be taken in order to prevent and

reduce the likelihood of a blowout and conduct effective and early intervention in the event of a

blowout as described by Notice to Lessees 2010‐N06.

 Hess Corporation will verify with contractor that all BOPs have been certified, maintained and

are capable of operating in the anticipated conditions required for operations.

 Hess Corporation representative will witness and review all BOP tests, casing tests and

formation integrity tests.

 Hess Corporation representative will review and witness the installation, testing, function

testing and operation of the diverter system and diverter outlets.

 Key personnel on the rig will have a valid well control certificate.

 A liner top packer or equivalent expandable will be run on all liner laps as an additional barrier

for well safety.

 Every effort will be made to review all offset and seismic data in order to prepare a mud weight

schedule that will allow for safe drilling margin without putting excess hydrostatics pressures on

known zones previously encountered.

 Lost circulation material will be added to the mud system in order to assist the mud system’s

ability to prevent lost circulation. Sweeps and concentrated pills will be used to prevent

uncontrolled mud losses.

 Wiper trips will be performed as hole conditions dictate in order to quantify the stability of the

wellbore and to determine whether sufficient mud weights are being utilized.

 Connections will be simulated as needed while drilling into pressure transition areas in order to

properly assess the current wellbore conditions.

 Mudloggers may be utilized during critical drilling operations to monitor gas content of mud

returns, formation characteristics and abnormalities of cuttings and to estimate paleo aging of

cuttings.

 Logging While Drilling (LWD) tools will be utilized as much as possible to evaluate formations,

formation pressures and fluid content in the critical sections of the well.

 Log data will be continuously reviewed by Hess Corporation’s drilling and geological

departments.

Key Reservoir Data used for NODAL Modeling:

The calculated worst case discharge rate of 228,936 barrels of 33.1° gravity oil in the first 24‐

hour period is based on the wellbore having an uncontrolled blowout from formations in open‐

hole with the last casing shoe at [PROPRIETARY INFORMATION OMITTED]    as detailed on the

wellbore schematic.

The GB 386 LL5ST is expected to be an oil well with a relatively high GOR and was modeled as

such in using Petroleum Experts Integrated Production Modeling Software (v. 7.5).

[PROPRIETARY INFORMATION OMITTED]    When the required data cannot be extracted from

public sources, sound engineering practices and experience were used to build the input data in

the Nodal analysis.  [PROPRIETARY INFORMATION OMITTED]

FOR PUBLIC RELEASE
Hess Corporation    Llano Field  

Supplemental EP    Garden Banks Block 386, OCS‐G10350

Attachment B‐1

Environmental Sensitivity Maps for Cameron Parish

FOR PUBLIC RELEASE
FOR PUBLIC RELEASE
FOR PUBLIC RELEASE
Hess Corporation    Llano Field  

Supplemental EP    Garden Banks Block 386, OCS‐G10350

Appendix C

Geological and Geophysical Information

  

(a) Geological Description

[PROPRIETARY INFORMATION OMITTED]   

(b) Structure Contour Maps

[PROPRIETARY INFORMATION OMITTED]  

(c) Interpreted 2‐D and/or 3‐D Seismic Lines

[PROPRIETARY INFORMATION OMITTED]   

(d) Geological Structure Cross‐Sections

[PROPRIETARY INFORMATION OMITTED]   

(e) Shallow Hazards Report

Numerous reports describing the geologic and geotechnical conditions within and surrounding

the Garden Banks 386 area were produced between August, 1998 and June, 2003 (C&C

Technologies, 2003; Fugro Geoservices, 1998a, 1998b, 1999, and 2000; GEMS, 2002). These

reports were used as the basis for Shell Gulf of Mexico Inc.’s, Supplemental DOCD (S‐7430)

approved September 1, 2009. The existing data was reassessed in December 2009 and revised

wellsite clearance assessments were submitted within Hess’ DOCD R‐4996 (GEMS, 2009).  

(f) Shallow Hazards Assessment

Included as Attachment C‐4, are Shallow Hazard and Archaeological Assessments (GEMS, 2012)

based on the high‐resolution geophysical data that was previously submitted to MMS, as well as

the AUV data acquired by Fugro in 2011 (Report #2411‐5009) that was submitted by Shell Gulf

of Mexico Inc. under separate cover in March 2012. These assessments are intended to

supplement the existing geohazard reports with additional details pertaining directly to the

seafloor and subsurface conditions within a 2,000’ radius of the LL4, LL5 and LL6 well locations.

These assessments also include a review of the 2011 high resolution geophysical data collected

by Fugro Geoservices, Inc. The data was collected using the Fugro Enterprise AUV. The data

consist of AUV side‐scan sonar, AUV subbottom profiler and AUV multibeam bathymetry data

sets. The full report (#2411‐5009) dated January 4, 2012 was submitted to BOEM by Shell Gulf of

Mexico Inc. under separate cover.

(g) High‐resolution Seismic Lines

[PROPRIETARY INFORMATION OMITTED]

                                                                                                                                                                                                           

FOR PUBLIC RELEASE
Hess Corporation    Llano Field  

Supplemental EP    Garden Banks Block 386, OCS‐G10350

(h) Stratigraphic Column

[PROPRIETARY INFORMATION OMITTED]

(i) Time vs. Depth Tables

Sufficient well control data for the target areas proposed in this Supplemental EP exists;

therefore seismic time versus depth tables for the proposed well locations are not required.

FOR PUBLIC RELEASE
Hess Corporation    Llano Field  

Supplemental EP    Garden Banks Block 386, OCS‐G10350

Attachment C‐4

Shallow Hazards Assessments

FOR PUBLIC RELEASE
10615 Shadow Wood Drive, Suite 200 

Houston, Texas 77043

713.468.1410[o] 713.468.1438 [f] 

www.gemsinc.com 

February 06, 2012 Project No. 0911-1995 

Hess Corporation 

1501 McKinney Street 

Houston, TX 77010

Attention: Mr. Mark Romanchock 

Site Clearance Letter 

Proposed Wellsite LL4 

Block 386 (OCS-G-10350) 

Garden Banks Area 

Gulf of Mexico 

Hess Corporation (Hess) contracted Geoscience Earth & Marine Services, Inc.®, (GEMS) to prepare a 

Site Clearance Letter for the Proposed Wellsite LL4 in Block 386 (OCS G-10350), Garden Banks (GB) 

area. This letter addresses specific seafloor and subsurface geologic conditions around the proposed 

location. The Proposed Wellsite LL4 constitutes the newest phase of development of the Llano field and 

lies within 2,030 ft to 9,930 ft of current Llano infrastructure.

The surface location of the LL4 wellsite lies in the southwestern portion of GB 386. Hess provided the 

following coordinates: 

Proposed Wellsite LL4

Spheroid & Datum: Clarke 1866, NAD27

Projection: UTM Zone 15 North Line Reference Block Calls

X: 1,872,871.16 ft Latitude: 27o 35’ 20.37317” N Inline 3819 3,751 ft FWL

Y: 10,012,151.97 ft Longitude: 92o 16’ 55.62867” W Crossline 4568 1,272 ft FSL

Hess plans to drill this well using a dynamically positioned semisubmersible rig. This assessment 

addresses the seafloor conditions within a 2,000-ft radius around the proposed wellsite location. 

Numerous reports describing the geologic and geotechnical conditions within and surrounding the 

GB 385 and 386 area were produced between August, 1998 and June, 2003 (C&C Technologies, 2003; 

Fugro Geoservices, 1998a, 1998b, 1999, and 2000; GEMS, 2002). These reports were used as the basis 

for Shell Gulf of Mexico Inc.’s, Supplemental Development Operations Coordination Document (DOCD) 

plan to clear proposed wells LL3 and LL4, submitted July 22, 2009. Due to the age of the reports, a new 

assessment of the area using improved seismic data was initiated by Hess to provide an updated 

geological prognosis for the clearance of a revised LL3 location, submitted in December 2009 (GEMS, 

2009). This current assessment is intended to supplement the existing geohazard reports with additional 

details pertaining directly to the seafloor and subsurface conditions surrounding the LL4 well location. 

This assessment also includes a review of the recently acquired high-resolution geophysical data 

collected by an AUV (Autonomous Underwater Vehicle). The data consist of multibeam echosounder, 

side-scan sonar, and subbottom profiler. 

Attachments 

The page-size maps and figures accompanying this letter have been extracted from the seismic 3-D 

volume and high-resolution AUV data supplied by Hess for the geohazard site assessment. These 

illustrations are centered on the LL4 location. 

Map No. GB386-LL4-1: Bathymetry Map 

FOR PUBLIC RELEASE
LL4 Site Clearance Letter 

Hess Corporation // February 06, 2012

Geoscience Earth & Marine Services, Inc. ® // 2 

FORUM ENERGY TECHNOLOGIES, INC. 

 Map No. GB386-LL4-2: Seafloor Rendering 

Map No. GB386-LL4-3: Side-Scan Sonar Mosaic 

Map No. GB386-LL4-4: Side-Scan Sonar Mosaic-Interpreted 

Map No. GB386-LL4-5: Geologic Features Map 

Figure GB386-LL4-1: Power Spectrum Analysis Curve, Proposed Wellsite LL4 (embedded) 

Figure GB386-LL4-2: Unidentified Side-Scan Sonar Contact Number 1 (embedded) 

Figure GB386-LL4-3: Unidentified Side-Scan Sonar Contact Number 2 (embedded) 

Figure GB386-LL4-4: Unidentified Side-Scan Sonar Contact Number 3 (embedded) 

Figure GB386-LL4-5: Side-Scan Sonar Mosaic Showing Drag Scars and Associated 

 Depressions (embedded) 

Figure GB386-LL4-6: Subbottom Profiler Line 124 Illustrating Disturbed Seafloor Caused by 

 Previous Exploration Activity 

Figure GB386-LL4-7: Subbottom Profiler Line 126 Illustrating the Shallow Stratigraphic 

 Conditions at the Proposed LL4 Location 

Figure GB386-LL4-8: Portions of Inline 3819 and Crossline 4568 Showing Conditions Beneath 

 Proposed Wellsite LL4 

Figure GB386-LL4-9: Tophole Prognosis Chart, Proposed Wellsite LL4, Garden Banks, 

 Block 386

Figure GB386-LL4-10: Vertical Profile Showing Stratigraphic Conditions Between Existing Wells 

 and the Proposed LL4 Location 

NTL Requirements

The following letter complies with the Bureau of Ocean Energy Management (BOEM) Notice to Lessees 

(NTL’s) 2008-G04, 2008-G05, and 2009-G40, (MMS, 2008a, b and 2010). The Federal lease block 

GB 386 is not considered archaeologically significant (BOEM, 2011); therefore, requirements set forth in 

NTL 2005-G07 are not applicable (MMS, 2005). However, pursuant to the recently released “Pre-Seabed 

Disturbance Survey Mitigation” issued by BOEM, an archaeological assessment of the data must be 

performed prior to any bottom-disturbing activities. 

Power Spectrum. According to NTL 2008-G05 (MMS, 2008a), 3-D seismic reflection data may be used 

for shallow hazard assessments with approval from the BOEM, Gulf of Mexico Region. A power 

spectrum analysis was conducted from the 3-D seismic data cube provided by Hess to illustrate the data 

parameters. The power spectrum curve was generated within 500-ft radius of the intersection of the 

inline and crossline at the proposed wellsite (Figure GB386-LL4-1). We converted the amplitude vs. 

frequency spectrum, generated by the SMT software, to power vs. frequency by squaring the amplitude 

values as described by J. A. Coffeen, 1978. 

 

Figure GB386-LL4-1: 

Power Spectrum 

Analysis Curve, 

Proposed Wellsite LL4

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

0 10 20 30 40 50 60 70 80 90 100 110 120

Amplitude

Frequency (Hz)

POWER SPECTRUM

FOR PUBLIC RELEASE
LL4 Site Clearance Letter 

Hess Corporation // February 06, 2012

Geoscience Earth & Marine Services, Inc. ® // 3 

FORUM ENERGY TECHNOLOGIES, INC. 

Man-Made Features

The Proposed Wellsite LL4 is planned for the Llano field in GB 386. Several wells have previously been 

drilled near the planned LL4 location in both GB 385 and 386. Table 1 provides a summary of the 

exploration wells drilled within three miles of the proposed LL4 well:

Table 1: Existing Wells Near Proposed Location 

Surface Area/ 

Block Well Name Operator Well Status Distance/Direction From Proposed LL4

GB 386 1 Shell Gulf of Mexico, Inc. Temporarily 

Abandoned 2,030 ft/W

GB 386 2 Shell Gulf of Mexico, Inc. Temporarily 

Abandoned 5,658 ft/ENE

GB 385 LL003 Shell Gulf of Mexico, Inc. Completed 6,400 ft/NW

GB 385 LL001 Shell Gulf of Mexico, Inc. Completed 6,595 ft/NW

GB 385 LL002 Shell Gulf of Mexico, Inc. Completed 9,930 ft/NW

 *Note: Latest infrastructure update from the Bureau of Ocean Energy Management (BOEM) database on 

January, 2012 (BOEM, 2012). 

Shell’s Auger TLP serves as the processing platform for the Llano field. Several existing pipelines trend 

generally southwest from existing Llano wells in GB 385 to the Auger platform in GB 426. Two Shell 8-

inch oil pipelines, one originating from a manifold near the LL1 and LL3 wells and the other from a 

manifold near the LL2 well, trend southwest to GB 426. Shell’s 5-inch umbilical generally trends 

northeastward from the Auger platform to near the existing LL1 and LL3 locations. Two in-field pipelines, 

an 8-inch oil and 5-inch umbilical line, lie between the LL1 and LL2 wells. These pipelines lie over

6,400 ft northwest of the proposed LL4 location.

Archaeological Assessment 

Hess contracted GEMS to examine the high-resolution AUV data collected by Fugro GeoServices, Inc. for 

potential archaeological contacts and avoidances at and immediately surrounding the proposed LL4 well 

location. Unidentified sonar contacts delineated near the proposed location are interpreted to be modern 

debris from nearby lease activity. 

Available Data. High-resolution multibeam bathymetry, subbottom profiler, and side-scan sonar data 

were collected by Fugro for Noble from September 26 – October 14, 2011. Hess provided the side-scan 

sonar, subbottom profiler, and multibeam digital data sets to GEMS for interpretation and reporting 

purposes. 

The AUV survey lines consisted of 120 kHz side-scan sonar data, 2-12 kHz Chirp subbottom data, and 

3m-bin multibeam bathymetry data. The primary AUV lines were spaced at 200 meters providing 100% 

overlap or 200% coverage on all primary lines. The AUV tie lines were spaced at 900 meters. Thirteen 

(13) high-resolution AUV side-scan sonar lines were reviewed for this assessment. The reviewed lines 

pass within 50-900 meters of the proposed LL4 location. Lines 124-131, 211-212, and 400-402 were 

reviewed for potential cultural resources. 

The digital data for the Llano Prospect proposed LL4 well was examined for archaeological contacts 

using Chesapeake Technologies’ SonarWiz 5 software. Targets were identified and mapped in SonarWiz 

before being exported to MapInfo and then to AutoCAD for incorporation on the Archaeological 

Assessment Map. The side-scan sonar mosaic and bathymetric contours were generated from the Fugro 

survey data. Three unidentified side-scan sonar contacts were delineated in the data within 3,120 ft from 

the proposed well location. Sonar Contact Number 2 is 2,350 ft from the proposed well; however, no 

potential cultural resources are delineated within 2,500 ft of the proposed well location (Figures GB386-

LL4-4 and GB386-LL4-5). 

FOR PUBLIC RELEASE
LL4 Site Clearance Letter 

Hess Corporation // February 06, 2012

Geoscience Earth & Marine Services, Inc. ® // 4 

FORUM ENERGY TECHNOLOGIES, INC. 

Archaeological Avoidance. No archaeological avoidances exist within the area of potential effect for 

the proposed GB 386 LL4 well. No known shipwrecks lie within the area of potential effect.

Proposed Well LL4. The proposed LL4 well is located in the southwestern corner of Garden Banks 

Block 386, 2,625 ft below Mean Sea Level (MSL). Three unidentified side-scan sonar contacts were 

delineated within 3,120 ft of the proposed well location (Table 2 and Figures GB386-LL4-2 through 

GB386-LL4-4). 

Table 2: Unidentified Side-Scan Sonar Contacts Located Within 3,120 ft of the Proposed Well 

Number Area/ 

Block Description Length (ft)

Width 

(ft)

Height 

(ft)

X (ft) Y (ft)

1 GB 386 Linear 21.98 9.84 0.00 1,869,954.00 10,011,389.28

2 GB 386 Circular 30.51 26.25 0.00 1,872,017.81 10,014,375.80

3 GB 430 Linear 12.13 4.26 0.00 1,875,440.51 10,010,640.17

Unidentified Side-Scan Sonar Contact Number 1 is a linear contact measuring approximately 22 ft long, 

10 ft wide, and displays no measurable height (Figure GB386-LL4-2). The contact is interpreted to 

represent debris from the nearby Shell #1 well. This contact is not recommended for archaeological 

avoidance or investigation. 

Figure GB386-LL4-2: Unidentified Side-Scan Sonar Contact Number 1 

Unidentified Side-Scan Sonar Contact Number 2 is a circular contact measuring approximately 30 ft long, 

and 26 ft wide (Figure GB386-LL4-3). The contact is interpreted to represent seafloor debris from the 

nearby well. This contact is not recommended for archaeological avoidance or investigation. 

FOR PUBLIC RELEASE
LL4 Site Clearance Letter 

Hess Corporation // February 06, 2012

Geoscience Earth & Marine Services, Inc. ® // 5 

FORUM ENERGY TECHNOLOGIES, INC. 

Figure GB386-LL4-3: Unidentified Side-Scan Sonar Contact Number 2 

Unidentified Side-Scan Sonar Contact Number 3 is a linear contact measuring approximately 12 ft long, 

and 4 ft wide (Figure GB386-LL4-4). The contact is interpreted to represent seafloor debris. This contact 

is not recommended for archaeological avoidance or investigation. 

Figure GB386-LL4-4: Unidentified Side-Scan Sonar Contact Number 3 

Several areas of drag scars consisting of shallow depressions and low mounds were imaged in the sidescan sonar data and can be seen on the sonar mosaic as darker returns. None of these areas represent 

side-scan sonar contacts. Each area was examined in the side-scan sonar and multibeam bathymetry 

before being eliminated as a possible side-scan sonar contact. The drag scars are in proximity to the 

previously drilled Shell well and likely represent previous anchoring activities (Figure GB386-LL4-5).

FOR PUBLIC RELEASE
LL4 Site Clearance Letter 

Hess Corporation // February 06, 2012

Geoscience Earth & Marine Services, Inc. ® // 6 

FORUM ENERGY TECHNOLOGIES, INC. 

Figure GB386-LL4-5: Side-Scan Sonar Mosaic Showing Drag Scars and Associated Depressions 

No potential cultural resources are identified within the reviewed data surrounding the proposed LL4 well 

location in GB 386. 

Findings. Based on the available high-resolution geophysical data no potential submerged cultural 

resources were delineated in the area of potential effect. No unidentified side-scan sonar contacts were 

delineated in this data review within 3,120 ft of the proposed LL4 well.

Wellsite Conditions 

The surface location is clear of any geologic constraining conditions within a 2,000 ft radius of the 

proposed wellsite. 

Water Depth and Seafloor Conditions. Seafloor conditions are favorable at the proposed wellsite 

location. The water depth at the proposed surface location is approximately -2,625 ft and the seafloor 

slopes to the south-southwest at about 4.4° (Map GB386-LL4-1). The Proposed Wellsite LL4 lies along 

the base of a shallow salt topographic high (Map GB386-LL4-2). Seafloor conditions at the proposed 

location appear to be relatively smooth. Subtle gullies and lobate features highlighted on the seafloor 

rendering are likely associated with buried debris flow events originating from the topographic high to the 

north. A surficial drape of normally consolidated soft clays likely covers the seafloor at the location. 

Several areas of disturbed seafloor (shallow depressions and mounds) are located within 2,000 ft of the 

proposed LL4 location (Figure GB386-LL4-6). The closest area of disturbed seafloor to the proposed 

surface location is approximately 290 ft to the northeast (Maps GB386-LL4-3 and GB386-LL4-4). These 

areas are not related to hydrocarbon seepage and are likely associated with previous anchoring activities 

from nearby wells (Figure GB386-LL4-6). 

Deepwater Benthic Communities. Even though GB 386 is a designated chemosynthetic block, there 

are no features or areas that could support significant deepwater benthic communities within 2,000 ft of 

the proposed location (Maps GB386-LL4-3 and GB386-LL4-4), MMS, 2010. The possible hydrocarbon

Shell #1 Well

Drag Scars and Depressions

GB 385 GB 386

GB 429 GB 430

N

FOR PUBLIC RELEASE
LL4 Site Clearance Letter 

Hess Corporation // February 06, 2012

Geoscience Earth & Marine Services, Inc. ® // 7 

FORUM ENERGY TECHNOLOGIES, INC. 

seep related areas (characterized by high-amplitude returns and/or rough seabed texture) occur more 

than 2,000 ft northeast of the proposed LL4 well location (Maps GB386-LL4-3 and GB386-LL4-4). 

Stratigraphy. Stratigraphic conditions are shown on Figures GB386-LL4-7 through GB386-LL4-9. The 

seafloor and near surface sediments at the Proposed Wellsite LL4 are expected to be a pelagic clay 

drape overlying hemipelagic clays and silty clays interbedded with thin, clay-prone mass-transport 

deposits (Figure GB386-LL4-7). Some of the shallow mass-transport deposits may be associated with 

failure events from the adjacent topographic high. 

In general, the sediments below the seafloor to the limit of investigation (5,651 ft bml or 8,276 ft bsl)

consist primarily of hemipelagic clays and mud-dominated turbidite deposits. Interbedded in places within 

the generally stratified section are discontinuous units of clay-prone mass-transport deposits. Well logs 

from the existing LL1 and LL2 wells illustrate a clay-dominated shallow section (Figure GB386-LL4-10);

however, occasional thin silt or sand seams may be encountered below 1,406 ft bml to the limit of 

investigation (5,651 ft bml) at the proposed site. 

Faults. No seafloor or buried faults will be penetrated by the Proposed Wellsite LL4 in the shallow 

section to the limit of investigation (Figures GB386-LL4-7 through GB386-LL4-9). A series of faults are 

evident on the seafloor rendering and subbottom profiler lines north and northeast of the proposed 

surface location (Map GB386-LL4-2). The closest of these faults to the proposed location is 

approximately 1,340 ft to the northeast. The faults appear to be draped by approximately 10 to 25 ft of 

sediment and are downthrown to the east, away from a vertical borehole at the LL4 location. 

Shallow Gas and Shallow Water Flow. Significant shallow gas is not expected at this proposed 

wellsite (Figures GB386-LL4-8 and GB386-LL4-9). The potential for shallow water flow at this well 

location is negligible to low. 

 Shallow Gas. There are no apparent subsurface high-amplitude anomalies directly below the 

proposed wellsite (Map GB386-LL4-5). The potential for encountering shallow gas is considered 

negligible in the clay-prone unit between the seafloor and 1,406 ft bml. There is a low potential for 

encountering minor amounts of biogenic gas within thin coarse-grained layers between 1,406 ft to the 

limit of investigation (5,651 ft bml). 

Shallow Water Flow. The potential for shallow water flow at this well location is negligible to low 

(Figure GB386-LL4-9). The five Llano exploration wells across GB 385 and 386 (approximately 2,030 ft 

to 9,930 ft from the proposed location), did not report water flow conditions during drilling operations. 

Generally, similar stratigraphic units are expected to be penetrated at the proposed LL4 location (Figure 

GB386-LL4-10). A section of thin sands may be encountered within mass-transport deposits between 

1,406 ft and 1,781 ft bml at the proposed location (Figure GB386-LL4-9). However, these possible sands 

are not likely to produce sustained flow. The shallow water flow potential for this unit is considered low. 

The remaining, generally clay-rich section has a negligible potential for overpressured sands. 

Closing 

The Proposed Wellsite LL4, Garden Banks Block 386, appears suitable for exploration drilling operations. 

No major hazards or constraints are defined by the 3-D or high-resolution AUV data at the proposed 

location. 

Additionally, no potential submerged cultural resources exist within 3,120 ft of the proposed LL4 location. 

Should any potentially historic materials such as textiles, wood, ceramics, or other items be uncovered 

during operations in the area, all operations must cease and BOEM be notified within 48 hours. 

 

FOR PUBLIC RELEASE
LL4 Site Clearance Letter 

Hess Corporation // February 06, 2012

Geoscience Earth & Marine Services, Inc. ® // 8 

FORUM ENERGY TECHNOLOGIES, INC. 

Sincerely, 

GEOSCIENCE EARTH & MARINE 

SERVICES, INC.®

Oluwayomi Oyedele Daniel Lanier 

Geoscientist Vice President-Geosciences 

Kimberly L. Faulk, MA Erin Williams Janes 

Senior Marine Archaeologist Senior Geoscientist/Project Manager 

Attachments (5 Maps and 5 Figures) 

Distribution: 

Mr. Mark Romanchock, Hess Corporation (8 copies) 

REFERENCES 

Bureau of Ocean Energy Management, 2012, ASCII Data Files, published on the BOEM Gulf of Mexico Region Homepage, 

<http://www.gomr.boerme.gov/homepg/pubinfo/freeasci/freedesc.html>, Accessed January, 2012. 

Bureau of Ocean Energy Management, 2011, Notice to lessees and operators of federal oil and gas leases and pipeline 

right-of-way holders on the outer continental shelf, Revisions to the list of OCS lease blocks requiring archaeological 

resource surveys and reports: U. S. Department of the Interior, Bureau of Ocean Energy Management, Bureau of Safety 

and Environmental Enforcement, Gulf of Mexico, NTL 2011-JOINT-G01. Effective Date December 29, 2011. 

C&C, 2003, Engineering and hazard study report, Garden Banks blocks 385 and 426, C&C Technologies, project no. 3567-

3663, dated June 2003. 

Coffeen, J. A., 1978, Seismic Exploration Fundamentals: Tulsa, the Petroleum Publishing Co., p. 125. 

Fugro, 1998a, Geohazards Assessment, blocks 297, 298, 341, 342, 385, and 386, Garden Banks area, Fugro Geoservices, 

project no. 0201-3669, dated August 20, 1998. 

Fugro, 1998b, Geotechnical investigation, blocks 385 and 386, Garden Banks area, Gulf of Mexico, Fugro Geoservices, 

project no. 0201-3636-1, dated September, 1998. 

Fugro, 1999, Report on blocks 345, 346, 389, and 390, Garden Banks area, Gulf of Mexico, Fugro Geoservices, project no. 

0201-3755, dated March, 1999. 

Fugro, 2000, Shallow hazards report, OCS-G no. 15880, block 342, Garden Banks area, Gulf of Mexico, Fugro Geoservices, 

project no. 2499-2054, dated January 2000. 

GEMS, 2002, Preliminary pipeline planning study, Garden Banks block 385, Gulf of Mexico, Geoscience Earth & Marine 

Services, Inc., project no. 1101-458, dated February, 2002. 

GEMS, 2009, Site clearance letter and anchoring considerations for proposed wellsite LL3, block 385, Garden Banks Area, 

Gulf of Mexico, Geoscience Earth & Marine Services 

Minerals Management Service, 2005, Notice to lessees and operators of federal oil, gas, and sulphur leases and pipeline 

right-of-way holders in the outer continental shelf, Gulf of Mexico OCS region, Archaeological resource surveys and reports: 

U. S. Department of the Interior, Minerals Management Service, Gulf of Mexico, NTL 2005-G07. Effective Date July 1, 

2005. 

Minerals Management Service, 2008a, Notice to lessees and operators of federal oil, gas, and sulphur leases in the outer 

continental shelf, Gulf of Mexico OCS region, information requirements for exploration plans and development operations 

coordination documents: U. S. Department of the Interior, Minerals Management Service, Gulf of Mexico, NTL 2008-G04. 

Effective Date May 1, 2008. 

FOR PUBLIC RELEASE
LL4 Site Clearance Letter 

Hess Corporation // February 06, 2012

Geoscience Earth & Marine Services, Inc. ® // 9 

FORUM ENERGY TECHNOLOGIES, INC. 

Minerals Management Service, 2008b, Notice to lessees and operators of federal oil, gas, and sulphur leases and pipeline 

right-of-way holders in the outer continental shelf, Gulf of Mexico OCS region, shallow hazards program: U. S. Department 

of the Interior, Minerals Management Service, Gulf of Mexico, NTL 2008-G05. Effective Date May 1, 2008. 

Minerals Management Service, 2010, Notice to lessees and operators of federal oil and gas leases in the outer continental 

shelf, Gulf of Mexico OCS region, Deepwater benthic communities: U. S. Department of the Interior, Minerals Management 

Service, Gulf of Mexico, NTL 2009-G40. Effective Date January 27, 2010.

FOR PUBLIC RELEASE
10615 Shadow Wood Drive, Suite 200 

Houston, Texas 77043

713.468.1410[o] 713.468.1438 [f] 

www.gemsinc.com 

February 06, 2012 Project No. 0911-1995 

Hess Corporation 

1501 McKinney Street 

Houston, TX 77010

Attention: Mr. Mark Romanchock 

Site Clearance Letter 

Proposed Wellsite LL5 

Block 386 (OCS-G-10350) 

Garden Banks Area 

Gulf of Mexico 

Hess Corporation (Hess) contracted Geoscience Earth & Marine Services, Inc.®, (GEMS) to prepare a 

Site Clearance Letter for the Proposed Wellsite LL5 in Block 386 (OCS G-10350), Garden Banks (GB) 

area. This letter addresses specific seafloor and subsurface geologic conditions around the proposed 

location. The Proposed Wellsite LL5 constitutes the newest phase of development of the Llano field and 

lies within 2,170 ft to 10,121 ft of current Llano infrastructure.

The surface location of the LL5 wellsite lies in the southwestern portion of GB 386. Hess provided the 

following coordinates: 

Proposed Wellsite LL5

Spheroid & Datum: Clarke 1866, NAD27

Projection: UTM Zone 15 North Line Reference Block Calls

X: 1,873,012.68 ft Latitude: 27o 35’ 19.07699” N Inline 3819 3,893 ft FWL

Y: 10,012,021.94 ft Longitude: 92o 16’ 54.06345” W Crossline 4564 1,142 ft FSL

Hess plans to drill this well using a dynamically positioned semisubmersible rig. This assessment 

addresses the seafloor conditions within a 2,000-ft radius around the proposed wellsite location. 

Numerous reports describing the geologic and geotechnical conditions within and surrounding the 

GB 385 and 386 area were produced between August, 1998 and June, 2003 (C&C Technologies, 2003; 

Fugro Geoservices, 1998a, 1998b, 1999, and 2000; GEMS, 2002). These reports were used as the basis 

for Shell Gulf of Mexico Inc.’s, Supplemental Development Operations Coordination Document (DOCD) 

plan to clear proposed wells LL3 and LL4, submitted July 22, 2009. Due to the age of the reports, a new 

assessment of the area using improved seismic data was initiated by Hess to provide an updated 

geological prognosis for the clearance of a revised LL3 location, submitted in December 2009 (GEMS, 

2009). This current assessment is intended to supplement the existing geohazard reports with additional 

details pertaining directly to the seafloor and subsurface conditions surrounding the LL5 well location. 

This assessment also includes a review of the recently acquired high-resolution geophysical data 

collected by an AUV (Autonomous Underwater Vehicle). The data consist of multibeam echosounder, 

side-scan sonar, and subbottom profiler. 

Attachments 

The page-size maps and figures accompanying this letter have been extracted from the seismic 3-D 

volume and high-resolution AUV data supplied by Hess for the geohazard site assessment. These 

illustrations are centered on the LL5 location. 

Map No. GB386-LL5-1: Bathymetry Map 

FOR PUBLIC RELEASE
LL5 Site Clearance Letter 

Hess Corporation // February 06, 2012

Geoscience Earth & Marine Services, Inc. ® // 2 

FORUM ENERGY TECHNOLOGIES, INC. 

 Map No. GB386-LL5-2: Seafloor Rendering 

Map No. GB386-LL5-3: Side-Scan Sonar Mosaic 

Map No. GB386-LL5-4: Side-Scan Sonar Mosaic-Interpreted 

Map No. GB386-LL5-5: Geologic Features Map 

Figure GB386-LL5-1: Power Spectrum Analysis Curve, Proposed Wellsite LL5 (embedded) 

Figure GB386-LL5-2: Unidentified Side-Scan Sonar Contact Number 1 (embedded) 

Figure GB386-LL5-3: Unidentified Side-Scan Sonar Contact Number 2 (embedded) 

Figure GB386-LL5-4: Unidentified Side-Scan Sonar Contact Number 3 (embedded) 

Figure GB386-LL5-5: Side-Scan Sonar Mosaic Showing Drag Scars and Associated 

 Depressions (embedded) 

Figure GB386-LL5-6: Subbottom Profiler Line 124 Illustrating Disturbed Seafloor Caused by 

 Previous Exploration Activity 

Figure GB386-LL5-7: Subbottom Profiler Line 126 Illustrating the Shallow Stratigraphic 

 Conditions at the Proposed LL5 Location 

Figure GB386-LL5-8: Portions of Inline 3819 and Crossline 4564 Showing Conditions Beneath 

 Proposed Wellsite LL5 

Figure GB386-LL5-9: Tophole Prognosis Chart, Proposed Wellsite LL5, Garden Banks, 

 Block 386

Figure GB386-LL5-10: Vertical Profile Showing Stratigraphic Conditions Between Existing Wells 

 and the Proposed LL5 Location 

NTL Requirements

The following letter complies with the Bureau of Ocean Energy Management (BOEM) Notice to Lessees 

(NTL’s) 2008-G04, 2008-G05, and 2009-G40, (MMS, 2008a, b and 2010). The Federal lease block 

GB 386 is not considered archaeologically significant (BOEM, 2011); therefore, requirements set forth in 

NTL 2005-G07 are not applicable (MMS, 2005). However, pursuant to the recently released “Pre-Seabed 

Disturbance Survey Mitigation” issued by BOEM, an archaeological assessment of the data must be 

performed prior to any bottom-disturbing activities. 

Power Spectrum. According to NTL 2008-G05 (MMS, 2008a), 3-D seismic reflection data may be used 

for shallow hazard assessments with approval from the BOEM, Gulf of Mexico Region. A power 

spectrum analysis was conducted from the 3-D seismic data cube provided by Hess to illustrate the data 

parameters. The power spectrum curve was generated within 500-ft radius of the intersection of the 

inline and crossline at the proposed wellsite (Figure GB386-LL5-1). We converted the amplitude vs. 

frequency spectrum, generated by the SMT software, to power vs. frequency by squaring the amplitude 

values as described by J. A. Coffeen, 1978. 

 

Figure GB386-LL5-1: 

Power Spectrum 

Analysis Curve, 

Proposed Wellsite LL5

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

0 10 20 30 40 50 60 70 80 90 100 110 120 Amplitude

Frequency (Hz)

POWER SPECTRUM

FOR PUBLIC RELEASE
LL5 Site Clearance Letter 

Hess Corporation // February 06, 2012

Geoscience Earth & Marine Services, Inc. ® // 3 

FORUM ENERGY TECHNOLOGIES, INC. 

Man-Made Features

The Proposed Wellsite LL5 is planned for the Llano field in GB 386. Several wells have previously been 

drilled near the planned LL5 location in both GB 385 and 386. Table 1 provides a summary of the 

exploration wells drilled within three miles of the proposed LL5 well:

Table 1: Existing Wells Near Proposed Location 

Surface Area/ 

Block Well Name Operator Well Status Distance/Direction From Proposed LL5

GB 386 1 Shell Gulf of Mexico, Inc. Temporarily 

Abandoned 2,170 ft/W

GB 386 2 Shell Gulf of Mexico, Inc. Temporarily 

Abandoned 5,530 ft/ENE

GB 385 LL003 Shell Gulf of Mexico, Inc. Completed 6,600 ft/NW

GB 385 LL001 Shell Gulf of Mexico, Inc. Completed 6,791 ft/NW

GB 385 LL002 Shell Gulf of Mexico, Inc. Completed 10,121 ft/NW

 *Note: Latest infrastructure update from the Bureau of Ocean Energy Management (BOEM) database on 

January, 2012 (BOEM, 2012). 

Shell’s Auger TLP serves as the processing platform for the Llano field. Several existing pipelines trend 

generally southwest from existing Llano wells in GB 385 to the Auger platform in GB 426. Two Shell 8-

inch oil pipelines, one originating from a manifold near the LL1 and LL3 wells and the other from a 

manifold near the LL2 well, trend southwest to GB 426. Shell’s 5-inch umbilical generally trends 

northeastward from the Auger platform to near the existing LL1 and LL3 locations. Two in-field pipelines, 

an 8-inch oil and 5-inch umbilical line, lie between the LL1 and LL2 wells. These pipelines lie over

6,600 ft northwest of the proposed LL5 location.

Archaeological Assessment 

Hess contracted GEMS to examine the high-resolution AUV data collected by Fugro GeoServices, Inc. for 

potential archaeological contacts and avoidances at and immediately surrounding the proposed LL5 well 

location. Unidentified sonar contacts delineated near the proposed location are interpreted to be modern 

debris from nearby lease activity. 

Available Data. High-resolution multibeam bathymetry, subbottom profiler, and side-scan sonar data 

were collected by Fugro for Noble from September 26 – October 14, 2011. Hess provided the side-scan 

sonar, subbottom profiler, and multibeam digital data sets to GEMS for interpretation and reporting 

purposes. 

The AUV survey lines consisted of 120 kHz side-scan sonar data, 2-12 kHz Chirp subbottom data, and 

3m-bin multibeam bathymetry data. The primary AUV lines were spaced at 200 meters providing 100% 

overlap or 200% coverage on all primary lines. The AUV tie lines were spaced at 900 meters. Thirteen 

(13) high-resolution AUV side-scan sonar lines were reviewed for this assessment. The reviewed lines 

pass within 50-900 meters of the proposed LL5 location. Lines 124-131, 211-212, and 400-402 were 

reviewed for potential cultural resources. 

The digital data for the Llano Prospect proposed LL5 well was examined for archaeological contacts 

using Chesapeake Technologies’ SonarWiz 5 software. Targets were identified and mapped in SonarWiz 

before being exported to MapInfo and then to AutoCAD for incorporation on the Archaeological 

Assessment Map. The side-scan sonar mosaic and bathymetric contours were generated from the Fugro 

survey data. No potential cultural resources were delineated within 2,500 ft of the proposed well location. 

Three unidentified side-scan sonar contacts were delineated in the data within 3,210 ft from the proposed 

well location.

FOR PUBLIC RELEASE
LL5 Site Clearance Letter 

Hess Corporation // February 06, 2012

Geoscience Earth & Marine Services, Inc. ® // 4 

FORUM ENERGY TECHNOLOGIES, INC. 

Archaeological Avoidance. No archaeological avoidances exist within the area of potential effect for 

the proposed GB 386 LL5 well. No known shipwrecks lie within the area of potential effect.

Proposed Well LL5. The proposed LL5 well is located in the southwestern corner of Garden Banks 

Block 386, 2,634 ft below Mean Sea Level (MSL). Three unidentified side-scan sonar contacts were 

delineated within 3,210 ft of the proposed well location (Table 2 and Figures GB386-LL5-2 through 

GB386-LL5-4). 

Table 2: Unidentified Side-Scan Sonar Contacts Located Within 3,210 ft of the Proposed Well 

Number Area/ 

Block Description Length (ft)

Width 

(ft)

Height 

(ft) X (ft) Y (ft)

1 GB 386 Linear 21.98 9.84 0.00 1,869,954.00 10,011,389.28

2 GB 386 Circular 30.51 26.25 0.00 1,872,017.81 10,014,375.80

3 GB 430 Linear 12.13 4.26 0.00 1,875,440.51 10,010,640.17

Unidentified Side-Scan Sonar Contact Number 1 is a linear contact measuring approximately 22 ft long, 

10 ft wide, and displays no measurable height (Figure GB386-LL5-2). The contact is interpreted to 

represent debris from the nearby Shell #1 well. This contact is not recommended for archaeological 

avoidance or investigation. 

Figure GB386-LL5-2: Unidentified Side-Scan Sonar Contact Number 1 

Unidentified Side-Scan Sonar Contact Number 2 is a circular contact measuring approximately 30 ft long, 

and 26 ft wide (Figure GB386-LL5-3). The contact is interpreted to represent seafloor debris from the 

nearby well. This contact is not recommended for archaeological avoidance or investigation. 

FOR PUBLIC RELEASE
LL5 Site Clearance Letter 

Hess Corporation // February 06, 2012

Geoscience Earth & Marine Services, Inc. ® // 5 

FORUM ENERGY TECHNOLOGIES, INC. 

Figure GB386-LL5-3: Unidentified Side-Scan Sonar Contact Number 2 

Unidentified Side-Scan Sonar Contact Number 3 is a linear contact measuring approximately 12 ft long, 

and 4 ft wide (Figure GB386-LL5-4). The contact is interpreted to represent seafloor debris. This contact 

is not recommended for archaeological avoidance or investigation. 

Figure GB386-LL5-4: Unidentified Side-Scan Sonar Contact Number 3 

Several areas of drag scars consisting of shallow depressions and low mounds were imaged in the sidescan sonar data and can be seen on the sonar mosaic as darker returns. None of these areas represent 

side-scan sonar contacts. Each area was examined in the side-scan sonar and multibeam bathymetry 

before being eliminated as a possible side-scan sonar contact. The drag scars are in proximity to the 

previously drilled Shell well and likely represent previous anchoring activities (Figure GB386-LL5-5).

FOR PUBLIC RELEASE
LL5 Site Clearance Letter 

Hess Corporation // February 06, 2012

Geoscience Earth & Marine Services, Inc. ® // 6 

FORUM ENERGY TECHNOLOGIES, INC. 

Figure GB386-LL5-5: Side-Scan Sonar Mosaic Showing Drag Scars and Associated Depressions 

No potential cultural resources are identified within the reviewed data surrounding the proposed LL5 well 

location in GB 386. 

Findings. Based on the available high-resolution geophysical data no potential submerged cultural 

resources were delineated in the area of potential effect. No unidentified side-scan sonar contacts were 

delineated in this data review within 3,210 ft of the proposed LL5 well.

Wellsite Conditions 

The surface location is clear of any geologic constraining conditions within a 2,000 ft radius of the 

proposed wellsite. 

Water Depth and Seafloor Conditions. Seafloor conditions are favorable at the proposed wellsite 

location. The water depth at the proposed surface location is approximately -2,634 ft and the seafloor 

slopes to the south-southwest at about 3.8° (Map GB386-LL5-1). The Proposed Wellsite LL5 lies along 

the base of a shallow salt topographic high (Map GB386-LL5-2). Seafloor conditions at the proposed 

location appear to be relatively smooth. Subtle gullies and lobate features highlighted on the seafloor 

rendering are likely associated with buried debris flow events originating from the topographic high to the 

north. A surficial drape of normally consolidated soft clays likely covers the seafloor at the location. 

Several areas of disturbed seafloor (shallow depressions and mounds) are located within 2,000 ft of the 

proposed LL5 location (Figure GB386-LL5-6). The closest area of disturbed seafloor to the proposed 

surface location is approximately 340 ft to the northeast (Maps GB386-LL5-3 and GB386-LL5-4). These 

areas are not related to hydrocarbon seepage and are likely associated with previous anchoring activities 

from nearby wells (Figure GB386-LL5-6). 

Deepwater Benthic Communities. Even though GB 386 is a designated chemosynthetic block, there 

are no features or areas that could support significant deepwater benthic communities within 2,000 ft of 

the proposed location (Maps GB386-LL5-3 and GB386-LL5-4), MMS, 2010. The possible hydrocarbon

Shell #1 Well

Drag Scars and Depressions

GB 385 GB 386

GB 429 GB 430

N

FOR PUBLIC RELEASE
LL5 Site Clearance Letter 

Hess Corporation // February 06, 2012

Geoscience Earth & Marine Services, Inc. ® // 7 

FORUM ENERGY TECHNOLOGIES, INC. 

seep related areas (characterized by high-amplitude returns and/or rough seabed texture) occur more 

than 2,000 ft northeast of the proposed LL5 well location (Maps GB386-LL5-3 and GB386-LL5-4). 

