UNITED STATES GOVERNMENT MEMORANDUM

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

Public Information copy of Exploration Plan
Control # - N-09821 Type - Initial Exploration Plan Lease(s) - OCS-G21817 Block - 768 Green Canyon Area OCS-G34557 Block - 724 Green Canyon Area Operator - Anadarko Petroleum Corporation Drill, Complete Wells GC 724 A, AA, AAA

Not Found

Attached is a copy of the subject plan for public comments on issues that should be addressed in an Environmental Assessment.

It has been deemed submitted as of this date and is under review for approval.

Tonya Jez Plan Coordinator Description -
Rig Type - Subject: From: September 12, 2014

# INITIAL EXPLORATION PLAN N-9821

ANADARKO PETROLEUM CORPORATION

GREEN CANYON BLOCK 724 OCS-G 34557

PUBLIC COPY

RECORD OF CHANGE LOG

Submission Type Date Sent to BOEM Summary of Submission Page Numbers Initial 07/09/2014 Submit Initiall EP All Amendment 07/30/2014 Add additional shorebase 6 Final version of EP 08/22/2014 Final copy of plan with all revisions included All

Record of Change Log 08/22/2014 Record of Change Log 1

# PUBLIC

INITIAL EXPLORATION PLAN

GREEN CANYON BLOCK 724 OCS-G 34557

OFFSHORE, LOUISIANA

Anadarko Petroleum Corporation 1201 Lake Robbins Drive The Woodlands, Texas 77380 Contact: Jill Fowler jill.fowler@anadarko.com (832) 636-1554

1 – Hard Copy Confidential 1 – CD Confidential 1 – Hard Copy Public Information 2 – CDs Public Information



### July, 2014

## INITIAL EXPLORATION PLAN LEASES OCS-G 34557 GREEN CANYON BLOCK 724

A. Plan Contents

B. General Information

C. Geological, Geophysical

D. Hydrogen Sulfide Information

E. Biological, Physical and Socioeconomic Information

F. Wastes and Discharge Information

G. Air Emissions Information

H. Oil Spill Information

I. Environmental Monitoring Information

J. Lease Stipulations

K. Support Vessels and Aircraft Information

L. Onshore Support Facilities Information

M. Coastal Zone Management Act Information

N. Environmental Impact Analysis

O. Administrative Information

## A PLAN CONTENTS

(a) Plan Information Form

Under this Initial Exploration Plan (EP), Anadarko Petroleum Corporation (Anadarko) proposes to drill and complete three wells total in Green Canyon (GC) Block 724.

The wells will be drilled using either a Dynamically Positioned (DP) Drillship or DP Semisubmersible drilling rig. Drilling and completion operations for th e proposed well locations will utilize a Subsea BOP stack. OCS Plan Information Fo rm BOEM-137 is enclosed as Attachment A-1.

(b) Location

Enclosed as Attachment A-2 is a well location plat at a scale of 1 inch = 2000 feet that depicts the surface location and water depth of the proposed well.

(c) Safety and Pollution Prevention Features

Safety features on the drilling unit will include we ll control, pollution prevention, safe welding procedures, and blowout prevention equipment as descri bed in Title 30 CFR Part 250, Subparts C, D, E, G and O; and as further clarified by BOEM Notices to Lessees, and applicable regulations of the Environmental Protection Agency and the U.S. Coast Guar d. The appropriate life rafts, life jackets, ring buoys, etc., as prescribed by the U.S. Coast Guard, will be maintained on the facility at all times.

(d) Storage Tanks and Production Vessels

The Green Canyon Block 724 wells will be drilled wi th a DP drillship/ DP semisubmersible unit.

Type of Facility Type Of Storage Tank Tank Capacity Number Of Tanks Total Capacity Fluid Gravity

(Api) Total Capacity of all Tanks for Rig Type

Drillship Fuel Oil Storage Tank 5,514 bbls 2 11,028 bbls No. 2 Diesel 12 tanks total= 62,874 bbls Fuel Oil Storage Tank 12,458 bbls 2 24,916 bbls No. 2 Diesel
Fuel Oil Storage Tank 12,065 bbls 2 24,130 bbls No. 2 Diesel
Fuel Oil Settling Tanks 640 bbls 2 1,280 bbls No. 2 Diesel

Fuel Oil Service Tanks 480 bbls 3 1,440 bbls No. 2 Diesel

Fuel Oil Emergency Generator Tank 80 bbls 1 80 bbls No. 2 Diesel

DP Semi Fuel Oil Hull Tanks 4,541 bbls 2 9,082 bbls No. 2 Diesel 7 tanks total= 16,689 bbls

Fuel Oil Hull Tanks 3,392 bbls 2 6,784 bbls No. 2 DieselFuel Oil Deck Day Tank 629 bbls 1 629 bbls No. 2 Diesel

Fuel Oil Deck Settling Tank 164 bbls 1 164 bbls No. 2 Diesel

Fuel Oil Emergency Generator 30 bbls 1 30 bbls No. 2 Diesel



### (e) Pollution Prevention Measures

The drilling rig utilized for these operations will comply with all applicable regula tions regarding pollution prevention and control. The rig ha s a Shipboard Oil Pollution Emergency Plan (SOPEP), which is reviewed and approved annually by the American Bureau of Shipping (ABS). The SOPEP is provided to assist employees in dea ling with an unexpected discharge of oil. Its primary purpose is to set in motion the necessary actions to stop or minimize the discharge of oil and to mitigate its effects. Effective planning en sures that the necessary actions are taken in a structured, logicalm and timely manner.

Pollution prevention measures includ e installation of curbs, gutters, drip pans, and drains on deck areas to collect all contaminants and debris. Most deck drains and some of the joints at the edge of the rig floor go overboard or into the moon pool, respectively. To prevent ocean discharge from the drains there is a dedicated drip pan un der the rotary table. The pipe racks, mud pump room, sack store, and drill floor drains go to a holding tank, which is se rved by a dedicated oily water separator. The well test area, engine room , and other major machinery spaces drains all go to slops tanks, which are served by a large general-serv ice, oily water separa tor. The containment devices are temporary. They are not meant for perm anent storage of waste. On the rare occasion that they contain wastes, they are pumped, moppe d, or cleaned within a short period of time. The chances of damage to a containment structur e during such time as it contains wastes are exceedingly small.

(f) Additional Pollution Prevention Measures

No additional measures are proposed under this plan. The activities proposed in this plan are not located offshore Florida.

(g) Description of Previously Approved Lease Activities

Anadarko has no previously approved we ll locations in Green Canyon Block 724.U.S. Department of the Interior OMB Control Number: 1010-0151 Bureau of Ocean Energy Management OMB Approval Expires: 12/31/14



### OCS PLAN INFORMATION FORM
General Information Type of OCS Plan: Exploration Plan (EP) Devel opment Operations Coordination Document (DOCD)

Company Name: BOEM Operator Number:

Address: Contact Person:

Phone Number:

E-Mail Address: If a service fee is required under 30 CFR 550.125(a), provide the Amount paid Receipt No.

Project and Worst Case Discharge (WCD) Information Lease(s): Area: Block(s): Project Name (If Applicable): Objective(s) Oil Gas Sulphur Salt Onshore Support Base(s):

Platform/Well Name: Total Volume of WCD: API Gravity: Distance to Closest Land (Miles): Volume from uncontrolled blowout: Have you previously provided information to verify the calculations and assumptions for your WCD? Yes No
If so, provide the Control Number of the EP or DOCD with which this information was provided
Do you propose to use new or unusual technology to conduct your activities? Yes No Do you propose to use a vessel with anchors to install or modify a structure? Yes No Do you propose any facility that will serve as a host facility for deepwate r subsea development? Yes No Description of Proposed Activities and Tentative Schedule (Mark all that apply) Proposed Activity Start Date End Date No. of Days Drill and Complete Well Location A Drill and Complete Well Location AA

Description of Drilling Rig Description of Structure Jackup Drillship Caisson Tension leg platform Gorilla Jackup Platform rig Fixed platform Compliant tower

Semisubmersible Submersible Spar Guyed tower

DP Semisubmersible Ot her (Attach Description) Drilling Rig Name (If Known): Floating production system Other (Attach Description)

Description of Lease Term Pipelines From (Facility/Area/Block) To (Facility/Area/Block) Diamet er (Inches) Length (Feet)

Form BOEM- 0137 (December 2011 - Supersedes all previous editi ons of this form which may not be used.) Page 1 of 4OCS PLAN INFORMATION FORM ( CONTINUED ) Include one copy of this page for each proposed well/structure Proposed Well/Structure Location

Well or Structure Name/N umber (If renaming well or structure, reference previous name): Previously reviewed under an approved EP or DOCD? Yes No

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

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

Block No.

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

Anchor Radius (if applicable) in feet: MD (Feet): MD (Feet): MD (Feet): TVD (Feet): TVD (Feet): TVD (Feet):

Anchor Locations for Drilling Rig or Construction Barge ( If anchor radius supplied above, not necessary)
Anchor Name or No. Area Block X Coordinate Y Coordinate Length of Anchor Chain on Seafloor

X = Y =

X = Y =

X = Y =

X = Y =

X = Y =

X = Y =

X = Y =

X = Y =

Form BOEM- 0137 (December 2011 - Supersedes all previous editions of this form which may not be used.) Page 2 of 4OCS PLAN INFORMATION FORM ( CONTINUED ) Include one copy of this page for each proposed well/structure Proposed Well/Structure Location
Well or Structure Name/Number (If renaming well or structure, reference previous name): Previously reviewed under an approved EP or DOCD? Yes No

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

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

Block No.

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

Anchor Radius (if applicable) in feet: MD (Feet): MD (Feet): MD (Feet): TVD (Feet): TVD (Feet): TVD (Feet):

Anchor Locations for Drilling Rig or Construction Barge ( If anchor radius supplied above, not necessary)
Anchor Name or No. Area Block X Coordinate Y Coordinate Length of Anchor Chain on Seafloor

X = Y =

X = Y =

X = Y =

X = Y =

X = Y =

X = Y =

X = Y =

X = Y =

Form BOEM- 0137 (December 2011

- Supersedes all previous editions of this form which may not be used.) Page 2 of 4 GC 724 "AA" 

## x

x 

## n/a

x

G 21817 

### Green Canyon
768



## 107'FNL

5489'FWL


# 2,299,892.78

9,884,053.02

27.22362735

90.97026812

5257' 

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

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

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

Block No.

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

Anchor Radius (if applicable) in feet: MD (Feet): MD (Feet): MD (Feet): TVD (Feet): TVD (Feet): TVD (Feet):

Anchor Locations for Drilling Rig or Construction Barge ( If anchor radius supplied above, not necessary)
Anchor Name or No. Area Block X Coordinate Y Coordinate Length of Anchor Chain on Seafloor

X = Y =

X = Y =

X = Y =

X = Y =

X = Y =

X = Y =

X = Y =

X = Y =

Form BOEM- 0137 (December 2011

- Supersedes all previous editions of this form which may not be used.) Page 2 of 4 GC 724 "AAA" 

## x

x 

## n/a

x

G 21817 

### Green Canyon
768



## 8'FNL

3168'FWL


# 2,299,967.93

9,884,167.99

27.22394019

90.97003120

5257' 

## N/A n/a

### B GENERAL INFORMATION

(a) Applications and Permits

Prior to beginning exploration operations the follo wing application(s) will be submitted for approval:

Application/Permit Issuing Agency Status Permits to Drill BSEE Bureau of Safety and Environmental Enforcement (BSEE) To be submitted

(b) Drilling Fluids

Type of Drilling Fluid Estimated Volume Per Well Water-based (NaCl saturated, seawater, freshwater, barite) for Pump and Dump 16,000 bbls per well**

Synthetic-based (internal olefin, ester) 10,000 bbls per well Oil-based NA

* *The actual volume ordered out will be an estimated 16,000 bbls/well of mud. Once on location this volume will be cut back and mixed with seawater to different desired mud weights which will increase the volume that is discharged at the seafloor. The estimated volume that will be discharged at the seafloor will be approximately 40,000 bbls/well (NOTE: there will be three wells drilled for a total of 120,000 bbls).

(c) New or Unusual Technology

Anadarko does not propose to use any new or unusual tec hnology to drill the well proposed in this plan.

(d) Bonding Statement

The bond requirements for the activities and facilities pr oposed in this EP are satisfied by an area-wide bond furnished and maintained according to 30 CFR pa rt 256, subpart I; NTL No. 2000-G16, “Guidelines for General Lease Surety Bonds,” and National N TL No. 2008-N07, “Supplemental Bond Procedures”.

(e) Oil Spill Financial Responsibility (OSFR)

Anadarko Petroleum Corporation (Company Number 00981) 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 Financia l Responsibility for Covered Facilities”.

(f) Deepwater Well Control Statement

Anadarko Petroleum Corporation (Company Number 0098 1) has the financial capability to drill a relief well and conduct other emergency well control operations if required.

(g) Blowout Scenario

Anadarko prepared this blowout scenario pursuant to guidance provided in NTL No. 2010-N06. The Green Canyon 724 “A” (GC 724 #1) is addressed in this blowout scenario since it is the location with the highest potential worst case discharge (WCD) rate for Green Canyon Block 724. A similar approach would be taken in the event of a blowout for the we lls covered under this pl an. Based on NTL No. 2010-N06 guidance, the maximum hydrocarbon discharge fo r Green Canyon Block 724 is calculated to be 201,530 BOPD.

Purpose This information provides a generic blowout scenario , additional information regarding any potential oil spill, the measures Anadarko Petroleum will take to prevent a blowout, and if necessary, promptly respond to manage a blowout scenario if one occurs . The following information is pursuant with 30 CFR 250.213(g), 250.219, 250.250 and NTL No. 2010-N06.

Background This information has been developed to docum ent the additional information requirements for Exploration Plans as requested by NTL No. 2010-N06. .

I NFORMATION R EQUIREMENTS
Blowout Scenario The GC 724 #1 well will be drilled to the sand objectiv e, as outlined in the Geological and Geophysical Information section of this Plan, utilizing a MODU rig with a marine riser and subsea BOP.

The Blowout Scenario assumes the well has reached its objective TD and a hydrocarbon influx occurs from the objective and ancillary intervals, followed by a well control event. The subsea BOP and marine riser fail, and a blowout occurs at the seabed. The WCD scenario assumes 12-1/4” open-hole across the objective intervals and 13-5/8” casing back to the mudline, as per the attached wellbore schematic (Attachment H-1). The WCD scenario assumes simultaneous flow from the objective zones.

Estimated Flow Rate of the Potential Blowout Category Initial EP Type of Activity Drilling Facility Location (area/block) Green Canyon Block 724 Facility Designation MODU Distance to Nearest Shoreline (miles) 122 Uncontrolled Blowout (volume per day) 201,530 bbls Type of Fluid(s) Crude Oil

a) Potential for the well to bridge over:

Mechanical collapse of the reservoirs in the open-hole section of the wellbore was not considered.

b) Measures to enhance the ability to conduct effect ive and early intervention in the event of a blowout:

The likelihood of surface intervention to stop a blowout is high and based on the following equipment specific to the MODU that has been contracted to do this drilling program:

 ROV Secondary BOP Control System: The BOP is confirmed to have a ROV Intervention Panel and circuits that have the following attributes:

 Hot stab is capable of closing one set of:

- Blind-Shear Rams (one set)- Pipe Rams (one set)

- Unlatch the Lower Marine Riser Package

 ROV hot stab to be function tested in conjunction with the Stump test and tested at the

same rate and pressure as the pump installed on the ROB used by the rig.

 BOP panels also can be operated by an ROV from an independent supply boat in the

event of a loss-of-rig scenario

 Deadman/Autoshear Function: The rig is equi pped with an automated sequence that closes the blind shear rams in the event of any of the following scenarios:

 Inadvertent disconnect of the LMRP

 Loss of both hydraulic pressure and electrical supply from the surface BOP control

system

No human interface is required once these systems are armed.

c) Availability of a rig to drill a relief well:

Per the preliminary Mutual Aid agreements that are being worked between E&P Operators in the Gulf of Mexico, Anadarko will select from the best rig option available in the Gulf of Mexico fleet if and when it is required fo r relief well work. As of March 30, 2014, there were over 20 additional rigs capable of operating under these conditi ons in the Gulf of Mexico. A rig that could be used to drill a relief well is the Transocean Discoverer Clear Leader , which is a drillship capable of drilling in 12,000’ of water without any co nstraints. The rig is currently under contract to Chevron and is on location in Keathley Ca nyon 829 working on the Buckskin Prospect.

There are no nearby platforms from which to drill a relief well. It is not feasible to drill a relief well from land.

d) Rig constraints:

A rig capable of drilling in 5,500’ of water with at least a 10k Stack is required for any relief well operation. The Transocean Discoverer Clear Leader drillship meets these requirements.

e) Time taken to mobilize a rig and drill a relief well:

An estimate of 7–21 days is required to susp end operations on a deepwater GOM well and begin drilling the relief well. This assumes 0–14 days to suspend current operations on an existing well and 7 days to mobilize and be ready to spud the re lief well. The estimated time to drill the relief well is 85 days, for a total estimated time of 92 –106 days from time of blowout to finishing the relief well.f) Assumptions and calculations used in approved or proposed Oil Spill Response Plan:

 The Merlin reservoir simulator and Avalon nodal analysis programs were used to estimate the WCD for this well. Supporting input data can be found on Data Sheets 1, 2, and 3, and Merlin and Avalon files are included as Electronic Attachments 1 and 2. At the seafloor, the estimated worst case discharge for the well is 201,530 BOPD based on the objective sand intervals.

 The maximum total volume during a blowout could potentially be 21,362,180 bbls assuming 106 days for the maximum duration of a blowout, multiplied by the worst case daily uncontrolled blowout volume of 201,530 bbls.

g) Measures taken to reduce the likelihood of a blowout:

 Well Design: Anadarko utilizes a systematic well design process for the planning and construction of a well operation. This pro cess taps into the vast depth of experience Anadarko possesses in the Deep Water drilling ar ena and involves a multi-team peer review of the well design, shallow hazards, and forma tion pressure hazards expected during drilling. This process minimizes the potential for an unplan ned well control event that could lead to a blowout. This process will also include a Registered Professional Engineer review and approval of the final casing design and cementing program.

A detailed pre-drill assessment of formation pr essure provided by Anadarko’s Geological and Geophysical team, along with third-party consulta nts, allows for a mud program that provides an overbalanced mud weight for the safe drilling of the well. For an exploration well, this may also include taking formation pressures to confirm the actual formation pressure during the well construction process to minimize the ri sk of an unplanned well control event. The pore pressure environment is understood due to the nearby offset wells.

The well construction process also requires a systematic review and management acceptance of the start-up preparation work for the rig and crews and the third-party technical audit work on the rig and the rig’s well control equipment. This measures the rig’s ability to handle an unplanned well control event, and it provides assurance the rig can su ccessfully mitigate a loss of well control event and prevent it from becoming a blowout scenario.

 Barrier Philosophy: For all well designs, Anadarko requires and uses a redundant barrier philosophy, which is two independent tested ba rriers including one mechanical barrier, across each flow path during well operations.

For the final casing string (or liner if it is the final string), there shall be two mechanical barriers in addition to cement inside the wellbore.

It is also standard practice to perform pressure tests, in accordance with the law, to confirm integrity on all relevant barriers.In addition, all intermediate and production casing strings retu rned to the wellhead will be locked down prior to proceeding with subsequent wellbore construction.

 BOP and Well Control Equipment: The rig will have an 18-3/4” 15k psi BOP with primary and secondary BOP control systems. The BOP will have been completely recertified, compliant to OEM specifications, by a qualified third-party. Prior to commencement of operations, an independent third-party will verify the subsea BOP is designed for the specific equipment on the rig and the specific well design. [250.416(f)]

 BOP and Well Control Equipment Testing: To ensure effectiveness of the BOP and well control equipment, a testing program will be conducted prior to running the BOP and then during the well operations. This testing pr ogram will provide compliance with current federal regulations for pressure and function t esting. It will also provide periodic assurance on the performance of both primary and secondary BOP control systems including actual interface operations with the ROV and ROV panel.

 Well Control Training and Drills: Anadarko requires key nominated onshore and offshore positions, including rig contractor personnel, hold a WellCAP or equivalent well control training certificate, renewed every two years for the type of floating drilling operation being conducted. Anadarko also monitors compliance for its personnel with th e federal regulations and Sub-Part O for well control training.

A comprehensive program of well control dr ills will be conducted offshore to ensure readiness to identify and manage a well control situation; thereby minimizing the potential for a well control event to lead to a blowout scenario.

h) Arrangements for drilling a relief well:

 Anadarko maintains a master agreement with Wild Well Control, Inc. for advice, management, engineering, well kick pre- a nd post-modeling, and resource support for an unplanned loss-of-well-control event. Wild Well Control, Inc. will be contacted and mobilized, if required, to support Anadarko’s operational team, both at onshore and offshore locations.

 The conceptual relief well design is similar to the design of the GC 724 #1 well with respect to identical casing weights, grades, and setti ng points. A site clearance letter has been prepared that includes an assessment of the sp ecific seafloor and subsurface hazards for an area within a 2,000 ft radius of the primary location, within which a relief well could be drilled. There is negligible potential for hi gh-density chemosynthetic or other benthic communities within this 2,000 ft radius. Depe nding on the nature of the blowout scenario, well geometry, and total depth required to inte rsect the blowout, previously submitted surface locations and/or additional surf ace locations will be submitted and reviewed to determine themost appropriate location of the relief well.

 Anadarko’s philosophy is to carry adequate inve ntory in stock to drill a complete well(s) from surface to TD. Back-up long-lead equivalent to the original well design will be carried in stock to allow a rapid response. This in cludes a spare deepwater subsea wellhead system, the large OD casing (36”, 28”, 22”, 18”, 16”), and required connectors. Smaller OD casing (13-5/8”, 11-7/8”, and 9-7/8”) is considered widely available on the ground in the GOM and would be resourced out of existing i nventory or from suppliers as required.

 Existing service agreements are in place for support services, including drilling fluids, casing running, cementing, ROVs, solids control, mud logging, directional drilling, LWD/MWD, logging, boats, and helicopters.

 Specialist services for range finding to drill the re lief well in close proximity to the original wellbore at the reservoir depth will be provide d through Vector Magnetics, LLC. Sperry Drilling/Halliburton and Schlumberger have in-house personnel to supplement Vector Magnetics, LLC, under our existing directional drilling agreements.

### C GEOLOGICAL AND GEOPHYSICAL INFORMATION

(a) Geological Description

Discussions regarding geologic information are consid ered proprietary and have been omitted from this public copy of the EP, along with the attachments.

(b) Structure Contour Maps

Current structure maps drawn to the top of each productive hydrocarbon sand showing the entire lease block, the surface locations of each well and locations of geological cross-sections, are enclosed as Attachment C-1.

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

Interpreted seismic lines are enclosed as Attachment C-2.

(d) Geological Structure Cross-Sections

Interpreted geological structure cross-sections show ing the location and depth of each proposed well are enclosed as Attachment C-3.

(e) Shallow Hazards Report

A Shallow Hazards Report prepared by Fugro GeoServi ces, Inc. was previously submitted with the Initial Exploration Plan for Green Canyon Block 768, which covers the proposed well’s surface locations.

(f) Shallow Hazards Assessment

Shallow Hazards Site Clearance Letters for the propo sed well’s surface locations in Green Canyon Block 768 are enclosed as Attachment C-4.

Since the wells have a surface location with 500’ of the previously approved GC 768 BB well (drilled as the GC 768 #004), the three wells proposed under this pl an will utilize the Site Clearance Letter from the GC 768 BB location.

(g) High-resolution Seismic Lines

High resolution seismic lines are enclosed as Attachment C-5.

(h) Stratigraphic Column

A generalized stratigraphic column depicting the wells from the seafloor to total depth is included as Attachment C-6.

(i) Time Vs. Depth Tables

The proposed activities under this EP are not considered to be in areas where there is no well control. Therefore, a seismic travel time versus dept h table is not required per NTL No. 2008-G04.

### D HYDROGEN SULFIDE INFORMATION

The GC 724 wells will only penetr ate supra-salt sections previously penetrated by four of the GC 768 wells (within approximately 250’ of the surface location of proposed well) and had no recorded amounts of Hydrogen Sulfide. The objectiv e interval has been pene trated by all of the Ticonderoga Field wells mentioned above, the closest being the Kerr McGee (Anadarko) GC 768-3 (API # 608114050200) well at a distance of 2,500’. None of these penetrations encountered any Hydrogen Sulfide w ithin the aforementioned section. Since no (H 2 

### S) was encountered in any of these wells we request th e area be classified as a "zone where the absence of H2s has been confirmed.”

### E BIOLOGICAL, PHYSICAL, AND SOCIOECONOMIC INFORMATION

(a) Chemosynthetic Communities Report

The seafloor disturbing activities proposed in this plan are in approximately 5,257’of water. The wells will be drilled with a DP Drillship or DP Semisubmersible drilling unit.



### Maps

A map prepared using 3-D seismic data to depi ct bathymetry, seafloor and shallow geological features, and surface location of the propos ed well is included in Section A.

Analysis

Features or areas that could support high-density chemosynthetic communities are not located within 2000 feet of each proposed muds and cuttings discharge location.

Features or areas that could support high-density chemosynthetic communities are not located within 250 feet of any se afloor disturbances.

(b) Topographic Features Map

The proposed activities are not with in 1,000 feet of a no-ac tivity zone or within the 3-mile radius zone of an identified topographic feature. Th erefore, no map is requ ired per NTL No. 2008-G04.

(c) Topographic Features Statement (Shunting)

Anadarko does not plan to drill more than two wells from the same surface location within the Protective Zone of an identifie d topographic feature. Theref ore, the topographic features statement required by NTL No. 200 8-G04 is not applicable.

(d) Live Bottoms (Pinnacle Trend) Map

The activities proposed in this pl an are not within 200 feet of any pinnacle trend feature with vertical relief equal to or greater than 8 f eet. Therefore, no map is required per NTL No. 2008- G04.

(e) Live Bottoms (Low Relief) Map

The activities proposed in this plan are not within 100 feet of any live bottom low relief features. Therefore, no map is required per NTL No. 2008-G04.

(f) Potentially Sensitive Biological Features



### The activities proposed in this plan are not within 200 feet of any potentia lly sensitive biological features. Therefore, no map is required per NTL No. 2008-G04.

### (g) Remotely Operated Vehicle (ROV) Monitoring Survey Plan

Green Canyon Block 724 is located within Deepwater Grid Area 10. This grid is considered to have “adequate ROV survey coverage”, and th erefore, under the guidance set out in NTL No. 2008-G06, a Remotely Operated Vehicle Mon itoring Survey Plan is not required.

(h) Threatened and Endangered Species Information

Under Section 7 of the Endangered Species Act (ESA) all federal ag encies must ensure that any actions they authorize, fund, or carry out are not li kely to jeopardize the continued existence of a listed species, or destroy or adversely modify its designated critical habitat.

In accordance with the 30 CFR 250, Subpart B, effective May 14, 2007, and further outlined in Notice to Lessees (NTL) 2008-G04, lessees/operators are require d to address site-specific information on the presence of federally listed threatened or endangere d species and critical habitat designated under the ESA and marine ma mmals protected under the Marine Mammal Protection Act (MMPA) in the area of proposes activities under this plan.

Currently there are no designated critical habitats for the listed species in the Gulf of Mexico Outer Continental Shelf; however, it is possible th at one or more of thes e species could be seen in the area of our operations. The following table reflects the Federally-listed endangered and threatened species in the lease ar ea and along the northern Gulf coast:pecies Scientific Name Status Potential Presence Critical Habitat Designated in Gulf of Mexico Lease Area Coastal

Marine Mammals

Sei whale Balaenoptera borealis E X a -- None

Blue whale Balaenoptera musculus E X a -- None

Fin whale Balaenoptera physalus E X a -- None North Atlantic right whale Eubalaena glacialis E X a -- None Humpback whale Megaptera novaeangliae E X a -- None Sperm whale Physeter macrocephalus E X -- None

West Indian manatee Trichechus manatus latirostris E -- X Florid a (Peninsular)

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.

The Environmental Impact Analysis in Section N of this plan further discusses potential impacts and mitigation measures related to threatened and endangered species.

(i) Archaeological Report

Green Canyon Block 724 is not located in an area designated as having high archaeological potential and, as such, an Archaeological Report is not re quired per NTL No. 2011-JOINT-G01. However, an Archaeological Report prepared by Fugro Geoservices, Inc covering the proposed Green Canyon Block 724 well’s surface locations inGreen Canyon Block 768 was previously submitted along with the Supplemental Exploration Plan Control No. S7604. The survey was conducted in accordance with the latest guidelines established by the BOEMRE in 2011.

(j) Air and Water Quality Information

This EP does not propose activities for which the State of Flor ida is an affected State. Therefore, the discussion required per NTL 2008-G04 is not applicable to this EP.(k) Socioeconomic Information

The activities proposed in this plan are not located offshore Florida. Therefore, socioeconomic information required per NTL 2008-G04 is not applicable to this EP.

### F WASTE AND DISCH ARGE INFORMATION

The following estimates were prepared utilizing Anad arko’s experience with si milar drilling operations. Estimated maximum discharge rates are reflected below. Projected amounts may vary during the course of drilling and/or completion operations.

(a) Projected Generated Wastes

Type of Waste Composition Projecte d Amount Treatment/Storage/Disposal Synthetic-based drilling fluids Synthetic-based drilling muds 10,000 bbls/well Re-use and/or transport to shore in DOT approved containers to Fourchon, Louisiana and on to base/transfer station. If recycled, returned to vendor (Bariod or MI). Cuttings wetted with synthetic-based fluids Cuttings coated with synthetic drilling muds/fluids, including drilled out cement 2,000 bbls/well Treated and discharge overboard *Note, an estimated 5-10% of cuttings may be transported to shore in tanks and/or cutting boxes and on to the base/transfer station if oil still remains

. Water-based drilling fluids Water based drilling muds (NaCl saturated, seawater, freshwater, barite) 40,000 bbls/well** Discharge overboard or at seafloor

Cuttings wetted with water-based fluids Cuttings coated with water-based drilling muds/fluids 2,000 bbls/well Discharge overboard

Chemical product waste (well treatment fluids) Ethylene glycol Methanol 1,500bbls total

375 bbls total Transport to shore in DOT approved containers to Fourchon, Louisiana for pick up. Completion Fluids Brine, spent acid, prop sand, debris 3,000 bbls/well Transport to shore in DOT approved containers to Fourchon, Louisiana and on to Newpark Base. Non-pollutant completion fluids Low density uninhibited completion brines 5,000 bbls/well Discharge overboard

Workover fluids Brine, spent acid, prop sand, debris 3,000 bbls/well Transport to shore in DOT approved containers to Fourchon, Louisiana and on to Newpark Base.

Trash and debris Refuse generated during operations 750 bbls total Transport to sh ore in disposal bags by vessel to shorebase for pickup by municipal operations. Sanitary Wastes* Treated human body
waste 2,250,000 gals total Chlorina te and discharge overboard

Domestic Waste* Gray water 2,250,000 gals total Chlorina te and discharge overboard Deck drainage Platform washings and rainwater 1,575,000 bbls total Treat for oil and grease and discharge overboard Produced water N/A N/A N/A Desalinization Unit S eawater 157,500 bbls total Discharge overboard Wash water Drill water (fresh) 22, 500 bbls total Discharge overboard Blowout preventer fluid Blend (3% Stack Magic & Filtered Fresh Water) 59,464 gals total Discharge at seafloor

Ballast water Seawater 47,650 m3/year Discharge overboard Bilge water Seawater 142,650 bbls total Discharge overboard through 15 ppm equipment Excess cement at the seafloor*** Nitrified cement slurry 1,500 bbl s/well Discharge at seafloorFire water Seawater 137,142 bbls/ day/well Discharge overboard Cooling water Seawater 137,142 bbls/ day/well Discharge overboard Produced Sand N/A N/A N/A Used oil Excess oil from engine s 1,613 bbls total Transport in DOT approved containers to shore for recycling *The rig is designed for maximum personnel capacity of 200 pe ople. The discharge rates are based off of maximum personnel capacity but will generally not have this many pe rsonnel onboard during drilling and/or completion operations.

* *The actual volume ordered out will be an estimated 16,000 bbls/well of mud. Once on location this volume will be cut back and mixed with seawater to different desired mud weights which w ill increase the volume that is discharged at the seafloor. Th e estimated volume that will be discharged at the seafloor wi ll be approximately 40 ,000 bbls/well (NOTE: ther e will be three well s drilled for a total of 120,000 bbls).

