UNITED STATES GOVERNMENT MEMORANDUM

To: Public Information (MS 5030)

Plans Section, Office of Field 

Operations (MS 5231)

Public Information copy of Exploration Plan

Control # - S-07534

Type - Supplemental Exploration Plan

Lease(s) - OCS-G32673 Block - 325 Walker Ridge Area

Operator - Woodside Energy (USA) Inc.

Subsea Wells A, B, C, and D

DP SEMISUBMERSIBLE

Attached is a copy of the subject plan for public comments on issues that 

should be addressed in an Environmental Assessment.

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

Michelle Griffitt

Plan Coordinator

Description -

Rig Type -

Subject:

From:

October 12, 2012



 

 

TABLE OF CONTENTS

Plan Contents (§§ 250.211 and 250.241) 

(a) Plan Information Form. 

(b) Location Map. 

(c) Safety and pollution prevention features. 

(d) Storage tanks and production vessels. 

(e) Pollution prevention measures 

(f) Additional measures. 

General Information (§§ 250.213 and 250.243) 

(a) Applications and permits. 

(b) Drilling fluids. 

(c) Production. 

(d) Oils characteristics. 

(e) New or unusual technology. 

(f) Bonding statement. 

(g) Oil spill financial responsibility (OSFR). 

(h) Deepwater well control statement.

(i) Suspensions of production. 

(j) Blowout scenario. [3 (b), (c) and (i) proprietary]

(k) Chemical products. 

Geological Information (§§ 250.214 and 250.244) 

(a) Geological description. 

(b) Structure contour maps. 

(c) Interpreted two-dimensional (2-D) and/or three-dimensional (3-D) seismic lines. 

(d) Geological structure cross-sections. Provide interpreted geological structure may be 

(e) Shallow hazards report. 

(f) Shallow hazards assessment. 

(g) High-resolution seismic lines. 

(h) Stratigraphic column. 

(i) Time vs. depth tables. 

(j) Geochemical information. 

(k) Future G&G activities. 

Hydrogen Sulfide (H2S) Information (§§ 250.215 and 250.245) 

a) Concentration. 

(b) Classification. 

(c) H2S Contingency Plan. 

Mineral Resource Conservation Information (§ 250.246) 

(a) Technology and reservoir engineering practices and procedures. 

(b) Technology and recovery practices and procedures. 

(c) Reservoir development. 

PUBLIC INFORMATION
 

 

Biological, Physical, and Socioeconomic Information (§§ 250.216 and 250.247) 

(a) Chemosynthetic communities report. 

(b) Topographic features map. 

(c) Topographic features statement (shunting). Not applicable. 

(d) Live bottoms (Pinnacle Trend) map. 

(e) Live bottoms (low relief) map. 

(f) Potentially sensitive biological features. 

(g) Remotely operated vehicle (ROV) monitoring survey plan. 

(h) Threatened and endangered species information. 

(i) Archaeological report. 

(j) Air and water quality information. 

(k) Socioeconomic information. 

Waste and Discharge Information (§§ 250.217 and 250.248) 

(a) Projected generated wastes. 

(b) Projected ocean discharges. 

(c) Modeling report. 

(d) NPDES permits. 

(e) Cooling water intakes. 

Air Emissions Information (§§ 250.218 and 250.249) 

(a) Emissions worksheets and screening questions 

Oil Spills Information (§§ 250.219 and 250.250) 

(a) Oil spill response planning. 

(i) Regional or subregional OSRP information. 

(ii) Spill response sites. 

(iii)OSRO information. 

(iv) Worst-case scenario determination. 

(b) Oil spill response discussion. 

(c) Modeling report. 

Environmental Monitoring Information (§§ 250.221 and 250.252) 

(a) Monitoring systems. 

(b) Flower Garden Banks National Marine Sanctuary. 

Lease Stipulations Information (§§ 250.222 and 250.253) 

Environmental Mitigation Measures Information (§§ 250.223 and 250.254) 

Decommissioning Information (§ 250.255) 

Related Facilities and Operations Information (§ 250.256) 

(a) Related OCS facilities and operations. 

(b) Transportation system. 

(c) Produced liquid hydrocarbons transportation vessels. 
 

 

Support Vessels and Aircraft Information (§§ 250.224 and 250.257) 

(a) General. 

(b) Diesel oil supply vessels. 

(c) Drilling fluids transportation

(d) Solid and liquid wastes transportation. 

(e) Vicinity map. 

Onshore Support Facilities Information (§§ 250.225 and 250.258) 

(a) General. 

(b) Support base construction or expansion. 

(c) Support base construction or expansion timetable. 

(d) Waste disposal. 

(e) Air emissions. 

(f) Unusual solid and liquid wastes. 

Sulphur Operations Information (§ 250.259) 

Coastal Zone Management Act (CZMA) Information (§§ 250.226 and 250.260) 

(a) Consistency certification. 

(b) Other information

Environmental Impact Analysis (EIA) (§§ 250.227 and 250.261) 

(a) IPF’s from the proposed activities. 

(b) Affected environment. 

(c) Impact analysis. 

(d) Environmental hazards. 

(e) Alternatives. 

(f) Mitigation measures. 

(g) Consultation. 

(h) Preparers. 

(i) References. 

Administrative Information (§§ 250.228 and 250.262) 

(a) Exempted information description (public information copies only). 

(b) Bibliography. 

Appendix A 

Plan Information Form 

Appendix B 

Location Plat 

Bathemetry Map

 

Appendix C

Blowout Scenario 

WCD Assumptions and Calculations
 

 

Appendix D

Interpreted 2-D or 3-D Seismic Lines 

Geological Structure Cross-Sections 

High Resolution Seismic Lines 

Stratigraphic Column 

Time VS. Depth Tables 

Geochemical Information

Appendix E

Vicinity Map

Shallow Hazard and Archaeological Assessments

High Resolution Seismic Lines

Appendix F 

Air Quality Review

Appendix G

Oil Spill Response Discussion

Oil Spill Response Certification

Appendix H 

Consistency Certification

Appendix I

Environmental Impact Analysis
 

 

Revised Exploration Plan

Woodside Energy (USA), Inc. 

Walker Ridge Block 325

Locations “A-D” 

Lease OCS-G 32673

Plan Contents (§§ 250.211 and 250.241)

Woodside Energy (USA) Inc. (Woodside), as designated Operator of the subject lease, hereby 

submits t his pr oposed Supplemental E xploration P lan in acco rdance w ith t he r egulations 

contained in Title 30 C FR 250.200-204 and more specifically defined in the Bureau of Safety 

and E nvironmental E nforcement (BSEE) [ formerly Bureau o f O cean Energy M anagement, 

Regulation and Enforcement (BOEMRE)] NTL’s 2008-G04, 2009-G27 and 2009-N06. Under 

this Exploration Plan (EP), Woodside plans to drill and temporarily abandon four (4) wells. The 

Initial Exploration Plan for Locations A-C, Control No. N-9414, was approved September 23, 

2009. A supplemental Location D was submitted on November 17, 2011 and was given Control 

No. S -7534. Woodside pr oposes t o r evise C ontrol N o. S-7534 by adding Locations A -C to 

comply w ith N TL 201 0-N06, r evising Location D an d revising t he Worst C ase D ischarge 

Scenarios as well as commencement dates. 