Stratigraphy. Stratigraphic conditions are shown on Figures GB386-LL5-7 through GB386-LL5-9. The 

seafloor and near surface sediments at the Proposed Wellsite LL5 are expected to be a pelagic clay 

drape overlying hemipelagic clays and silty clays interbedded with thin, clay-prone mass-transport 

deposits (Figure GB386-LL5-7). Some of the shallow mass-transport deposits may be associated with 

failure events from the adjacent topographic high. 

In general, the sediments below the seafloor to the limit of investigation (5,636 ft bml or 8,269 ft bsl)

consist primarily of hemipelagic clays and mud-dominated turbidite deposits. Interbedded in places within 

the generally stratified section are discontinuous units of clay-prone mass-transport deposits. Well logs 

from the existing LL1 and LL2 wells illustrate a clay-dominated shallow section (Figure GB386-LL5-10);

however, occasional thin silt or sand seams may be encountered below 1,409 ft bml to the limit of 

investigation (5,636 ft bml) at the proposed site. 

Faults. No seafloor or buried faults will be penetrated by the Proposed Wellsite LL5 in the shallow 

section to the limit of investigation (Figures GB386-LL5-7 through GB386-LL5-9). A series of faults are 

evident on the seafloor rendering and subbottom profiler lines north and northeast of the proposed 

surface location (Map GB386-LL5-2). The closest of these faults to the proposed location is 

approximately 1,340 ft to the northeast. The faults appear to be draped by approximately 10 to 25 ft of 

sediment and are downthrown to the east, away from a vertical borehole at the LL5 location. 

Shallow Gas and Shallow Water Flow. Significant shallow gas is not expected at this proposed 

wellsite (Figures GB386-LL5-8 and GB386-LL5-9). The potential for shallow water flow at this well 

location is negligible to low. 

 Shallow Gas. There are no apparent subsurface high-amplitude anomalies directly below the 

proposed wellsite (Map GB386-LL5-5). The potential for encountering shallow gas is considered 

negligible in the clay-prone unit between the seafloor and 1,409 ft bml. There is a low potential for 

encountering minor amounts of biogenic gas within thin coarse-grained layers between 1,409 ft to the 

limit of investigation (5,636 ft bml). 

Shallow Water Flow. The potential for shallow water flow at this well location is negligible to low 

(Figure GB386-LL5-9). The five Llano exploration wells across GB 385 and 386 (approximately 2,170 ft 

to 10,121 ft from the proposed location), did not report water flow conditions during drilling operations. 

Generally, similar stratigraphic units are expected to be penetrated at the proposed LL5 location (Figure 

GB386-LL5-10). A section of thin sands may be encountered within mass-transport deposits between 

1,409 ft and 1,788 ft bml at the proposed location (Figure GB386-LL5-9). However, these possible sands 

are not likely to produce sustained flow. The shallow water flow potential for this unit is considered low. 

The remaining, generally clay-rich section has a negligible potential for overpressured sands. 

Closing 

The Proposed Wellsite LL5, Garden Banks Block 386, appears suitable for exploration drilling operations. 

No major hazards or constraints are defined by the 3-D or high-resolution AUV data at the proposed 

location. 

Additionally, no potential submerged cultural resources exist within 3,210 ft of the proposed LL5 location. 

Should any potentially historic materials such as textiles, wood, ceramics, or other items be uncovered 

during operations in the area, all operations must cease and BOEM be notified within 48 hours. 

 

FOR PUBLIC RELEASE
FOR PUBLIC RELEASE
LL5 Site Clearance Letter 

Hess Corporation // February 06, 2012

Geoscience Earth & Marine Services, Inc. ® // 9 

FORUM ENERGY TECHNOLOGIES, INC. 

Minerals Management Service, 2008b, Notice to lessees and operators of federal oil, gas, and sulphur leases and pipeline 

right-of-way holders in the outer continental shelf, Gulf of Mexico OCS region, shallow hazards program: U. S. Department 

of the Interior, Minerals Management Service, Gulf of Mexico, NTL 2008-G05. Effective Date May 1, 2008. 

Minerals Management Service, 2010, Notice to lessees and operators of federal oil and gas leases in the outer continental 

shelf, Gulf of Mexico OCS region, Deepwater benthic communities: U. S. Department of the Interior, Minerals Management 

Service, Gulf of Mexico, NTL 2009-G40. Effective Date January 27, 2010.

FOR PUBLIC RELEASE
10615 Shadow Wood Drive, Suite 200 

Houston, Texas 77043

713.468.1410[o] 713.468.1438 [f] 

www.gemsinc.com 

February 06, 2012 Project No. 0911-1995 

Hess Corporation 

1501 McKinney Street 

Houston, TX 77010

Attention: Mr. Mark Romanchock 

Site Clearance Letter 

Proposed Wellsite LL6 

Block 386 (OCS-G-10350) 

Garden Banks Area 

Gulf of Mexico 

Hess Corporation (Hess) contracted Geoscience Earth & Marine Services, Inc.®, (GEMS) to prepare a 

Site Clearance Letter for the Proposed Wellsite LL6 in Block 386 (OCS G-10350), Garden Banks (GB) 

area. This letter addresses specific seafloor and subsurface geologic conditions around the proposed 

location. The Proposed Wellsite LL6 constitutes the newest phase of development of the Llano field and 

lies within 2,215 ft to 10,145 ft of current Llano infrastructure.

The surface location of the LL6 wellsite lies in the southwestern portion of GB 386. Hess provided the 

following coordinates: 

Proposed Wellsite LL6

Spheroid & Datum: Clarke 1866, NAD27

Projection: UTM Zone 15 North Line Reference Block Calls

X: 1,873,060.57 ft Latitude: 27o 35’ 19.59052” N Inline 3820 3,941 ft FWL

Y: 10,012,074.06 ft Longitude: 92o 16’ 53.52769” W Crossline 4564 1,194 ft FSL

Hess plans to drill this well using a dynamically positioned semisubmersible rig. This assessment 

addresses the seafloor conditions within a 2,000-ft radius around the proposed wellsite location. 

Numerous reports describing the geologic and geotechnical conditions within and surrounding the 

GB 385 and 386 area were produced between August, 1998 and June, 2003 (C&C Technologies, 2003; 

Fugro Geoservices, 1998a, 1998b, 1999, and 2000; GEMS, 2002). These reports were used as the basis 

for Shell Gulf of Mexico Inc.’s, Supplemental Development Operations Coordination Document (DOCD) 

plan to clear proposed wells LL3 and LL4, submitted July 22, 2009. Due to the age of the reports, a new 

assessment of the area using improved seismic data was initiated by Hess to provide an updated 

geological prognosis for the clearance of a revised LL3 location, submitted in December 2009 (GEMS, 

2009). This current assessment is intended to supplement the existing geohazard reports with additional 

details pertaining directly to the seafloor and subsurface conditions surrounding the LL6 well location. 

This assessment also includes a review of the recently acquired high-resolution geophysical data 

collected by an AUV (Autonomous Underwater Vehicle). The data consist of multibeam echosounder, 

side-scan sonar, and subbottom profiler. 

Attachments 

The page-size maps and figures accompanying this letter have been extracted from the seismic 3-D 

volume and high-resolution AUV data supplied by Hess for the geohazard site assessment. These 

illustrations are centered on the LL6 location. 

Map No. GB386-LL6-1: Bathymetry Map 

FOR PUBLIC RELEASE
LL6 Site Clearance Letter 

Hess Corporation // February 06, 2012

Geoscience Earth & Marine Services, Inc. ® // 2 

FORUM ENERGY TECHNOLOGIES, INC. 

 Map No. GB386-LL6-2: Seafloor Rendering 

Map No. GB386-LL6-3: Side-Scan Sonar Mosaic 

Map No. GB386-LL6-4: Side-Scan Sonar Mosaic-Interpreted 

Map No. GB386-LL6-5: Geologic Features Map 

Figure GB386-LL6-1: Power Spectrum Analysis Curve, Proposed Wellsite LL6 (embedded) 

Figure GB386-LL6-2: Unidentified Side-Scan Sonar Contact Number 1 (embedded) 

Figure GB386-LL6-3: Unidentified Side-Scan Sonar Contact Number 2 (embedded) 

Figure GB386-LL6-4: Unidentified Side-Scan Sonar Contact Number 3 (embedded) 

Figure GB386-LL6-5: Side-Scan Sonar Mosaic Showing Drag Scars and Associated 

 Depressions (embedded) 

Figure GB386-LL6-6: Subbottom Profiler Line 124 Illustrating Disturbed Seafloor Caused by 

 Previous Exploration Activity 

Figure GB386-LL6-7: Subbottom Profiler Line 126 Illustrating the Shallow Stratigraphic 

 Conditions at the Proposed LL6 Location 

Figure GB386-LL6-8: Portions of Inline 3820 and Crossline 4564 Showing Conditions Beneath 

 Proposed Wellsite LL6 

Figure GB386-LL6-9: Tophole Prognosis Chart, Proposed Wellsite LL6, Garden Banks, 

 Block 386

Figure GB386-LL6-10: Vertical Profile Showing Stratigraphic Conditions Between Existing Wells 

 and the Proposed LL6 Location 

NTL Requirements

The following letter complies with the Bureau of Ocean Energy Management (BOEM) Notice to Lessees 

(NTL’s) 2008-G04, 2008-G05, and 2009-G40, (MMS, 2008a,b and 2010). The Federal lease block 

GB 386 is not considered archaeologically significant (BOEM, 2011); therefore, requirements set forth in 

NTL 2005-G07 are not applicable (MMS, 2005). However, pursuant to the recently released “Pre-Seabed 

Disturbance Survey Mitigation” issued by BOEM, an archaeological assessment of the data must be 

performed prior to any bottom-disturbing activities. 

Power Spectrum. According to NTL 2008-G05 (MMS, 2008a), 3-D seismic reflection data may be used 

for shallow hazard assessments with approval from the BOEM, Gulf of Mexico Region. A power 

spectrum analysis was conducted from the 3-D seismic data cube provided by Hess to illustrate the data 

parameters. The power spectrum curve was generated within 500-ft radius of the intersection of the 

inline and crossline at the proposed wellsite (Figure GB386-LL6-1). We converted the amplitude vs. 

frequency spectrum, generated by the SMT software, to power vs. frequency by squaring the amplitude 

values as described by J. A. Coffeen, 1978. 

 

Figure GB386-LL6-1: 

Power Spectrum 

Analysis Curve, 

Proposed Wellsite LL6

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

0 10 20 30 40 50 60 70 80 90 100 110 120

Amplitude

Frequency (Hz)

POWER SPECTRUM

FOR PUBLIC RELEASE
LL6 Site Clearance Letter 

Hess Corporation // February 06, 2012

Geoscience Earth & Marine Services, Inc. ® // 3 

FORUM ENERGY TECHNOLOGIES, INC. 

Man-Made Features

The Proposed Wellsite LL6 is planned for the Llano field in GB 386. Several wells have previously been 

drilled near the planned LL6 location in both GB 385 and 386. Table 1 provides a summary of the 

exploration wells drilled within three miles of the proposed LL6 well:

Table 1: Existing Wells Near Proposed Location 

Surface Area/ 

Block Well Name Operator Well Status Distance/Direction From Proposed LL6

GB 386 1 Shell Gulf of Mexico, Inc. Temporarily 

Abandoned 2,215 ft/W

GB 386 2 Shell Gulf of Mexico, Inc. Temporarily 

Abandoned 5,470 ft/ENE

GB 385 LL003 Shell Gulf of Mexico, Inc. Completed 6,612 ft/NW

GB 385 LL001 Shell Gulf of Mexico, Inc. Completed 6,795 ft/NW

GB 385 LL002 Shell Gulf of Mexico, Inc. Completed 10,145 ft/NW

 *Note: Latest infrastructure update from the Bureau of Ocean Energy Management (BOEM) database on 

January, 2012 (BOEM, 2012). 

Shell’s Auger TLP serves as the processing platform for the Llano field. Several existing pipelines trend 

generally southwest from existing Llano wells in GB 385 to the Auger platform in GB 426. Two Shell 8-

inch oil pipelines, one originating from a manifold near the LL1 and LL3 wells and the other from a 

manifold near the LL2 well, trend southwest to GB 426. Shell’s 5-inch umbilical generally trends 

northeastward from the Auger platform to near the existing LL1 and LL3 locations. Two in-field pipelines, 

an 8-inch oil and 5-inch umbilical line, lie between the LL1 and LL2 wells. These pipelines lie over

6,612 ft northwest of the proposed LL6 location.

Archaeological Assessment 

Hess contracted GEMS to examine the high-resolution AUV data collected by Fugro GeoServices, Inc. for 

potential archaeological contacts and avoidances at and immediately surrounding the proposed LL6 well 

location. Unidentified sonar contacts delineated near the proposed location are interpreted to be modern 

debris from nearby lease activity. 

Available Data. High-resolution multibeam bathymetry, subbottom profiler, and side-scan sonar data 

were collected by Fugro for Noble from September 26 – October 14, 2011. Hess provided the side-scan 

sonar, subbottom profiler, and multibeam digital data sets to GEMS for interpretation and reporting 

purposes. 

The AUV survey lines consisted of 120 kHz side-scan sonar data, 2-12 kHz Chirp subbottom data, and 

3m-bin multibeam bathymetry data. The primary AUV lines were spaced at 200 meters providing 100% 

overlap or 200% coverage on all primary lines. The AUV tie lines were spaced at 900 meters. Thirteen 

(13) high-resolution AUV side-scan sonar lines were reviewed for this assessment. The reviewed lines 

pass within 50-900 meters of the proposed LL6 location. Lines 124-131, 211-212, and 400-402 were 

reviewed for potential cultural resources. 

The digital data for the Llano Prospect proposed LL6 well was examined for archaeological contacts 

using Chesapeake Technologies’ SonarWiz 5 software. Targets were identified and mapped in SonarWiz 

before being exported to MapInfo and then to AutoCAD for incorporation on the Archaeological 

Assessment Map. The side-scan sonar mosaic and bathymetric contours were generated from the Fugro 

survey data. Three unidentified side-scan sonar contacts were delineated in the data within 3,280 ft from 

the proposed well location. Sonar Contact Number 2 is approximately 2,500 ft from the proposed well; 

however, no potential cultural resources are delineated within the 2,500 ft radius (Figures GB386-LL6-4 

and GB386-LL6-5). 

FOR PUBLIC RELEASE
LL6 Site Clearance Letter 

Hess Corporation // February 06, 2012

Geoscience Earth & Marine Services, Inc. ® // 4 

FORUM ENERGY TECHNOLOGIES, INC. 

Archaeological Avoidance. No archaeological avoidances exist within the area of potential effect for 

the proposed GB 386 LL6 well. No known shipwrecks lie within the area of potential effect.

Proposed Well LL6. The proposed LL6 well is located in the southwestern corner of Garden Banks 

Block 386, 2,629 ft below Mean Sea Level (MSL). Three unidentified side-scan sonar contacts were 

delineated within 3,280 ft of the proposed well location (Table 2 and Figures GB386-LL6-2 through 

GB386-LL6-4). 

Table 2: Unidentified Side-Scan Sonar Contacts Located Within 3,280 ft of the Proposed Well 

Number Area/ 

Block Description Length (ft)

Width 

(ft)

Height 

(ft)

X (ft) Y (ft)

1 GB 386 Linear 21.98 9.84 0.00 1,869,954.00 10,011,389.28

2 GB 386 Circular 30.51 26.25 0.00 1,872,017.81 10,014,375.80

3 GB 430 Linear 12.13 4.26 0.00 1,875,440.51 10,010,640.17

Unidentified Side-Scan Sonar Contact Number 1 is a linear contact measuring approximately 22 ft long, 

10 ft wide, and displays no measurable height (Figure GB386-LL6-2). The contact is interpreted to 

represent debris from the nearby Shell #1 well. This contact is not recommended for archaeological 

avoidance or investigation. 

Figure GB386-LL6-2: Unidentified Side-Scan Sonar Contact Number 1 

Unidentified Side-Scan Sonar Contact Number 2 is a circular contact measuring approximately 30 ft long, 

and 26 ft wide (Figure GB386-LL6-3). The contact is interpreted to represent seafloor debris from the 

nearby well. This contact is not recommended for archaeological avoidance or investigation. 

FOR PUBLIC RELEASE
LL6 Site Clearance Letter 

Hess Corporation // February 06, 2012

Geoscience Earth & Marine Services, Inc. ® // 5 

FORUM ENERGY TECHNOLOGIES, INC. 

Figure GB386-LL6-3: Unidentified Side-Scan Sonar Contact Number 2 

Unidentified Side-Scan Sonar Contact Number 3 is a linear contact measuring approximately 12 ft long, 

and 4 ft wide (Figure GB386-LL6-4). The contact is interpreted to represent seafloor debris. This contact 

is not recommended for archaeological avoidance or investigation. 

Figure GB386-LL6-4: Unidentified Side-Scan Sonar Contact Number 3 

Several areas of drag scars consisting of shallow depressions and low mounds were imaged in the sidescan sonar data and can be seen on the sonar mosaic as darker returns. None of these areas represent 

side-scan sonar contacts. Each area was examined in the side-scan sonar and multibeam bathymetry 

before being eliminated as a possible side-scan sonar contact. The drag scars are in proximity to the 

previously drilled Shell well and likely represent previous anchoring activities (Figure GB386-LL6-5).

FOR PUBLIC RELEASE
LL6 Site Clearance Letter 

Hess Corporation // February 06, 2012

Geoscience Earth & Marine Services, Inc. ® // 6 

FORUM ENERGY TECHNOLOGIES, INC. 

Figure GB386-LL6-5: Side-Scan Sonar Mosaic Showing Drag Scars and Associated Depressions 

No potential cultural resources are identified within the reviewed data surrounding the proposed LL6 well 

location in GB 386. 

Findings. Based on the available high-resolution geophysical data no potential submerged cultural 

resources were delineated in the area of potential effect. No unidentified side-scan sonar contacts were 

delineated in this data review within 3,280 ft of the proposed LL6 well. 

Wellsite Conditions 

The surface location is clear of any geologic constraining conditions within a 2,000 ft radius of the 

proposed wellsite. 

Water Depth and Seafloor Conditions. Seafloor conditions are favorable at the proposed wellsite 

location. The water depth at the proposed surface location is approximately -2,629 ft and the seafloor 

slopes to the south-southwest at about 4.2° (Map GB386-LL6-1). The Proposed Wellsite LL6 lies along 

the base of a shallow salt topographic high (Map GB386-LL6-2). Seafloor conditions at the proposed 

location appear to be relatively smooth. Subtle gullies and lobate features highlighted on the seafloor 

rendering are likely associated with buried debris flow events originating from the topographic high to the 

north. A surficial drape of normally consolidated soft clays likely covers the seafloor at the location. 

Several areas of disturbed seafloor (shallow depressions and mounds) are located within 2,000 ft of the 

proposed LL6 location (Figure GB386-LL6-6). The closest area of disturbed seafloor to the proposed 

surface location is approximately 250 ft to the northeast (Maps GB386-LL6-3 and GB386-LL6-4). These 

areas are not related to hydrocarbon seepage and are likely associated with previous anchoring activities 

from nearby wells (Figure GB386-LL6-6). 

Deepwater Benthic Communities. Even though GB 386 is a designated chemosynthetic block, there 

are no features or areas that could support significant deepwater benthic communities within 2,000 ft of 

the proposed location (Maps GB386-LL6-3 and GB386-LL6-4), MMS, 2010. The possible hydrocarbon

Shell #1 Well

Drag Scars and Depressions

GB 385 GB 386

GB 429 GB 430

N

FOR PUBLIC RELEASE
LL6 Site Clearance Letter 

Hess Corporation // February 06, 2012

Geoscience Earth & Marine Services, Inc. ® // 7 

FORUM ENERGY TECHNOLOGIES, INC. 

seep related areas (characterized by high-amplitude returns and/or rough seabed texture) occur more 

than 2,000 ft northeast of the proposed LL6 well location (Maps GB386-LL6-3 and GB386-LL6-4). 

Stratigraphy. Stratigraphic conditions are shown on Figures GB386-LL6-7 through GB386-LL6-9. The 

seafloor and near surface sediments at the Proposed Wellsite LL6 are expected to be a pelagic clay 

drape overlying hemipelagic clays and silty clays interbedded with thin, clay-prone mass-transport 

deposits (Figure GB386-LL6-7). Some of the shallow mass-transport deposits may be associated with 

failure events from the adjacent topographic high. 

In general, the sediments below the seafloor to the limit of investigation (5,643 ft bml or 8,272 ft bsl)

consist primarily of hemipelagic clays and mud-dominated turbidite deposits. Interbedded in places within 

the generally stratified section are discontinuous units of clay-prone mass-transport deposits. Well logs 

from the existing LL1 and LL2 wells illustrate a clay-dominated shallow section (Figure GB386-LL6-10);

however, occasional thin silt or sand seams may be encountered below 1,400 ft bml to the limit of 

investigation (5,643 ft bml) at the proposed site. 

Faults. No seafloor or buried faults will be penetrated by the Proposed Wellsite LL6 in the shallow 

section to the limit of investigation (Figures GB386-LL6-7 through GB386-LL6-9). A series of faults are 

evident on the seafloor rendering and subbottom profiler lines north and northeast of the proposed 

surface location (Map GB386-LL6-2). The closest of these faults to the proposed location is 

approximately 1,335 ft to the northeast. The faults appear to be draped by approximately 10 to 25 ft of 

sediment and are downthrown to the east, away from a vertical borehole at the LL6 location. 

Shallow Gas and Shallow Water Flow. Significant shallow gas is not expected at this proposed 

wellsite (Figures GB386-LL6-8 and GB386-LL6-9). The potential for shallow water flow at this well 

location is negligible to low. 

 Shallow Gas. There are no apparent subsurface high-amplitude anomalies directly below the 

proposed wellsite (Map GB386-LL6-5). The potential for encountering shallow gas is considered 

negligible in the clay-prone unit between the seafloor and 1,400 ft bml. There is a low potential for 

encountering minor amounts of biogenic gas within thin coarse-grained layers between 1,400 ft to the 

limit of investigation (5,643 ft bml). 

Shallow Water Flow. The potential for shallow water flow at this well location is negligible to low 

(Figure GB386-LL6-9). The five Llano exploration wells across GB 385 and 386 (approximately 2,215 ft 

to 10,145 ft from the proposed location), did not report water flow conditions during drilling operations. 

Generally, similar stratigraphic units are expected to be penetrated at the proposed LL6 location (Figure 

GB386-LL6-10). A section of thin sands may be encountered within mass-transport deposits between 

1,400 ft and 1,781 ft bml at the proposed location (Figure GB386-LL6-9). However, these possible sands 

are not likely to produce sustained flow. The shallow water flow potential for this unit is considered low. 

The remaining, generally clay-rich section has a negligible potential for overpressured sands. 

Closing 

The Proposed Wellsite LL6, Garden Banks Block 386, appears suitable for exploration drilling operations. 

No major hazards or constraints are defined by the 3-D or high-resolution AUV data at the proposed 

location. 

Additionally, no potential submerged cultural resources exist within 3,280 ft of the proposed LL6 location. 

Should any potentially historic materials such as textiles, wood, ceramics, or other items be uncovered 

during operations in the area, all operations must cease and BOEM be notified within 48 hours. 

 

FOR PUBLIC RELEASE
FOR PUBLIC RELEASE
LL6 Site Clearance Letter 

Hess Corporation // February 06, 2012

Geoscience Earth & Marine Services, Inc. ® // 9 

FORUM ENERGY TECHNOLOGIES, INC. 

Minerals Management Service, 2008b, Notice to lessees and operators of federal oil, gas, and sulphur leases and pipeline 

right-of-way holders in the outer continental shelf, Gulf of Mexico OCS region, shallow hazards program: U. S. Department 

of the Interior, Minerals Management Service, Gulf of Mexico, NTL 2008-G05. Effective Date May 1, 2008. 

Minerals Management Service, 2010, Notice to lessees and operators of federal oil and gas leases in the outer continental 

shelf, Gulf of Mexico OCS region, Deepwater benthic communities: U. S. Department of the Interior, Minerals Management 

Service, Gulf of Mexico, NTL 2009-G40. Effective Date January 27, 2010.

FOR PUBLIC RELEASE
Hess Corporation    Llano Field  

Supplemental EP    Garden Banks Block 386, OCS‐G10350

Appendix D

Hydrogen Sulfide (H2S) Information

(a) Concentration

Hess does not anticipate encountering H2S while conducting the operations proposed under this

plan.

(b) Classification

[PROPRIETARY INFORMATION OMITTED]

Therefore, in accordance with Title 30 CFR parts 250.490(c) and 550.215, Hess Corporation

requests that Garden Banks Block 386 be classified by the Bureau of Ocean Energy Management

(BOEM) as H2S Absent.  

(c) H2S Contingency Plan

In accordance with the Title 30 CFR Part 250.490(f), should BOEM determine the locations

proposed under this plan to be either H2S known or unknown, Hess Corporation will submit an

H2S Contingency Plan for review and approval prior to the initiation of operations.

(d) Modeling Report

Hess Corporation does not anticipate to encounter or to handle H2S at concentrations of greater

than 500 ppm, therefore this section of the plan is not applicable.

FOR PUBLIC RELEASE
Hess Corporation    Llano Field  

Supplemental EP    Garden Banks Block 386, OCS‐G10350

Appendix E

Mineral Resource Conservation Information

No development or production is proposed under this plan; this section is required only for

DOCDs.

FOR PUBLIC RELEASE
Hess Corporation    Llano Field  

Supplemental EP    Garden Banks Block 386, OCS‐G10350

Appendix F

Biological, Physical and Socioeconomic Information

  

(a) High‐Density Deepwater Benthic Communities Information

BOEM/BSEE require site‐specific surveys of bottom disturbing actions in water depths greater

than 300 meters in order to evaluate the potential for the region to support high‐density

deepwater benthic communities.    These areas are subsequently protected from physical

disturbances associated with muds/cuttings discharge locations, anchors, pipelines, chains and

templates.

Water depths in Garden Banks Block 386 range from 1,980 – 2,840 feet.    Seafloor disturbing

activities proposed while drilling under this Exploration Plan are discussed within Appendix C:  

Geological and Geophysical Information and are addressed within the Wellsite Clearance Letters

prepared by Geoscience Earth & Marine Services, Inc., included as Attachments C‐5.  Within this

report, specific seafloor and subsurface geologic conditions within a 2,000’ radius around the

proposed surface locations are discussed in detail and ensure that there will be no disturbances

to high‐density deepwater benthic communities within that area.

● Features or areas that could support high‐density deepwater benthic communities are not

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

● No anchors will be utilized under this plan, therefore, features or areas that could support

high‐density chemosynthetic communities are not located within 250 feet of any seafloor

disturbances resulting from the use of anchors (including those caused by anchors, anchor

chains and wire ropes).    

(b) Topographic Features Map

There are no topographic lease stipulations associated with Garden Banks Block 386, therefore

the activities proposed under this plan should not have an effect on topographic features and

the map described in Attachment 2, Section A, Item No. 1 of NTL No. 2009‐G39, “Biologically‐

Sensitive Underwater Features and Areas” is not required to be included as part of this plan.

(c) Topographic Features Statement (Shunting)

The bottom‐disturbing activities proposed under this plan are not located within 500‐feet of the

designated “No Activity Zone” of a topographic feature, nor are the surface locations of the

proposed wells located within 3‐miles of any identified topographic feature; therefore Hess is

not required to shunt drill cuttings and/or drilling fluids.    The information described in

Attachment 2, Section A, Item No. 2 of NTL No. 2009‐G39, “Biologically‐Sensitive Underwater

Features and Areas” is not required to be included as part of this plan.   

FOR PUBLIC RELEASE
Hess Corporation    Llano Field  

Supplemental EP    Garden Banks Block 386, OCS‐G10350

(d) Live Bottoms (Pinnacle Trend) Map

Garden Banks Block 386 is not one of the seventy‐four blocks associated with Live Bottoms

(Pinnacle Trend) lease stipulations as identified in NTL 2009‐G39, nor are there any bottom‐

disturbing activities proposed within 100 feet of any hard bottoms/pinnacles having a vertical

relief of 8‐feet or more, therefore the Live Bottom (Pinnacle Trend) Map described in

Attachment 4, Section A of NTL No. 2009‐G39, “Biologically‐Sensitive Underwater Features and

Areas” is not required to be included as part of this plan.

(e) Live Bottoms (Low Relief) Map

Garden Banks Block 386 is over 250 miles from the nearest block associated with the Live

Bottom (Low Relief) Lease Stipulation, therefore the activities proposed under this plan are

believed to have no effect on live bottom (low relief features) and the Live Bottom (Low Relief)

Map is described in Attachment 6, Section A of NTL No. 2009‐G39, “Biologically‐Sensitive

Underwater Features and Areas” is not required to be included as part of this plan.

(f) Potentially Sensitive Biologic Features

Garden Banks Block 386 is located approximately 20 miles south of the nearest identified

potentially sensitive biological topographic features (Rezak‐Sidner Bank) and is not associated

with any of the live bottom (pinnacle trend) stipulated blocks in Attachment 3 of NTL No. 2009‐

G39, therefore the activities proposed under this plan should have no effect on potentially

sensitive biological features and the map described in Attachment 8, Section A of NTL No. 2009‐

G39, “Biologically‐Sensitive Underwater Features and Areas” is not required to be included as

part of this plan.   

(g) Remotely Operated Vehicle (ROV) Monitoring Survey Plan

Garden Banks Block 386 is located within Grid Number 6 as depicted on the “Grid EA and ROV

Survey Status Report,” dated February 10, 2010, located within NTL 2008‐G06, “Remotely

Operated Vehicle Surveys in Deepwater.”   Adequate ROV survey coverage exists for this area

and as per NTL 2008‐G06, this information is not required to be included as part of this plan.

FOR PUBLIC RELEASE
Hess Corporation    Llano Field  

Supplemental EP    Garden Banks Block 386, OCS‐G10350

(h) Threatened or Endangered Species, Critical Habitat and Marine Mammal Information

Federally‐listed endangered or threatened species designated under the Endangered Species

Act that may occur in the Gulf of Mexico are listed below.  Of the 28 different species of marine

mammals known to occur in the Gulf of Mexico, all are protected under the Marine Mammal

Protection Act and 6 species are considered endangered.  

Garden Banks 386 is not designated as a critical habitat for any of these species.    Hess

Corporation does not anticipate that any threatened or endangered species will be adversely

affected as a result of proposed activities under this Supplemental Exploration Plan.  

(i) Archaeological Report

Recent mitigation guidelines released under the BOEMRE entitled, “Pre‐Seabed Disturbance

Survey Mitigation” provide that BOEM may require as a condition of approval, an archaeological

assessment to be performed over the area of potential effect (APE) prior to commencing any

bottom‐disturbing activities.   

In November 2011, Fugro Geoservices, Inc. conducted a high‐resolution geophysical survey over

the Llano field, Blocks 340, 341, 342, 343, 384, 385, 386, 387, 428, 429, 430 and 431.    The

findings of the archaeological assessment report (Report No. 2411‐5009) associated with the

survey determined that of the 56 sonar contacts identified, none were interpreted as

FOR PUBLIC RELEASE
Hess Corporation    Llano Field  

Supplemental EP    Garden Banks Block 386, OCS‐G10350

archaeologically significant.    This report was submitted to BOEM by Shell Gulf of Mexico, Inc.

under separate cover.

Prior to performing any bottom‐disturbing activities, Hess will submit to BOEM, certification

from a professional marine archaeologist noting the absence of any potential archaeological

resources in the APE and certification from an operator representative confirming the survey

results and certifying that all seabed disturbing activities will be confined to the surveyed area.

(j) Air and Water Quality Information

Pursuant to NTL 2008‐G04, this section of the plan is not required.  For additional information

regarding air and water quality information, please see Air Quality Report, Attachment H‐1.

   

(k) Socioeconomic Information

The activities proposed under this plan are not expected to result in any of the following

situations; therefore this section is not required under NTL 2008‐G04:

o No support personnel are expected to be employed by the State of Florida as a result of

the activities proposed under this plan.

o No families or employees are expected to move to Florida as a result of the activities

proposed under this plan.

o No major supplies, services, energy or water are expected to be purchased within the

State of Florida as a result of the activities proposed under this plan.  

o No contractors or vendors within the State of Florida are not expected to be utilized as a

result of the activities proposed under this plan.

 

FOR PUBLIC RELEASE
Hess Corporation    Llano Field  

Supplemental EP    Garden Banks Block 386, OCS‐G10350

Appendix G

Waste and Discharge Information

(a) Projected Generated Wastes

Information regarding projected generated wastes is contained within the Water Quality Tables

included under Appendix G attachments.

(b) Projected Ocean Discharges

Information regarding projected ocean discharges is contained within the Water Quality Tables

included under Appendix G attachments.  

(c) Modeling Report

No trajectory modeling was performed, therefore no report is included.

  

FOR PUBLIC RELEASE
Hess Corporation    Llano Field  

Supplemental EP    Garden Banks Block 386, OCS‐G10350

Attachment G‐1

Water Quality Spreadsheets

  

FOR PUBLIC RELEASE
Composition Projected Amount Discharge rate Discharge M

Water Based Drilling Muds 65,065 bbls / well 21,688 bbls / day

Discharge at the mudline prior 

amount of unused fluid may be disch

Cuttings coated while drilling with WBM 2,783 bbls / well 928 bbls / day Discharged to mudline prior to rise

Cuttings coated with synthetic drilling

fluids, including drilled out cement 5,190 bbls / well 82 bbls / day

Dicharged to surface. Treated cutti

during drilling of the SBM intervals. Cu

a cuttings drye, substantial

Gray water from living quarters 25,800 bbls / well 9 chlo

Sanitary waste from living quarters,

control rooms and change rooms. 10,440 bbls / well 4 USCG a

Deck drainage from drilling floor 13,200 bbls / well 5 

N/A N/A N/A 

Sodium, Calcium Bromide 8,000 bbls / well 100 bbls / day

Discharge only the interface of comp

is estimated to be 50 ‐ 100 bbls. Bala

N/A N/A N/A 

Rejected water from the watermaker. 1,534,680 bbls / well 426 bbls / day 

Potable Water with 3% Erifon 100 bbls / well 100 bbls / day Discharge at the seafloor or with deck 

Uncontaminated seawater used to

maintain proper draft 420,000 bbls / well 117 bbls / day 

N/A N/A N/A 

Cement Slurry 1,000 bbls / well 500 bbls / day Discharged at sea

Sea Water with no additional chemicals 15,672,000 bbls / well 130,600 bbls / day 

Sea Water with no additional chemicals 15,672,000 bbls / well 130,000 bbls / day 

Produced water 1,000 bbls 1,000 bbls / day 

Projected generated waste

Type of Waste

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

Will you conduct well treatment, completion, or workover?

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

Well treatment fluids

Fire water

Cooling water

Excess cement at seafloor

Blowout prevent fluid

Cuttings wetted with synthetic‐based fluid

Desalinization unit discharge

Will drilling occur ? If yes, you should list muds and cuttings

Will humans be there? If yes, expect conventional waste

Domestic waste

Sanitary waste

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

Deck Drainage

Ballast water

Workover fluids

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

Well completion fluids

Projected ocean discharges

Water‐based drilling fluid

Cuttings wetted with water‐based fluid

All liquids are expressed in barrels and solids expressed in pounds. All volumes were calculated on a total, per well basis, unless otherwise noted.

General NPDES permit

Bilge water

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

Produced water

FOR PUBLIC RELEASE
Projected Generated

Wastes

Solid and Liquid Wastes

Transportation

Composition Transport Method Name/Location of Facility Amount 

N/A N/A N/A 

Internal olefin, ester/ SBM Cuttings boxes on supply boat Baroid ‐ Fourchon, LA 2,000 bb

N/A N/A N/A 

N/A N/A N/A N/A N/A N/A 

Refuse generated during operations:

paper, cardboard, plastic, glass and

aluminum.

Storage bins on the proper vessel / boat Gulf Offshore Logistics ‐  Fourchon, LA 168,000 pounds 

Used engine oil proper DOT containers on supply boat. Univar, Carencro, LA 

N/A N/A N/A 

N/A N/A N/A 

All liquids are expressed in barrels and solids expressed in pounds. All volumes were calculated on a total per well basis, unless otherwise noted.

Oil‐based drilling fluid or mud

Synthetic‐based drilling fluid or mud

Trash and debris

Used oil

Wash water

Chemical product wastes

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

Waste Dis

Will you have additional wastes that are not permitted for discharge? If yes, fill in the appropriate rows.

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

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

Type of Waste

Cuttings wetted with Water‐based fluid

Cuttings wetted with Synthetic‐based fluid

Cuttings wetted with oil‐based fluids

No production is proposed under this S‐EP

FOR PUBLIC RELEASE
Appendix H

Air Emissions Information

Hess Corporation (Hess) proposes to drill, log, complete and secure the LL4, LL5, LL5ST and LL6

well locations in Garden Banks Block 386. There is no production or pipeline installation

proposed under this Supplemental EP.  

Included in this section of the plan is the Air Quality Screening Checklist, prepared in accordance

with Notice to Lessees 2008‐G04 (Pages 13 to 17) addressing the above described exploratory

drilling activities.  

A dynamically positioned MODU, the Atwood Condor, will be used for all activities under this

Exploration Plan.  

A Modeling Report is not required under this Supplemental EP.  

Start Date End Date Total Days

Mob to GB 386 LL4 10/01/2012   10/02/2012   2

Drill, log, complete, secure LL4 10/03/2012   04/20/2013   200

Demob & move MODU to LL5 04/21/2013   04/21/2013   1

Drill, log, complete, secure LL5/LL5ST 04/22/2013   12/17/2013   240

Demob & move MODU to LL6 12/18/2013   12/18/2013 1

Drill, log, complete, secure, LL6 12/19/2013 07/07/2014 200

Release MODU & depart location 07/08/2014 07/08/2014 1

Total Drilling Days in 2012 = 90

Total Mob/Demob days in 2012 2

Total Drilling Days in 2013 = 363

Total Mob/Demob days in 2013 2

Total Drilling Days in 2014 = 187

Total Mob/Demob days in 2014 1

 

FOR PUBLIC RELEASE
2 of 2 

AIR EMISSIONS INFORMATION – Continued 

Helicopters, crew boats, and work/supply boats will be utilized to transport personnel and supplies 

to the proposed location at Garden Banks Block 386. It is anticipated the following will be utilized 

for transporting supplies and personnel. 

 

2012

Supply Boats (2) 3 round trips/week for 13 weeks of drilling operations (total of 78 daily trips) 

Service Boats 7 round trips/week for 13 weeks of drilling operations (total of 91 daily trips) 

Crew Boats 1 round trips/week for 13 weeks of drilling operations (total of 13 daily trips) 

Helicopters 8 round trips/week for 13 weeks of drilling operations (total of 104 daily trips) 

2013 

Supply Boats (2) 3 round trips/week for 52 weeks of drilling operations (total of 312 daily trips) 

Service Boats 7 round trips/week for 52 weeks of drilling operations (total of 364 daily trips) 

Crew Boats 1 round trips/week for 52 weeks of drilling operations (total of 52 daily trips) 

Helicopters 8 round trips/week for 52 weeks of drilling operations (total of 416 daily trips) 

2014 

Supply Boats (2) 3 round trips/week for 27 weeks of drilling operations (total of 162 daily trips) 

Service Boats 7 round trips/week for 27 weeks of drilling operations (total of 189 daily trips) 

Crew Boats 1 round trips/week for 27 weeks of drilling operations (total of 27 daily trips) 

Helicopters 8 round trips/week for 27 weeks of drilling operations (total of 216 daily trips) 

Total 

Supply Boats (2) 3 round trips/week for 92 weeks of drilling operations (total of 552 daily trips) 

Service Boats 7 round trips/week for 92 weeks of drilling operations (total of 644 daily trips) 

Crew Boats 1 round trips/week for 92 weeks of drilling operations (total of 92 daily trips) 

Helicopters 8 round trips/week for 92 weeks of drilling operations (total of 736 daily trips) 

The route utilized by each mode of transportation will normally be the most direct route from the 

existing shore base located at the EPS Dock in Fourchon, LA, to the Garden Banks Block 386 

location site. 

Complex Total Emissions were calculated by: 

Andrea Wallis, P.E. 

 Environmental Engineer 

 Phone: (337) 256-7670 

 E-mail: andrea@blueskyenviro.org 

Attachments to Air Emissions Information Section

- Air Quality Screening Checklist 

- Emission Calculation Sheet 

- Summary Sheet of Plan Total Emissions / Allowable 

- Vicinity Map 

FOR PUBLIC RELEASE
Hess Corporation    Llano Field  

Supplemental EP    Garden Banks Block 386, OCS‐G10350

Attachment H‐1

Air Quality Report

  

FOR PUBLIC RELEASE
EXPLORATION PLAN (EP)

AIR QUALITY SCREENING CHECKLIST

OMB Approval Expires: 12/31/

COMPANYAREABLOCKLEASEPLATFORMWELLCOMPANY CONTACTTELEPHONE NO.REMARKS

Note:

"Yes" "No"

No 1 Is any calculated Complex Total (CT) Emission amount (in tons) associated 

with your exploration activities more than 90% of the amounts calculated usthe following formulas: CT = 3400 D2/3 for CO, and CT = 33.3D for other apollutants (where D = distance to shore in miles)?

No 2 Do your emission calculations include any emission reduction measures 

or modifications?

No 3 Are your proposed exploration activities located east of 87.5 degrees W long

No 4 Do you expect to encounter H2S at concentration greater than 20 parts per No 5 Do your propose to flare or vent natural gas for more than 48 continuous ho

from any proposed well?

No 6 Do you propose to burn produced hydrocarbon liquids?

(Supplemental) Exploration Plan

Max default HP's were used for calculating emissions under this Exploratory Pl

Air Quality Screening Questions

Hess CorporationGarden Banks386OCS-G 10350Ultra-Deepwater DP Semi Submersible, Atwood CondorWells LL4, LL5, LL5ST and LL6Brittany Kight(713) 496-5866

FORM BOEM-0138 (October 2011 - Supersedes all previous versions of form BOEM-0138 which may not be used). Page 1 of 6

FOR PUBLIC RELEASE
EMISSIONS FACTORS

Fuel Usage Conversion Factors Natural Gas Turbines Natural Gas Engines Diesel Recip. Engine RE

SCF/hp-hr 9.524 SCF/hp-hr 7.143 GAL/hp-hr 0.0483 AP42 

Equipment/Emission Factors units PM SOx NOx VOC CO RENG Turbines gms/hp-hr 0.00247 1.3 0.01 0.83 AP42 3.2-NG 2-cycle lean gms/hp-hr 0.00185 10.9 0.43 1.5 AP42 NG 4-cycle lean gms/hp-hr 0.00185 11.8 0.72 1.6 AP42 NG 4-cycle rich gms/hp-hr 0.00185 10 0.14 8.6 AP42 Diesel Recip. < 600 hp. gms/hp-hr 1 1.468 14 1.12 3.03 AP42 Diesel Recip. > 600 hp. gms/hp-hr 0.32 1.468 11 0.33 2.4 AP42 Diesel Boiler lbs/bbl 0.084 2.42 0.84 0.008 0.21 AP42 1.3NG Heaters/Boilers/Burners lbs/mmscf 7.6 0.593 100 5.5 84 P42 1.4-1, 1NG Flares lbs/mmscf 0.593 71.4 60.3 388.5 AP42 1Liquid Flaring lbs/bbl 0.42 6.83 2 0.01 0.21 AP42 1.3-Tank Vapors lbs/bbl 0.03 E&P FFugitives lbs/hr/comp. 0.0005 API SGlycol Dehydrator Vent lbs/mmscf 6.6 La. DGas Venting lbs/scf 0.0034

Sulphur Content Source Value Units

Fuel Gas 3.33 ppm

Diesel Fuel 0.4 % weight

Produced Gas( Flares) 3.33 ppm

Produced Oil (Liquid Flaring) 1 % weight

FORM BOEM-0138 (October 2011 - Supersedes all previous versions of form BOEM-0138 which may not be used). Page 2 of 6

FOR PUBLIC RELEASE
SUMMARY

COMPANY AREA BLOCK LEASE PLATFORM WELL

Hess Corporation Garden Banks 386 OCS-G 10350

Ultra-Deepwater DP Semi Submersible, Atwood Condor

Wells LL4, LL5, LL5ST and LL6

Emitted Substance

Year

 PM SOx NOx VOC CO

2012 15.45 70.68 529.82 15.94 115.60

2013 52.99 242.28 1816.26 54.67 396.27

2014 35.78 163.73 1227.25 36.91 267.76

Allowable 4329.00 4329.00 4329.00 4329.00 87251.82

FORM BOEM-0138 (October 2011 - Supersedes all previous versions of form BOEM-0138 which may not be used). Page 6 of 6

FOR PUBLIC RELEASE
Hess Corporation    Llano Field  

Supplemental EP    Garden Banks Block 386, OCS‐G10350

Appendix I

Oil Spills Information

(a) Oil Spill Response Planning

All the proposed activities and facilities in this EP will be covered by the Oil Spill Response Plan

filed by Hess Corporation (Company Number 00059) in accordance with 30 CFR 254, last

approved on May 9, 2012.