(b) Projected Ocean Discharges Type of Waste Total Amount to be Discharged Discharge Rate Discharge Method

Sanitary Wastes* 2,250,000 gals to tal 25 gals per person daily Chlo rinate and discharge overboard Domestic waste* 2,250,000 gals to tal 25 gals per person daily Chlori nate and discharge overboard Deck drainage 1,575,000 bbls total 3500 bbls/da y Treat for oil and grease and discharge Blowout preventer fluid 59,464 gals total 925 gals/week/well; Vents on a weekly basis Discharge at seafloor

Desalinization Unit 157,500 bbls total 350 bbls/day Discharge overboard Wash water 22,500 bbls total 50 bbls/day Discharge overboard Ballast water 47,650 m3/year Not continuous Discharge overboard Bilge water 142,650 bbls tota l 317 bbls/day Discharge overboard through 15 ppm equipment Excess cement at the seafloor** 4,500 bbls total 20 bbls/min Discharge at seafloor

Fire water 61,713,900 bbls total 137, 142 bbls/day Discharge overboard Cooling water 61,713,900 bbls total 137,142 bbls/day Discharge overboardCuttings wetted with Waterbased fluids** 6,000 bbls total 1,000 bbls/hr max Discharge overboard

Water-based drilling fluids** 120,000 bbls total** 1,000 bbls/hr max Disc harge at seafloor or overboard

Cuttings wetted with Synthetic-based fluids** 8,000 bbls total NA Treated and discharge overboard *Note, an estimated 5-10% of cuttings may be transported to shore in tanks and/or cutting boxes and on to the base/transfer station if oil still remains

. Non-pollutant completion fluids 15,000 bbls total 100 bbl/hour Discharge overboard

*The rig is designed for maximum personnel capacity of 200 pe ople. The discharge rates are based off of maximum personnel capacity but will generally not have this many pe rsonnel onboard during drilling and/or completion operations.

* *The actual volume ordered out will be an estimated 16,000 bbls/well of mud. Once on location this volume will be cut back and mixed with seawater to different desired mud weights which w ill increase the volume that is discharged at the seafloor. Th e estimated volume that will be discharged at the seafloor wi ll be approximately 40 ,000 bbls/well (NOTE: ther e will be three well s drilled for a total of 120,000 bbls).
(c) Modeling Report

The proposed activities under this plan do not meet the U.S. Environmental Protection Agency requirements for an individual NPDES permit. Th erefore, modeling report requirements per NTL No. 2008-G04 is not applicable to this EP.

### G AIR EMISSIONS INFORMATION

(a) Screening Questions

Screening Questions for EP’s Yes No Is any calculated Complex Total (CT) Emission amount (in tons) associated with your proposed exploration activities more than 90% of the amounts calculated using the following formulas: CT = 3400D 2/3 for CO, and CT = 33.3D for the other air pollutants (where D = distance to shore in miles)? No

Do your emission calculations include any emission reduction measures or modified emission factors? Yes

Are your proposed exploration activities located east of 87.5 W longitude? No Do you expect to encounter H2S at concentrations greater than 20 parts per million (ppm)? No Do you propose to flare or vent natural gas for more than 48 continuous hours from any proposed well? No

Do you propose to burn produced hydrocarbon liquids? No

(b) Emissions Worksheets

Air emission worksheets have been prepared utiliz ing the maximum horsepower rating from an Anadarko contracted DP drillship, the Noble Bob Douglas . The Noble Bob Douglas has six main engines. The average number of engines on-line at once will be four engines. Rigs typically do not operate at maximum horsepower capacity or engine load, therefore Anadar ko has opted to calculate the plan emission amounts based on the total horsepower rating and 50% average e ngine load. A different rig may be utilized (DP drillship or DP semi-submersible); but the horsepower rating, average engine load, and air emissions will be equal to, or less than, the calculated plan em ission amounts shown on the following pages. Air emission worksheets are enclosed as Attachment G-1.

(c) Summary Information

The following tables summarize information regarding the peak year emissions generated from the Plan Emissions and Complex Total Emissions:

If drilled with a DP Drillship or DP Semi (Horsepow er equal to or less than the Noble Bob Douglas): Air Pollutant Plan Emission Amounts 1 (tons) Calculated Exemption Amounts 2 (tons) Calculated Complex Total Emission Amounts 3 (tons) Particulate matter (PM) 69.91 4062.60 N/A Sulphur dioxide (SO 2 ) 320.73 4062.60 N/A Nitrogen oxides (NO x ) 2405.32 4062.60 N/A Volatile organic compounds (VOC) 73.90 4062.60 N/A Carbon monoxide (CO) 535.98 83634.50 N/A

The air emission calculations were calculated by:

Jill Fowler Regulatory Analyst (832) 636-1554 jill.fowler@anadarko.comEXPLORATION PLAN (EP)AIR QUALITY SCREENING CHECKLISTOMB Control No. 1010-0151OMB Approval Expires: 12/31/14COMPANYAnadarko Petroleum CorporationAREAGreen CanyonBLOCK724 & 768LEASEOCS-G 34557 & 21817PLATFORMWELLA, AA, AAACOMPANY CONTACTJill FowlerTELEPHONE NO.832-636-1554REMARKSDrill and complete 3 wells totalFORM BOEM-0138(December 2011 - Supersedes all previous versions of this form which may not be used).Page 1 of 8EMISSIONS FACTORSFuel Usage Conversion FactorsNatural Gas Turbines Natural Gas Engines Diesel Recip. Engine REF. DATESCF/hp-hr 9.524 SCF/hp-hr 7.143 GAL/hp-hr 0.0483AP42 3.2-1 4/76 & 8/84Equipment/Emission Factorsunits PM SOx NOx VOC CO REF. DATENG Turbines gms/hp-hr 0.00247 1.3 0.01 0.83AP42 3.2-1& 3.1-1 10/96NG 2-cycle lean gms/hp-hr 0.00185 10.9 0.43 1.5AP42 3.2-1 10/96NG 4-cycle lean gms/hp-hr 0.00185 11.8 0.72 1.6AP42 3.2-1 10/96NG 4-cycle rich gms/hp-hr 0.00185 10 0.14 8.6AP42 3.2-1 10/96Diesel Recip. < 600 hp. gms/hp-hr 1 1.468 14 1.12 3.03AP42 3.3-1 10/96Diesel Recip. > 600 hp. gms/hp-hr 0.32 1.468 11 0.33 2.4AP42 3.4-1 10/96Diesel Boiler lbs/bbl 0.084 2.42 0.84 0.008 0.21AP42 1.3-12,14 9/98NG Heaters/Boilers/Burners lbs/mmscf 7.6 0.593 100 5.5 84P42 1.4-1, 14-2, & 147/98NG Flares lbs/mmscf 0.593 71.4 60.3 388.5AP42 11.5-1 9/91Liquid Flaring lbs/bbl 0.42 6.83 2 0.01 0.21AP42 1.3-1 & 1.3-3 9/98Tank Vapors lbs/bbl 0.03E&P Forum 1/93Fugitives lbs/hr/comp. 0.0005API Study 12/93Glycol Dehydrator Vent lbs/mmscf 6.6La. DEQ 1991Gas Venting lbs/scf 0.0034Sulphur Content Source Value UnitsFuel Gas 3.33 ppmDiesel Fuel 0.4 % weightProduced Gas( Flares) 3.33 ppmProduced Oil (Liquid Flaring) 1 % weightFORM BOEM-0138(December 2011 - Supersedes all previous versions of this form which may not be used).Page 2 of 8EMISSIONS CALCULATIONS 1ST YEARCOMPANY AREA BLOCK LEASE PLATFORM WELL CONTACT PHONE REMARKSAnadarko Petroleum CorGreen Canyon 724 & 768 OCS-G 34557 & 21817 A, AA, AAA Jill Fowler 832-636-1554OPERATIONS EQUIPMENT RATING MAX. FUEL ACT. FUEL RUN TIME MAXIMUM POUNDS PER HOUR ESTIMATED TONSDiesel Engines HP GAL/HR GAL/DNat. Gas Engines HP SCF/HR SCF/DBurners MMBTU/HR SCF/HR SCF/D HR/D DAYS PM SOx NOx VOC CO PM SOx NOx VOC CODRILLING PRIME MOVER>600hp diesel 64370 1554.5355 50% 37308.85 24 60 22.69 104.07 779.81 23.39 170.14 16.33 74.93 561.47 16.84 122.50PRIME MOVER>600hp diesel 0 0 0.00 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00PRIME MOVER>600hp diesel 0 0 0.00 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00PRIME MOVER>600hp diesel 0 0 0.00 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00BURNER diesel 0 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00AUXILIARY EQUIP<600hp diesel 0 0 0.00 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.003 trips/week VESSELS>600hp diesel(crew) 14805 715.0815 17161.96 6 26 10.44 47.87 358.71 10.76 78.26 0.81 3.73 27.98 0.84 6.102 trips/week VESSELS>600hp diesel(supply) 9266 447.5478 10741.15 6 17 6.53 29.96 224.51 6.74 48.98 0.33 1.53 11.45 0.34 2.50VESSELS>600hp diesel(tugs) 0 0 0.00 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00FACILITY DERRICK BARGE diesel 0 0 0.00 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00INSTALLATION MATERIAL TUG diesel 0 0 0.00 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00VESSELS>600hp diesel(crew) 0 0 0.00 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00VESSELS>600hp diesel(supply) 0 0 0.00 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00MISC. BPD SCF/HR COUNTTANK- 0 0 0 0.00 0.00DRILLING OIL BURN 0 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00WELL TEST GAS FLARE 625000 24 0 0.37 44.63 37.69 242.81 0.00 0.00 0.00 0.002014 YEAR TOTAL39.65 182.27 1407.66 78.58 540.20 17.48 80.19 600.89 18.03 131.10EXEMPTIONCALCULATIONDISTANCE FROM LAND INMILES4062.60 4062.60 4062.60 4062.60 83634.50122.0AverageEngineLoad %FORM BOEM-0138(December 2011 - Supersedes all previous versions of this form which may not be used).Page 3 of 8EMISSIONS CALCULATIONS 1ST YEARCOMPANY AREA BLOCK LEASE PLATFORM WELL CONTACT PHONE REMARKSAnadarko Petroleum CorGreen Canyon 724 & 768 OCS-G 34557 & 21817 A, AA, AAA Jill Fowler 832-636-1554OPERATIONS EQUIPMENT RATING MAX. FUEL ACT. FUEL RUN TIME MAXIMUM POUNDS PER HOUR ESTIMATED TONSDiesel Engines HP GAL/HR GAL/DNat. Gas Engines HP SCF/HR SCF/DBurners MMBTU/HR SCF/HR SCF/D HR/D DAYS PM SOx NOx VOC CO PM SOx NOx VOC CODRILLING PRIME MOVER>600hp diesel 64370 1554.5355 50% 37308.85 24 240 22.69 104.07 779.81 23.39 170.14 65.33 299.72 2245.86 67.38 490.01PRIME MOVER>600hp diesel 0 0 0.00 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00PRIME MOVER>600hp diesel 0 0 0.00 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00PRIME MOVER>600hp diesel 0 0 0.00 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00BURNER diesel 0 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00AUXILIARY EQUIP<600hp diesel 0 0 0.00 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.003 trips/week VESSELS>600hp diesel(crew) 14805 715.0815 17161.96 6 103 10.44 47.87 358.71 10.76 78.26 3.22 14.79 110.84 3.33 24.182 trips/week VESSELS>600hp diesel(supply) 9266 447.5478 10741.15 6 69 6.53 29.96 224.51 6.74 48.98 1.35 6.20 46.47 1.39 10.14VESSELS>600hp diesel(tugs) 0 0 0.00 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00FACILITY DERRICK BARGE diesel 0 0 0.00 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00INSTALLATION MATERIAL TUG diesel 0 0 0.00 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00VESSELS>600hp diesel(crew) 0 0 0.00 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00VESSELS>600hp diesel(supply) 0 0 0.00 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00MISC. BPD SCF/HR COUNTTANK- 0 0 0 0.00 0.00DRILLING OIL BURN 0 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00WELL TEST GAS FLARE 625000 24 4 0.37 44.63 37.69 242.81 0.02 2.14 1.81 11.662015 YEAR TOTAL39.65 182.27 1407.66 78.58 540.20 69.91 320.73 2405.32 73.90 535.98EXEMPTIONCALCULATIONDISTANCE FROM LAND INMILES4062.60 4062.60 4062.60 4062.60 83634.50122.0AverageEngineLoad %FORM BOEM-0138(December 2011 - Supersedes all previous versions of this form which may not be used).Page 3 of 8EMISSIONS CALCULATIONS 1ST YEARCOMPANY AREA BLOCK LEASE PLATFORM WELL CONTACT PHONE REMARKSAnadarko Petroleum CorGreen Canyon 724 & 768 OCS-G 34557 & 21817 A, AA, AAA Jill Fowler 832-636-1554OPERATIONS EQUIPMENT RATING MAX. FUEL ACT. FUEL RUN TIME MAXIMUM POUNDS PER HOUR ESTIMATED TONSDiesel Engines HP GAL/HR GAL/DNat. Gas Engines HP SCF/HR SCF/DBurners MMBTU/HR SCF/HR SCF/D HR/D DAYS PM SOx NOx VOC CO PM SOx NOx VOC CODRILLING PRIME MOVER>600hp diesel 64370 1554.5355 50% 37308.85 24 150 22.69 104.07 779.81 23.39 170.14 40.83 187.33 1403.66 42.11 306.25PRIME MOVER>600hp diesel 0 0 0.00 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00PRIME MOVER>600hp diesel 0 0 0.00 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00PRIME MOVER>600hp diesel 0 0 0.00 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00BURNER diesel 0 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00AUXILIARY EQUIP<600hp diesel 0 0 0.00 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.003 trips/week VESSELS>600hp diesel(crew) 14805 715.0815 17161.96 6 64 10.44 47.87 358.71 10.76 78.26 2.00 9.19 68.87 2.07 15.032 trips/week VESSELS>600hp diesel(supply) 9266 447.5478 10741.15 6 43 6.53 29.96 224.51 6.74 48.98 0.84 3.87 28.96 0.87 6.32VESSELS>600hp diesel(tugs) 0 0 0.00 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00FACILITY DERRICK BARGE diesel 0 0 0.00 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00INSTALLATION MATERIAL TUG diesel 0 0 0.00 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00VESSELS>600hp diesel(crew) 0 0 0.00 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00VESSELS>600hp diesel(supply) 0 0 0.00 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00MISC. BPD SCF/HR COUNTTANK- 0 0 0 0.00 0.00DRILLING OIL BURN 0 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00WELL TEST GAS FLARE 625000 24 2 0.37 44.63 37.69 242.81 0.01 1.07 0.90 5.832016 YEAR TOTAL39.65 182.27 1407.66 78.58 540.20 43.68 200.39 1502.57 45.95 333.43EXEMPTIONCALCULATIONDISTANCE FROM LAND INMILES4062.60 4062.60 4062.60 4062.60 83634.50122.0AverageEngineLoad %FORM BOEM-0138(December 2011 - Supersedes all previous versions of this form which may not be used).Page 3 of 8SUMMARYCOMPANY AREA BLOCK LEASE PLATFORM WELLAnadarko Petrol Green Canyon 724 & 768 OCS-G 34557 & 21817A, AA, AAAEmitted SubstanceYearPM SOx NOx VOC CO2014 17.48 80.19 600.89 18.03 131.102015 69.91 320.73 2405.32 73.90 535.982016 43.68 200.39 1502.57 45.95 333.432017 0.00 0.00 0.00 0.00 0.002018 0.00 0.00 0.00 0.00 0.002019 0.00 0.00 0.00 0.00 0.002020 0.00 0.00 0.00 0.00 0.002021 0.00 0.00 0.00 0.00 0.002022 0.00 0.00 0.00 0.00 0.002023 0.00 0.00 0.00 0.00 0.00Allowable4062.60 4062.60 4062.60 4062.60 83634.50FORM BOEM-0138(December 2011 - Supersedes all previous versions of this form which may not be used).Page 8 of 8

### H OIL SPILL INFORMATION

(a) Oil Spill Response Planning

(i) OSRP Information

All the proposed activities and facilities in this EP are covered by the Regional Oil Spill Response Plan (OSRP) approved on Septembe r 25, 2013 for Anadarko Pe troleum Corporation and its subsidiaries, Anadarko US Offshore Corporation and Anadarko E&P Company L.P. (Company Numbers 00981, 02219 and 00148, respectivel y) in accordance with 30 CFR Part 254.

(ii) Spill Response Sites

Primary Response Equipment Location(s) Preplanned Staging Location(s) 

### Houma, Louisiana Harvey, Louisiana Venice, Louisiana Lake Charles, Louisiana Galveston, Texas Fourchon, Louisiana Harvey, Louisiana Venice, Louisiana Cameron, Louisiana Galveston, Texas

(iii) OSRO Information

Anadarko maintains a contract w ith Clean Gulf Associates (CGA) for spill response equipment. Various equipment locations are staged throughout the Gulf of Mexico. CGA equipment can be referenced on their website: http://www.cleangul fassoc.com/. Personnel would be obtained from the Marine Spill Response Corporation’s (MSRC) STARS network, including a supervisor to operate the equipment.

In addition Anadarko has a contract with the Marine Spill Response Co rporation (MSRC) for spill response equipment. MSRC stages equipm ent throughout the Gulf of Mexico and has recently completed a large expansion of its resources, with particular focus on deepwater. The expansion is known as “Deep Blue”. 

### MSRC capabilities and a complete equipment listing are available online at: http:// www.msrc.org/.

Anadarko is also a member of the Marine Well Containment Co mpany (MWCC), which provides access to containment response capabilities and includes subsea dispersant injection equipment.

### (iv) Worst-Case Scenario Determination

Category Regional OSRP EP Type of Activity Exploratory Exploratory Facility Location (area/block) GC 683 GC 724
Facility Designation GC 683 “G” GC 724 “A” Distance to Nearest Shoreline 120 miles 122 miles
Storage Tanks (total) N/A N/A Flowlines (on facility) N/A N/A Pipelines N/A N/A Uncontrolled Blowout 410,000 bopd* 201,530 BOPD Type of Oil(s) Oil Oil API Gravity 28.9 o 30.9 o -32.2 o

*The volume denoted in the Regional OSRP is higher t han the NTL No. 2010-N06 (403,608 bopd) calculations approved under EP Plan Control No. S-7623. Anadarko elected to denot e a higher volume in the Regional OSRP for planning purposes to demonstrate equipment re sponse capabilities per previous discussions with Mr. Mike Tolbert.



### Anadarko has determined that the worst-case scenario from the ac tivities proposed in this Initial EP do not supersede the worst-case scenario for Green Canyon Block 683.

Since Anadarko has the cap ability to respond to the worst-case spill s cenario included in our Regional OSRP, and since the worst-case scenar ios determined for our EP do not replace the worst-case scenario in our Regional OSRP last approved on September 25, 2013, I hereby certify that Anadarko has the capability to respond, to th e maximum extent practicable, to a worst-case discharge, or a substantial threat of such a discha rge, resulting from the ac tivities proposed in our EP.

(b) Worst-Case Discharge Volume Assumptions

Worst-case discharge (WCD) calculations and assump tions within this section utilized guidelines and requirements pursuant with NTL No. 2010-N 06. The following information summarizes the WCD scenario and assumptions for Green Canyon Block 724:

Discussions regarding geologic information are considered proprietary and have been omitted from this public copy of the EP , along with the attachments.

(c) Oil Spill Response Discussion

For the purpose of NEPA analysis, the largest spill volume originating from the proposed activity would be an uncontrolled blowout of the well during drilli ng operations at 201,530 BOPD with an API gravity of 30.9 o 

### -32.2 o 

### . A discussion of the blowout scenario from this proposed activity is included within this Initial EP in accordance with NTL No. 2010-N06.

### Land Segment and Resource Identification Modeling

Trajectory of a spill and the probability of its impacting a land segment have been projected utilizing information in the Oil Spill Risk An alysis Model (OSRAM) for the Central Gulf of Mexico. Additional information may be referenced in the “Oil-Spill Risk Analysis: Contingency Planning Statistics for Gulf of Mexico OC S Activities” (OCS Report MMS 2004-026), using the average conditional probability for 3, 10, and 30 day impacts.

Green Canyon Block 724 is lo cated within Launch Area 45. According to the BOEMRE OSRAM, the trajectory indicates a 4% probabili ty of potential impact to the shoreline in Cameron Parish, Louisiana. The results are shown in Table H-2.

Cameron Parish is identified as the most probable potential impacted parish or county within the Gulf of Mexico for this operation. Cameron Parish is located in Louisian a and includes Cameron Prairie National Wildlife Refuge (NWR), East C ove Unit (a part of the Cameron Prairie NWR), Lacassine NWR, and Sabine NWR.

Response

Anadarko will make every effort to respond to the worst-case discharge as effectively as possible. Response equipment available to respond to the worst-case discharge and the estimated time of a spill response from oil spill detecti on to equipment deployment on-site is included in Table H-3. The table estimates individual times needed for procurement, load out, travel time to the site and deployment. In the event of an actual incident equipment and times can vary.

For the purpose of response scenario discussion, an uncontrolled blowout of the well would be considered the largest potential spill vol ume at 201,530 BOPD. An AD IOS weathering model was run based on a similar type of oil expected to be produced from this well. Based on this information, approximately 16% (32,245 bbl s) of the initial volume would be evaporated/dispersed within 24 hours.

If approved and appropriate, 4 sorties (8,000 ga llons) from the Basler ai rcraft and 8 sorties (9,600 gallons) from two DC-3 aircrafts could disperse approximately 7,540 barrels of oil.

If the conditions are appropriate, and the necessary approvals and permits have been obtained, in-situ burning may be utilized. Based on in -situ burn operations du ring Deepwater Horizon, approximately 5% (10,267 bbls) of the total in itial worst case discharge could be burned.

Although unlikely in a spill lastin g thirty (30) days, potential shoreline impact in Cameron Parish, Louisiana could occur depending on e nvironmental conditions (wind, currents and temperature) at the time of an incident. Nearsh ore response may include the use of shoreline boom on beach areas, or protection/sorbent boom on vegetated areas. Surveillance and real time trajectories would aide in determining the most appropriate strategies to respond to a spill.

Table H.3 provides an example of offshore a nd nearshore equipment, response times, and personnel to respond to a spill of 169,285 bbls, which is the estima ted amount that would remain

### considering natural evaporation/ dispersion at 24 hours. This amount could be further reduced through the application of aeria l and subsea dispersants, and in-situ burning provided such applications/actions were approved.

Anadarko’s contingency plan for de aling with this worst-case disc harge would be to activate its Spill Management Team and equipment resources as described in its Gulf of Mexico Regional Oil Spill Response Plan (OSRP) and provide con tinuous support for the duration of the event. Response resources are activated and supplemen ted according to need. These resources would remain engaged in the response until the incident is deemed complete or until released by Unified Command.

Anadarko is also a member of the Marine Well Containment Co mpany (MWCC), which provides access to containment response capabilities and includes subsea dispersant injection equipment.

In the event of a blowout, Anadarko may:

1. Evacuate personnel, if necessary. Deploy emer gency responders in an effort to preserve human life, if necessary.

2. Assess the damage and attempt to stop the flow at the source, if safe to do so, to reduce the amount of oil discharged. 3. Notify agencies.

4. Assess the amount of oil that has been sp illed and calculate add itional potential of oil flow. A continuous aerial surveillance program w ould be used to assess the growth of the slick and the volume of oil on the water. Ob servations of the si ze of the slick on the water, combined with observations at the s ource, would be used to provide a constant update. Additional potential to release fuel from the remaining tanks onboard the dynamically positioned (DP) semi-submersible drilling rig would be determined by marine surveyors. Operations and Unifie d Command would continue to assess the adequacy of response equipment capacities based on this continually updated mass balance.

5. Convene the Spill Management Team (SMT). Organize Unified Command and establish objectives and priorities.

6. Monitor the oil spill with aerial surveillance and obtain tr ajectories. If oil is seaward bound, going away from land, discuss additiona l strategies with Unified Command.

7. If oil is moving in the direction of a shoreline and weather co nditions are favorable, request approval to u tilize dispersants.

a. Prior to commencing application operati ons, conduct an on-site survey in consultation with natural resource specialists to determ ine if any threatened or endangered species

### are present in the projected application ar ea or otherwise at risk from dispersant application.

b. Upon approval, mobilize one Basler aircraft and two DC-3 aircrafts from Houma, with surveillance aircraft and spotter. Mobili ze MSRC contracted aircraft(s) if needed. Rotate aircraft, spraying the leading edge of the spill and working back to the source. Monitor/sample for effectiveness (U SCG SMART Team). Truck additional dispersants from CGA/MSRC stockp ile to Houma, if necessary.

c. Dispersants are most effective when app lied as soon after discha rge as possible, since weathering of the oil decreas es dispersant effectiveness. The estimated window of opportunity for most effectiv e use of dispersants is w ithin 48-72 hours post-release. The oil may still be dispersible after 72 hours on the water surface, but the effectiveness of dispersant use would likely be diminished after th e oil has been on the water for more than three days. Ultimat ely, the USCG SMART monitoring protocol will be used to determine whether or not dispersant operations are effective.

d. Once the CGA HOSS barge is on locati on and in the skimming mode, dispersants would only be used if required and approved.

8. Deploy offshore mechanical oil containment and recovery equipment. Attempt to recover as much oil at sea as possible, utilizing:

a. The CGA HOSS barge, will be positioned in a stationary mode, will be situated downwind and down-current from location fo r long-duration, high-volume skimming. Based on average travel times, the HO SS barge could be on location within approximately 31 hours of the release. The de-rated skimming capacity of the HOSS barge is 43,000 bbls per day. However, only the oil encountered by a skimmer can be recovered. In order to maximize oil encount er rate, boom will be deployed in a V-configuration in front of the HOSS barge to funnel oil to the skimmers. If necessary, temporary barges can be ac tivated to support continuous skimming operations. (These barges arrive on-site at approximately the same time as the HOSS barge.) For an on-going release, multiple barges are deployed to provide for continuous off-loading of skimmer storage vess els and shuttling of recovered oil to an onshore waste handling facility. Sufficient barges are available to provide enough temporary storage for continuous recovery operations.

b. CGA’s Fast Response Units (FRU) woul d arrive on-scene between approximately 17-25 hours of the initial release. These sk immers operate downstream of the HOSS barge and are used to recover pockets and streamers of oil that may move past the large stationary skimmer. Each FRU has 200 barrels of on-board storage. Approval will be requested to decant water after gravity separation, through a hose forward of the skimmer, to optimize temporary storage capacity. A 42" Boom will be utilized to concentrate oil so that it is thick enough to be skimmed.

### 9. Dispersants, Fast Response Units (FRU), Oil Spill Response Vessels (OSRV or R/V) would typically work daylight hours onl y. The HOSS barge can operate continuously, including night operations. Available technology will be considered such as remote sensing devices that will enable 24 hour surveillance, trajecto ries, and planning. All response vessels are designed to be able to remain offshore continuously throughout the response. Even if sea conditions prohibit effective skimming, these resources would remain offshore until skimming operations c ould be commenced again. Safety would remain the first priority.

10. Prepare Site-Specific Waste Management Pla n, Site Safety Plan, Decontamination Plans, Communications and Medical Plans.

11. If oil becomes a threat to any shoreline, da ta from the aerial survei llance, weather reports, and trajectories would be used to direct onshore teams to deploy protection/containment boom with reference to Area Contingency Pl ans and in coordination with State and Federal On-Scene Coordinators.

a. Implement pre-designated strategies.

b. Identify resources at risk in spill vicinity.

c. Develop/implement appropriate protection tactics.

12. Establish Site-Specific Wildlif e Rescue and Rehabilitation Plan.

The following types of additional support may be required for a blowout lasting 120 days.

 Additional Oil Spill Remova l Organization (OSRO) personnel to relieve equipment operators

 Vessels for supporting offshore operations

 Field safety personnel

 Continued surveillance and m onitoring of oil movement

 Helicopter, video cameras

 Infra red (night time spill track ing) capabilities, X-band radar

 Barge to transport recovered oil from offshore skimming system, and temporary storage barges to onshore disposal sites th at are identified in Area Contingency Plans (ACP)

 Logistics needed to support equipment:

- Staging areas

- Parts, trailers, and mechanics to maintain skimmers and boom

- Fueling facilities

- Decontamination stations

- Dispersant stockpile tran sported from Houston to Houma or other potential command post locations

- Communications equipm ent and technicians

 Logistics needed to s upport responder personnel

- Medical aid stations- 

### Safety personnel

- Food

- Berthing

- Additional clothing/safety supplies

- Decontamination stations

Louisiana CZM Containment Response Information Anadarko has the capability to respond and cont ain, to the maximum extent practicable as defined in 30 CFR 254.6 and 30 CFR 250.26(d)(1), to the estimated wors t case discharge (WCD) associated with the proposed activity within 30 days. Deployment time for surface containment equipment is subject to availability and loca tion, weather conditions, potential security zones around the spill site, and site/well specific assessment data. Personnel safety is always first and foremost. Refer to further detail s on equipment and timing provided in Section H–Oil Spill Information and Table H-3 of the EP.

The potential WCD will be further evaluated du ring the Application for Permit to Drill (APD) process, including the Well Containment Screen ing Tool (WCST) and associated subsea containment plan for enhanced planning purposes.

There will be no new or unusual technology deployed that has not been previously deployed for Gulf of Mexico oil spill prev ention, control, and/or cleanup.Table H-1

Worst Case Discharge Calculation (Based on Blowout during Drilling Operations)

Calculations for Uncontrolled Blowout> 10 miles from shore: Block 724

i. Type of Oil (crude, condensate, diesel) Crude

ii. API Gravity 30.9 o -32.2 o

iii. EP Location Used for NTL No. 20 10-N06 WCD for GC 724 IEP GC 724 “A”

iv. Largest Anticipated WCD Rate during blowout 201,530 BOPD

v. WCD Total for Drilling Operations for GC 724 (> 10 miles from shore): 201,530 BOPDTable H-2

Trajectory by Land Segment

Following are the average conditional probabilities (expresse d as percent chance) that an oil spill starting at a particular launch area will contact a land segment as included in the BOEMRE Oil Spill Risk Analysis Model (OSRAM) for the Central Gulf of Mexico. This information can be found on the BOEMRE website using 3/10/30 day potential impact, as applicable. The results are listed below.

Area/Block OCS-G Launch Area Land Segment and/or Resource Conditional Probability (%) 3 days 10 days 30 days

Green Canyon

Block 724

Drilling (122miles from shore) G34557 LA 45

Central Planning

Area Calhoun, TX Matagorda County, TX Brazoria County, TX Galveston County, TX Jefferson County, TX Cameron Parish, LA Vermilion Parish, LA Iberia, LA Lafourche Parish, LA Terrebonne Parish, LA Plaquemines Parish, LA --

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-- 1 1 1 2 1 4 2 1 1 2 2Table H-3WCD Scenario Drilling Activities – Based on a singlewell uncontrolled blowout (122 miles from shore)Green Canyon Block 724201,530 BOPD (initial volume)169,285 BOPD (after evaporation/dispersion)API Gravity 30.9o-32.2oOffshore Equipment from Spill Detection to EquipmentDeployment Response Time:Green Canyon Block 724Spill Team Area Responders (STARS) called out by Marine Spill Response Corporation (MSRC)Vessel of Opportunity=VOOEMS=Enterprise Marine ServicesK-Sea=K-Sea Operating PartnershipNearshore Equipment from Spill Detection to Equipment Deployment Response Time: Green Canyon Block 724*Some equipment may be used offshoreup to approximately 25 miles from shoreH-3 (continued)

Operational Limitations of Response Equipment

 HOSS Barge–8 foot seas

 Fast Response Unit (FRU)–8 foot seas

 Oil Spill Response Vessel (OSRV and R/V)–4 foot seas

 Boom–3 foot seas, 20 knot winds

 Dispersants–winds more than 25 knots, visibility less than 3 nautical miles or ceiling less than 1,000 feet

### I Environmental Monitoring and Envi ronmental Mitigation Measures

(a) Monitoring

If required, Anadarko will monitor loop currents per NTL 2005-G05.

Anadarko subscribes to Wilkins Weather Service which provides real-time weather conditions such as tropical depressions, st orms and/or hurricanes entering the Gulf.

(b) Incidental Takes

Although marine mammals may be seen in the area, Anadarko does not believe that its operations proposed under this EP will result in the harassment, capture, collection or killing of any mammals covered by th e Marine Mammal Protection Act.

Anadarko will operate in accordance with applicable regulations, including:

NTL No. 2012-G02 – “Implementation of Se ismic Survey Mitigation Measures and Protected Species Observer Program” BSEE NTL No. 2012-G01 “Marine Trash and De bris Awareness and Elimination”, and JOINT NTL No. 2012-G01 “Vessel Strike A voidance and Injured/Dead Protected Species Reporting”

### J LEASE STIPULATIONS INFORMATION

Lease Sale # 222:

Military Area: Green Canyon Block 724 is loca ted within Military Warning Area W-92. Anadarko will contact the Naval Air Station, Air Operations Department, New Orleans, Louisiana in order to coordi nate and control the electroma gnetic emissions during these proposed operations.

### K Support Vessels and Aircraft Information

(a) General

Type Max. Total Fuel Tank Storage Capacity Max. No. in Area at any Time Trip Frequency or Duration Supply Vessel 336,227 gallons 1 2 trips/week Helicopter 735.3 gallons 1 10 trips/week Crew Vessel 50,000 gallons 1 3 trips/week Tug Boats N/A N/A N/A

(b) Diesel Oil Supply Vessels

Fuel for the rig will be transported via a supply vessel as follows:

a. Size of fuel supply vessel: 230 feet
b. Carrying capacity of fuel supply vessel: 336,227 gallons

c. Frequency that fuel supply vessel will visit the facilities: twice per week

d. Routes the fuel supply vessel will use to travel between the onshore support base and proposed facility: 6 miles from Port Fourchon to the mouth of Bayou Lafourche, then approximately 133 miles to GC 724.