Woodside’s Plan, as detailed in this EP, is to use a single dynamic positioning semi submersible 

(DPSS) M obile O ffshore D rilling U nit ( MODU), th e Maersk D eveloper or e quivalent r ig ( the 

“Rig”), to d rill one exploration w ell i n t he Walker R idge Block 3 25 (WR 325) , l ocated 

approximately 165 miles from the nearest shoreline (Louisiana), 185 miles from the supply base 

at Fourchon, LA and 195 miles from the helicopter terminal at Amelia, LA. The initial drilling 

activities ar e tentatively planned t o c ommence on or a bout January 1, 201 3 and l ast 

approximately 150 days. T he timeframe to complete the initial drilling activities is an estimate 

based on the best available information regarding downhole conditions likely to be encountered 

while drilling the well and not intended to be a limitation. 

The rig to be utilized will be a DPSS and will be equipped with state-of-the-art drilling and well 

control equipment. It is a largely self-contained drilling vessel with accommodations for a crew 

up t o 138 persons on b oard i ncluding qua rters, g alley a nd s anitation f acilities. T he R ig w ill 

comply w ith t he requirements i n N TL 2010 -N05 a nd t he Interim F inal R ules. T he dr illing 

activities w ill be s upported b y t he s upport ve ssels a nd a ircraft as w ell as ex isting o nshore 

facilities. Woodside has e mployed or c ontracted w ith t rained pe rsonnel t o c arry out i ts 

exploration activities. Woodside employees and contractors are experienced at operating in the 

Gulf o f M exico an d are w ell v ersed i n all F ederal a nd S tate l aws regulating ope rations. 

Woodside’s em ployees an d co ntractors s hare Woodside’s d eep c ommitment to o perating in a 

safe and environmentally responsible manner. 

Woodside, t hrough i ts pa rent and a ffiliate c orporations, ha s e xtensive e xperience s afely 

exploring for oil and gas. Woodside will draw upon this experience in organizing and carrying 

out i ts pl anned dr illing program. Woodside believes t he b est w ay to m anage bl owouts i s t o 

prevent them from occurring. Significant effort goes into the design and execution of wells and 

into bui lding a nd m aintaining s taff c ompetence. In t he unl ike e vent of a s pill, Woodside 

Regional Oil S pill R esponse P lan i s de signed t o c ontain a nd r espond t o a s pill t hat m eets o r 
 

 

exceeds t he w orst cas e discharge ( WCD) s cenario d etailed i n Appendix C of t his P lan. T he 

WCD d oes n ot ta ke in to a ccount p otential f low mitig ating f actors s uch a s w ell b ridging, 

obstructions in wellbore, reservoir barriers or early intervention. Woodside continues to invest 

in i mprovements to th e s afety and r eliability o f o ur w ell s ystems. A ll o perations w ill b e 

conducted i n ac cordance w ith ap plicable F ederal an d S tate l aws, r egulations, an d l ease an d 

permit requirements. Woodside will have trained personnel and monitoring programs in place to 

ensure such compliance. 

(a) Plan Information Form 

 

An OCS Information Form with details of the proposed drilling operations as provided for in this 

Plan along with a tentative activity schedule is included as Appendix A. 

(b) Bathymetry Map, Location Plat , Anchor Pattern, and Anchor Site Clearance

A Well Location Plat and a Bathymetry Map are included as Appendix B. There are no anchors 

associated with this plan.

(c) Safety and Pollution Prevention Features

Safety features on the MODU will include well control, pollution prevention, welding procedure, 

and blowout prevention equipment as described in Title 30 C FR Part 250, Subparts C, D, E, G 

and O ; an d as f urther cl arified b y Bureau of S afety and E nvironmental E nforcement ( BSEE)

Notice t o Lessees, a nd c urrent pol icy m aking i nvoked b y t he Bureau o f S afety and 

Environmental E nforcement ( BSEE), E nvironmental P rotection A gency a nd t he U .S. C oast 

Guard. T he appropriate life boats, life rafts, life jackets, ring buoys, etc., as prescribed by the 

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

In a ccordance w ith T itle 30 C FR P art 250, S ubpart O, a n ope rator i s t o e nsure W ell C ontrol 

Training is provided for lessee and contractor personnel engaged in well control operations in the 

OCS G ulf of M exico. F urther, t he ope rator i s charged w ith t he r esponsibility t o not c reate 

conditions t hat w ill pos e unr easonable r isk t o t he publ ic he alth, l ife, p roperty, aquatic l ife, 

wildlife, recreation, navigation, commercial fishing, or other uses of the ocean.

Supervisory and c ertain designated pe rsonnel on -board th e f acility are to b e f amiliar w ith th e 

effluent limitations and guidelines for overboard discharges into the receiving waters, as outlined 

in the latest NPDES General Permit GMG290000. Some of these pollution prevention measures 

include installation of curbs, gutters, drip pans, and drains on dr illing deck areas to collect all 

contaminants and debris. 

Bureau of S afety and Environmental E nforcement ( BSEE) is required t o c onduct ons ite 

inspections o f o ffshore facilities to c onfirm o perators a re complying with le ase s tipulations, 

operating r egulations, a pproved pl ans, and ot her c onditions; a s w ell as t o a ssure s afety and 

pollution pr evention r equirements are be ing m et. T he N ational Potential Incident of 

Noncompliance (PINC) List serves as the baseline for these inspections. The BSEE also inspects 

the stockpiles of equipment listed in the operator's approved Oil Spill Response Plan that would 

be used for the containment and cleanup of hydrocarbon spills.
 

 

The Rig Woodside plans to use will comply with all of the regulations of the American Bureau 

of Shipping (ABS), International Maritime Organization (IMO) and the United States Coast 

Guard (USCG). All drilling operations will be conducted under the provisions of 30 CFR, Part 

250, Subpart D, and other applicable regulations and notices, including those regarding the 

avoidance of potential drilling hazards and safety and pollution prevention control. Such 

measures as inflow detection and well control, monitoring for loss of circulation and seepage 

loss, and casing design will be Woodside’s primary safety measures. Primary pollution 

prevention measures are contaminated and non-contaminated drain system, mud drain system, 

and oily water processing.