(b) Spill Response Sites

The following spill response sites will be used in the event an oil spill occurs as a result of the

activities proposed herein:

Primary Response Equipment Location Pre‐Planned Staging Location

Houma, LA Fourchon, LA

(c) OSRO Information

Hess is a member of the Clean Gulf Associates (CGA) cooperative.  Membership provides for the

use of CGA equipment which is stored, maintained, and operated through an alliance agreement

by Marine Spill Response Corporation (MSRC). The MSRC STARS network provides for the closest

available personnel as well as an MSRC supervisor to operate the equipment.   Hess is also a

member of the National Response Corporation (NRC).  Membership provides access to the NRC‐

owned and dedicated resources, including the Response Network’s equipment.   

Additionally, Hess Corporation is a member of both the Helix Well Containment Group (HWCG)

and Marine Well Containment Company (MWCC).

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Hess Corporation    Llano Field  

Supplemental EP    Garden Banks Block 386, OCS‐G10350

(d) Worst Case Scenario Determination  

Category Regional OSRP EP

Type of Activity1 MODU MODU

Facility Location

(area/block) Garden Banks 386 Garden Banks 386

Facility Designation2 Well Location LL5‐ST Well Location LL5‐ST

Distance to Nearest

Shoreline (miles) 130 miles 130 miles

Volume3

Storage tanks (total)

Flowline (on facility)

Lease term pipelines

Uncontrolled blowout

(volume per day)

Total Volume

0 bbls

0 bbls

0 bbls

  228,936 bbls

  228,936 bbls

0 bbls

0 bbls

0 bbls

  228,936 bbls

  228,936 bbls

Type of Oil(s) ‐ (crude oil,

condensate, diesel) Crude Crude

API Gravity(s)4 33.1° 33.1°

Footnotes:

1. Types of activities include pipeline, platform, caisson, subsea completion or manifold, and mobile drilling rig.

2. E.g., Well No. 2, Platform JA, Pipeline Segment No. 6373.

3. Take your regional OSRP worst‐case scenario volume from the appropriate section of your regional OSRP. For EP’s, the

worst‐case scenario volume is the daily volume possible from an uncontrolled blowout. Determine this volume using the

provisions of 30 CFR 30 CFR 254.47(b). For DOCD’s, determine the volume of your worst‐case scenario using the

provisions of 30 CFR 30 CFR 254.47(a) or (b), as appropriate.

4. Provide API gravity of all oils given under “Type of Oil(s)” above. Estimate for EP’s.

Since Hess Corporation has the capability to respond to the appropriate worst case spill scenario

included in its regional OSRP approved on May 9, 2012, and since the worst‐case scenario

determined for our EP does not replace the appropriate worst case scenario in our regional

OSRP, I hereby certify that Hess Corporation 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 EP.

(e) Calculations and Assumptions Used to Calculate WCD

[PROPRIETARY INFORMATION OMITTED]

FOR PUBLIC RELEASE
Hess Corporation    Llano Field  

Supplemental EP    Garden Banks Block 386, OCS‐G10350

Attachment I‐5

Oil Spill Response Discussion

FOR PUBLIC RELEASE
Hess Corporation    Llano Field  

Supplemental EP    Garden Banks Block 386, OCS‐G10350

Oil Spill Response Discussion

Upon notification of a release and mobilization of the response, either a fixed‐wing aircraft or helicopter

would be dispatched as promptly as possible (considering available daylight hours, weather conditions

and other safety factors) to conduct visual surveillance at the spill source. If necessary and safe, this

surveillance could be supplemented through use of vessels as well. The effectiveness of many response

technologies (such as in‐situ burning, dispersant application and mechanical recovery) can be enhanced

through collaboration with air‐based spotters, who can guide these systems to the oil concentrations

and coordinate simultaneous operations (SIMOPS). Air‐based spotters may be equipped with air to

marine/ground communication equipment to facilitate communications with marine‐  and land‐based

response assets. Vessel locations may also be monitored in real‐time using vessel‐tracking technologies

(such as Automated Identification Systems (AIS) data, GPS‐based tracking, cell phone data, etc.), which

can facilitate vessels being deployed for optimal recovery.  

Simultaneous operations (SIMOPS) may involve different companies working in close proximity on

identical and/or different tactical objectives. SIMOPS can be either subsea operations, surface

operations or a combination of both. These operations must be well planned and coordinated. SIMOPS

will be evaluated daily and coordinated based on the response efforts needs, as well as, additional

criteria’s (e.g. meteorological conditions, sea state, etc.). Regular communications will be established

and maintained during all SIMOPS activities

Simultaneous operations (SIMOPS) may involve different companies working in close proximity on

identical and/or different tactical objectives. SIMOPS can be either subsea operations, surface

operations or a combination of the two. These operations must be well‐planned and coordinated.

SIMOPS will be evaluated daily and coordinated based on an array of criteria, including: the needs of

the response efforts, meteorological conditions, sea state, etc. Regular communications will be

established and maintained during all SIMOPS activities.  

SIMOPS activities may include but are not limited to the following:  

•  

•  

•  

•  

•  

•  

Dispersant application (Aerial, Vessel, and Subsea)  

In‐situ burning  

Mechanical recovery  

Shoreline response (i.e. booming strategies)  

Well containment / source control  

Surveillance activities

Offshore Response

Primary offshore response would involve mechanical recovery. Offshore response strategies may

include attempting to skim utilizing NRC’s Oil Spill Response Vessels (OSRVs), Oil Spill Response Barges

(OSRBs), VOO Boats, and Fast Response Units, which have a combined derated recovery rate of 237,667

barrels/day. Temporary storage associated with the identified skimming and temporary storage

equipment equals 289,531 barrels. Other technologies (like GPS‐based vessel tracking systems) may be

used to facilitate coordination of marine resources. This equipment may be facilitated by air‐based

spotters that can guide these systems to oil concentrations. During night‐time operations, skimming

FOR PUBLIC RELEASE
Hess Corporation    Llano Field  

Supplemental EP    Garden Banks Block 386, OCS‐G10350

activities could be facilitated through the use of alternative spill surveillance technologies (such as

infrared [IR] and X‐band radio systems) to guide skimming vessels to sufficient concentrations of oil. The

specific technologies used will be chosen based on availability, suitability, OSRO recommendations, and

other considerations that are specific to the situation.  

Primary offshore response would involve mechanical recovery. Offshore response strategies may

include attempting to skim utilizing NRC’s Oil Spill Response Vessels (OSRVs); Oil Spill Response Barges

(OSRBs); VOO Boats; and Fast Response Units, which have a combined derated recovery rate of

255,496 barrels/day. Temporary storage associated with the identified skimming and temporary

storage equipment totals 291,531 barrels. Other technologies (like GPS‐based vessel tracking systems)

may be used to facilitate coordination of marine resources. This equipment may be facilitated by air‐

based spotters that can guide these systems to oil concentrations. During night‐time operations,

skimming activities could be facilitated through the use of alternative spill surveillance technologies

(such as infrared [IR] and X‐band radio systems) to guide skimming vessels to sufficient concentrations

of oil. The specific technologies used will be chosen based on availability, suitability, OSRO

recommendations, and other considerations that are specific to the situation.  

   

Offshore response strategies include, but are not limited, to the following:

•  

Mobilize mechanical recovery resources, including vessels (both OSRVs and Vessels of

Opportunity), barges, ocean boom, skimming equipment, and spotter/surveillance aircraft. Begin

deploying mechanical recovery resources as close to the source as possible to contain and collect

concentrated oil in a timely and effective manner. Radio communications will be established

between spotter aircraft and other surveillance systems (including AIS) with skimming vessels and

barges to direct vessels to locations of concentrated oil to ensure maximum effectiveness and

efficiency of mechanical recovery equipment.  

•  

Mobilize dispersant resources to pre‐approved and approved locations for both aerial and boat

application in areas where oil cannot be mechanically recovered. Subsea dispersant application

equipment may be mobilized at the discretion of the RRT and requires approval from the RRT. If

approved, subsea dispersant application with be in accordance with RRT 6 guidelines.  

•   Mobilize in‐situ burn resources outside the vicinity of the source to collect and burn oil in heavily

concentrated locations. Fire boom will be deployed in a U‐configuration.

•  

Mobilize offshore vessels equipped with remote sensing technologies (radar, infrared camera) to

aid in night time operations and slick tracking. Remote sensing technologies assist skimming

vessels in identifying thick areas of oil to enhance encounter rate and EDRC.  

•  

Maintain an effective and well‐coordinated response effort for the length of time to control the

source of the discharge, which may involve drilling a relief well.  This effort is to be maintained up

to the point when the Federal On‐Scene Coordinator determines the response effort complete.

FOR PUBLIC RELEASE
Hess Corporation    Llano Field  

Supplemental EP    Garden Banks Block 386, OCS‐G10350

Mechanical oil spill response uses physical barriers (boom) and mechanical devices (skimmers) to

redirect and remove oil from the surface of the water.  

Mechanical cleanup strategies include, but are not limited, to the following:  

•  

Skimming systems will deploy boom in a variety of different configurations. Generally, boom will

be deployed in a J‐configuration in a single skimming unit, which requires only one assist vessel to

attend the boom. These single skimming units will locate heavily concentrated oil with assistance

from spotters and remote sensing technologies in order to ensure enhanced encounter rate and

effective recovery. Boom will be deployed in a U‐configuration when skimming vessels or barges

have access to two assist vessels. This configuration maximizes the swath width and containment

capacity. Boom may be deployed in a U‐configuration with an open apex to funnel oil to awaiting

skimming vessels.  

•  

Vessels of opportunity (VOO) equipped with skimming systems will be deployed to locations of

recoverable oil. For locations with light oil that cannot be recovered mechanically, vessels of

opportunity will be equipped with sorbent materials to recover this light oil.  

•  

In order to increase encounter rate, slick containment systems will be directed to locations of

heavily concentrated oil from spotter aircraft and vessels with remote sensing technology. Once

the oil has been contained within the booms, the oil is dumped into the path of a skimming

vessel. Boom also may be configured into a U‐configuration with an open apex to funnel oil to

awaiting skimming vessels.  

•  

Oil that escapes the above assets and moves shoreward will be collected by vessels of opportunity

that deploy sorbent boom, collection nets or other types of equipment that absorb surface oil.

These assets will be deployed as task forces that can rapidly respond to light oil.  

Current proven and available sensing technology for tracking oil at night includes hand‐held, boat‐

mounted and aircraft‐mounted infrared sensing. Hess understands that multiple new oil sensing

technologies (radar, satellite imagery, fluorometry, etc.) are being reviewed and developed by the

industry and as they become more mature, proven and available to the industry, Hess will work with our

OSROs to include these improvements in our response capability. These and any other new oil sensing

technologies that become available will be deployed with the purpose of improving the ability of keeping

deployed oil skimming platforms in the most highly concentrated areas of spilled oil and may be used to

potentially improve the capabilities to skim beyond traditional daylight hours. However the latter

capability can only be implemented taking all aspects of safe operations in account and ensuring that

there is no additional risk to human life.

Dispersant Application

Depending on proximity to shore and water depth, dispersants may be a viable response option. If

appropriate, 4 to 5 sorties (1,000 gallons or 2,000 gallons per sortie) may be used. The DC‐3 with turbo

prop has a 2,000 gallon capacity.   Using a 1:20 application rate, 90% effectiveness, and assuming 4‐5

sorties per day the systems could disperse approximately 7,704 to 9,630 barrels of oil per day based on

the NOAA Dispersant Planner. Additionally, subsea dispersant application and boat spray application are

other methods for applying dispersants. Subsea dispersant application requires approval from the

appropriate RRT. Additional dispersant supplies are available and may be acquired from other sources

FOR PUBLIC RELEASE
Hess Corporation    Llano Field  

Supplemental EP    Garden Banks Block 386, OCS‐G10350

through industry agreements at the direction of the FOSC and appropriate RRT. Priorities for dispersant

use and rationing of existing supplies will be determined on an incident specific basis to allow for

maximum effectiveness of dispersants. Dispersant use will be dictated by approval, safety, weather, and

sea states before application and coordinated with Unified Command.  

Hess has contracted with Marine Well Containment Company for a subsea dispersant package. Subsea

dispersant application has been found to be highly effective at reducing the amount of oil reaching the

surface; however, approval is required from the appropriate Regional Response Team (RRT) prior to use.

Additional data collection, laboratory tests and field tests will help in facilitating the optimal application

rate and effectiveness numbers. For planning purposes, Hess assumes a 1:100 application rate, at 90%

effectiveness (based on accepted industry dispersant effectiveness standards), and a system flow rate of

8‐11 gallons per minute (approximately 11,500 to 16,000 gallons of dispersant per day). Using these

assumptions, the system has the potential to disperse approximately 24,500 to 34,000 barrels of oil per

day.  

Dispersant use will be dictated by approval, safety, weather, and sea states before application and

coordinated with Unified Command. In addition, Hess will assess the situation and can make notification

within 48 hours of the initial spill to begin ramping up dispersant production through Nalco. All

dispersant applications will be in compliance with RRT 6 guidelines.  

In‐situ Burning

Open‐water in‐situ burning (ISB) also may be used as a response strategy, depending on the

circumstances of the release. ISB services may be provided by the primary OSRO contractors. If

appropriate conditions exist and approvals are granted, one or multiple ISB task forces could be

deployed offshore. Task forces typically consist of two to four fire teams, each with two vessels capable

of towing fire boom, guide boom or tow line with either a handheld or aerially‐deployed oil ignition

system. At least one support/safety boat would be present during active burning operations to provide

logistics, safety and monitoring support. Depending upon a number of factors, up to 4 burns per 12‐hour

day could be completed per ISB fire team. Most fire boom systems can be used for approximately 8‐12

burns before being replaced. Fire intensity and weather will be the main determining factors for actual

burns per system. Although the actual amount of oil that will be removed per burn is dependent on

many factors, recent data suggests that a typical burn might eliminate approximately 750 barrels. For

planning purposes and based on the above assumptions, a single task force of four fire teams with the

appropriate weather and safety conditions could complete four burns per day and remove up to

~12,000 bbls/day. In‐situ burning nearshore and along shorelines may be a possible option based on

several conditions and with appropriate approvals. In‐situ burning along certain types of shorelines may

be used to minimize physical damage where access is limited or if it is determined that

mechanical/manual removal may cause a substantial negative impact on the environment. All safety

considerations will be evaluated. In addition, Hess will assess the situation and can make notification

within 48 hours of the initial spill to begin ramping up fire boom production through contracted

OSRO(s).  

Slick Containment

Slick (fresh oil) containment systems may be deployed (provided it is safe to do so) in thick, fresh oil to

minimize further spreading of oil on the water’s surface. These systems would typically consist of two

offshore vessels (capable of trolling speeds of 0.5 knots) towing between 1,000 to 1,500 feet of offshore

FOR PUBLIC RELEASE
Hess Corporation    Llano Field  

Supplemental EP    Garden Banks Block 386, OCS‐G10350

boom in a “U” or “V” configuration. The containment systems would allow fresh oil to be contained,

concentrated and diverted to skimming systems and/or in‐situ burn task forces, increasing their encounter

rate and containment efficiency in order to support enhanced skimming and burning operations.

Source Control / Subsea Containment

The initial response to a well blowout would be an attempt to activate the blowout preventers and close

the well. The Source Control team will be stood up immediately. The primary well control provider, Marine

Well Containment Company (MWCC), and/or the secondary well control provider, Helix Well Containment

Group (HWCG), would be notified in the event of a blowout. The first step will be determining if the well

can be capped and killed. If the well cannot be capped, the relief well(s) operations may start as soon as

possible.  

Subsea containment resources would be mobilized in the event of an uncontrolled well blowout.

Subsea containment incorporates simultaneous operations to cap or contain the flow of oil within the

well, contain the oil outside of the well and collect at surface facilities or vessels and chemically

disperse the oil at the well head. MWCC has been contracted to supply the subsea dispersant

applications.  

Source control activities include, but are not limited, to the following:

• Notifications to regulatory authorities, MWCC, and support contractors regarding well control

incident  

• Site assessment, initial response, and well monitoring  

• Notification and activation of any equipment and contract services outside of MWCC will be initiated

by Hess (e.g. shuttle tankers, helicopters, etc.)

• Notification, as needed, to members of MWCC to assist Hess’s Source Control Group during source

control operations  

• Debris Removal and Lower Marine Riser Package (LMRP) Recovery Considerations, if applicable  

• Coordination of ROVs, support vessels, intervention vessels, subsea dispersant equipment, debris

removal tools, umbilical, chemical delivery, pumping services, and other equipment for WCD scenarios  

• Run Intervention Riser System  

• Well Capping and Shut‐in Operation Activities  

In the unlikely event of a well control issue, Hess, as a member of the Marine Well Containment

Company (MWCC), has access to an Interim Containment Response System (ICRS) that can be rapidly

mobilized through the MWCC. The ICRS consists of equipment to contain and capture a hydrocarbon

release from a damaged deepwater well. The primary component of the ICRS for well control is the

capping stack. Additional components include a subsea dispersant application system, hydrate inhibition

system, and a “top hat” (designed to recover discharged oil). MWCC will provide containment response

support through a combination of equipment and services (owned, via mutual aid commitments, or

through agreements with MWCC). Under direction of Hess, MWCC will participate with the response

team to support direction of MWCC equipment and tools.  

For additional detailed information on these systems, their components, and deployment times, refer to

the current Marine Well Containment Company Interim Containment Response System Functional

Specifications USWC‐ED‐BPFEP‐000001 provided to BSSE by MWCC. Information on how these systems

will be deployed to respond to a specific well, can be found in the NTL 2010‐N10 information submitted as

a supplement to the individual “Application for Permit to Drill”.

FOR PUBLIC RELEASE
Hess Corporation    Llano Field  

Supplemental EP    Garden Banks Block 386, OCS‐G10350

Primary Component System Capacity for the ICRS

Marine Well Interim Containment Response System (ICRS) Diagram

FOR PUBLIC RELEASE
Hess Corporation    Llano Field  

Supplemental EP    Garden Banks Block 386, OCS‐G10350

In addition to MWCC, and in the event that it is necessary for secondary well control support, Hess has

contracted with Helix Energy Solutions Group, Inc. to provide services and the Helix Fast Response System

(HFRS) for subsea well control. Hess is a member of the Helix Well Containment Group (HWCG), a

consortium of deepwater operators in the Gulf of Mexico that has come together with the common goal

of expanding capabilities to quickly and comprehensively respond to a subsea well control incident. HWCG

members have entered into a Mutual Aid Agreement to facilitate resource‐sharing if the need arises.

Outside of this arrangement it may be necessary to have other assets in place to carry out other aspects of

the Well Containment Plan (WCP) as outlined in the diagram below.

Hess has identified base potential service providers to assist as third party service providers. These

contractors have specific functions as indicated in the reference data of the WCP. Hess has master

service agreements (MSA) in place with contractors for services deemed necessary in response to or

support of well containment incidents.  

Well Containment: The HFRS consists of the primary core equipment and services for the well

containment response. The specific equipment necessary for capping operations may be viewed at

http://www.helixesg.com/HFRS/The‐Helix‐DCS‐System/.  

Well Containment System: The containment system includes a 10k psig capping stack, a 15k psig

capping stack, a riser intervention system capable of operating in 8000 feet of water (10,000 feet water

depth capability anticipated by the end of June 2011), the Q4000 intervention vessel (used during the

Deepwater Horizon response), and all necessary equipment to complete the intervention system. In

addition, the Helix Producer I (HP1) is an integral part of this system and is designated in the plan to be

utilized a floating production unit (FPU).  

The HFRS is made of many components and resources in order to achieve the goal of a successful

capping operation. The utilization of these components requires the assistance of vendors / contractors

to achieve each evolution of the operation as outlined in the WCP. The successful mobilization and

implementation of this system is orchestrated by procedures and processes as outlined within the WCP.

Additional support and service systems also identified within the WCP is a key part of the configuration

and response based on the response scenario matrix listed in the plan. The WCP has reference data and

service providers identified that incorporates complete implementation of the wellcap and riser system

FOR PUBLIC RELEASE
Hess Corporation    Llano Field  

Supplemental EP    Garden Banks Block 386, OCS‐G10350

as well as other considerations such as debris removal, chemical dispersant delivery and pumping

services.  

In addition to the previously discussed response mechanisms for containment and the organization, within

Hess, designated to fulfill the supervision of each aspect, the following table outlines the well containment

activity schedule as a planning timeline.

The assumption for this timeline, as indicated in the Well Activity Schedule, is that there are many possible

scenarios and not any one solution can be counted on as the one and only possible means to complete a

successful capping operation. The table below incorporates all of the various scenarios as outlined in the

WCP and makes assumptions based on calculated timelines.

FOR PUBLIC RELEASE
Hess Corporation    Llano Field  

Supplemental EP    Garden Banks Block 386, OCS‐G10350

LA CZMA:  Estimated Time to Contain Surface Hydrocarbons

Based on the anticipated worst case discharge scenario, Hess Corporation (Hess) expects to be onsite

with contracted oil spill recovery equipment with adequate response capacity to contain and recover

surface hydrocarbons, and prevent land impact to the maximum extent practicable, within an estimated

48 hours (based on the equipment’s Effective Daily Recovery Capacity (EDRC)). Hess will continue to

commit additional on‐water mechanical recovery resources as well as apply dispersants and in‐situ

burning needed and as approved, under the supervision of the USCG Captain of the Port (COTP) and the

Regional Response Team (RRT).

Nearshore and Shoreline Protection

If the spill went unabated, shoreline impact would depend upon existing environmental conditions.

Nearshore response may include the deployment of shoreline boom on beach areas, or protection and

sorbent boom on vegetated areas. Strategies would be based upon surveillance and real time

trajectories provided by The Response Group that depict areas of potential impact given actual sea and

weather conditions. Strategies from the Area Contingency Plan, The Response Group and Unified

Command would be consulted to ensure that environmental and special economic resources would be

correctly identified and prioritized to ensure optimal protection. The Response Group shoreline

response guides depict the protection response modes applicable for oil spill clean‐up operations. Each

response mode is schematically represented to show optimum deployment and operation of the

equipment in areas of environmental concern. Supervisory personnel have the option to modify the

deployment and operation of equipment allowing a more effective response to site‐specific

circumstances.  

Mechanical Cleanup Methods

Near shore mechanical recovery resources will be deployed to contain and collect oil prior to reaching

the shoreline, minimizing the amount of oil that may impact the shoreline. In areas of shallow water, it

may be possible to collect or corral the oil with ocean boom and take it to deeper water or low‐current

areas that have better skimmer access and higher recovery rates. Sorbent boom and snare boom may

be utilized to recovery light sheens and more viscous oils. Sorbent boom is designed primarily to absorb

oil although it can act as a protective measure against thin oil sheens under very quiet water conditions.

Snare boom (pom‐poms tied onto a line) is effective as a sorbent of more viscous oils under higher wave

and current conditions. In any current, sorbent boom can contain only the thinnest sheens. When used

with conventional booms, sorbents can be placed outside of the boom to pick up small amounts of

escaping oil, or inside the boom to absorb small amounts of contained oil.  

FOR PUBLIC RELEASE
Hess Corporation    Llano Field  

Supplemental EP    Garden Banks Block 386, OCS‐G10350

Shoreline Protection

The Response Group shoreline response guides depict the protection response modes applicable for oil

spill clean‐up operations, and are compliant with various Area Contingency Plans. Each response mode is

schematically represented to show optimum deployment and operation of the equipment in areas of

environmental concern. Supervisory personnel have the option to modify the deployment and operation

of equipment allowing a more effective response to site‐specific circumstances. Booming strategies will be

implemented to exclude oil from impacting priority resources, and may be diverted to collection areas for

recovery. The Shoreline Boom table outlines various types of boom that may be deployed to protect the

shoreline:

Shoreline boom strategies include, but are not limited, to the following:

Near Shore Booming   When oil impact threatens shoreline or marshes. Medium size boom (~18”) to

deflect or contain oil or use to prevent impact to sensitive areas.  

Bottom‐Seal Boom  

Typically used in shallow water with higher‐currents. The shallow skirt minimizes

current and allows it to conform to the substrate so that it can continue to act as

during changing tides or lower water levels. Bottom seal boom uses ballast tube

with water and lays on the bottom to provide a seal against oil passage.

Inland Boom  

Inland boom is the smallest conventional boom and is designed for deployment

in very shallow water; as the draft is only 6‐12 inches. It is normally deployed in

more protected waters where there is little or no wave action.  

Sorbent Boom  

Deployed to absorb oil and act as a protective measure against thin oil sheens

under very quiet water conditions. Snare boom may be used for more viscous

oils under higher wave and current conditions. Sorbent boom can contain only

the thinnest sheens.  

For additional information regarding Offshore, Nearshore and Shoreline response strategies and tactics,

refer to the MSRC Gulf of Mexico Deep Blue Response Tactics Guidebook, Dual MSRC/CGA Edition, the

local Area Contingency Plans and the appropriate Response Group’s Shoreline Response Strategy

Guidebook.  

Wildlife Support

If wildlife is threatened due to a spill, CGA and NRC have an abundance of resources available to Hess,

which can be utilized to protect and/or rehabilitate wildlife.  

Oil Spill Response Discussion – Less than 100 bbls

In the event of a spill less than 100 bbls at GB 386, our primary response in normal or adverse weather

conditions would be an Oil Spill Response Vessel (OSRV) from the National Response Corporation (NRC)

and an Oil Spill Response Barge (OSRB) from Clean Gulf Associates (CGA). The initial response would

likely consist of Vessel of Opportunity Skimming Systems (VOSS) an OSRV from Galveston, Texas, that is

approximately 198 miles from the location at GB 386, and an OSRB from Houma, Louisiana, that is

approximately 182 miles from the location at GB 386. Derated recovery capacity of the OSRV would be

26,125 BOPD, and storage capacity would be 300 barrels. With a maximum procurement time of 2

hours, a loadout time of 1 hour, a deployment time of 1 hour, and a maximum planning run time of 24

hours (198 GOM miles at 12 knots). Actual response times are generally quicker than planning times,

FOR PUBLIC RELEASE
Hess Corporation    Llano Field  

Supplemental EP    Garden Banks Block 386, OCS‐G10350

since the vessel can be mobilized within one hour, and the actual maximum speed of the vessel

approaches 25 knots, weather permitting. As with any spill, additional "cascading" response equipment

would be mobilized to the site from various OSRO bases like Belle Chasse, New Iberia, Galveston, Lake

Charles, Houma, and Port Arthur. For spills larger than 100 barrels, dispersants may also be mobilized by

plane from Stennis, MS, pending approval from the USCG.   

1F Additional Measures: Safety, pollution prevention and early spill detection measures in addition to 30 CFR 250.

FOR PUBLIC RELEASE
Staging ETA

Loadout Time

ETA to Site

Deployment 

Time

Total ETA

42" Inflatable Boom (ft) 1000

Personnel 8

Safety Monitor 2

42" Inflatable Boom (ft) 1000

Personnel 8

Safety Monitor 2

42" Inflatable Boom (ft) 1000

Personnel 8

Safety Monitor 2

42" Inflatable Boom (ft) 1000

Personnel 8

Safety Monitor 2

42" Inflatable Boom (ft) 1000

Personnel 8

Safety Monitor 2

42" Inflatable Boom (ft) 1000

Personnel 8

Safety Monitor 2

42" Inflatable Boom (ft) 1000

Personnel 8

Safety Monitor 2

42" Inflatable Boom (ft) 1000

Personnel 8

Safety Monitor 2

42" Inflatable Boom (ft) 1000

Personnel 8

Safety Monitor 2

42" Inflatable Boom (ft) 1000

Personnel 8

Safety Monitor 2

42" Inflatable Boom (ft) 1000

Personnel 8

Safety Monitor 2

42" Inflatable Boom (ft) 1000

Personnel 8

Safety Monitor 2

42" Inflatable Boom (ft) 1000

Personnel 8

Safety Monitor 2

TOTAL SLICK CONTAINMENT BOOM AVAILABLE (FEET) 13,000

1 12 1 18 Offshore Slick * >110' Utility Boat 2

Containment System

NRC

800-899-4672 New Iberia, LA Fourchon, LA 165 4

1 12 1 18 Offshore Slick * >110' Utility Boat 2

Containment System

NRC

800-899-4672 New Iberia, LA Fourchon, LA 165 4

1 12 1 18 Offshore Slick * >110' Utility Boat 2

Containment System

NRC

800-899-4672 New Iberia, LA Fourchon, LA 165 4

1 12 1 18 Offshore Slick * >110' Utility Boat 2

Containment System

NRC

800-899-4672 New Iberia, LA Fourchon, LA 165 4

1 12 1 18 Offshore Slick * >110' Utility Boat 2

Containment System

NRC

800-899-4672 New Iberia, LA Fourchon, LA 165 4

1 12 1 18 Offshore Slick * >110' Utility Boat 2

Containment System

NRC

800-899-4672 New Iberia, LA Fourchon, LA 165 4

1 12 1 18 Offshore Slick * >110' Utility Boat 2

Containment System

NRC

800-899-4672 New Iberia, LA Fourchon, LA 165 4

1 12 1 18 Offshore Slick * >110' Utility Boat 2

Containment System

NRC

800-899-4672 New Iberia, LA Fourchon, LA 165 4

1 12 1 18 Offshore Slick * >110' Utility Boat 2

Containment System

NRC

800-899-4672 New Iberia, LA Fourchon, LA 165 4

1 12 1 18 Offshore Slick * >110' Utility Boat 2

Containment System

NRC

800-899-4672 New Iberia, LA Fourchon, LA 165 4

1 12 1 18 Offshore Slick * >110' Utility Boat 2

Containment System

NRC

800-899-4672 New Iberia, LA Fourchon, LA 165 4

12 1 18 Offshore Slick * >110' Utility Boat 2

Containment System

NRC

800-899-4672 New Iberia, LA Fourchon, LA 165 4

GB 386 (Exploratory) WCD

Sample Offshore Slick Containment Activation List

* - These components are additional operational requirements that must be procured by OSROs in addition to the system identified.

Containment 

System

Supplier 

& Phone Warehouse Containment Package

Quantity

Staging Area

Distance to

Site from 

Staging (Miles)

Response Times (Hours)

1 12 1 18 Offshore Slick * >110' Utility Boat 2

Containment System

NRC

800-899-4672 New Iberia, LA Fourchon, LA 165 4

1

FOR PUBLIC RELEASE
© The Response Group 2/23/2012 Staging ETA Loadout Time Deployment Time Total ETA

Containment Boom - 18" to 24"

Response Boats - 14' to 20'

Response Boats - 21' to 36'

Portable Skimmers

Shallow Water Skimmers

Bird Scare Cannons

Response Personnel

Containment Boom - 18" to 24"

Containment Boom - 6" to 10"

Response Boats - 14' to 20'

Response Boats - 21' to 36'

Portable Skimmers

Shallow Water Skimmers

Bird Scare Cannons

Response Personnel

Wildlife Trailer

Contract Truck (Third Party)

Personnel (Responder/Mechanic)

Containment Boom - 18" to 24"

Response Boats - 14' to 20'

Portable Skimmers

Response Personnel

Containment Boom - 18" to 24"

Containment Boom - 6" to 10"

Response Boats - 14' to 20'

Response Boats - 21' to 36'

Portable Skimmers

Shallow Water Skimmers

Bird Scare Cannons

Response Personnel

Containment Boom - 18" to 24"

Response Boats - 14' to 20'

Response Personnel

Containment Boom - 18" to 24"

Containment Boom - 6" to 10"

Response Boats - 14' to 20'

Response Boats - 21' to 36'

Portable Skimmers

Shallow Water Skimmers

Response Personnel

Containment Boom - 18" to 24"

Containment Boom - 6" to 10"

Response Boats - 14' to 20'

Response Boats - 21' to 36'

Portable Skimmers

Response Personnel

Containment Boom - 18" to 24"

Containment Boom - 6" to 10"

Response Boats - 14' to 20'

Portable Skimmers

Response Personnel

TRI-STATE

302-737-9543 Newark, DE Wildlife Specialist - Personnel 6 to 12 Cameron, LA

3 1 0 4

1 2

24 1 0 25

3.5 1 1 5.5

2.5

1

3.5 1 0 4.5

4.5

WR&E

281-731-8826 Houston, TX Wildlife Specialist - Personnel 6 to 20 Cameron, LA

1

500'

6

New Iberia, LA

1.5 4.5

1 4.5

WR&E

281-731-8826

Baton Rouge, 

LA Wildlife Specialist - Personnel 6 to 20 Cameron, LA

1 MSRC

800-OIL-SPIL

Lake Charles, 

LA

1 Cameron, 

LA

2

5

6

1

8

25

19000'

Cameron, 

LA

9 to 18

1000'

Cameron, 

LA

3

2

ES&H Environmental

877-437-2634 Fourchon, LA

ES&H Environmental

877-437-2634 Houma, LA

AMPOL

800-482-6765

200'

3

3

2

11

25

1

200

Harvey, LA 1

4.5

1 6

15,000'

38

27,000'

Cameron, 

LA

12

Oilmop

800-645-6671 New Iberia, LA

3,500'

Cameron, 

LA 2.5

8

1

6

1

20

USES

Environmental

888-279-9930

Geismar, LA

1

4

1 1

GB 386 (Exploratory) WCD

Sample Shoreline Protection & Wildlife Support List

Supplier & Phone Warehouse Equipment Listing

Quantity

Staging Area

Response Times (Hours)

18

9

24

14750' Cameron, 

LA 4.5

500'

10

1

15

1 1 6.5

1 AMPOL

800-482-6765 1

1 7.5

1

1

1000'

Cameron, 

LA 5.5

Oilmop

800-645-6671

Belle Chasse, 

LA

21,000'

Cameron, 

LA 4.5

6.5

8

15 to 30

1000'

13

5 1 6.5

USES

Environmental

888-279-9930

Meraux, LA

9000'

Cameron, 

LA

FOR PUBLIC RELEASE
© The Response Group 2/23/2012 Staging ETA Loadout Time ETA to Site Deployment Time

Total ETA

Offshore Barge 1

Personnel 4

* Offshore Tug 1

Offshore Barge 1

Personnel 4

* Offshore Tug 1

Offshore Barge 1

Personnel 4

* Offshore Tug 1

Vikoma Sea Skim 1

43" Boom 2100'

Personnel 4

17' Boom Boat 1

110' Utility Boat 1

Bladders 3

Personnel 4

* Offshore Tug 1

Don Wilson Skimmer 1

43" Expandi Boom 500'

Personnel 4

* Utility Boat 1

Crew Boat 1

Don Wilson Skimmer 1

43" Expandi Boom 500'

Personnel 4

* Utility Boat 1

Crew Boat 1

Rope Mop/VTU Skimmer 1

18" - 21" Boom 200'

Personnel 4

Marine Tank 1

* 110' Utility Boat 1

Don Wilson Skimmer 1

43" Expandi Boom 500'

Personnel 4

* Utility Boat 1

Crew Boat 1

Marco/VTU Skimmer 1

43" Boom 200'

Personnel 4

Marine Tank 1

* 110' Utility Boat 1

12 1 16

Portable 

Bladders

NRC

800-899-4673

Morgan City. 

LA N/A 300 Morgan City, 

LA 165 2 1 12 1 16

NRC (MRN - 

Hornbeck) 

Energy 6503

NRC

800-899-4673 Fourchon, LA N/A 65,145 Fourchon, LA 165 2 1

12 1 16

NRC (MRN - 

Hornbeck) 

Energy 6502

NRC

800-899-4673 Fourchon, LA N/A 64,317 Fourchon, LA 165 2 1 12 1 16

NRC (MRN - 

Hornbeck) 

Energy 6501

NRC

800-899-4673 Fourchon, LA N/A 63,875 Fourchon, LA 165 2 1

GB 386 (Exploratory) WCD

Sample Offshore On-Water Recovery Activation List

Response Times (Hours)

Distance to

Site from Staging 

(Miles)

Skimming 

System

Supplier 

& Phone Warehouse

Est. Derated 

Recovery Capacity 

(EDRC in 

Bbls/Day) 

Storage (Barrels)

Staging Area

Skimming Package

Quantity

3,770 200 165 2.5 1 Fourchon, 

LA 12 1 16.5

12 1 16.5

SOS System 

RM/AW-329

NRC 

800-899-4672

Morgan City, 

LA 8,352 124 Fourchon, LA 165 3 1

Fast Response 

Unit "FRU"

CGA

888-CGA2007Houma, LA

17.5 SOS System 

AB/AW-363

NRC 

800-899-4672

Belle Chasse, 

LA 30,857 124 Fourchon, LA 165 3.5 1

NRC "Energy" 

Vessel

NRC 

800-899-4672

Morgan City, 

LA 1,509 300 Morgan City, 

LA 165 2 1

165 2.5 1

12 1 16

Fast Response 

Unit "FRU"

CGA

888-CGA2007Houma, LA 3,770 200 Fourchon, 

LA

Fast Response 

Unit "FRU"

CGA

888-CGA2007

Belle Chasse, 

LA 3,770 100 Fourchon, LA 165 3.5 1

12 1 17

12 1 17.5

12 1

FOR PUBLIC RELEASE
© The Response Group 2/23/2012 Staging ETA Loadout Time ETA to Site Deployment Time

Total ETA

 

GB 386 (Exploratory) WCD

Sample Offshore On-Water Recovery Activation List

Response Times (Hours)

Distance to

Site from Staging 

(Miles)

Skimming 

System

Supplier 

& Phone Warehouse

Est. Derated 

Recovery Capacity 

(EDRC in 

Bbls/Day) 

Storage (Barrels)

Staging Area

Skimming Package

Quantity

Vikoma Skimmer 1

21" Boom 200'

Personnel 4

Marine Tank 1

* 110' Utility Boat 1

Offshore Skimmer 1

42" Boom 2200'

Personnel 6

110' Utility Boat 1

Deployment Boat 1

Offshore Skimmer 1

36" Expandi Boom 720'

Personnel 4

* 110' Utility Boat 1

Crew Boat 1

Offshore Skimmer 1

36" Expandi Boom 720'

Personnel 4

* 110' Utility Boat 1

Crew Boat 1

Portable Tank 1 200

Offshore Skimmer 1

36" Expandi Boom 720'

Personnel 4

* 110' Utility Boat 1

Crew Boat 1

Portable Tank 1 200

Rope Mop/VTU Skimmer 1

21" Boom 300'

Personnel 4

Marine Tank 1

* 110' Utility Boat 1

Vikoma/VTU Skimmer 1

18" - 21" Boom 200'

Personnel 4

Marine Tank 1

* 110' Utility Boat 1

Vikoma/VTU Skimmer 1

18" - 21" Boom 200'

Personnel 4

Marine Tank 1

* 110' Utility Boat 1

Acme/VTU Skimmer 1

18' - 21" Boom 100'

Personnel 4

Marine Tank 1

* 110' Utility Boat 1

SOS System FF332NRC 

800-899-4672

Belle Chasse, 

LA 3,154 100 Fourchon, LA 165 3.5 1

SOS System RM326NRC 

800-899-4672 Mobile, AL 8,352 124 Fourchon, 

LA 165 6 1

10,011 124 Fourchon, 

LA 165 6 1

SOS System 

WS/AW-328

NRC 

800-899-4672 Sulphur, LA 12,322 124 Fourchon, 

LA 165 6 1

14 1 18 NRC "ADMIRAL" 

OSRV

NRC

800-899-4672 Galveston, TX 26,125 300 Galveston, TX 198 2 1

SOS System 

FF/AW-362

NRC 

800-899-4672 Sulphur, LA

SOS System AW351

NRC 

800-899-4672

Port Arthur, 

TX 6,857 124 Fourchon, LA

12 1 17.5

165 4 1

165 7 1 12 1 21

12 1 20

12 1 20

12 1 20

165 4 1

12 1 18

12 1 18

MOSS Unit w/ 

WP-4

AMPOL

800-482-6765

New Iberia, 

LA 3,565 50 Fourchon, LA

12 1 18 MOSS Unit w/ 

WP-4

AMPOL

800-482-6765

New Iberia, 

LA 3,565 Fourchon, LA

MOSS Unit w/ 

WP-4

AMPOL

800-482-6765

New Iberia, 

LA 3,565 Fourchon, LA 165 4 1

FOR PUBLIC RELEASE
© The Response Group 2/23/2012 Staging ETA Loadout Time ETA to Site Deployment Time

Total ETA

 

GB 386 (Exploratory) WCD

Sample Offshore On-Water Recovery Activation List

Response Times (Hours)

Distance to

Site from Staging 

(Miles)

Skimming 

System

Supplier 

& Phone Warehouse

Est. Derated 

Recovery Capacity 

(EDRC in 

Bbls/Day) 

Storage (Barrels)

Staging Area

Skimming Package

Quantity

15m rigid skimming arm 2

Personnel 4

* Offshore vessel (>165') 1

30T crane 1

500 bbl Portable tank 4 2,000

15m rigid skimming arm 2

Personnel 4

* Offshore vessel (>165') 1

30T crane 1

500 bbl Portable tank 4 2,000

Belt Skimmer 1

67" Sea Sentry 2640'

Personnel 8

Tug - 1,200 HP 2

Tug - 1,800 HP 1

Offshore Barge 1

Personnel 4

* Offshore Tug 1

Offshore Barge 1

Personnel 4

* Offshore Tug 1

Offshore Skimmer 2

42" Boom 1000'

Personnel 6

198' Barge 1

20' Deployment Boat 1

* Offshore Tugs 2

12 1 23 Koseq Skimming 

Arms (2)

CGA

888-CGA2007Galveston, TX 17,829 0 Fourchon, 

LA 165 9 1

22.5 1 26.5

CTCo-2606 

Offshore Barge

CGA

888-CGA2007

Houma, LA N/A 24,000 Houma, LA 182 2 1 22.5 1 26.5

CTCo-5001 

Offshore Barge

CGA

888-CGA2007

Houma, LA N/A 45,000 Houma, LA 182 2 1

DERATED RECOVERY RATE (BBLS/DAY)

TOTAL STORAGE CAPACITY INCLUDING SKIMMING VESSELS (BARRELS) 289,531

236,158

NRC 

"DEFENDER" 

OSRB

NRC

800-899-4672 Mobile, AL 29,465 16,500 Mobile, AL 347 2 1

* - These components are additional operational requirements that must be procured by OSROs in addition to the system identified.

38.5 1 42.5

12 1 23 Koseq Skimming 

Arms (1)

CGA

888-CGA2007Galveston, TX 17,829 0 Fourchon, 

LA 165 9 1

22.5 1 26.5 CGA-200 HOSS 

Barge (OSRB)

CGA

888-CGA2007Houma, LA 43,000 4,000 Houma, LA 182 2 1

FOR PUBLIC RELEASE
© The Response Group 2/23/2012 Staging ETA Loadout Time ETA to Projected Nearshore Operations Deployment Time

Total ETA

Lori Brush Skimmer 1

56" Boom 50'

46' Vessel 1

Personnel 4

Marco Belt Skimmer 1

18" Boom (contractor) 100'

Personnel 3

36' Skimming Vessel 1

Shallow Water Barge 1 249

Marco Belt Skimmer 1

18" Boom (contractor) 100'

Personnel 3

38' Skimming Vessel 1

Belt Skimmer 1

18" Boom 100'

Personnel 3

38' Skimming Vessel 1

Shallow Water Barge 1 249

Lori Brush Skimmer 1

56" Boom 50'

46' Vessel 1

Personnel 4

Marco Belt Skimmer 1

18" Boom (contractor) 100'

Personnel 3

34' Skimming Vessel 1

Shallow Water Barge 1 249

Weir Disc Skimmer 1

18"-21" Boom 200'

Personnel 4

Portable Barge Set * 1

Egmopol Belt Skimmer 1

18" Boom 100'

Personnel 3

34' Skimming Vessel 1

Shallow Water Barge 1 249

Lori Brush Skimmer 1

56" Boom 50'

46' Vessel 1

Personnel 4

Weir Disc Skimmer 1

18"-21" Boom * 200'

Personnel 4

Portable Barge Set 1

Lori Brush Skimmer 1

56" Boom 50'

46' Vessel 1

Personnel 4

GB 386 (Exploratory) WCD

Sample Nearshore On-Water Recovery Activation List

System Supplier 

& Phone Warehouse Package

Quantity

Est. Derated 

Recovery Capacity 

(EDRC in Bbls/Day) 

Storage (Barrels)

Staging Area

Distance to

Project Nearshore 

Operations (Miles)

Response Times (Hours)

DERATED RECOVERY RATE (BBLS/DAY) 11,371

SKIMMING VESSEL STORAGE CAPACITY (BARRELS) 368

* - These components are additional operational requirements that must be procured by OSROs in addition to the system identified.