(c) Vicinity Map

A vicinity map is included in this section as Attachment K-1.

(d) Produced Liquid Hydrocarbons Transportation Vessels

Produced liquid hydrocarbons from future flow t ests on wells in Green Canyon Block 724 will be transported by barge. Flow tests will not exceed 48 hours/well without further approval.

Transport Method Vessel Capacity Average Volume to be Loaded (per transfer) No. of Transfers (Yearly Average) Barge 50,000 to 130,000 bbls Proprietary Info 1

(e) Summary of Method to Transfer Liquid Hydrocarbons to the Transporting Vessel

Production from the well will be routed through portable surface well test equipment and safety controls aboard the rig. Gas will be flared and liquids (oil & water) will be collected in US Coast Guard approved tanks and a barge. The well will be produced / cleaned up and measured using various meters through portable surface well test equipment including a separator. A three phase separator will be used to analyze water cut if present. All liquids (hydrocarbons and water) will then be transferred to a coast guard approved barge via tested & approved petroleum transfer hose. We will have a Safe Breakaway Couplin g (KLAW) installed between the hoses connectingthe barge-end and the rig-end. If this device part s the KLAW is designed to contain all fluids from both hoses.

(e) Solid and Liquid Wastes Transportation Type of Waste Composition Total Projected Amount Rate Transport Method Name/Location of Facility Disposal Method

Syntheticbased drilling fluid or mud Syntheticbased drilling muds 30,000 bbls 10,000 bbls/well Re-use and/or transport to shore in DOT approved containers. Waste - Port Fourchon, LA and on to Newpark Fourchon Transfer Station #1 & #2. Newpark Transfer Station Morgan City. Newpark Transfer Station Port Arthur. USLL Galveston and Fourchon Transfer Station. If recycled, returned to vendor (Bariod or MI). Re-used and/or recycled; if can’t be reused and/or recycled the waste is disposed of at Newpark (injection disposal facility) or USLL (landfarm).

Cuttings wetted withsyntheticbased muds Cuttings coated with synthetic drilling muds, including drilled out
cement 300-600 bbls 100-200 bbls/well*

*An estimated 5-10% of cuttings may be transported to shore Re-use and/or transport to shore in DOT approved containers. Waste - Port Fourchon, LA and on to Newpark Fourchon Transfer Station #1 & #2. Newpark Transfer Station Morgan City. Newpark Transfer Station Port Arthur. USLL Galveston and Fourchon Transfer Station. If recycled, returned to vendor (Bariod or MI). Re-used and/or recycled; if can’t be reused and/or recycled the waste is disposed of at Newpark (injection disposal facility) or USLL (landfarm).

Chemical product waste (well
treatment fluids) Ethylene glycol

Methanol 1,500 bbls

375 bbls 100 bbls/month

25 bbls/month Transport to shore in DOT approved containers for pick up Chemwaste in Sulphur, LA and Veolia Port Arthur, TX or to Newpark,Port Arthur as nonhazardous waste. Can be returned to vendor and/or used at another facility; MEG is solidified and disposed of in a landfill. Methanol is incinerated or used for fuels blending. Completion fluids Brine, spent acid, prop sand, debris 9,000 bbls 3,000 bbls/well Transport to shore in DOT approved containers and/or vessel tanks for pick up Sent to Port Fourchon, LA and on to Newpark Fourchon Transfer Station #1 & #2. Newpark Transfer Station Morgan City. Newpark Transfer Station Port Arthur. USLL Galveston and Fourchon Transfer Station Unused brine can be returned to vendor and/or stored for use on another job. Used brine and spent acid is transferred to Newpark's Processing & Transfer facility for injection. Workover fluids Brine, spent acid, prop sand, debris 9,000 bbls 3,000 bbls/well Transport to shore in DOT approved containers and/or vessel tanks for pick up Sent to Port Fourchon, LA and on to Newpark Fourchon Transfer Station #1 & #2. Newpark Transfer Station Morgan City. Newpark Transfer Station Port Arthur. USLL Galveston and Fourchon Transfer Station Unused brine can be returned to vendor and/or stored for use on another job. Used brine and spent acid is transferred to Newpark's Processing & Transfer facility for injection.Trash and debris Refuse generated during operations 750 bbls 50 bbls/month/well Transport to shore in disposal bags by vessel to shorebase for pickup by municipal operations Recycled Material in ARC, New Iberia, LA. Trash disposed of at SWDI landfill. Recycled and/or disposed in landfill.

Used oil Excess oil from engines 1,613 bbls 430 bbls/120 days/well Transport in DOT approved containers to shore for pick up American Recovery Fourchon, LA Recycled

*Total amount assumes drilling & completin g 3 wells with 450 Total No. of DaysGreenCanyonBlocks724and768July2014EnvironmentalImpactAnalysisforInitialExplorationPlanPage2CSA‐Anadarko‐FL‐14‐2716‐01‐REP‐01‐Ver01Figure1.LocationofGreenCanyonBlocks724and768offshoreofthecoastofLouisiana.

### L ONSHORE SUPPORT FACILITIES INFORMATION

(a) General

Per NTL No. 2008-G04, the following tables reflect the onshore facilities Anadarko may utilize to provide supplies and service support for the activities proposed in this EP.

Name Primary Location(s ) Existing/New/Modified Anadarko Service Base Fourchon, Louisiana Existing Anadarko Service Base (Helicopter base) Houma, LA Existing

Name *Alternate Locations Existing/New/Modified Anadarko Service Base Galveston, TX Existing Anadarko Service Base Cameron, LA Existing Anadarko Service Base Lake Charles, LA Existing Anadarko Service Base Houma, LA Existing Anadarko Service Base Pascagoula, MS** Existing *In the unlikely event Anadarko’s primary service base cannot be utilized Anadarko will exercise the use of an alternate service base during drilling and/or completion operations.

**Helicopter base only

(b) Support Base

No support base construction or expans ion is planned for these activities.

(c) Waste Disposal

Disposed wastes describe those wastes generated by the proposed activity that are disposed of by means other than by release into the water of th e GOM at the site where they are generated. These wastes can be disposed of by offsite release, injection, encapsulation, or placement at either onshore or offshore permitted locations for th e purposes of returning them back to the environment.

Type of Waste Composition Total Projected Amount Rate Transport Method Name/Location of Facility Disposal Method

Syntheticbased drilling fluid or mud Syntheticbased drilling muds 30,000 bbls 10,000 bbls/well Re-use and/or transport to shore in DOT approved containers. Waste - Port Fourchon, LA and on to Newpark Fourchon Transfer Station #1 & #2. Newpark Transfer Station Morgan City. Newpark Transfer Station Port Arthur. USLL Galveston and Fourchon Transfer Station. If recycled, returned to vendor (Bariod or MI). Re-used and/or recycled; if can’t be reused and/or recycled the waste is disposed of at Newpark (injection disposal facility) or USLL (landfarm).Cuttings wetted withsyntheticbased muds Cuttings coated with synthetic drilling muds, including drilled out
cement 300-600 bbls 100-200 bbls/well*

*An estimated 5-10% of cuttings may be transported to shore Re-use and/or transport to shore in DOT approved containers. Waste - Port Fourchon, LA and on to Newpark Fourchon Transfer Station #1 & #2. Newpark Transfer Station Morgan City. Newpark Transfer Station Port Arthur. USLL Galveston and Fourchon Transfer Station. If recycled, returned to vendor (Bariod or MI). Re-used and/or recycled; if can’t be reused and/or recycled the waste is disposed of at Newpark (injection disposal facility) or USLL (landfarm).

Chemical product waste (well
treatment fluids) Ethylene glycol

Methanol 1,500 bbls

375 bbls 100 bbls/month

25 bbls/month Transport to shore in DOT approved containers for pick up Chemwaste in Sulphur, LA and Veolia Port Arthur, TX or to Newpark,Port Arthur as nonhazardous waste. Can be returned to vendor and/or used at another facility; MEG is solidified and disposed of in a landfill. Methanol is incinerated or used for fuels blending.

Completion fluids Brine, spent acid, prop sand, debris 9,000 bbls 3,000 bbls/well Transport to shore in DOT approved containers and/or vessel tanks for pick up Sent to Port Fourchon, LA and on to Newpark Fourchon Transfer Station #1 & #2. Newpark Transfer Station Morgan City. Newpark Transfer Station Port Arthur. USLL Galveston and Fourchon Transfer Station Unused brine can be returned to vendor and/or stored for use on another job. Used brine and spent acid is transferred to Newpark's Processing & Transfer facility for injection. Workover fluids Brine, spent acid, prop sand, debris 9,000 bbls 3,000 bbls/well Transport to shore in DOT approved containers and/or vessel tanks for pick up Sent to Port Fourchon, LA and on to Newpark Fourchon Transfer Station #1 & #2. Newpark Transfer Station Morgan City. Newpark Transfer Station Port Arthur. USLL Galveston and Fourchon Transfer Station Unused brine can be returned to vendor and/or stored for use on another job. Used brine and spent acid is transferred to Newpark's Processing & Transfer facility for injection. Trash and debris Refuse generated during operations 750 bbls 50 bbls/month/well Transport to shore in disposal bags by vessel to shorebase for pickup by municipal operations Recycled Material in ARC, New Iberia, LA. Trash disposed of at SWDI landfill. Recycled and/or disposed in landfill.

Used oil Excess oil from engines 1,613 bbls 430 bbls/120 days/well Transport in DOT approved containers to shore for pick up American Recovery Fourchon, LA Recycled

*Total amount assumes drilling & completin g 3 wells with 450 Total No. of Days

### M COASTAL ZONE MANAGEM ENT ACT INFORMATION

### TEXAS COASTAL MANAGEMENT PROGRAM

The following is an evaluation that includes findi ngs relating the coastal effects of the proposed activities and associated facilities to the relevant enforceable policies of the Texas’ Coastal Management Program (TCMP), Title 31, Part 16, Chapter 501, Subchapter B :
(Category 2) Construction, Operation & Maintenance of Oil & Gas Exploration & Production Facilities

No operations are proposed in or near any critical areas. The proposed activities are explorative in nature, so no facility construction is proposed. Th e proposed activities are located approximately 235 miles from the Texas shoreline; therefore we expect no adverse impacts to CNRAs or beach access and use rights of the public. All activities sh all be conducted in a manner that minimizes significant impacts to coastal resources. No adverse effects to Texas’ coastal area are expected in association with the proposed activities.

(Category 3) Discharges of Wastewater and Disposal of Waste from Oil and Gas Exploration and Production Activities

No discharge of wastewater or disposal of waste from the proposed activities will occur in the Texas’ coastal zone; therefore no impact to Texas’ coastal waters is expected.

(Category 4) Construction and Operation of Solid Waste Treatment, Storage, and Disposal Facilities

No construction of solid waste facilities or expans ion of existing facilities in the coastal zone are proposed in the attached plan, therefore, no adver se effects on any features of Texas’ coastal cone are expected.

(Category 5) Prevention, Response, and Remediation of Oil Spills

The proposed activities will be covered under an approved Regional Oil Spill Response Plan. The plan is in place, practiced, and updated as n ecessary. The best practical techniques shall be utilized to prevent the release of pollutants or t oxic substances into the environment. All involved vessels and facilities are designed to be capable of prompt response and adequate removal of accidental discharges of oil. In addition, th e proposed activities are 235 miles from shore; therefore no damages to natural resources are exp ected as the result of an unauthorized discharge of oil into coastal waters.

(Category 6) Discharge of Municipal and Industria l Waste Water to Coastal Waters

No discharges from the proposed activities will o ccur in coastal waters. The proposed activities are 235 miles from shore; therefore there will be no effect on coastal waters.(Category 8) Development in Critical Areas

None of the proposed activities will occur in a criti cal area; therefore no effects to Texas’ coastal zone are expected. The activity will not jeopardi ze the continued existence of species listed as endangered or threatened, and will not result in likelihood of the destruction or adverse modification of a habitat determined to be a critical habitat under the Endangered Species Act. The activity will not cause or contribute to vi olation of any applicable surface water quality standards. The activity will not violate any requirement imposed to protect a marine sanctuary.

(Category 9) Construction of Waterfront Facilities and Other Structures on Submerged lands

No waterfront facilities or other structures are pr oposed on submerged lands in the Texas coastal zone, therefore the proposed activities are not expected to have any adverse impacts on submerged lands.

(Category 10) Dredging and Dredged Material Disposal and Placement

No dredging or disposal/placement of dredged ma terial is proposed; therefore no adverse effects to coastal waters, submerged lands, critical area s, coastal shore areas, or Gulf beaches are expected.

(Category 11) Construction in the Beach / Dune System

The proposed activities do not include any construction projects in critical dune areas or areas adjacent to or on Gulf beaches, therefore, no im pact to Texas’ beach or dune systems are expected.

(Category 15) Alteration of Coastal Historic Areas

The proposed activities do not include any alteration or disturbance of a coastal historic area; therefore, no impacts are expected to adversely affect any historical, architectural, or archaeological site in Texas’ coastal zone.

(Category 16) Transportation

The proposed activities do not include any transpor tation construction projects within the coastal zone; therefore, no impacts to Texas’ coastal zone are expected.

(Category 17) Emission of Air Pollutants

The proposed activities shall be carried out in conformance with applicable air quality laws, standards, and regulations. Emissions from th e proposed activities are not expected to have significant impacts on onshore air quality becau se of the prevailing atmospheric conditions, emission heights, emission rates, and the dist ance of these emissions from the coastline. Theproposed activities will occur approximately 2 35 miles from shore and will be within the exemption limits set by BOEM, therefore, no im pacts to Texas’ coastal zone is expected.

(Category 18) Appropriations of Water

The proposed activities do not include the impoundment or diversion of state water, therefore, no impacts to Texas’ coastal zone is expected.

(Category 20) Marine Fishery Management

The proposed activities are located approximately 235 miles from shore and are not expected to have any effect on marine fishery management or fishery migratory patterns within waters in the coastal zone of Texas.

(Category 22) Administrative Policies

The necessary information for app licable agencies to make an informed decision on the proposed activities has been provided In conclusion, all activ ities shall be consistent with Texas’ coastal management program and shall comply with all relevant rules and regulations. No activities are planned within any critical areas. Activities will be carried out avoiding unnecessary conflicts with other uses of the vicinity.

### MISSISSIPPI COASTAL ZONE M ANAGEMENT ACT INFORMATION

As authorized by the Federal Coastal Zone Management Act (CZMA), The State of Mississippi developed a Coastal Management Pr ogram (CMP) to allow for the review of proposed Federal license and perm it activities affecting any coasta l use or resources, in or outside of the Missi ssippi Coastal Zone.

The OCS related oil and gas exploratory a nd development activities having potential impact on the Mississippi Coastal Zone are based on the location of the proposed facilities, access to those sites, best practic al techniques for drilling locations, drilling equipment guidelines for the prevention of adverse environmental effects, effective environmental protection, emergenc y plans and contingency plans.

Below are goals identified by the State of Mississippi and our comments and/or corresponding cross references:

Goal 1: To provide for reaso nable industrial expansion in the coastal area and to ensure the efficient utilization of waterfront industrial sites so that suitable sites are conserved for water dependent industry.

The activities proposed in this plan are base d out of Fourchon, Louisi ana. The activities will not provide any industrial expansion on the coastal area of Mississippi. Therefore Mississippi coastal areas will be cons erved for water dependent industry.

Goal 2: To favor the preservation of the coastal wetlands and ecosystems, except where a specific alteration of specific coasta l wetlands would serve a higher public interest in compliance with the public pur poses of the public trust in which the coastal wetlands are held.

Goal 2 is addressed in Section N, Environm ental Impact Analysis. The nearest proposed activities will be 200 miles fr om the Mississippi coast.

Goal 3: To protect, propagate and conserve the state’s seafood and aquatic life in connection with the revitalization of the se afood industry of the State of Mississippi.

Goal 3 is addressed in Section N, Environm ental Impact Analysis. Little impact to the seafood industry can be expected due to th e activities occurring 200 miles from the Mississippi coast.

Goal 4: To conserve the air and waters of the state, and to protect, maintain and improve the quality thereof for public use, fo r the propagation of wildlife, fish and aquatic life, and for domestic, agricultu ral, industrial, recreational and other legitimate beneficial uses.

Goal 4 is addressed in Section B, Gene ral Information, Sectio n G, Air Emissions Information, and Section N, Environmental Impact Analysis.

### Goal 5: To put to be neficial use to the fullest extent of which they are capable the water resources of the state, and to prev ent the waste, unreasonable use, or unreasonable method of use of water.

The activities proposed in this plan are based in Fourchon, Louisiana. As such, Mississippi’s water resources should not be impacted by the proposed activities. Activities occurring at the sites in the OC S will be conducted in accordance with our Regional Oil Spill Response Plan refere nced in Section H of this plan.

Goal 6: To preserve the stat e’s historical and archaeological resources, to prevent their destruction, and to enhance these resources wherever possible.

Goal 6 is addressed in Section E, Biologica l, Physical and Socioeconomic Information, and Section N, Environmental Impact Analysis.

Goal 7: To encourage the preservation of na tural scenic qualities in the coastal area.

Goal 7 is addressed in Section F, Waste Discharges Information, Section H, Oil Spill Information, Section G, Air Emissions In formation, and Section N, Environmental Impact Analysis.

Goal 8: To assist local governments in the pr ovision of public facilities services in a manner consistent with the coastal program.

As the proposed activities ar e located 200 miles from the Mi ssissippi coast and are based out of a shorebase in Fourchon, Louisiana, local governments should not be affected.

### N ENVIRONMENTAL IMPACT ANALYSIS

# Environmental Impact Analysis

INITIAL EXPLORATION PLAN

for

Green Canyo n Blocks 724 and 768 ( OCS

- G 21814 and OCS

- G 21817)

Offshore Louisiana

July 2014

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### Prepared for:

Jill Fowler Regulatory Analyst Anadarko Petroleum Corporation 1201 Lake Robbins Drive The Woodlands, Texas 77380

Telephone: (832) 636

- 1554



### Prepared by:

CSA Ocean Sciences Inc. 8502 SW Kansas Avenue

Stuart, Florida 34997 Telephone: (772) 219

- 3000

## ENVIRONMENTAL IMPACT ANALYSIS INITIAL EXPLORATION PLAN FOR GREEN CANYON BLOCKS 724 AND 768 (OCS

- G 21814 AND OCS

- G 21817) OFFSHORE LOUISIANA

DOCUMENT NO. CSA

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V ERSION D ATE D ESCRIPTION P REPARED B Y : R EVIEWED B Y : A PPROVED B Y :

01 7/3/14 Initial draft for review MJT JH, NK, LR MJT

FIN 7/9/14 Final MJT NK MJT

Next Review Due Date: Next Review By:

The electronic PDF version of this document is the Controlled Master Copy at all times. A printed copy is considered to be uncontrolled and it is the holder’s responsibility to ensure that they have the current revision. Controlled copies are available on the Management System network site or on request from the Document Production team.

## Contents

Page



### List of Tables

................................ ................................ ................................ ................ v List of Figures

................................ ................................ ................................ ............... v Acronyms and Abbreviations

................................ ................................ ...................... v i

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

................................ ................................ ................................ ................. 9 A.7 Marine Debris

................................ ................................ ................................ ................................ . 9 A.8 Support Vessel and Helicopter Traffic

................................ ................................ ............................ 9 A.9 Accidents

................................ ................................ ................................ ................................ ...... 10 A.9.1 Types of Accidents Evaluated

................................ ................................ ........................... 10 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

................................ ................................ ............ 15



### B. Affected Environment

................................ ................................ ........................... 17
C. Impact Analysis

................................ ................................ ................................ ..... 19
C.1 Physical/Chemical Environment

................................ ................................ ................................ ... 19 C.1.1 Air Quality

................................ ................................ ................................ ......................... 19 C.1.2 Water Quality

................................ ................................ ................................ .................... 21 C.2 Seafloor Habitats and Biota

................................ ................................ ................................ .......... 23 C.2.1 Soft Bottom Benthic Communities

................................ ................................ ................... 23 C.2.2 High

- Density Deepwater Benthic Communities

................................ ............................... 26 C.2.3 Designated Topographic Features

................................ ................................ .................... 28 C.2.4 Pinnacle Trend Area Live Bottoms

................................ ................................ .................... 28 C.2.5 Eastern Gulf Live Bottoms

................................ ................................ ................................ . 28 C.3 Threatened, Endangered, and Protected Species and Critical Habitat

................................ ........ 29 C.3.1 Sperm Whale (Endangered)

................................ ................................ .............................. 31 C.3.2 West Indian Manatee (Endangered)

................................ ................................ ................. 35 C.3.3 Endangered Mysticete Whales

................................ ................................ ......................... 36 C.3.4 Non

- Endangered Marine Mammals (Protected)

................................ .............................. 36 C.3.5 Sea Turtles (Endangered/Threatened)

................................ ................................ ............. 40 C.3.6 Piping Plover (Threatened)

................................ ................................ ............................... 43 C.3.7 Whooping Crane (Threatened)

................................ ................................ ......................... 44 C.3.8 Gulf Sturgeon (Threatened)

................................ ................................ .............................. 46

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## Contents (Continued)

Page

C.3.9 Beach Mice (Endangered)

................................ ................................ ................................ . 47 C.3.10 Smalltooth Sawfish (Endangered)

................................ ................................ ..................... 47 C.3.11 Elkhorn Coral (Threatened)

................................ ................................ ............................... 48 C.4 Coastal and Marine Birds

................................ ................................ ................................ .............. 49 C.4.1 Marine Birds

................................ ................................ ................................ ...................... 49 C.4.2 Shorebirds and Coastal Nesting Birds

................................ ................................ ............... 51 C.5 Fisheries Resources

................................ ................................ ................................ ...................... 53 C.5.1 Pelagic Communities and Ichthyoplankton

................................ ................................ ...... 53 C.5.2 Essential Fish Habitat

................................ ................................ ................................ ........ 55 C.6 Archaeological Resources

................................ ................................ ................................ ............. 58 C.6.1 Shipwreck Sites

................................ ................................ ................................ ................. 58 C.6.2 Prehistoric Archaeological Sites

................................ ................................ ........................ 59 C.7 Coastal Habitats and Protected Areas

................................ ................................ .......................... 60 C.8 Socioeconomic and Other Resources

................................ ................................ ........................... 62 C.8.1 Recreational and Commercial Fishing

................................ ................................ .............. 62 C.8.2 Public Health and Safety

................................ ................................ ................................ ... 64 C.8.3 Employment and Infrastruc ture

................................ ................................ ....................... 65 C.8.4 Recreation and Tourism

................................ ................................ ................................ .... 66 C.8.5 Land Use

................................ ................................ ................................ ............................ 67 C.8.6 Other Marine Uses

................................ ................................ ................................ ............ 67



### D. Environmental Hazards

................................ ................................ ......................... 68
D.1 Geologic Hazards

................................ ................................ ................................ .......................... 68 D.2 Severe Weather

................................ ................................ ................................ ............................ 68 D.3 Currents and Waves

................................ ................................ ................................ ..................... 68



### E. Alternatives

................................ ................................ ................................ .......... 69

F. Mitigation Measures

................................ ................................ ............................. 69

G. Consultation

................................ ................................ ................................ ......... 69

H. Preparers

................................ ................................ ................................ .............. 69

I. References

................................ ................................ ................................ ............. 69

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## List of Tables

Table Page

1 Notices to Lessees and Operators (NTLs) applicable to this Envi ronmental Impact Analysis (EIA)

................................ ................................ ................................ ........................... 3

2 Matrix of impact

- producing fact ors and environmental resources

................................ ....... 6

3 Conditional probabilities of a spill in the lease area contacting shoreline segments based on the 30

- day Oil Spill Risk Analysis (OSRA) (From: Ji et al., 2004)

............................ 12

4 Conditional probabilities of a spill in the lease area contacting shoreline segments based on the 120

- day Oil Spill Risk Analysis (OSRA)

................................ ............................. 13

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 (Adapted from: Wei, 2006; Rowe and Kennicutt, 2009)

........... 24

6 Federally listed endangered and threatened species that could potentially occur in the lease area an d along the northern Gulf Coast

................................ ............................... 30

7 W ildlife refuges, wilderness areas, and state and national parks within the geographic range of the potential shoreline contacts after 30 days based on OSRA modeling

................................ ................................ ................................ ............................... 61



## List of Figures

Figure Page

1 Location of Green Canyon Blocks 724 and 768 off shore of the coast of Louisiana

............... 2

2 Bathymetric map of the lease area showing the surface hole loca tions of the proposed wellsites

................................ ................................ ................................ ................ 18

3 Location of selected environmental features in relation to the lease areas of interest

................................ ................................ ................................ ................................ .. 45

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## Acronyms and Abbreviations

ac acre ADIOS 2 Automated Data Inquiry for Oil Spills 2 Anadark o Anadarko Petroleum Corporatio n bbl barrel
BHL bottom hole location BOEM Bureau of Ocean Energy Management BOEMRE Bureau of Ocean Energy Managem ent, Regulation and Enf orcement BOP blowout preventer
B.P. b efore p resent BSEE Bureau of Safety and Environmental Enforcement CFR Code of Federal Regulations CH 4 methane CO carbon monoxide CO 2 carbon dioxide CGA Clean Gulf Associates
DP dynamic ally position ed DPS distinct population s egment 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 aggregating device
FR Federal Register GC Green Canyon GM FMC Gulf of Mexico Fishery Management Council GPS g lobal p ositioning s ystem H 2 S hydrogen sulfide ha hectare HAPC Habitat Area of Particular Concern HOSS high

- volume open sea skimmer
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 MSRC Marine Spill Response Corporation MWCC Marine Well Containment Company NAAQS National Ambient Air Quality Standards NMFS National Marine Fisheries Service NMS National Marine Sanctuary NOAA National Oceanic and Atmospheric Administration NO 2 nitrogen dioxide NO x nitrogen oxides NPDES National Pollutant Discharge Elimination System NPS National Park Service
NRDA Natural Resource Damage Assessment NTL Notice to Lessees and Operators
NWR National Wildlife Refuge OCS Outer Continental Shelf OSAT Operational Scientific Advisory Team OSRA Oil Spill Risk Analysis OSRP Oil Spill Response Plan
PAH polycyclic aromatic hydrocarbon
PM particulate matter PSD Prevention of Significant Deterioration SBM synthetic

- based mud SHL surface hole location SO x 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 WCEP Whooping Crane Eastern Partnership

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## Introduction

Anadarko Petroleum Corporation ( Anadarko ) is submitting a n Initial E xploration Plan (EP) for Green C anyon ( G C) Blocks 724 ( G C 724 ) and 768 ( G C 768 )

. Under the EP, Anadarko proposes to drill and complete three wells: GC 724 A, GC 724 AA, and GC 724 AAA . All wells will have their surface hole locatio n s (SHL s ) in GC 768 and bottom hole location s (BHL s ) in GC 724

. This Environmental Impact Analysis (EIA) provides information on potential impacts of Anadarko’s proposed activities based on the SHLs

.
The lease area is 122 miles ( 196 km ) from the nearest shoreline
, 135 miles ( 217 km ) from the onshore support base at Port Fourchon, Louisiana, and 160 miles ( 258 km ) from the helicopter base at Houma, Louisiana ( Figure 1 ). Water depth s at the wellsites are between 1,573 and
1
, 695 m ( 5,160 to 5,560 ft )

. The drilling rig has not yet been determined but will be a dynamic ally positioned (DP) drillship or semisubmersible rig. It is anticipated that drilling operations for t he exploratory wells covered in the EP will require 150 days for completion , but a firm schedule as not yet been established

.
This EIA was prepared for submittal to the Bureau of Ocean Energy Management (BOEM) in accordance with applicable regulations, including 30 Code of Federal Regulations (CFR) 550.212(o) and 550.227

. Th is EIA is a project

- and site

- specific analysis of Anadarko ’s p lanned activities under th e EP. This EIA complies with guidance provided in existing Notices to Lessees and Operators (NTLs) issued by the former Minerals Management Service (MMS) and Bureau of Ocean Energy Management, Regulation and Enforcement ( BOEMRE )

, including NTL s 2008

- G04 and 201 4

- G03

. 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; BOEM

, 2012 a ) and in multi

- lease

- sale EISs for the Western and Central Gulf of Mexico Planning Areas (MMS, 2007b; BOEM, 2012b

, c, 2013 ). The analyses from th o se documents are incorporated here by reference.

All the proposed activities and facilities discussed in th e EP are cov ered by the Sub

- Regional Oil Spill Response Plan (OSRP) last approved on 15 April 2013 for Anadarko and its subsidiaries, Anadarko U

. S

. Offshore Corporation and Anadarko E&P Compa ny L.P. (Company Numbers 00981, 02219
, and 00148, respectively)

, in accordanc e with 30 CFR Part 254.

The OSRP details Anadarko’s plan to rapidly and effectively manage oil spills that may result from drilling and production operations. Anadarko has designed its spill response program based on a regional capability of respon se to spill s ranging from small operational spills to a worst case discharge (WCD) from a well blowout. Anadarko’s spill response program meets the response planning requirements of the relevant coastal states and applicable F ederal oil spill planning regul ations

. The OSRP also includes information regarding Anadarko’s regional oil spill organization and dedicated response assets, potential spill risks, and local environmental sensitivities. It descri bes personnel and equipment mobilization, incident manag ement team organization, and an overview of actions and notifications to be taken in the event of a spill.

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- FINFigure 1. Location of Green Canyon Blocks 724 and 768 offshore of the coast of Louisiana

.

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- FINTh is EIA is organized into Sections A through I corresponding to the information required by
NTL 2008

- G04. The main impact

- related discussions are in Section A (Impact

- Producing Factors) and Section C (Impact Analysis). Table 1 lists and summarizes the NTLs applicable to this EIA.

Table 1. Notices to Lessees and Operators (NTLs) applicable to this Environmental Impact Analysis ( EIA )

.
NTL Title Summary

2014

- G04 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.

BOEM

- 2014

- G03 Extension of Prior Notices to Lessees Extends the effective date of NTLs 2008

- G04 and 2008

- G05 until 30 June 2014.

BSEE

- 2012

- N06 Guidance to Owners and Operators of Offshore Facilities Seaward of the Coast Line Concerning Regional Oil Spill Response Plans Provides clarification, guidance, and information for preparation of regional Oil Spill Response Plans. Recommends description of response strategy for worst case discharge scenarios to ensure capability to respond to oil spills is both efficient and effective.

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 training and certification process for marine trash and debris

awareness.

2012

- JOINT

- G01 Vessel Strike Avoidance and Injured/Dead Protected Species Reporting Recommends protected species identification guides be carried on all Gulf of Mexico petroleum vessels and that vessel operators and crews maintain a vigilant watch for marine mammals.
V essels are to slow down or stop to avoid striking protected species, and operators are required to report sightings of any injured or dead protected species.

2011

- JOINT

- G01 Revisions to the List of Outer Continental Shelf ( OCS ) Blocks Requiring Archaeological Resource Surveys and Reports Provides new information of which OCS blocks require archaeological surveys and reports ; identifies required survey line spacing in each block. This NTL augments NTL 2005

- G07.

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- FINTable 1. (Continued).

NTL Title Summary

2010

- N10 Stateme nt 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 application s 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 Federal Regist er [ FR ] 63346). Informs operators that the Bureau of Ocean Energy Management 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 blow out 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 WCD scenario and provides guidance regarding the information required in blowout scenario and WCD scenario descriptions.

2009

- G40 Deepwater Benthic Communities Provides guidance f or avoiding and protecting high

- density deepwater benth ic 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 discharg e location and 76 m (250 ft) from all other seafloor disturbances.

2009

- G39 Biologically Sensitive Underwater Features and Areas Provides guidance for avoiding and protecting biologically sens itive features and areas (i.e., topographic features, pinnacles , low relief live bottom areas, and other potentially sensitive biologica l features) when conducting OCS operations in water depths less than 300 m (984 ft) in the Gulf of Mexico.

2008

- G04 Information Requirements for Exploration Plans and Development Operations Coordination Documents Provides guidance on 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. 1

2005

- G07 Ar chaeological 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

.

1 NTL ex tended on 30 June 2014 until 31 December 2014

.

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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 BOEM

- 0 142. An " X " indicates that an IPF could reasonably be expected to affect a certain resource, and a das h (

-- ) 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 sections.

• 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

• Accidents



## A. 1 Drilling Rig Presence ( Including Noise and L ights)

The wells proposed in this EP will be drilled using either a DP drillship or a DP semisubmersible rig. DP drilling rig s use a g lobal p ositioning s ystem (GPS), specific computer software, and sensors in conjunction with their ow n propellers and thrusters to maintain position. T he precise location of the vessel is monitored by vessel operators using satellite navigation. T hrusters positioned at various locations around the vessel’s hull are activated as needed to maintain positi on. This process, known as station

- keeping, allows operations at sea in locations at which mooring or anchoring is impractical or not feasible.

The drilling rig for the three well s proposed in th e EP will be on site for an estimated 150 days per well , but a firm schedule h as not yet been established

. 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 DP drilling vessels is not particularly intense and is strongest at low frequencies, ave raging 10 to 500 Hz (Richardson et al., 1995). From a drilling rig , sound and vibration paths to the water flow 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 Physic al Disturbance to the Seafloor

In water depths of 600 m (1,969 ft) or greater, DP drilling vessels disturb a 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 0.25 h ect a re s (ha) , or approximately 0.62 acre s ( ac) (MMS, 2007a).