(d) Storage Tanks and Production Vessels

Tanks on the Maersk Developer, a typical DP semi, with a capacity of 25 bbls or more of oil as 

defined in 30 CFR 254.6 are listed below:

Type of Storage 

Tank Type of Facility Tank Capacity (bbls)

Number 

of Tanks

Total 

Capacity 

(bbls)

Fluid 

Gravity 

(API)

Hull tanks 1&2 Fuel oil (Diesel) 8204 2 16408 32 o

Hull tanks 3&4 Fuel oil (Diesel) 5500 2 11000 32o

Engine day tank P Fuel oil (Diesel) 305 1 305 32o

Engine day tank S Fuel oil (Diesel) 356 1 356 32o

Settling tank P Fuel oil (Diesel) 213 1 213 32o

Settling tank S Fuel oil (Diesel) 219 1 219 32o

Base oil 1 Lube oil 4838 1 4838 30o

Lubrication oil Lube oil 55 1 55 32o

Waste oil 1&2 Waste oil 226 2 452 31o

(e) Pollution Prevention Measures 

Not applicable. Florida is not an affected State.

(f) Additional Measures

No additional measures are proposed. 
 

 

General Information (§§ 250.213 and 250.243)

(a) Applications and Permits

Application / Permit Issuing Agency Status

APD BSEE District To be submitted

General NPDES Permit U.S. EPA To be submitted

Emergency Evacuation Plan U.S. Coast Guard To be submitted

(b) Drilling Fluids

Type of Drilling Fluid Est. Vol. of Drilling Fluid per Well

Water-based 15,000 bbls

Synthetic-based 10,000 bbls

Oil-Based 0 bbls

(c) Peak Production Rates / Life of Reserves

Not applicable for Exploration Plans.

(d) Oil Characteristics

Not applicable for Exploration Plans.

(e) New or Unusual Technology

Woodside does not propose the use of any new or unusual technology in the activities proposed 

under this plan. Bests and safest technologies as referenced in 30 CF 250 will be incorporated as 

standard operating procedure. 

(f) Bonding Information 

The bond r equirements for the activities and facilities proposed in this Plan are satisfied by an 

area-wide bond furnished and maintained according to 30 CFR Part 256, subpart I and NTL No. 

2000-G16, “Guidelines for General Lease Surety Bonds”; and additional security under 30 CFR 

256.53(d) and National NTL No. 2008-N07, “Supplemental Bond Procedures.” 

(g) Oil Spill Financial Responsibility (OSFR)

Woodside (BOEM Operator No. 02407) will demonstrate oil spill financial responsibility for the 

activities proposed in this Plan according to 30 CFR Part 253, and NTL 2008-N05, “Guidelines

for Oil Spill Financial Responsibility (OSFR) for Covered Facilities”. 
 

 

(h) Deepwater Well Control Statement

Woodside (BOEM Operator N o. 02407) ha s t he f inancial c apability t o drill a r elief w ell a nd 

conduct other emergency well control operations if required. 

(i) Suspensions of Production

Not applicable for Exploration Plans.

(j) Blowout Scenario

A blowout scenario for the proposed operations is outlined in Appendix C. 

(k) Chemical Products

This information is not required for the activities proposed in this plan in the BOEM GOMR.
 

 

Geological Information (§§ 250.214 and 250.244) 

In accordance with 43 C FR 2.13 ( c) (9), those items considered proprietary have been omitted 

from the Public Information copy and have been referenced accordingly. 

(a) Geological Description

The Ivan locations are designed to test the Lower Tertiary Wilcox 1, 2, and 3 zones in WR 325. 

These Paleogene age intervals showed good reservoir quality sand development 6.5 miles to the 

ESE in the nearby Green Bay #1 well (WR 372-1). The Ivan complex is a salt cored anticline 

that extends in a NW to SE fashion beginning in WR 324 in the NW and continuing into WR 

414 and 415 in the SE. The trap consists of 3 way dip closure truncating against the sides of a 

salt keel on the NE side of the structure. The Tucker #1 well (WR 544-1) demonstrates oil 

bearing Wilcox sand development and is approximately 10 miles SW from the location. 

(b) Structure Contour Maps 

Enclosed as Appendix D are cu rrent s tructure m ap(s) drawn t o t he t op of t he proposed 

hydrocarbon z one(s). T he s urface a nd bot tomhole l ocation(s) a long w ith t he l ocations of t he 

geologic cross-sections of the well(s) to be drilled under this EP are included. 

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

Enclosed as Appendix D are copies of the migrated and annotated deep seismic line within 500 

feet of each of the proposed surface locations. 

(d) Geological Structure Cross-Sections 

An interpreted geological cross-section showing the location and depth of each of the proposed 

well(s) with at least one key horizon and the objective sand labeled is enclosed as Appendix D. 

(e) Shallow Hazards Report 

The Shallow Hazard Report was submitted previously with the Initial Exploration Plan.

(f) Site Specific Shallow Hazards Assessment 

Please refer to Appendix E.

(g) High Resolution Seismic Lines 

Please refer to Appendix D.

(h) Stratigraphic Column 

A generalized biostratigraphic/lithostratigraphic c olumn from the seafloor to the total depth of 

each of the proposed well(s) is included as Appendix D. 
 

 

(i) Time Versus Depth Tables 

Time versus depth tables are included as Appendix D.

 

(j) Geochemical Information

This information is not required for the activities proposed in this plan in the BOEM GOMR.

(k) Future G&G Activities

This information is not required for the activities proposed in this plan in the BOEMRE GOMR.
 

 

Hydrogen Sulfide (H2S) Information (§§ 250.215 and 250.245)

(a) Concentration

Woodside does not a nticipate encountering H 2S w hile c onducting our proposed exploratory 

activities.

(b) Classification Request

In accordance with Title 30 CFR 250.490(c), Woodside requests Walker Ridge Block 325, Lease 

OCS-G 32673, be classified by the BOEM as an area where the “absence” of hydrogen sulfide 

has been confirmed based upon the following: 

• T he f ollowing w ells w ere dr illed i n l eases n ear W R 325. N one of the w ells e ncountered 

hydrogen sulfide gas as determined from the available drilling/scout reports and well logs: 

WR-372 #1 OCS-G 18701 Anadarko 

WR-278 #1 OCS-G 18675 Devon 

WR-285 #1 OCS-G 16971 Conoco 

WR-456 #1 OCS-G 16993 Texaco E&P 

WR-456 #1 BP1 OCS-G 16993 Texaco E&P 

WR-456 #1 BP2 OCS-G 16993 Texaco E&P 

WR-544 #1 OCS-G 17003 BP E&P 

WR-508 #1 OCS-G 17001 BP E&P 

WR-508 #2 OCS-G 17001 Shell Offshore 

WR-508 #3 OCS-G 17001 Shell Offshore 

WR-508 #3 BP1 OCS-G 17001 Shell Offshore 

WR-508 #3 BP2 OCS-G 17001 Shell Offshore 

A request for reclassification will be made if additional data indicate that a different 

classification is needed.

 

(c) Contingency Plan 

Woodside does not a nticipate encountering H 2S w hile c onducting our proposed e xploratory 

activities therefore a contingency plan is not required at this time.