12 8 1 1 1 11 NRC Weir Disc 

103

NRC 

800-899-4672 Houston, TX 1,371 238 Cameron, 

LA

12 13 1 1 1 16 NRC Weir Disc 

108

NRC

800-899-4672

Corpus 

Christi, TX 1,371 238 Cameron, LA

93 1 0

175 1 0

12 6 1

12 9 1

6.5 1 8.5 CGA 58 

Timbalier Bay

CGA

888-CGA2007Galveston, TX 5,000 65 Galveston, 

TX

M/V Bastian Bay 41 1 0 3 1 5

CGA

888-CGA2007

Lake Charles, 

LA 5,000 65 Lake Charles, LA

12.5 0.5 14 M/V RW 

Armstrong

CGA

888-CGA2007Houma, LA 5,000 65 Houma, LA

M/V Grand Bay 273 1 0 19.5 1 21.5

CGA

888-CGA2007Venice, LA 5,000 65 Venice, LA

1.5 1 9.5

CGA-51 MARCO 

Shallow Water 

Skimmer

CGA

888-CGA2007

Lake Charles, 

LA 3,588 20 Cameron, LA

12 3 1 1.5 1 6.5

CGA-52 MARCO 

Shallow Water 

Skimmer

CGA

888-CGA2007Venice, LA 3,588 34 Cameron, 

LA

12 3 1 1.5 1 6.5

CGA-53 MARCO 

Shallow Water 

Skimmer

CGA

888-CGA2007Houma, LA 3,588 34 Cameron, 

LA

12 3 1 1.5 1 6.5

CGA-54 

Egmopol Shallow 

Water Skimmer

CGA

888-CGA2007Houma, LA 3,000 90 Cameron, 

LA

1.5 1 12.5

CGA-55 

Egmopol Shallow 

Water Skimmer

CGA

888-CGA2007

Galveston, TX 3,000 90 Cameron, 

LA

FOR PUBLIC RELEASE
© The Response Group 2/23/2012 Staging ETA Loadout Time ETA to Site Deployment Time

Total ETA

* Offshore Firefighting Vessels 2

* Cranes 2

* Roll-off Boxes 2

Personnel 8

* Air Monitoring Equipment 2

* Air Monitoring Equipment 1

* Offshore Vessel 1

Personnel 4

* Air Monitoring Equipment 1

* Offshore Vessel 1

Personnel 4

Fixed Wing Aircraft 1

Trained ISB Spotter 2

ISB Documenter 1

Fire Boom (ft) 500

Guide Boom/Tow Line (ft) 400

* Offshore Vessel (0.5 kt capability) 2

Personnel 6

Ignition Device 10

Fire Boom (ft) 500

Guide Boom/Tow Line (ft) 400

* Offshore Vessel (0.5 kt capability) 2

Personnel 6

Ignition Device 10

Fire Boom (ft) 500

Guide Boom/Tow Line (ft) 400

* Offshore Vessel (0.5 kt capability) 2

Personnel 6

Ignition Device 10

* Air Monitoring Equipment 1

* Offshore Vessel 1

Personnel 4

Warehouse In-Situ Burn Package

TBD TBD

12 1

Fourchon, 

LA 165 TBD 1 12 1

20

ISB Fire-Fighting 

Team TBD TBD Fourchon, LA 165 TBD 1 12

Wildlife 

Monitoring Team

TBD

USCG Mobile, AL Fourchon, 

LA 165

TBD

Aerial Spotting 

Team (per 2 ISB 

Task Forces)

TBD

Fire Team 

(In-Situ Burn

Fire System)

ISB Fire Team 

(In-Situ Burn

Fire System)

NRC 

800-899-4672

NRC 

800-899-4672

SMART In-Situ 

Burn Monitoring 

Team

12 1

1 Fourchon, 

LA

NRC 

800-899-4672

Morgan City, 

LA

12 1

TBD

Fourchon, 

LA 165

Fourchon, 

LA 165 TBD 1 12 1

12 1

3

Morgan City, 

LA

Morgan City, 

LA

1

1

Fourchon, 

LA 165 3

* - These components are additional operational requirements that must be procured by OSROs in addition to the system identified.

TOTAL FIRE BOOM AVAILABLE (FEET) 1,500

GB 386 (Exploratory) WCD

Sample In-Situ Burn Equipment Activation List

6 1

165 3 1 12

TBD

17

17

17

Fire Team 

(In-Situ Burn

Fire System)

Safety 

Monitoring Team TBD TBD Fourchon, LA 165 TBD 1

1 TBD

Quantity

Staging Area

Distance to

Site from 

Staging (Miles)

Response Times (Hours)

In-Situ Burn 

System

Supplier 

& Phone

FOR PUBLIC RELEASE
Staging ETA

Loadout 

Time

ETA to Site

Deployment 

Time

Total ETA

Multi-Service Vessel 1

Multi-Service Vessel 1

ROV's 2

Coil Tubing Unit 1

Dispersant 200,000 gal

Manifold 1

System 1

Vessel 1

ROV's 2

Multi-Purpose Supply Vessel 1

Drill Ship (Processing Vessel) 1

"Top Hat" 1

Containment Chamber 1

Shuttle Barge 1

Anchor Handling Tug Supply 

Vessel 1

ROV's 1

Hydraulic System 1

Capping Stack 1

* - Response time may vary depending on Drill Ship's operations and location at the time of deployment.

2 1.5 12 3 18.5

Houston, TX

Capping Stack RP / 

MWCC

Fourchon, LA

Fourchon, 

LA 165

1.5 12 2 17

Houston, TX

1 12 3 18

Subsea Dispersant 

Application

RP / 

MWCC

Fourchon, LA

Fourchon, 

LA 165 1.5

"Top Hat" Unit RP / 

MWCC Fourchon, LA Fourchon, 

LA 165 13*

1.5 12 0.5 14 ROV's 2 0 Site Assessment and 

Surveillance RP Fourchon, LA Fourchon, LA 165

GB 386 (Exploratory) WCD

Control and Containment Activation List

Containment System Supplier 

& Phone Warehouse Package

Quantity

Staging Area

Distance to

Site from 

Staging (Miles)

Response Times (Days)

FOR PUBLIC RELEASE
© The Response Group 2/23/2012 Staging ETA Loadout Time ETA to Site Deployment Time Total ETA

Dispersant Spray System 1

Dispersant (Gallons) 500

Personnel 4

* 110' Utility Boat 1

* Crew Boat 1

Dispersant Spray System 1

Dispersant (Gallons) 500

Personnel 4

* Crew Boat 1

Dispersant Spray System 1

Dispersant (Gallons) 500

Personnel 4

* 110' Utility Boat 1

* Crew Boat 1

Personnel 4

* Crew Boat 1

Dispersant Spray System 1

Dispersant (Gallons) 500

Personnel 4

* Crew Boat 1

Dispersant Spray System 1

Dispersant (Gallons) 500

Personnel 4

* Crew Boat 1

61.5

USCG Mobile, AL Fourchon, 

LA

Warehouse Boat Spray Dispersant 

Package

165 AMPOL

800-482-6765

Vessel Based 

Dispersant 

Spray System

39.5

Vessel Based 

Dispersant 

Spray System

NRC

800-899-4672

0.5

Fire Monitor 

Induction 

Dispersant 

Spray System

Fire Monitor 

Induction 

Dispersant 

Spray System

AMPOL

800-482-6765 Cameron, LA Fourchon, LA

Fourchon, 

LA 165

165 5.5 1 19

NRC

800-899-4672 165 26 0.5 12

Fourchon, LA 12 Fourchon, 

LA

1 12

3

Clermont, NJ Fourchon, 

LA

* - These components are additional operational requirements that must be procured by OSROs in addition to the system identified.

14.5

Response Times (Hours)

Quantity

Staging Area

Distance to

Site from 

Staging 

(Miles)

1

165 6 19.5

16.5

Vessel Based 

Dispersant 

Spray System

Boat Spray 

Dispersant 

System

Supplier 

& Phone

USCG SMART 

Team 0.5

1

12

1

0.5

12

0.5

1

GB 386 (Exploratory) WCD

Sample Offshore Boat Spray Dispersant Activation List

Seattle, WA Fourchon, 

LA 165 48 0.5 12 1

NRC

800-899-4672 Morgan City, LA

FOR PUBLIC RELEASE
Staging ETA

Loadout 

Time

ETA to Site

Total ETA

Surveillance Aircraft 1

Spotter Personnel 2

Crew - Pilots 1

Surveillance Aircraft 1

Spotter Personnel 2

Crew - Pilots 1

Surveillance Aircraft 1

Spotter Personnel 2

Crew - Pilots 1

Surveillance Aircraft 1

Spotter Personnel 2

Crew - Pilots 1

0.58 2.00

0.25 0.58 2.00

Sikorsky S-76 

Helicopter

Air Speed -

141 knots

PHI

985-475-5400 Houma, LA Houma, LA 168 2 0.25

Eurocopter EC135 Helicopter

Air Speed -

141 knots

PHI

985-475-5400 Houma, LA Houma, LA 168 2

0.58 2.00

0.25 0.58 2.00

Aero 

Commander

Air Speed - 288 

MPH

Airborne 

Support

985-851-6391

Houma, LA Houma, 

LA 168 2 0.25

Aero 

Commander

Air Speed - 288 

MPH

Airborne 

Support

985-851-6391

Houma, LA Houma, 

LA 168 2

Aerial 

Surveillance 

System

Supplier 

& Phone Warehouse Aerial Surveillance Package

Quantity

Staging Area

Distance to Site 

from Staging 

(nautical miles)

Response Times (Hours)

GB 386 (Exploratory) WCD

Sample Aerial Surveillance Activation List

FOR PUBLIC RELEASE
© The Response Group 2/23/2012 Staging ETA Loadout Time ETA to Site Deployment Time Total ETA

Aero Commander 1

Spotter Personnel 2

Crew - Pilots 1

DC-3 Dispersant Aircraft 1

Dispersant - Gallons 2000

Spotter Aircraft 1

Spotter Personnel 2

Crew - Pilots 2

DC-3 Dispersant Aircraft 1

Dispersant - Gallons 1200

Spotter Aircraft 1

Spotter Personnel 2

Crew - Pilots 2

DC-3 Dispersant Aircraft 1

Dispersant - Gallons 1200

Spotter Aircraft 1

Spotter Personnel 2

Crew - Pilots 2

C-130 Aircraft (contractor) 1 27.3

ADDS PACK 1 to

Dispersant - Gallons 5000 51.3

Spotter Aircraft 1

Spotter Personnel 2

Crew - Pilots 2

L-382 Hercules Aircraft 1 9.3

ADDS PACK 1 to

Dispersant - Gallons 5000 29.3

Spotter Aircraft 1

Spotter Personnel 2

Crew - Pilots 2

L-382 Hercules Aircraft 1 9.3

ADDS PACK 1 to

Dispersant - Gallons 5000 29.3

Spotter Aircraft 1

Spotter Personnel 2

Crew - Pilots 2

3.95

Houma, LA

2nd Flight 168 1.12 0.5 1.12 0.3 3.05

Houma, LA

1st Flight 168

Airborne 

Support

985-851-6391

Houma, LA

1.78 0.5

Houma, LA

1st Flight 168 2 0.5 0.87 0.3

Houma, LA

2nd Flight 168 0.87 0.5 0.87 0.3

Houma, LA

1st Flight 168 2

1.12 0.3

3.95

3.05

256 0.78 0.3 0.78 0.5

Stennis

INTL, MS

2nd Flight

0.5

0.5 1.12 0.3

Houma, LA

2nd Flight 168 1.12 0.5 1.12 0.3

2.35

2.35

Stennis

INTL, MS

2nd Flight

256 0.78

Stennis

INTL, MS

1st Flight

256 6-24 2-4 0.78 0.5

ADDS PACK

Air Speed - 330 

MPH

Clean 

Carribean

985-851-6391

Pt. Everglades, 

FL

2.35

ADDS PACK

Air Speed - 330 

MPH

Oil Spill 

Response

+44 (0) 1224-

72-6859

Singapore, SG

ADDS PACK

Air Speed - 330 

MPH

0.3 0.78 0.5

Oil Spill 

Response

+44 (0) 1224-

72-6859

South 

Hampton, UK

Clearwater, 

FL

1st Flight

586 24-48 1

Aerial 

Dispersant 

System

Supplier 

& Phone

Distance to

Site from 

Staging (Miles)

Response Times (Hours)

Quantity

Staging Area

Warehouse Aerial Dispersant 

Package

Houma, LA

BT-67 (DC-3 

Turboprop) 

Aircraft

Air Speed - 194 

MPH

Houma, LA Houma, LA 168 2 0.4 0.58 0.2

Aero 

Commander

Air Speed - 288 

MPH

Airborne 

Support

985-851-6391

Airborne 

Support

985-851-6391

Houma, LA

2.55

2 0.5

3.70

3.20

DC-3 Aircraft

Air Speed - 150 

MPH

DC-3 Aircraft

Air Speed - 150 

MPH

Airborne 

Support

985-851-6391

GB 386 (Exploratory) WCD

Sample Offshore Aerial Dispersant Activation List

2-4 0.78 0.5

256 0.78 0.3 0.78

Stennis

INTL, MS

2nd Flight

Stennis

INTL, MS

1st Flight

256 6-24

FOR PUBLIC RELEASE
GARDEN BANKS 386

OSRAM TABLE

Trajectory of a spill and the probability of it impacting a land segment have been projected 

utilizing Hess Corporation’s WCD and information in the BSEE Oil Spill Risk Analysis 

Model (OSRAM) for the Central and Western Gulf of Mexico available on the BSEE

website using 30 day impact. The results are tabulated below.

Area/Block OCS-G Launch

Area Land Segment Contact 10 Day 30 Day

Garden Banks 

386 20

Kleberg, TX - 1

Nueces, TX - 1

Aransas, TX - 1

Calhoun, TX - 1

Matagorda, TX - 3

Brazoria, TX - 2

Galveston, TX - 6

Jefferson, TX - 4

Cameron, LA 1 9

Vermilion, LA - 3

Iberia, LA - 1

Terrebonne, LA - 2

Plaquemines, LA - 1

FOR PUBLIC RELEASE
Spill Scenario - Oil Budget Table ADIOS® 2.0

Oil Name = ANAHUAC

API = 33.2 Pour Point = less than -15 deg C

Wind Speed = constant at 15 knotsWave Height = computed from winds

Water temperature = 75 deg F

Time of Initial Release = February 23, 0800 hours

Total amount of Oil Released = 127984 bbl

-------------------------------------------------------------------

Hours Into Released Evaporated Dispersed Remaining 

 Spill bbl percent percent percent 

 1 127,984 - 0 - 0 - 100 

 2 127,984 2 0 98 

 4 127,984 - 6 - 1 - 94 

 6 127,984 9 1 90 

 8 127,984 - 12 - 2 - 86 

 10 127,984 14 3 84 

 12 127,984 - 15 - 3 - 82 

 18 127,984 19 4 77 

 24 127,984 - 21 - 4 - 75 

 30 127,984 22 4 74 

 36 127,984 - 23 - 4 - 73 

 42 127,984 24 4 72 

 48 127,984 - 25 - 4 - 71 

 54 127,984 26 4 70 

 60 127,984 - 26 - 4 - 69 

 66 127,984 27 4 69 

 72 127,984 - 27 - 4 - 68 

 78 127,984 28 4 68 

 84 127,984 - 28 - 4 - 67 

 90 127,984 29 4 67 

 96 127,984 - 29 - 4 - 67 

 102 127,984 30 4 66 

 108 127,984 - 30 - 4 - 66 

 114 127,984 30 4 66 

 120 127,984 - 31 - 4 - 65 

February 23, 2012

FOR PUBLIC RELEASE
Hess Corporation    Llano Field  

Supplemental EP    Garden Banks Block 386, OCS‐G10350

Appendix J

Environmental Monitoring Information  

(a) Monitoring Systems

   

Hess subscribes to Impact Weather Service which provides access to real time weather

conditions, and provides periodic updates on impending inclement weather conditions such as

tropical depressions, storms and/or hurricanes entering the Gulf of Mexico.

Hess also relies on the National Weather Service to support the aforementioned subscribed

service. During impending inclement weather conditions, Hess closely coordinates the activity

with our contractors and field personnel to ensure the safety of people for evacuations to

ensure protection of the environment and the facility/equipment.

Garden Banks 386 is in water depths greater than 300 meters (984 feet); therefore, Hess will

follow the guidelines of the applicable Notice to Lessees NTL 2009‐G02 by monitoring and

gathering ocean current data using Acoustic Doppler Current Profile (ADCP) while the MODU is

on location.

(b) Incidental Takes

There is no reason to believe that any protected species listed under the ESA or MMPA may be

incidentally taken by the activities proposed under this EP.  Hess Corporation will comply with

NTL 2012‐JOINT‐G01 “Vessel Strike Avoidance and Injured/Dead Protected Species Reporting,”

NTL 2012‐JOINT‐GO2 "Implementation of Seismic Survey Mitigation Measures and Protected

Species Observer Program" and NTL 2012‐BSEE‐GO1 “Marine Trash and Debris Awareness and

Elimination.”

FOR PUBLIC RELEASE
Hess Corporation    Llano Field  

Supplemental EP    Garden Banks Block 386, OCS‐G10350

Appendix K

Lease Stipulations Information

Lease stipulations are developed and implemented for each lease sale and included within the

Environmental Impact Statement (EIS) prepared for same, thus becoming part of the oil and gas lease

terms and thereby enforceable as part of that lease.  

As part of the Final Notice of Sale prepared for the Western Gulf of Mexico Oil and Gas Lease Sale 115,

the Archaeological Resource Stipulation was imposed on Garden Banks Block 386, OCS‐G10350. The

stipulation has since become converted to operational regulations under 30 CFR 550.194.

Hess Corporation will abide by all terms of the mineral lease.

  

FOR PUBLIC RELEASE
Hess Corporation    Llano Field  

Supplemental EP    Garden Banks Block 386, OCS‐G10350

Appendix L

Environmental Mitigation Measures Information

(a) Description of measures taken to avoid, minimize and mitigate impacts to marine and

coastal environments, habitats, biota and threatened and/or endangered species:

Hess Corporation will implement mitigation measures required by all applicable Federal & State

requirements, including, but not limited to those concerning:  Air emissions, ocean discharges,

solid and liquid waste disposal and internal Hess standards and policies.  Project activities will be

conducted in accordance with the Regional Oil Spill Response Plan (see Appendix I).    The EIA

included under Appendix S, discusses site‐specific impacts and mitigation measures as relative

to activities proposed under this Supplemental Exploration Plan.

(b) Incidental Takes

There is no reason to believe that a protected species may be incidentally taken by the proposed

activities, however, Hess Corporation will adhere to the requirements set forth in the following

documents, as applicable, to avoid or minimize impacts to any of the species listed in the ESA as

a result of the operations proposed to be conducted herein:

NTL 2012‐JOINT‐G01, “Vessel Strike Avoidance and Injured/Dead Protected Species Reporting,”

NTL 2012‐JOINT‐GO2, "Implementation of Seismic Survey Mitigation Measures and Protected

Species Observer Program"  

NTL 2012‐BSEE‐GO1, “Marine Trash and Debris Awareness and   Elimination.”

  

  

FOR PUBLIC RELEASE
Hess Corporation    Llano Field  

Supplemental EP    Garden Banks Block 386, OCS‐G10350

Appendix M

Decommissioning Information

Pursuant to Notice to Lessees No. 2008‐G04, the information at 30 CFR 550.255 regarding

decommissioning is not required to accompany plans proposing activities in the Gulf of Mexico.  

Hess Corporation will abide by the decommissioning regulations set forth in 30 CFR and

associated Notices to Lessees as applicable.

FOR PUBLIC RELEASE
Hess Corporation    Llano Field  

Supplemental EP    Garden Banks Block 386, OCS‐G10350

Appendix N

Related Facilities and Operations Information

There will be no production proposed under this plan, therefore the information under Related Facilities

and Operations Information, Transportation Systems, & Produced Liquid Hydrocarbon Transportation

Vessels is not included under this Supplemental Exploration Plan.

FOR PUBLIC RELEASE
Hess Corporation    Llano Field  

Supplemental EP    Garden Banks Block 386, OCS‐G10350

Appendix O

Support Vessels and Aircraft Information

(a) General

Type Max Fuel Tank Storage

Capacity

Max No. in

Area at Any

Time

Trip Frequency or

Duration

Supply Boats 70,000 USG               2 3 times weekly

Service Boats 70,000 USG               2 Daily

Crew Boats 70,000 USG 1 Weekly

Aircraft   764 USG      1 As needed

(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 feet 70,000 USG 3x  Weekly

From the shorebase in Fourchon, LA to

L&L Fuel Dock, then to Garden Banks

386

(c) Drilling Fluids Transportation

This Supplemental EP does not propose activities that will affect the state of Florida therefore

this section is not applicable in accordance with NTL 2008‐G04.

(d) Solid and Liquid Wastes Transportation

Information regarding solid and liquid wastes transportation is contained within the Water

Quality Tables included under Appendix G (Waste and Discharge Information) attachments.

(e) Vicinity Map

Enclosed as Attachment O‐1 is a vicinity map showing the location of the activities proposed

relative to the shoreline, and the primary route(s) of the support vessels and aircraft that will be

taken when traveling between the onshore support facilities and the vessels in the field.

FOR PUBLIC RELEASE
Hess Corporation    Llano Field  

Supplemental EP    Garden Banks Block 386, OCS‐G10350

Attachment O‐1

Vicinity Map

FOR PUBLIC RELEASE
!(

!(

!(

!(

Atwa

GREEN CANYON

Garden Banks

Vermilion Area

Ship Shoal Area

Eugene Island Area

Ewing Bank

W

Keathley Canyon

Grand Isle

Area

Vermilion Area

South Addition

Ship Shoal Area

South Addition

Eugene Island Area

South Addition

S Timbalier Area

S Addition

South Marsh

Island Area

South Addition

South Marsh

Island Area

South Marsh

Island Area

North Addition

South

Pelto

Area

W

S

Grand Isle Area

S. Addition

East Cameron

Area

Esat Cameron

South Addition

Louisiana

-600

-30 00

-1 500

-60 00

-6000

-6000

-3000

-1500

-1500

-6000

-1500

-3000

-3000

-60 0

-3000

-3000

-60 0

-3000

-6000

-600

-3000

-3000

Fourchon

New Orleans

Morgan City

Golden Meadow

HESS CORPORATION

UNITED STATES OFFSHORE PRODUCTION

GARDEN BANKS AREA

BLOCK 386

OCG-G- 10350

DATE: 12/2011

PUBLIC

GARDEN BANKS

BLOCK 386

OCS-G-10350

Llano_Vicinity.MXD

VICINITY MAP

PROPOSED TRANSPORTATION ROUTE LLANO FIELD

 HELICOPTER

 BOAT

APPROX. 159 MLES TO FOURCHON

APPROX. 130 MILES TO NEAREST SHORE

LEGEND

FOR PUBLIC RELEASE
Hess Corporation    Llano Field  

Supplemental EP    Garden Banks Block 386, OCS‐G10350

Appendix P

Onshore Support Facilities Information

(a) General

The proposed operations in Garden Banks 386 are located approximately 130 miles from the

nearest shoreline and approximately 159 miles from the onshore support bases.

Name Location Existing, New or Modified

Gulf Offshore Logistics Fourchon, LA Existing

Air Logistics Galliano, LA Existing

(b) Support Base Construction or Expansion

Hess Corporation does not propose the construction or expansion of a support base to support

the activities proposed under this plan, therefore this section is not required.

(c) Support Base Construction or Expansion Timetable

Hess Corporation does not propose the construction or expansion of a support base to support

the activities proposed under this plan, therefore this section is not required.

(d) Waste Disposal

Information concerning waste disposal is contained within the Water Quality Tables included

under Appendix G (Waste and Discharge Information) attachments.

FOR PUBLIC RELEASE
Hess Corporation    Llano Field  

Supplemental EP    Garden Banks Block 386, OCS‐G10350

Appendix Q

Sulphur Operations Information

. There is no production involving sulphur operations proposed under this EP, therefore this section is

not required.

FOR PUBLIC RELEASE
Hess Corporation    Llano Field  

Supplemental EP    Garden Banks Block 386, OCS‐G10350

Appendix R

Coastal Zone Management Act Information

Pursuant to the guidance contained in NTL 2008‐G04, a Coastal Zone Management Certification is not

required to be included in Supplemental Plans submitted to the BOEM.  

FOR PUBLIC RELEASE
Environmental Impact Analysis

SUPPLEMENTAL EXPLORATION PLAN

Garden Banks Block 386 (OCS‐G 10350)

Offshore Louisiana

February 2012

Prepared for:

Hess Corporation

1501 McKinney Street

Houston, Texas  77010

Telephone: (713) 496‐5866

Prepared by:

CSA International, Inc.

8502 SW Kansas Avenue

Stuart, Florida  34997

Telephone: (772) 219‐3000

FOR PUBLIC RELEASE
Garden Banks Block 386 February 2012

Environmental Impact Analysis for Supplemental Exploration Plan Page ii

Contents

Page

Introduction ................................................................................................................1

A.  Impact‐Producing Factors .......................................................................................5

A.1 Drilling Rig Presence (including noise and lights).......................................................................... 5

A.2 Physical Disturbance to the Seafloor ............................................................................................ 5

A.3 Air Pollutant Emissions.................................................................................................................. 8

A.4 Effluent Discharges........................................................................................................................ 8

A.5 Water Intake.................................................................................................................................. 8

A.6 Onshore Waste Disposal ............................................................................................................... 8

A.7 Marine Debris................................................................................................................................ 9

A.8 Support Vessel and Helicopter Traffic........................................................................................... 9

A.9 Accidents ....................................................................................................................................... 9

A.9.1 Types of Accidents Evaluated ............................................................................................ 9

A.9.2 Small Fuel Spill................................................................................................................. 10

A.9.3 Crude Oil Spill (Worst Case Discharge)............................................................................ 11

A.9.4 Other Accidents Not Analyzed in Detail .......................................................................... 14

B.  Affected Environment...........................................................................................15

C.  Impact Analysis.....................................................................................................17

C.1 Physical/Chemical Environment.................................................................................................. 17

C.1.1 Air Quality........................................................................................................................ 17

C.1.2 Water Quality .................................................................................................................. 20

C.2 Seafloor Habitats and Biota......................................................................................................... 22

C.2.1 Soft Bottom Benthic Communities.................................................................................. 22

C.2.2 High‐Density Deepwater Benthic Communities.............................................................. 24

C.2.3 Designated Topographic Features................................................................................... 26

C.2.4 Pinnacle Trend Area Live Bottoms................................................................................... 27

C.2.5 Eastern Gulf Live Bottoms ............................................................................................... 27

C.3 Threatened, Endangered, and Protected Species and Critical Habitat....................................... 27

C.3.1 Sperm Whale (Endangered) ............................................................................................ 29

C.3.2 West Indian Manatee (Endangered) ............................................................................... 33

C.3.3 Endangered Mysticete Whales........................................................................................34

C.3.4 Non‐Endangered Marine Mammals (Protected)............................................................. 34

C.3.5 Sea Turtles (Endangered/Threatened) ............................................................................ 37

C.3.6 Piping Plover (Threatened).............................................................................................. 40

C.3.7 Whooping Crane (Endangered) ....................................................................................... 42

C.3.8 Gulf Sturgeon (Threatened)............................................................................................. 42

C.3.9 Smalltooth Sawfish (Endangered) ................................................................................... 43

C.3.10 Beach Mice (Endangered)................................................................................................ 44

C.3.11 Elkhorn Coral (Endangered)............................................................................................. 44

FOR PUBLIC RELEASE
Contents

(Continued)

Page

Garden Banks Block 386 February 2012

Environmental Impact Analysis for Supplemental Exploration Plan Page iii

C.4 Coastal and Marine Birds ............................................................................................................ 45

C.4.1 Marine Birds .................................................................................................................... 45

C.4.2 Shorebirds and Coastal Nesting Birds.............................................................................. 47

C.5 Fisheries Resources ..................................................................................................................... 50

C.5.1 Pelagic Communities and Ichthyoplankton..................................................................... 50

C.5.2 Essential Fish Habitat....................................................................................................... 52

C.6 Archaeological Resources............................................................................................................ 55

C.6.1 Shipwreck Sites................................................................................................................ 55

C.6.2 Prehistoric Archaeological Sites ...................................................................................... 56

C.7 Coastal Habitats and Protected Areas......................................................................................... 57

C.8 Socioeconomic and Other Resources.......................................................................................... 59

C.8.1 Recreational and Commercial Fishing ............................................................................. 59

C.8.2 Public Health and Safety.................................................................................................. 61

C.8.3 Employment and Infrastructure ...................................................................................... 62

C.8.4 Recreation and Tourism ..................................................................................................63

C.8.5 Land Use .......................................................................................................................... 64

C.8.6 Other Marine Uses .......................................................................................................... 64

D.  Environmental Hazards.........................................................................................65

D.1 Geologic Hazards......................................................................................................................... 65

D.2 Severe Weather........................................................................................................................... 65

D.3 Currents and Waves .................................................................................................................... 65

E.  Alternatives ..........................................................................................................65

F.  Mitigation Measures .............................................................................................65

G.  Consultation.........................................................................................................66

H.  Preparers..............................................................................................................66

I.  References.............................................................................................................66

FOR PUBLIC RELEASE
Garden Banks Block 386 February 2012

Environmental Impact Analysis for Supplementall Exploration Plan Page iv

List of Tables

Table Page

1 Notices to Lessees and Operators (NTLs) applicable to this Environmental Impact

Analysis (EIA) ......................................................................................................................... 3

2 Matrix of impact‐producing factors and affected environmental resources........................ 6

3 Conditional probabilities expressed as percentage chance that an oil spill starting

at Launch Point 3 will contact a certain parish, county, or coastline within

120 days............................................................................................................................... 12

4 Estimated air pollutant emissions in Garden Banks Block 386 over the life of the

project ................................................................................................................................. 19

5 Benthic community data from stations near the lease area and in similar water

depths sampled during the Northern Gulf of Mexico Continental Slope Habitats

and Benthic Ecology Study (From: Rowe and Kennicutt, 2009).......................................... 22

6 Federally listed endangered and threatened species potentially occurring in the

lease area and along the northern Gulf of Mexico coast.................................................... 28

7 Wildlife refuges, wilderness areas, and State and National parks within the

geographic range of the potential shoreline contacts after 120 days ................................ 57

List of Figures

Figure Page

1 Distance of lease area from nearest shoreline (Louisiana), onshore support base

at Port Fourchon, and helicopter base at Galliano, Louisiana .............................................. 2

2 Bathymetric map of the lease area showing surface hole locations of proposed

Wells LL4, LL5, and LL6 ........................................................................................................ 16

3 Location of selected environmental features in relation to the lease area........................ 41

FOR PUBLIC RELEASE
Garden Banks Block 386 February 2012

Environmental Impact Analysis for Supplementall Exploration Plan Page v

Acronyms and Abbreviations

ADIOS Automated Data Inquiry for Oil Spills

bbl barrel

BHL bottom hole location

BOEM Bureau of Ocean Energy Management

BOEMRE Bureau of Ocean Energy Management,

Regulation and Enforcement  

BOP blowout preventer

B.P. Before Present

BSEE Bureau of Safety and Environmental

Enforcement

CEI Coastal Environments, Inc.

CFR Code of Federal Regulations

CGA Clean Gulf Associates

CH4 methane

CO carbon monoxide

CO2 carbon dioxide

DOCD Development Operations Coordination

Document

DP dynamically positioned

DPP Development and Production Plan

EEZ Exclusive Economic Zone

EFH Essential Fish Habitat

EIA Environmental Impact Analysis

EIS Environmental Impact Statement

EP Exploration Plan

ESA Endangered Species Act

FAD fish‐attracting device

FR Federal Register

GB Garden Banks

GEMS Geoscience Earth & Marine Services, Inc.

GMFMC Gulf of Mexico Fishery Management

Council

GPS global positioning system

H2S hydrogen sulfide

HAPC Habitat Area of Particular Concern

HAZWOPER Hazardous Waste Operations and

Emergency Response

Hess Hess Corporation

ICN Independent Contractors Network

IPF impact‐producing factor

MARPOL International Convention for the

Prevention of Pollution from Ships

MMC Marine Mammal Commission

MMPA Marine Mammal Protection Act

MMS Minerals Management Service

MP Main Pass

MRN Marine Resource Network

MSRC Marine Spill Response Corporation

NAAQS National Ambient Air Quality Standards

NMFS National Marine Fisheries Service

NOAA National Oceanic and Atmospheric

Administration

NO2 nitrogen dioxide

NOx nitrogen oxides  

NPDES National Pollutant Discharge Elimination

System

NPS National Park Service

NRC National Research Council

NRDA Natural Resource Damage Assessment

NTL Notice to Lessees and Operators

NWR National Wildlife Refuge

OBM oil‐based mud

OCS Outer Continental Shelf

OSAT Operational Scientific Advisory Team

OSRA Oil Spill Risk Analysis

OSRO Oil Spill Removal Organization

OSRP Oil Spill Response Plan

PAH polycyclic aromatic hydrocarbon

PM particulate matter

PSD Prevention of Significant Deterioration

SBF synthetic‐based fluid

SBM synthetic‐based mud

SEP Supplemental Exploration Plan

SHL surface hole location

SOx sulfur oxides

SWSS Sperm Whale Seismic Study

USCG U.S. Coast Guard

USEPA U.S. Environmental Protection Agency

USFWS U.S. Fish and Wildlife Service

VOC volatile organic compound

WCD worst case discharge

FOR PUBLIC RELEASE
Garden Banks Block 386 February 2012

Environmental Impact Analysis for Supplemental Exploration Plan Page 1

Introduction

Hess Corporation (Hess) is submitting a Supplemental Exploration Plan (SEP) for Garden Banks

Block 386 (GB 386).  The SEP includes the drilling, completion, and temporary abandonment of

four exploration wells (LL4, LL5, LL5 sidetrack, and LL6) beginning in 2012 and ending in 2014.  

Water depth at the wellsites is approximately 2,623 ft (800 m).  All surface hole locations (SHLs)

and bottom hole locations (BHLs) will be in GB 386.  It is anticipated to take approximately 200

days to drill wells LL4 and LL6, and 240 days to drill LL5.    The Atwood Condor, a dynamically

positioned (DP) semisubmersible rig or an equivalent rig, will be used for drilling the four wells.  

The lease area is located 130 miles (209 km) south‐southwest of the nearest shoreline

(Louisiana), 159 miles (256 km) from the onshore support base at Port Fourchon, Louisiana, and

174 miles (280 km) from the helicopter base at Galliano, Louisiana (Figure 1).   

This Environmental Impact Assessment (EIA) is a project‐ and site‐specific analysis of Hess’s

planned activities and has been prepared for submittal to the Bureau of Ocean Energy

Management (BOEM1

) in accordance with applicable regulations, including 30 Code of Federal

Regulations (CFR) 550.212(o) and 550.227.    As specified in Notice to Lessees and Operators

(NTL) 2008‐G04, an EIA is a project‐specific analysis that focuses on the impacts of a specific plan

to the extent feasible.    Potential impacts have been analyzed at a broader level in the

Programmatic Environmental Impact Statement (EIS) for the Outer Continental Shelf (OCS) Oil

and Gas Leasing Program (MMS, 2007a) and in lease sale EISs for the Western and Central Gulf

of Mexico Planning Areas (MMS, 2007b, 2008); the analyses from those documents are

incorporated here by reference.   Updated environmental baseline information relative to the

Macondo incident presented in the Final Supplemental EIS for Central Planning Area Lease Sale

216/222 (BOEM, 2012) and the Final Supplemental EIS for Western Planning Area Lease Sale 218

(BOEM, 2011) has also been incorporated.

Statistics from offshore drilling in the U.S. Gulf of Mexico provide a reasonable basis for

evaluating oil spill risk during exploratory drilling.    According to Holand (1997), the average

frequency of a loss of well control incident or “blowout” during exploratory drilling in the

U.S. Gulf of Mexico is 0.00593 blowouts per well drilled, or one blowout per 169 exploration

wells drilled.    Similarly, the MMS Safety and Environmental Management Program blowout

incident rate for 1996 to 1999 was approximately five blowouts per 1,000 well starts, or one

blowout per 200 well starts (MMS, 2000).  More recently in its Final Supplemental EIS for the

Central Gulf of Mexico Planning Area, BOEM confirmed that “significant changes to the spill

rates for the entire OCS are not anticipated” (BOEM, 2012).

Historically, most blowouts have not resulted in oil spills.  Of the 151 well blowouts in the Gulf of

Mexico from 1971 to 1995, only 18 (12%) resulted in oil spills, with a total combined volume of

1,000 barrels (bbl) of crude oil and condensate released (MMS, 2000).  Between 1964 and 1999,

almost all offshore spills (94%) from drilling and production‐related operations on the OCS were

less than or equal to 1 bbl in size (Anderson and LaBelle, 2000).  According to BOEMRE’s Interim

Final Drilling Safety Rule (75 Federal Register [FR] 63365 dated 10 October 2010) issued

following the Macondo incident, the baseline risk of a catastrophic blowout is estimated to be

about once every 26 years.

                                                           

1 On 1 October 2011, the Bureau of Ocean Energy Management, Regulation and Enforcement (BOEMRE), formerly the

Minerals Management Service (MMS), was replaced by the BOEM and the Bureau of Safety and Environmental Enforcement

(BSEE) as part of a major reorganization.

FOR PUBLIC RELEASE
Garden Banks Block 386 

Environmental Impact Analysis for Supplemental Exploration Plan 

Figure 1. Distance of lease area from nearest shoreline (Louisiana), onshore support base at Port Fourchon, and helic

Louisiana.

FOR PUBLIC RELEASE
Garden Banks Block 386 February 2012

Environmental Impact Analysis for Supplemental Exploration Plan Page 3

Hess’s Regional Oil Spill Response Plan (OSRP) was approved by the BOEMRE in March 2010,

modified in October 2010, and certified on January 2011.  On March 9, 2012 Hess Corporation

submitted an update to the Regional OSRP to include the worst case discharge volume proposed

under this plan.  The Regional OSRP details Hess’s plan for response to rapidly and effectively

manage oil spills that may result from drilling and production operations.  Hess has designed its

response program based on a regional capability of response to spills ranging from small

operational spills to a worst discharge (WCD) from a well blowout.    Hess’s spill response

program meets the response planning requirements of the relevant coastal states and

applicable Federal oil spill planning regulations and also includes information regarding Hess’s

regional oil spill organization and dedicated response assets, potential spill risks, and local

environmental sensitivities.    The OSRP describes personnel and equipment mobilization, the

incident management team organization, and an overview of actions and notifications to be

taken in the event of a spill.  All activities planned for GB 386 are covered under the Regional

OSRP in accordance with 30 CFR 254.

This EIA is organized into Sections A through I corresponding to the information required by

NTL 2008‐G04.    The main impact‐related discussions are in Sections A (Impact‐Producing

Factors) and C (Impact Analysis). Table 1 lists and summarizes the NTLs that are applicable to

this EIA.

Table 1. Notices to Lessees and Operators (NTLs) applicable to this Environmental Impact

Analysis (EIA).

NTL Title Summary

2012‐JOINT‐G01

Vessel Strike Avoidance and

Injured/Dead Protected Species

Reporting

Recommends protected species identification training,

recommends that vessel operators and crews maintain a

vigilant watch for marine mammals and slow down or

stop their vessel to avoid striking protected species, and

requires operators to report sightings of any injured or

dead protected species.

2012‐BSEE‐G01 Marine Trash and Debris Awareness

and Elimination

Instructs operators to exercise caution in the handling and

disposal of small items and packaging materials; requires

the posting of placards at prominent locations on offshore

vessels and structures; and mandates a yearly marine

trash and debris awareness training and certification

process.

2010‐N10

Statement of Compliance with

Applicable Regulations and

Evaluation of Information

Demonstrating Adequate Spill

Response and Well Containment

Resources

Informs operators using subsea blowout preventers

(BOPs) or surface BOPs on floating facilities that

applications for well permits must include a statement

signed by an authorized company official stating that the

operator will conduct all activities in compliance with all

applicable regulations, including the increased safety

measures regulations (75 FR 63346).    Informs operators

that BOEM will be evaluating whether each operator has

submitted adequate information demonstrating that it

has access to and can deploy containment resources to

promptly respond to a blowout or other loss of well

control.

2010‐N06

Information Requirements for

Exploration Plans, Development and

Production Plans, and Development

Operations Coordination

Documents on the OCS

Rescinds the limitations set forth in NTL 2008‐G04

regarding a blowout scenario and worst case discharge

scenario, and provides guidance regarding the

information required in blowout scenario and worst case

discharge scenario descriptions.

FOR PUBLIC RELEASE
Table 1.  (Continued).

Garden Banks Block 386 February 2012

Environmental Impact Analysis for Supplemental Exploration Plan Page 4

NTL Title Summary

2009‐G40 Deepwater Benthic Communities

Guidance for avoiding and protecting high‐density

deepwater benthic communities (including

chemosynthetic and deepwater coral communities) from

damage caused by OCS oil and gas activities in water

depths greater than 300 m (984 ft).  Prescribes separation

distances of 610 m (2,000 ft) from each mud and cuttings

discharge location and 76 m (250 ft) from all other

seafloor disturbances.

2009‐G39 Biologically Sensitive Underwater

Features and Areas

Guidance for avoiding and protecting biologically sensitive

features and areas (i.e., topographic features, pinnacles,

low relief live bottom areas, and other potentially

sensitive biological features) when conducting OCS

operations in water depths less than 300 m (984 ft) in the

Gulf of Mexico.

2009‐G06 Military Warning and Water Test

Areas

Provides contact links to individual command

headquarters for the military warning and water test

areas in the Gulf of Mexico.    Lease stipulations require

lessees or designated operators to enter into an

agreement with the appropriate individual military

command headquarters concerning the control of

electromagnetic emissions and use of boats and aircraft in

the applicable warning area or water test area before

commencing such traffic.

2008‐G04

Information Requirements for

Exploration Plans and Development

Operations Coordination

Documents

Guidance on the information requirements for OCS plans,

including EIA requirements and information regarding

compliance with the provisions of the Endangered Species

Act and Marine Mammal Protection Act.

2005‐G07 Archaeological Resource Surveys

and Reports

Provides guidance on regulations regarding archaeological

discoveries, specifies requirements for archaeological

resource surveys and reports, and outlines options for

protecting archaeological resources.

2011‐JOINT‐G01

Revisions to the List of OCS Blocks

Requiring Archeological Resources

Surveys and Reports

Provides new information of which OCS blocks require

archeological surveys and reports and required line

spacing in each block.    This NTL does not resend

NTL 2005‐G07.

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A.  Impact‐Producing Factors

Table 2 is a matrix of impact‐producing factors (IPFs) and potentially affected environmental

resources adapted from Form MMS‐142.    An “X” indicates that an IPF could reasonably be

expected to affect a certain resource, and a dash (‐‐) indicates no impact or negligible impact.  

Where there may be an effect, an analysis is provided in Section C.    Potential IPFs for the

proposed activity are listed below and briefly discussed in the following subsections:

 Drilling rig presence (including noise and lights);

 Physical disturbance to the seafloor;

 Air pollutant emissions;

 Effluent discharges;

 Water intake;

 Onshore waste disposal;  

 Marine debris;

 Support vessel and helicopter traffic; and

 Accidents.