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- FINTable 2. Matrix of impact

- producing factors and environmental resources

.

Environmental Resources Impact

- P roducing Factors Drilling Rig Presence (incl. noise & lights) Physical Disturbance to Seafloor Air Pollutant Emissions Effluent Discharges Water Intake Onshore Waste Disposal Marine Debris Support Vessel/Helo

Traffic Accidents Small Fuel Spill Oil Spill (WCD) Physical/Chemical Environment Air quality and greenhouse gases

-- -- X ( 9 )

-- -- -- -- -- X (6) X (6) Water quality

-- -- -- X

-- -- -- -- X (6) X (6) Seafloor Habitats and Biota Soft bottom benthic communities

-- X

-- X

-- -- -- -- -- X (6) High

- density deepwater benthic communities

-- -- (4 )

-- -- (4 )

-- -- -- -- -- X (6) 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) X (6,8) X (6,8) West Indian manatee (endangered)

-- -- -- -- -- -- -- X (8)

-- X (6,8) Endangered mysticete whale s

-- -- - - -- -- -- -- -- -- -- Non

- endangered marine mammals (protected) X

-- -- -- -- -- -- X X (6) X (6) Sea turtles (endangered/threatened) X (8)

-- -- -- -- -- -- X (8) X (6,8) X (6,8) Piping Plover (threatened)

-- -- -- -- -- -- -- -- -- X (6) Whooping Crane (endangered)

-- -- -- -- -- -- -- -- -- X (6) Gulf sturgeon (threatened)

-- -- -- -- -- -- -- -- -- X (6) Smalltooth sawfish (endangered) X (6) Beach m ouse (endangered)

-- -- -- -- -- -- -- -- -- X (6) Elkhorn coral ( threatened )

-- -- -- -- -- -- -- -- -- X (6) Coastal and Marine Birds

Marine birds X

-- -- -- -- -- -- X X (6) X (6) Shorebird s and coastal nesting birds

-- -- -- -- -- -- -- X

-- X (6) Fisheries Resources Pelagic communities and ichthyoplankton X

-- -- X X

-- -- -- X (6) X (6) Essential Fish Habitat X

-- -- X X

-- -- -- X (6) X (6) Archaeological Resources Shipwreck sites

-- -- (7)

-- -- -- -- -- -- -- X (6) Prehistoric archaeological sites

-- -- (7)

-- -- -- -- -- -- -- X (6) Coastal Habitats and Protected Areas

Beaches

-- -- -- -- -- -- -- -- -- X (6) Wetlands and seagrass beds

-- -- -- -- -- -- -- -- -- X (6) Coastal wildlife refuges and wilderness areas

-- -- -- -- -- -- -- -- -- X (6) Socioeconomic and Other Resources

Recreational and commercial fishing X

-- -- -- -- -- -- - - X (6) X (6) Public health and safety

-- -- -- -- -- -- -- -- -- X (6) Employment and infrastructure

-- -- -- -- -- -- -- -- -- X (6) Recreation and tourism

-- -- -- -- -- -- -- -- -- X (6) Land use

-- -- -- -- -- -- -- -- -- X (6) Other marine uses

-- -- -- -- -- -- -- -- -- X (6)

X indicates potential impact; dash (

-- ) indicates no impact or negligible impact ; numbers refer to table footnotes; Helo = helicopter; WCD = worst case discharge. Green Canyon Blocks 724 and 768 July 2014 Environmental Impact Analysis for Initial Exploration Plan Page 6 CSA

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- FINTable 2 Footnotes and Applicability to this Drilling Program : Footnotes are numbered to correspond to entries in Table 2 ; applicability to this case is noted by a bullet point following the footnote. (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 le zone of the Flower Garden Banks or the 3

- mi le zone of Stetson Bank; (b) 1,000

- m, 1

- mi le , or 3

- mi le 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 sanctu ary, 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 Bo ttom (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

- Rel ief) Stipul ation 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 4 00 m or greater.

• No impacts on high

- density deepwater benthic communities are anticipated. There are no features indicative of high

- density chemosynthetic communities or coral communities within 610 m (2,000 ft) of any drilling mud/cuttings discharge location ( Fugro GeoServices, Inc.
, 2003 )

. (5) Exploration or production activities where hydrogen sulfide ( H 2 S ) concentrations greater than 500 parts per million ( ppm ) might be encountered.

• Anadarko is requesting Green Canyon Blocks 724 and 768 be classified as a zone in which the absence of
H 2 S has been confirmed. (6) All activities that could result in an accidental spill of produced liquid hydrocarbons or diesel fuel that would potentially impact these environmental res o urces. If the proposed action is located a sufficient distance from a

resourc e 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 potential impacts are analyzed in Section C

. (7) All activities that involve seafloor disturban ces, 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 pla nned 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 l ease area is not list ed in BOEM’s (2012d)
A rchaeology S urvey B locks

. The lease area is well beyond the 60

- m depth contour used by BOEM as the seaward extent for prehistoric archaeological site potential in the Gulf of Mexico. No archaeological resources were detected in the project area during the archaeological survey s (Fugro GeoServices, Inc.
, 2003 ). A dynamically positioned drilling vessel or semisubmersible rig will be used; therefore, seafloor disturbances due to anchorin g will not occur. (8) All activities that you determine might have an adv erse effect on endangered or threatened marine mammals or sea turtles or their critical ha bitats.

• IPFs that may affect marine mammals, sea turtles, or their critical habitats include drilling rig presence, support vessel and helicopter traffic, and accidents. See Section C

. (9) Production activities that involve transportation of produced fluids to shore using shu ttle tankers or barges.

• Not applicable.

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## A. 3 Air Pollutant Emissions

Air pollutant emissions are calculated in EP Section G and are estimated to be insignificant. Offshore air pollutant emissions will result from drilling rig operations as well as service vessels and helicopters. These emissions occur mainly from combusti on of diesel fuel. The combustion of fuels occurs i n 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 (SO x ), nit rogen oxides (NO x ), 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 regul ations in 30 CFR 550 .303 . Based on this and the distance from 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 EP Section F

. All offshore discharges will be in accordance with requirements of the National Pollutant Discharge Elimination System (NPDES) General Permit No. G M G 29 0000 issued by the U.S. Environmental Protection Agency ( USEPA )

. Any d ischarges 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 t he seafloor during initial well

- dr illing intervals in which the marine riser that enables the return of muds and cuttings to the surface vessel has not been set. Excess cement slurry also will 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 after riser emplacement and either reused by the vendor or transported to Port Fourchon , Louisiana
, for recycling and disposal at an approved facility. Cuttings wetted with SB Ms will be discharged to the seafloor in accordance with the NPDES permit.

Other effluent s that will be discharge d in accordance with the NPDES permit will include excess cement, n on

- contact cooling water, treated sanitary and domestic wastes, deck drainag e, desalination unit brine, uncontaminated freshwater 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. The current NPDES General P ermit No. GMG 290000 does not specify requirements for existing facilities (those that started construction before 16 July 2006)

. The drilling vessel ultimately selected for this project wil l be in compliance with all cooling water intake structure requirements.

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## A. 6 Onshore Waste Disposal

Wastes generated during drilling are tabulated in EP Section F. A total of a pproximately 750 barrels ( bbl ) of trash will be generated over the life of th e project. Trash will be transported to shore in disposal bags for final disposal by municipal operators in accordance with applicable regulations

.


## A. 7 Marine Debris

Anadarko will comply with all regulations relating to solid wastes handling and disposal, including the International Convention for the Prevention of Pollution from Ships (MARPOL 73/78) Annex V requirements and USEPA
, U.S. Coast Guard ( USCG )

, and BOEM regulations

. For example, BOEM regulations 30 CFR 250.300(a) and (b)(6) prohibit operators f rom 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
, containers (especially drums), and other material. The USEPA and USCG regulations require operators to be 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
, the Bureau of Safety and Environmental Enforcement ( 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 training and certification process for marine trash and debris awareness.



## A. 8 Support Vessel and Helicopter Traffic

Anadarko will use existing shorebase facilities at Port Fourchon, Louisiana
, for onshore support for vessel activities. Air transportation (helicopters) will be based at facilities in Houma, Louisiana

. N o terminal ex pansion or construction is planned at either location

. The project will be supported by one crew vessel and one s upply vessel

. The crew vessel will make three round

- trips per week and t he supply vessel will make two round

- trips per week between Port Fourchon and the drilling rig

. The boats typically will move to the project area via the most direct route from the shorebase.

A helicopter will make an estimated 10 round

- trips per week between the drilling rig and the heliport in Houma

. The helicopter will be used to transport personnel as well as small supplies and will normally take the most direct route of travel between the heliport and the lease area when air traffic and weather conditions permit. Helicopters typically maint ain a mi nimum 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. Additional guidelines and regulations specify that helicopters maintain an altitude of 305 m ( 1,000 ft) within 91 m ( 300 ft) of marine mammals (BOEM, 2012a ).

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## A. 9 Accidents

A. 9.1 Types of Accidents Evaluated

The analysis in this EIA focuses on two potential accidents:

• a small fu el spill, which is the most likely type of spill during OCS exploration activities; and

• a large oil spill, up to and including t he WCD for this EP, which is an oil spill resulting from an uncontrolled blowout.

The following subsections summarize assumption s about the size s and fate s of these spills, as well as Anadarko’ s spill response plans. Impacts are analyzed in Section C

.

MMS ( 2007b) and BOEM (2012 a,b , 2013 ) analyze d three other types of accidents: chemical spills, vessel collisions, and loss of well control. These types of accidents are discussed briefly in Section A.9.4

.



### A. 9.2 Small Fuel Spill

Spill Size . According to the analys e s in MMS (2007b ) and BOEM (201 2 a ), the most likely type of small spill (<1,000 bbl) result ing from OCS activities is a minor diesel fuel spill. Historically, most diesel spills have been ≤ 1 bbl, and this is predicted to be the most c ommon size in ongoing and future OCS activities in the We stern and Central Gulf of Mexico Planning Areas . As the spill size increases, the incident rate declines dramatically (MMS, 2007b ; BOEM, 201 2 b ). The median size for spills ≤ 1 bbl is 0.0 24 bbl, and the median size for spills of 1 to 10 bbl is 3 bbl ( BOEM, 2012a ). For this analysis, a small diesel fuel spill of 3 bbl is used . Operational experience suggests that the most likely cause of such a spill would be a hose rupture resulting in a loss of contents (< 3 bbl of fuel) of the fuel transfer hose

. Spill Fate

. The fate of a small fuel spill in the lease area would depend on meteorological and oceanographic conditions at the time of the spill, as well as the effectiveness of spill response activities. However, g iven the open ocean location of the lease ar ea and response actions, it is expected that impacts from a small spill would be minimal (BOEM, 201 2 b )

.
The water

- soluble fractions of diesel are dominated by two

- and three

- ringed polycyclic aromatic hydrocarbons (PAH s ), which are moderately volatile (Nat ional Research Council, 2003 a ). The constituents of these oils are light to intermediate in molecular weight and can be readily degraded by aerobic microbial oxidation. Due to its low density, diesel will not sink to the seafloor. Diesel dispersed in th e water column can adhere to suspended sediments, but this generally occurs only in coastal areas with high suspended solids loads (National Research Council, 2003 a ) and would not be expected to occur to any appreciable degree in offshore waters of the Gul f of Mexico. Diesel oil is readily and completely degraded by naturally occurring microbes ( National Oceanic and Atmospheric Administration [ NOAA ] , 2006).

For the purpose s of this EIA, t he fate of a small diesel fuel spill was estimated using NOA A’s Autom ated 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 spilled product. Based on model results, i t is estimated that more than 90% of a small diesel spill would evaporate or disperse within 24 hours. The area of sea surface exhibiting floating diesel fuel during this

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- 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 122 miles ( 196 km ) from the nearest shoreline. Modeling results indicate that a spill in the lease area w ould have a 5 % or lower probability of reaching coastal areas of Louisiana within 10 days following a spill

. By that time, essentia lly 100% of a small fuel spill would have dispersed or evaporated through natural processes, without taking into account Anadarko ’s response measures. Slicks from spills are expected to persist for relatively short periods of time
, ranging from minutes (< 1 bbl) to hours (<10 bbl) to a few days (10 to 1,000 bbl)

, and rapidly spread out, evaporate
, and disperse into the water column (BOEM, 2012b). Because of the distance of these potential spills on the OCS and the ir lack of persistence, it is unlikely that a spill would make landfall prior to dissipation (BOEM, 2012b).

Spill Response . In the unlikely event th at shipboard prevention procedures fail to avoid a fuel spill, response equipment and trained personnel would be activated so that any spill effects

w ould be localized and result only in short

- term environmental consequences. EP Section 9b provides a detailed discussion of Anadarko’ s response to a spill.



### A. 9.3 Crude Oil Spill (Worst Case Discharge)

Spill Size . In accordance wit h requirements of NTL 2010

- N06, Anadarko has estimated a WCD for th e EP of 201,530 b bl of oil per day based on a hypo thetical blowout from GC 724

- A

.

An estimate d 7 to 21 days would be required to suspend operations on a deepwater G ulf of Mexico well , mobilize to a relief well location, and begin drilling the relief well. This assumes 0 to 14 days to suspend current operations on an existing well and 7 days to mobilize and be ready to spud the relief well. The estimated duration of time required to drill the relief well i s 85 days
, for an estimated total of 92 to 106 days from time of blowout to completion of the relief well.

The maximum total volume during a blowout could be 21,362,180 bbl
, assuming 106 days for the maximum duration of a blowout multiplied by the worst case daily uncontrolled blowout volume of 201,530 bbl/day. The detailed analysis of this calculation can be found in
EP Section H.

Historically, blowouts are rare events and most do not re sult in oil spills. Holand (1997) estimated a probability of 0.0021 for a deep drilling blowout during exploration drilling based on U.S. Gulf of Mexico data. The International Association of Oil & Gas Producers ( 2010) conducted

a n updated analysis using the SINTEF 1 database and estimate d a blowout frequency of 0.0017 per exploratory well for non

- North Sea locations . As noted by MMS (2007b), from 1992 to 2005, half of blowouts lasted less than half a day, and less than 10% of blowouts resulted in spilled oil. BOEM is in the process of updating these spill frequency estimates to include the Macondo oil spill that occurred in Mississippi Canyon Block 232 in 2010 ; however, significant changes to the spill rates for the entire OCS are not anticipated ( BOEM, 2012a ). According to BSEE ’ s Final Drilling Safety Rule (75 Federal Register [FR] 63365) issued following the Macondo

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- FINspill, the baseline risk of a catastrophic blowout is estimated to be once every 26 years. Included in EP Section H are Anadarko’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. Anadarko will also comply with NTL 2010

- N 10 and the Final Drilling Safety Rule, which specif y 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 of the spill . The Oil Spill Risk Analysis (OSRA) model is a computer simulation of oil spill transport that uses realistic data for winds and currents to estimate spill trajectory

. The OSRA report by Ji et al. (2004) provides conditional contact probabilities f or shoreline segments in the Gulf of Mexico

. The results for Launch Area 45 (where the lease area is located) are presented in Table 3

. The model predicts a 0 % chance of shoreline contact within 10 days of a spill. Shoreline contact is predicted within 30 days for shorelines ranging from Calhoun, Texas, to Plaquemines Parish, Louisiana. The probability of shoreline contact within 30 days is highest in Cameron , Louisiana ( 4 %)

.
Table 3. Conditional probabilities of a spill in the lease area contacting shoreline segments based on the 30

- day Oil Spill Risk Analysis (OSRA) (From: Ji et al., 2004). Values are conditional probabilities that a hypothetical spill in the lease area (represented by OSRA Launch Area 45 ) could c ontact shoreline segments within 3, 10, or 30 days.

Shoreline Segment County or Parish and State Conditional Probability of Contact 1 (%) 3 Days 10 Days 30 Days
C07 Calhoun, Texas

-- -- 1
C08 Matagorda, Texas

-- -- 1
C09 Brazoria, Texas

-- -- 1
C10 Galveston, Texas

-- -- 2
C12 Jefferson, Texas

-- -- 1
C13 Cameron, Louisiana

-- -- 4
C14 Vermillion, Louisiana

-- -- 2
C15 Iberia, Louisiana

-- -- 1
C16 St. Mary, Louisiana

-- C17 Terrebonne, Louisiana

-- -- 2
C18 LaFourche, Louisiana

-- -- 1
C19 Jefferson, Louisiana

-- -- -- C20 Plaquemines Parish, Louisiana

-- -- 2

1 Conditional probability refers to the probability of contact within the stated time period, assuming that a spill has

occurred (

-- indicates <0.5%).

The original OSRA modeling runs reported by Ji et al. (2004) did not evaluate the fate of a spill over time periods exceeding 30 days, nor d id they estimate the fate of a release that continues over a period of weeks or months. As noted by J i et al. (2004 )

, the OSRA model does not consider the chemical composition or biological weathering of oil spills, the spreading and splitting of oil spills, or spill response activities. The model does not specify a particular spill size but has been used by BOEM to evaluate contact probabilities for spills greater than 1,000 bbl.

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- FINBOEM (2012b) conducted additional OSRA modeling to simulate a spill that continue d for 90 consecutive days, with each trajectory tracked for 120 days during each of the four seasons. Th e spatial resolution wa s limited, with five hypothetical launch points in the 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 reserve s. The launch point most appropriate for modeling a spill in the lease area is Launch Point 3

. The 120

- day OSRA results for Launch Point 3 are presented in Table 4

.
Table 4

. Conditional probabilities of a spill in the lease area contacting shoreline segm ents based on the 120

- day Oil Spill Risk Analysis (OSRA). Values are conditional probabilities that a hypothetical spill in the lease area could contact sho reline segments within 120 days (Modified from: BOEM, 2012b, Appendix C)

.

Season Winter Spring Summer Fall

Day s 3 10 30 120 3 10 30 120 3 10 30 120 3 10 30 120 County or Parish, State Conditional Probability of Contact 1 (%)

Cameron, TX

-- -- -- 2

-- -- -- -- -- -- -- 2

-- -- -- 2 Willacy, TX

-- -- -- 3

-- -- -- -- -- -- -- 2

-- -- -- 3 Kenedy, TX

-- -- -- 8

-- -- -- 1

-- -- -- 9

-- -- -- 5 Kleberg, TX

-- -- 1 6

-- -- -- -- -- -- -- 4

-- -- 1 6 Nueces, TX

-- -- 1 6

-- -- -- -- -- -- -- 2

-- -- 1 2 Aransas, TX

-- -- -- 5

-- -- -- 1

-- -- -- 3

-- -- -- 2 Calhoun, TX

-- -- 1 6

-- -- -- -- -- -- -- 6

-- -- 1 4 Matagorda, TX

-- -- 2 17

-- -- 3 4

-- -- -- 11

-- -- 1 6 Brazoria, TX

-- -- 3 12

-- -- 1 3

-- -- 2 8

-- -- 1 5 Galveston, TX

-- -- 3 10

-- -- 3 6

-- -- 2 5

-- -- 1 4 Jefferson, TX

-- -- 1 4

-- -- 7 9

-- -- 1 1

-- -- -- 2 Cameron, LA

-- -- 1 4

-- -- 11 12

-- 1 1 4

-- -- -- 4 Vermilion, LA

-- -- 1 2

-- -- 5 6

-- 1 1 2

-- -- -- -- Iberia, LA

-- -- -- 1

-- -- 4 4

-- -- -- -- -- -- -- -- Terrebonne, LA

-- 1 2 3

-- 4 12 14

-- -- -- 2

-- -- -- -- Lafourche, LA

-- -- 1 1

-- 2 8 10

-- -- 1 2

-- -- -- -- Jefferson, LA

-- -- -- 1

-- -- 2 2

-- -- 1 1

-- -- -- -- Plaquemines, LA

-- -- -- 1

-- 2 10 12

-- -- 1 2

-- -- -- -- Jackson, MS

-- -- -- -- -- -- 1 1

-- -- -- -- -- -- -- -- Baldwin, AL

-- -- -- -- -- -- 1 1

-- -- -- -- -- -- -- -- Bay, FL

-- -- -- -- -- -- -- 1

-- -- -- -- -- -- -- -- Franklin, FL

-- -- -- 1

-- -- -- -- -- -- -- -- -- -- -- -- Monroe, FL

-- -- -- -- -- -- -- -- -- -- -- 1

-- -- -- 1
Miami

- Dade, FL

-- -- -- -- -- -- -- -- -- -- -- 1

-- -- -- -- State Coastline Conditional Probability of Contact 1 (%)

Texas

-- -- 12 78

-- -- 14 24

-- -- 6 54

-- -- 4 41
Louisiana

-- 1 6 14

-- 9 52 60

-- 1 4 13

-- -- -- 6 Mississippi

-- -- -- -- -- -- 1 1

-- -- -- -- -- -- -- -- Alabama

-- -- -- -- -- -- 1 1

-- -- -- -- -- -- -- -- Florida

-- -- -- 1

-- -- 1 4

-- -- -- 2

-- -- -- 2

1 Conditional probability refers to the probability of contact within the stated time period, assuming that a spill has

occurred (

-- indicates <0.5%).

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- FINFor this launch point, potential shoreline contacts after 120 days range from Cameron County, Texas (at the Texas/Mexico border) to Miami

- Dade County in southeastern Florida . Based on statewide contact probabilities after 120 days, Texas and Louisiana shorelines have the highes t likelihood of contact during all four seasons, with Louisiana having higher probabilities in spring (60%) and Texas having higher probabilities during all other seasons (ranging from 41% to 78%). The modeling predicts a 1% probability of a spill contact ing Alabama and Mississippi shorelines, but only during spring. The modeling predicts that Florida shorelines could be contacted in any season, with statewide probabilities ranging from 1% to 4% . Based on the 120

- day trajectories, counties or parishes wi th more than 10% contact probability during any season include Matagorda , Brazoria, Galveston, and Cameron Counties in Texas and Terrebonne , Lafourche, and Plaquemines Parish es in Louisiana

. 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 mo deling 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

. 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 (National Research Council, 2003 a ).

Weathering decreases the concentration of oil and produces changes in its chemical composition, physical properties, and toxicity. The more toxic, light aromatic and aliphatic hyd rocarbons 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 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 i n the oil on the water surface.

Spill Response

. BOEM has issued NTLs following the Macondo spill that clarify additional oil spill prevention and response planning requirements. These NTL s are summarized in Table 1

.
Anadarko’s Sub

- Regional OSRP was last approved on 2 5 September 2013

. The OSRP provides a detailed plan for Anadarko to respond to rapidly and effectively manage oil spills that may result from drilling and production operations. The OSRP contains det ailed information on "Quick Response" procedures
, including:

• responsibilities of all Anadarko and contract perso nnel to report any observed discharge from known or unknown sources;

• procedures to locate and determi ne the size of a discharge; and

• contact information for alerting the spill management team
, complete with names, phone numbers, and locations.

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- FINIn the event of a WCD, Anadarko has access to surface and subsea response/containment capabilities that could be implemented through various organizations under contract. Anadarko’s primary spill response equipment provider is Clean Gulf Associates (CGA).

CGA has fou r skimming vessels capable of operating in shallow waters, nearshore areas , and offshore areas

. These vessels have o leophilic brush pack skimming systems operating in troug hs built into the hulls ; below

- deck storage ; and marine electronics packages includ ing marine, aircraft
, and company

- frequency radios
, radar
, moving map plotters
, GPS
, satellite phone s , and depth finders. CGA also offers nine Fast Response Systems staged throughout the Gulf of
Mex ico available for offshore use.

The CGA high

- volume open sea skimmer ( HOSS ) barge consists of a skimming system built into an oil recovery barge. There are four 1,000

- bbl recovered oil storage tanks built into the hull where oil can be separated and offloaded. Skimming operations are conducted from the control room overlooking the skimmer deck. The estimated daily recovery capacity for the HOS S barge is approximately 43,000 bbl

. CGA is currently adding to its equipment stockpile and has acquired 11 sets of Koseq skimming arms and two Aqua Guard skimmers. In a ddition, an x

- band radar/infrared tracking system is installed on the HOSS barge. Additional CGA equipment can be referenced on line at http://www.cleangulfassoc.com/equipment

.
Anadarko also has a con tract with the Marine Spill Response Corporation (MSRC) for additional spill response equipment. MSRC has a dedicated fleet for the Atlantic/ Gulf of Mexico region and additional available equipment staged throughout the U

. S. MSRC equipment staged through out the Gulf of Mexico includes 7 oil spill response vessels, 2 fast response vessels, 5 oil spill response barges, 5 platform supply vessels, and 15 shallow water barges. Various equipment is outfitted with x

- band radar and infrared technology for detecting surface oil

.

MSRC expanded its resources and capability in the Gulf of Mexico with particular focus on deep
water , known as " Deep Blue. " Additional MSRC capabilities and a complete equipment listing

are available on line at http://www.msrc.org/

. Anadarko is a member of the Marine Well Containment Company (MWCC). In the event of an incident, MWCC can provide a 15,000

- psi single ram capping stack and dispersant injection capability. MWCC can install and op erate the interim containment system, including subsea flowlines, manifold s , and risers. The interim system is engineered to be used in depths up to 3,048 m (10,000 ft) and has the capacity to contain 60,000 bbl of liquid per day (and 120 million standard cubic feet per day of gas) with potential for expansion.

See EP Section H for a detailed description of Anadarko ’s site

- specific spill response measures for this plan.



### A. 9.4 Other Accidents Not Analyzed in Detail

BOEM (2012b) discusses other types of accidents , including chemical spills, pipeline failures, 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 accident s along with a hydrogen sulfide ( H 2 S ) release are discussed briefly in the following subsections . T here are no other site

- specific issues for the drilling of the well s proposed in this EP.

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- FINChemical Spills

. Chemicals are stored and used to condition drill muds , as well as during production activities and well completions, stimulation s , and workover procedures. A study of environmental risks of chemical products used in OCS activities determined that only two chemicals could potentially affect the marine e nvironment: zinc bromide a nd ammonium chloride (Boehm et al., 2001). The risk of a chemical spill is very low, and m ost chemicals are either nontoxic or used in small quantities (BOEM, 2012a,b) . No significant impacts are expected from chemical spills.

Riser Disconnect SBM Spills

. There is the potential for an SBM spill due to a riser disconnect (BOEM, 2012a,b). In the event of an SBM spill, there would be short

- term, localized impacts on water quality
, and the potential for localized benthic impacts d ue to SBM deposition on the seafloor

. Benthic impacts would be similar to those described in Section C.2.1

.
Vessel Collisions

. BOEM 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
, f ires resulted from hydrocarbon releases. To date, the largest diesel spill associated with a collision occurred in 1979 when an anchor

- handling vessel collided with a drilling platform in the Main Pass leas e area, spilling 1,500 bbl of diesel fuel

. Diesel fuel is the product most frequently spilled
, but oil, natural gas, corrosion inhibitor, hydraulic fluid, and lube oil also have been released as the result of vessel collision s

. Human error account ed for approximately half of all reported vessel collisions from 2006 to 2009. As summarized by MMS (2007b ) and BOEM (201 2 b ), vessel collisions occasionally occur during routine operations. Some of these collisions have caused spills of diesel fuel or chemicals. Anadarko will comply with all USCG

- and BOEM

- mandated safety requirements to minimize the p otential 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 synthe tic drilling fluid or loss of oil. Not all l oss of well control events result in blowouts (BOEM, 2012 a,b , 2013)

. In addition to the potential release of gas, condensate, oil, sand, or water, the loss of well control can also resuspend and disperse bottom sediments (BOEM, 2012b). BOEM (2012 a,b
, 2013) noted that most OCS blowouts have resulted in the release of gas.

Anadarko has a robust system in place to prevent loss of well control. M easures 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 the NTL 2010

- 06 package submitted with the EP
, as required by BOEM

. The potential for a loss of well control event will be minimized by adhering to the requirements of ap plicable regulations such as the Final Drilling Safety Rule and NTL 2010

- N10
, which specify additional safe ty measures for OCS activities.

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- FINH 2 S Release

. The wells proposed in th e EP will test the Pliocene and Pleistocene section s of the subbottom geological formation

. The proposed GC 724 A well will only penetrate sections that have been previously penetrated by four of the GC 768 we lls within approximately 250 ft of the surface location of proposed well, and had no recorded amounts of H 2 S

. There fore, Anadarko is requesting that the area for the wells proposed in th e EP be classified as a zone in which the absence of H 2 S has been confirmed

.



## B. Affected Environment

The lease area is in the central Gulf of Mexico, 122 miles ( 196 km ) from the nearest shoreline
, 135 miles ( 217 km ) from the onshore support base at Port Fourchon, Louisiana
, and 160 miles ( 258 km ) from the helicopter base at Houma, Louisiana ( Figure 1 ). Based on the site clearance
survey s conducted by Fugro GeoServices, Inc. ( 2003 )

, water depth s at the wellsites range from 1,573 to 1,695 m ( 5,160 to 5,560 ft) ( Figure 2 ).

The seafloor surrounding the proposed wellsites is smooth and stable , with one seafloor fault south of and within approximately 1,300 ft of the proposed surface location . Seafloor gradients

are less than 1 degree ( Fugro GeoServices, Inc.
, 2003 )

. Several existing structures are present near the proposed locations, including three existing wells, two 6

- inch pipelines, an umbilical, and numerous cables. No areas of high seafloor amplitude occur within 610 m (2,000 ft) the proposed well locations. No areas with the potential for high

- density deepwater benthic or chemosynthetic communities were identified by Fugro GeoServices, Inc. ( 2003 ) within 610 m (2,000 ft) of the proposed wellsites.

A detailed description of the regional affected environment, including meteorology, oceanography, geology, air and water quality, benthic communities, threatened and endangered species, biologically sensitive resources, arch aeological resources, socioeconomic conditions, and other marine uses i s provided in MMS ( 2007b ) and BOEM (2012a,b, 2013 ). These regional descriptions remain valid and are incorporated by reference. B rief descriptions of each potentially affected resourc e, including site

- specific and/or new information if available
, are presented in Section C

.

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- FINFigure 2. Bathymetric map of the lease area showing the surface hole location s of the proposed wellsites.

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- FIN

## C. Impact Analysis

This section analy z es the potential direct and indirect impacts of routine activities and accidents. Impacts have been analyzed extensively in multi

- lease

- sale EISs for the Western and Central Gulf of Mexico Plann ing Areas (MMS, 2007b ; BOEM, 2012b, 2013 )

. The information in these documents is incorporated by reference. Potential s ite

- specific issues are addressed in this section.



## C. 1 Physical/Chemical Environment

C. 1.1 Air Quality

There are no site

- specific air q uality 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 (BOEM, 2012a)

. In general, ambient air quality o f coastal counties along the Gulf of Mexico is relatively good (BOEM, 2012 b ). As of 5 December 2013 , Louisiana, Mississippi, Alabama, and Florida Panhandle coastal counties and parishes are in attainment of the National Ambient Air Quality Standards (NAAQS) for all criteria pollutants (USEPA, 2013 ). One coastal metropolitan area in Texas ( Houston

- Galveston

- Brazoria) is a nonattainment area for 8

- hour ozone. One coastal metropolitan area in Florida (Tampa) is a nonattainment a rea for lead based on the 2008 s tandard.

As noted earlier, based on calculations made pursuant to applicable regulat ions, emissions from drilling activities are not expected to be significant because they are below exemption levels. Therefore, the only potential effects to air quality would be from routine air pollutant emissions,

a small fuel spill , and a large oil sp ill

.

BOEM has reexamined the analysis for air quality presented by 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 impact s on ai r quality presented in BOEM ( 2012 b ).



### 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 combus tion of fuels occurs primarily i n diesel

- powered generators, pumps, or motors as well as from lighter fuel motors. Primary air pollutants typically a ssociated with OCS activities are suspended PM, SO x , NO x , 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
, anticipated emission rates
, anticipated heights of emission sources , and the resulting anticipated pollutant concentrations. T he incremental contribution to cumulative impacts from activities similar to Anadarko’s proposed activities is not significant and will not cause or contribute to a violation of NAAQS (MMS, 2007b
, 2008). Since BOEM completed the

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- FINlease sale EISs, the USEPA has adopted a new short

- term NAAQS for nitrogen dioxide (NO 2 ) . 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 Anadarko’ s propose d EP are not likely to contribute to violations of any NAAQS onshore.

Greenhouse gas emissions contribute to climate change, with important impacts on temperature, rainfall, frequency of severe weather, ocean acidification, and sea level rise (Intergovernmental Panel on Climate Change, 2007

, 2014 ). 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 cha nge impacts evaluated in the Programmatic EIS (BOEM, 2012 a )

. Carbon dioxide (CO 2 ) and methane ( CH 4 ) emissions from the project would constitute a small incremental contribution to greenhouse gas emissions from all OCS activities. According to recent Prog rammatic and OCS lease sale EISs (BOEM, 2012a,b)

, estimated CO 2 emissions from OCS oil and gas sources represent 0.4% of the U.S. total . A ll OCS activities combined contribute approximately 0.005% to total global CO 2 emissions

. Because of 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 MMS ( 2007b)

, emissions of air pollutants from routine activities in the Central and Western Gulf of Mexico Planning Area s are projected to have minimal impacts on 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 EP Section G ) p repared in accordance with BOEM requirements shows that the projected emissions are below exemption levels; therefore, according to 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

. The Breton Wilderness Area, which is part of the Breton National Wildlife Refuge (NW R), is designated under the Clean Air Act as a Prevention of Signif icant Deterioration (PSD) Class I air quality area. BOEM is required to notify the National Park Service (NPS) and U.S. Fish and Wildlife Service ( USFWS ) if emissions from proposed project s 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 186 miles ( 300 km) from the Breton Wilderness Area
, and no air quality impacts on the Wilderness Area are expected. Anadarko will comply with all BOEM r equirements regarding air emissions.