(d) Modeling Report

Woodside does not a nticipate encountering H 2S while c onducting our proposed e xploratory 

activities therefore a modeling report is not required at this time.
 

 

Mineral Resource Conservation Information (§ 250.246)

(a) Technology and Reservoir Engineering Practices and Procedures

Not Required for Exploration Plans 

(b) Technology and Recovery Practices and Procedures

Not Required for Exploration Plans 

(c) Reservoir Development

Not Required for Exploration Plans 
 

 

Biological, P hysical, a nd So cioeconomic I nformation ( §§ 2 50.216 

and 250.247)

(a) High Density Deepwater Benthic Communities Information

GEMS performed a geohazards assessment for the “Ivan” Prospect located in Block 325 (OCSG-32673) and vicinity, Walker Ridge Area, Gulf of Mexico using a 3D seismic data volume 

provided by Woodside in November 2008. The purpose of the assessment was to address 

seafloor conditions that may impact exploratory drilling operations within 2000 feet of the 

proposed wellsite. Water depths of the study area are greater than 300 meters (984 feet). No 

high density benthic communities have been reported in the area according to the BOEMRE

(NTL No. 2009-G40). The closest feature with potential for supporting chemosynthetic and 

other deepwater benthic communities is approximately 8,700 ft from the proposed WR 325-D 

location. 

Features or areas that could support high-density chemosynthetic communities are not located 

within 2000 feet of each proposed muds and cuttings discharge location. No anchors will be 

used. 

A S ite C learance Letter can be f ound w ith the S hallow Hazards Assessment i n Appendix E. 

Woodside doe s not a nticipate a ny s eafloor c onditions t hat m ay i mpact e xploratory dr illing 

operations within 2000 feet of the proposed wellsite. 

(b) Topographic Features Map 

There are no proposed bottom-disturbing activities within 1000 feet of the “No Activity Zone” of 

an identified topographic feature. 

(c) Topographic Features Statement (shunting)

The activities proposed in this Plan are in water depths greater than 300 meters so NTL 2009-

G39 is not applicable. 

Woodside does not propose to drill more than two wells from the same surface location which is 

outside t he 1 -mile Zone but w ithin t he P rotective Zone o f a n i dentified t opographic f eature; 

therefore a statement for shunting described in Attachment 2, Section A, Item No. 2 of NTL No. 

2009-G39 “Biologically Sensitive Areas of the Gulf of Mexico” is not required. 

(d) Live Bottom (Pinnacle Trend) Map 

The activities proposed in this plan are not affected by a live bottom (pinnacle trend) stipulation 

attached to the lease.
 

 

(e) Live Bottom (Low Relief) Map 

The a ctivities p roposed in th is p lan a re n ot a ffected b y a liv e b ottom ( low r elief) s tipulation 

attached to the lease.

(f) Potentially Sensitive Biological Features

The activities proposed in this Plan are in water depths greater than 300 meters so NTL 2009-

G39 is not applicable. 

Woodside does not pr opose bot tom-disturbing a ctivities w ithin 6 1 meters ( 200 feet) o f 

potentially sensitive biological features; therefore, the map described in Attachment 8, S ection 

A, of NTL No. 2009-G39 “Biologically Sensitive Underwater Features & Areas” is not required. 

(g) ROV Monitoring Survey Plan

The activities proposed in this plan do not require an ROV Survey Plan since the Deepwater Grid 

(Grid N o. 1 1) accessed t hrough N TL 2008 -G06 s hows s ufficient R OV information ha s b een 

gathered for this block. 

(h) Threatened and Endangered Species Information

The Marine Mammal Protection Act (MMPA) established a moratorium on the taking of marine 

mammals in U.S. waters. It defines “take” to mean “to hunt, harass, capture, or kill” any marine 

mammal, or attempt to do so. Marine mammals protected under the MMAP that may be found 

in the location of the activities proposed include: 

Sperm Whales, Blue Whales, Sei W hales, Fin Whales, Humpback Whales and N orth A tlantic

Right Whales - of these six whales, only Sperm Whales are considered to commonly occur in the 

Gulf of M exico. Non-endagered s pecies i nclude the B ryde’s w hale, m inke w hale, p ygmy and 

dwarf sperm whale and beaked whales. The West Indian manatee is the only sirenian occurring 

in the Gulf of Mexico. Bottlenose, Atlantic Spotted, Clymene, Fraser’s, rough-toothed, spinner 

and striped dolphins as well as false killer, killer, pygmy killer, melon-headed and short-finned 

pilot whales.

The pur pose of t he E ndangered S pecies A ct ( ESA) i s t o c onserve t hreatened a nd e ndangered 

species and their ecosystems. A species is considered endangered if it is in danger of extinction 

throughout a ll or a s ignificant por tion of i ts r ange. A s pecies i s co nsidered t hreatened i f i t i s 

likely t o become endangered in the future. The l ocation of the activities proposed in this plan 

does not i nclude a ny c ritical ha bitats de signated unde r t he E SA. Threatened an d en dangered 

turtles that may be found in the location of the activities proposed include: 
 

 

Green Sea Turtles, Hawk’s Bill Sea Turtles, Kemp’s Ridley Sea Turtles, Leatherback Sea

Turtles, and Loggerhead Sea Turtles. 

Other threatened or endangered species or “species of concern” (i.e., a candidate for Federal 

listing under the ESA) that have been identified by the NMFS as potentially sensitive to OCS 

activities within the Gulf of Mexico include: 

Gulf sturgeon, smalltooth sawfish, southern bald eagle, eastern brown pelican, Eskimo curlew, 

piping plover, southeastern snowy plover, roseate tern, whooping crane and wood stork as well 

as four subspecies of beach mice 

Threatened nearshore marine invertebrates species include: 

Elkhorn Coral and Staghorn Coral 

Please refer to our Environmental Impact Analysis (EIA) contained in this plan for detailed 

information on how Woodside plans to mitigate harm to these threatened and endangered 

species.

(i) Archaeological Report

Woodside will perform an ROV/AUV survey imaging 100% of the seafloor with sector scanning 

sonar within a minimum 500’ radius of the proposed well location(s) prior to or upon 

commencement of operations. These locations will be certified by an authorized marine

archaeologist and by Woodside to be clear of seafloor archaeological resources, including 

historic shipwrecks. Copies of the certifications and a circle radius plat of the survey area will be 

submitted to the BOEMRE. Should a resource be encountered, Woodside will contact the 

BOEMRE immediately.

 

(j) Air and Water Quality Information

The location of the activities proposed in this plan does not affect the State of Florida; therefore 

this information is not required in this plan. 

(k) Socioeconomic Information

The location of the activities proposed in this plan does not affect the State of Florida; therefore 

this information is not required in this plan. 
 

 

Waste and Discharge Information (§§ 250.217 and 250.248)

(a) Projected Ocean Discharges See Table 1 below. There will be do downhole disposal. 