A.1 Drilling Rig Presence (including noise and lights)

The drilling rig proposed for this SEP is a DP semisubmersible rig.  DP semisubmersibles use a

global positioning system (GPS) and sensors in conjunction with their own propellers and

thrusters to maintain position.    Essentially, through satellite navigation, the location of the

vessel is precisely monitored, and thrusters positioned at various locations about the vessel’s

hull are activated to provide any required station keeping adjustment.  This allows operations at

sea where mooring or anchoring is not feasible.

The drilling rig for the wells proposed in this SEP will be on site for an estimated 640 days.  The

physical presence of the drilling rig in the ocean can attract pelagic fishes and other marine life,

as discussed in Section C.5.1.

Drilling operations produce noise that includes strong tonal components at low frequencies, and

in some cases infrasonic frequencies (MMS, 2000).    Drilling noise from drillships and

semisubmersibles is not particularly intense and is strongest at low frequencies, averaging

10 to 500 Hz (Richardson et al., 1995).    Sound and vibrations from a drilling rig flow into the

water either through the air or through the risers (MMS, 2000).    Drilling rigs also maintain

exterior lighting for navigational and aviation safety in accordance with applicable Federal safety

regulations.

A.2 Physical Disturbance to the Seafloor

In water depths of 600 m (1,969 ft) or greater, DP semisubmersibles disturb only a very small

area of the seafloor around the wellbore (SHL) where the bottom template and blowout

preventer (BOP) are located.  Depending on the specific well configuration, this area is generally

about 0.25 ha (0.62 ac) (MMS, 2007b).

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Table 2. Matrix of impact‐producing factors and affected environmental resources. X = potential impact; dash (‐‐) = no im

Impact‐producing Factors

Environmental Resources Drilling Rig Presence (incl.

noise & lights)

PhysicalDisturbanceto Seafloor

AirPollutantEmissions

EffluentDischarges

WaterIntake

OnshoreWasteDisposal

MarineDebris

SuppoVesseTraffic

Physical/Chemical Environment

Air quality   ‐‐  ‐‐  X(9)  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  Water quality  ‐‐  ‐‐  ‐‐  X ‐‐  ‐‐  ‐‐  ‐‐  

Seafloor Habitats and Biota

Soft bottom benthic communities  ‐‐  X ‐‐  X ‐‐  ‐‐  ‐‐  ‐‐  High‐density deepwater benthic communities  ‐‐  X(4)  ‐‐  X(4)  ‐‐  ‐‐  ‐‐  ‐‐  Designated topographic features  ‐‐  ‐‐(1)  ‐‐  ‐‐(1)  ‐‐  ‐‐  ‐‐  ‐‐  Pinnacle trend area live bottoms  ‐‐  ‐‐(2)  ‐‐  ‐‐(2)  ‐‐  ‐‐  ‐‐  ‐‐  Eastern Gulf live bottoms  ‐‐  ‐‐(3)  ‐‐  ‐‐(3)  ‐‐  ‐‐  ‐‐  ‐‐  

Threatened, Endangered, and Protected Species and Critical Habitat

Sperm whale (endangered) X(8)  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  X(8) West Indian manatee (endangered)  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  X(8)  Endangered mysticete whales ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  Non‐endangeredmarinemammals(protected) X ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  X Sea turtles (endangered/threatened) X(8)  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  X(8) Piping Plover (threatened)  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  Whooping Crane (endangered) ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  Gulf sturgeon (threatened)  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  Smalltooth sawfish (endangered)  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  Beach mice (endangered) ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  Elkhorn coral (endangered) ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  

Coastal and Marine Birds

Marine birds X ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  X Shorebirds and coastal nesting birds  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  X 

Fisheries Resources

Pelagic communities and ichthyoplankton X ‐‐  ‐‐  X X ‐‐  ‐‐  ‐‐  Essential Fish Habitat X ‐‐  ‐‐  X X  ‐‐  ‐‐  ‐‐  

Archaeological Resources

Shipwreck sites ‐‐  ‐‐(7)  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  Prehistoric archaeological sites  ‐‐  ‐‐(7)  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  

Coastal Habitats and Protected Areas

Beaches ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  X Wetlands and seagrass beds  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  X Coastal wildlife refuges and wilderness areas  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  

Socioeconomic and Other Resources

Recreational and commercial fishing X ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  Public health and safety  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  Employment and infrastructure  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  Recreation and tourism  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  Land use  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  Other marine uses  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  

WCD = worst case discharge.

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Table 2 Footnotes and Applicability:

(1) Activities that may affect a marine sanctuary or topographic feature.  Specifically, if the well, rig site, or any

anchors will be on the seafloor within the following:

(a) 4‐mi zone of the Flower Garden Banks, or the 3‐mi zone of Stetson Bank;

(b) 1,000‐m, 1‐mi, or 3‐mi zone of any topographic feature (submarine bank) protected by the Topographic

Features Stipulation attached to an Outer Continental Shelf (OCS) lease;

(c) Essential Fish Habitat (EFH) criteria of 500 ft from any no‐activity zone; or

(d) Proximity of any submarine bank (500‐ft buffer zone) with relief greater than 2 m that is not protected by

the Topographic Features Stipulation attached to an OCS lease.

 Not applicable.    The lease is not within or near any marine sanctuary, topographic feature, or

no‐activity zone.  There are no submarine banks in the blocks.

(2) Activities with any bottom disturbance within an OCS lease block protected through the Live Bottom

(Pinnacle Trend) Stipulation attached to an OCS lease.

 The Live Bottom (Pinnacle Trend) Stipulation is not applicable to the lease area.

(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.  

 The Live Bottom (Low‐Relief) Stipulation is not applicable to the lease area.

(4) Activities on blocks designated by the BOEM as being in water depths 300 m or greater.

 No impacts on high‐density deepwater benthic communities are anticipated.  There are chemosynthetic

and deepwater coral communities in GB 386 but no features indicative of high‐density chemosynthetic

communities or coral communities are located within 610 m (2,000 ft) of any drilling mud/cuttings

discharge location.   

(5) Exploration or production activities where H2S concentrations greater than 500 ppm might be encountered.  

 Based on 30 CFR 250.490(c) and 550.215, Hess is requesting that BOEM classify the area as “H2S absent.”   

(6) All activities that could result in an accidental spill of produced liquid hydrocarbons or diesel fuel that 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.

 Accidental hydrocarbon spills could affect the resources marked (X) in the matrix, and impacts are

analyzed in Section C.

(7) All activities that involve seafloor disturbances, including anchor emplacements, in any OCS block designated

by the BOEM 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.

 No impacts on archaeological resources are expected.  The lease area is not on the list of high‐probability

blocks for shipwrecks and is well beyond the 60‐m depth contour used by the BOEM as the seaward

extent for prehistoric archaeological site potential in the Gulf of Mexico.

(8) All activities that you determine might have an adverse effect on endangered or threatened marine mammals

or sea turtles or their critical habitats.  

 IPFs that may affect marine mammals, sea turtles, or their critical habitats include drilling rig presence

and discharges, support vessel and helicopter traffic, and accidents.  See Section C.

(9) Production activities that involve transportation of produced fluids to shore using shuttle tankers or barges.

 Not applicable.

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A.3 Air Pollutant Emissions

Air pollutant emissions associated with the proposed activities are estimated to be insignificant

(see SEP Appendix H).  Offshore air pollutant emissions will result from operations of the drilling

rig, as well as service vessels and helicopters.  These emissions occur mainly from combustion of

diesel fuel.    The combustion of fuels occurs on diesel‐powered generators, pumps, or motors

and from lighter fuel motors.  Primary air pollutants typically associated with OCS activities are

suspended particulate matter (PM), sulfur oxides (SOx), nitrogen oxides (NOx), volatile organic

compounds (VOCs), and carbon monoxide (CO).

The Air Quality Emissions Report prepared in accordance with BOEM requirements

demonstrates that the projected emissions are below exemption levels set by the applicable

regulations in 30 CFR 550.303.  Based on this and the distance to shore, it can be concluded that

the emissions will not significantly affect the air quality of the onshore area for any of the

criteria pollutants.  No further analysis or control measures are required.

A.4 Effluent Discharges

Effluent discharges are summarized in SEP Appendix G.    All offshore discharges will be in

accordance with requirements of the National Pollutant Discharge Elimination System (NPDES)

General Permit No. GMG290000 issued by the U.S. Environmental Protection Agency (USEPA).  

Any discharges will be in compliance with the permit terms and monitored as required by the

permit.

Water‐based drilling muds and cuttings will be released at the seafloor during the initial well

intervals before the marine riser that allows their return to the surface is set.  Excess cement

slurry will also be released at the seafloor during casing installation for the riserless portion of

the drilling operations.    Synthetic‐based drilling muds (SBMs) will be collected on the rig and

transported to Port Fourchon for recycling at an approved facility.  Cuttings wetted with SBMs

will be discharged to the seafloor in accordance with the NPDES permit.

Other effluent discharges in accordance with the NPDES permit will include excess cement,

non‐contact cooling water, treated sanitary and domestic wastes, deck drainage, desalination

unit brine, uncontaminated fresh water and seawater, and ballast water.

A.5 Water Intake

Seawater will be drawn from the ocean for once‐through, non‐contact cooling of machinery on

the drilling rig.  Section 316(b) of the Clean Water Act requires NPDES permits to ensure that the

location, design, construction, and capacity of cooling water intake structures reflect the best

technology available to minimize adverse environmental impact from impingement and

entrainment of aquatic organisms.  Construction of the rig being considered for use for activities

described in this SEP will be completed in 2012 and is considered a “new” facility as defined by

the NPDES General Permit No. GMG290000.  The rig will comply with the cooling water intake

regulations prescribed in the permit.

A.6 Onshore Waste Disposal

Wastes generated during drilling are tabulated in SEP Appendix G.  Approximately 168,000 lbs

(76,205 kg) of trash will be generated during the drilling of the wells proposed under this SEP.  

This trash will be transported in storage bins on the work boat to shore, where it will be recycled

in accordance with applicable regulations.

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A.7 Marine Debris

Hess will comply with all regulations relating to solid waste handling and disposal, including the

International Convention for the Prevention of Pollution from Ships (MARPOL 73/78) Annex V

requirements and USEPA and U.S. Coast Guard (USCG) regulations, as well as those of BOEM.  

For example, BOEM regulations at 30 CFR 250.300(a) and (b)(6) prohibit operators from

deliberately discharging containers and other similar materials (i.e., trash and debris) into the

marine environment, and 30 CFR 250.300(c) requires durable identification markings on

equipment, tools and containers (especially drums), and other material.    USEPA and

USCG regulations require operators to become proactive in avoiding accidental loss of solid

waste items by developing waste management plans, posting informational placards,

manifesting trash sent to shore, and using special precautions such as covering outside trash

bins to prevent accidental loss of solid waste.    In addition to the regulations in 30 CFR 250,

BSEE issued NTL 2012‐BSEE‐G01, which instructs operators to exercise caution in the handling

and disposal of small items and packaging materials, requires the posting of placards at

prominent locations on offshore vessels and structures, and mandates a yearly marine trash and

debris awareness training and certification process.

A.8 Support Vessel and Helicopter Traffic

Hess will use existing shorebase facilities at Port Fourchon, Louisiana, for onshore support for

vessel activities.  Air transportation (helicopters) will be based at facilities in Galliano, Louisiana.  

No terminal expansion or construction is planned at either location.

The project will be supported by one crew boat, one service boat, and two supply boats.  The

crew vessels will make approximately one round‐trip per week, supply boats will make

approximately three round‐trips per week, and service boats will make daily round‐trips.  The

boats typically will move to the project area via the most direct route from the shorebase.

A helicopter will make approximately eight round‐trips per week between the drilling rig and the

heliport.  The helicopter will be used to transport personnel and small supplies and will normally

take the most direct route of travel between the shorebase and the lease area when air traffic

and weather conditions permit.    Helicopters typically maintain a minimum altitude of 213 m

(700 ft) while in transit offshore, 305 m (1,000 ft) over unpopulated areas or across coastlines,

and 610 m (2,000 ft) over populated areas and sensitive habitats such as wildlife refuges and

park properties.

A.9 Accidents

A.9.1 Types of Accidents Evaluated

The analysis in this EIA focuses on two potential accidents:

 a small fuel spill, which is the most likely type of spill during OCS development activities; and

 the WCD for this SEP, which is an oil spill resulting from an uncontrolled blowout.

The following subsections summarize assumptions about the sizes and fates of these spills, as

well as Hess’s spill response plans.  Impacts are analyzed in Section C.

The lease sale EIS (MMS, 2007b) analyzes three other types of accidents: chemical spills, vessel

collisions, and loss of well control.  The information in the lease sale EIS is incorporated here.  

These accidents are discussed briefly in Section A.9.4.

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A.9.2 Small Fuel Spill

Spill Size.  According to analyses in MMS (2007b) and BOEM (2011, 2012), the most likely type of

small spill (<1,000 bbl) as a result of OCS activities is a minor diesel fuel spill.  Historically, most

diesel spills have been <1 bbl, and this size is predicted to be the most common in ongoing and

future OCS activities in the Western and Central Gulf of Mexico Planning Areas.    As spill size

increases, the incident rate declines dramatically (MMS, 2007b; BOEM, 2011, 2012).    The

average size for spills <1 bbl is 0.07 bbl, and the median size for spills of 1 to 10 bbl is 3 bbl

(MMS, 2007b).    For this analysis, a small diesel fuel spill of 3 bbl is assumed.    Operational

experience suggests that the most likely cause of such a spill would be a hose rupture resulting

in the loss of the contents of a fuel transfer hose, which is less than 3 bbl.

Spill Fate.  The fate of a small fuel spill in the lease area would depend on meteorological and

oceanographic conditions at the time, as well as the effectiveness of spill response activities.  

However, given the open ocean location of the lease area and response actions, it is expected

that impacts from a small spill would be minimal (BOEM, 2011, 2012).

The water‐soluble fractions of diesel are dominated by two‐  and three‐ringed polycyclic

aromatic hydrocarbons (PAHs), which are moderately volatile (National Research Council [NRC],

2003).  The constituents of these oils are light to intermediate in molecular weight and can be

readily degraded by aerobic microbial oxidation.   Diesel is so light that it will not sink to the

seafloor.   Diesel dispersed in the water column can adhere to suspended sediments, but this

generally occurs only in coastal areas with high suspended solids loads (NRC, 2003) and would

not be expected to occur to any appreciable degree in offshore waters of the Gulf of Mexico.  

Diesel oil is readily and completely degraded by naturally occurring microbes (National Oceanic

and Atmospheric Administration [NOAA], 2006).

For purposes of this EIA, the fate of a small diesel fuel spill was estimated using NOAA’s

Automated Data Inquiry for Oil Spills 2 (ADIOS2) model.  This model uses the physical properties

of oils in its database to predict the rate of evaporation and dispersion over time, as well as

changes in the density, viscosity, and water content of the product spilled.  It is estimated that

over 90% of a small diesel spill would be evaporated or dispersed within 24 hours.  The area of

the sea surface with diesel fuel on it during this 24‐hour period would range from 0.5 to 5 ha

(1.2 to 12 ac) depending on sea state and weather conditions.

The ADIOS2 results, coupled with spill trajectory information discussed below for a large spill,

indicate that a small fuel spill would not have any impacts on coastal or shoreline resources.  

The lease area is 130 miles (209 km) south‐southwest of the nearest shoreline (Louisiana).  

Modeling results discussed below indicate that a spill in the lease area would have a 4% or less

probability of reaching any coastline within 10 days after a spill.    By that time, essentially

100% of a small fuel spill would have been dispersed or evaporated by natural processes,

without taking into account Hess’s response measures.  MMS (2007b) similarly concluded that

spills <1,000 bbl are not expected to persist as a slick on the surface of the water beyond a few

days and are unlikely to make landfall or reach coastal waters prior to breaking up.  

MMS (2007b) noted that this conclusion is supported by a previous analysis of 3‐day trajectory

model runs, previous weathering analyses, and historical records of spill incidents.

Spill Response.    In the unlikely event the shipboard procedures fail to prevent a fuel spill,

response equipment and trained personnel would be activated so that any spill effects would be

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localized and would result only in short‐term environmental consequences.    SEP Appendix I

provides a detailed discussion of Hess’s response to a spill.

A.9.3 Crude Oil Spill (Worst Case Discharge)

Spill Size.  In accordance with requirements of NTL 2010‐N06, Hess has estimated a WCD for this

SEP as 228,936 bbls for the initial 24 hours and a 30‐day average rate of 127,984 bbl of oil per

day (SEP Appendix I).

Historically, blowouts are rare events and most do not result in oil spills.    Holand (1997)

estimated a probability of 0.0021 for a blowout during exploration drilling in deep water based

on U.S. Gulf of Mexico data.    An updated analysis using the SINTEF database estimates a

blowout frequency of 0.0017 per exploratory well for non‐North Sea locations (International

Association of Oil & Gas Producers, 2010).  As noted by MMS (2007b), from 1992 to 2005, half of

blowouts lasted less than half a day, and fewer than 10% of blowouts resulted in spilled oil.  

BOEM is in the process of updating these spill frequency estimates to include the recent

Macondo event; however, significant changes to the spill rates for the entire OCS are not

anticipated (BOEM, 2011, 2012).    As noted in the Introduction, the baseline risk of a

catastrophic blowout is estimated to be once every 26 years (BOEMRE Interim Final Drilling

Safety Rule, 75 FR 63365 – 10 October 2010).

Included in SEP Appendix I are Hess’s calculations and information as required by

NTL 2010‐N06, including descriptions of measures to prevent a blowout, reduce the likelihood of

a blowout, and conduct effective and early intervention in the event of a blowout.  Hess will also

comply with NTL 2010‐N10 and the Interim Final Drilling Safety Rule, which specifies additional

safety measures for OCS activities.

Spill Trajectory.  The fate of a large oil spill in the lease area would depend on meteorological

and oceanographic conditions at the time.    The Oil Spill Risk Analysis (OSRA) model is a

computer simulation of oil spill transport that uses realistic data for winds and currents to

predict spill fate.  Although this model has received some criticism recently (Earthjustice, 2011),

it is still the most widely scientifically accepted model for estimating the fate of small fuel spills.

The primary criticism of the OSRA model results as provided in Ji et al. (2004) was that the

model did not evaluate the fate of a spill over time periods longer than 30 days, nor did it

predict the fate of a release that continues over a period of weeks or months, as occurred in the

Macondo (Deepwater Horizon) incident.  Also as noted by Ji et al. (2004), the OSRA model does

not take into account the chemical composition or biological weathering of oil spills, the

spreading and splitting of oil spills, or spill response activities.  The model does not assume a

particular spill size but has generally been used by the BOEM to evaluate contact probabilities

for spills greater than 1,000 bbl.

To address this criticism, a special OSRA run was conducted for the recent BOEM Central and

Western Gulf of Mexico Planning Area Supplemental EISs (BOEM, 2011, 2012) in order to

estimate the impacts of a possible future catastrophic long‐duration oil spill.  In this OSRA model

run, a hypothetical high‐volume, long‐duration oil spill was assumed to have occurred, and the

analysis emphasized modeling a spill that continued for 90 consecutive days, with each

trajectory tracked for up to 120 days.

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The OSRA model run for this analysis was conducted for five hypothetical launch points in the

BOEM Central and Western Gulf of Mexico Planning Areas.    These launch points were

deliberately located in areas identified as having a high possibility of containing large oil

reserves.  

The five launch point areas were as follows:

1. Central Gulf of Mexico shelf area west of the Mississippi River—28.98660° N latitude,

92.17851° W longitude;

2. Central Gulf of Mexico shelf area east of the Mississippi River—29.91388° N latitude,

88.15338° W longitude;

3. Central Gulf of Mexico slope area—27.31998° N latitude, 90.22203° W longitude;

4. Western Gulf of Mexico shelf area—27.55423° N latitude, 96.76627° W longitude; and

5. Western Gulf of Mexico slope area—27.51367° N latitude, 94.51836° W longitude.

The results for Launch Point 3, the launch point nearest to the project area, are presented in

Table 3.   

Table 3. Conditional probabilities expressed as percentage chance that an oil spill starting at

Launch Point 3 will contact a certain parish, county, or coastline within 120 days

(Adapted from: BOEM, 2011, 2012, Appendix C).

Season Winter Spring Summer Fall

Day 3 10 30 120 3 10 30 120 3 10 30 120 3 10 30 120

County or Parish Percent Chance

Cameron, Texas  ‐‐  ‐‐  ‐‐  2  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  2  ‐‐  ‐‐  ‐‐  2

Willacy, Texas  ‐‐  ‐‐  ‐‐  3  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  2  ‐‐  ‐‐  ‐‐  3

Kenedy, Texas  ‐‐  ‐‐  ‐‐  8  ‐‐  ‐‐  ‐‐  1  ‐‐  ‐‐  ‐‐  9  ‐‐  ‐‐  ‐‐  5

Kleberg, Texas  ‐‐  ‐‐  1 6  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  4  ‐‐  ‐‐  1 6

Nueces, Texas  ‐‐  ‐‐  1 6  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  2  ‐‐  ‐‐  1 2

Aransas, Texas  ‐‐  ‐‐  ‐‐  5  ‐‐  ‐‐  ‐‐  1  ‐‐  ‐‐  ‐‐  3  ‐‐  ‐‐  ‐‐  2

Calhoun, Texas  ‐‐  ‐‐  1 6  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  6  ‐‐  ‐‐  1 4

Matagorda, Texas  ‐‐  ‐‐  2 17  ‐‐  ‐‐  3 4  ‐‐  ‐‐  ‐‐  11  ‐‐  ‐‐  1 6

Brazoria, Texas  ‐‐  ‐‐  3 12  ‐‐  ‐‐  1 3  ‐‐  ‐‐  2 8  ‐‐  ‐‐  1 5

Galveston, Texas  ‐‐  ‐‐  3 10  ‐‐  ‐‐  3 6  ‐‐  ‐‐  2 5  ‐‐  ‐‐  ‐‐  4

Jefferson, Texas  ‐‐  ‐‐  1 4  ‐‐  ‐‐  7 9  ‐‐  ‐‐  1 1  ‐‐  ‐‐  ‐‐  2

Cameron, Louisiana  ‐‐  ‐‐  1 4  ‐‐  ‐‐  11 12  ‐‐  1 1 4  ‐‐  ‐‐  ‐‐  4

Vermilion, Louisiana  ‐‐  ‐‐  1 2  ‐‐  ‐‐  5 6  ‐‐  1 1 2  ‐‐  ‐‐  ‐‐  ‐‐ 

Iberia, Louisiana  ‐‐  ‐‐  ‐‐  1  ‐‐  ‐‐  4 4  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐ 

Terrebonne, Louisiana  ‐‐  1 2 3  ‐‐  4 12 14  ‐‐  ‐‐  ‐‐  2  ‐‐  ‐‐  ‐‐  ‐‐ 

Lafourche, Louisiana  ‐‐  ‐‐  1 1  ‐‐  2 8 10  ‐‐  ‐‐  1 2  ‐‐  ‐‐  ‐‐  ‐‐ 

Jefferson, Louisiana  ‐‐  ‐‐  ‐‐  1  ‐‐  ‐‐  2 2  ‐‐  ‐‐  1 1  ‐‐  ‐‐  ‐‐  ‐‐ 

Plaquemines, Louisiana  ‐‐  ‐‐  ‐‐  1  ‐‐  2 10 12  ‐‐  ‐‐  1 2  ‐‐  ‐‐  ‐‐  ‐‐ 

Jackson, Mississippi  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  1 1  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐ 

Baldwin, Alabama  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  1 1  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐ 

Bay, Florida ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  1  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐ 

Franklin, Florida  ‐‐  ‐‐  ‐‐  1  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐ 

Monroe, Florida  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  1  ‐‐  ‐‐  ‐‐  1

Dade, Florida  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  ‐‐  1  ‐‐  ‐‐  ‐‐  ‐‐ 

“‐‐” = Values <0.5%; any areas where percent chance within 120 days of all seasons are all <0.5% are not shown.OSRA is a

preliminary risk assessment model.  In the event of an actual oil spill, real time monitoring and trajectory modeling would be

conducted using current and wind data available from the rigs and permanent production structures in the area.  Satellite and

aerial monitoring of the plume and real time trajectory modeling using wind and current data would continue on a daily basis to

help position equipment and human resources throughout the duration of any major spill or uncontrolled release.

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Weathering.    Following an oil spill, several physical, chemical, and biological processes,

collectively called weathering, interact to change the physical and chemical properties of the oil,

influencing potential effects to marine organisms and ecosystems.    The most important

weathering processes include spreading, evaporation, dissolution, dispersion into the water

column, formation of water‐in‐oil emulsions, photochemical oxidation, microbial degradation,

adsorption to suspended particulate matter, and stranding on shore or sedimentation to the

seafloor (NRC, 2003).

Weathering decreases the concentration of oil and produces changes in its chemical

composition, physical properties, and toxicity.    The more toxic, light aromatic and aliphatic

hydrocarbons are lost rapidly by evaporation and dissolution from a slick on the water surface.  

Evaporated hydrocarbons are degraded rapidly by sunlight.  Biodegradation of oil on the water

surface and in the water column by marine bacteria removes first the n‐alkanes and then the

light aromatics from the oil.    Other petroleum components are biodegraded more slowly.  

Photo‐oxidation attacks mainly the medium and high molecular weight PAHs in the oil on the

water surface.

Spill Response.    The BOEM has issued recent NTLs and guidance documents that clarify

additional oil‐spill requirements after the Macondo spill occurred (BOEM, 2011, 2012).  These

spill‐response‐related NTLs are listed in Table 1, and the guidance documents are as follows:  

NTL 2010‐N10—Statement of Compliance with Applicable Regulations and Evaluation of

Information Demonstrating Adequate Spill Response and Well Containment Resources:

This NTL, effective 8 November 2010, applies only to operators conducting operations

using subsea or surface BOPs on floating facilities.  It states that lessees and operators must

submit a statement signed by an authorized company official with each application for a

well permit indicating that they will conduct all of their authorized activities in compliance

with all applicable regulations, including the Increased Safety Measures Regulations at

75 FR 63346.  The NTL also informs lessees that BOEM will evaluate the operator’s current

OSRP to determine whether or not the operator has submitted adequate information to

demonstrate that they have access to and can deploy surface and subsea containment

resources that would be adequate to promptly respond to a blowout or other loss of well

control; therefore, there is an incentive for voluntary compliance.

NTL 2010‐N06—Information Requirements for Exploration Plans, Development and

Production Plans, and Development Operations Coordination Documents on the OCS:

This NTL, effective 18 June 2010, explains the procedures for the lessee or operator to

submit supplemental information for new or previously submitted Exploration plans (EPs),

Development and Production Plan (DPPs), or Development Operations Coordination

Documents (DOCDs).    The required supplemental information includes the following:

(1) a description of the blowout scenario as required by 30 CFR 550.213(g) and 550.243(h);

(2) a description of the assumptions and calculations used in determining the volume of the

WCD required by 30 CFR 550.219(a)(2)(iv) (for EPs) or 30 CFR 550.250(a)(2)(iv) (for DPPs

and DOCDs); and (3) a description of the measures proposed that would enhance the

ability to prevent a blowout, reduce the likelihood of a blowout, and conduct effective and

early intervention in the event of a blowout, including arrangements for drilling relief wells

and any other measures proposed.    The early intervention methods of the third

requirement could include the surface and subsea containment resources that BOEM

announced in NTL‐2010‐N10, which states that BOEM will review the operator’s current

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OSRP to ensure that the measures are adequate to promptly respond to a blowout or other

loss of well control.

Hess’s Gulf of Mexico Regional OSRP was approved by BOEMRE in March 2010, modified in

October 2010, and certified in January 2011.    The OSRP provides a detailed plan for Hess to

respond to and rapidly and effectively manage oil spills that may result from drilling and

production operations.

In the event of a WCD, Hess has access to surface and subsea response/containment capabilities

that could be implemented through various organizations under contract.  Hess's primary spill

response equipment providers are Clean Gulf Associates (CGA) and National Response

Corporation.    CGA is supported by the Marine Spill Response Corporation (MSRC), which is

responsible for storing, inspecting, maintaining, and dispatching CGA’s equipment.  The National

Response Corporation network is comprised of the Independent Contractors Network (ICN) and

the Marine Resource Network (MRN) (see SEP Appendix I).   

CGA and National Response Corporation maintain a dedicated fleet of vessels and other spill

response equipment located at designated ports, and have the ability to plan the mobilization

and rapid deployment of spill response resources on a 24‐hour, 7 days a week basis.    CGA’s

equipment is strategically positioned across the Gulf of Mexico from Brownsville, Texas to Key

West, Florida; this equipment is operated by Trained Oil Spill Removal Organizations (OSROs).  

The resources available from CGA and National Response Corporation will be deployed and

operated by Hazardous Waste Operations and Emergency Response (HAZWOPER) trained

personnel with proven operations experience and local knowledge.    See SEP Appendix I for a

detailed description of Hess’s site‐specific response to the WCD for this plan.

A.9.4 Other Accidents Not Analyzed in Detail

The lease sale EIS (MMS, 2007b) discusses three other types of accidents: chemical spills, vessel

collisions, and loss of well control.  The information from the EIS on these topics remains valid

and is incorporated by reference into this document.    These accidents are discussed briefly

below along with a hydrogen sulfide (H2S) release.  There are no other site‐specific issues for the

drilling of the wells proposed in this SEP.

Chemical Spills.  Chemicals are stored and used to condition drill muds during production and in

well completions, stimulation, and workover procedures.   The relative quantity of their use is

reflected in the largest volumes spilled.  Completion fluids compose the largest quantity of fluids

used and thus are the largest releases.  Between 5 and 15 chemical spills are anticipated each

year, with the majority being <50 bbl in size.  The most common chemicals spilled are methanol,

ethylene glycol, and zinc bromide.  Additional production chemicals are needed in deepwater

operations where gas hydrates tend to form.  Spill volumes are anticipated to remain about the

same, but spill frequency can be expected to improve because of advances in subsea processing

(BOEM, 2011, 2012).

Synthetic‐based Fluid Spills.  In deepwater drilling, SBMs are preferred over petroleum oil‐based

muds (OBMs) due to their superior environmental properties.    Synthetic‐based fluids (SBFs)

used in SBMs are less toxic to the marine environment and have the potential to biodegrade.  

SBMs have been used since the mid 1990s.    Three SBF spills >1,000 bbl occurred between

2001 and 2004.  Between 5 and 20 SBF releases are anticipated each year as a result of offshore

drilling programs; the majority of these releases are <50 bbl in size.  The volume of the synthetic

portion of the drill fluid rather than the total volume of the drill fluid is now used to describe

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spill size.  Accidental riser disconnects could result in the release of large quantities of drilling

fluids and are of particular concern when SBMs are in use (BOEM, 2011, 2012).

Vessel Collisions.    BOEMRE data show that from 1996 to 2009 there were 226 OCS‐related

collisions.   Most collision mishaps are the result of service vessels colliding with platforms or

vessel collisions with pipeline risers.  Approximately 10% of vessel collisions with platforms in

the OCS resulted in diesel spills, and in several collision incidents, fires resulted from

hydrocarbon releases.    To date, the largest diesel spill associated with a collision occurred in

1979 when an anchor‐handling boat collided with a drilling platform in the Main Pass (MP)

leasing area, spilling 1,500 bbl of diesel.  Diesel fuel is the product most frequently spilled, but

oil, natural gas, corrosion inhibitor, hydraulic fluid, and lube oil have also been released as the

result of vessel collisions.  Human error accounted for approximately half of all reported vessel

collisions from 2006 to 2009.  As summarized by MMS (2007b) and BOEM (2011, 2012), vessel

collisions occasionally occur during routine operations.    Some of these collisions have caused

spills of diesel fuel or chemicals.  Hess will comply with all USCG and BOEM‐mandated safety

requirements to minimize the potential for vessel collisions.

Loss of Well Control.  A loss of well control is the uncontrolled flow of a reservoir fluid that may

result in the release of gas, condensate, oil, drilling fluids, sand, or water.  Loss of well control is

a broad term that includes very minor up to the most serious well control incidents, while

blowouts are considered to be a subset of more serious incidents with greater risk of oil spill or

human injury (MMS, 2007b).  Loss of well control may result in the release of synthetic drilling

fluid or loss of oil.  Hess has a robust system in place to prevent loss of well control.  Measures

to prevent a blowout, reduce the likelihood of a blowout, and conduct effective and early

intervention in the event of a blowout are described in SEP Appendix I as required by

NTL 2010‐06.  The potential for a loss‐of‐well‐control event will be minimized by adhering to the

requirements of applicable regulations such as the Interim Final Drilling Safety Rule and

NTL 2010‐N10, which specify additional safety measures for OCS activities.  

H2S Release.    Pursuant to 30 CFR 250.490(c), Hess is requesting in the SEP that the BOEM

Regional Supervisor, Field Operations, classify the area in the proposed drilling operations as

"H2S absent."

B.  Affected Environment

The lease area is in the central Gulf of Mexico, 130 miles (209 km) south‐southwest of the

nearest shoreline (Louisiana) and 159 miles (256 km) from the onshore support base at

Port Fourchon, Louisiana (Figure 1).    Water depth at the wellsites is approximately 2,623 ft

(800 m) (Figure 2).

Chemosynthetic and deepwater coral communities occur in GB 386.  However, no high‐density

chemosynthetic communities occur within a 610‐m (2,000‐ft) radius of the proposed surface

locations.   Detailed descriptions of the regional affected environment including meteorology,

oceanography, geology, air and water quality, benthic communities, threatened and

endangered species, biologically sensitive resources, archaeological resources, socioeconomic

conditions, and other marine uses is provided in recent lease sale EISs (MMS, 2007b, 2008).  

These regional descriptions remain valid and are incorporated by reference.    General

background information is presented below, and brief descriptions of each potentially affected

resource, including site‐specific and/or new information if available, are presented in Section C.

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Environmental Impact Analysis for Supplemental Exploration Plan 

Figure 2. Bathymetric map of the lease area showing surface hole locations of proposed Wells LL4, LL5, and LL6.

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The Macondo spill resulted in impacts to water quality in the area of the spill.  In addition to the

oil slick on the sea surface, plumes of submerged oil droplets were produced when subsea

dispersants were applied at the wellhead (Camilli et al., 2010; Hazen et al., 2010; Joint Analysis

Group, 2010a,b,c).  Despite limited information on the water quality of deep water, it is clear

that the conditions in the offshore waters of the Gulf of Mexico were altered by the Macondo

event.    Various monitoring efforts and environmental studies are in progress, but it is not

currently possible to precisely estimate the long‐term impacts the spill will have on offshore

water quality (BOEM, 2011, 2012).

The lease area is located approximately 249 miles (400 km) southwest of the Macondo spill site.  

Based on an analysis of satellite imagery (ESRI, 2010), the surface slick did not extend over the

lease area.  With the current information available, there is no evidence to suggest that water

quality in the lease area was affected by the Macondo incident.  Prior to the Macondo incident,

water quality in deep, offshore waters of the Gulf of Mexico was expected to be good, with low

levels of contaminants (Kennicutt, 2000).  Based on the information currently available, there is

no reason to expect any long‐term change in water quality conditions in the lease area from

those predicted in the recent lease sale EISs (MMS 2007b, 2008; BOEM, 2011, 2012).

C.  Impact Analysis

This section analyzes the potential direct and indirect impacts of routine activities and accidents.  

Impacts have been analyzed extensively in recent lease sale EISs for the Western and Central

Gulf of Mexico Planning Areas (MMS, 2007b, 2008) as well as the environmental assessment for

Gulf of Mexico deepwater operations and activities (MMS, 2000).    The information in these

documents is incorporated by reference.    Potential site‐specific issues are addressed in this

section.

C.1 Physical/Chemical Environment

C.1.1 Air Quality

There are no site‐specific air quality data for the project area due to the distance from shore.  

Because of the distance from shore‐based pollution sources and the lack of sources offshore, air

quality at the wellsites is expected to be good.  The attainment status of Federal OCS waters is

unclassified because there is no provision in the Clean Air Act for classification of areas outside

state waters (MMS, 2007b).

Louisiana, Mississippi, Alabama, and Florida coastal counties and parishes are in attainment of

the National Ambient Air Quality Standards (NAAQS) for all criteria pollutants (USEPA, 2011).  

Two metropolitan areas in Texas are nonattainment areas for 8‐hour ozone (Dallas‐Fort Worth

and Houston‐Brazoria), and El Paso County is a nonattainment area for PM10 (USEPA, 2011).

Winds in the region are driven by the clockwise circulation around the Bermuda High

(MMS, 2007b).    The Gulf of Mexico is located to the southwest of this center of circulation,

resulting in a prevailing southeasterly to southerly flow, which is conducive to transporting

emissions toward shore.  However, circulation is also affected by tropical cyclones (hurricanes)

during summer and fall and by extratropical cyclones (cold fronts) during winter.

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As noted earlier, based on calculations made pursuant to applicable regulations, emissions from

routine drilling activities are not expected to be significant as they are below exemption levels.  

Therefore, the only unanticipated effect on air quality would be from a small fuel spill and a

large oil spill (WCD).

BOEM reexamined the analysis for air quality presented in MMS (2007b, 2008) based on

additional information and in consideration of the Macondo oil spill event.  No substantial new

information was found that would alter the potential impacts on air quality presented in recent

lease sale EISs (BOEM, 2011, 2012).

Impacts of Air Pollutant Emissions

Air pollutant emissions are the only routine IPF likely to affect air quality.  Offshore air pollutant

emissions will result from the drilling rig operations, helicopters, and service vessels.    These

emissions occur mainly from combustion or burning of diesel fuel.    The combustion of fuels

occurs primarily on diesel‐powered generators, pumps, or motors and from lighter fuel motors.  

Primary air pollutants typically associated with OCS activities are suspended PM, SOx, NOx, VOCs,

and CO.  Emissions of pollutants into the atmosphere from these activities are not projected to

have significant effects on onshore air quality because of the prevailing atmospheric conditions,

emission rates and heights, and resulting pollutant concentrations.  As described in the BOEM

lease sale EISs, the incremental contribution to cumulative impacts resulting from activities

similar to Hess’s proposed activities is not significant and will not cause or contribute to a

violation of any NAAQS (MMS, 2007b, 2008).  Since the BOEM completed the lease sale EISs, the

USEPA adopted a new short‐term NAAQS for nitrogen dioxide (NO2).  The standard has not yet

been implemented in the Gulf Coast states, but given the levels of expected emissions and the

distance of the project from shore, emissions from the activities described in Hess’s proposed

SEP are not likely to contribute to violations of any NAAQS onshore.

Carbon dioxide (CO2) and methane (CH4) emissions from the project will constitute a small

incremental contribution to greenhouse gas emissions from all OCS activities.  According to the

Programmatic EIS (MMS, 2007a), estimated CO2 emissions from all OCS activities in the

2007‐2012 leasing program are about 0.08% to 0.016% of the global CO2 emissions from fossil

fuel combustion.  Greenhouse gas emissions may contribute to climate change, with important

effects on temperature, rainfall, frequency of severe weather, ocean acidification, and sea level

rise (Intergovernmental Panel on Climate Change, 2007).  Greenhouse gas emissions from this

proposed project represent a negligible contribution to the total greenhouse gas emissions from

reasonably foreseeable activities in the Gulf of Mexico area and would not significantly alter any

of the climate change impacts evaluated in the lease sale EIS (MMS, 2007b) or Programmatic EIS

(MMS, 2007a).

Due to the distance from shore, routine operations in the project area are not expected to have

any impact on air quality conditions along the coast, including nonattainment areas.  As noted in

the lease sale EIS (MMS, 2007b), emissions of air pollutants from routine activities in the Central

Gulf of Mexico Planning Area are projected to have minimal impacts to onshore air quality

because of the prevailing atmospheric conditions, emission heights, emission rates, and the

distance of these emissions from the coastline.    The Air Quality Emissions Report

(see SEP Appendix H) prepared in accordance with BOEM requirements shows that the

projected emissions are below exemption levels (Table 4); therefore, according to

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30 CFR 550.303, the emissions will not significantly affect the air quality of the onshore area for

any of the criteria pollutants.  No further analysis or control measures are required.

Table 4. Estimated air pollutant emissions in Garden Banks Block 386 over the life of the

project.

Estimated Tons   Year

PM SOx NOx VOC CO

2012 15.45 70.68 529.82 15.94 115.60

2013 52.99 242.28 1,816.26 54.67 396.27

2014 35.78 163.73 1,227.25 36.91 267.76

Exemption Calculation 4,329.00 4,329.00 4,329.00 4,329.00 87,251.82

CO = carbon monoxide; NOx = nitrogen oxides; PM = particulate matter; SOx = sulfur oxides; VOC = volatile organic

compound.

The Breton Wilderness Area, which is part of the Breton National Wildlife Refuge (NWR), is

designated under the Clean Air Act as a Prevention of Significant Deterioration (PSD) Class I air

quality area.    The BOEM is required to coordinate with the National Park Service (NPS) and

U.S. Fish and Wildlife Service (USFWS) if emissions from proposed projects may affect the

Breton Class I area.    Additional review and mitigation measures may be required for sources

within 186 miles (300 km) of the Breton Class I area that exceed emission limits agreed upon by

the administering agencies (NPS, 2010).    The lease area is approximately 225 miles (362 km)

from the Breton Wilderness Area, and air quality impacts on the Wilderness Area are not

expected.  

Impacts of a Small Fuel Spill

Potential impacts of a small spill on air quality are expected to be consistent with those analyzed

and discussed in EISs prepared for recent lease sales (MMS, 2007b, 2008; BOEM, 2011, 2012).  

The probability of a small spill would be minimized by Hess’s preventative measures during

routine operations, including fuel transfer.   In the unlikely event of a spill, implementation of

Hess’s OSRP will reduce the potential impacts.  SEP Appendix I includes a detailed discussion of

the spill response measures that would be employed.   Given the open ocean location of the

lease area, the extent and duration of air quality impacts from a small spill would not be

significant.

A small fuel spill would affect air quality near the spill site by introducing VOCs through

evaporation.  The ADIOS2 model (see Section A.9.2) indicates that over 90% of a small diesel

spill would be evaporated or dispersed within 24 hours.  The area of the sea surface with diesel

fuel on it would range from 0.5 to 5 ha (1.2 to 12 ac), depending on sea state and weather

conditions.

A small fuel spill would not affect coastal air quality because the spill would not be expected to

make landfall or reach coastal waters prior to breaking up (see Section A.9.2).

Impacts of a Large Oil Spill (WCD)

Potential impacts of a large oil spill on air quality are expected to be consistent with those

analyzed and discussed in recent lease sale EISs (MMS, 2007b, 2008; BOEM, 2011, 2012).

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A large oil spill (WCD) could potentially affect air quality by introducing VOCs through

evaporation from the slick.    The extent and persistence of impacts would depend on the

meteorological and oceanographic conditions at the time and the effectiveness of spill response

measures.    Real‐time wind and current data from the project area would be available at the

time of a spill and would be used to assess the fate and effects of VOCs released.  Additional air

quality impacts could occur if response measures included in situ burning of the floating oil.  

Burning would generate a plume of black smoke and result in emissions of NOx, SOx, CO, and

PM, as well as greenhouse gases.  However, in situ burning would occur only after authorization

from the USEPA.

Due to the lease area location (130 miles [209 km]) from the nearest shoreline, most air quality

impacts would occur in offshore waters with minimal chance to affect onshore air quality.

C.1.2 Water Quality

There are no site‐specific water quality data for the lease area.   Due to the lease location in

deep, offshore waters, water quality is expected to be good, with low levels of contaminants.  As

noted in a recent lease sale EIS (MMS, 2007b), deepwater areas in the northern Gulf of Mexico

are relatively homogeneous with respect to temperature, salinity, and oxygen.  Kennicutt (2000)

noted that the deepwater region has little evidence of contaminants in the dissolved or

particulate phases of the water column.   However, there are localized occurrences of natural

seepage of oil, gas, and brines in near‐surface sediments and up through the water column.

The lease area is located approximately 249 miles (400 km) from the Macondo spill site.  Based

on the general circulation pattern seen in the Gulf of Mexico and on satellite imagery

(ESRI, 2010), the surface slick from that discharge did not extend over the lease area during the

spill.  The existing water quality in the lease area is not expected to have been affected by the

Macondo release.

IPFs potentially affecting water quality are effluent discharges and two types of accidents:

a small fuel spill and a large oil spill (WCD).

Impacts of Effluent Discharges

In general, turbid water can be expected to extend between a few hundred meters and several

kilometers down current from the discharge point for water‐based drilling mud and cuttings.  