### Impacts of a Small Fuel Spill

Potential impacts o f a small spill on air quality are expected to be consistent with th os e analyzed and discussed in MMS ( 2007b ) and BOEM ( 2012 a,b , 2013 ). The probability of a small spill would be minimized by Anadarko’ s preventative measures during routine operati ons , including fuel transfer. In the unlikely event of a spill, implementation of Anadarko’ s OSRP could reduce the potential impacts

. EP Section H 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.

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- FINA 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 more than 90% of a small diesel spill would evaporate or disperse within 24 hours. The sea surface area 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 natural dispersion (see Section A.9.2 ).



### Impacts of a Large Oil Spill
Potential impacts of a large oil spill on air quality are expected to be consistent with th os e analyzed and discussed by MMS ( 2007b ) and BOEM ( 2012 a,b , 2013 ).

A large oil spill could 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 effec ts 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 NO x , SO x , CO, and PM as well as greenhouse gases. However, in situ burning would occur only if authorized by the USEPA.

Due to the lease area’s distance from the nearest shoreline, most air quality impacts would occur in offshore waters with minimal chance s 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 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 a re 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 187 miles ( 301 km) f r om the Macondo spill site in Mississippi Canyon Block 232 . Based on the general circulation pattern observed in the Gulf of Mexico and in satellite imagery, the surface slick from that discharge extend ed over the GC lease area during the spill
, and local water quality may have been affected

.

IPFs that could affect water quality are effluent discharges and two types of accidents

– a small fuel spill and a large oil spill.


### 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 muds and cuttings. SBMs will be collected on the rig and either reused by the vendor or transported to Port Fourchon , Louisiana
, for recycling and disposal at an approved facility. Cuttings wetted with S BMs will be discharged to the seafloor at the drillsite in accordance with the NPDES

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- FINpermit. All NPDES permit limitations and requirements will be met. There will be no persistent impacts on water quality in the lease area ( National Research Council
, 1983; Neff, 1987 ; Neff et al., 2000 ).

Treated sanitary and domestic wastes , including those from support vessels, may have a transient effect on water quality in the immediate vicinity of these discharges. All NPDES permit limitations and requirements as well as USCG regulations (as applicable) will be met ; therefore, l ittle 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 i n 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 is expo sed will be collected
, and oil and water will be separated to meet NPDES permit requirements. Based on adherence to permit limits and applicable regulations, l ittle or no impact on water quality is anticipated.

Other discharges in accordance with the NPDE S permit, such as desalination unit brine and uncontaminated cooling water, fire water, and ballast water
, are expected to dilute rapidly
, resulting in little or no impact on water quality.



### Impacts of a Small Fuel Spill
Potential impacts of a small spill on wate r quality are expected to be consistent with th os e analyzed and discussed in MMS ( 2007b ) and BOEM ( 2012 a, b , 2013 ). The probability of a small spill would be minimized by Anadarko ’s preventative measures during routine operations including fuel transfer. In the unlikely event of a spill, implementation of Anadarko’s OSRP could potentially help mitigate and reduce the impacts. EP Section H provides detail on spill response

measure s 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 produ ce 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 effectivene ss of spill response measures. However, i t is estimated that more than 90% of a small diesel spill would evaporate or disperse within 24 hours (see Section A.9.2 ). The sea surface area 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 PAH s , which are moderately volatile (National Research Council, 2003 a ). The constituents of these oils are light to intermediate i n molecular weight and can be readily degraded by aerobic microbial oxidation. Because the density of diesel is less than the density of seawater, diesel will not sink and pool 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 (National Research Council, 2003 a ) 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).

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- FINA 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 underta ken as well as natural attenuation (see Section A.9.2 ).



### Impacts of a Large Oil Spill
Potential impacts of a large oil spill on wate r quality are expected to be consistent with th os e analyzed and discussed in MMS ( 2007b ) and BOEM ( 2012 a,b , 2013 ). A large s pill w ould 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 oceanographi c 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 wh en subsea dispersants are applied at the wellhead (Camilli et al., 2010; Hazen et al., 2010; Joint Analysis Group, 2010a,b,c). However, subsea dispersants would be applied only after approval from the USEPA. Small droplets in the water may adhere to susp ended sediment s and be removed from the water column (Operational Scientific Advisory Team [ OSAT ], 2010).

Recent analyses of the full set of samples associated with the Macondo spill have confirmed that the application of subsurface dispersants resulted in subsu rface hydrocarbon plumes (Spier et al., 2013). A report by Kujawinski et al. (2011) indicates that chemical components of subsea dispersants used during the Macondo spil l persisted for up to 2 months and were detect ed up to 186 miles (300 km) from the wellsite in water de pth s of 3,280 to 3,937 ft (1,000 to 1,200 m). Although dis persants were detected by laboratory analysis in 353 of the 4,114 water samples, concentration s were significantly below the chronic screening level for dispersant s (BOEM, 2012b ).

Because of the lease area ’s distance 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 ( Table 4 ). The 30

- day OSRA modeling ( Table 3 ) indicates a 4 % conditional probability of contact in Cameron , Louisiana within 30 days. A very low conditional probability of contact ( 1 % to 2 % ) is predicted by the 30

- day OSRA for other shorelines between Calhoun, Texas and Plaquemines Parish, Louisiana

.


## C. 2 Seafloor Habitats and Biota

W ater depth s at the proposed wellsites range from 1,573 to 1,695 m ( 5,160 to 5,560 ft)

. The site clearance surveys conducted by Fugro GeoServices, Inc. ( 2003 ) identified no hazards at the seafloor that preclude the proposed wellsites from exploratory drilling. There is no evidence of high

- density deepwater benthic or chemosynthetic communiti es within 610 m (2,000 ft) of the proposed wellsites ( Fugro GeoServices, Inc.
, 2003 )

.


### C. 2.1 Soft Bottom Benthic Communities

There are no site

- specific benthic community data from the lease area. However, data from the Northern Gulf of Mexico Continental S lope Habitats and Benthic Ecology Study (Wei, 2006; Rowe and Kennicutt, 2009) can be used to describe typical benthic communities that occur at similar water depths elsewhere in the region

. Table 5 summarizes data collected at nearby stations in water depths similar to the proposed drilling area.

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- FINTable 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 (Adapted f rom: Wei, 2006; Rowe and Kennicutt, 2009).

Station Water Depth (m) Abundance Meiofauna (individuals/m 2 ) Macroinfauna (individuals/m 2 ) Megafauna (individuals/ha)

NB2 1,530 168,276 1 ,700 570
NB3 1,875 165,245 1,342 191 Meiofaunal and megafaunal abundances from Rowe and Kennicutt (2009); macroinfaunal abundance from Wei (2006).

Densities of meiofauna (animals passing through a 0.5

- mm s ieve but retained on a 0.062

- mm sieve) in water depths representative of the lease area ( 1,573 to 1,695 m ) typically range from approximately 100,000 to 300,000 individuals/ m 2 (Rowe and Kennicutt, 2009 ). Nematodes, nauplii (crustacean larvae) , and harpacticoid copepods were the three dominant meiofaunal groups, accounting for approximately 90% of total abundan ce.
The benthic macroinfauna is characterized by small mean individual sizes and low densities, both of which reflect the meager primary production in Gulf of Mexico surface waters (Wei, 2006). Based on an equation presented by Wei (2006) in which d ensities decrease exponentially with water depth , macroinfaunal densities in the water depths of the lease area are expected to be approximately 2,119 individuals/m 2 ; however, actual densities are unknown and pften highly variable.

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 ar e divided ho r izontally. The lease area is located in Zone 3 W , which contains the most complex bathymetric features in the northern Gulf of Mexico, including the Alaminos Canyon
, basin sites,

non

- basin sites, and the base of the Sigsbee Escarpment

. The fi ve most abundant species in Zone 3 W were the polychaetes Paraonella monilaris , Tachytrypane sp. A
, and Levinsenia uncinata and the bivalves Heterodonta sp. B and Heterodonta sp. C (Wei, 2006).

Megafaunal densities from nearby s tations ranged from 191 to 570 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 also are 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 0.5 to 1.5 g C/m 2 in the top 15 cm (6 in.) of sediments (Rowe and Kennicutt, 2009).

IPFs potentially affecting benthic communities are physical disturbance to the seafloor, effluent discharges (drilling muds and cuttings), and a large oil spill resulting from a well blowout at the seafloor. A small fuel spill would not affect benthic communities because the diesel fuel would float and di ssipate on the sea surface.

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### Impacts of Physical Disturbance to the Seafloor
In water depths such as those encountered in the lease area, the areal extent of seafloor impacts will be small compared to the lease area itself

. DP drilling vessels disturb the seafloor only around the wellbore where the bottom template and BOP are located. Depending on the specific well configuration, this area is generally 0.25 ha (0.62 ac) per well.

S oft bottom communities are ubiquitous along the northern Gulf of Mexico cont inental slope (Gallaway, 1988; Gallaway et al., 2003; Rowe and Kennicutt, 2009 )

, and i mpacts from the physical disturbance of the seafloor during this project likely will have no significant impact on soft bottom benthic communities in the region.



### Impacts of Effluent Discharges
Drilling muds 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 t he same chem icals used in
water

- based drilling 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 adj acent areas. Because some deep sea biota grow and reproduce slowly, recovery may require several years for the area within meters to tens of meters of the wellbor e

. 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 cond ucted 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 eleva ted 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 flu id 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 H 2 S predominate (Continental Shelf Assoc iates, 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.

T he areal extent of impacts from dril ling discharges will be small. Soft bottom communities are ubiquitous along the northern Gulf of Mexico continental slo pe (Gallaway, 1988; Gallaway et al., 2003; Rowe and Kennicutt, 2009). D rilling discharges during this project likely will have no significant impact on soft bottom benthic communities in the region

. 

### Impacts of a Large Oil Spill
The most likely effects of a subsea blowout on benthic communities would be within a few hundred meters of the wellsite. MMS (2007b) estimat ed t hat a severe subsurface blowout

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- FINcould 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) of 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 ).

Discussions in MMS ( 2007a, 2008) and BOEM (2013) i n dicat ed 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 sp ill location. However, during the Macondo spill, subsurface plumes were reported in water depth s of approximately 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 s ubsurface plumes apparently resulted from the use of subsea dispersants at the wellhead (Joint Analysis Group, 2010c ; Spier et al., 2013 ). While the behavior and impacts of subsurface plumes are not well known, a subsurface plume could contact the seafloo r and affect benthic communities beyond the 300

- m (984

- ft) radius estimated by MMS (2007a, 2008)

, depending on its extent, trajectory, and persistence (Spier et al., 2013 ) . This contact could result in smother ing or toxicity to benthic organisms. The aff ected area likely would be recolonized by benthic organisms over a period of months to years (National Research Council, 2003 a ).



### C. 2.2 High

- Density Deepwater Benthic Communities

As defined by NTL 2009

- G40, high

- density deepwater benthic communities are f ea tures or areas that could support chemosynthetic communities, deepwater corals
, and other associated hard bottom communities. Chemosynthetic communities were discovered in the central Gulf of Mexico in 1984 and have been studied extensively (MacDonald, 20 02). Deepwater coral communities are also known from numerous locations in the Gulf of Mexico (Brooke and Schroeder, 2007; CSA International, Inc., 2007 ; Brooks et al., 2012 ). These communities occur almost exclusively on authigenic carbonates created by chemosynthetic communities.

Mo nitoring programs on the Gulf of Mexico continental slope have shown that benthic impacts from drilling discharges typically are concentrated within approximately 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) . In water depths such as those encountered in the project area, DP drilling vessels disturb the seafloor only around the wellbore (SHL) where the bottom t emplate and BOP are located. Depending on the specific well configuration, this area is approximately 0.25 ha (0.62 ac) per well.

The site clearance survey s of the proposed wellsites did not identify any features that could support high

- density deepwater benthic or chemosynthetic communities within 610 m (2,000 ft) of the proposed drilling mud /cuttings discharge locations ( Fugro GeoServices, Inc.
, 2003 ). The nearest known chemosynthetic community site is approximately 31 miles ( 50 km) north

- north east of the project area in GC Block 287

. The neare st identified deep water coral communities are located 12 miles ( 20 km) west

- southwest of the project area in GC Block 852

. The only IPF identified for this project tha t could affect high

- density deepwater benthic communities is a large oil spill 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 and effluent discharge are n ot considered IPFs for deepwater benthic

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- FINcommunities because these communities are not expected to be present near the proposed wellsites

. 

### Impacts of a Large Oil Spill
Previous analyses (MMS, 2007a, 2008 ; BOEM, 2012a ) concluded that oil spills would be unl ikely 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, subsu rface plumes were reported at a water depth of approximately 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 s ubsea 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 (98 4

- ft) radius estimated by MMS (2007a, 2008)

, depending on its extent, trajectory, and persistence (Spier et al., 2013)

. Oil plumes that contact sensitive benthic communities before degrading could potentially impact the resource (BOEM, 2012b). 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 oi l remaining in the Gulf of Mexico from the blowout are still unknown due to the depth and magnitude of th e event. Hazen et al. (2010) reported changes in plume hydrocarbon composition with distance from the source . I ncubation 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 de ep 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 consistent 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 dro plets 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 i n 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 an d diseases) (BOEM

, 2012 a )

. The potential for a spill to affect deepwater corals is indicated by preliminary findings from a n October 2010 survey of deepwater coral habitats near the Macondo spill site (BOEMRE, 2010). Government and academic researchers we re working at a site 1,400 m (4,600 ft) deep and approximately 7 miles (11 km) southwest of the Macondo wellhead when they observed dead and dying corals with sloughing tissue and discoloration. Much of the soft coral observed in an area measuring approxi mately 15 by 40 m (50 by 130 ft) was covered by what appeared to be a brown flocc ulent substance. O f 40 large corals, 90% were heavily affected
, show ing dead or dying parts and discoloration. Another site 400 m (1,312 ft) farther away had a colony of sto ny

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- FINcorals similarly affected and partially covered with a similar brown substance. Based on hopanoid petroleum biomarkers from the brown flocculent substance , researchers concluded that the colony contained oil from the Macondo spill. The injured and dea d corals were in an area where a subsea plume of oil had been documented during the spill in June 2010

. C orals elsewhere in the Gulf of Mexico outside the area affected by the plume did not appear to be experiencing higher mortality. The research team co ncluded that the observed coral injuries likely resulted from exposure to the subsurface o il plume (White et al., 2012). Apparent recovery of some affected areas by March 2012 correlated negatively with the proportion of the coral covered with floc culent in late 2010 (Hsing et al., 2013).



### C. 2.3 Designated Topographic Features

The block s are not within or near a designated topographic feature or a no

- activity zone as identified in NTL 2009

- G39 . The nearest designated topographic feature is Ship Shoal Sout h in E wing Bank Block 94 7
, 54 miles ( 87 km) north of the lease area.

There are no IPFs associated with either routine operations or accidents that could cause impacts to designated topographic features 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 be expected to 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 Botto m (Pinnacle Trend) Stipulation. As defined by
NTL 2009

- G39, the nearest Pinnacle Stipulation Block is M ain P ass Block 290
, located 203 miles ( 327 km) northeast of the lease area.

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 th e 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 be expected to 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 pertains to
seagrass communities and low

- relief hard

- bottom reef within the Eastern Gulf of Mexico Planning Area blocks in water depths of 100 m (328 ft) or less and portions of Pensacola and Destin Dome Area b locks in the Central Gulf of Mexico Planning Area

. The nearest block covered by the L ive B ottom S tipulation, as defined by NTL 2009

- G39, is Destin Dome Block 573
, located 243 miles ( 390 km) northeast of the leas e area.

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- FINThere 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 differ ence in water depth

. Near

- bottom currents in the region are predicted to flow along the isobaths (Nowlin et al., 2001) and typically would not be expected to 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 ( MM PA )

. Endangered or threatened species that may occur in the project area and along the northern Gulf C oast are listed in Table 6 . The table also indicates the location of critical habitat (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; a nd (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 in the marine environment , and fishes in the Gulf of Mexico. The USFWS has jurisdiction for ESA

- listed birds
, the West Indian m anatee , and sea turtles on their nesting beaches

. As mandated by the ESA, MMS consulted NMFS and the USFWS on possible and potenti al impacts from the proposed leasing in the Gulf of Mexico on endangered/threatened species and their designated critical habitat (MMS

, 2007a
, b)

. A B iological A ssessment was prepared for each consultation. The formal ESA consultation with NMFS was conclu ded 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 the USFWS was concluded with a letter dated 1 4 September 2007. The USFWS concurred with MMS’s determination that proposed actions of the Five

- Year Leasing Plan were not likely to adversely affect endangered / threatened species or designated critical habitat under USFWS jurisdiction. Following the Ma condo spill
, BOEMRE requested to reinitiat e an ESA consultation with both NMFS and the USFWS on 30 July 2010. NMFS responded with a letter to BOEMRE on 24 September 2010 , and t he USFWS responded with a letter to BOEMRE on 27 September 2010. At present, N MFS and the US FWS have placed th e 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 remain s in effect (BOEM, 2012b)

. The existing consultation recognize s that BOEM

- required mitigation and other

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- FINreasonable and prudent measures should reduce the likelihood of impacts f rom 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, p iping p lover, w hooping c rane, Gulf sturgeon, and four subspecies of beach m ouse . Critical habitat has been designated for all of these species as indicated in Table 6 and are discussed in individual sections.

Table 6

. Federally listed endangered and threatened species that could potentially occur in the lease area and along the northern Gulf Coast.

Species Scientific Name Status Potential Presence Critical Habitat Designated in Gulf of Mexico Lease Area Coastal

Marine Mammals

Sei whale Balaenoptera borealis E X a

-- None Blue whale Balaenoptera musculus E X a

-- None
Fin whale Balaenoptera physalus E X a

-- None North Atlantic right whale Eubalaena glacialis E X a

-- None Humpback whale Megaptera novaeangliae E X a

-- None Sperm whale Physeter macrocephalus E X

-- None

West Indian manatee Trichechus manatus latirostris E

-- X Florida (Peninsular)

Sea Turtles

Loggerhead turtle Caretta caretta T X X Proposed b
Green turtle Chelonia mydas T, E c 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
In vertebrates

Elkhorn coral Acropora palmata T d

-- X Flower Garden Banks Terrestrial Mammals

Beach mice (subspecies: Alabama, Choctawhatchee, Perdido Key, St. Andrew) Peromyscus polionotus E

-- X Alabama and Florida (Panhandle) beaches

Abbreviations: E = endangered; T = t hreatened.

a The sei, blue, fin, North Atlantic right, and humpback whales are rare or extralimital in the Gulf of Mexico and are unlikely to be present in the lease area.

b In September 2011, the National Marine Fisheries Service (NMFS) and U.S. Fish and Wildlife Service (USFW S) listed nine distinct population segments (DPS) of loggerhead turtles under the Endangered Species Act. The Northwest Atlantic Ocean DPS was designated as threatened (76 FR 58868). NMFS and the USFWS have proposed to designate critical habitat for this DPS, including beaches in Jackson County, Mississippi; Baldwin County, Alabama; and Bay, Gulf, and Franklin Counties in the Florida Panhandle , as well as several counties in southwest Florida and the Florida Keys (78 FR 18000).

c The green sea turtle is t hreatened, except for the Florida breeding population, which is listed as endangered.

d In December 2013, NMFS proposed to redesignate elkhorn coral as endangered (77 FR 73220).

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- FINTwo other coastal species ( b ald e agle and b rown p elican) discussed in MMS (20 07b) and BOEM (2012b) are no longer federally listed as endangered or threatened . T hese are discussed in Section C.4.2

. There are five sea turtle and six marine mammal species known to occur within OCS and slope waters of the Gulf of Mexico that are curre ntly listed as endanger ed and threatened by the ESA

. The listed sea turtles include the l eatherback turtle , Kemp's ridley turtle , hawksbill turtle, loggerhead turtle, and green turtle. Listed marine mammal species include one odontocete ( sperm whale ) and five mysticete s ( blue whale, fin whale, humpb ack whale, North Atlantic right whale, and sei whale) ( Pritchard, 1997; Würsig et al., 2000 ). No critical habitat has been designated for these species in the Gulf of Mexico.

The sperm whale and five species o f sea turtles are the only endangered or threatened species likely to occur in or near the lease area. No critical habitat has been designated for these species in the Gulf of Mexico. However, critical habitat has been proposed for the loggerhead turtle as discussed in Section C.3.5

. The five endangered mysticete s listed previously also have been reported to occur in the Gulf of Mexico but are considered rare or extralimital there (Würsig et al., 2000). No critical habitat has been designated for these s pecies in the Gulf of Mexico.



### C. 3.1 Sperm Whale (Endangered)

The only endangered marine mammal likely to be present in or near the project area is the sperm whale ( Physeter macrocephalus )

. Resident populations of s perm whales occur within the Gulf of Mexi co ; a species description is presented in MMS ( 2007b). Gulf of Mexico sperm whales are classified as an endangered species and a " strategic stock " by NMFS (Waring et al., 2013). A " strategic stock " is defined by the MMPA as a marine mammal stock that meets the following criteria:

• T he level of direct human

- caused mortality exceeds the potential biological removal level;

• B ased on the best available scientific information, is in declin e and is likely to be listed as a threatened species under the ESA within the foreseeable future; or

• I s listed as a threatened or endangered species under the ESA, or is designated as depleted under the MMPA.

No critical habitat for the sperm whale has been designated in the Gulf of Mexico.

In 2013, NMFS conducted a status review to consider designating the Gulf of Mexico population of the sperm whale as a distinct population segment ( DPS ) under the ESA. The designation would list the Gulf of Mexico populat ion as a separate endangered or threatened population that is " significant to the species and faces additional unique threats to its survival. " On 13 November 2013, NMFS concluded that the designation of a Gulf of Mexico DPS for sperm whales is not warran ted (78 FR 68032).

The distribution of sperm whales in the Gulf of Mexico is correlated with mesoscale physical features such as eddies associated wi th the Loop Current (Jochens et al., 2008). Sperm whale populations in the north

- central Gulf of Mexico are present there throughout the year (Davis e t al., 2000). Results of a multi

- year tracking study show female sperm whales typically concentrated along the upper co ntinental slope between the 200

- and 1,000

- m (656

- and

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- ft) depth contours ( Jochens e t 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 (SW SS) consisted of mixed

- sex groups comprising adult females and immature whale s, and groups of bachelor males. Typical group size for mixed gro ups was 10 individuals (Jochens et al., 2008). A review of sighting reports from seismic mitigation surveys in t he Gulf of Mexico conducted over a 6

- year period found a mean group size for sperm whales of 2.5 individuals (Barkaszi et al., 2012). In these mitigation surveys, sperm whales were the most common cetacean encountered (Barkaszi et al., 2012). SWSS result s show that sperm whales transit through the vicinity of the lease area. Movements of satellite

- tracked individuals suggest that this area of the continental slope is within the home range of the Gulf of Me xico population (within the 95% uti lization distr ibution) (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 and a large oil spill. Effluent discharges ar e 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 potenti al for marine debris

- related impacts on sperm whales

.

C urrent threats to sperm whale populations worldwide are discussed in a final recovery plan for the sperm whale (NMFS, 2010 a ). 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 bas e due to climate change and ecosystem change, and cable laying. In the Gulf of Mexico , impacts from many of these threats are identified as either low or unknown ( BOEM, 2012 b )

. 

### Impacts of Drilling Rig Presence, Noise, and Lights

Noise generated from the d rilling rig and from routine drilling activities may be audible to sperm whales and so has the potential to disturb individuals near the lease area

. The drilling rig used during the proposed activity will be located within a deepwater, open ocean environm ent and will remain stationary during drilling operations. Sounds generated by the rig and by drilling operations will be generally continuous (with some variability in sound level, considering thruster activity)

. This analysis assumes that the continuou s nature of sounds produced by the drilling rig will provide individual whales with cues relative to the direction and relative distance (sound intensity) of the sound source, and the fixed position of the drilling rig will provide multiple options for act ive avoidance of potential physical impacts. 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 expected to produce amplitudes sufficient to cause hearing or behavioral effects in sperm whales; therefore, these effects are insignificant (NMFS, 2007 ).

In addition, there are other OCS faciliti es and activities near the lease area, and the region as a whole has a large number of similar noise sources. Drilling

- related noise associated with this project will contribute to an increase in the ambient noise environment of the Gulf of Mexico,

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- FINbut it is not expected in amplitudes sufficient to cause either hearing or behavioral effects to sperm whales.

Drilling rig lighting and rig presence are not identified as IPFs for sperm whales (MMS, 2007b ; BOEM, 2012a, b
, c , 2013 ; NMFS, 2007 )

. 

### 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 MMS ( 2007b). To reduce the potential for vessel strikes, BSEE and BOEM issued NTL 20 12

- JOINT

- G0 1 , 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 sight ed, 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 la rge 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 of disturbing sperm whales.

NMFS (2007) analyzed the potential for vessel strikes and h arassment of sperm whales . With implementation of the mitigation measures in NTL 20 12

- JOINT

- G01 , NMFS concluded that 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 cons equences at the population level

. With implementation of the vessel strike avoidance measures requirement to maintain a distance of 9 1 m ( 300 ft) from sperm whales, NMFS concluded that the potential for harassment of sperm whales would be reduced to disco untable levels.

Helicopter traffic also has the potential to disturb sperm whales. Smultea et al. (2008) documented responses of sperm whales offshore Hawaii to a 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 of 24 sightings (12%) . 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 the aircraft circled certain wh ales 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.

W hile fl ying 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 animal. Although respon ses are possible (Smultea et al., 2008), NMFS (2007) and BOEM (2012 d ) concluded that t his 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 sp erm whales
, are discussed in MMS ( 2007b ), NMFS ( 2007)

, and BOEM (2012a,b, c , 2013) . Oil impacts on marine mammals are discussed by Geraci and St. Aubin (1990). For this EP , there are no unique site

- specific issues wi th 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 Anadarko’ s preventative measures during routine operations
, including fuel transfer. In the unlikely event of a spill, implementation of Anadarko’ s OSRP could 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 s mall 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 oceanograp hic 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 more than 90% would evaporate or disperse naturally within 24 hours. The sea surface area 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 s kin, 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 s ( Marine Mammal Commission [ MMC ] , 2011 ). 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 are expected

. 

### Impacts of a Large Oil Spill
Potential spill impacts on marine mammals
, including sp erm whales
, are discussed in MMS ( 2007b ), NMFS (2007)

, and BOEM (2012a,b, c , 2013 )

. For this EP , 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, no ise, and dispersants) (MMC, 2011 ). Direct physical and physiological effects can include skin irritation, inflammation, or necrosis; chemical burns of skin, ey es, 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 s

. The level of impact of oil exposure depends on the amoun t, frequency, and duration of exposure; route of exposure; and type or condition of petroleum compounds or chemical dispersants (Waring et al., 2013). Complications of the above may lead to dysfunction of immune and reproductive systems, physiological str ess, declining physical condition, and death. Behavioral responses can include displacement of animals from prime habitat
, disruption of social structure
, changing prey availabil ity and foraging distribution or patterns , changing reproductive behavior/pro ductivity, and changing
movement patterns or migration (MMC, 2011 ). Ackleh et al. (2012) hypothesized that sperm whales may have temporarily relocated away from areas near the Macondo spill in 2010.

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- FINIn 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 or stress. Response vessels would operate in accorda nce with NTL 2012

- JOINT

- G01 to reduce the potential for striking or disturbing these animals.



### C. 3.2 West Indian Manatee (Endangered)

M ost of the Gulf of Mexico manatee population is located in peninsular Florida (USFWS, 2001). Manatee sightings in Louisia na have increased as the species extends its presence farther west of Florida in the warmer months (Wilson, 2003). A species description is presented in MMS ( 2007b) , BOEM (2013)

, and the recovery plan for this species (USFWS, 2001).

IPFs that could affect manatees include support vessel and helicopter traffic and a large oil spill. A small fuel spill in the lease area would be unlikely to affect manatees due to the distance from the nearest shoreline. As explained in Section A.9.2 , a small fuel spill wou ld not be expected to make landfall or reach coastal waters prior to natural dispersion

. 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 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, BSEE and BOEM issued NTL 20 12

- JO INT

- G0 1 , 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 si ghtings of any injured or dead protected species. Compliance with this NTL 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 s ; however, the helicopter was flown at relatively low altitude s 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. In addition, guidelines and regulations spec ify that helicopters maintain an altitude of 305 m ( 1,000 ft) within 91 m ( 300 ft) of marine mammals (BOEM, 2012a, b ). This mitigation measure will minimize the potential for disturbing manatees, and no significant impacts are expected.


### Impacts of a Large Oil Spill

In the event that manatees a re 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,

no ise, and dispersants) (MMC, 2011 ). Direct physica l 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 vegetation ; and stress from t he 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
, chang e in prey

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, chang e in reproductive behavior/productivity, and chang e in movement patterns or migration (MMC, 201 1 ).

In the event that a la rge spill reache s coastal waters where manatees a re 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 vessel s 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 s (blue whale, fin whale, humpback whale, North Atlantic right whale, and sei whale) 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.

Bec ause these whales rarely occur in the Gulf of Mexico and the limited sco pe and duration of the project, it is highly unlikely that any endangered mysticete would come into contact with project activities , either routine operations or accidents . NMFS did n ot include any of these mysticete s as affected species in its Biological Opinion (NMFS, 2007) . Potential impacts are analyzed in MMS ( 2007b ) and BOEM ( 2012a,b, c , 2013 )

, 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 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 a dditional species of marine mammals that may be found in the Gulf of Mexico
, includ ing 2 species of mysticete s , dwarf and pygmy sperm whales, 4 species of beaked whales, and 1 4 species of delphinids . All marine mammals are protected species under the MMPA

. 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 in the following subsections , and a dditional information o n these groups is presented in MMS ( 2007b) and BOEM (2012a,b, c , 2013)

. Mysticete W hale s . Two species of non

- endangered mysticete s are known to occur in 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 Py gmy 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 tropic al 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 ; Mullin, 2007; Waring et al., 2013 ). Either species could occur in the lease area.
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- sea identification, beaked whales in the Gulf of Mexico are identified either as C uvier’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 (Waring et al., 2013)

.

D elphinids . Fourteen species of delphinids are known to occur in the Gulf of Mexico : Atlantic spotted dolphin ( Stenella frontalis ), Clymene dolphin ( Stenella clymene ), p antropical spotted dolphin ( Stenella attenuata )

, s pinner dolphin ( Stenella longirostris ) , s triped dolphin ( Stenella coeruleoalba )

, bottlenose dolphin ( Tursiops truncatus ), f alse killer whale ( Pseudorca crassidens )

, k iller whale ( Orcinus orca )

, p ygmy killer whale ( Feresa attenuata )

, m elon

- headed whale ( Peponocephala electra ) , short

- finned pilot whale ( Globicephala macrorhynchus ) , R isso’s dolphin ( Grampus griseus )

, Fraser’s dolphin ( Lagenodelphis hosei ) , and r ough

- toothed dolphin ( Steno bredanensis )

. Any of these species could occur in the lease area (Waring et al., 2013)

. The most common non

- endangered cetaceans in the deepwater environment are the pantropical spotted dolphin, spinner dolphin, and Clymene dolphin.

Bottlenose D olphins

. The bottle nose dolphin ( Tursiops truncatus ) is a common inhabitant of the northern Gulf of Mexico, particularly within continental shelf waters. There are two ecotypes of bottlenose dolphins, a coastal form and an offshore form, which are genetically isolated from each other ( Waring et al., 2013 ). The offshore form of the bottlenose dolphin may occur within the lease area. Inshore populations of coastal b ottlenose dolphins in the northern Gulf of Mexico are separated into 37 geographically distinct population units, or stocks, for management purposes by NMFS (Waring et al.

, 201 3 ) . NMFS has proposed to classify the Gulf of Mexico Northern Coastal Stock, Western Coastal Stock, and all 32 of the Bay, Sound, and Estuarine Stocks as strategic stocks (Waring et al., 2013 ).

The strategic stock designation in this case was based primarily on the occurrence of an

" unusual mortality event " of unprecedented size and duration that has affected these stock

areas. The unusual mortality event began in February 2010 and, as o f June 201 4 , the event was still considered to be ongoing ( NOAA, 201 4 ; Waring et al., 2013). Carmichael et al. (2012) hypothesized that the unusual number of bottlenose dolphin strandings in the northern Gulf of Mexico during this time may have been assoc iated with environmental perturbations including sustained cold weather and the Macondo spill in 2010 as well as large volumes of cold freshwater discharge in the early months of 2011. Schwacke et al. (2014) reported that one year after the Macondo spill, many dolphins in Barataria Bay, Louisiana, showed evidence of disease conditions associated with petroleum exposure and toxicity.