These discharges will be covered by a general NPDES discharge permit.

(b) Projected Generated Wastes See Table 2 below

Table 1. Wastes Generated, Treated and Downhole Disposed or Discharged to the Gulf of 

Mexico (Discharges Per Well Unless Otherwise Noted)

Projected Generated Waste Projected Ocean Discharges

Type of Waste and 

Composition

Composition Projected 

Amount

Maximum 

Discharge Rate

Discharge Method

Water-Based 

Drilling Fluid

Barite, 

additives

15000 bbls 3000 bbls/mo Discharged Overboard

Synthetic- based 

Drilling fluid

Esters, 

polyalpha 

olefins

NA NA NA

Cuttings Wetted 

with Syntheticbased Fluid

Esters, 

polyalpha 

olefins

5700 bbls 1140 bbls/mo. Cleaned & Discharged 

Overboard 

Cuttings Wetted 

with Water-Based 

Fluid

Barite, 

additives 

530 bbls 16 bbls/mo. Discharged Overboard

Cuttings Wetted 

with Oil- based Fluid

Diesel 0 NA NA

Domestic Waste Grey water 730,000

gal.

35 

gal/person/day

Treated and Discharged 

Overboard

Sanitary Waste Treated 

Sanitary 

Waste

517,500 

gal.

25 

gal/day/person

“ “

Deck Drainage Rain/Wash 

Water

0-100,000 

bbls / 

rainfall

NA “ “

Well Treat., W/O or 

Completion Fluids

NA NA Discharged Overboard

Desalinization unit Brine 16,500 bbls 110 bbls/day “ “

BOP fluid BOP Fluid 35 bbls/yr 3 bbls/mo. Discharged at seafloor

Ballast Water NA NA Discharged Overboard

Bilge water NA NA “ “

Excess cement at 

seafloor

Cement 700 bbls 140 bbls/mo. Discharged at seafloor

Fire water NA NA Discharged Overboard

Cooling water NA NA “ “

Produced Water NA NA “ “

NA=Not Applicable 
 

 

Table 2. Wastes Transported and/or Disposed of Onshore (Discharges Per Well 

Unless Otherwise Noted)

Projected Generated 

Waste 

Solid and 

Liquid Wastes 

Transportation

Waste Disposal

Type of 

Waste

Composition Transport 

Method

Name/Location 

of Facility

Amount Disposal 

Method

Oil-Based 

Fluid

NA

Syntheticbased 

Fluid

Used SBF 

and additives 

Tanks on 

supply boat 

US Liquids, 

Fouchon, LA

10,000 

bbls/well

Recycled

Cuttings 

Wetted 

with OilBased Mud

NA

Produced 

Sand

NA

Trash and 

Debris

Steel, cables, 

paper, 

cardboard, 

plastic

Storage bins on 

supply boat 

Waste 

Management 

Galliano, LA

23.3 cu. 

meter/yr

Landfill

Used Oil Used oil Drums on 

supply boat

New Park 

Fourchon, LA

20 

bbls/yr

Recycled

Wash 

Water

NA

Chemical 

Wastes

NA

NA=Not Applicable

(c) Modeling Report

Not required by EPA under the OCS General Permit. 

(d) NPDES Permits

This information is not required for the activities proposed in this plan in the BOEM GOMR.

Any discharges will be performed in accordance with GMG 290,000. 

(e) Cooling Water Intakes

This information is not required for the activities proposed in this plan in the BOEM GOMR.
 

 

Air Emissions Information (§§ 250.218 and 250.249)

(a) Screening Checklist

Included in this section is the Projected Air Emissions Worksheet prepared in accordance with 

NTL No. 2008-G04. 

For th is p lan, th ere are n o existing f acilities o r activities co-located w ith t he c urrent pr oposed 

activities; therefore, the Complex Total Emissions are the same as the Plan Emissions.

Screening Questions for EP’s Yes No

Is any calculated Complex Total (CT) Emission amount (tons) associated with your 

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

following formulas: CT = 3400D2/3 for CO, and CT = 33.3D for the other air 

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

x

Do your emission calculations include any emission reduction measures or modified 

emission factors?

x

Are your proposed exploration activities located east of 87.5o W longitude? x

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

(ppm)?

x

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

any proposed well?

x

Do you propose to burn produced hydrocarbon liquids? x

Air Pollutant

Plan 

Emission 

Amounts1 

(tons)

Calculated 

Exemption 

Amounts2 

(tons)

Calculated

Complex Total 

Emission Amounts3 

(tons)

Carbon monoxide (CO)

SEE ATTACHED APPENDIX F 

NA

Particulate matter (PM) NA

Sulphur dioxide (SO2) NA

Nitrogen oxides (NOx) NA

Volatile organic compounds 

(VOC)

NA

1 For activities proposed in your EP or DOCD, list the projected emissions calculated from the worksheets.

2 List the exemption amounts for your proposed activities calculated by using the formulas in 30 CFR 250.303(d). 

3 List the complex total emissions associated with your proposed activities calculated from the worksheets

Calculations of the projected Plan Emission, Complex Total Emission and Exemption Amounts 

were performed by Debra K. Benoit, (713) 401-0083, Debra.benoit@Woodsideenergy.com
 

 

Oil Spills Information (§§ 250.219 and 250.250)

(a) Oil Spill Response Planning

(1) Site-Specific OSRP

Not applicable. This Plan is not for the Eastern Planning Area and Florida is not an 

affected state.

(2)(i) Regional or Subregional OSRP Information

Woodside’s Regional Oil Spill Response Plan (OSRP) (BOEMRE Operator No. 02407) 

has been revised and submitted for approval on May 19, 2011. The Regional OSRP will 

cover activities proposed in this Plan. OSRP Certification is detailed in Appendix G. 

(ii) Spill Response Sites 

Primary Response Equipment Location Preplanned Staging Location(s)

Lake Charles and Fourchon, LA Fourchon, LA

(iii) OSRO Information

 Woodside’s p rimary response providers, Clean Gu lf As sociates ( CGA), N ational 

Response C orporation ( NRC) Helix W ell C ontainment G roup ( HWCG) and O’Brien’s 

Response Management (ORM), will provide closest available personnel and equipment, 

as well as supervisory personnel. 

(iv) Worst Case Scenario Determination

Category Regional OSRP EP 

Type of Activity Exploratory Drilling Exploratory Drilling

Facility Location (area/block) AT 187* WR 325

Facility Designation2 Wellbore Wellbore

Distance to Nearest Shoreline (miles) 79 165 

Volume3

Storage tanks (total)

Flowlines (on facility)

Lease term pipelines

Uncontrolled blowout (volume per 

day)

Total Volume

NA

NA

NA

199,028 bbls 

199,028 bbls

NA

NA

NA

31,190 bbls 

31,190 bbls

Type of Oil(s) (crude oil, condensate, 

diesel)

Crude Oil Crude Oil

API Gravity(s)4 28o 24o

*

(BOEM Control No. N-9534) 
 

 

1 Types of activities include pipeline, platform, caisson, subsea completion or manifold, and mobile drilling rig. 2 E.g., Well No. 2, Platform JA, Pipeline Segment No. 6373.