SBMs will be collected on the rig and transported to Port Fourchon for recycling and/or disposal

at an approved facility.    Cuttings wetted with SBMs will be discharged to the seafloor in

accordance with the NPDES permit.  There will be no persistent impacts on water quality in the

lease area (NRC, 1983; Neff, 1987; Neff et al., 2000).

Treated sanitary and domestic wastes, including those from support vessels, may have a slight

transient effect on water quality in the immediate vicinity of these discharges.  All NPDES permit

limitations and requirements and USCG regulations (as applicable) will be met, therefore, little

or no impact on water quality is anticipated.

Deck drainage includes all effluents resulting from rain, deck washings, and runoff from curbs,

gutters, and drains, including drip pans in work areas.  Rainwater that falls on uncontaminated

areas of the drilling rig will flow overboard without treatment.  However, rainwater that falls on

the drilling rig deck and other areas such as chemical storage areas and places where equipment

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is exposed will be collected and oil and water separated to meet NPDES permit requirements.  

Based on adherence to permit limits and applicable regulations, little or no impact on water

quality is anticipated.

Other discharges in accordance with the NPDES permit, such as desalination unit brine and

uncontaminated cooling water, fire water, and ballast water, are expected to be diluted rapidly,

resulting in little or no impact on water quality.

Impacts of a Small Fuel Spill

Potential impacts of a small spill on water quality are expected to be consistent with those

analyzed and discussed in recent EISs (MMS, 2007b, 2008).  The probability of a small spill would

be minimized by Hess’s preventative measures during routine operations, including fuel

transfer.    In the unlikely event of a spill, implementation of Hess’s OSRP will potentially help

mitigate and reduce the impacts.  SEP Appendix I provides detail on spill response measures in

addition to the summary information provided in this EIA.  Given the open ocean location of the

lease area, the extent and duration of water quality impacts from a small spill would not be

significant.

A small fuel spill in offshore waters would produce a slick on the water surface and increase the

concentrations of petroleum hydrocarbons and their degradation products.    The extent and

persistence of impacts would depend on the meteorological and oceanographic conditions at

the time and the effectiveness of spill response measures.  However, it is estimated that over

90% of a small diesel spill would be evaporated or dispersed within 24 hours (see Section A.9.2).  

The area of the sea surface with diesel fuel on it would range from 0.5 to 5 ha (1.2 to 12 ac),

depending on sea state and weather conditions.

The water‐soluble fractions of diesel are dominated by two‐ and three‐ringed PAHs, which are

moderately volatile (NRC, 2003).    The constituents of these oils are light to intermediate in

molecular weight and can be readily degraded by aerobic microbial oxidation.  The density of

diesel prevents it from sinking and pooling on the seafloor.    Diesel dispersed in the water

column can adhere to suspended sediments, but this generally occurs only in coastal areas with

high‐suspended solid loads (NRC, 2003) and would not be expected to occur to any appreciable

degree in offshore waters of the Gulf of Mexico.  Diesel oil is readily and completely degraded

by naturally occurring microbes (NOAA, 2006).

A small fuel spill would not affect coastal water quality because the spill would not be expected

to make landfall or reach coastal waters due to both response efforts that would be undertaken

as well as natural attenuation (see Section A.9.2).

Impacts of a Large Oil Spill (WCD)

Potential impacts of a large oil spill on water quality are expected to be consistent with those

analyzed and discussed in the lease sale EISs (MMS, 2007b, 2008).   A large spill would affect

water quality by producing a slick on the water surface and increasing the concentrations of

petroleum hydrocarbons and their degradation products.  The extent and persistence of impacts

would depend on the meteorological and oceanographic conditions at the time and the

effectiveness of spill response measures.  Most of the oil would be expected to form a slick at

the surface, although new information from the Macondo spill indicates that plumes of

submerged oil droplets can be produced when subsea dispersants are applied at the wellhead

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(Camilli et al., 2010; Hazen et al., 2010; Joint Analysis Group, 2010a,b,c).  However, dispersants

would be applied only after approval from the USEPA.  Small droplets in the water may adhere

to suspended sediments and be removed from the water column (Operational Scientific

Advisory Team [OSAT], 2010).

Due to the lease area location (130 miles [209 km] from the nearest shoreline), it is expected

that most water quality impacts would occur in offshore waters, especially in the event of a spill

lasting less than 30 days.

C.2 Seafloor Habitats and Biota

Water depth at the proposed SHLs is approximately 2,623 ft (800 m).  Seafloor conditions at the

proposed wellsites are relatively smooth, sloping at about 4.6° to the south‐southwest.  

Proposed wellsite LL4 lies along the base of a shallow salt topographic high.

Chemosynthetic and deepwater coral communities occur in GB 386.  Based on the site clearance

assessment by Geoscience Earth & Marine Services, Inc. (GEMS) , there is no evidence of

features that may support chemosynthetic or other benthic communities within 610 m (2,000 ft)

of the proposed wells in GB 386 (GEMS, 2011).

C.2.1 Soft Bottom Benthic Communities

There are no site‐specific benthic community data from the lease area.  However, data from the

recent Northern Gulf of Mexico Continental Slope Habitats and Benthic Ecology Study

(Wei, 2006; Rowe and Kennicutt, 2009) can be used to describe typical benthic communities in

the region.  Table 5 summarizes data from several nearby stations in similar water depths.

Table 5. Benthic community data from stations near the lease area and in similar water depths

sampled during the Northern Gulf of Mexico Continental Slope Habitats and Benthic

Ecology Study (From: Rowe and Kennicutt, 2009).

Abundance

Station Water Depth

(m) Meiofauna

(no./m2)

Macroinfauna

(no./m2)

Megafauna

(no./ha)

BH 545 407,852 3,143 3,009

W‐2 625 263,315 3,662 442

W‐3 875 262,642 1,883 0

Meiofaunal and megafaunal abundance from Rowe and Kennicutt (2009); macroinfaunal abundance from

Wei (2006).

Densities of meiofauna (animals passing through a 0.5‐mm sieve but retained on a 0.062‐mm

sieve) in water depths of the lease area typically range from about 263,000 to

886,000 individuals/m2 (Rowe and Kennicutt, 2009).    Meiofaunal densities at nearby stations

(Table 5) are within this range.  Nematodes and harpacticoid copepods were the two dominant

groups in the meiofauna, accounting for about 90% of total abundance.

The benthic macroinfauna is characterized by small mean individual sizes and low densities,

both of which are a reflection of the meager primary production in Gulf of Mexico surface

waters (Wei, 2006).  Densities decrease exponentially with water depth.  Based on an equation

presented by Wei (2006), macroinfaunal densities in the water depths of the lease area are

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expected to be approximately 3,800 individuals/m2; however, actual densities are highly

variable.    Macroinfaunal densities at the stations listed in Table 5 range from

1,883 to 3,662 individuals/m2

.

Polychaetes are typically the most abundant macroinfaunal group on the northern Gulf of

Mexico continental slope, followed by amphipods, tanaids, bivalves, and isopods.  Wei (2006)

recognized four depth‐dependent faunal zones (1 through 4), two of which are divided

horizontally.  GB 386 is located in Zone 1, which includes the upper Texas‐Louisiana Slope, the

west flank of the upper Mississippi Fan, the head of Mississippi Canyon, and upper West Florida

Terrace, with stations ranging in depth from 699 to 5,158 ft (213 to 1,572 m).    The most

abundant species in Zone 1 were the polychaetes Litocorsa antennata, Prionospio cirrifera, and

Aricidea suecica; the bivalve Heterodonta sp. A; and the amphipod Ampelisca mississippina.  

Megafaunal densities from nearby stations ranged from 0 to 3,009 individuals/ha (Table 5).  

Common megafauna included motile groups such as decapods, ophiuroids, holothurians, and

demersal fishes, as well as sessile groups such as sponges and anemones.

Bacteria are also an important component in terms of biomass and cycling of organic carbon

(Cruz‐Kaegi, 1998).    Bacterial biomass at the depth range of the lease area typically is about

1 to 2 g C/m2 in the top 15 cm of sediments (Rowe and Kennicutt, 2009).

IPFs potentially affecting soft bottom benthic communities are physical disturbances to the

seafloor, effluent discharges (drilling muds and cuttings), and a large oil spill (WCD) from a well

blowout at the seafloor.  A small fuel spill would not affect benthic communities because the

diesel would float and dissipate on the sea surface.

Physical Disturbance to the Seafloor

In water depths such as those encountered in the lease area, DP semisubmersibles disturb the

seafloor only around the wellbore (SHL) where the bottom template and BOP are located.  

Depending upon the specific well configuration, this area is generally about 0.25 ha (0.62 ac).

The areal extent of these impacts from a DP drilling rig will be small compared to the lease area

itself, and these types of soft bottom communities are ubiquitous along the northern Gulf of

Mexico continental slope (Gallaway, 1988; Gallaway et al., 2003; Rowe and Kennicutt, 2009).  

Impacts from the physical disturbance of the seafloor during the project will have no significant

impact on soft bottom benthic communities in the region.

Impacts of Effluent Discharges

Drilling mud and cuttings are the only effluents that are likely to affect benthic communities.  

During initial well interval(s) before the marine riser is set, cuttings and seawater‐based “spud

mud” will be released at the seafloor.  Excess cement slurry will also be released at the seafloor

during casing installation for the riserless portion of the drilling operations.    Cement slurry

components typically include cement mix and some of the same chemicals used in water‐based

muds (Boehm et al., 2001).    The main impacts will be burial and smothering of benthic

organisms within several meters to tens of meters around the wellbore.  Soft bottom sediments

disturbed by cuttings, drilling muds, and cement slurry will eventually be recolonized through

larval settlement and migration from adjacent areas.  Because some deep‐sea biota grow and

reproduce slowly, recovery may require several years.

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Discharges of washed SBM cuttings from the rig may affect benthic communities, primarily

within several hundred meters of the wellsite.  The fate and effects of SBM cuttings have been

reviewed by Neff et al. (2000), and monitoring studies have been conducted in the Gulf of

Mexico by Continental Shelf Associates, Inc. (2004, 2006).    In general, washed cuttings with

adhering SBMs tend to clump together and form thick cuttings piles close to the drillsite.  Areas

of SBM cuttings deposition may develop elevated organic carbon concentrations and anoxic

conditions (Continental Shelf Associates, Inc., 2006).    Where SBM cuttings accumulate in

concentrations of approximately 1,000 mg/kg or higher, benthic infaunal communities may be

adversely affected due to both the toxicity of the base fluid and organic enrichment (with

resulting anoxia) (Neff et al., 2000).  Infaunal numbers may increase and diversity may decrease

as opportunistic species that tolerate low oxygen and high H2S predominate (Continental Shelf

Associates, Inc., 2006).   As the base synthetic fluid is decomposed by microbes, the area will

gradually return to pre‐drilling conditions.    Disturbed sediments will be recolonized through

larval settlement and migration from adjacent areas.

The areal extent of impacts from drilling discharges will be small.    Assuming a typical effect

radius of 500 m (1,640 ft), the affected area around each wellsite represents about 3% of the

seafloor within a lease block.  Soft bottom communities are ubiquitous along the northern Gulf

of Mexico continental slope (Gallaway, 1988; Gallaway et al., 2003; Rowe and Kennicutt, 2009).  

Impacts from drilling discharges during this project will have no significant impact on soft

bottom benthic communities in the region.

Impacts of a Large Oil Spill (WCD)

The most likely effects of a subsea blowout on benthic communities would be within a few

hundred meters of the wellsite.    MMS (2007b) estimated that a severe subsurface blowout

could resuspend and disperse sediments within a 300‐m (984‐ft) radius.  While coarse sediments

(sands) would probably settle at a rapid rate within 400 m (1,312 ft) from the blowout site, fine

sediments (silts and clays) could be resuspended for more than 30 days and dispersed over a

much wider area.  Based on previous studies, surface sediments at the project area are assumed

to largely be silt and clay (Rowe and Kennicutt, 2009).

Recent lease sale EISs (MMS, 2007a, 2008) indicated that oil spills would be unlikely to affect

benthic communities beyond the immediate vicinity of the wellhead (i.e., due to physical

impacts of a blowout) because the oil would rise quickly to the sea surface directly over the spill

location.    However, during the Macondo spill, subsurface plumes were reported at a water

depth of about 1,100 m (3,600 ft), extending at least 22 miles (35 km) from the wellsite and

persisting for more than a month (Camilli et al., 2010).    The subsurface plumes apparently

resulted from the use of dispersants at the wellhead (Joint Analysis Group, 2010c).  While the

behavior and impacts of subsurface plumes are not well known, a subsurface plume could

contact the seafloor and affect benthic communities beyond the 300‐m (984‐ft) radius

estimated by MMS (2007a, 2008), depending on its extent, trajectory, and persistence.    This

contact could result in smothering and/or toxicity to benthic organisms.    The affected area

would be recolonized by benthic organisms over a period of months to years (NRC, 2003).

C.2.2 High‐Density Deepwater Benthic Communities

As defined by NTL 2009‐G40, high‐density deepwater benthic communities are features or areas

that could support high‐density chemosynthetic communities, or features or areas that could

support high‐density deepwater corals and other associated high‐density hard bottom

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communities.   Chemosynthetic communities were discovered in the central Gulf of Mexico in

1984 and have been studied extensively (MacDonald, 2002).  Deepwater coral communities are

also known from numerous locations in the Gulf of Mexico (Brooke and Schroeder, 2007;

CSA International, Inc., 2007).    These communities occur almost exclusively on authigenic

carbonates created by chemosynthetic communities.

GB 386 contains chemosynthetic communities and associated deepwater coral.    These

communities include vestimentiferan tube worms and vesicomyid or lucinid clams.   However,

the geohazards assessment of the lease area (GEMS, 2011) did not identify any features that

could support significant high‐density deepwater benthic communities within 610 m (2,000 ft)

of the proposed drilling mud/cuttings discharge locations.

IPFs potentially affecting high‐density deepwater benthic communities are physical disturbances

to the seafloor, effluent discharges (drilling muds and cuttings), and a large oil spill (WCD) from

a well blowout at the seafloor.  A small fuel spill would not affect benthic communities because

the diesel fuel would float and dissipate on the sea surface.

Physical Disturbance to the Seafloor

In water depths such as those that are encountered in the lease area, DP semisubmersibles

disturb the seafloor only around the wellbore (SHL) where the bottom template and BOP are

located.   Depending upon the specific well configuration, this area is generally about 0.25 ha

(0.62 ac).

The areal extent of these impacts will be small, and NTL 2009‐G40 requires that high‐density

deepwater benthic communities and features or areas that could support high‐density

chemosynthetic communities or deepwater coral communities be avoided.   Impacts from the

physical disturbance of the seafloor during this project should have no impact on

chemosynthetic or deepwater coral communities in the region.

Impacts of Effluent Discharges

Chemosynthetic communities have been previously identified in the lease area GB 386.    The

shallow hazards assessment did not identify any features that could support high‐density

deepwater benthic communities within 610 m (2,000 ft) of the proposed drilling locations.  

Monitoring programs on the Gulf of Mexico continental slope have shown that benthic impacts

from drilling discharges typically are concentrated within about 500 m (1,640 ft) of the wellsite,

although detectable deposits may extend beyond this distance (Continental Shelf Associates,

Inc., 2004, 2006; Neff et al., 2005).    Because of the water depth of the lease area, drilling

discharges would be expected to result in thinner, more diffuse accumulations on the seafloor

than those documented in the literature.    Although small amounts of cuttings particles may

reach areas inhabited by high‐density deepwater benthic communities, the discharges are not

expected to result in significant impacts to these communities.

Impacts of a Large Oil Spill (WCD)

Previous analyses (MMS, 2007a, 2008) concluded that oil spills would be unlikely to affect

benthic communities beyond the immediate vicinity of the wellhead (i.e., due to physical

impacts of a blowout) because the oil would rise quickly to the sea surface directly over the spill

location.    However, during the Macondo spill, subsurface plumes were reported at a water

depth of about 1,100 m (3,600 ft), extending at least 22 miles (35 km) from the wellsite and

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persisting for more than a month (Camilli et al., 2010).    The subsurface plumes apparently

resulted from the use of dispersants at the wellhead (Joint Analysis Group, 2010c).  While the

behavior and impacts of subsurface plumes are not well known, a subsurface plume could have

the potential to contact high‐density deepwater benthic communities beyond the 300‐m

(984‐ft) radius estimated by MMS (2007a, 2008), depending on its extent, trajectory, and

persistence.  Potential impacts on sensitive resources would be an integral part of the decision

and approval process for the use of dispersants, and such approval would be obtained from the

USEPA prior to the use of dispersants.

The biological effects and expected fate of the oil remaining in the Gulf of Mexico from the

Deepwater Horizon blowout are still unknown due to the depth and magnitude of the event.  

Hazen et al. (2010) reported changes in plume hydrocarbon composition with distance from the

source.    Incubation experiments with environmental isolates demonstrated

faster‐than‐expected hydrocarbon biodegradation rates at 5°C.  Based on these results, Hazen

et al. (2010) suggested the potential exists for intrinsic bioremediation of the oil plume in the

deep‐water column without substantial oxygen drawdown.

Potential impacts of oil on high‐density deepwater benthic communities are discussed in

MMS (2007b).   Although chemosynthetic communities live among hydrocarbon seeps, natural

seepage is very constant and occurs at low rates compared to the potential rates of oil release

from a blowout.    In addition, seep organisms also require unrestricted access to oxygenated

water at the same time as exposure to hydrocarbon energy sources (MacDonald, 2002).   Oil

droplets or oiled sediment particles could come into contact with chemosynthetic organisms or

deepwater corals.    As discussed by MMS (2007b), impacts could include loss of habitat,

biodiversity, and live coral coverage; destruction of hard substrate; change in sediment

characteristics; and reduction or loss of one or more commercial and recreational fishery

habitats.    Sublethal effects could be long‐lasting and affect the resilience of coral colonies to

natural disturbances (e.g., elevated water temperature and diseases).

The potential for a spill to affect deepwater corals is indicated by preliminary findings from a

recent (October 2010) survey of deepwater coral habitats near the Macondo spill site

(BOEMRE, 2010).    Government and academic researchers were working at a site 1,400 m

(4,600 ft) deep and approximately 7 miles (11 km) southwest of the Macondo wellhead when

they visually observed dead and dying corals with sloughing tissue and discoloration.  Much of

the soft coral observed in an area measuring about 15 by 40 m (50 by 130 ft) was covered by

what appeared to be a brown substance.    Ninety percent of 40 large corals were heavily

affected and showed dead and dying parts and discoloration.    Another site 400 m (1,312 ft)

away had a colony of stony corals similarly affected and partially covered with a similar brown

substance.  Until laboratory analyses are conducted, scientists cannot be certain what caused

the impacts.  Sediment and coral samples were collected with a remotely operated vehicle and

brought to the surface for analyses.  Further testing will also determine if the substance is oil,

and if so, whether it is consistent with the release from the Macondo spill.

C.2.3 Designated Topographic Features

GB 386 is not within or near a designated topographic feature or a no‐activity zone as identified

in NTL 2009‐G39.  The nearest block covered by a topographic features stipulation is GB 121,

located 17 miles (27 km) north of the lease area.

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There are no IPFs associated with either routine operations or accidents that could cause

impacts to designated topographic features because a small fuel spill would float and dissipate

on the surface and would not reach these seafloor features.

In the event of an oil spill from a well blowout, a surface slick would not contact these seafloor

features.  If a subsurface plume were to occur, impacts on these features would be unlikely due

to the difference in water depth.    Near‐bottom currents in the region are predicted to flow

along the isobaths (Nowlin et al., 2001) and typically would not carry a plume up onto the

continental shelf edge.

C.2.4 Pinnacle Trend Area Live Bottoms

The lease area is not covered by the Live Bottom (Pinnacle Trend) Stipulation.   As defined by

NTL 2009‐G39, the nearest pinnacle trend block is MP 290, which lies 255 miles (411 km) to the

northeast of GB 386.

There are no IPFs associated with either routine operations or accidents that could cause

impacts to pinnacle trend area live bottoms due to the distance from the lease area.  A small

fuel spill would float on the surface and would not reach these seafloor features.

In the event of an oil spill from a well blowout, a surface slick would not contact these seafloor

features.  If a subsurface plume were to occur, impacts on these features would be unlikely due

to the distance and the difference in water depth.    Near‐bottom currents in the region are

predicted to flow along the isobaths (Nowlin et al., 2001) and typically would not carry a plume

up onto the continental shelf edge.

C.2.5 Eastern Gulf Live Bottoms

The lease area is not covered by the Live Bottom (Low‐Relief) Stipulation, which applies to

Eastern Gulf of Mexico Planning Area leases in water depths of 100 m (328 ft) or less.    The

nearest block covered by the live bottom stipulation, as defined by NTL 2009‐G39, is

Destin Dome Block 573, approximately 299 miles (481 km) northeast of the lease area.

There are no IPFs associated with either routine operations or accidents that could cause

impacts to eastern Gulf live bottom areas due to the distance from the lease area.  A small fuel

spill would float and dissipate on the surface and would not reach these seafloor features.

In the event of an oil spill from a well blowout, a surface slick would not contact these seafloor

features.  If a subsurface plume were to occur, impacts on these features would be unlikely due

to the distance and the difference in water depth.    Near‐bottom currents in the region are

predicted to flow along the isobaths (Nowlin et al., 2001) and typically would not carry a plume

up onto the continental shelf.

C.3 Threatened, Endangered, and Protected Species and Critical Habitat

This section discusses species listed as endangered or threatened under the Endangered Species

Act (ESA).  In addition, it includes all marine mammal species in the region, which are protected

under the Marine Mammal Protection Act (MMPA).

Endangered or threatened species that may occur in the project area and/or along the northern

Gulf Coast are listed in Table 6.    The table also indicates the location of critical habitat

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(if designated in the Gulf of Mexico).  Critical habitat is defined as (1) specific areas within the

geographical area occupied by the species at the time of listing, if they contain physical or

biological features essential to conservation, and those features may require special

management considerations or protection; and (2) specific areas outside the geographical area

occupied by the species if the agency determines that the area itself is essential for

conservation.    The National Marine Fisheries Service (NMFS) has jurisdiction for ESA‐listed

cetaceans, sea turtles, and fishes in the Gulf of Mexico.    The USFWS has jurisdiction for

ESA‐listed birds and the West Indian manatee.

Table 6. Federally listed endangered and threatened species potentially occurring in the lease

area and along the northern Gulf of Mexico coast.

Potential Presence

Species Scientific Name Status Lease

Area Coastal

Critical Habitat

Designated in

Gulf of Mexico

Marine Mammals

Sperm whale Physeter macrocephalus E X  ‐‐  None

West Indian manatee Trichechus manatus latirostris E  ‐‐  X Florida (Peninsular)

Blue whale Balaenoptera musculus E Xa  ‐‐  None

Fin whale Balaenoptera physalus E Xa  ‐‐  None

Humpback whale Megaptera novaeangliae E Xa  ‐‐  None

North Atlantic right whale Eubalaena glacialis E Xa  ‐‐  None

Sei whale Balaenoptera borealis E Xa  ‐‐  None

Sea Turtles

Loggerhead turtle Caretta caretta T X X None

Green turtle Chelonia mydas T, E

b X X None

Leatherback turtle Dermochelys coriacea E X X None

Hawksbill turtle Eretmochelys imbricata E X X None

Kemp’s ridley turtle Lepidochelys kempii E X X None

Birds

Piping Plover Charadrius melodus T  ‐‐  X

Coastal Texas, Louisiana,

Mississippi, Alabama,

and Florida (Panhandle)

Whooping Crane Grus americana E  ‐‐  X

Coastal Texas

(Aransas National

Wildlife Refuge)

Fishes

Gulf sturgeon Acipenser oxyrinchus desotoi T  ‐‐  X

Coastal Louisiana,

Mississippi, Alabama,

and Florida (Panhandle)

Smalltooth sawfish Pristis pectinata E  ‐‐  X Southwest Florida and

the Florida Keys

Invertebrates

Elkhorn coral Acropora palmata E  ‐‐  X Flower Garden Banks

Terrestrial Mammals

Beach mice (Alabama,

Choctawhatchee,

Perdido Key, St. Andrew)

Peromyscus polionotus E  ‐‐  X Alabama and Florida

(Panhandle) beaches

Abbreviations: E = endangered; T = threatened.   a

   The blue, fin, humpback, North Atlantic right, and sei whales are rare or extralimital in the Gulf of Mexico and are unlikely

to be present in the lease area. b

   The green sea turtle is threatened, except for the Florida breeding population, which is listed as endangered.

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As mandated by the ESA, BOEMRE consulted NMFS and the USFWS on possible and potential

impacts from the proposed leasing in the Gulf of Mexico on endangered/threatened species and

their designated critical habitat (MMS, 2007a,b).  A Biological Assessment was prepared for each

consultation.    The formal ESA consultation with NMFS was concluded with receipt of the

Biological Opinion on 3 July 2007 (NMFS, 2007).    The Biological Opinion concludes that the

proposed lease sales and associated activities in the Five‐Year Leasing Plan for Western and

Central Planning Areas 2007‐2012 are not likely to jeopardize the continued existence of

threatened and endangered species under NMFS jurisdiction or destroy or adversely modify

designated critical habitat.    The informal ESA consultation with USFWS was concluded with a

letter dated 14 September 2007.    The USFWS concurred with MMS’s determination that

proposed actions of the current Five‐Year Leasing Plan were not likely to adversely affect

threatened/endangered species or designated critical habitat under USFWS jurisdiction.  

Following the Macondo spill, BOEMRE requested to reinitiate an ESA consultation with both

NMFS and USFWS on 30 July 2010.    The NMFS responded with a letter to BOEMRE on

24 September 2010, and the USFWS responded with a letter to BOEMRE on 27 September 2010.  

At present, the NMFS and USFWS have placed the consultation process on hold because they

feel the environmental baseline information needs to be updated for the post‐Macondo spill

environment based on the results of the Natural Resource Damage Assessment (NRDA) process.  

The NRDA data have yet to be released, and the existing consultation remains in effect

(BOEM, 2012).  The existing consultation recognizes that BOEM‐required mitigations and other

reasonable and prudent measures should reduce the likelihood of impacts from all

BOEM‐authorized activities in the Gulf of Mexico.

Coastal endangered or threatened species that may occur along the northern Gulf Coast include

the West Indian manatee, Piping Plover, Whooping Crane, Gulf sturgeon, smalltooth sawfish,

and four subspecies of beach mice.  Critical habitat has been designated for all of these species

as indicated in Table 6 and discussed in individual sections.

Two other coastal species (Bald Eagle and Brown Pelican) discussed in the MMS lease sale

EIS (MMS, 2007b) are no longer listed as endangered or threatened.    These are discussed in

Section C.4.2, Shorebirds and Coastal Nesting Birds.

The sperm whale and five species of sea turtles are the only endangered or threatened species

likely to occur at or near the lease area.    No critical habitat has been designated for these

species in the Gulf of Mexico.

There are no other endangered animals or plants in the Gulf of Mexico that are reasonably likely

to be affected by either routine or accidental events.    Other species occurring at certain

locations in the Gulf of Mexico such as the smalltooth sawfish (Pristis pectinata), elkhorn coral

(Acropora palmata), staghorn coral (Acropora cervicornis), and Florida salt marsh vole

(Microtus pennsylvanicus dukecampbelli) are remote from the lease area and highly unlikely to

be affected.

C.3.1 Sperm Whale (Endangered)

The only endangered marine mammal likely to be present at or near the project area is the

sperm whale (Physeter macrocephalus).  Resident populations of sperm whales occur within the

Gulf of Mexico, and a species description is presented in a recent lease sale EIS (MMS, 2007b).  

Gulf of Mexico sperm whales are classified as an endangered species and a “strategic stock”

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(defined as a stock that may have unsustainable human‐caused impacts) by NOAA Fisheries

(Waring et al., 2009).  No critical habitat for the sperm whale has been designated in the Gulf of

Mexico.

The distribution of sperm whales in the Gulf of Mexico is correlated with mesoscale physical

features such as eddies associated with the Loop Current (Jochens et al., 2008).  Sperm whale

populations in the north‐central Gulf of Mexico are present there throughout the year (Davis et

al., 2000).    Results of a multi‐year tracking study show female sperm whales typically

concentrated along the upper continental slope between the 200‐  and 1,000‐m (656‐ and

3,280‐ft) depth contours (Jochens et al., 2008).  Male sperm whales were more variable in their

movements and were documented in water depths greater than 3,000 m (9,843 ft).  Generally,

groups of sperm whales sighted in the Gulf of Mexico during the MMS‐funded Sperm Whale

Seismic Study (SWSS) consisted of mixed‐sex groups comprising adult females and immatures,

and groups of bachelor males.    Typical group size for mixed groups was 10 individuals

(Jochens et al., 2008).  SWSS results show that sperm whales transit through the vicinity of the

lease area.    Movements of satellite‐tracked individuals suggest that this area of the Gulf

continental slope is within the home range of the Gulf of Mexico population (within the

95% utilization distribution) (Jochens et al., 2008).

IPFs potentially affecting sperm whales include drilling rig presence, noise, and lights; support

vessel and helicopter traffic; and two types of accidents – a small fuel spill or a large oil spill

(WCD).  Effluent discharges are likely to have negligible impacts on sperm whales due to rapid

dispersion, the small area of ocean affected, the intermittent nature of the discharges, and the

mobility of these marine mammals.    Compliance with NTL 2012‐BSEE‐G01 will minimize the

potential for marine debris‐related impacts on sperm whales.

Current threats to sperm whale populations worldwide are discussed in a final recovery plan for

the sperm whale recently published by NOAA (NMFS, 2010a).  Threats are defined as “any factor

that could represent an impediment to recovery,” and include fisheries interactions,

anthropogenic noise, vessel interactions, contaminants and pollutants, disease, injury from

marine debris, research, predation and natural mortality, direct harvest, competition for

resources, loss of prey base due to climate change and ecosystem change, and cable laying.  In

the Gulf of Mexico, the impacts from many of these threats are identified as either low or

unknown (BOEM, 2011, 2012).

Impacts of Drilling Rig Presence, Noise, and Lights

Noise from routine drilling activities has the potential to disturb sperm whales.  Sperm whales

appear to have good low‐frequency hearing, but the available data do not indicate a consistent

response to anthropogenic noise (Jochens et al., 2008).    Noise associated with drilling is

relatively weak in intensity, and an individual animal’s noise exposure would be transient.  There

are other OCS facilities and activities near the lease area, and the region as a whole has a large

number of similar sources.  Due to the limited scope and short duration of drilling activities, this

project would represent a small temporary contribution to the overall noise regime.

NMFS analyzed the potential for impacts of drilling‐related noise on sperm whales in its

Biological Opinion for the Gulf of Mexico Oil and Gas Activities: Five‐Year Leasing Plan for

Western and Central Planning Areas 2007‐2012 (NMFS, 2007).    The analysis noted that

semisubmersible drilling rigs emit low sound source levels and concluded that drilling is not

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expected to produce amplitudes sufficient to cause hearing or behavioral effects in sperm

whales; therefore, these effects are insignificant (NMFS, 2007).

Drilling rig lighting and rig presence are not identified as IPFs for sperm whales in recent lease

sale EISs (MMS, 2007b, 2008) or the NMFS (2007) Biological Opinion.

Impacts of Support Vessel and Helicopter Traffic

Support vessel traffic has the potential to disturb sperm whales, and there is also a risk of vessel

strikes, which are identified as a threat in the recovery plan for this species (NMFS, 2010a).  Data

concerning the frequency of vessel strikes are presented in a recent lease sale EIS (MMS,

2007b).  To reduce the potential for vessel strikes, BOEM and BSEE issued NTL 2012‐JOINT‐G01,

which recommends protected species identification training and that vessel operators and

crews maintain a vigilant watch for marine mammals and slow down or stop their vessel to

avoid striking protected species, and requires operators to report sightings of any injured or

dead protected species.  When whales are sighted, vessel operators and crews are required to

attempt to maintain a distance of 91 m (300 ft) or greater whenever possible.  Vessel operators

are required to reduce vessel speed to 10 knots or less, when safety permits, when mother/calf

pairs, pods, or large assemblages of cetaceans are observed near an underway vessel.  

Compliance with this NTL will minimize the likelihood of vessel strikes as well as reduce the

chance for disturbing sperm whales.

NMFS (2007) analyzed the potential for vessel strikes and harassment of sperm whales.  With

implementation of the mitigation measures in NTL 2012‐JOINT‐G01, the likelihood of collisions

between vessels and sperm whales would be reduced to insignificant levels.  NMFS concluded

that the observed avoidance of passing vessels by sperm whales is an advantageous response to

avoid a potential threat and is not expected to result in any significant effect on migration,

breathing, nursing, breeding, feeding, or sheltering to individuals, or have any consequences at

the population level.    With implementation of the vessel strike avoidance measures

requirement to maintain a distance of 91 m (300 ft) from sperm whales, the NMFS concluded

that the potential for harassment of sperm whales would be reduced to discountable levels.

Helicopter traffic also has the potential to disturb sperm whales.    Smultea et al. (2008)

documented responses of sperm whales offshore Hawaii to fixed‐wing aircraft flying at an

altitude of 245 m (800 ft).    A reaction to the initial pass of the aircraft was observed during

3 (12%) of 24 sightings.  All three reactions consisted of a hasty dive and occurred at less than

360 m (1,180 ft) lateral distance from the aircraft.  Additional reactions were seen when aircraft

circled certain whales to make further observations.    Based on other studies of cetacean

responses to sound, the authors concluded that the observed reactions to brief overflights by

the aircraft were short‐term and probably of no long‐term biological significance.

While flying offshore in the Gulf of Mexico, helicopters maintain altitudes above 213 m (700 ft)

during transit to and from the working area.  In the event that a whale is seen during transit, the

helicopter will not approach or circle the animals.  Although responses are possible based on the

Smultea et al. (2008) study, the NMFS (2007) concluded that this altitude would minimize the

potential for disturbing sperm whales.  Therefore, no significant impacts are expected.

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Impacts of a Small Fuel Spill

Potential spill impacts on marine mammals including sperm whales are discussed in recent lease

sale EISs (MMS, 2007b, 2008) and by NMFS (2007).    Oil impacts on marine mammals are

discussed by Geraci and St. Aubin (1990).  For this SEP, there are no unique site‐specific issues

with respect to spill impacts on these animals that were not analyzed in the previous

documents.

The probability of a fuel spill will be minimized by Hess’s preventative measures during routine

operations including fuel transfer.    In the unlikely event of a spill, implementation of Hess’s

OSRP will mitigate and lessen the potential for impacts on sperm whales.  Given the open ocean

location of the lease area, the duration of a small spill and opportunity for impacts to occur

would be very brief.

A small fuel spill in offshore waters would produce a slick on the water surface and increase the

concentrations of petroleum hydrocarbons and their degradation products.    The extent and

persistence of impacts would depend on the meteorological and oceanographic conditions at

the time and the effectiveness of spill response measures.  Section A.9.2 discusses the likely fate

of a small fuel spill and indicates that over 90% would be evaporated or dispersed naturally

within 24 hours.  The area of the sea surface with diesel fuel on it would range from 0.5 to 5 ha

(1.2 to 12 ac), depending on sea state and weather conditions.

Direct physical and physiological effects of exposure to diesel fuel could include skin irritation,

inflammation, or necrosis; chemical burns of skin, eyes, and mucous membranes; inhalation of

toxic fumes; ingestion of oil directly or via contaminated prey; and stress from the activities and

noise of response vessels and aircraft (Marine Mammal Commission [MMC], 2010).  However,

due to the limited areal extent and short duration of water quality impacts from a small fuel

spill, as well as the mobility of sperm whales, no significant impacts would be expected.

Impacts of a Large Oil Spill (WCD)

Potential spill impacts on marine mammals including sperm whales are discussed in recent EISs

(MMS, 2007b, 2008) and by NMFS (2007).  For this SEP, there are no unique site‐specific issues

with respect to spill impacts on these animals.

Impacts of oil spills on sperm whales can include direct impacts from oil exposure, as well as

indirect impacts due to response activities and materials (e.g., vessel traffic, noise, and

dispersants) (MMC, 2010).  Direct physical and physiological effects can include skin irritation,

inflammation, or necrosis; chemical burns of skin, eyes, and mucous membranes; inhalation of

toxic fumes; ingestion of oil (and dispersants) directly or via contaminated prey; and stress from

the activities and noise of response vessels and aircraft.  Complications of the above may lead to

dysfunction of immune and reproductive systems, physiological stress, declining physical

condition, and death.    Behavioral responses can include displacement of animals from prime

habitat, disruption of social structure, changing prey availability and foraging distribution

and/or patterns, changing reproductive behavior/productivity, and changing movement

patterns or migration (MMC, 2010).

In the event of a large spill, the level of vessel and aircraft activity associated with spill response

could disturb sperm whales and potentially result in vessel strikes, entanglement, or other injury

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or stress.  Response vessels would operate in accordance with NTL 2012‐JOINT‐G01 to reduce

the potential for striking or disturbing these animals.

C.3.2 West Indian Manatee (Endangered)

Most of the Gulf of Mexico manatee population is located in peninsular Florida (USFWS, 2001).  

Manatee sightings in Louisiana have been increasing as the species extends its presence farther

west of Florida in the warmer months (Wilson, 2003).  A species description is presented in a

recent lease sale EIS (MMS, 2007b) and in the recovery plan for this species (USFWS, 2001).

IPFs potentially affecting manatees include support vessel and helicopter traffic and a large oil

spill (WCD).  A small fuel spill in the lease area would be unlikely to affect manatees, as the lease

area is approximately 130 miles (209 km) from the nearest shoreline (Louisiana).  As explained in

Section A.9.2, a small fuel spill would not be expected to make landfall or reach coastal waters

prior to breaking up.    Compliance with NTL 2012‐BSEE‐G01 will minimize the potential for

marine debris‐related impacts on manatees.

Impacts of Support Vessel and Helicopter Traffic

Support vessel traffic has the potential to disturb manatees, and there is also a risk of vessel

strikes, which are identified as a threat in the recovery plan for this species (USFWS, 2001).  To

reduce the potential for vessel strikes, BOEM and BSEE issued NTL 2012‐JOINT‐G01, which

recommends protected species identification training and that vessel operators and crews

maintain a vigilant watch for marine mammals and slow down or stop their vessel to avoid

striking protected species, and requires operators to report sightings of any injured or dead

protected species.  Compliance with NTL 2012‐JOINT‐G01 will minimize the likelihood of vessel

strikes, and no significant impacts on manatees are expected.

Helicopter traffic also has the potential to disturb manatees.    Rathbun (1988) reported that

manatees were disturbed more by helicopters than by fixed‐wing aircraft; however, the

helicopter was flown at relatively low altitudes of 20 to 160 m (66 to 525 ft).  Helicopters used in

support operations maintain a minimum altitude of 213 m (700 ft) while in transit offshore,

305 m (1,000 ft) over unpopulated areas or across coastlines, and 610 m (2,000 ft) over

populated areas and sensitive habitats such as wildlife refuges and park properties.    This

mitigation measure will minimize the potential for disturbing manatees, and no significant

impacts are expected.

Impacts of a Large Oil Spill (WCD)

In the event that manatees were exposed to oil, effects could include direct impacts from oil

exposure, as well as indirect impacts due to response activities and materials (e.g., vessel traffic,

noise, and dispersants) (MMC, 2010).  Direct physical and physiological effects can include skin

irritation, inflammation, or necrosis; chemical burns of skin, eyes, and mucous membranes;

inhalation of toxic fumes; ingestion of oil (and dispersants) directly or via contaminated prey

(or contaminated vegetation, in the case of manatees); and stress from the activities and noise

of response vessels and aircraft.  Complications of the above may lead to dysfunction of immune

and reproductive systems, physiological stress, declining physical condition, and death.  

Behavioral responses can include displacement of animals from prime habitat, disruption of

social structure, changing prey availability and foraging distribution and/or patterns, changing

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reproductive behavior/productivity, and changing movement patterns or migration

(MMC, 2010).

In the event that a large oil spill reached coastal waters where manatees were present, the level

of vessel and aircraft activity associated with spill response could disturb manatees and

potentially result in vessel strikes, entanglement, or other injury or stress.    Response vessels

would operate in accordance with NTL 2012‐JOINT‐G01 to reduce the potential for striking or

disturbing these animals, and therefore no significant impacts are expected.

C.3.3 Endangered Mysticete Whales

Five endangered mysticete whales (blue whale, fin whale, humpback whale, North Atlantic right

whale, and sei whale) also have been reported from the Gulf of Mexico but are considered rare

or extralimital there (Würsig et al., 2000).   No critical habitat has been designated for these

species in the Gulf of Mexico.

Due to the rare occurrence of these whales in the Gulf of Mexico and the limited scope and

duration of the project, it is highly unlikely that any endangered mysticete would come into

contact with any project activities, either routine operations or accidents.  NMFS did not include

any of these mysticete whales as affected species in its Biological Opinion (NMFS, 2007).  

Potential impacts are analyzed in recent lease sale EISs (MMS, 2007b, 2008), and those analyses

are incorporated by reference.    If any of these whales were present in the area, potential

impacts would be the same as those discussed below in Section C.3.4.

C.3.4 Non‐Endangered Marine Mammals (Protected)

Excluding the seven endangered species that have been cited previously, there are 22 additional

species of marine mammals that may be found in the Gulf of Mexico.  This includes two species

of mysticete whales, dwarf and pygmy sperm whales, four species of beaked whales, and

14 species of delphinids.    The most common non‐endangered cetaceans in the deepwater

environment are odontocetes such as the pantropical spotted dolphin, spinner dolphin, and

Clymene dolphin.    A brief summary is presented below, and additional information on these

groups is presented in a recent lease sale EIS (MMS, 2007b).

Mysticete whales.  Two species of non‐endangered mysticete whales are known from the Gulf

of Mexico.  The Bryde’s whale (Balaenoptera edeni) has been sighted most frequently along the

100‐m (328‐ft) isobath (Davis and Fargion, 1996; Davis et al., 2000).  Most sightings have been

made in the DeSoto Canyon region and off western Florida, although there have been some in

the west‐central portion of the northeastern Gulf.    The minke whale (Balaenoptera

acutorostrata) is considered rare in the Gulf of Mexico, with the only confirmed records coming

from strandings (Würsig et al., 2000).   Based on the available data, it is possible that Bryde’s

whales could occur in the lease area.

Dwarf and pygmy sperm whales.    At sea, it is difficult to differentiate dwarf sperm whales

(Kogia sima) from pygmy sperm whales (Kogia breviceps), and sightings are often grouped

together as Kogia spp.    Both species have a worldwide distribution in temperate to tropical

waters.  In the Gulf of Mexico, both species occur primarily along the continental shelf edge and

in deeper waters off the continental shelf (Mullin et al., 1991).  Either species could occur in the

lease area.

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Beaked whales.  Four species of beaked whales are known from the Gulf of Mexico.  They are

Blainville’s beaked whale (Mesoplodon densirostris), Cuvier’s beaked whale (Ziphius cavirostris),

Sowerby’s beaked whale (Mesoplodon bidens), and Gervais’ beaked whale (Mesoplodon

europaeus).  Stranding records in the Gulf of Mexico suggest that Gervais’ beaked whale is the

most common and Sowerby’s is extralimital.    Due to the difficulties of at‐sea identification,

beaked whales in the Gulf of Mexico are identified either as Cuvier’s beaked whales or are

grouped into an undifferentiated complex (Mesoplodon spp. and Ziphius spp.).  In the northern

Gulf of Mexico, they are broadly distributed in water depths greater than 1,000 m (3,281 ft) over

lower slope and abyssal landscapes (Davis et al., 2000).  Any of these species could occur in the

lease area.

Delphinids.  Fourteen species of delphinids are known from the Gulf of Mexico: Atlantic spotted

dolphin (Stenella frontalis), bottlenose dolphin (Tursiops truncatus), Clymene dolphin

(Stenella clymene), false killer whale (Pseudorca crassidens), Fraser’s dolphin (Lagenodelphis

hosei), killer whale (Orcinus orca), melon‐headed whale (Peponocephala electra), pantropical

spotted dolphin (Stenella attenuata), pygmy killer whale (Feresa attenuata), short‐finned pilot

whale (Globicephala macrorhynchus), Risso’s dolphin (Grampus griseus), rough‐toothed dolphin

(Steno bredanensis), spinner dolphin (Stenella longirostris), and striped dolphin

(Stenella coeruleoalba).  Any of these species could occur in the lease area.  The most common

non‐endangered cetaceans in the deepwater environment are the pantropical spotted dolphin,

spinner dolphin, and Clymene dolphin.