IPFs that could affect non

- endangered marine mammals include drilling rig presence, noise, and lights; support vessel and hel icopter traffic ; and two types of accidents

– a small fuel spill and a large oil spill. Effluent discharges are likel y to have negligible impacts 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.

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### 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 generated durin g drilling operations is generally continuous and fixed in location. Noise intensity associated with these operations is relatively weak . Stronger noise levels will occur during thruster use in dynamic positioning. Thruster noise impacts would be expect ed at greater distances than vessel noi se alone (LGL Ecological Research Associates, Ltd.
, 2006) but are dependent on variables relating to thruster type and usage. It is expected that marine mammals within or near the lease area would be able to detect t he presence of the drilling rig and avoid exposure to higher energy sounds, particularly wit hin an open ocean environment.

Some odontocetes have shown increased feeding activity around lighted platforms at night (Todd et al

. , 2009). Even temporary drill in g rigs present an attraction to pelagic food sources that may attract both cetaceans and sea turtles. Therefore, prey congregation could pose an attraction to protected species that exposes them to higher levels or longer durations of noise that might oth erwise be avoided. There are other OCS facilities and activities near the lease

area , and the region as a whole has a large number of similar sources. Species in the northern Gulf of Mexico have been exposed to noise from anthropogenic sources for a long period of time and over large geographic areas and likely do not represent a naïve population with regard to sound (National Research Council, 2003b). Due to the limited duration of drilling activities
, this project would represent a temporary contributi on to the overall noise regime within the lease area, and potential impacts are expected to be biologically in significant to marine mammal populations.

Drilling rig lighting and rig presence are not identified as IPF s for marine mammals (MMS, 2007b, 2008 ; BOEM, 2012a,b , 2013 ).



### Impacts of Support Vessel and Helicopter Traffic
Support vessel traffic has the potential to disturb marine mammals
, and there is a risk of vessel strikes. Data concerning the frequency of vessel strikes are presented in MMS ( 2007b). To reduce the potential for vessel strikes, BSEE and BOEM issued NTL 20 12

- JOINT

- G0 1 , 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 v essel 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 a nd 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 t he 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 (W ü rsig et al., 1998). However, while flying offshore, helicopters maintain altitudes above 213 m (700 ft) during transit to and from the working area. In addition, guidelines and regulations specify that helicopters maintain

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### Impacts of a Small Fuel Spill
Potential spill impacts on marine mammals are discussed in MMS ( 2007b ) and BOEM ( 2012a,b
, 2013 )

. O il impacts on marine mammals in general are discussed by Geraci and St. Aubin (1990). For this EP , 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 Anadarko ’s preventative measures during routine operations, includ ing fuel transfer. In the unlikely event of a spill, implementation of Anadarko ’s OSRP is expected to lessen the potential for impacts on marine mammals.
EP Section H 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 a nd 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 more than 90% would evaporate or disperse naturally within 24 hours. The sea surfac e area 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; chemica l 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, 2011 ). 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 are expected

. 

### Impacts of a Large Oil Spill
Potential spill impacts on marine mammals are discussed in MMS ( 2007b ) and BOEM ( 2012a,b
, 2013 )

. For this EP , 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, 201 1 ). 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) direct ly or via contaminated prey (or contaminated vegetation, in the case of manatees); and stress from the activities and noise of response vessels and aircraft s . Complications of the above may lead to dysfunction of immune and reproductive systems, physiolog ical stress, declining physical condition, and death. Behavioral responses can include displacement of animals from prime habitat
, disruption of social structure
, chang e in prey availability and foraging distribution or patterns
, chang e in reproductive be havior/productivity, and chang e in movement patterns or migration (MMC, 201 1 ).

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- FINIn 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, en tanglement, 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)

F ive species of endangered or threatened sea turtles may be found near the lease area. Endangered species are the leatherback ( Dermochelys coriacea ), Kemp's ridley ( Lepidochelys kempii ), and hawksbill ( Eretmochelys imbricata ) turtles. In Sept ember 2011, NMFS and the USFWS listed nine DPS s for loggerhead turtles ( Caretta caretta ) under the ESA. The Northwest Atlantic Ocean DPS , which includes the Gulf of Mexico was designated as threatened ( 76 FR 58868 ) , although other DPSs are endangered. In March 2013, the USFWS proposed to designate critical habitat for this DPS including beaches in Jackson County, Mississippi; Baldwin County, Alabama; and Bay, Gulf, and Fr anklin Counties in the Florida
P anhandle, as well as several counties in southwest Florida and the Florida Keys (78 FR 18000). The green turtle ( Chelonia mydas ) is listed as threatened, except for the Florida breeding population, which is listed as endangered. Species descriptions are presented in BOEM (2012a, 2013).

Leatherback and lo ggerhead turtle s 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 near shore 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.

All five sea turtle species in the Gulf of Mexico are mig ratory and use different marine habitats according to their life stage. These habitats include high

- energy beaches for nesting females and emerging hatchlings and pelagic convergence zones for hatchling and juvenile turtles. As adults, green, hawksbill, and loggerhead turtles forage primarily in shallow, benthic habitats. Leatherback turtle s are the most pelagic of the sea turtles, feeding primarily on jellyfish.

Sea turtle nesting on the northern Gulf of Mexico coast can be summarized by species as foll ows:

• Loggerhead turtles

– Loggerhead turtles nest in significant numbers along the Florida Panhandle (Florida Fish and Wildlife Conservation Commission, 2014a ) and, to a lesser extent, from Texas through Alabama ( NMFS and USFWS, 2008 ). The nearest signifi cant 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

, 201 4b ,c );

• Kemp’s ridley turtles

– The main nesting site of Kemp’s ridle y turtles is Rancho Nuevo Beach in Tamaulipas, Mexico (NMFS et al., 2011). Approximately 150 Kemp’s ridley turtles nested on Texas beaches in 2013 (Sea Turtle Restoration Project, 20 13 ). Kemp’s ridley turtles typically do not nest anywhere near the project area, although there have been occasional reports of Kemp’s ridleys nesting in Alabama (Share the Beach, 201 4 ); and

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– Hawksbill turtles typically do not nest anyw here near the project area (USFWS, 2013)

.

IPFs that could affect sea turtles include drilling rig presence, noise, and lights; support vessel and helicopter traffic; and two types of accidents

– a small f uel spill and a large oil spill . 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

- relat ed 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 loggerhead turtle s, may be attracted to offshore structures (Lohoefener et al., 1990) and, thus, may be more sus ceptible to impacts from sounds produced during routine operations. 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 sho rt 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 t urtle hatchlings (Witherington, 1997; Tuxbury and Salm on, 2005). However, hatchlings may rely less on light cues when they are offshore than when they are emerging on the beach (S almon and Wyneken, 1990). NMFS (2007) concluded that the effects of lighting from offshore structures on sea turtles are insignif icant.


### Impacts of Support Vessel and Helicopter Traffic
Noise generated from s upport vessel traffic has the potential to disturb sea turtles
, and there is a risk of vessel strikes. Data show that vessel strike is one cause of sea turtle mortality in the G ulf of Me xico (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 pe riods of inclement weather. To reduce the potential for vessel strikes, BSEE and BOEM issued NTL 20 12

- JOINT

- G0 1 , 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 si ghted, 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).

Noise generated from support h elicopter 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 w ill 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 MMS ( 2007b ), NMFS ( 2007)

, and BOEM (2012a,b, 2013 )

. For this EP , there ar e no unique site

- specific issues with respect to spill impacts on these animals.

The probability of a fuel spill will be minimized by Anadarko’ s preventative measures during routine operations, includ ing fuel transfer. In the unlikely event of a spill, im plementation of Anadarko’ s OSRP is expected to minimize potential impacts on sea turtles. EP Section H 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 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 impa cts would depend on the meteorological and oceanographic conditions at the time of the spill, as well as the effectiveness of spill response measures. Section A.9.2 discusses the likely fate of a small fuel spill and indicates that more than 90% would eva porate or disperse naturally within 24 hours. The sea surface area 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 coul d 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 aircra ft s (MMS, 2007b; NMFS, 2010b; BOEM, 2012 a,b , 2013 )

. However, due to the limited areal extent and short duration of water quality impacts from a small fuel spill, no significant impacts are expected

. A small fuel spill in the lease area would be unlikely t o affect sea turtle nesting beaches due to the distance from 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 natural dispersion

. 

### Impacts of a Large Oil Spill
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 s kin 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 th e activities and noise of response vessels and aircraft s

. 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
, chang e in food availability and foraging d istribution or patterns , chang e in reproductive behavior/productivity, and chang e in movement patterns or migration (NOAA, 2010; NMFS, 2010 c )

. In the unlikely event of a spill, implementation of Anadarko’ s OSRP is expected to minimize the potential for these types of impacts on sea turtles. EP Section H provides detail on spill response measures.

Studies of oil effects on loggerhead turtle s in a c ontrolled setting (Lutcavage et al., 1995) suggest that sea turtles show no avoidance behavior when they encounter an oil slick
, and any sea turtle in an affected area would be expected to be exposed. Sea turtles’ diving behaviors also put

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The 30

- day OSRA results summarized in Table 3 estimate that Louisiana and Texas shorelines that support limited sea turtle nesting could be contacted within 30 days (1 % to 4 %). T he 120

- day OSRA ( Table 4 ) modeling predict s the probability of contacting Alabama and Florida Panhandle shorelines that support significant loggerhead sea turtle nesting is 1% or less.

Spilled oil reaching sea turtle nesting beaches could have e ffects 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 crawl s). 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 im paired 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 inj ury 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

. The extent and scope of the Macondo spill represents n ew information not assessed in the existing ESA Section 7 consultation under the current Five

- Year Program. As a result of this new information, BOEMRE reinitiated ESA Section 7 consultation on the existing Gulf of Mexico lease sale EIS with NMFS and the US FWS on 30 July 2010. NMFS responded with a letter to BOEMRE

on 24 September 2010 , and the US FWS responded with a letter to BOEMRE on 27 September 2010. However, NMFS and the US FWS have placed the consultation process on hold pending the results of the NRDA post

- Macondo spill data review, which has yet to be released. The existing consultation currently remain s in effect (BOEM, 2012b)

. Based on additional information and in consideration of the Macondo spill, BOEM (2012b) reexamined the i mpacts analys e s presented in MMS (2007b, 2008) for the five sea turtle species that inhabit the Gulf of Mexico based on additional information and in consideration of the Macondo spill. No new information was found that would alter the potential impact s o n sea turtles described in previous EISs . In most foreseeable cases, exposure to hydrocarbons persisting in the sea following the dispersal of an oil slick will res ult in sublethal impacts (e.g., decreased health, reproductive fitness, and longevity; and increased vulnerability to disease) to sea turtles.



### C.3. 6 Piping Plover (Threatened)

The p iping p lover ( 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 p lovers inhabit coastal sandy beaches and mudflats, feeding by probing for invertebrates at or just below the surface. They use beaches adjacent to

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. A large oil spill is the only IPF potentially affecting p iping p lovers. There are no IPFs associated with routine project activities that coul d 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 natural dispersion (see explanation in Section A.9.2 )

. 

### Impacts of a Large Oil Spill

The lease area is 122 miles ( 196 km ) from the nearest shoreline that is designed as critical h abitat for Piping Plovers ( Figure 3 ). The 120

- day OSRA results summarized in Section A.9.3 ( Table 4 ) predict that during the spring
, there is a 14% probability that an oil spill from the lease area would reach a shoreline designated as critical habitat for the Piping Plover within 1 2 0 days. Piping Plovers could ph ysically oil themselves while foraging on oiled shores or secondarily

c ontaminate themselves through ingestion of oiled intertidal sediments and prey (MMS, 2007b). Piping 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 activit ies associated with spill cleanup. Anadarko has extensive resources available to protect and rehabilitate wildlife in the event of a spill reaching the shoreline, as detailed in the OSRP.



### C.3. 7 Whooping Crane (Threatened)

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 [WCEP], 2013 ). One population winters along the Texas coast at Aransas NWR and summers at Wood Buffal o National Park in Canada. This population represents the majority of the world’s population of free

- ranging W hooping C ranes and reached a record population of 270 at Aransas NWR in December 2008 (WCEP, 2013 ). A non

- migrating population has been

re

- intro duced in central Florida, and another re

- introduced population summers in Wisconsin and migrates to the southeastern U.S. for the winter. Whooping C ranes 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). Approximately 9,000 ha (22,240 ac) of salt flats on Aransas NWR and adjacent islands make up the principal wintering grounds of the W hooping C rane . 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 W hooping C ranes

. A small fuel spill in the lease area would be unlikely to affect W hooping C ranes 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 natural dispersion

.

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- FINFigure 3. Location of selected environmental features in relation to the lease areas of interest. EFH = Essential Fish Ha bitat; HAPC = Habitat Area of Particular Concern; NMS= National Marine Sanctuary

.

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### Impacts of a Large Oil Spill

The lease area is 344 miles ( 553 km) from the nearest shoreline that is designed as critical habitat for Whooping Cranes ( Figure 3 ). The 120

- day OSRA results summarized in Section A.9.3 ( Table 4 ) predict that during the winter
, there is a 5% probability that an oil spill from the lease area would reach a shoreline designated as critical habitat for the Whooping Crane within
1 2 0 days

. Whooping C ranes could ph ysically oil themselves while foraging in oiled areas or secondarily contaminate themselves through ingestion of contaminated shellfish, frogs, and fishes (MMS, 2007b). It is possible that some deaths of Whooping Cranes could occur, especially if spills occur during winter months when Whooping Cranes are most common along the Texas
coast if the spill contact s their critical habitat in Aransas NWR

. Impacts could also occur from vehicular traffic on beaches and other activ ities associated with spill cleanup. Anadarko has extensive resources available to protect and rehabilitate wildlife in the event of a spill reaching the shoreline, as detailed in the OSRP.



### C.3. 8 Gulf Sturgeon (Threatened)

The Gulf sturgeon ( Acipenser oxy rinchus 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, Flo rida (Wakeford, 2001). T his range has contracted to encompass major rivers and inner shelf waters from the Mississippi River to the Suwannee River, F lorida. 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 Gul f 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 Choctawh atchee River in Alabama (Fox et al
., 2000), and the Pearl River in Mississi ppi/Louisiana (Morrow et al., 1998). Critical habitat in the Gulf extends from Lake Borgne, Louisiana (St. Bernard Parish) t o Suwannee Sound, Florida (Levy County) (NMFS, 2010 b ) ( Figure 3 )

. A species description is presented in MMS ( 2007b) and in the rec overy plan for this species (USFWS et al., 1995)

. A large oil spill is the only IPF that could affect 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 natural dispersion (see explanation in Section A.9.2 )

. 

### Impacts of a Large Oil Spill
Potential spill impacts on Gulf sturgeon are discussed in MMS ( 2007b ), NMFS (2007) , and BOEM (2012a,b, 2013)

. For this EP , there are no unique site

- specific issues with respect to this species.

The lease area is approximately 232 miles ( 374 km) from the nearest Gulf sturgeon critical habitat. The 120

- day OSRA modeling (BOEM, 2012b) predicts tha t a spill in the lease area has 1% or less probability of contacting any coastal areas inhabited by Gulf sturgeon within 120 days.

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- adult and adult Gulf sturgeon would b e most vulnerable to an estuarine or marine oil spill, and likely would be vulnerable only from
1 September through 30 April when the species is foraging in estuarine and shallow marine habitats (NMFS, 2007).



### C.3. 9 Beach Mice (Endangered)

Four subspecies of endangered beach mice ( Peromyscus polionotus ) occur on the barrier islands of Alabama and the Florida Panhandle : the Alabama, Choctaw h atchee, Perdido Key, and St. Andrew beach mice. Critical habitat has been designated for all four subspecies ; Figure 3 shows the combined critical habitat for all four subspecies . Species descriptions are provided in MMS ( 2007b) and BOEM (2013)

. A large oil spill is the only IPF that could affect 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 e xpected to make landfall or reach coastal waters prior to natural dispersion (see Section A.9.2 )

. 

### Impacts of a Large Oil Spill
Potential spill impacts on beach mice are discussed in MMS ( 2007b, 2008 ) and BOEM ( 2012a
, 2013 ). For this EP , there are no uniqu e site

- specific issues with respect to these species that were not analyzed in these documents

.

B each mouse critical habitat is 271 miles ( 436 km) from the lease area. The 120

- day OSRA modeling summarized in Section A.9.3 predicts that a spill in the lease area has a 1% or lower 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 indir ect 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 to xicity 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.3.10 S malltooth S awfish (Endangered)

Smalltooth sawfish ( Pristis pectinata ) are found in the tropical and subtropical Atlantic Ocean. In the W estern Atlantic
, they have historically ranged from New York to Brazil, including the Gulf of Mexico and Caribbean Sea. Smalltooth sawfish primarily occur in estuarine and coastal habita ts 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 c oastal habitat, and the Ten Thousand Islands/Everglades Unit, which comprises approximately 250,506 ha ( 619,013 ac )

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- FINof coastal habitat. The two units are located along the southwestern coast of Florida between Charlotte Harbor and Florida Bay.

A large oil spill 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 smal l fuel spill would not be expected to make landfall or reach coastal waters prior to natural dispersion (see Section A.9.2 )

.



### Im pacts of a Large Oil Spill
Potential spill impacts on smalltooth sawfish are similar to those discussed for other coastal and estuarine species in MMS ( 2007b ), NMFS (2007 ), and BOEM (2012a, 2013 )

. For this EP , there are no unique site

- specific issues with respect to smalltooth sawfish

. 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 petrole um products through the gills.



### C.3. 11 Elkhorn Coral ( Threatened )

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 of Mexico
, e lkhorn coral has been found within the coral cap region of the Flower Garden Banks National Marine Sanctuary ( Flower Garden Banks National Marine Sanctuary [ NMS ]
, 2014 ). The nearest critical habitat is designated in the Florida Keys.

NMFS has recently proposed to change the designation of elkhorn coral and staghorn coral ( Acropora cervicornis ) from threatened to endangered (77 FR 73220). Five other Atlantic corals are proposed for endangered listing: pillar coral ( Dendrogyra cylindrus ), b oulder star coral ( Mont astraea annularis ), mountainous star coral ( Montastraea faveolata ), cactus coral ( Mycetophyllia ferox ), and star coral ( Montastraea franksi ). Two Atlantic species, Lamarck's sheet coral ( Agaricia lamarcki ) and elliptical star coral ( Dichocoenia stokesii ), are proposed for listing as a threatened species . None of these species other than elkhorn coral are reported to occur in the northern Gulf of Mexico ( Flower Garden Banks NMS, 2014 ) and the nearest populations ar e in the Florida Keys.

There are no IPFs associated with routine project activities that could affect this species in the northern Gulf of Mexico

. A small fuel spill would not affect elkhorn coral colonies because the oil would float and dissipate on the sea surface. Thus, a l arge oil spill is the only relevant IPF.


### Impacts of a Large Oil Spill
A large oil spill would be unlikely to reach elkhorn coral critical habitat in the Florida Keys (Monroe County, Florida) or coral reefs at the Flower Garden Banks. The 120

- day OSRA mode ling ( Table 4 ) predicts the probability of contacting the Florida Keys is 1% or lower

. A spill would be highly unlikely to reach the Flower Garden Banks. A surface slick would not contact corals on the seafloor. If a subsurface plume were to occur, impa cts on the banks would be unlikely due to the distance and the difference in water depth. Near

- bottom currents in the

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## 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 shorebird s may occasionally be present over open ocean ar eas. No endangered or threatened bird species are likely to occur at the project area due to the distance from shore. For a discussion of shorebird s and coastal nesting birds, see Section C.4.2

. Seabirds of the northern Gulf of Mexico were surveye d 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, f our ecological categories of seabirds were docum ented in the deepwater areas of the Gulf: summ er 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). The GulfCet II study did not estimate bird densities; however, Powers (1987) indicate d that seabird densitie s over the open ocean typically are <10 birds/km 2

. The distributions and relative densities of seabirds within the deepwater areas of the Gulf of Mexic o, including the project area, vary temporally (i.e., seasona lly) and spatially. In GulfCet II studies, species diversity and densit y varied by hydrographic environment and by the presence and relative location of mesoscale features such as Loop Current eddies that may enhance nutrient levels and productivity of surface waters where these seabird species for age ( Hess and Ribic
, 2000 )

.

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 inc lement 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 that could affect 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. Effluent discharges are likely to have negligible impacts on the birds due to rapid dispersion, the small area of ocean affected, th e intermittent nature of the discharges, and the 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 r ig s 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, resulti ng 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
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. In other cases, navigation may be disrupted by noise (Russell, 2005). However , 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 EP, any impacts on populations of either seabirds or trans

- Gulf migrant birds from activiti es described in this EP are not expected to be significant.



### 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 wo uld 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 MMS ( 2007b ) and BOEM ( 2012 a,b
, c , 2013 )

. F or th e EP , there are n o unique site

- specific issues with respect to spill impacts on these animals.

The probability of a fuel spill will be minimized by Anadarko ’s preventative measures during routine operations
, including fuel transfer. In the unlikely event of a spill, imple mentation of Anadarko ’s OSRP could reduce the potential for impacts on marine and pelagic birds.
EP Section H 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 exte nt 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 more than 90% woul d evaporate or disperse naturally within 24 hours. The sea surface area 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 phys ical 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 imp acts 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 are expected

. 

### Impacts of a Large Oil Spill
Potential spill impacts on marine and pelagic birds are discussed in MMS ( 2007b ) and BOEM ( 2012a,b
, c , 2013 )

. For this EP , there are no unique site

- specific issues with respect to spill impacts on these ani mals.

BOEM has reexamined the analys e s for coastal and marine birds presented in MMS (2007b, 2008) and determined that no new information was found that would alter the potential impact s on marine and pelagic birds ( BOEM, 2012 b ).

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- FINPelagic seabirds could be exposed to oil from a spill at the project area. Hess and Ribic (2 000) reported that terns, storm

- petrels, shearwaters, and jaegers were the most frequently sighted seabirds in the deepwater Gulf of Mexico (>200 m [> 656 ft] ). Po wers (1987) indicate d that seabird densities over the open ocean typically are <10 birds/km 2 . The number of pelagic birds that could be affected in open offshore waters would depend on the extent and persistence of the oil slick.

Data following t he Macond o spill provide 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, a nd Masked Booby ( USFWS, 2011 ). The Northern Gannet is among the species with the largest numbers of birds affected by the spill.



### C. 4.2 Shorebird s and Coastal Nesting Birds

Threatened and endangered bird species (Piping Plover and Whooping Crane) have been discussed previously in Section s C.3 .6 and C.3.7 . Various species of non

- endangered birds are also found along the northern Gulf C oast, including diving birds, shorebird s, 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, Wil son’s Plover, Black Skimmer, Forster’s Tern, Gull

- Billed Tern, Laughing Gull, Least Tern, and Royal Tern (USFWS, 2010b). Additional information is presented in MMS ( 2007b ) and BOEM ( 2012a , 2013 ).

The Brown Pelican ( Pelecanus occidentalis ) was delisted fro m Fe deral endangered status in 2009 (USFWS, 2010c). However, this species remains on the Louisiana list of Endangered Species ( State of Louisiana Department of Wildlife and Fisheries, 2013), is listed as a species of greatest conservation need by the Stat e of Mississippi (Mississippi Department of Wildlife, Fisheries and Parks, 20 05 )

, and is listed a s a species of special concern by the State of Florida (Florida Fish and Wildlife Conservation Commission, 201 4 d ). Brown Pelicans inhabit coastal habitats and forage within both coastal 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 (Fri tts and Reynolds, 1981; Peake, 1996; Hess and Ribic, 2000). Nearly half the southeastern population of Brown Pelicans live s in the northern Gulf Coast, generally nesting on protected islands (USFWS, 2010 b ).

The Southern Bald Eagle ( Haliaeetus leucocephalu s ) 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 C oast is inhabited by bot h wintering migrant and resident Bald Eagl es (Johnsgard, 1990; Ehrlich
et al., 1992).

IPFs that could affect shorebird s and coastal nesting birds include support vessel and helicopter traffic and a large oil spill. A small fuel spill in the lease area wou ld be unlikely to affect shorebird s or coastal nesting birds , due to the lease area’s distance 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 natural di spersion

. Compliance with NTL 2012

- BSEE

- G01 will minimize the potential for marine debris

- related impacts on shorebirds.

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### Impacts of Support Vessel and Helicopter Traffic
Support vessels and helicopters will transit coastal areas near Port Fourchon and Houma, Louisiana, where shorebirds and coastal nesting birds may be found. These activities could periodically disturb individuals or groups of birds within sensitive c oastal habitats (e.g., wetlands that may support feeding, resting, or breeding bir ds).

Vessel traffic may disturb foraging and resting birds. Flushing distances vary among species and individuals (Rodgers and Schwikert, 2002). The disturbances will be limited to flushing birds away from vessel pathways; kn own distances are from 20 to 49 m (65 to 160 ft) for personal watercraft s and 23 to 58 m (75 to 190 ft) for outboard

- powered boat s (Rodgers and Schwikert, 2002). Flushing distances may be similar or less for the support vessels to be used for Anadarko ’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 are 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.

Aircraf t traffic can cause some disturbance to birds onshore and offshore. Responses are highly dependent on the type of aircraft, bird species, 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 61 0 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.


### Impacts of Large Oil Spill
Coastal birds can be exposed to oil as they float on the water 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, 2010 d ). Oil interferes with the water repellen cy 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 a nd 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 previously , the Brown Pelican was recently removed from the Federal endangered species list. Brown Pelicans are especially at risk from direct and indirect impacts from spilled oil within inner shelf and inshore waters, such as embayments . The range of this specie s is generally limited to these waters and surrounding coastal habitats. Brown Pelicans feed on mid

- size fish that they capture by diving from above ( " plunge diving " ) and then scooping the fish into their expandable gular pouch. This behavior makes them susceptible to plumage oiling if they feed in areas with surface oil or an oil sheen. They may also capture prey that has been physically contaminated with oil or has ingested oil. Issues for Brown Pelicans include direct

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- term habitat contamination. The Bald Eagle also may be at risk from direct and indirect impacts from spilled oil. This species often captures fish within shallow water areas (snatching prey from the surface or wading into shallow areas to capture prey with their bill) and so may be susceptible to plumag e oiling and, as with the Brown Pelican , they may also capture prey that has been physically contaminated with oil or has ingested oil.



## 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, the surface waters of which 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 w aters 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 speci es) (MMS, 2007b). A study by Ross et al. (2012) on midwater fauna to characterize vertical distribution of mesopelagic fishes in selected deepwater areas in the Gulf of Mexico substantiated high species richness but general domination by relatively few fa milies and species.

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.


### Impacts of D rilling Rig Presence, Noise, and Lights
The drilling rig, as a floating structure in the deepwater environment, will act as a fish aggregating 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 (Holland et al., 1990; Higashi, 1994; Reli ni et al., 1994 ; MMS, 2000, 2007b, 2008 ). The 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 populatio ns, 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 dilute rapidly to undetectable levels within tens to hundreds of meters from the source. Minimal impacts on water quality, plankton, and nekton are anticipated.

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- FINDeck 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 dilute 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 wi th the NPDES permit, such as desalination unit brine and uncontaminated cooling water, fire water, and ballast water
, are expected to dilute rapidly and have little or no impact on water column biota.


### Impacts of Water Intakes

Seawater will be drawn from th e ocean for once

- through, non

- contact cooling of machinery

on the drilling rig. The drilling rig ultimately chosen for this project will be in compliance with all cooling water intake requirements. T he intake of seawater for cooling water will entrain pl ankton. 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. Th e entrained organisms may be stressed or killed, primarily through changes in water temperature during the route from cooling intake structure to discharge structure and through mechanical damage (turbulence in pumps and co ndensers). 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 resource s are discussed in MMS ( 2007b ) and BOEM ( 2012a, b
, 2013 )

. F or this EP , there are no unique site

- specific issues with respect to spill impacts.

The probability of a fuel spill will be minimized by Anadarko’ s preventative measures during routine operations including fuel transfer. In the unlikely event of a spill, implementation of Anadarko ’s OSRP could mitigate the potential for impacts on pelagic communities, including ichthyoplankton. EP Section H provid es 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 more than 90% would evaporate or disperse naturally within 24 hours. The sea surface area with diesel fuel on it would range from 0.5 to 5 ha (1.2 to 12 ac)

, depending on se a state and weather conditions.

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- FINA 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
Potential spill impacts on pelagic communities and ichthyoplankton are discussed in BOEM ( 2012 a, b
, c , 2013 ). For this EP , there are no unique site

- specific issues.

A large oil spill co uld 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 . Fish e ggs and larvae 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 c ould be greater if local

- scale currents retained planktonic larval assemblages (and the floating oil slick) within the
same water mass.



### C. 5.2 Essential Fish Habitat

Essential Fish Habitat (EFH) is defined as th e waters and substrate necessary t o fish for spawning, breeding, feeding, and growth t o 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 Mana gement Plans developed by the regional Fishery Management Councils.

BOEM (201 2 b ) has reexamined the analysis for fish resources and EFH presented in MMS ( 2007a,b) in consideration of the Macondo event. No substantial new information was found that would a lter the impact conclusions for fish resources and EFH presented in MMS (2007a,b)

. The Gulf of Mexico Fishery Management Council (GMFMC) has prepared Fishery Management Plans for corals and coral reefs, shrimp s , 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). T he EFH for most of these GMFMC

- manag ed 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 featu res located approximately 88 miles ( 142 km) north west of the lease area

. 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 in or near the lease area include the following species and life stages (NMFS, 2009):

• Atlantic bluefin tuna (spawn, eggs, larvae, adults)

• Bigeye thresher shark (all)

• Bigeye tuna ( juveniles, adults) • Blue marlin (juveni les, adults)

• Longfin spearfish (juveniles, adults)

• Longfin mako shark (all)

• Oceanic whitetip shark (all)

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• Silky shark (all)

• Skipjack tuna (spawn , adults )

• Swordfish (larvae, juveniles , adults )

• Tiger shark (adults) • Whale shark (all)

• White marlin (juveniles, adults)

• Yellowfin tuna (spawn, juveniles, adults)

R esearch indicates the central and western Gulf of Mexico may be important spawning habitat for Atlantic bluefin tuna ( Thunnus thynnus ) , 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 300,000 km 2 (1 1 5, 830 mi 2 )

. The prevailing a ssumption 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 Apr il, May, and June (NMFS, 2009).

On 27 May 2011, after an e xtensive scientific review, NOAA announced that Atlantic bluefin tuna currently do not warrant species protection under the ESA

. However, NOAA did classify the bluefin tuna as a species of concern, effectively placing the species on a watch list as the agency awaits new data on the impact of a stricter international management regimen

.

An amendment to the original EFH Generic Amendment was finalized in 2005 (GMFMC, 2005). One of the most significant proposed changes in this amendm ent 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 Economic Zone ( EEZ )

. The Highly Migratory Species Fisheries Mana gement Plan was amended in 2009 to update
EFH and HAPC to include the bluefin tuna spawning area ( NMFS , 2009).

NT Ls 2009

- G39 and 2009

- G40 provide guidance and clarification of regulations for biologically sensitive underwater features and areas and benthic communities that are considered EFH (MMS, 2009 a,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 pl ace, the 1999 Programmatic Consultation with the elements described previously will be followed ( BOEM, 2012 b ).

Other HAPCs have been identified by the GMFMC (2005). These include the Florida Middle Grounds, Madison

- Swanson Marine Reserve, Tortugas North a nd South Ecological Reserves, Pulley Ridge, and several individual reefs and banks of the northwestern Gulf of Mexico ( Figure 3 ). The nearest HAPC is the Jakkula Bank
, located approximately 62 miles ( 9 9 km) from the project area

.

IPFs that could affect 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.


### Impacts of Drilling Rig Presence, Noise, and Lights
The drilling rig, as a floating structure i n the deepwater environment, will act as a n 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 ). The FAD effect would possibly enhance feeding of epipelagic predators by attracting and

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### 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 migrato ry 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 sho rt 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
Potential spill impacts on EFH are discussed in MMS ( 2007b ) and BOEM (2012a ,b
, c , 2013 ). For this EP , there are no unique site

- specific issues with respect to spill impacts.

The probability of a fuel spill will be minimized by Anadarko ’s preventative measures during routine operations
, including fuel transfer. In the unlikely event of a spill, implementation of Anadarko ’s OSRP could help diminish the potential for impacts on EFH. EP Section H 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 produc ts. 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 more than 90% would evaporate or disperse naturally within 24 hours. The sea surface area 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 bluefin tuna, which cov ers much of the deepwater Gulf of Mexico. The affected area would represent a negligible portion of the HAPC, which covers approximately 115,830 mi 2 (300,000 km 2 ) of the Gulf of Mexico.

A small fuel spill would likely not affect EFH for corals and coral r eefs, the nearest of which is located approximately 88 miles ( 142 km) from the project area

. A small fuel spill would float and dissipate on the sea surface and would not contact these features.


### Impacts of a Large Oil Spill
Potential spill impacts on EFH are discussed in MMS ( 2007b ) and BOEM ( 2012a, b , 2013 ). For this EP , there are no unique site

- specific issues with respect to EFH.

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w ater 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 sh rimp s , 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 contamin ated and result in persistent degradation of the seafloor habitat for managed demersal fish and shellfish species.