3

 Take your regional OSRP worst-case scenario volume from the appropriate section of your regional OSRP. For 

EP’s, the worst-case scenario volume is the daily volume possible from an uncontrolled blowout. Determine this 

volume using the provisions of 30 CFR 254.47(b). For DOCD’s, determine the volume of your worst-case 

scenario using the provisions of 30 CFR 254.47(a), (b), and (c), as appropriate. 4

 Provide API gravity of all oils given under “Type of Oil(s)” above. Estimate for EP’s.

Since Woodside has the ability to respond to the appropriate worst-case spill scenario included in 

its regional OSRP submitted May 19, 2011 and since the worst-case scenario determined for this 

Plan does not replace the worst-case scenario in our regional OSRP, I hereby certify that

Woodside has the capability to respond, to the maximum extent practicable, to a worst-case 

discharge, or a substantial threat of such a discharge, resulting from the activities proposed in 

this Plan.

The a ssumptions a nd calculations f or t he W CD f or t he pr oposed ope rations a re de tailed i n 

Appendix C. 

(b) Oil Spill Response Discussion

The oil spill response discussion for the proposed operations is detailed in Appendix G.

(c) Modeling Report

Not applicable. Florida is not an affected State. No installation of surface facilities is planned 

located in water depths greater than 400 meters. 
 

 

Environmental Monitoring Information (§§ 250.221 and 250.252)

(a) Monitoring Systems

Woodside is aware of the requirements of NTL No. 2009-G02 whereby BOEM established and 

implemented a program to monitor ocean currents and require operators to share the data for all 

floating MODU’s and production facilities operating or installed in water depths greater than 400 

meters (1,312 feet). Woodside will report ocean current data to the National Data Buoy Center 

(NDBC) Internet website as required. 

(b) Incidental Takes 

Woodside does not anticipate the incidental taking of any protected species or marine mammal 

as a result of the activities proposed in this Plan based on the implementation of, and adherence 

to, NTL No . 2012-Joint-G02 “Implementation o f S eismic S urvey M itigation M easures a nd 

Protected S pecies O bserver P rogram, NTL No . 2012-BSEE-G01 “Marine T rash an d D ebris 

Awareness Training and Elimination” and NTL No. 2012-Joint-G01 “Vessel Strike Avoidance 

and Injured/Dead Protected Species Reporting”.

(c) Flower Garden Banks National Marine Sanctuary

Woodside’s activities under this Supplemental EP are not located within the Protective Zones of 

the Flower Garden Banks or Stetson Bank; therefore, are not required to monitor the impacts of 

an oil spill that may affect these areas. 
 

 

Lease Stipulations Information (§§ 250.222 and 250.253)

Oil a nd gas e xploration a nd d evelopment activities on t he OCS a re s ubject t o s tipulations 

developed before the lease sale and would be attached to the lease instrument, as necessary, in 

the form o f mitigating measures. The BOEM is responsible for ensuring full compliance with 

stipulations. 

BOEM (Minerals M anagement S ervice) invoked The P rotected S pecies S tipulation for L ease 

OCS-G 32673, Walker Ridge Block 325. 

The Protected Species Stipulation was invoked to reduce the potential taking of federally

protected s pecies ( e.g., sea t urtles, m arine m ammals an d o ther l isted s pecies in t he 

Endangered Species Act of 1973 (ESA).

Bureau of S afety and Environmental E nforcement ( BSEE) [BOEMRE] issued N TL 

2012-Joint-G01 and N TL 2012-Joint-G02 pursuant t o 30 C FR 250.103, 250.23( o) a nd 

250.204(s) to explain how Operators must implement measures to minimize the risk of 

vessel s trikes t o pr otected s pecies a nd report obs ervations of i njured o r d ead pr otected 

species e ffective F ebruary 7, 2007. Woodside will e nsure t hat our c ontract ve ssel 

operators ar e aw are o f t heir requirement t o r eport s ightings of a ny i njured or de ad 

protected species immediately to the BOEM Protected Species Biologist by telephone. 

The Bureau of S afety and E nvironmental E nforcement ( BSEE) (formerly BOEMRE) 

issued NTL 2012-BSEE-G01 pursuant to 30 CFR 150.103 to provide guidance and assist 

the operators in preventing intentional and / or accidental introduction of trash and debris 

into th e ma rine e nvironment. W ith th is a ssistance a nd with la ws s uch a s M ARPOLAnnex V , t he M arine Plastic P ollution Research a nd C ontrol A ct, and r egulations 

imposed by various agencies including the U.S. Coast Guard and the U.S. Environmental 

Protection A gency, ou r e mployees w ill e nsure t hat a ll of fshore pe rsonnel, i ncluding 

contractors and other support services-related personnel have complete understanding of 

the r equirement t hat O perators be pr oactive i n avoiding a ccidental l oss of s olid w aste 

items on the OCS.
 

 

Environmental Mitigation Measures Information (§§ 250.223 and 

250.254)

(a) Mitigation of Impacts. 

Not applicable. Florida is not an affected State. 

(b) Incidental Takes 

Woodside does not anticipate the incidental taking of any protected species or marine mammal 

as a result of the activities proposed in this Plan based on the implementation of, and adherence 

to, N TL N o. 2012-Joint-G02 “Implementation o f S eismic S urvey M itigation M easures a nd 

Protected S pecies O bserver P rogram, N TL No. 2012-BSEE-G01 “Marine T rash an d D ebris 

Awareness Training and Elimination” and NTL No. 2012-Joint-G01 “Vessel Strike Avoidance 

and Injured/Dead Protected Species Reporting”.

Decommissioning Information (§ 250.255)

Not applicable. The information at § 250.255 regarding decommissioning is not required to 

accompany EP’s and DOCD’s submitted in the MMS GOMR. 

Related Facilities and Operations Information (§ 250.256)

(a) Related OCS Facilities and Operations

 This discussion is not required for EP’s. 

(b) Transportation System

 This discussion is not required for EP’s. 

(c) Produced Liquid Hydrocarbons Transportation Vessels

There will be no produced liquid hydrocarbons, including well test fluids, transported by 

means other than a pipeline for the activities proposed in this plan. 
 

 

Support Vessels and Aircraft Information (§§ 250.224 and 250.257)

(a) General

The following list provides information regarding the vessels and aircraft Woodside will use to 

support our proposed activities. 