IPFs potentially affecting non‐endangered marine mammals include drilling rig presence, noise,

and lights; support vessel and helicopter traffic; and two types of accidents: a small fuel spill and

a large oil spill (WCD).    Effluent discharges are likely to have negligible impacts on marine

mammals due to rapid dispersion, the small area of ocean affected, the intermittent nature of

the discharges, and the mobility of marine mammals.  Compliance with NTL 2012‐BSEE‐G01 will

minimize the potential for marine debris‐related impacts on marine mammals.

Impacts of Drilling Rig Presence, Noise, and Lights

Noise from routine drilling activities has the potential to disturb marine mammals.    Most

odontocetes (toothed whales and dolphins) use higher frequency sounds than those produced

by OCS drilling activities (Richardson et al., 1995).   Noise associated with drilling is relatively

weak in intensity, and an individual animal’s noise exposure would be transient.  There are other

OCS facilities and activities near the lease area, and the region as a whole has a large number of

similar sources.   Due to the limited scope and short duration of drilling activities, this project

would represent a small temporary contribution to the overall noise regime, and any short‐term

impacts are not expected to be biologically significant to marine mammal populations.

Drilling rig lighting and rig presence are not identified as IPFs for marine mammals in lease sale

EISs (MMS, 2007b, 2008).

Impacts of Support Vessel and Helicopter Traffic

Support vessel traffic has the potential to disturb marine mammals, and there is also a risk of

vessel strikes.  Data concerning the frequency of vessel strikes are presented in a recent lease

sale EIS (MMS, 2007b).  To reduce the potential for vessel strikes, BOEM and BSEE issued NTL

2012‐JOINT‐G01, which recommends protected species identification training and that vessel

operators and crews maintain a vigilant watch for marine mammals and slow down or stop their

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vessel to avoid striking protected species, and requires operators to report sightings of any

injured or dead protected species.    Vessel operators and crews are required to attempt to

maintain a distance of 91 m (300 ft) or greater when whales are sighted and 45 m (150 ft) when

small cetaceans are sighted.   When cetaceans are sighted while a vessel is underway, vessels

must attempt to remain parallel to the animal’s course and avoid excessive speed or abrupt

changes in direction until the cetacean has left the area.    Vessel operators are required to

reduce vessel speed to 10 knots or less when mother/calf pairs, pods, or large assemblages of

cetaceans are observed near an underway vessel, when safety permits.    Compliance with

NTL 2012‐JOINT‐G01 will minimize the likelihood of vessel strikes as well as reduce the chance

for disturbing marine mammals, and therefore no significant impacts are expected.

Aircraft traffic also has the potential to disturb marine mammals (Würsig et al., 1998).  However,

while flying offshore, helicopters maintain altitudes above 213 m (700 ft) during transit to and

from the working area.  This altitude will minimize the potential for disturbing marine mammals,

and no significant impacts are expected (MMS, 2007b).

Impacts of a Small Fuel Spill

Potential spill impacts on marine mammals are discussed in recent EISs (MMS, 2007b, 2008),

and oil impacts on marine mammals in general are discussed by Geraci and St. Aubin (1990).  For

this SEP, there are no unique site‐specific issues with respect to spill impacts on these animals.

The probability of a fuel spill will be minimized by Hess’s preventative measures during fuel

transfer.  In the unlikely event of a spill, implementation of Hess’s OSRP is expected to lessen

the potential for impacts on marine mammals.  SEP Appendix I provides detail on spill response

measures, along with a summary of those measures in this EIA.  Given the open ocean location

of the lease area, the limited duration of a small spill, and response efforts, it is expected that

any impacts would be brief and minimal.

A small fuel spill in offshore waters would produce a slick on the water surface and increase the

concentrations of petroleum hydrocarbons and their degradation products.    The extent and

persistence of impacts would depend on the meteorological and oceanographic conditions at

the time and the effectiveness of spill response measures.  Section A.9.2 discusses the likely fate

of a small fuel spill and indicates that over 90% would be evaporated or dispersed naturally

within 24 hours.  The area of the sea surface with diesel fuel on it would range from 0.5 to 5 ha

(1.2 to 12 ac), depending on sea state and weather conditions.

Direct physical and physiological effects of exposure to diesel fuel could include skin irritation,

inflammation, or necrosis; chemical burns of skin, eyes, and mucous membranes; inhalation of

toxic fumes; ingestion of oil directly or via contaminated prey; and stress from the activities and

noise of response vessels and aircraft (MMC, 2010).  However, due to the limited areal extent

and short duration of water quality impacts from a small fuel spill, as well as the mobility of

marine mammals, no significant impacts would be expected.

Impacts of a Large Oil Spill (WCD)

Potential spill impacts on marine mammals are discussed in MMS (2000, 2007b, 2008).  For this

SEP, there are no unique site‐specific issues.    Impacts of oil spills on marine mammals can

include direct impacts from oil exposure, as well as indirect impacts due to response activities

and materials (e.g., vessel traffic, noise, and dispersants) (MMC, 2010).    Direct physical and

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physiological effects can include skin irritation, inflammation, or necrosis; chemical burns of

skin, eyes, and mucous membranes; inhalation of toxic fumes; ingestion of oil (and dispersants)

directly or via contaminated prey (or contaminated vegetation, in the case of manatees); and

stress from the activities and noise of response vessels and aircraft.  Complications of the above

may lead to dysfunction of immune and reproductive systems, physiological stress, declining

physical condition, and death.  Behavioral responses can include displacement of animals from

prime habitat, disruption of social structure, changing prey availability and foraging distribution

and/or patterns, changing reproductive behavior/productivity, and changing movement

patterns or migration (MMC, 2010).

In the event of a large spill, the level of vessel and aircraft activity associated with spill response

could disturb marine mammals and potentially result in vessel strikes, entanglement, or other

injury or stress.    Response vessels would operate in accordance with NTL 2012‐JOINT‐G01 to

reduce the potential for striking or disturbing these animals, and therefore no significant

impacts are expected.

C.3.5 Sea Turtles (Endangered/Threatened)

Five species of endangered or threatened sea turtles may be found near the lease area.  

Leatherback (Dermochelys coriacea), Kemp's ridley (Lepidochelys kempii), and hawksbill

(Eretmochelys imbricata) turtles are endangered.    The loggerhead turtle (Caretta caretta) is a

threatened species.   The green turtle (Chelonia mydas) is listed as threatened, except for the

Florida and Pacific coast of Mexico breeding populations, which are listed as endangered.  

Species descriptions are presented in the MMS (2007b).

BOEM has reexamined the impacts analysis presented in MMS (2007b, 2008) for the five sea

turtles species that inhabit the Gulf of Mexico based on additional information and in

consideration of the Macondo oil spill event.  Information from the five‐year status reviews for

federally listed sea turtles in the Gulf of Mexico has been incorporated in BOEM (2011, 2012).  

However, no new information from previous EISs was found that would alter the potential

impacts on sea turtles.  In most foreseeable cases, exposure to hydrocarbons persisting in the

sea following the dispersal of an oil slick will result in sublethal impacts (e.g., decreased health,

reproductive fitness, and longevity; and increased vulnerability to disease) to sea turtles.

Leatherbacks and loggerheads are the most likely species to be present near the lease area as

adults.    Green, hawksbill, and Kemp’s ridley turtles are typically inner shelf and nearshore

species, unlikely to occur near the lease area as adults.  Hatchlings or juveniles of any of the sea

turtle species may be present in deepwater areas, including the lease area, where they may be

associated with Sargassum and other flotsam.

Sea turtle nesting in the northern Gulf of Mexico can be summarized by species as follows:

 Loggerhead turtles – Loggerheads nest in significant numbers along the Florida Panhandle

and, to a lesser extent, from Texas through Alabama (MMS, 2007b).  The nearest significant

nesting area of loggerhead turtles is found in Louisiana, on beaches within the Breton NWR;

 Green and leatherback turtles – Green and leatherback turtles infrequently nest on Florida

Panhandle beaches (Florida Fish and Wildlife Conservation Commission, 2011);

 Kemp’s ridley turtles – The main Kemp’s ridley nesting site is Rancho Nuevo beach,

Tamaulipas, Mexico (NMFS et al., 2011).    Kemp’s ridley turtles typically do not nest

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anywhere near the project area, although there have been occasional reports of

Kemp’s ridleys nesting in Alabama (Share the Beach, 2010); and

 Hawksbill turtles – Hawksbills typically do not nest anywhere near the project area.

IPFs potentially affecting sea turtles include drilling rig presence, noise, and lights; support

vessel and helicopter traffic; and two types of accidents: a small fuel spill and a large oil spill

(WCD).    Effluent discharges are likely to have negligible impacts on sea turtles due to rapid

dispersion, the small area of ocean affected, and the intermittent nature of the discharges.  

Compliance with NTL 2012‐BSEE‐G01 will minimize the potential for marine debris‐related

impacts on sea turtles.

Impacts of Drilling Rig Presence, Noise, and Lights  

Offshore drilling activities produce a broad array of sounds at frequencies and intensities that

may be detected by sea turtles (Geraci and St. Aubin, 1987).    Potential impacts may include

behavioral disruption and temporary or permanent displacement from the area near the sound

source.    Certain sea turtles, especially loggerheads, may be attracted to offshore structures

(Lohoefener et al., 1990) and thus may be more susceptible to impacts from sounds produced

during routine operations.   Helicopters and service vessels may also affect sea turtles due to

machinery noise and/or visual disturbances.    The most likely impacts would be short‐term

behavioral changes such as diving and evasive swimming, disruption of activities, or departure

from the area.    Due to the limited scope and short duration of drilling activities, these

short‐term impacts are not expected to be biologically significant to sea turtle populations.

Artificial lighting can disrupt the nocturnal orientation of sea turtle hatchlings (Witherington,

1997; Tuxbury and Salmon, 2005).  However, hatchlings may rely less on light cues when they

are offshore than when they are emerging on the beach (Salmon and Wyneken, 1990).    The

NMFS (2007) concluded that the effects of lighting from offshore structures on sea turtles are

insignificant.

Support Vessel and Helicopter Traffic

Support vessel traffic has the potential to disturb sea turtles, and there is also a risk of vessel

strikes.  Data show that vessel traffic is one cause of sea turtle mortality in the Gulf of Mexico

(Lutcavage et al., 1997).  While adult sea turtles are visible at the surface during the day and in

clear weather, they can be difficult to spot from a moving vessel when resting below the water

surface, during nighttime, or during periods of inclement weather.  To reduce the potential for

vessel strikes, BOEM and BSEE issued NTL 2012‐JOINT‐G01, which recommends protected

species identification training and that vessel operators and crews maintain a vigilant watch for

sea turtles and slow down or stop their vessel to avoid striking protected species, and requires

operators to report sightings of any injured or dead protected species.   When sea turtles are

sighted, vessel operators and crews are required to attempt to maintain a distance of 45 m

(150 ft) or greater whenever possible.  Compliance with this NTL will minimize the likelihood of

vessel strikes as well as reduce the chance for disturbing sea turtles (NMFS, 2007).

Helicopter traffic also has the potential to disturb sea turtles.  However, while flying offshore,

helicopters maintain altitudes above 213 m (700 ft) during transit to and from the working area.  

This altitude will minimize the potential for disturbing sea turtles, and no significant impacts are

expected.

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Impacts of a Small Fuel Spill

Potential spill impacts on sea turtles are discussed in recent EISs (MMS, 2007b, 2008) and the

NMFS Biological Opinion (NMFS, 2007).    For this SEP, there are no unique site‐specific issues

with respect to spill impacts on these animals.

The probability of a fuel spill will be minimized by Hess’s preventative measures during fuel

transfer.  In the unlikely event of a spill, implementation of Hess’s OSRP is expected to minimize

potential impacts on sea turtles.    SEP Appendix I provides detail on spill response measures.  

Given the open ocean location of the lease area, the duration of a small spill and opportunity for

impacts to occur would be very brief.

A small fuel spill in offshore waters would produce a slick on the water surface and increase the

concentrations of petroleum hydrocarbons and their degradation products.    The extent and

persistence of impacts would depend on the meteorological and oceanographic conditions at

the time and the effectiveness of spill response measures.  Section A.9.2 discusses the likely fate

of a small fuel spill and indicates that over 90% would be evaporated or dispersed naturally

within 24 hours.  The area of the sea surface with diesel fuel on it would range from 0.5 to 5 ha

(1.2 to 12 ac), depending on sea state and weather conditions.

Direct physical and physiological effects of exposure to diesel fuel could include skin irritation,

inflammation, or necrosis; chemical burns of skin, eyes, and mucous membranes; inhalation of

toxic fumes; ingestion of oil directly or via contaminated prey; and stress from the activities and

noise of response vessels and aircraft.    However, due to the limited areal extent and short

duration of water quality impacts from a small fuel spill, no significant impacts would be

expected.

A small fuel spill in the lease area would be unlikely to affect sea turtle nesting beaches, as the

lease area is 130 miles (209 km) from the nearest shoreline (Louisiana).    As explained in

Section A.9.2, a small fuel spill would not be expected to make landfall or reach coastal waters

prior to breaking up.

Impacts of a Large Oil Spill (WCD)

Impacts of oil spills on sea turtles can include direct impacts from oil exposure, as well as

indirect impacts due to response activities and materials (e.g., vessel traffic, noise, and

dispersants).  Direct physical and physiological effects can include skin irritation, inflammation,

or necrosis; chemical burns of skin, eyes, and mucous membranes; inhalation of toxic fumes and

smoke (e.g., from in situ burning of oil); ingestion of oil (and dispersants) directly or via

contaminated food; and stress from the activities and noise of response vessels and aircraft.  

Complications of the above may lead to dysfunction of immune and reproductive systems,

physiological stress, declining physical condition, and death.  Behavioral responses can include

displacement of animals from prime habitat, disruption of social structure, changing food

availability and foraging distribution and/or patterns, changing reproductive

behavior/productivity, and changing movement patterns or migration.  In the unlikely event of a

spill, implementation of Hess’s OSRP is expected to minimize the potential for these types of

impacts on sea turtles.  SEP Appendix I provides detail on spill response measures.

Studies of oil effects on loggerheads in a controlled setting (Lutcavage et al., 1995) suggest that

sea turtles show no avoidance behavior when they encounter an oil slick, and any sea turtle in

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an affected area would be expected to be exposed.  Sea turtles’ diving behaviors also put them

at risk.  Sea turtles rapidly inhale a large volume of air before diving and continually resurface

over time, which may result in repeated exposure to volatile vapors and oiling (NMFS, 2007).

Spilled oil reaching sea turtle nesting beaches could have effects on nesting sea turtles and egg

development (NMFS, 2007).    An oiled beach could affect nest site selection or result in no

nesting at all (e.g., false crawls).  Upon hatching and successfully reaching the water, hatchlings

are subject to the same types of oil spill exposure hazards as adults.  Hatchlings that contact oil

residues while crossing a beach can exhibit a range of effects, from acute toxicity to impaired

movement and normal bodily functions (NMFS, 2007).

In the event of a large spill, the level of vessel and aircraft activity associated with spill response

could disturb sea turtles and potentially result in vessel strikes, entanglement, or other injury or

stress.  Response vessels would operate in accordance with NTL 2012‐JOINT‐G01 to reduce the

potential for striking or disturbing these animals, and therefore no significant impacts are

expected.

C.3.6 Piping Plover (Threatened)

The Piping Plover (Charadrius melodus) is a migratory shorebird that overwinters along the

southeastern U.S. and Gulf of Mexico coasts.  This threatened species is in decline as a result of

hunting, habitat loss and modification, predation, and disease (USFWS, 2003).    Critical

overwintering habitat has been designated, including beaches in Texas, Louisiana, Mississippi,

Alabama, and Florida (Figure 3).    Piping Plovers inhabit coastal sandy beaches and mudflats,

feeding by probing for invertebrates at or just below the surface.  They use beaches adjacent to

foraging areas for roosting and preening (USFWS, 2010a).  A species description is presented in a

recent lease sale EIS (MMS, 2007b).

A large oil spill (WCD) is the only IPF potentially affecting Piping Plovers.    There are no IPFs

associated with routine project activities that could affect these birds.  A small fuel spill in the

lease area would be unlikely to affect Piping Plovers because a small fuel spill would not be

expected to make landfall or reach coastal waters prior to breaking up (see explanation in

Section A.9.2).

Impacts of a Large Oil Spill (WCD)

The lease area is 128 miles (206 km) from the nearest shorelines inhabited by Piping Plovers.  

The revised OSRA results (BOEM, 2011, 2012) summarized in Section A.9.3 (Table 3) predict

there is a 4% probability that in spring, an oil spill in the lease area would reach a shoreline

designated as critical habitat for the wintering Piping Plover within 10 days.    Plovers could

physically oil themselves while foraging on oiled shores or secondarily contaminate themselves

through ingestion of oiled intertidal sediments and prey (MMS, 2007b).  Plovers congregate and

feed along tidally exposed banks and shorelines, following the tide out and foraging at the

water’s edge.  It is possible that some deaths of Piping Plovers could occur, especially if spills

occur during winter months when plovers are most common along the coastal Gulf or if spills

contacted critical habitat.  Impacts could also occur from vehicular traffic on beaches and other

activities associated with spill cleanup.   Hess has extensive resources available to protect and

rehabilitate wildlife in the event of a spill reaching the shoreline, as detailed in the OSRP.

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Figure 3. Location of selected environmental features in relation to the lease area.

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C.3.7 Whooping Crane (Endangered)

The Whooping Crane (Grus americana) is an omnivorous wading bird and an endangered

species.    There are three wild populations in North America (Whooping Crane Eastern

Partnership, 2010).    One population winters along the Texas coast at Aransas NWR and

summers at Wood Buffalo National Park in Canada; this population represents the majority of

the world’s population of free‐ranging Whooping Cranes and reached a record population of

270 at Aransas NWR in December 2008 (Whooping Crane Eastern Partnership, 2010).  

A non‐migrating population has been reintroduced in central Florida, and another reintroduced

population summers in Wisconsin and migrates to the southeastern U.S. for the winter.  

Whooping Cranes breed, migrate, winter, and forage in a variety of habitats, including coastal

marshes and estuaries, inland marshes, lakes, ponds, wet meadows and rivers, and agricultural

fields (USFWS, 2007).   About 9,000 ha (22,240 ac) of salt flats on Aransas NWR and adjacent

islands comprise the principal wintering grounds of the Whooping Crane.    Aransas NWR is

designated as critical habitat for the species (Figure 3).  A species description is presented in a

recent lease sale EIS (MMS, 2007b).

A large oil spill (WCD) is the only IPF potentially affecting Whooping Cranes.  A small fuel spill in

the lease area would also be unlikely to affect Whooping Cranes, due to the distance from

Aransas NWR.  As explained in Section A.9.2, a small fuel spill would not be expected to make

landfall or reach coastal waters prior to breaking up.

Impacts of a Large Oil Spill (WCD)

A large oil spill is unlikely to affect Whooping Cranes as the lease area is approximately

261 miles (420 km) from its critical habitat (Aransas NWR).    The revised OSRA modeling

(BOEM, 2011, 2012) predicts a 3% probability that an oil spill originating in the lease area would

reach the Matagorda Island area of the Aransas NWR in Calhoun County, Texas, within 30 days

and a 17% probability of oil reaching that area in 120 days.

In the event of oil exposure, Whooping Cranes could physically oil themselves while foraging in

oiled areas or secondarily contaminate themselves through ingestion of contaminated shellfish,

frogs, and fishes.  It is possible that some Whooping Crane deaths could occur.  In the event of a

spill, Hess would work with the applicable State and Federal agencies to prevent impacts from a

spill.

C.3.8 Gulf Sturgeon (Threatened)

The Gulf sturgeon (Acipenser oxyrinchus desotoi) is a threatened fish species that inhabits major

rivers and inner shelf waters from the Mississippi River to the Suwannee River, Florida

(Barkuloo, 1988; Wakeford, 2001).  An anadromous fish that migrates from the sea upstream

into coastal rivers to spawn in freshwater, it historically ranged from the Mississippi River to

Charlotte Harbor, Florida (Wakeford, 2001).    Today, this range has contracted to encompass

major rivers and inner shelf waters from the Mississippi River to the Suwannee River, Florida.  

Populations have been depleted or even extirpated throughout this range by fishing, shoreline

development, dam construction, water quality changes, and other factors (Barkuloo, 1988;

Wakeford, 2001).    These declines prompted the listing of the Gulf sturgeon as a threatened

species in 1991.  The best known populations occur in the Apalachicola and Suwannee Rivers in

Florida (Carr, 1996; Sulak and Clugston, 1998), the Choctawhatchee River in Alabama (Fox et al.,

2000), and the Pearl River in Mississippi/Louisiana (Morrow et al., 1998).  Critical habitat in the

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Gulf extends from Lake Borgne, Louisiana (St. Bernard Parish) to Suwannee Sound, Florida

(Levy County) (NMFS, 2010b) (Figure 3).  A species description is presented in a recent lease sale

EIS (MMS, 2007b) and in the recovery plan for this species (USFWS and Gulf States Marine

Fisheries Commission, 1995).

A large oil spill (WCD) is the only IPF potentially affecting Gulf sturgeon.    There are no IPFs

associated with routine project activities that could affect these fish.   A small fuel spill in the

lease area would be unlikely to affect Gulf sturgeon because a small fuel spill would not be

expected to make landfall or reach coastal waters prior to breaking up (see explanation in

Section A.9.2).

Impacts of a Large Oil Spill (WCD)

Potential spill impacts on Gulf sturgeon are discussed in recent lease sale EISs (MMS, 2007b,

2008) and by NMFS (2007).  For this SEP, there are no unique site‐specific issues with respect to

this species.

The lease area is approximately 210 miles (337 km) from the nearest Gulf sturgeon critical

habitat.  The revised OSRA modeling (BOEM, 2011, 2012) predicts that a spill in the lease area

has 1% or less probability of contacting coastal areas inhabited by Gulf sturgeon within

30 or 120 days.

In the event of oil reaching Gulf sturgeon habitat, the fish could be affected by direct ingestion,

ingestion of oiled prey, or the absorption of dissolved petroleum products through the gills.  

Based on the life history of this species, subadult and adult Gulf sturgeon would be most

vulnerable to an estuarine or marine oil spill and would be vulnerable only during winter months

(from 1 September through 30 April) when this species is foraging in estuarine and marine

habitats (NMFS, 2007).

C.3.9 Smalltooth Sawfish (Endangered)

Smalltooth sawfish (Pristis pectinata) are found in the tropical and subtropical Atlantic Ocean.  

In the Western Atlantic they have historically ranged from New York to Brazil, including the Gulf

of Mexico and Caribbean Sea.    This sawfish primarily occurs in estuarine and coastal habitats

such as bays, lagoons, and rivers.  The smalltooth sawfish was listed as endangered under the

ESA on 1 April 2003.  Its critical habitat consists of two units: the Charlotte Harbor Estuary Unit,

which comprises approximately 89,621 ha (221,459 ac) of coastal habitat; and the Ten Thousand

Islands/Everglades Unit, which comprises approximately 250,506 ha (619,013 ac) of coastal

habitat.  The two units are located along the southwestern coast of Florida between Charlotte

Harbor and Florida Bay.

A large oil spill (WCD) is the only IPF potentially affecting smalltooth sawfish.  There are no IPFs

associated with routine project activities that could affect these fish.   A small fuel spill in the

lease area would be unlikely to affect smalltooth sawfish because a small fuel spill would not be

expected to make landfall or reach coastal waters prior to breaking up (see Section A.9.2).

Impacts of a Large Oil Spill (WCD)

Potential spill impacts on smalltooth sawfish are similar to those discussed for other coastal and

estuarine species in recent lease sale EISs (MMS, 2000, 2007b, 2008) and by NMFS (2007) in its

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Biological Opinion.    For this SEP, there are no unique site‐specific issues with respect to this

species.

In the event of oil reaching smalltooth sawfish habitat, the fish could be affected by direct

ingestion, ingestion of oiled prey, or the absorption of dissolved petroleum products through

the gills.

C.3.10 Beach Mice (Endangered)

Four subspecies of endangered beach mice (Peromyscus polionotus) occur on the barrier islands

of Alabama and the Florida Panhandle, i.e., Alabama, Choctawhatchee, Perdido Key, and

St. Andrew beach mice.    Critical habitat has been designated for all four subspecies; Figure 3

shows the critical habitat combined for all four subspecies.  Species descriptions are provided in

a recent lease sale EIS (MMS, 2007b).

A large oil spill (WCD) is the only IPF potentially affecting beach mice.    There are no IPFs

associated with routine project activities that could affect these animals due to the distance

from shore and the lack of any onshore support activities near their habitat.  A small fuel spill in

the lease area would not affect beach mice because a small fuel spill would not be expected to

make landfall or reach coastal waters prior to breaking up (see Section A.9.2).

Impacts of a Large Oil Spill (WCD)

Potential spill impacts on beach mice are discussed in recent lease sale EISs (MMS, 2007b,

2008).  For this SEP, there are no unique site‐specific issues with respect to these species that

were not analyzed in these documents.

The lease area is about 313 miles (504 km) southwest from the nearest beach mouse critical

habitat.    The revised OSRA modeling summarized in Section A.9.3 predicts that a spill in the

lease area has a 1% or less probability of reaching either the Alabama or Florida shorelines

inhabited by beach mice within 120 days.

In the event of oil contacting these beaches, beach mice could experience several types of direct

and indirect impacts.  Contact with spilled oil could cause skin and eye irritation and subsequent

infection; matting of fur; irritation of sweat glands, ear tissues, and throat tissues; disruption of

sight and hearing; asphyxiation from inhalation of fumes; and toxicity from ingestion of oil and

contaminated food.    Indirect impacts could include reduction of food supply, destruction of

habitat, and fouling of nests.  Impacts could also occur from vehicular traffic and other activities

associated with spill cleanup.  However, any such impacts are unlikely due to the distance from

shore and response actions that would occur in the event of a spill.

C.3.11 Elkhorn Coral (Endangered)  

Elkhorn coral (Acropora palmata) is found primarily in shallow waters with temperatures ranging

between 26°C and 30°C (79°F and 86°F) and significant water movement.    Elkhorn coral was

once one of the most abundant coral species in waters ranging from 1 to 5 m (3.3 to 16 ft) deep

in tropical and subtropical waters.  In the northern Gulf, elkhorn coral has been found within the

coral cap region of the Flower Garden Banks National Marine Sanctuary (Flower Garden Banks

National Marine Sanctuary, 2011).

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There are no IPFs associated with routine project activities that could affect this species in the

northern Gulf.  A small fuel spill would not affect elkhorn coral colonies because the oil would

float and dissipate on the sea surface.  A WCD would be unlikely to affect the coral cap region of

the Flower Gardens Bank because of the water depth of the area.  Although subsurface plumes

were reported following the Macondo spill, these plumes resulted from the use of subsea

dispersants at the seafloor.

C.4 Coastal and Marine Birds

C.4.1 Marine Birds

Marine birds include seabirds and other species that may occur in the pelagic environment of

the project area (Clapp et al., 1982a,b, 1983; Peake, 1996; Hess and Ribic, 2000).  Seabirds spend

much of their lives offshore over the open ocean, except during breeding season when they nest

along the coast.  In addition, other birds such as waterfowl, marsh birds, and shorebirds may

occasionally be present over open ocean areas.  No endangered or threatened bird species are

likely to occur at the project area due to the distance from shore.  For a discussion of shorebirds

and coastal nesting birds, see Section C.4.2.

Seabirds of the northern Gulf of Mexico were surveyed from ships during the GulfCet II program.  

Hess and Ribic (2000) reported that terns, storm‐petrels, shearwaters, and jaegers were the

most frequently sighted seabirds in the deepwater area.    From these surveys, four ecological

categories of seabirds were documented in the deepwater areas of the Gulf: summer migrants

(shearwaters, storm petrels, boobies); summer residents that breed in the Gulf (Sooty Tern,

Least Tern, Sandwich Tern, Magnificent Frigatebird); winter residents (gannets, gulls, jaegers);

and permanent resident species (Laughing Gulls, Royal Terns, Bridled Terns) (Hess and Ribic,

2000).

Common seabird species include Wilson’s Storm‐Petrel (Oceanites oceanicus), Magnificent

Frigatebird (Fregata magnificens), Northern Gannet (Morus bassanus), Masked Booby

(Sula dactylatra), Brown Booby (Sula leucogaster), Cory’s Shearwater (Calonectris diomedea),

Greater Shearwater (Puffinus gravis), and Audubon’s Shearwater (Puffinus lherminieri).  Seabirds

are distributed Gulf‐wide and are not specifically associated with the lease area.

Relationships with hydrographic features were found for several seabird species, possibly due to

effects of hydrography on nutrient levels and productivity of surface waters where birds forage.  

The GulfCet II study did not estimate bird densities; however, Powers (1987) indicates that

seabird densities over the open ocean typically are <10 birds/km2

.

Trans‐Gulf migrant birds including shorebirds, wading birds, and terrestrial birds may also be

present in the lease area.    Migrant birds may use offshore structures and rigs for resting,

feeding, or as temporary shelter from inclement weather (Russell, 2005).  Some birds may be

attracted to offshore structures because of the lights and the fish populations that aggregate

around these structures.

IPFs potentially affecting marine and pelagic birds include drilling rig presence, noise, and lights;

support vessel and helicopter traffic; and two types of accidents: a small fuel spill and a large oil

spill (WCD).  Effluent discharges are likely to have negligible impacts on the birds due to rapid

dispersion, the small area of ocean affected, the intermittent nature of the discharges, and the

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mobility of these animals.  Compliance with NTL 2012‐BSEE‐G01 will minimize the potential for

marine debris‐related impacts on birds.

Impacts of Drilling Rig Presence, Noise, and Lights

Birds that frequent rigs may be exposed to contaminants including air pollutants and routine

discharges, but significant impacts are unlikely due to rapid dispersion.    Birds migrating over

water have been known to strike offshore structures, resulting in death or injury (Wiese et al.,

2001; Russell, 2005).  Mortality of migrant birds at tall towers and other land‐based structures

has been reviewed extensively, and the mechanisms involved in rig collisions appear to be

similar.  In some cases, migrants simply do not see a part of the rig until it is too late.  In other

cases, navigation may be disrupted by noise (Russell, 2005).    On the other hand, offshore

structures are suitable stopover habitats for most trans‐Gulf migrant species, and most of the

migrants that stop over on rigs probably benefit from their stay, particularly in spring

(Russell, 2005).  Due to the limited scope and short duration of drilling activities described in this

SEP, any impacts on populations of either seabirds or trans‐Gulf migrant birds are not expected

to be significant.

A study in the North Sea indicated that rig lighting causes circling behavior in various birds,

especially on cloudy nights; apparently the birds’ geomagnetic compass is upset by the red part

of the spectrum from the lights currently in use (Poot et al., 2008).  The numbers varied greatly,

from none at all to some tens of thousands of birds per night per rig, with an apparent effect

radius of up to 3 miles (5 km).  A study in the Gulf of Mexico also noted the phenomenon, but

did not recommend mitigation (Russell, 2005).  Factors to consider in evaluating this impact in

the Gulf of Mexico would include the lower incidence of cloudy and foggy days in the Gulf of

Mexico versus the North Sea.  Due to the limited scope and short duration of drilling activities

proposed in this SEP, lighting impacts, collisions, or other adverse effects are unlikely, and no

significant impacts are expected.

Impacts of Support Vessel and Helicopter Traffic

Support vessels and helicopters are unlikely to significantly disturb pelagic birds in open,

offshore waters.    It is likely that individual birds would experience, at most, only short‐term

behavioral disruption, and the impact would not be significant.

Impacts of a Small Fuel Spill

Potential spill impacts on marine birds are discussed in recent EISs (MMS, 2007b, 2008).  For this

SEP, there are no unique site‐specific issues with respect to spill impacts on these animals.

The probability of a fuel spill will be minimized by Hess’s preventative measures during routine

operations including fuel transfer.    In the unlikely event of a spill, implementation of Hess’s

OSRP will reduce the potential for impacts on marine and pelagic birds.  SEP Appendix I provides

details on spill response measures.    Given the open ocean location of the lease area, the

duration of a small spill and opportunity for impacts to occur would be very brief.

A small fuel spill in offshore waters would produce a slick on the water surface and increase the

concentrations of petroleum hydrocarbons and their degradation products.    The extent and

persistence of impacts would depend on the meteorological and oceanographic conditions at

the time and the effectiveness of spill response measures.  Section A.9.2 discusses the likely fate

of a small fuel spill and indicates that over 90% would be evaporated or dispersed naturally

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within 24 hours.  The area of the sea surface with diesel fuel on it would range from 0.5 to 5 ha

(1.2 to 12 ac), depending on sea state and weather conditions.

Birds exposed to oil on the sea surface could experience direct physical and physiological effects

including skin irritation; chemical burns of skin, eyes, and mucous membranes; and inhalation of

toxic fumes.  Due to the limited areal extent and short duration of water quality impacts from a

small fuel spill, secondary impacts due to ingestion of oil via contaminated prey or reductions in

prey abundance are unlikely.  Due to the low densities of birds in open ocean areas, the small

area affected, and the brief duration of the surface slick, no significant impacts on pelagic birds

would be expected.

Impacts of a Large Oil Spill (WCD)

Potential spill impacts on marine and pelagic birds are discussed in recent EISs (MMS, 2007b,

2008).    For this SEP, there are no unique site‐specific issues with respect to spill impacts on

these animals.

BOEM has reexamined the analyses for coastal and marine birds presented in

MMS (2007b, 2008) and determined that no new information was found that would alter the

potential impacts on marine and pelagic birds (BOEM, 2011, 2012).

Pelagic seabirds could be exposed to oil from a spill at the project area.  Hess and Ribic (2000)

reported that terns, storm‐petrels, shearwaters, and jaegers were the most frequently sighted

seabirds in the deepwater Gulf of Mexico (>200 m).    Powers (1987) indicates that seabird

densities over the open ocean typically are <10 birds/km2

.    The number of pelagic birds that

could be affected in open, offshore waters would depend on the extent and persistence of the

oil slick.

The recent Macondo spill provides relevant information about the species of pelagic birds that

may be affected in the event of a large oil spill.  Birds that have been treated for oiling include

several pelagic species such as the Northern Gannet, Magnificent Frigatebird, and Masked

Booby (USFWS, 2011).  The Northern Gannet is among the species with the largest numbers of

birds affected by the spill.

C.4.2 Shorebirds and Coastal Nesting Birds

Threatened and endangered bird species (Piping Plover and Whooping Crane) have been

discussed previously in Section C.3.    Various species of non‐endangered birds are also found

along the northern Gulf Coast, including diving birds, shorebirds, marsh birds, wading birds, and

waterfowl.    Gulf Coast marshes and beaches also provide important feeding grounds and

nesting habitats.  Species that breed on beaches, flats, dunes, bars, barrier islands, and similar

habitats include the Sandwich Tern, Wilson’s Plover, Black Skimmer, Forster’s Tern, Gull‐billed

Tern, Laughing Gull, Least Tern, and Royal Tern (USFWS, 2010b).    Additional information is

presented in recent lease sale EISs (MMS, 2007b, 2008).

The Brown Pelican (Pelecanus occidentalis) was delisted from Federal endangered status in 2009

(USFWS, 2010c).  However, this species is listed as a species of greatest conservation need by

the State of Mississippi (Mississippi Department of Wildlife, Fisheries and Parks, 2011) and as a

species of special concern by the State of Florida (Florida Fish and Wildlife Conservation

Commission, 2011).    Brown Pelicans inhabit coastal habitats and forage within both coastal

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waters and waters of the inner continental shelf.    Aerial and shipboard surveys, including

GulfCet and GulfCet II, indicate that Brown Pelicans do not occur in deep offshore waters

(Fritts and Reynolds, 1981; Peake, 1996; Hess and Ribic, 2000).   Nearly half the southeastern

population of Brown Pelicans lives in the northern Gulf Coast, generally nesting on protected

islands (USFWS, 2010b).

The Southern Bald Eagle (Haliaeetus leucocephalus) was delisted from its threatened status in

the lower 48 states on 28 June 2007.    The Bald Eagle is a terrestrial raptor widely distributed

across the southern U.S., including coastal habitats along the Gulf of Mexico.  The Gulf Coast is

inhabited by both wintering migrant and resident Bald Eagles (Johnsgard, 1990; Ehrlich et al.,

1992).

IPFs potentially affecting shorebirds and coastal nesting birds include support vessel and

helicopter traffic and a large oil spill (WCD).  A small fuel spill in the lease area would be unlikely

to affect shorebirds or coastal nesting birds, as the lease area is 130 miles (209 km) from the

nearest shoreline.   As explained in Section A.9.2, a small fuel spill would not be expected to

make landfall or reach coastal waters prior to breaking up.  Compliance with NTL 2012‐BSEE‐G01

will minimize the potential for marine debris‐related impacts on shorebirds.

Impacts of Support Vessel and Helicopter Traffic

Support vessels and helicopters will transit coastal areas near Port Fourchon and Galliano,

Louisiana, where shorebirds and coastal nesting birds may be found.    These activities could

periodically disturb individuals or groups of birds within sensitive coastal habitats (e.g., wetlands

that may support feeding, resting, or breeding birds).

Vessel traffic may disturb some foraging and resting birds.    Flushing distances vary between

species and between individuals (Rodgers and Schwikert, 2002).    The disturbances will be

limited to flushing birds away from vessel pathways; known distances are from 20 to 49 m

(65 to 160 ft) for personal watercraft and 23 to 58 m (75 to 190 ft) for an outboard‐powered

boat (Rodgers and Schwikert, 2002).  Flushing distances may be similar or less for the support

vessels to be used for Hess’s project, and some species such as gulls are attracted to boats.  

Support vessels will not approach nesting or breeding areas on the shoreline, so disturbances to

nesting birds, eggs, and chicks is not expected.  Vessel operators will use designated navigation

channels and comply with posted speed and wake restrictions while transiting sensitive inland

waterways.   Due to the limited scope and short duration of drilling activities, any short‐term

impacts are not expected to be biologically significant to coastal bird populations.

Aircraft traffic can cause some disturbance to birds onshore and offshore.  Responses are highly

dependent on the type of aircraft, the bird species, the activities that animals were previously

engaged in, and previous exposures to overflights (Efroymson et al., 2000).  Helicopters seem to

cause the most intense responses over other human disturbances for some species (Bélanger

and Bédard, 1989).    However, Federal Aviation Administration Advisory Circular No. 91‐36D

recommends that pilots maintain a minimum altitude of 610 m (2,000 ft) when flying over

noise‐sensitive areas such as wildlife refuges, parks, and areas with wilderness characteristics.  

This is greater than the distance (slant range) at which aircraft overflights have been reported to

cause behavioral effects on most species of birds studied (Efroymson et al., 2000).  With these

guidelines in effect, it is likely that individual birds would experience, at most, only short‐term

behavioral disruption.

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Impacts of Large Oil Spill (WCD)

Data from the Macondo spill provide additional information about the species of coastal birds

that may be affected in the event of a catastrophic spill of a similar nature and duration.  This

information supplements the analysis presented in the lease sale EIS (MMS, 2007b).  According

to USFWS (2010d) and based on the latest reports, about 5,000 dead birds have been collected

since the spill began, and about 1,900 of the dead animals were visibly oiled.  In addition, over

2,000 oiled birds have been collected alive and about 1,200 released (NMFS, 2010c).  According

to the USFWS (2011), bird species that have been treated for oiling include the following:

 Brown Pelican

 White Pelican

 Masked Booby

 Magnificent Frigatebird

 Laughing Gull

 Herring Gull

 Northern Gannet

 Black Crowned Night Heron

 Tri‐colored Heron

 Green Heron

 Cattle Egret

 Snowy Egret

 Reddish Egret

 Least Bittern

 Common Tern

 Royal Tern

 Caspian Tern

 Sandwich Tern

 Forster’s Tern

 Black Tern

 Gull‐billed Tern

 Least Tern

 Black Skimmer

 Black Oystercatcher

 White Ibis

 Roseate Spoonbill

 Willet

 Sanderling

 Dunlin

 Semipalmated Sandpiper

 Killdeer

 King Rail

 Clapper Rail

 Virginia Rail

According to the USFWS (2010d), species with the largest numbers of dead, oiled birds were

Laughing Gull, Northern Gannet, Brown Pelican, Royal Tern, Black Skimmer, Least Tern,

unidentified Gull, and unidentified Tern.  There are no reports of Bald Eagle oiling.

Coastal birds can be exposed to oil as they float on the water’s surface, dive during foraging, or

wade in oiled coastal waters.  Oiled birds can lose the ability to fly, dive for food, or float on the

water, which could lead to drowning (USFWS, 2010e).  Oil interferes with the water repellency

of feathers and can cause hypothermia in the right conditions.  As birds groom themselves, they

can ingest and inhale the oil on their bodies.  Scavengers such as Bald Eagles and gulls can be

exposed to oil by feeding on carcasses of contaminated fish and wildlife.  While ingestion can kill

animals immediately, more often it results in lung, liver, and kidney damage, which can lead to

death.  Bird eggs may be damaged if an oiled adult sits on the nest.

As noted above, the Brown Pelican was recently removed from the Federal endangered species

list.    Over 300 dead Brown Pelicans were collected in the Gulf following the Macondo spill,

(USFWS, 2010d).  These data indicate that Brown Pelicans may be particularly at risk of oiling in

the event of a catastrophic spill reaching coastal waters.  Issues for Brown Pelicans include direct

contact with oil, disturbance by cleanup activities, and long‐term habitat contamination.

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C.5 Fisheries Resources

C.5.1 Pelagic Communities and Ichthyoplankton

Biggs and Ressler (2000) reviewed the biology of pelagic communities in the deepwater

environment of the northern Gulf of Mexico.    The biological oceanography of the region is

dominated by the influence of the Loop Current, whose surface waters are among the most

oligotrophic in the world’s oceans.    Superimposed on this low‐productivity condition are

productive “hot spots” associated with entrainment of nutrient‐rich Mississippi River water and

mesoscale oceanographic features.    Anticyclonic and cyclonic hydrographic features play an

important role in determining biogeographic patterns and controlling primary productivity in the

northern Gulf of Mexico (Biggs and Ressler, 2000).

Most fishes inhabiting shelf or oceanic waters of the Gulf of Mexico have planktonic eggs and

larvae (Ditty, 1986; Ditty et al., 1988; Richards et al., 1989, 1993).    Pelagic eggs and larvae

become part of the planktonic community for various lengths of time (10 to 100 days,

depending on the species) (MMS, 2007b).

IPFs potentially affecting pelagic communities and ichthyoplankton include drilling rig presence,

noise, and lights; effluent discharges; water intakes; and two types of accidents: a small fuel spill

and a large oil spill (WCD).

Impacts of Drilling Rig Presence, Noise, and Lights

The drilling rig, as a floating structure in the deepwater environment, will act as a fish‐attracting

device (FAD).  In oceanic waters, the FAD effect would be most pronounced for epipelagic fishes

such as tunas, dolphin, billfishes, and jacks, which are commonly attracted to fixed and drifting

surface structures (e.g., Holland et al., 1990; Higashi, 1994; Relini et al., 1994; MMS 2000,

2007b, 2008).    This FAD effect could possibly enhance the feeding of epipelagic predators by

attracting and concentrating smaller fish species.  Because the drilling rig is a single, temporary

structure, impacts on fish populations, whether beneficial or adverse, are considered minor.

Impacts of Effluent Discharges

Treated sanitary and domestic wastes may have a slight effect on the pelagic environment in the

immediate vicinity of these discharges.    These wastes may have elevated levels of nutrients,

organic matter, and chlorine, but should be diluted rapidly to undetectable levels within tens to

hundreds of meters from the source.  Minimal impacts on water quality, plankton, and nekton

are anticipated.

Deck drainage may have a slight effect on the pelagic environment in the immediate vicinity of

these discharges.    Deck drainage from contaminated areas will be passed through an

oil‐and‐water separator prior to release, and discharges will be monitored for visible sheen.  The

discharges may have slightly elevated levels of hydrocarbons but should be diluted rapidly to

undetectable levels within tens to hundreds of meters from the source.   Minimal impacts on

water quality, plankton, and nekton are anticipated.

Other discharges in accordance with the NPDES permit, such as water‐based muds and cuttings,

desalination unit brine and uncontaminated cooling water, fire water, and ballast water are

expected to be diluted rapidly and have little or no impact on water column biota.