T he lease area is within the HAPC for spawning Atlantic bluefin tuna (NMFS, 2009). A large spill could temporarily degrade the HAPC due to i ncreased hydrocarbon concentrations in the water column, with the potential for lethal or sublethal impacts on spawning tuna. Potential impacts would depend in part o n the timing of a spill, as the species migrates to the Gulf of Mexico to spawn in April, May, and June (NMFS, 2009).

The topographic features located 88 miles ( 142 km) from 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, because a surface slick would not reach these features due to their depth

.


## C. 6 Archaeological Resources

C. 6.1 Shipwreck Sites

The lease area is not on the list of OCS blocks with a high potential for historic shipwrecks (BOEM, 2012d )

. Numerous sonar contacts were noted during the archaeological survey ( Fugro GeoServices, Inc.
, 20 0 3 ), but none were interpreted to be shipwrecks

. Anadarko will abide by the applicable requirements of NTL 2005

- G07, which stipulate that work be stopped at the project site if any previously undetected archaeological resource is discovered after work has begun until appropriate surveys and evaluations have been completed.

Because there are no known shipwreck sites in the lease area, there are no routine IPFs that are likely to a ffect shipwrecks. I mpacts of a large oil spill 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
MMS (2007b) estimate d 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 approximately 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 resul ted from the use of subsea 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

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, depending on its extent, trajectory, and persistence (Spier et al., 2013)

. If oil from a subsea spill should come into contact with wooden shipwrecks on the seafloor
, it could adversely affect their condition or pres ervation. Should there be any indication that potential shipwreck sites could be affected, in accordance with NTL 2005

- G07
, Anadarko will immediately halt operations, take steps to ensure that the site is not disturbed in any way
, and contact the BOEM Reg ional Supervisor, Leasing and Environment, within 48 hours of its discovery. Anadarko would cease all operations within 305 m (1,000 ft) of the site until the Regional Supervisor provides instructions on steps to take to assess the site’s potential histor ic significance and protect it.

A spill entering shallow coastal waters could conceivably contaminate an undiscovered shipwreck site. A s noted by MMS (2007b), should an oil spill contact a coastal historic site, such as a fort or a lighthouse, the major i mpact 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 9 1 m ( 300 ft), and possibly as much as 130 m (427 ft), lower than present sea level during the period 20,000 to 17,000 years b efore p resent (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 above sea level, the area was open to habitation by prehistoric peoples. The advent of early man into t he Gulf of Mexico region is currently accepted to be approximately 12,000 years B.P. (Aten, 1983). The sea

- level curve for the northern Gulf of Mexico proposed by Coastal Environments, Inc. suggests that sea level 12,000 years B.P. would have been approxi mately 45 to 60 m (148 to 197 ft) bel ow present

- day sea level ( Coastal Environments, Inc.
, 1977
, 1982). On this basis, the contine ntal shelf shoreward of the 45

- to 60

- m (148

- to 197

- ft) bathymetric contours has potential for prehistoric sites dating afte r 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, MMS adopted the 60

- m (197

- ft) water depth as the seaward extent for archaeological site potential in the Gulf of Mexico region

.
With water depths rangin g from approximately 1,573 to 1,695 m ( 5,160 to 5,560 ft)

, the project area is well beyond the 60

- m (197

- ft) depth contour used by BOEM as the seaward extent for prehistoric archaeological site potential in the Gulf of Mexico

. Numerous sonar contacts were identified d uring the archaeological survey conducted by Fugro GeoServices, Inc. ( 2013 ) , but none were interpreted to be shipwrecks or of archeologic al significance

. B ecause prehistoric archaeological sites are not found in the lease area, the only relevant IPF is a large oil spill.
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
Because prehistoric archaeological sites are not found in the lease area, they would not be impa cted by the physical effects of a subsea blowout. MMS (2007b) estimate d that a severe subsurface blowout could re suspend and disperse sediments within a 300

- m (984

- ft) radius.

Along the northern Gulf C oast, 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

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, 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 o iled sample for radiocarbon dating). Coastal prehistoric sites also could be damaged by spill cleanup operations (e.g., by destroying fragile artifacts and disturbing the provenance of artifacts and site features).



## 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 MMS ( 2007b ) and BOEM ( 2012a,b, c , 2013 )

, and are tabulated in the OSRP

. Coastal habitats inshore of the project area include barrier beache s and dunes, wetlands, and submerged seagrass beds. M ost of the northeastern Gulf is fringed by barr ier beaches, with wetlands and submerged seagrass beds occurring in sheltered areas behind the barrier islands and in estuaries.

Due to the distance from s hore, the only IPF associated with routine activities in the lease area that could affect beaches and dunes, wetlands, seagrass beds, coastal wildlife refuges, wilderness areas, or any other managed or protected coastal area relate to support vessel traffi c. The support bases at Port Fourchon and Houma, Louisiana
, are not in wildlife refuge s or wilderness area s . Potential impacts of support vessel traffic are briefly addressed below.

A small fuel spill in the lease area would be unlikely to affect coastal habitats due to the lease area’s distance from the nearest shoreline

. A s explained in Section A.9.2 , a small fuel spill would not be expected to make landfall or reach coastal waters prior to natural dispersion

. 

### 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 EP Section K
, 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
Potential spill impacts on coastal habitats are discussed in MMS ( 2007b ) and BOEM ( 2012a,b, c , 2013 ). Coastal habitats inshore of the project area include barrier beaches and dunes, wetlands, and submerged seagrass be ds. For this EP , there are no unique site

- specific issues with respect to coastal habitats.

The 30

- day OSRA modeling ( Table 3 ) indicates that Calhoun, Texas is the area most likely to be contacted in the event of a spill in the lease area. However, the 1 20

- day OSRA modeling summarized in Table 4 predicts potential shoreline contacts ranging from Camer on County, Texas
, to Miami

- Dade C ounty, Florida
, within 120 days.

The shorelines within the geographic range predicted by the 120

- day OSRA modeling ( Table 4 ) 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 MMS ( 2007b ), BOEM ( 2012b )

, and Anadarko’ s OSRP. Coastal and near coastal wildlife refuges, wilderness areas , and state and n ational parks within the geographic range of the potential shoreline contacts after 30 days are presented in Table 7

.

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. W ildlife refuges, wilderness areas
, and s tate and n ational parks within the geographic range of the potential shoreline contacts after 30 days based on OSRA modeling.

County or Parish, State W ildlife Refuge, Wilderness Area, or State/National Park

Terrebonne, Louisiana Atchafalaya Delta WMA Mandalay NWR Isles Dernieres Barrier Islands Refuge
Point Au Chein WMA

Lafourche, Louisiana Point Au Chein WMA
Wisner WMA

Plaquemines, Louisiana Salvador WMA Jean Lafitte National Historical Park and Preserve
Delta NWR
Pass A Loutre WMA
Breton NWR
St. Bernard State Park

Iberia , Louisiana Marsh Island WMA Cypremort Point State Park Shell Keys NWR

Vermillion
, Louisiana Rockefeller WMA Paul J. Rainey WMA

Cameron, Louisiana Sabine NWR
Cameron Prairie NWR
Lacassine NWR
Little Pecan Island Preserve Peveto Woods Bird Sanctuary
Lower Neches WMA

Rockefeller WMA

Jefferson, Texas McFaddin NWR
Sea Rim State Park
Texas Point NWR Murphree WMA

Galveston, Texas Brazoria NWR
Galveston Island State Park Apfell Park
Seawolf Park
Old Fort Travis Park
Atkinson Island WMA
Ft. Anahuc Park
Anahuc NWR
McFaddin NWR Candy Abshier WMA
Atkinson Island WMA

Brazoria, Texas San Bernard NWR
Peach Point WMA

Brazoria NWR Christmas Bay State Park Christmas Bay Coastal Preserve

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County or Parish, State W ildlife Refuge, Wilderness Area, or State/National Park

Matagorda, Texas Aransas NWR
Mad Island WMA Big Boggy NWR
San Bernard NWR

Calhoun, Texas Mission

- Aransas National Estuarine Research Reserve
Aransas NWR Matagorda Island State Park

Guadalupe Delta WMA
Welder Flats Coastal Reserve

NWR = National Wildlife Refuge; WMA = Wildlife Management Area

.

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 v arying 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. MMS (200 7b) 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. Approximately 15% of the contacted wetlands are expected to be converted permanently to open

- water habitat. The criti cal concentration of oil is the concentration above which impacts to wetlands will be long

- term and recovery will take longer than two growing seasons, and which causes plant mortality and some permanent wetland loss. Critic al 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 a ddition 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, 2012b ).



## 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 spill.
N o new information was found that would alter the potential impact s on commercial fishing ( BOEM, 2012 b , 2013 )

.

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summer

. 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 inte rvals. It takes 8 to 10 hours to deploy a longline and approximately the same time to retrieve it. Longlines are often set near oceanographic features such as fronts or downwellings, w ith the aid of sophisticated on board temperature sensors, depth finder s, and positioning equipment. Vessels typically are 10 to 30 m (33 to 98 ft) long, and their trips last from 1 to 3 weeks. The main Gulf of Mexico homeports for longlining vessels are in Louisiana (Dulac and Venice) and Florida (Destin, Madeira Beach, an d Panama City).

It is unlikely that any commercial fishing activity other than longlining will occur in 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 approximately 250 to 550 m (820 to 1,804 ft). Tilefish es (primarily Lophalotilus chamaeleonticeps ) are caught by bottom longlining in water depths from approximately 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
recreat ional fishers would be petroleum rig s 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 pres ence (including noise and lights)

. T wo types of potential accidents are also addressed

– a small fuel spill and a large oil spill.


### Impacts of Drilling Rig Presence , Noise, and Lights
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 inciden t. 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 intermitten t nature of the discharges.



### Impacts of a Small Fuel Spill
The probability of a fuel spill will be minimized by Anadarko’s preventative measures during routine operations including fuel transfer. In the unlikely event of a spill, implementation of Anadarko ’s OSRP could potentially mitigate and reduce the potential for impacts

. EP Section H

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Pelagic longlining activities in the lease area, if any, could be interrupted in the event of a small fuel spill. The sea surface area 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 becau se the spill would not be expected to make landfall or reach coastal waters prior to natural dispersion (see Section A.9.2 ).



### Impacts of a Large Oil Spill
Potential spill impacts on fishing activities are discussed in MMS ( 2007b ) and BOEM ( 2012 a,b
, 2013 ). For this EP , 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. Data following t he Macondo spill provide information ab out the maximum potential extent of fishery closures in the event of a large oil spill in the Gulf of Mexico (NMFS, 2010 d ). At its peak on 12 July 2010, closures encompassed 217,821 km 2 (84,101 mi 2 ), or 34.8% of the U.S. Gulf of Mexico EEZ.



### C. 8.2 Public H ealth 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 are addressed in the following subsections

. 

### Impacts of a Small Fuel Spill
The p robability of a fuel spill will be minimized by Anadarko ’s preventative measures during routine operations including fuel transfer. In the unlikely event of a spill, implementation of Anadarko ’s OSRP could potentially alleviate the potential for impacts

. EP Section H provide s 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 122 miles ( 196 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 natural dispersion (see Section A.9.2 ).



### Impacts of a Large Oil Spill
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 resp onding to the spill. The drilling rig maintains a Shipboard Oil Pollution Emergency Plan as required under MARPOL 73/78.

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- FINDepending on the spill rate and duration, the physical/chemical characteristics of the oil, meteorological and oceanographic condition s 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 cr ude oil fire can cause irritation, and in large quantities may pose a health hazard.

Data from the 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 reported by so me wildlife

- cleaning workers as well . Personnel working on offshore vessels or providing direct oversight to o ffshore vessels, including USCG personnel, civilian contractors, and other responders who were exposed to oil and dispersants
, had a 7 to 12 time s 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 humi d environment. Initial symptoms from cleanup workers who sought medical care in Louisiana were typical of acute exposure to hydrocarbons or H 2 S ( 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 off shore 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 are addressed in the following subsections

. 

### Impacts of a Small F uel Spill
The probability of a fuel spill will be minimized by Anadarko ’s preventative measures during routine operations including fuel transfer. In the unlikely event of a spill, implementation of Anadarko ’s OSRP could potentially mitigate and reduce th e potential for impacts. EP Section H provide s 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 dissipat ed 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
Potential socioeconomic impacts of an oil spill are discussed in MMS ( 2007b ) and BOEM ( 2012a,b
, c , 2013 ). For this EP , 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 par t of the response effort; it could result in adverse publicity that

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In addition to the analys e s presented in MMS (2007b, 2008 ) and BOEM (201 2 b ), a study explored the economic impacts of the Macondo spill on oil and gas industry employment due to suspension of deepwater drilling (Inter

- Age ncy Economic Report, 2010). The study indicates that during the moratorium, the number of oil industry workers in the Gulf of Mexico fell by approximately 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 6

- month period; this direct reduction in spending affected employment in the industries that supply the Gulf drilling industry and in all other industries affected b y declines in consumer and business spending (Inter

- Agency Economic Report, 2010)

.


### C. 8.4 Recreation and Tourism

BOEM has reexamined the analys e s for recreation and tourism presented in MMS (2007b, 2008) based on additional information and in consideration of the Macondo oil spill event. N o new information was found that would alter the potential impact s on recreation and tourism ( BOEM, 2012 b , 2013 ).

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 Anadarko ’s preventative measures during routine operations including fuel transfer. In the unlikely event of a spill, implementation of Anadarko ’s OSRP could potentially help mitigate and reduce the potential for impacts.
EP Section H 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 br ief.

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 natural dispersion

. 

### Impacts of a Large Oil Spill
Potential impacts of an oil spill on recreation and tourism are discussed in MMS ( 2007b ) and BOEM ( 2012a ,b, c , 2013 ). For this EP , there are no unique site

- spe cific 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 co ntaminating beaches and wetlands, resulting in negative publicity that encourages people to stay away. The 30

- day OSRA modeling summarized in Table 3 indicates that Cameron
, Louisiana is the area most likely to be contacted in the event of a spill in the project area. However, t he 120

- day OSRA model predicts

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, to Miami

- Dade County, Florida

. In addition to the analysis presented in MMS (2007b ) and BOEM (2012 a,b, c , 2013 ), recent and

o ngoing studies have explored the economic impacts of the Macondo spill including tourism and

" brand " damage (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 C oast is discussed in MMS ( 2007b ) and BOEM ( 2012a,b
, c , 2013 ). There are no routine IPFs that could affec t 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 shorebase s

. A large oil spill is the only relevant I PF. 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
The initial response for a large oil spill would be staged out of existing facilities wi th 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, d uring the Macondo spill, temporary staging areas were established in Louisiana, Mississippi, A labama, 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 needed. 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 . The proposed wellsites are located within Military Warning Area W

- 92

. Anadarko will comply with BOEM requirements and lease stipulations to avoid impacts on uses of the area by military vessels and aircraft s

. Fugro GeoServices, Inc. (20 03 ) reported that existing infrastructure is present near the proposed locations in cluding three existing wells, two 6

- i nch pipelines, an umbilical, and numerous cables noted during a nalysis of the 3D seismic data

. There are no IPFs from routine project activities that are likely to affect other marine uses of the lease area. A large oil spill is the only relevant accident

- related IPF. A small fuel spill would not have any impacts on other marine uses because spill response activities would be mainly within the lease area and the duration would be brief.

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### Impacts of a Large Oil Spill
An accidental spill would be unlikely to significantly affect shipping or other marine uses

. In the event of a large spill requiring numerous response vessels, coordination would be required to manage the vessel traffic for safe operations. Anadarko will comply with BOEM requirements and lease stipulations to avoid impacts on uses of the area by military vessels and aircraft.

In the event of a large spill requiring numerous vessels in the area, coordination would be required to ensure that no anchoring or seafloor

- disturb ing activities occur near the existing wells and pipelines

.



## D. Environmental Hazards

D. 1 Geologic Hazards

Fugro GeoServices, Inc. ( 2003 ) reported that the highly irregular seafloor in the southern mini

basin in western portion of Block 768 may represent a zone of potential modern seafloor instability associated with seafloor faulting and salt withdrawal. They have reported that although large

- scale slope failure is unlikely during temporary exploratory drilling, when planning production and development f acilities, the potential for seafloor instability should be considered

. The proposed wellsites were found to be free of significant geological hazards and were considered suitable for the proposed activities ( Fugro GeoServices, Inc.
, 2003 )

. See EP Sectio n 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

con sidered in the design criteria for the drilling rig s 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 eve nt of a hurricane, procedures as outlined in the Hurricane Evacuation Plan would be adhered to.



## D. 3 Currents and Waves

Metocean conditions such as sea states, wind speed, and ocean currents will be continuously monitored. Under most circumstances, physica l oceanographic conditions are not expected to have any effect on the proposed acti vities. 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 di srupt 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.

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## E. Alternatives

N o formal alternatives we re evaluated in this EIA for the EP . However, various technical and operational options
, including the location of the wellsite s and the selection of a drilling unit, were considered by Anadarko in developing the pr oposed 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 F ederal, S tate, and local requirements conce rning air pollutant emissions, discharges to water, and solid waste disposal. All project activities will be conducted under guidance by Anadarko ’s OSRP and will include the measures described in EP Section H

.



## G. Consultation

No persons or agencies were consulted during the preparation of this EIA.



## H. Preparers

Th is EIA was prepared by CSA Ocean Sciences Inc. Contributors included :

• M. John Thompson (Senior Scientist);

• John M. Tiggelaar II (Project Scientist);

• Heidi Etter (Project Scientist) ;

• Neal Phillips (Senior Scientist);

• Keith VanGraafeiland (Geospatial Manager);

• Kevin Noack (Geospatial Coordinator);

• Kristen L. Metzger (Library and Information Services Director); and

• Natalie Kraft (Technical Editor).



## I. References

Ackleh, A., G.E. Loup, J.W. Loup, B. Ma, J.J. Newcomb, N. Pal, N.A. Sidorovskaia, and C. Tiemann. 2012. Assessing the Deepwater Horizon oil spill impact on marine mammal population through acoustics: Endangered sperm whales. J. Acoust. Soc. Am. 131(3) : 2
, 306

- 2
, 314. Aten, L.E. 19 83. Indians of the upper Texas coast. New York, NY: Academic Press. 370 pp. Barkuloo, J.M. 1988. Report on the conservation status of the Gulf of Mexico sturgeon, Acipenser oxyrinchus desotoi. U.S. Department of the Interior, U.S. Fish and Wildlife Service, Panama City, FL. 33 pp.

Green Canyon Blocks 724 and 768 July 2014 Environmental Impact Analysis for Initial Exploration Plan Page 69 CSA

- Anadarko

- FL

- 14

- 2716

- 0 1

- R EP

- 01

- FINBarkaszi, M.J., M. Butler, R. Compton, A. Unietis, and B. Bennet. 2012. Seismic survey mitigation measures and marine mammal observer reports. U.S. Dept. of the Interior, Bureau of Ocean Energy Management , Gulf of Mexic o OCS Region, New Orleans, LA. OCS Study BOEM 2012

- 015. 53 pp. Bélanger, L. and J. Bédard. 1989. Responses of s taging Greater Snow Geese to h uman d isturbance. J

. Wildl

. Manage

. 53:713

- 719. Biggs, D.C. and P.H. Ressler. 2000. Water column biology, p p. 141

- 187. In: Continental Shelf Associates, Inc. Deepwater Program: Gulf of Mexico Deepwater Information Resources Data Search and Literature Synthesis. Volume I: Narrative Report. U.S. Department of the Interior, Minerals Management Service, Gulf of Mexico OCS Region, New Orleans, LA. OCS Study MMS 2000

- 049. Boehm, P., D. Turton, A. Raval, D. Caudle, D. French, N. Rabalais, R. Spies, and J. Johnson. 2001. Deepwater program: Literature review, environmental risks of chemical products used in Gulf of Mexico deepwater oil and gas operations. Volume I: Technical report. U.S. Department of the Interior, Minerals Management Service, Gulf of Mexico OCS Region, New Orleans, LA. OCS Study MMS 2001

- 011. 326 pp. Brooke, S. and W.W. Schroeder. 2007. State of deep coral ecosystems in the Gulf of Mexico region: Texas to the Florida Straits, pp. 271

- 306. In: S.E. Lumsden, T.F. Hourigan, A.W. Bruckner, and G. Dorr (eds.)

, The State of Deep Coral Ecosystems of the Un ited States. NOAA Tech. Memo. CRCP

- 3. Silver Spring, MD. 365 pp. Brooks, J.M., C. Fisher, H. Roberts, E. Cordes, I. Baums, B. Bernard, R. Church, P. Etnoyer, C. German, E. Goehring,
I. McDonald, Harry Roberts, T. Shank, D. Warren, S. Welsh, and G. Wolf f. 2012. Exploration and research of northern Gulf of Mexico deepwater natural and artificial hard

- bottom habitats with emphasis on coral communities: Reefs, rigs, and wrecks

— “ Lophelia II” Interim report. U.S. Dept. of the Interior, Bureau of Ocean En ergy Management, Gulf of Mexico OCS Region, New Orleans, LA. OCS Study BOEM 2012

- 106. 135 pp. Bureau of Ocean Energy Management (BOEM) . 2012a. Outer Continental Shelf Oil and Gas Leasing Program: 2012

- 2017. Final Programmatic Environmental Impact Statement. U.S. Department of the Interior, Bureau of Ocean Energy Management. OCS EIS/EA BOEM 2012

- 030. Bureau of Ocean Energy Management (BOEM)

. 2012b

. Gulf of Mexico OCS Oil and Gas Lease Sales: 2012

- 2017. Western Planning Area Lease Sales 229, 233, 238, 246
, and 248. Central Planning Area Lease Sales 227, 231, 235, 241
, and 247. Final Environmental Impact Statement. U.S. Department of the Interior , Bureau of Ocean Energy Management, Gulf of Mexico OCS Region. OCS EIS/EA BOEM 2012

- 019. 3 vol.
Bureau of Ocean Energy Management (BOEM)

. 2012 c

. Gulf of Mexico OCS Oil and Gas Lease Sale: 2012. Central Planning Area Lease Sale 216/222. Final Supplem ental Environmental Impact Statement. U.S. Department of the Interior, Bureau of Ocean Energy Management, Gulf of Mexico OCS R egion, New Orleans, LA. OCS EIS/EA
BOEM 2012

- 058. 2 vol. Bureau of Ocean Energy Management (BOEM)

. 2012 d

. Archaeology Survey Blocks. Website accessed on 11 April 2014

. http://www.boem.gov/Environmental

- Stewardship/Archaeology/surveyblocks

- pdf.aspx

. Bureau of Ocean Energy Man agement (BOEM)

. 2013. Gulf of Mexico OCS Oil and Gas Lease Sales: 2013

- 2014. Western Planning Are Lease Sale 233. Central Planning Area 231. Final Supplemental Environmental Impact Statement. U.S. Department of the Interior, Bureau of Ocean Energy Ma nagement, Gulf of Mexico OCS Region. OCS EIS/EA BOEM 2013

- 0118. Bureau of Ocean Energy Management, Regulation and Enforcement (BOEMRE) . 2010. Federal & Academic Scientists Return from Deep

- sea Research Cruise in Gulf of Mexico: Scientists Observe Damage to Deep

- sea Corals. Online news dated 4 November 2010. Website accessed 17 January 2014

. http://www.noaanews.noaa.gov/stories2010/20101104_coralcruise.html Camilli, R., C.M. Reddy, D.R. Yoerger, B.A.S. Van Mooy, M.V. Jakuba, J.C. Kinsey, C.P. McIntyre, S.P. Sylva, a nd J.V. Maloney. 2010. Tracking hydrocarbon plume transport and biodegradation at Deepwater Horizon

. Science 330(6001):201

- 204. Carmichael, R.H., W.M. Graha m, A. Aven, G.Worthy, and S. Howden. 2012. Were multiple stressors a ‘perfect storm’ for northern Gulf of Mexico bottlenose dolphins ( Tursiops truncatus ) in 2011? Website accessed 26 March 2014 at: http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0041155

. Carr, A. 1996. Suwannee River sturgeon, pp. 73

- 83. In: M.H. Carr (ed.), A Naturalist in Florida. Yale University Press, New Haven, CT.
Green Canyon Blocks 724 and 768 July 2014 Environmental Impact Analysis for Initial Exploration Plan Page 70 CSA

- Anadarko

- FL

- 14

- 2716

- 0 1

- R EP

- 01

- FINCenters for Disease Control and Preventi on. 2010a. Deepwater Horizon R esponse: NIOSH Health H azard
E valuation. Website accessed 17 January 2014 , updated 24 August 2011 at: http://www.cdc.gov/niosh/topics/oilspillresponse/gulfspillhhe.html

. Centers for Disease Control and Prevention. 2010b. Health Hazard Evaluation of Deepwater Horizon Response Workers, HETA 2010

- 0115. I nterim Report #6A. 11 pp. Website accessed 25 March 2014 at: http://www.cdc.gov/niosh/hhe/pdfs/interim_report_6.pdf

. Clapp, R.B., R.C. Banks, D. Morgan

- Jacobs, and W.A. Hoffman. 1982 a. Marine birds of the southeastern United States and Gulf of Mexico. Part I. Gaviiformes through Pelicaniformes. U.S. Fish and Wildlife Service, Office of Biological Services, Washington, D

. C. FWS/OBS

- 82/01. 637 pp. Clapp, R.B., D. Morgan

- Jacobs, an d R.C. Banks. 1982b. Marine birds of the southeastern United States and Gulf of Mexico. Part II. Anseriformes. U.S. Fish and Wildlife Service, Office of Biological Services, Washington, D

. C. FWS/OBS

- 82/20. 492 pp. Clapp, R.B., D. Morgan

- Jacobs, and R.C. Banks. 1983. Marine birds of the southeastern United States and Gulf of Mexico. Part III. Charadriiformes. U.S. Fish and Wildlife Service, Office of Biological Services, Washington,
D

. C. FWS/OBS

- 83/30. 853 pp. Coastal Environments, Inc. 1977. Cultural Resources Evaluation of the Northern Gulf of Mexico Continental Shelf. Prepared for the U.S. Department of the Interior, National Park Service, Office of Archaeology and Historic Preservation, Interagency Archaeological Services, Baton Rouge, LA . 4 vol. Coastal Environments, Inc. 1982. Sedimentary Studies of Prehistoric Archaeologica l Sites. Prepared for the U.S. Department of the Interior, National Park Service, Division of State Plans and Grants, Baton Rouge, LA.
Continental Shelf Associates, Inc. 1997. Characterization and trends of recreational and commercial fishing from the Florida panhandle. U.S. Department of Interior, Minerals Managem ent Service, Gulf of Mexico OCS Region, New Orleans, LA. USGS/BRD/CR

- 1997

- 0001 and OCS St udy MMS 97

- 0020. 333 pp. Continental Shelf Associates, Inc. 2002. Deepwater P rogram: Bluewater fishing and OCS activity, interactions between the fishing and petroleum industries in deepwaters of the Gulf of Mexico. U.S. Department of the Interior, Min erals Management Service, Gulf of Mexico OCS Region, New Orleans, LA. OCS Stu dy MMS 2002

- 078. Continental Shelf Associates, Inc. 2004. Final Report: Gulf of Mexico C omprehensive S ynthetic B ased M uds M onitoring P rogram. Report prepared for SBM Research Group, Housto n, TX. October 2004. 3 vol

. Continental Shelf Associates, Inc. 2006. Effects of oil and gas exploration and development at selected continental slope sites in the Gulf of Mexico. Volume II: Technical report. U.S. Department of the Interi or, Minerals Management Service, Gulf of Mexico OCS Region, New Orleans, LA. OCS Study MMS 2006

- 045.
Cruz

- Kaegi, M.E. 1998. Latitudinal variations in biomass and metabolism of benth ic infaunal communities. Ph.D. dissertation, Texas A&M University, College Station, TX. CSA International, Inc. 2007. Characterization of northern Gulf of Mexico deepwater hard

- bottom communities with emphasis on Lophelia coral. U.S. Department of the Interior, Minerals Management Service, Gulf of Mexico OCS Region, Ne w Orleans, LA. OCS Study MMS 2007

- 044. 169 pp. + app. Davis, R.W. and G.S. Fargion. 1996. Distribution and abundance of cetaceans in the north

- central and western Gulf of Mexico: Final report. U.S. Dep artmen t of the Interior, Minerals Management Servi ce, Gulf of Mexico OCS Region, New Orleans, LA. Davis, R.W., J.G. Ortega

- Ortiz, C.A. Ribic, W.E. Evans, D.C. Biggs, P.H. Ressler, J.H. Wormuth, R.R. Leben, K.D. Mullin, and B. Würsig. 2000. Cetacean habitat in the northern Gulf of Mexico, pp. 217

- 2 53. In: R.W. Davis, W.E. Evans, and B. Würsig (eds.), Cetaceans, sea turtles, and seabirds in the northern Gulf of Mexico: Distribution, abundance and habitat associations. Volume II: Technical report. U.S. Geological Survey, Biological Resources Division, U SGS/BRD/CR

- 1999

- 0006 and U.S. Department of the Interior, Minerals Management Service, Gulf of Mexico OCS Region, New Orleans, LA. OCS Study MMS 2000

- 003. 346 pp. Ditty, J.G. 1986. Ichthyoplankton in ner I tic waters of the northern Gulf of Mexico off Lo uisiana: Composition, relative abundance, and seasonality. Fish. Bull. 84(4):935

- 946. Ditty, J.G., G.G. Zieske, and R.F. Shaw. 1988. Seasonality and depth distribution of larval fishes in the northern Gulf of Mexico above 26°00’N. Fish. Bull. 86:811

- 82 3.

Green Canyon Blocks 724 and 768 July 2014 Environmental Impact Analysis for Initial Exploration Plan Page 7 1 CSA

- Anadarko

- FL

- 14

- 2716

- 0 1

- R EP

- 01

- FINEfroymson, R.A., W.H. Rose, S. Nemeth, and G.W. Suter II. 2000. E cological risk assessment framework for low altitude overflights by fixed

- wing and rotary

- wing military aircraft. Report prepared by Oak Ridge National Laboratory, Oak Ridge, TN. ORNL/ TM

- 2000/289: ES

- 5048. Ehrlich, P.R., D.S. Dobkin, and D. Wheye. 1992. Birds in Jeopardy: The Imperiled and Extinct Birds of the United States and Canada, including Hawaii and Puerto Rico. Stanford University Press, Palo Alto, CA. 261 pp.
Florida Fish a nd Wildlife Conservation Commission. 201 4a

. Loggerhead nesting in Florida. Website accessed 5 May 2014 at: http://myfwc.com/research/wildlife/sea

- turtles/nesting/loggerhead/

. Florida Fish and Wildlife Conservation Commission. 201 4b

. Green turtle nesting in Florida. Website accessed 5 May 2014 at: http://myfwc.com/research/wildlife/sea

- turtles/nesting/green

- turtle/

. Florida Fish and Wildlife Conservation Commission. 201 4c

. Leatherback nesting in Florida. Website accessed 5 May 2014 at: http://myfwc.com/research/wildlife/sea

- turtles/nesting/leatherback/

. Florida Fish and Wildlife Conservation Commission. 201 4 d

. Florida's endangered and threatened species

. Website accessed 25 March 2014 at: http://myfwc.com/media/1515251/Threatened_Endangered_Species.pdf

. Flower Garden Banks National Marine Sanctuary. 201 4 . Cnidarian species. Website a ccessed 5 May 2014
, updat ed 10 February 2014 at : http://flowergarden.noaa.gov/about/cnidarianlist.html

. Fox, D.A., J.E. Hightower, and F.M. Paruka. 2000. Gulf sturgeon spawning migration and habitat in the Ch octawhatchee River system, Alabama

- Florida. Trans. Am. Fish. Soc. 129:811

- 826. Fritts, T.H. and R.P. Reynolds. 1981. Pilot study of the marine mammals, birds, and t urtles in OCS areas of the Gulf of Mexico. U.S. Department of the Interior, Fish and Wi ldlife Service, Biological Services Program. FWS/OBS

- 81/36. Fugro GeoServices, Inc. 2003. Shallow Hazard Assessment, Gulf of Mexico, Green Canyon Blocks G C 723, 724, 768, & Vicinity
, Wellsite GC 768 BB Site Clearance Letters. Fugro Report Nos. 2402

- 200 4 to 27.2012

- 2582

. Fugro GeoServices, Inc. 2013

. Archaeological Assessment, Block 852

- 854, 897, & 898, DeSoto Canyon Area, Gulf of Mexico. Report No. 2413

- 059. Gallaway, B. (ed.). 1988. Northern Gulf of Mexico C ontinental S lope S tudy, F inal report: Year 4. Volume II: Synthesis report. Final report submitted to the U.S. Department of the Interior, Minerals Management Service, New Orleans, LA. Contract No. 14

- 12

- 0001

- 30212. Gallaway, B.J., J.G. Cole, and R.G. Fechhelm. 2003. Selected Aspects of the Ecology of the Continental Slope Fauna of the Gulf of Mexico: A Synopsis of the Northern Gulf of Mexico Continental Slope Study, 1983

- 1988

. U.S. Department of the Interior, Minerals Management Service, Gulf of Mexico OC S Region, New Orleans , LA. OCS Study MMS 2003

- 072. Geraci, J.R. and D.J. St. Aubin. 1987. Effects of offshore oil and gas development on marine mammals and turtles, pp. 587

- 617. In: D.F. Boesch and N.N. Rabalais (eds.), Long Term Environmental Effects of Offshore Oil and G as Development. Elsevier Applied Science Publ. Ltd., London and New York. Geraci, J.R. and D.J. St. Aubin. 1990. Sea M ammals and O il: C onfronting the R isks. Academic Press, San Diego. Gulf of Mexico Fishery Management Council. 2005. Generic A mendment N umber 3 for a ddressing E ssential F ish
H abitat R equirements, H abitat A reas of P articular C oncern, and a dverse e ffects of f ishing in the f ollowing
F ishery M anagement P lans of the Gulf of Mexico: S hrimp fishery of the Gulf of Mexico, United States waters red drum fishery of the Gulf of Mexico, reef fish fishery of the Gulf of Mexico coastal migratory pelagic resources (mackerels) in the Gulf of Mexico and South Atlantic, stone crab fishery of the Gulf of Mexico, spiny lobster in the Gulf of Mexico and Sout h Atlantic, coral and coral reefs of the Gulf of Mexico. Gulf of Mexico Fishery Management Council, Tampa, FL. Hazen, T.C., E.A. Dubinsky, T.Z. DeSantis, G.L. Andersen, Y.M. Piceno, N. Singh, J.K. Jansson, A. Probst, S.E. Borglin, J.L. Fortney, W.T. Strin gfellow, M. Bill, M.S. Conrad, L.M. Tom, K.L. Chavarria, T.R. Alus i, R. Lamendella, D.C. Joyner, C. Spier, J. Baelum, M. Auer, M.L. Zemla, R. Chakraborty, E.L. S onnenthal, P. D’haeseleer,
H.N. Holman, S. Osman, Z. Lu, J.D. Van Nostrand, Y. Deng, J. Zhou, a nd O.U. Mason. 2010. Deep

- sea oil plume enriches indigenous oil

- degrading bacteria. Science 330(6001):204

- 208.