Type of Vessel

Maximum Fuel 

Tank Storage 

Capacity

Maximum No. in 

Area at Any 

Time

Trip Frequency or 

Duration 

Tug boat(s) N/A N/A N/A

Supply boat(s) 250,000 gals 2 3 times / week

Anchor boat(s) NA NA NA

Crew boat(s) 34,000 gals 1 6 times / week

Helicopter 280 gals 1 6 times / week

(b) Diesel Oil Supply Vessels

Not a pplicable. Florida is n ot a n affected s tate; n o a ctivities a re p roposed w ithin P rotective 

zones; no surface facility is planned in water depths greater than 400 meters or a surface facility 

in any water depth that supports a subsea development in water depths greater than 400 m eters 

(1,312 feet); this is not a DOCD for which Alabama is an affected state or a D OCD proposing 

new multiwell structures for which Louisiana is an affected state. 

Size of Fuel Supply 

vessel

Capacity of fuel 

supply vessel

Frequency of fuel 

transfers

Route fuel supply 

vessel will take

285’ 203,000 gal. Weekly Fourchon to MODU

(c) Drilling Fluids Transportation

Type of Material 

Quantity Being 

Transported

Quantity Being 

Transported

Transportation Method

Dry Bulk (Cement,

Barite, Gel)

12,000 sx max combined Below deck dry bulk tanks

onboard OSV 

Synthetic-base drilling

fluids 

11,000 bbls max per 

voyage 

Drums on supply boat

Water Based drilling

fluids 

12,000 bbls max per 

voyage 

Below deck liquid mud

tanks onboard OSV 

(d) Solid and Liquid Wastes Transportation

See Table 2 of Waste and Discharge Section. 
 

 

(e) Vicinity Map

A Vicinity Plat showing the location of Walker Ridge Block 325 relative to the shoreline and the 

onshore base is included as Appendix E. 
 

 

Onshore Support Facilities Information (§§ 250.225 and 250.258)

(a) General

Woodside proposes to utilize the following existing onshore base for support: 

Name Location Existing, New or 

Modified

Baker Hughes 

Drilling Fluids Fourchon, LA Existing

C-Port Fourchon, LA Existing

(b) Support Base Construction or Expansion

The pr oposed ope rations do not m andate a ny immediate m easures f or l and a cquisition or 

expansion of the existing onshore base facilities. 

(c) Support Base Construction or Expansion Timetable 

No known shore base construction is planned for the time period of this operation. 

(d) Waste Disposal

See Table 2 of Waste and Discharge Section. 

 

(e) Air Emissions

This discussion is not required to accompany EP’s submitted in the BOEM GOMR.

(f) Unusual Solid and Liquid Wastes

This discussion is not required to accompany EP’s submitted in the BOEM GOMR.

Sulfur Operations Information (§ 250.259)

Woodside is not proposing to conduct sulfur operations in this Plan.
 

 

Coastal Zone Management Act (CZMA) Information (§§ 250.226 

and 250.260)

The S tates o f T exas, L ouisiana, M ississippi, A labama, a nd F lorida ha ve f ederally a pproved 

coastal z one m anagement pr ograms ( CZMP). Applicants f or an O CS plan s ubmitted t o t he 

BOEM must provide a certification with necessary data and information for the affected State to 

determine t hat the p roposed act ivity(s) co mplies w ith t he en forceable p olicies o f each S tates’ 

approved p rogram, and that s uch a ctivity will be c onducted i n a m anner c onsistent w ith t he 

program. 

(a) Consistency Certification

A Coastal Zone Management Consistency Certification for the State of Louisiana is required for 

the initial exploratory activities proposed in this plan and is included in Appendix H. 

Consistency certification is not required because when a Plan is not 

(1) Initial EP or DOCD 

(2) Supplemental EP or DOCD for which Florida and Alabama are affected States

(3) Supplemental DOCD proposing new multi-well structures for which Louisiana, Mississippi, 

and Texas are affected States 

(4) Revised EP or DOCD for which the MMS GOMR determines that the revisions could result 

in a significant change in the impacts previously identified and evaluated (refer to 30 

CFR 250.285). 

(b) Other Information

The enforceable policies for the State of Louisiana were considered in making the certification of 

consistency above.

Environmental Impact Analysis (EIA) (§§ 250.227 and 250.261)

The Environmental Impact Analysis is included as Appendix H.
 

 

Administrative Information (§§ 250.228 and 250.262)

NTL 2010 -N10 S tatement of C ompliance w ith A pplicable R egulations a nd Evaluation of 

Information Demonstrating Adequate Spill Response and Well Containment Resources 

NTL 2010- N06 Information Requirements for EPs, DPPs, and DOCDs on the OCS. 

3D GeoHazard Study of Block 325, Walker Ridge Area, OCS-G 32673 prepared for Woodside. 

NTL 2009-G40 Benthic Communities

NTL 2009-G39 Biologically Sensitive Underwater Features & Areas 

NTL 2009 -G27 & 20 10-N06 Submitting E xploration P lans & D evelopment O perations 

Coordination Documents 

NTL 2009-G06 Military Warning and Water Test Areas.

NTL 2009-G02 Ocean Current Monitoring 

NTL 2008 -G20 & 201 2-Joint-G01 Revisions t o t he List of O CS Lease Blocks R equiring 

Archaeological Resource Surveys and Reports. 

NTL 2008-N07 Supplemental Bond Procedures. 

NTL 2008-N05 Guidelines for Oil Spill Financial Responsibility (OSFR) for Covered Facilities.

NTL 2008-G06 Remotely Operated Vehicle Surveys in Deepwater.

NTL 2008 -G04 Information R equirements f or E xploration Plans a nd D evelopment O perations 

Coordination Documents. 

NTL 2012-Joint-G01 Vessel Strike Avoidance and Injured/Dead Protected Species Reporting. 

NTL 2012-BSEE-G01 Marine Trash and Debris Awareness and Elimination.

NTL 2012-Joint-G01 Implementation of S eismic S urvey M itigation M easures a nd P rotected 

Species Observer Program

NTL 2005-G07 Archaeological Resource Surveys and Reports. 

NTL 2001-G10 Clarification of Eastern Gulf of Mexico Sale 181 Military Areas Stipulation.

NTL 2000-G16 Guidelines for General Lease Surety Bonds. 

Current Code of Federal Regulations 30 Parts 250, 254 and 256. 
 

 

ADMINISTRATIVE INFORMATION

(a) Exempted Information Description (Public Information Copies Only)

In accordance with 43 CFR Part 2, Appendix E, sections (4) and (9), the following information is 

exempt from disclosure and has been omitted from the Public Information copy of this plan: 

• The geologic objectives, BHL, TVD, and MD information on form BOEM-137 (OCS 

Plan Information Form) in Appendix A 

• All items under Geological and Geophysical Information, except for the non-proprietary 

version of shallow hazards assessment

• Correlative well information used to justify H2S classification request under Hydrogen 

Sulfide Information 

• Geological section of Worst Case Discharge Scenario calculations and assumptions.