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Impacts of Water Intakes

Seawater will be drawn from the ocean for once‐through, non‐contact cooling of machinery

on the drilling rig.   The rig considered for use in this SEP is a “new” facility as defined by the

NPDES permit and will therefore comply with the cooling water intake regulations for Phase III

facilities under Section 316(b) of the Clean Water Act.

The intake of seawater for cooling water will entrain plankton.  The low intake velocity should

allow most strong swimming juvenile fishes and smaller adults to escape entrainment or

impingement.   However, drifting plankton would not be able to escape entrainment with the

exception of a few fast swimming larvae of certain taxonomic groups.    Those organisms

entrained may be stressed or killed, primarily through changes in water temperature during the

route from cooling intake structure to discharge structure and mechanical damage (turbulence

in pumps and condensers).  Due to the limited scope and short duration of drilling activities, any

short‐term impacts of entrainment are not expected to be biologically significant to plankton or

ichthyoplankton populations.

Impacts of a Small Fuel Spill

Potential spill impacts on fisheries resources are discussed in recent EISs (MMS, 2007b, 2008).  

For this SEP, there are no unique site‐specific issues with respect to spill impacts.

The probability of a fuel spill will be minimized by Hess’s preventative measures during routine

operations including fuel transfer.    In the unlikely event of a spill, implementation of Hess’s

OSRP will mitigate the potential for impacts on pelagic communities, including ichthyoplankton.  

SEP Appendix I provides detail on spill response measures.  Given the open ocean location of

the lease area, the duration of a small spill and opportunity for impacts to occur would be very

brief.

A small fuel spill in offshore waters would produce a slick on the water surface and increase the

concentrations of petroleum hydrocarbons and their degradation products.    The extent and

persistence of impacts would depend on the meteorological and oceanographic conditions at

the time and the effectiveness of spill response measures.  Section A.9.2 discusses the likely fate

of a small fuel spill and indicates that over 90% would be evaporated or dispersed naturally

within 24 hours.  The area of the sea surface with diesel fuel on it would range from 0.5 to 5 ha

(1.2 to 12 ac), depending on sea state and weather conditions.

A small fuel spill could have localized impacts on phytoplankton, zooplankton, and nekton.  Due

to the limited areal extent and short duration of water quality impacts, a small fuel spill would

be unlikely to produce detectable impacts on pelagic communities.

Impacts of a Large Oil Spill (WCD)

A large oil spill could affect water column biota including phytoplankton, zooplankton,

ichthyoplankton, and nekton.  A large spill that persisted for weeks or months would be more

likely to affect these communities.   While adult and juvenile fishes may actively avoid a large

spill, planktonic eggs and larvae would be unable to avoid contact.  Eggs and larvae of fishes are

especially vulnerable to oiling because they inhabit the upper layers of the water column and

they will die if exposed to certain toxic fractions of spilled oil.    Impacts potentially would be

greater if local scale currents retained planktonic larval assemblages (and the floating oil slick)

within the same water mass.

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C.5.2 Essential Fish Habitat

Essential Fish Habitat (EFH) is defined as those waters and substrate necessary to fish for

spawning, breeding, feeding, and growth to maturity.    Under the Magnuson‐Stevens Fishery

Conservation and Management Act, as amended, Federal agencies are required to consult on

activities that may adversely affect EFH designated in Fishery Management Plans developed by

the regional Fishery Management Councils.

The Gulf of Mexico Fishery Management Council (GMFMC) has prepared Fishery Management

Plans for corals and coral reefs, shrimps, stone crab, spiny lobster, reef fishes, coastal migratory

pelagic fishes, and red drum.    In 2005, the EFH for these managed species was redefined in

Generic Amendment No. 3 to the various Fishery Management Plans (GMFMC, 2005).  The EFH

for most of these GMFMC‐managed species is on the continental shelf in waters shallower than

183 m (600 ft).  The shelf edge is the outer boundary for coastal migratory pelagic fishes, reef

fishes, and shrimps.    EFH for corals and coral reefs includes some shelf‐edge topographic

features on the Texas‐Louisiana OCS, the nearest of which are in GB 121, located approximately

17 miles (27 km) north of the lease area along the shelf edge south of Louisiana.

Highly migratory pelagic fishes, which occur as transients in the lease area, are the only

remaining group for which EFH has been identified in the deepwater Gulf of Mexico.  Species in

this group, including tunas, swordfishes, billfishes, and sharks, are managed by NMFS.  Highly

migratory species with EFH at or near the lease area include the following species and life

stages:  

 Blue marlin (juveniles, adults)

 White marlin (juveniles, adults)

 Skipjack tuna (spawning, juveniles)

 Yellowfin tuna (spawning, adults)

 Bigeye thresher shark (all)

 Bluefin tuna (eggs, larvae,  

spawning)

 Longbill spearfish (juveniles, adults)

 Longfin mako shark (all)

 Oceanic whitetip shark (all)

 Swordfish (larvae, juveniles, adults)

 Whale shark (all)

The central and western Gulf of Mexico may be important spawning habitat for Atlantic bluefin

tuna, and NMFS (2009) has designated a Habitat Area of Particular Concern (HAPC) for this

species.    The HAPC covers much of the deepwater Gulf of Mexico, including the lease area

(Figure 3).    The areal extent of the HAPC is approximately 15,000 mi2 (300,000 km2

).    The

prevailing assumption is that Atlantic bluefin tuna follow an annual cycle of foraging in

June through March off the eastern U.S. and Canadian coasts, followed by migration to the

Gulf of Mexico to spawn in April, May, and June (NMFS, 2009).  

On 27 May 2011, after an extensive scientific review, NOAA announced that Atlantic bluefin

tuna currently do not warrant species protection under the ESA.    However, NOAA classified

bluefin tuna as a species of concern, effectively placing it on a watch list as the agency awaits

new data on the impact of a stricter international management regimen.

A new amendment to the original EFH Generic Amendment was finalized in 2005 (GMFMC,

2005).  One of the most significant proposed changes in this amendment reduced the extent of

EFH relative to the 1998 Generic Amendment by removing the EFH description and

identification from waters between 100 fathoms and the seaward limit of the Exclusive

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Economic Zone (EEZ).  The Highly Migratory Species Fisheries Management Plan was amended

in 2009 to update EFH and HAPC to include the bluefin tuna spawning area (NMFS, 2009).

There are current NTLs (2009‐G39 and 2009‐G40) that provide guidance and clarification of the

regulations with respect to biologically sensitive underwater features and areas and benthic

communities that are considered EFH (MMS, 2009a,b).    A new EFH consultation has been

initiated between BOEM’s Gulf of Mexico Region and NOAA’s Southeastern Region.  Some EFH

requirements may change with the new agreement.  Until the new agreement is in place, the

1999 Programmatic Consultation with the elements described above will be followed

(BOEM, 2011, 2012).

Other HAPCs have been identified in the Gulf of Mexico by the GMFMC (2005).  These include

the Florida Middle Grounds, Madison‐Swanson Marine Reserve, Tortugas North and South

Ecological Reserves, Pulley Ridge, and several individual reefs and banks of the northwestern

Gulf of Mexico (Figure 3).    The nearest of these is Rezak‐Sidner Bank, located approximately

20 miles (33 km) from the lease area.  

Routine IPFs potentially affecting EFH include drilling rig presence, noise, and lights; effluent

discharges; water intakes; and two types of accidents: a small fuel spill and a large oil spill

(WCD).

Impacts of Drilling Rig Presence, Noise, and Lights

The drilling rig, as a floating structure in the deepwater environment, will act as an FAD.    In

oceanic waters, the FAD effect would be most pronounced for epipelagic fishes such as tunas,

dolphin, billfishes, and jacks, which are commonly attracted to fixed and drifting surface

structures (Holland et al., 1990; Higashi, 1994; Relini et al., 1994; MMS 2000, 2007b, 2008).  This

FAD effect would possibly enhance feeding of epipelagic predators by attracting and

concentrating smaller fish species.  Because the drilling rig is a single, temporary structure, any

impacts on EFH for highly migratory pelagic fishes are considered minor.

Impacts of Effluent Discharges

Other effluent discharges affecting EFH by diminishing ambient water quality include drilling

muds and cuttings, treated sanitary and domestic wastes, deck drainage, and miscellaneous

discharges such as desalination unit brine and uncontaminated cooling water, fire water, and

ballast water.  Impacts on water quality have been discussed previously.  No significant impacts

on EFH for highly migratory pelagic fishes are expected from these discharges.

Impacts of Water Intakes

As noted previously, cooling water intake will cause entrainment and impingement of plankton,

including fish eggs and larvae (ichthyoplankton).  Due to the limited scope and short duration of

drilling activities, any short‐term impacts on EFH for highly migratory pelagic fishes are not

expected to be biologically significant.

Impacts of a Small Fuel Spill

The probability of a fuel spill will be minimized by Hess’s preventative measures during routine

operations including fuel transfer.    In the unlikely event of a spill, implementation of Hess’s

OSRP will help diminish the potential for impacts on EFH.  SEP Appendix I provides detail on spill

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response measures.  Given the open ocean location of the lease area, the duration of a small

spill and opportunity for impacts to occur would be very brief.

Potential spill impacts on EFH are discussed in recent EISs (MMS, 2007b, 2008).  For this SEP,

there are no unique site‐specific issues with respect to spill impacts.

A small fuel spill in offshore waters would produce a slick on the water surface and increase the

concentrations of petroleum hydrocarbons and their degradation products.    The extent and

persistence of impacts would depend on the meteorological and oceanographic conditions at

the time and the effectiveness of spill response measures.  Section A.9.2 discusses the likely fate

of a small fuel spill and indicates that over 90% would be evaporated or dispersed naturally

within 24 hours.  The area of the sea surface with diesel fuel on it would range from 0.5 to 5 ha

(1.2 to 12 ac), depending on sea state and weather conditions.

A small fuel spill could have localized impacts on EFH for highly migratory pelagic fishes,

including tunas, swordfishes, billfishes, and sharks.    These species occur as transients in the

lease area.    A spill would also produce short‐term impact on water quality in the HAPC for

spawning Atlantic bluefin tuna, which covers much of the deepwater Gulf of Mexico.  The areal

extent of the affected area would represent a negligible portion of the HAPC.

A small fuel spill would not affect EFH for corals and coral reefs, the nearest EFH being the

topographic features located approximately 17 miles (27 km) from the lease area along the shelf

edge south of Louisiana.    A small fuel spill would float and dissipate on the sea surface and

would not contact these features.

Impacts of a Large Oil Spill (WCD)

Potential spill impacts on EFH are discussed in recent EISs (MMS, 2007b, 2008).  For this SEP,

there are no unique site‐specific issues with respect to EFH.

An oil spill in offshore waters would temporarily increase hydrocarbon concentrations on the

water surface and potentially in the subsurface as well.  Given the extent of EFH designations in

the Gulf of Mexico (GMFMC, 2005; NMFS, 2009), some impact on EFH would be unavoidable.

A large spill could affect the EFH for many managed species including shrimps, stone crab, spiny

lobster, reef fishes, coastal migratory pelagic fishes, and red drum.  It would result in adverse

impacts on water quality and water column biota including phytoplankton, zooplankton, and

nekton.    In coastal waters, sediments could be contaminated and result in persistent

degradation of the seafloor habitat for managed demersal fish and shellfish species.

The lease area is within the HAPC for spawning Atlantic bluefin tuna (NMFS, 2009).  A large spill

could temporarily degrade the HAPC due to increased hydrocarbon concentrations in the water

column, with the potential for lethal or sublethal impacts on spawning tuna.  Potential impacts

would depend in part on the timing of a spill, as this species migrates to the Gulf of Mexico to

spawn in April, May, and June (NMFS, 2009).

Topographic features located in GB 121, 17 miles (27 km) north of the lease area, are designated

as EFH under the corals and coral reefs management plan.  An accidental spill would be unlikely

to affect this area, since a surface slick would not reach these features due to their depth.

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C.6 Archaeological Resources

C.6.1 Shipwreck Sites

BOEM (2011, 2012) has reexamined the analyses for archaeological resources presented in

MMS (2007b, 2008), based on additional information available since the publication of these

two documents and in consideration of the Macondo oil spill event.    Substantial new

information that alters the impact conclusion for archaeological resources presented in

MMS (2007b, 2008) has come to light as a result of BOEM‐sponsored studies and industry

surveys.    Specifically, evidence of damage to significant cultural resources (i.e., historic

shipwrecks) has been shown to have occurred because of an incomplete knowledge of seafloor

conditions in lease areas >200 m (656 ft) deep that have been exempted from high‐resolution

surveys.    Since significant historic shipwrecks have recently been discovered outside the

previously designated high‐probability areas (some of which show evidence of impacts from

permitted activities prior to their discovery), a survey is now required for exploration and

development projects (BOEM, 2011, 2012).

The lease area is not on the list of leases with a high potential for historic shipwrecks.  There

were no indications of wrecks or other archaeological resources detected near the proposed

wellsites during the shallow hazards assessment (GEMS, 2011).  Hess will abide by the applicable

requirements of NTL 2005‐G07, which stipulate that work be stopped at the project site should

any previously undetected archaeological resource be discovered after work has begun until

appropriate surveys and evaluations have been completed.

Because there are no known or indicated shipwreck sites in the lease area, there are no routine

IPFs that are likely to affect shipwrecks.    Impacts of a large oil spill (WCD) are the only IPFs

considered.    A small fuel spill would not affect shipwrecks because the oil would float and

dissipate on the sea surface.

Impacts of a Large Oil Spill (WCD)

The MMS (2007b) estimated that a severe subsurface blowout could resuspend and disperse

sediments within a 300‐m (984‐ft) radius.  Because there are no historic shipwrecks in the lease

area, this impact would not be relevant.

Previous analyses (MMS, 2007a, 2008) concluded that oil spills would be unlikely to affect

archaeological sites beyond the immediate vicinity of the wellhead (i.e., due to physical impacts

of a blowout) because the oil would rise quickly to the sea surface directly over the spill location.  

However, during the Macondo spill, subsurface plumes were reported at a water depth of about

1,100 m (3,600 ft), extending at least 22 miles (35 km) from the wellsite and persisting for more

than a month (Camilli et al., 2010).  The subsurface plumes apparently resulted from the use of

dispersants at the wellhead (Joint Analysis Group, 2010c).  While the behavior and impacts of

subsurface plumes are not well known, a subsurface plume could have the potential to contact

shipwreck sites beyond the 300‐m (984‐ft) radius estimated by MMS (2007a, 2008), depending

on its extent, trajectory, and persistence.  If oil from a subsea spill should come into contact with

wooden shipwrecks on the seafloor, it could adversely affect their condition or preservation.  

Should there be any indication that potential shipwreck sites could be affected, in accordance

with NTL 2005‐G07 Hess will immediately halt operations, take steps to ensure that the site is

not disturbed in any way, and contact the Regional Supervisor, Leasing and Environment, within

48 hours of its discovery.   Hess would cease all operations within 305 m (1,000 ft) of the site

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until the Regional Supervisor provides instructions on steps to take to assess the site’s potential

historic significance and protect it.

A spill entering shallow coastal waters could conceivably contaminate an undiscovered

shipwreck site.  As noted by MMS (2007b), should an oil spill contact a coastal historic site, such

as a fort or a lighthouse, the major impact would be a temporary, reversible visual impact from

oil contact and contamination of the site and its environment.

C.6.2 Prehistoric Archaeological Sites

Available evidence suggests that sea level in the northern Gulf of Mexico was at least 90 m

(295 ft), and possibly as much as 130 m (427 ft), lower than present sea level during the period

20,000 to 17,000 years Before Present (B.P.) (Nelson and Bray, 1970).  Sea level in the northern

Gulf reached its present stand around 3,500 years B.P. (Pearson et al., 1986).

During periods that the continental shelf was exposed above sea level, the area was open to

habitation by prehistoric peoples.    The advent of early man into the Gulf of Mexico region is

currently accepted to be around 12,000 years B.P. (Aten, 1983).    The sea‐level curve for the

northern Gulf of Mexico proposed by Coastal Environments, Inc. (CEI) suggests that sea level at

12,000 years B.P. would have been approximately 45 to 60 m (148 to 197 ft) below the

present‐day sea level (CEI, 1977, 1982).  On this basis, the continental shelf shoreward of the

45‐ to 60‐m (148‐ to 197‐ft) bathymetric contours has potential for prehistoric sites dating after

12,000 years B.P.  Because of inherent uncertainties in both the depth of sea level and the entry

date of prehistoric man into North America, the MMS adopted the 60‐m (197‐ft) water depth as

the seaward extent for archaeological site potential in Gulf of Mexico region.

With water depth of approximately 2,623 ft (800 m), the wellsites are well beyond the 60‐m

(197‐ft) depth contour used by the BOEM as the seaward extent for prehistoric archaeological

site potential in the Gulf of Mexico.  Because prehistoric archaeological sites are not found in

the lease area, the only relevant IPF is a large oil spill (WCD).  A small fuel spill would not affect

prehistoric archaeological resources because the oil would float and dissipate on the sea

surface.

Impacts of a Large Oil Spill (WCD)

Because prehistoric archaeological sites are not found in the lease area, they would not be

affected by the physical effects of a subsea blowout.  The MMS (2007b) estimates that a severe

subsurface blowout could resuspend and disperse sediments within a 300‐m (984‐ft) radius.

Along the northern Gulf Coast, prehistoric sites occur frequently along the barrier islands and

mainland coast and along the margins of bays and bayous (MMS, 2007b).  If a spill did reach a

prehistoric site along these shorelines it could coat fragile artifacts or site features and

compromise the potential for radiocarbon dating organic materials in a site (although other

dating methods are available and it is possible to decontaminate an oiled sample for

radiocarbon dating).  Coastal prehistoric sites could also be damaged by spill cleanup operations

(e.g., by destroying fragile artifacts and disturbing the provenance of artifacts and site features).

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C.7 Coastal Habitats and Protected Areas

Coastal habitats in the northeastern Gulf of Mexico that may be affected by oil and gas activities

are described in recent EISs (MMS, 2007b, 2008) and in a literature review by Collard and Way

(1997).    Coastal habitats inshore of the project area include barrier beaches and dunes,

wetlands, and submerged seagrass beds.  Generally, most of the northeastern Gulf is fringed by

barrier beaches, with wetlands and/or submerged seagrass beds occurring in sheltered areas

behind the barrier islands and in estuaries.

Due to the distance from shore, there are no IPFs associated with routine activities at the

project site that are likely to affect beaches and dunes, wetlands, seagrass beds, coastal wildlife

refuges, wilderness areas, or any other managed or protected coastal area.  The support bases

at Port Fourchon and Galliano are not in wildlife refuges or wilderness areas.  Potential impacts

of support vessel traffic are addressed briefly below.

A small fuel spill in the lease area would be unlikely to affect coastal habitats, as the lease area is

130 miles (209 km) from the nearest shoreline.  As explained in Section A.9.2, a small fuel spill

would break up before reaching shore.

Impacts of Support Vessel Traffic

For OCS activities in general, support operations, including crew boats and supply boats, may

have a minor incremental impact on coastal habitats.  Over time, with a large number of vessel

trips, vessel wakes can erode shorelines along inlets, channels, and harbors.    Support

operations, including crew boats and supply boats as detailed in SEP Appendix O, may have a

minor incremental impact on coastal habitats or protected areas.  Impacts will be minimized by

following the speed and wake restrictions in harbors and channels.

Impacts of a Large Oil Spill (WCD)

Potential spill impacts on coastal habitats are discussed in recent EISs (MMS, 2007b, 2008).  

Coastal habitats inshore of the project area include barrier beaches and dunes, wetlands, and

submerged seagrass beds.  For this SEP, there are no unique site‐specific issues with respect to

coastal habitats.

The shorelines within the geographic range predicted by the OSRA modeling (Table 3) include

extensive barrier beaches and wetlands, with submerged seagrass beds occurring in sheltered

areas behind the barrier islands and in estuaries.  NWRs and other protected areas along the

coast are discussed in a recent lease sale EIS (MMS, 2007b) and Hess’s OSRP.    Coastal and

near‐coastal wildlife refuges, wilderness areas, and State and National parks within the

geographic range of potential shoreline contacts after 120 days are listed in Table 7.

Table 7. Wildlife refuges, wilderness areas, and State and National parks within the geographic

range of the potential shoreline contacts after 120 days.

County or Parish, State Wildlife Refuge, Wilderness Area,

or State/National Park

Lower Rio Grande Valley National Wildlife Refuge

Laguna Atascosa National Wildlife Refuge

Padre Island National Seashore

Isla Blanca Park

Andy Bowie County Park  

Cameron County, Texas

Laguna Madre Estuarine and Coastal Marine Area

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County or Parish, State Wildlife Refuge, Wilderness Area,

or State/National Park

Lower Rio Grande Valley National Wildlife Reserve

Laguna Atascosa National Wildlife Reserve  

Padre Island National Seashore Willacy County, Texas

Laguna Madre Estuarine And Coastal Marine Area

Padre Island National Seashore Kenedy County, Texas

Laguna Madre Estuarine and Coastal Marine Area

Padre Island National Seashore Kleberg County, Texas

Laguna Madre Estuarine and Coastal Marine Area

Laguna Madre Estuarine and Coastal Marine Area

Mustang Island State Park

Lake Corpus Christi State Park

Port Aransas Park

Nueces County, Texas

Mission‐Aransas National Estuarine Research Reserve

Mission‐Aransas National Estuarine Research Reserve

Aransas County, Texas   Aransas National Wildlife Refuge

Goose Island State Park

Mission‐Aransas National Estuarine Research Reserve

Aransas National Wildlife Refuge

Matagorda Island State Park

Guadalupe Delta Wildlife Management Area

Calhoun County, Texas

Welder Flats Coastal Preserve

Big Boggy National Wildlife Refuge

Aransas National Wildlife Refuge

Mad Island Wildlife Management Area Matagorda County, Texas  

San Bernard National Wildlife Refuge

San Bernard National Wildlife Refuge

Peach Point Wildlife Management Area

Brazoria National Wildlife Refuge Brazoria County, Texas

Christmas Bay Coastal Preserve and Christmas Bay State Park  

Galveston Island State Park

Brazoria National Wildlife Refuge

Apffel Park

Seawolf Park

Old Fort Travis Park

Atkinson Island Wildlife Management Area

Ft. Anahuc Park

Anahuac National Wildlife Refuge

Galveston County, Texas

McFaddin National Wildlife Refuge

McFaddin National Wildlife Refuge

Sea Rim State Park

Murphree Wildlife Management Area

Jefferson County, Texas  

Texas Point National Wildlife Refuge

Sabine National Wildlife Refuge

Cameron Prairie National Wildlife Refuge

Lacassine National Wildlife Refuge

Little Pecan Island Natural Area

Peveto Woods Natural Area

Lower Neches Wildlife Management Area

Cameron Parish, Louisiana  

Rockefeller Wildlife Management Area

Louisiana Rockefeller Wildlife Management Area Vermilion Parish, Louisiana Paul J. Rainey Wildlife Management Area

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County or Parish, State Wildlife Refuge, Wilderness Area,

or State/National Park

Atchafalaya Delta Wildlife Management Area

Mandalay National Wildlife Refuge

Isles Dernieres Barrier Islands Refuge Terrebonne Parish, Louisiana

Pointe Au Chein Wildlife Management Area

Louisiana Pointe Au Chein Wildlife Management Area Lafourche Parish Louisiana

Wisner Wildlife Management Area

Salvador Wildlife Management Area

Jean Lafitte National Historical Park and Preserve

Delta National Wildlife Refuge

Pass‐a‐Loutre Wildlife Management Area

Breton National Wildlife Refuge

Plaquemines Parish, Louisiana  

St. Bernard State Park

The level of impacts from oil spills on coastal habitats depends on many factors, including the oil

characteristics, the geographic location of the landfall, and the weather and oceanographic

conditions at the time (MMS, 2007b).    Oil that makes it to beaches may be either liquid

weathered oil, an oil‐and‐water mousse, or tarballs (MMS, 2007b).  Oil is generally deposited on

beaches in lines defined by wave action at the time of landfall.  Oil that remains on the beach

will thicken as its volatile components are lost.  Thickened oil may form tarballs or aggregations

that incorporate sand, shell, and other materials into its mass.    Tar may be buried to varying

depths under the sand.  On warm days, both exposed and buried tarballs may liquefy and ooze.  

Oozing may also serve to expand the size of a mass as it incorporates beach materials.  Oil on

beaches may be cleaned up manually, mechanically, or both.  Some oil can remain on the beach

at varying depths and may persist for several years as it slowly biodegrades and volatilizes.

Wetlands are highly sensitive to oiling.  The MMS (2007b) predicted that for every 50 bbl of oil

contacting wetlands, approximately 2.7 ha (6.7 ac) of wetland vegetation will experience

dieback.  Thirty percent of these damaged wetlands are assumed to recover within 4 years, and

85% within 10 years.    About 15% of the contacted wetlands are expected to be converted

permanently to open‐water habitat.  The critical concentration of oil is that concentration above

which impacts to wetlands will be long‐term and recovery will take longer than two growing

seasons, and that causes plant mortality and some permanent wetland loss.    Critical

concentrations of various oils are expected to vary broadly for wetland types and wetland plant

species.  Louisiana wetlands are assumed to be more sensitive to oil contact than elsewhere in

the Gulf because of high cumulative stress (MMS, 2007b).  In addition to the direct impacts of

oil, cleanup activities in marshes may accelerate rates of erosion and retard recovery rates,

which have been reported to require from years to decades following a spill (MMS, 2007b;

BOEM, 2011, 2012).

C.8 Socioeconomic and Other Resources

C.8.1 Recreational and Commercial Fishing

BOEM has reexamined the analysis for recreational and commercial fishing presented in

MMS (2007b, 2008) based on additional information and in consideration of the Macondo oil

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spill event.  However, no additional information obtained after the previous EISs was found that

would alter the potential impacts on commercial and recreational fishing discussed in those EISs

(BOEM, 2011, 2012).

The main commercial fishing activity in deep waters of the northern Gulf of Mexico is pelagic

longlining for tunas, swordfishes, and other billfishes (Continental Shelf Associates, Inc., 2002).  

Pelagic longlining has occurred historically in the project area, primarily during spring and

summer.  In August 2000, the Federal government closed two areas in the northeastern Gulf of

Mexico to longline fishing (65 FR 47214, 1 August 2000).    The lease is outside of the closure

areas.

Longline gear consists of monofilament line deployed from a moving vessel and generally

allowed to drift for 4 to 5 hours (Continental Shelf Associates, Inc., 2002).  As the mainline is put

out, baited leaders and buoys are clipped in place at regular intervals.  It takes 8 to 10 hours to

deploy a longline and about the same time to retrieve it.    Longlines are often set near

oceanographic features such as fronts or downwellings, with the aid of sophisticated on‐board

temperature sensors, depth finders, and positioning equipment.  Vessels typically are 10 to 30 m

(33 to 98 ft) long, and their trips last from about 1 to 3 weeks.    The main Gulf of Mexico

homeports for longlining vessels are in Louisiana (Dulac and Venice) and Florida

(Destin, Madeira Beach, and Panama City).

It is unlikely that any commercial fishing activity other than longlining occurs at or near the

project area.   Benthic species targeted by commercial fishers occur on the upper continental

slope, well inshore of the project area.    Royal red shrimp (Pleoticus robustus) are caught by

trawlers in water depths of about 250 to 550 m (820 to 1,804 ft).  Tilefish (primarily Lophalotilus

chamaeleonticeps) are caught by bottom longlining in water depths from about 165 to 450 m

(540 to 1,476 ft) (Continental Shelf Associates, Inc., 2002).

Most recreational fishing activity in the region occurs in water depths less than 200 m (656 ft)

(Continental Shelf Associates, Inc., 1997, 2002).    In deeper water, the main attraction to

recreational fishers would be petroleum rigs offshore Texas and Louisiana.  Due to the distance

from shore, it is unlikely that recreational fishing activity is occurring in the lease area.

The only routine IPF potentially affecting fisheries is drilling rig presence (including noise and

lights).  Two potential accidents are also addressed below: a small fuel spill and a large oil spill

(WCD).

Impacts of Drilling Rig Presence

There is a slight possibility of pelagic longlines becoming entangled in the drilling rig.    For

example, in January 1999 a portion of a pelagic longline snagged on the acoustic Doppler

current profiler of a drillship working in the Gulf of Mexico (Continental Shelf Associates, Inc.,

2002).    The line was removed without incident.   Generally, longline fishers use radar and are

aware of offshore structures and ships when placing their sets.  Therefore, little or no impact on

pelagic longlining is expected.

Because it is unlikely that any recreational fishing activity is occurring in the project area, no

adverse impacts are anticipated.   Other factors such as effluent discharges are likely to have

negligible impacts on commercial or recreational fisheries due to rapid dispersion, the small

area of ocean affected, and the intermittent nature of the discharges.

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Impacts of a Small Fuel Spill

The probability of a fuel spill will be minimized by Hess’s preventative measures during routine

operations including fuel transfer.    In the unlikely event of a spill, implementation of Hess’s

OSRP will potentially mitigate and reduce the potential for impacts.    SEP Appendix I provides

detail on spill response measures.  Given the open ocean location of the lease area, the duration

of a small spill and opportunity for impacts to occur would be very brief.

Pelagic longlining activities in the lease area, if any, could be interrupted in the event of a small

fuel spill.    The area of the sea surface with diesel fuel on it would range from 0.5 to 5 ha

(1.2 to 12 ac), depending on sea state and weather conditions.    Fishing activities could be

interrupted due to the activities of response vessels operating in the lease area.   A small fuel

spill would not affect coastal water quality because the spill would not be expected to make

landfall or reach coastal waters prior to breaking up (see Section A.9.2).

Impacts of a Large Oil Spill (WCD)

Potential spill impacts on fishing activities are discussed in recent EISs (MMS, 2007b, 2008).  For

this SEP, there are no unique site‐specific issues with respect to this activity.

Pelagic longlining activities in the lease area and other fishing activities in the northern Gulf of

Mexico could be interrupted in the event of a large oil spill.  A spill may or may not result in

fishery closures, depending on the duration of the spill, the oceanographic and meteorological

conditions at the time, and the effectiveness of spill response measures.  The recent Macondo

spill provides information about the maximum potential extent of fishery closures in the event

of a large oil spill in the Gulf of Mexico (NMFS, 2010d).   At its peak on 12 July 2010, closures

encompassed 84,101 mi2 (217,821 km2

), or 34.8% of the U.S. EEZ in the Gulf of Mexico.

C.8.2 Public Health and Safety

There are no IPFs associated with routine operations that are expected to affect public health

and safety.  Impacts of a small fuel spill and a large oil spill (WCD) are addressed below.

Impacts of a Small Fuel Spill

The probability of a fuel spill will be minimized by Hess’s preventative measures during routine

operations including fuel transfer.    In the unlikely event of a spill, implementation of Hess’s

OSRP will potentially alleviate the potential for impacts.  SEP Appendix I provides detail on spill

response measures.

A small fuel spill would not have any impacts on public health and safety because it would affect

only a small area of the open ocean 130 miles (209 km) from the nearest shoreline and nearly all

of the diesel fuel would evaporate or disperse naturally within 24 hours.  Response crews would

be equipped with appropriate safety equipment to avoid injury and health effects.  A small fuel

spill would not be expected to make landfall or reach coastal waters prior to breaking up

(see Section A.9.2).

Impacts of a Large Oil Spill (WCD)

In the event of a large spill from a blowout, the main safety and health concerns are those of the

offshore personnel involved in the incident and those responding to the spill.   The drilling rig

maintains a Shipboard Oil Pollution Emergency Plan as required under MARPOL 73/78.

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Depending on the spill rate and duration, the physical/chemical characteristics of the oil,

meteorological and oceanographic conditions at the time, and the effectiveness of spill response

measures, the public could be exposed to oil on the water and along the shoreline, including

skin contact or breathing VOCs.    Crude oil is a highly flammable material, and any smoke or

vapors from a crude oil fire can cause irritation, and in large quantities may pose a health

hazard.

Data from the recent Macondo spill provide relevant information about the types of health

issues that may occur in the event of a large oil spill (Centers for Disease Control and Prevention,

2010a).  Wildlife cleaning and rehabilitation workers have reported concerns including scrapes

and cuts, itchy or red skin or rash, and symptoms of headache or feeling faint, dizzy, or fatigued.  

Hand, shoulder, or back pain was also reported by some wildlife‐cleaning workers.  Personnel

working on offshore vessels or providing direct oversight to offshore vessels, including

USCG personnel, civilian contractors, and other responders who were exposed to oil and

dispersants, had a 7 to 12 times higher prevalence of upper respiratory symptoms and cough

than those not exposed (Centers for Disease Control and Prevention, 2010b).  Another potential

occupational hazard for spill response workers in general was heat stress from work in a hot and

humid environment.    Initial symptoms from cleanup workers who sought medical care in

Louisiana were typical of acute exposure to hydrocarbons or H2S, e.g., headaches, dizziness,

nausea, vomiting, cough, respiratory distress, and chest pain (Solomon and Janssen, 2010).

C.8.3 Employment and Infrastructure

There are no IPFs associated with routine operations that are expected to affect employment

and infrastructure.  The project involves drilling with support from existing shorebase facilities in

Louisiana.    No new or expanded facilities will be constructed, and no new employees are

expected to move permanently into the area.    The project will have a negligible impact on

socioeconomic conditions such as local employment, existing offshore and coastal infrastructure

(including major sources of supplies, services, energy, and water), and minority and lower

income groups.  Impacts of a small fuel spill and a large oil spill (WCD) are addressed below.

Impacts of a Small Fuel Spill

The probability of a fuel spill will be minimized by Hess’s preventative measures during routine

operations including fuel transfer.    In the unlikely event of a spill, implementation of Hess’s

OSRP will potentially mitigate and reduce the potential for impacts.    SEP Appendix I provides

detail on spill response measures.  Given the open ocean location of the lease area, the duration

of a small spill and opportunity for impacts to occur would be very brief.

A small fuel spill that is dissipated within a few days would have little or no economic impact, as

the spill response would use existing facilities, resources, and personnel.

Impacts of a Large Oil Spill (WCD)

Potential socioeconomic impacts of an oil spill are discussed in recent EISs (MMS, 2007b, 2008).  

For this SEP, there are no unique site‐specific issues with respect to employment and coastal

infrastructure.    A large spill could cause economic impacts in several ways: it could result in

extensive fishery closures that put fishermen out of work; it could result in temporary

employment as part of the response effort; it could result in adverse publicity that affects

employment in coastal recreation and tourism industries; and it could result in another

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suspension of OCS drilling activities, including service and support operations that are an

important part of local economies.

In addition to the analyses presented by MMS (2007b, 2008) and BOEM (2011, 2012), a recent

study explored the economic impacts of the Macondo spill on oil and gas industry employment

due to suspension of deepwater drilling (Inter‐Agency Economic Report, 2010).    The study

indicates that during the moratorium, the number of oil industry workers in the Gulf of Mexico

fell by about 2,000 and may have indirectly caused a temporary loss of 8,000 to 12,000 jobs

along the Gulf Coast.    Total spending by drilling operators is estimated to have declined by

$1.8 billion over a six‐month period; this direct reduction in spending affected employment in

the industries that supply the Gulf drilling industry and in all other industries affected by

declines in consumer and business spending (Inter‐Agency Economic Report, 2010).

C.8.4 Recreation and Tourism

BOEM has reexamined the analyses for recreation and tourism presented in MMS (2007b, 2008)

based on additional information and in consideration of the Macondo oil spill event.  No new

information was found that would alter the potential impacts on recreation and tourism (BOEM,

2011, 2012).

There are no known recreational uses of the lease area.  Recreational resources and tourism in

coastal areas would not be affected by any routine activities due to the distance from shore.  

Compliance with NTL 2012‐BSEE‐G01 will minimize the chance of trash or debris being lost

overboard from the drilling rig and subsequently washing up on beaches.

Impacts of a Small Fuel Spill

The probability of a fuel spill will be minimized by Hess’s preventative measures during routine

operations including fuel transfer.    In the unlikely event of a spill, implementation of Hess’s

OSRP will potentially help mitigate and reduce the potential for impacts.    SEP Appendix I

provides detail on spill response measures.  Given the open ocean location of the lease area, the

duration of a small spill and opportunity for impacts to occur would be very brief.

A small fuel spill in the lease area would be unlikely to affect recreation and tourism.  There are

no known recreational or tourism activities occurring in the lease area, and as explained in

Section A.9.2, a small fuel spill would not be expected to make landfall or reach coastal waters

prior to breaking up.

Impacts of a Large Oil Spill (WCD)

Potential impacts of an oil spill on recreation and tourism are discussed in recent EISs

(MMS, 2007b, 2008; BOEM, 2011, 2012).  For this SEP, there are no unique site‐specific issues

with respect to these impacts.

Impacts on recreation and tourism would vary depending on the duration of the spill and its

fate, including the effectiveness of response measures.  A large spill that reached coastal waters

and shorelines could adversely affect recreation and tourism by contaminating beaches and

wetlands, resulting in negative publicity that encourages people to stay away.

In addition to the analysis presented by MMS (2007b, 2008), recent and ongoing studies have

explored the economic impacts of the Macondo spill, including tourism and “brand” damage

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(IEM, 2010; Oxford Economics, 2010).  The U.S. Travel Association has estimated the economic

impact of the Macondo spill on tourism across the Gulf Coast over a 3‐year period at

$22.7 billion (Oxford Economics, 2010).

C.8.5 Land Use

Land use along the northern Gulf Coast is discussed in recent lease sale EISs (MMS, 2007b,

2008).    There are no routine IPFs potentially affecting land use.    The project will use existing

onshore support facilities in Louisiana.  The land use at the existing shorebase sites is industrial.  

The project will not involve any new construction or changes to existing land use and therefore

will not have any impacts.  Levels of boat and helicopter traffic, as well as demand for goods and

services including scarce coastal resources, will represent a small fraction of the level of activity

occurring at the shorebases.

A large oil spill (WCD) is the only relevant IPF.  A small fuel spill would not have any impacts on

land use, as the response would be staged out of existing shorebases and facilities.

Impacts of a Large Oil Spill (WCD)

The initial response for a large oil spill would be staged out of existing facilities, with no effect on

land use.    A large spill could have limited temporary impacts on land use along the coast if

additional staging areas were needed.    For example, during the Macondo spill, temporary

staging areas were established in Louisiana, Mississippi, Alabama, and Florida for spill response

and cleanup efforts.    In the event of a large spill in the lease area, similar temporary staging

areas could be established (see SEP Appendix I).  These areas would eventually return to their

original use as the response is demobilized.

C.8.6 Other Marine Uses

The lease area is not located within any USCG‐designated fairway or shipping lane or Military

Warning Area.  Hess will coordinate with the Air Armament Center to control electromagnetic

emissions during operations and will comply with all BOEM requirements and lease stipulations

to avoid impacts on uses of the area by military vessels and aircraft.

The proposed wellsites are within 2,048 to 9,953 ft (624 to 3,034 m) of existing infrastructure in

the Llano field.  There are no other known marine uses of the lease area.

There are no IPFs from routine project activities that are likely to affect other marine uses of the

lease area.  A large oil spill (WCD) is the only relevant accident IPF.  A small fuel spill would not

have any impacts on other marine uses, as spill response activities would be mainly within the

lease area and the duration would be brief.

Impacts of a Large Oil Spill (WCD)

An accidental spill would be unlikely to significantly affect shipping or other marine uses.  The

block is not located within any USCG‐designated fairway or shipping lane or Military Warning

Area.  In the event of a large spill requiring numerous response vessels, coordination would be

required to manage the vessel traffic for safe operations.    Hess will comply with BOEM

requirements and lease stipulations to avoid impacts on uses of the area by military vessels and

aircraft.

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In the event of a large spill requiring numerous vessels in the area, coordination would be

required to ensure that no anchoring or seafloor‐disturbing activities occur near existing

pipelines and flowlines.

D.  Environmental Hazards

D.1 Geologic Hazards

The regional geohazards report (GEMS, 2011) concluded that the wellsites are free of any

significant geological hazards and are suitable for the proposed activities.  See SEP Appendix C

for supporting geological and geophysical information.

D.2 Severe Weather

Under most circumstances, weather is not expected to have any effect on the proposed

activities.    Extreme weather, including high winds, strong currents, and large waves, was

considered in the design criteria for the drilling rig under consideration for this project.   High

winds and limited visibility during a severe storm could disrupt support activities (vessel and

helicopter traffic) and make it necessary to suspend some activities on the drilling rig for safety

reasons until the storm or weather event passes.    In the event of a hurricane, procedures as

outlined in the rig‐specific Emergency Evacuation Plan would be adhered to.

D.3 Currents and Waves

Metocean conditions such as sea states, wind speed, ocean currents, etc. will be continuously

monitored.  Under most circumstances, physical oceanographic conditions are not expected to

have any effect on the proposed activities.  Strong currents (e.g., caused by Loop Current eddies

and intrusions) and large waves were considered in the design criteria for the drilling rig under

consideration for this project.  High waves during a severe storm could disrupt support activities

(i.e., vessel and helicopter traffic) and make it necessary to suspend some activities on the

drilling rig for safety reasons until the storm or weather event passes.

E.  Alternatives

No formal alternatives were evaluated in this EIA for an SEP.  However, various technical and

operational options, including the location of the wellsites and the selection of a drilling unit,

were considered by Hess in developing the proposed action.

F.  Mitigation Measures

The proposed action includes numerous mitigation measures required by laws, regulations, and

BOEM lease stipulations and NTLs.    The project will comply with all applicable Federal, State,

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and local requirements concerning air pollutant emissions, discharges to water, and solid waste

disposal.  All project activities will be conducted under guidance by Hess’s OSRP and will include

the measures described in SEP Appendix I.

G.  Consultation

No persons or agencies were consulted during the preparation of this EIA.

H.  Preparers

The EIA was prepared by CSA International, Inc.  Contributors included:

 Cindy Chandool, Ph.D. (Senior Scientist);

 Carlyle Kalloo (Senior Scientist);

 M. John Thompson (Senior Scientist);

 Neal Phillips, Ph.D. (Senior Scientist);

 Keith VanGraafeiland (GIS/Remote Sensing Specialist);

 Kristen L. Metzger (Library and Information Services Director); and

 Danielle Johnson (Technical Editor).

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FOR PUBLIC RELEASE
Hess Corporation    Llano Field  

Supplemental EP    Garden Banks Block 386, OCS‐G10350

Appendix T

Administrative Information  

(a) Exempted Information Description

In accordance with BOEM/BSEE NTL No. 2008‐G04, the geologic objectives, BHL, TVD, and MD

information on form BOEM‐0137; descriptions of any new or unusual technology; production

rates and life of reservoirs; all items under Geological and Geophysical Information except for

the non‐proprietary versions of the shallow hazards assessments; correlative well information

used to justify H2S classification; and mineral resource conservation information have been

removed from the public information copies.

(b) Bibliography

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341, 342, 343, 384, 385, 386, 387, 428, 429, 430 and 431, Garden Banks Area, Project No. 2411‐

5009, prepared for Shell Exploration & Production, Inc.    

Hess Corporation Oil Spill Response Plan, initially approved March 15, 2010, last modification

submitted September 30, 2010, with 2‐year certification issued January 10, 2011.

C&C Technologies, Inc., 2003, Engineering and Hazard Study Report, Garden Banks Blocks 385

and 426, C&C Technologies, Inc., Project No. 3567‐3663, June 2003.

Fugro Geoservices, Inc., 1998a, Geohazards Assessment, Blocks 297, 298, 341, 342, 385, and

386, Garden Banks Area, Fugro Geoservices, Project No. 0201‐3669, August 20, 1998.

Fugro Geoservices, Inc., 1998b, Geotechnical Investigation, Blocks 385 and 386, Garden Banks

Area, Fugro Geoservices, Project No. 0201‐3636‐1, September, 1998.

Fugro Geoservices, Inc., 1999, Report on Blocks 345, 346, 389, and 390, Garden Banks Area,

Fugro Geoservices, Project No. 0201‐3755, March, 1999.

Fugro Geoservices, Inc., 2000, Shallow Hazards Report, OCS‐G 15880, Block 342, Garden Banks

Area, Fugro Geoservices, Inc., Project No. 2499‐2054, January 2000.

GEMS, 2002, Preliminary Pipeline Planning Study, Garden Banks Block 385, Geoscience Earth &

Marine Services, Inc., Project No. 1101‐458, February, 2002.

FOR PUBLIC RELEASE