Green Canyon Blocks 724 and 768 July 2014 Environmental Impact Analysis for Initial Exploration Plan Page 72 CSA

- Anadarko

- FL

- 14

- 2716

- 0 1

- R EP

- 01

- FINHess, N.A. and C.A. Ribic. 2000. Seabird ecology, pp. 275

- 315. In: R.W. Davis, W.E. Evans, and B. Würsig (eds.), Cetaceans, sea turtles, an d seabirds in the northern Gulf of Mexico: Distribution, abundance and habitat associations. Volume II: Technical report. U.S. Geological Survey, Biological Resources Division, USGS/BRD/CR

- 1999

- 0006 and U.S. Department of the Interior, Minerals Managemen t Service, Gulf of Mexico OCS Region, New Orleans, LA. OCS Study MMS 2000

- 003. 346 pp. Higashi, G.R. 1994. Ten years of fish aggregating device (FAD) design and developm ent in Hawaii. Bull. Mar. Sci. 55(2

- 3):651

- 666. Holand, P. 1997. Offshore Blowouts: Causes and Control. Gul f Publishing Co., Houston, TX. Holland, K.R., R.W. Brill, and R.K.C. Chang. 1990. Horizontal and vertical movements of yellowfin and bigeye tuna associated with fish aggregating devices. Fish. Bull. 88:493

- 507. Hsing, P

. - Y

. , B. Fu, E.A. Larcom, S.P. Berlet, T.M. Shank, A.F. Govindarajan, A. J. Lukasiewicz, P.M. Dixon, and C.R. Fisher. 2013. Evidence of lasting impact of the Deepwater Horizon oil spill on a deep Gulf of Mexico coral community

. Elementa: Science of th e Anthropocene 1: 000012 . Website accessed 26 March 2014 at: http://www.elementascience.org/article/info%3Adoi%2F10.12952%2Fjournal.elementa.000012

. IEM . 2010. A Study of the Economic Impact of the Deepwater Horizon Oil S pill. Prepared for Greater
New Orleans, Inc. October 2010. Website accessed 25 March 2014

. http://gnoinc.org/wp

- content/uploads/Economic_Impact_Study_Part_I_

- _Full_Report.pdf

. http://gnoinc.org/wp

- content/uploads/Economic_Impact_Study_Part_II_

- _Moratoria_FINAL.pdf

. http://gnoinc.org/wp

- content/uploads/Economic_Impact_Study_Part_III_

- _Public_Perception_FINAL.pdf

. Inter

- Agency Economic Report. 2010. Estimating the effects of the deepwater drilling moratorium on the Gulf coast economy. Website accessed 25 March 2014

. http://www.esa.doc.gov/Reports/estimating

- economic

- effects

- deepwater

- drilling

- moratorium

- gulf

- coast

- economy

. Intergovernmental Panel on Climate Change. 2007. Climate Change 2007: Synthesis Report. Contribution of Working Groups I, II and III to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. Geneva, Switzerland. 104 pp. Intergovernmental Panel on Climate Change. 20 14

. Climate Change 20 14 : Impacts, Adaptation and Vulnerability

. Yokohama, Japan

. http://www.ipcc.ch/report/ar5/wg2/

. International Association of Oil & Gas Producers. 2010. Risk assessment data directory : Blowout frequenci es. O GP Report No. 434

- 2. Website accessed 25 March 2014

. http://www.ogp.org.uk/pubs/434

- 02.pdf

. Ji, Z

. - G., W.R. Johnson, C.F. Marshall, and E.M. Lear. 2004. Oil

- Spill Risk Analysis: Contingency Planning Statistics for Gulf of Mexico OCS Activities. U.S. Department of the Interior, Minerals Management Service, Gulf of Mexico OCS Region. OCS Report MMS 2004

- 026. Jochens, A., D. Biggs, K. Benoit

- Bird, D. Engelhaupt, J. Gordon , C. Hu, N. Jaquet, M. Johnson, R. Leben, B. Mate, P. Miller, J. Ortega

- Ortiz, A. Thode, P. Tyack, and B. Würsig. 2008. Sperm whale seismic study in the Gulf of Mexico: Synthesis report. U.S. Department of the Interior, Minerals Management Service, Gulf of Mexico OCS Region, New Orleans, LA. OCS Study MMS 2008

- 006. 341 pp. Johnsgard, P.A. 1990. Hawks, Eagles, and Falcons of North America; Biology and Natural History. Smithsonian Institute Press, Washington. 403 pp. Joint Analysis Group. 2010a. Jo int Analysis Group (JAG) r eview of p reliminary d ata to e xamine s ubsurface oil in the vicinity of MC252#1 May 19 to June 19, 2010. Website accessed 25 March 2014

. http://gomex.erma.noaa.gov/layerfiles/7229/files/JAG_Data_Report_2_Subsurface%20Oil_Final.pdf

. Joint Analysis Group. 2010b. Joint Analysis Group (JAG) r eview of R/V Brooks McCall d ata to e xamine s ubsurface

o il. Website accessed 25 Mar ch 2014

. http://www.noaa.gov/sciencemissions/PDFs/JAG_Report_1_BrooksMcCall_Final_June20.pdf

. Joint Analysis Group. 2010c. Joint Analysis Group (JAG) review of preliminary data to examine oxygen levels in the vicinity of MC252#1 May 8 to August 9, 2010. Website accessed 25 March 2014

. http://www.noaa.gov/sciencemissions/PDFs/JAG_Oxygen_Report%20%28FINAL%20090410%29.pdf

.

Green Canyon Blocks 724 and 768 July 2014 Environmental Impact Analysis for Initial Exploration Plan Page 73 CSA

- Anadarko

- FL

- 14

- 2716

- 0 1

- R EP

- 01

- FINKennicutt, M.C. II. 2000. Chemical Oceanography, pp. 123

- 139. In: Continental Shelf Associates, Inc. Deepwater Program: Gulf of Mexico deepwater information r esources data search and literature synthesis. Volume I: Narrative report. U.S. Department of the Interior, Minerals Management Service, Gulf of Mexico OCS Region, New Orleans, LA. OCS Study MMS 2000

- 049. Kujawinski, E.B., M.C. Kido Soule, D.L. Valentin e, A.K. Boysen, K. Longnecker, and M.C. Redmond. 2011. Fate of dispersants associated with the Deepwater Horizon oil spill. Environ. Sci. Technol. 45(4): 1298

- 1306 . Website accessed 28 March 2014. http://pubs.acs.org/doi/abs/10.1021/es103838p

. LGL Ecological Research Associates, Ltd. 2006. Assessment o f t he e ffects o f u nderwater n oise f rom t he p roposed Neptune L NG Project

- Supplementary Biological Effects Report to Ecology and Environmen t, Inc. LGL Report No. 4200

- 2a
, 8 August 2006. 11 pp. Lohoefener, R., W. Hoggard, K. Mullin, C. Roden, and C. Rogers. 1990. Association of sea turtles with petroleum platforms in the north

- central Gulf of Mexico. U.S. Department of the Interior, Minerals Management Service, Gulf of Mexico OCS Region, New Orleans, LA. OCS Study MMS 90

- 0025. 90 pp. Lutcavage, M.E., P.L. Lutz, G.D. Bossart, and D.M. Hudson. 1995. Physiologic and clinicopathologic effects of crude oil on loggerhead sea turtles. A rch. Environ. Contam. Toxicol. 28:417

- 422. Lutcavage, M.E., P. Plotkin, B. Witherington, and P.L. Lutz. 1997. Human impacts on sea turtle survival,
pp. 387

- 409. In: P.L. Lutz and J.A. Musick (eds.), The Biology of Sea Turtles. CRC Press, Boca Raton, F L. MacDonald, I.R. (ed.). 2002. Stability and Change in Gulf of Mexico Chemosynthetic Communities. Volume II: Technical Report. U.S. Department of the Interior, Minerals Management Service, Gulf of Mexico OCS Region, New Orleans, LA. OCS Study MMS 200 2

- 036. 456 pp. Marine Mammal Commission (MMC) . 201 1

. Assessing the long

- term effects of the BP Deepwater Horizon o il s pill

on m arine m ammals in the Gulf of Mexico: A statement of research needs

. Website accessed 25 March 2014

. http://www.mmc.gov/reports/workshop/pdf/longterm_effects_bp_oilspil.pdf

. Minerals Management Service (MMS) . 2000. Gulf of Mexico Deepwater Operations and Activities: Environmental Assessment . U.S. Department of the Interior, Minerals Management Service, Gulf of Mexico OCS Region,
New Orleans, LA. OCS EIS/EA MMS 2000

- 001. Minerals Management Service (MMS) . 2007a. Outer Continental Shelf Oil & Gas Leasing Program: 2007

- 2012 Final Environmen tal Impact Statement. U.S. Department of the Interior, Minerals Management Service, Herndon, VA. OCS EIS/EA MMS 2007

- 003. April 2007. Minerals Management Service (MMS) . 2007b. Gulf of Mexico OCS Oil and Gas Lease Sales: 2007

- 2012. Western Planning Ar ea Sales 204, 207, 210, 215, and 218; Central Planning Area Sales 205, 206, 208, 213, 216, and 222. Final Environmental Impact Statement. U.S. Dep artmen t of the Interior, Minerals Management Service, Gulf of Mexico OCS Region. OCS EIS/EA MMS 2007

- 018. April 2007. Minerals Management Service (MMS) . 2008. Gulf of Mexico OCS Oil and Gas Lease Sales: 2009

- 2012; Central Planning Area Sales 208, 213, 216, and 222; Western Planning Area Sales 210, 215, and 218. Final Supplemental Environmental Impact Statement. U.S. Department of the Interior, Minerals Management Service, Gulf of Mexico OCS Region, New Orleans, LA. OCS EIS/EA MMS 2008

- 041. September 2008. Minerals Management Service (MMS) . 2009a. NTL No. 2009

- G39: Biologically Sensitive Underwater Features and Areas. U.S. Department of the Interior, Minerals Management Service, Gulf of Mexico OCS Region,
New Orleans, LA. Minerals Management Service (MMS) . 2009b. NTL No. 2009

- G40: Deepw ater Benthic Communities. U.S. Department of the Interior, Minerals Management Service, Gulf of Mexi co OCS Region, New Orleans, LA. Mississippi Department of Wildlife, Fisheries and Parks. 20 05

. Appendix VIII: Mississippi’s species of greatest conservation need by ecoregion , pp. 375

- 380

. In: Mississippi's Comprehensive Wildlife Conservation Strategy 2005

- 2015, Version 1. Website accessed 11 April 2014 at: http://www.mdwfp.com/media/63792/cwcs.pdf

. Morrow, J.V., Jr., J.P. Kirk, K.J. Killgore, H. Rugillio, and C. Knight. 1998. Status and recovery of G ulf sturgeon in the Pearl River system, Louisiana

- Mississippi. N. Am. J. Fish Manage. 18:798

- 808. Mullin, K., W. Hoggard, C. Roden, R. Lohoefener, C. Rogers, and B. Taggart. 1991. Cetaceans on the upper continental slope in the north

- central Gulf of Mexico. OCS Study/MMS 910027. U.S. Department of the Interior, Minerals Management Service, Gulf of Mexico OCS Regional Office, New Orleans, LA. 108 pp.

Green Canyon Blocks 724 and 768 July 2014 Environmental Impact Analysis for Initial Exploration Plan Page 74 CSA

- Anadarko

- FL

- 14

- 2716

- 0 1

- R EP

- 01

- FINMulli n, K.D. 2007. Abundance of cetaceans in the oceanic Gulf of Mexico based on 2003

- 2004 ship surveys. Available from: National Marine Fisheries Service, Southeast Fisheries Science Center, Pascagoula, MS. 26 pp. National Marine Fisheries Service. 2007. Endangered Species Act, Section 7 Consultation

– Biological Opinion. Gulf of Mexico Oil and Gas Activities: Five

- Year Leasing Plan for Western and Central Planning Areas 2007

- 2012. 29 June 2007.
National Marine Fisheries Service. 2009. Final Amendment 1 to the Consolidated Atlantic Highly Migratory Species Fishery Management Plan Essential Fish Habitat. Highly Migratory Species Management Division, Office of Sustainable Fisheries, Silver Spring, MD. June 2009. Website accessed 25 March 2014 at: http://www.nmfs.noaa.gov/sfa/hms/EFH/Final/FEIS_Amendment_Total.pdf

. National Marine Fisheries Service (NMFS) . 2010 a. Final Recovery Plan for the Sperm Whale ( Physeter macrocephalus ). Office of Protected Resources, Silver Spring, MD. December 2010. Website accessed 25 March 2014 at: http://www.nmfs.noaa.gov/pr/pdfs/rec overy/final_sperm_whale_recovery_plan_21dec.pdf

. National Marine Fisheries Service. 2010 b . Gulf sturgeon ( Acipenser oxyrinchus desotoi ). Website accessed 17 January 2014 , updated 27 February 201 3

. http://www.nmfs.noaa.gov/pr/species/fish/gulfsturgeon.htm
National Marine Fisheries Service (NMFS) . 2010 c . Sea turtles, dolphins, and whales and the Gulf of Mexico oil spill. Website accessed 25 March 2014; updated 13 December 2013 at : http://www.nmfs.noaa.gov/pr/health/oilspill.htm

. National Marine Fisheries Service (NMFS) . 2010 d

. Deepwater Horizon/BP oil spill: size and percent coverage of fishing area closures due to BP oil spill. Website accessed 25 March 2014 at: http://sero.nmfs.noaa.gov/deepwa ter_horizon/size_percent_closure/index.html
National Marine Fisheries Service (NMFS) and U.S. Fish and Wildlife Service (USFWS) . 2008. Recovery Plan for the Northwest Atlantic Population of the Loggerhead Sea T urtle ( Caretta caretta ), Second R evision. W ebsite accessed 25 March 2014 at: http://www.nmfs.noaa.gov/pr/pdfs/recovery/turtle_loggerhead_atlantic.pdf

. National Marine Fisheries Service, U.S. Fish and Wildlife S ervice
, and Secretaría de Medio Ambiente y Recursos Naturales ( SEMARNAT ) . 201 1 . Bi

- National Recovery Plan for the Kemp‘s Ridley Sea Turtle ( Lepidochelys kempii ), Second Revision. http://www.nmfs.noaa.gov/pr/pdfs/recovery/kempsridley_revision2.pdf National Oceanic and Atmospheric Administration (NOAA) . 2006. Fact Sheet: Small Diesel Spills (500

- 5,000 gallons). NOAA Scientific Support Team, Hazardous Materials Response and Assessment Division, National Oceanic and Atmospheric Administration. Seattle, W A . 2 pp. National Oceanic and A tmospheric Administration (NOAA) . 2010

. Oil and Sea Turtles. Biol ogy, Planning and Response. Website accessed 25 March 2014 at: http://response.restoration.noaa.gov/sites/default/files/Oil_Sea_Turtles.pdf

. National Oceanic and Atmospheric Administration (NOAA) . 201 4 . 2010

- 2014 Cetacean Unusual Mortality Event in Northern Gulf of Mexico. Website accessed 30 June 2014, updated 2 4 June 2014 at: http://www.nmfs.noaa.gov/pr/health/mmume/cetacean_gulfofmexico.htm

. National Park Service . 2010. Breton Wilderness 300 km Radius. Website accessed 25 March 2014 at : http://w ww2.nature.nps.gov/air/Permits/ARIS/docs/bretMap300.pdf

. National Research Council. 1983. Drilling Discharges in the Marine Environment. National Academy Press, Washington, DC. 180 pp.
National Research Counci l . 2003 a . Oil in the Sea III: Inputs, Fat es, and Effects. National Academies Press, Washington, DC. 182 pp. + app.
National Research Council. 2003b. Ocean N oise and M arine M ammals. Ocean Studies Board, National Academies Press, Washington, DC. 204 pp. Neff, J.M. 1987. Biological effects o f drilling fluids, drill cuttings and produced waters, pp. 469

- 538. In: D.F. Boesch and N.N. Rabalais (eds.), Long

- Term Effects of Offshore Oil and Gas Development. Elsevier Applied Science Publishers, London.

Green Canyon Blocks 724 and 768 July 2014 Environmental Impact Analysis for Initial Exploration Plan Page 75 CSA

- Anadarko

- FL

- 14

- 2716

- 0 1

- R EP

- 01

- FINNeff, J.M., S. McKelvie, and R.C. Ayers, Jr. 2000. Environmental impacts of synthetic based drilling fluids. Prepared by Robert Ayers & Associates, Inc. U.S. Department of the Interior, Minerals Management Service, Gulf of Mexico OCS Region, New Orleans, LA. OCS Study MMS 2000

- 064. 118 pp. Nef f, J.M., A.D. Hart, J.P. Ray, J.M. Limia, and T.W. Purcell. 2005. An assessment of seabed impacts of synthetic

- based drilling

- mud cuttings in the Gulf of Mexico. 2005 SPE/EPA/DOE Exploration and Production Environmental Conference, 7

- 9 March 2005, Galve ston, Texas, USA. SPE 94086. Nelson, H.F. and E.E. Bray. 1970. Stratigraphy and History of the Holocene Sediments in the Sabine

- High Island Area, Gulf of Mexico. In: Morga n , J.P. (ed.) Deltaic Sedimentation; Modern and Ancient. Special Publn.
No. 15. Tulsa, OK: SEPM. Nowlin, W.D., Jr., A.E. Jochens, S.F. DiMarco, R.O. Reid, and M.K. Howard. 2001. Deepwater Physical Oceanography Reanalysis and Synthesis of Historical Data: Synthesis Report. U.S. Department of the Interior, Minerals Management Service , Gulf of Mexico OCS Region, New Orleans, LA. OCS Study MMS 2001

- 064. 528 pp. Operational Science Advisory Team. 2010. Summary report for sub

- surface and sub

- sea oil and dispersant detection: Sampling and monitoring. Prepared for Paul F. Zukunft, U.S. Coast Guard Fe deral On

- Scene Coordinator, Deepwater Horizon MC252. December 17, 2010. http://www.restorethegulf.gov/sites/default/files/documents /pdf/OSAT_Report_FINAL_17DEC.pdf

. Oxford Economics. 2010. Potential impact of the Gulf oil spill on tourism. Report prepared for the U.S. Travel Association. Website accessed 25 March 2014 at: http://www.ustravel.org/sites/default/files/page/2009/11/Gulf_Oil_Spill_Analysis_Oxford_Economics_710.pdf

. Peake, D.E. 1996. Bird surveys, pp. 271

- 304. In: R.W. Davis and G.S. Fargion (eds. ), Distribution and abundance of cetaceans in the north

- central and western Gulf of Mexico, Final report. Volume II: Technical report. Prepared by the Texas Institute of Oceanography and the National Marine Fisheries Service. U.S. Department of the Inte rior, Minerals Management Service, Gulf of Mexico OCS Region Office, New Orleans, LA. OCS Study MMS 96

- 0027. 357 pp. Pearson, C.E., D.B. Kelley, R.A. Weinstein, and S.W. Gagliano. 1986. Archaeological investigations on the Outer Continental Shelf: A st udy within the Sabine River valley, offshore Louisiana and Texas

. U.S. Department of the Interior, Minerals Management Service, Reston, VA. OCS Study MMS 86

- 0119. 314 pp. Powers, K. 1987. Seabirds, pp. 194

- 201. In: J.D. Milliman and W.R. Wright (eds. ), The Marine Environment of the U.S. Atlantic Continental Slope and Rise. Jones and Bartlett Publ., I nc. Boston/Woods Hole, MA. 275 pp. Pritchard, P.C.H. 1997. Evolution , phylogeny, and current status, pp. 1

- 28. In: Lutz, P.L. and J.A. Musick ( eds. ), The Biology of Sea Turtles. Boca Raton, FL: CRC Press. Rathbun, G.B. 1988. Fixed

- wing airplane versus helicopter surveys of manatees. Mar. Mamm. Sci. 4(1):71

- 75. Relini, M., L.R. Orsi, and G. Relini. 1994. An offshore buoy as a FAD in the Mediterra nean. Bull. Mar. Sci. 55(2

- 3):1,099

- 1,105. Richards, W.J., T. Leming, M.F. McGowan, J.T. Lamkin, and S. Kelley

- Farga. 1989. Distribution of fish larvae in relation to hydrographic features of the Loop Current boundary in the Gulf of Mexico. Rapp. P.

- v. Reu n. Cons. Int. Explor. Mer. 191:169

- 176. Richards, W.J., M.F. McGowan, T. Leming, J.T. Lamkin, and S. Kelley. 1993. Larval fish assemblages at the Loop Current boundary in the Gulf of Mexico. Bull. Mar. Sci. 53(2):475

- 537. Richardson, W.J., C.R. Gre ene, Jr., C.I. Malme, and D.H. Thomson. 1995. Marine Mammals and Noise. Academic Press, San Diego. 576 pp. Rodgers, J., Jr, and S. Schwikert. 2002. Buffer Zone Distances to Protect Foraging and Loafing Waterbirds from Disturbances by Personal Watercr aft and Outboard

- Powered Boats. Conserv. Biol. 16:216

- 224. Ross, S.W., A.W.J. Demopoulos, C.A. Kellogg, C.L. Morrison, M.S. Nizinski, C.L. Ames, T.L. Casazza, D. Gualtieri,
K. Kovacs, J.P. McClain, A.M. Quattrini, A.Y. Roa

- Varón, and A.D. Thaler. 2012. Deepwater Program: Studies of Gulf of Mexico lower continental slope communities related to chemosynthetic and hard substrate habitats: U.S. Geological Survey Open

- File Report 2012

- 1032. 301 pp.

Green Canyon Blocks 724 and 768 July 2014 Environmental Impact Analysis for Initial Exploration Plan Page 76 CSA

- Anadarko

- FL

- 14

- 2716

- 0 1

- R EP

- 01

- FINRowe, G.T. and M.C. Kennicutt II. 2009. Northern Gulf of M exico Continental Slope Habitats and Benthic Ecology Study. Final Report. U.S. Department of the Interior, Minerals Managem ent Service, Gulf of Mexico OCS Region, New Orleans, LA. OCS Study MMS 2009

- 039. 456 pp. Russell, R.W. 2005. Interactions betwe en migrating birds and offshore oil and gas platforms in the northern Gulf of Mexico: Final Report. U.S. Dep artmen t of the Interior, Minerals Managem ent Service, Gulf of Mexico OCS Region, New Orleans, LA. OCS Study MMS 2005

- 009. 348 pp. Salmon, M. and J. Wyneken. 1990. Do swimming loggerhead sea turtles ( Caretta caretta ) use light cues for offshore orientation? Mar. Freshw. Behav. Phy. 17(4): 233

- 246. Schwacke, L.H., C.R. Smith, F. I. Townsend, R.S. Wells, L.B. Hart, B.C. Balmer, T.K. Collier, S. De Guise, M.M. Fry, L.J. Guillette, Jr., S.V. Lamb, S.M. Lane, W.E. McFee, N.J. Place, M.C. Tumlin, G.M. Ylitalo, E.S. Zolman, and
T.K. Rowles. 2014. Health of Common Bottlenose Dolphins ( Tursiops truncatus ) in Barataria Bay, Louisiana, f ollowing the Deepwater Horizon Oil Spill. Environ. Sci. Technol. 48 (1): 93

- 103. Website accessed 26 March 2014 at: http://pubs.acs.org/doi/abs/10.1021/es403610f

. Sea Turtle Restoration Project. 2013 . Ke mp’s ridley protection campaign. Website accessed 11 April 2014 at: http://blog.seaturtles.org/section.php?id=41

. Share the Beach. 2014

. Nesting season statistics. Website accessed 11 April 2 014

. http://www.alabamaseaturtles.com/nesting

- season

- statistics/ Smultea, M.A., J.R. Mobley, Jr., D. Fertl, and G.L. Fulling. 2008. An unusual reaction and other observations of sperm whales near fixed wing aircraft. Gulf. Carrib. Res. 20:75

- 80. Solomon, G.M. and S. Janssen. 2010. Health Effects of the Gulf Oil Spill. JAMA 304(10):1,118

- 1,119. Spier, C., W.T. Stringfellow, T.C. Hazen, and M

. Conrad. 2013. Distribution of hydrocarbons released during the 2010 MC252 oil spill in deep offshore waters. Environmental Pollution 173: 224

- 230. State of Louisiana Department of Wildlife and Fisheries. 2013. Species by parish list. Website acces sed
11 April 2014 at: http://www.wlf.louisiana.gov/wildlife/species

- parish

list?order=field_com_name_value&sort=asc&tid=All&type_1=All

. Sulak, K.J. and J.P. Clugston. 1998. Early life history stages of G ulf sturgeon in the S uwannee River, Florida. Trans. Am. Fish. Soc. 127:758

- 771. Todd, V. L. G., W.D. Pearse, N.C. Tregenza, P.A. Lepper, and I.B. Todd. 2009. Diel echolocation activity of harbour porpoise s ( Phocoena phocoena ) around North Sea offshore gas installations. ICES J. Mar. Sci. , 66: 734

– 745. Tuxbury, S.M. and M. Salmon. 2005. Competitive interactions between artificial lighting and natural cues during seafinding by hatchling marine turtles. B iol. Conserv. 121: 311

- 316. U.S. Environmental Protection Agency. 2013. The green book nonattainment areas for criteria pollutants. Website accessed 11 April 2014; updated 5 December 2013 at: http://www.epa.gov/air/oaqps/greenbk

. U.S. Fish and Wildlife Service (USFWS) . 2001. Florida manatee recovery plan ( Trichechus manatus latirostris ), Third Revision. U.S. Fish and Wildlife Service, Southeast Region, Atlanta, GA.
U.S. Fish and Wildlife Ser vice (USFWS) . 2003. Recovery plan for the Great Lakes Piping Plover ( Charadrius melodus ). Fort Snelling, Minnesota. September 2003. U.S. Fish and Wildlife Service (USFWS) . 2007. International Recovery Plan: Whooping Crane ( Grus americana ), Third Revi sion. Albuquerque, New Mexico. March 2007.
U.S. Fish and Wildlife Service (USFWS) . 2010a. All about piping plovers. Website accessed 25 March 2014 at: http://www.fws.gov/plover/facts.html

. U.S. Fish and Wildlife Service (USFWS) . 2010 b

. Beach

- n esting Birds of the Gulf

. Website accessed 25 March 2014
at: http://www.fws.gov/home/dhoilspill/pdfs/DHBirdsOfTheGulf.pdf

. U.S. Fish and Wildlife Service (USFWS) . 2010 c

. Find endangered species

. Website accessed 25 March 2014 at: http://www.fws.gov/endangered/

. U.S. Fish and Wildlife Service (USFWS) . 2010 d . Effects of oil on wildl ife and habitat. Website accessed 25 March 2014 at: http://www.fws.gov/home/dhoilspill/pdfs/DHJICFWSOilImpactsWildlifeFactSheet.pdf

.

Green Canyon Blocks 724 and 768 July 2014 Environmental Impact Analysis for Initial Exploration Plan Page 77 CSA

- Anadarko

- FL

- 14

- 2716

- 0 1

- R EP

- 01

- FINU.S. Fish and Wildlife Ser vice (USFWS) . 2011. FWS Deepwater Horizon Oil Spill Response. Bird Impact Data and Consolidated Wildlife Reports. Deepwater Horizon Bird Impact Data from the DOI

- ERDC NRDA Database 12 May 2011. Website accessed 25 March 2014 at: http://www.fws.gov/home/dhoilspill/pdfs/Bird%20Data%20Species%20Spreadsheet%2005122011.pdf

. U.S. Fish and Wildlife Servic e . 201 3 . Hawksbill sea turtle ( Eretmochelys imbricata ). Website accessed 25 March 2014 at: http://www.fws.gov/northflorida/SeaTurtles/Turtle%20Factsheets/hawksbill

- sea

- turtle.htm

. U.S. Fish and W ildlife Service
, Gulf States Marine Fisheries Commission , and National Marine Fisheries Service

. 1995. Gulf Sturgeon Recovery /Management Plan. 170 pp. Website accessed 25 March 2014 at: http://www.nmfs.noaa.gov/pr/pdfs/recovery/sturgeon_gulf.pdf

. Wakeford, A. 2001. State of Florida conservation plan for Gulf sturgeon ( Acipencer oxyrinchus desotoi ). Florida Marine Research Institute Technical Report TR

- 8. St. Petersburg, FL. Waring
, G.T., E. Josephson, K. Maze

- Foley, and P.E. Rosel ( eds .)

. 2013. U.S. Atlantic and Gulf of Mexico Marine Mammal Stock Assessments

– 2012. NOAA Tech

. Memo

. NMFS NE 223. 419 p p

. Wei, C.

- L. 2006. The bathymetric zonation and community structure of deep

- sea macrobenthos in the northern Gulf of Mexico. M.S. thesis, Texas A&M University. Website accessed 11 April 2014 at: http://repository.tamu.edu/handle/1969.1/4927

. White, H.K., P. Hsing, W. Cho, T.M. Shank, E.E. Cordes, A.M. Quattrini, R.K. Nelson, R. Camilli, A.W.J. Demopoulous, C.R. German, J.M. Brooks, H.H. Roberts, W. Shedd, C.M. Reddy, and C.R. Fisher. 2012. Im pact of the Deepwater Horizon oil spill on a deep

- water coral community in the Gulf of Mexico

. Proc. Nat. Acad. Sci. 109(50):20,303

- 20,308. Website accessed 25 March 2014 at: http://www.pnas.org/content/early/2012/03/23/1118029109.full.pdf+html?sid=56e8cdfe

- 2830

- 43f8

- 9d08

- 8eca0efd27e2

. Whooping Crane Eastern Partnership

. 201 3

. Whopping Crane Numbers 2002 thru 2013. Website acc essed 25 March 2014 at: http://www.bringbackthecranes.org/technicaldatabase/recovery/wc_nos_02to11.html

. Wiese, F.K., W.A. Montevecchi, G.K. Davoren, F. Huettmann, A.W. Diamond, and J. Linke. 2001. Seabirds at risk around offshore oil platforms in the north

- west Atlantic. Mar. Poll. Bull. 42(12):1,285

- 1,290. Wilson, J. 2003. Manatees in Louisiana. Louisiana Conservationist

. July/August 2003. 7 pp . Website accessed 25 March 2014 at: http://www.lamer.lsu.edu/pdfs/Manatees_LaConservArticle.pdf

. Witherington, B.E. 1997. The problem of photopollution for sea turtles and other nocturnal animals, pp. 303

- 328. In: J.R. Clemmons and R. Buchholz (eds.), Behavioral Approaches to Conservation in the Wild. Cambridge University Press, Cambridge, England. Würsig, B., S.K. Lynn, T.A. Jefferson, and K.D. Mullin. 1998. Behaviour of cet aceans in the northern Gulf of Mexico relative to survey ships and aircraft. Aquat. Mamm. 24: 41

- 50. Würsig, B., T.A. Jefferson, and D.J. Schmidly. 2000. The Marine Mammals of the Gulf of Mexico. Texas A&M University Press, College Station, TX. 232 p p.

Green Canyon Blocks 724 and 768 July 2014 Environmental Impact Analysis for Initial Exploration Plan Page 78 CSA

- Anadarko

- FL

- 14

- 2716

- 0 1

- R EP

- 01

- FIN

### O ADMINISTRATIVE INFORMATION

(a) Proprietary Information

Proprietary copies of this plan contain inform ation not available to the public and include structure maps, seismic information, cross sections, depths of wells, etc.

(b) Bibliography

Shallow Hazards Report Final Sale Package for Central Gulf of Mexico Sale Number 222.