(b) Bibliography

• Shallow Hazard Survey 

• Woodside Oil Spill Response Plan

• Outer Continental Shelf Oil & Gas Leasing Program: 2007-2012, Final Environmental 

Impact Statement, 2007-03 

• Initial Exploration Plan N-9414 
 

 

Appendix A

Plan Information Form 
U.S. Department of the Interior

Bureau of Ocean Energy Management

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

Company Name: Woodside Energy (USA), Inc. BOEM Operator Number: 02407

Address: 5151 San Felipe Street Contact Person: Ann Hebert

Suite 1200 Phone Number: (713) 401-0019

Houston, Texas 77056 Email Address: Ann.Hebert@WoodsideEnergy.com

If a service fee is required under Amount Paid Receipt No.

30 CFR 250.125 (a) provide the NA

Lease(s): Area Block(s) Project Name (if applicable)

WR 325 Ivan

Objective(s) X Oil Gas Sulphur Salt Onshore Support Base(s): Fourchon, LA

Platform/Well Name: B Total Volume of WCD: 13205 stbbls API Gravity: 24 °

Distance Closest to Land (Miles): 165 Volume from Uncontrolled Blowout: 1.5MMstb

Have you previously provided information to verify the calculations and assumptions for your WCD? Yes No X

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 x

Do you propose to use a vessel with anchors to install or modify a structure? Yes No x

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

Jack Up Drill Ship Caisson Tension Leg Platform

Gorilla Jack Up Platform Rig Fixed Platform Compliant Tower

Semisubmersible Submersible Spar Guyed Tower

DP Semisubmersible X Other Floating Other

(Attach description) Production System (Attach description)

Drilling Rig Name (If Known):

Form BOEM-0137 (December 2011 - Supersedes all previous editions of this form which may not be used.)

Page 1 of 7

Description of Proposed Activites and Tentative Schedule (Mark all that apply)

From (Facility /Area/Block) To (Facility /Area/Block) Diameter Length (feet)

OCS PLAN INFORMATION FORM

OMB Control Number: 1010-0151

OMB Approval Expires: 12/31/14

General Information

Project and Worst Case Discharge (WCD) Information

Description of Lease Term Pipelines

Proposed Activity End Date No. of Days

Description of Drilling Rig Description of Structure

OCS-G-32673

Exploration Drilling #A 1/1/2013 5/31/2013 151

Exploration Drilling #B

Start Date

1/1/2014 5/31/2014 151

Exploration Drilling #C 1/1/2015 5/31/2015 151

Exploration Drilling #D 1/1/2016 5/31/2016 152
Well or Structure Name/Number (if renaming Previously reviewed under an approved EP or DOCD?

 well or structure, reference previous name) A Yes X No

Is this an existing well or If this is an existing well or structure,

structure? Yes No X 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 X No

WCD Info For wells, volume of uncontrolled For structures, volume of all storage and API Gravity of 

blowout (bbls/day): 12154 stb/d pipelines: fluid 24

Surface Location Bottom-Hole Location (for Wells) Completion (for multiple completions enter separate lines

Lease No. OCS G-32673 OCS OCS

OCS

Area Name WR

Block No. 325 N/S Departure F___L

Blockline N/S Departure 1479' FSL N/S Departure F___L

Departures E/W Departure 1202' FEL E/W Departure E/W Departure F___L

(in feet) F___L

(in feet) X: 2,263,918' X: X:

Lambert X:

X-Y Y: 9,663,879' Y: Y:

Coordinates Y:

Latitude/ Latitude: 26° 37' 10.539" Latitude: Latitude:

Longitude Latitide:

Longitude: -91° 05' 28.180" Longitude: Longitude:

Longitude:

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

6343' MD (Feet): TVD (Feet):

Anchor Radius (if applicable) in feet: NA

Anchor Name

or Number

Form BOEM-0137 (December 2011 - Supersedes all previous editions of this form which may not be used.)

Page 2 of 7

X= Y=

X= Y=

X= Y=

X= Y=

X= Y=

X= Y=

X= Y=

X= Y=

X= Y=

X= Y=

Anchor Locations for Drilling Rig or Construction Barge (if anchor radius supplied above, not necessary)

Area Block X Coordinate Y Coordinate Length of Anchor Chain on Seafloor

Y=

X= Y=

X=

Include one copy of this page for each proposed well/structure

Proposed Well/Structure Location

OCS PLAN INFORMATION FORM (CONTINUED)
Well or Structure Name/Number (if renaming Previously reviewed under an approved EP or DOCD?

 well or structure, reference previous name) B Yes X No

Is this an existing well or If this is an existing well or structure,

structure? Yes No X 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 X No

WCD Info For wells, volume of uncontrolled For structures, volume of all storage and API Gravity of 

blowout (bbls/day): 13205 stb/d pipelines: fluid 24

Surface Location Bottom-Hole Location (for Wells) Completion (for multiple completions enter separate lines

Lease No. OCS G-32673 OCS OCS

OCS

Area Name WR

Block No. 325 N/S Departure F___L

Blockline N/S Departure 2186' FSL N/S Departure F___L

Departures E/W Departure 1909' FEL E/W Departure E/W Departure F___L

(in feet) F___L

(in feet) X: 2,263,211' X: X:

Lambert X:

X-Y Y: 9,664,586' Y: Y:

Coordinates Y:

Latitude/ Latitude: 26° 37' 17.644" Latitude: Latitude:

Longitude Latitide:

Longitude: -91° 05' 35.852" Longitude: Longitude:

Longitude:

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

6334' MD (Feet): TVD (Feet):

Anchor Radius (if applicable) in feet: NA

Anchor Name

or Number

Form BOEM-0137 (December 2011 - Supersedes all previous editions of this form which may not be used.)

Page 3 of 7

Y=

X= Y=

X= Y=

X= Y=

X=

X= Y=

X= Y=

X= Y=

X= Y=

X= Y=

Include one copy of this page for each proposed well/structure

OCS PLAN INFORMATION FORM (CONTINUED)

Proposed Well/Structure Location

Anchor Locations for Drilling Rig or Construction Barge (if anchor radius supplied above, not necessary)

Area Block X Coordinate Y Coordinate Length of Anchor Chain on Seafloor

X= Y=

X= Y=

X= Y=
Well or Structure Name/Number (if renaming Previously reviewed under an approved EP or DOCD?

 well or structure, reference previous name) C Yes X No

Is this an existing well or If this is an existing well or structure,

structure? Yes No X 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 X No

WCD Info For wells, volume of uncontrolled For structures, volume of all storage and API Gravity of 

blowout (bbls/day): 12821 stb/d pipelines: fluid 24

Surface Location Bottom-Hole Location (for Wells) Completion (for multiple completions enter separate lines

Lease No. OCS G-32673 OCS G-32673 OCS

OCS

Area Name WR WR

Block No. 325 325 N/S Departure F___L

Blockline N/S Departure 2445' FSL N/S Departure F___L

Departures E/W Departure 943' FEL E/W Departure E/W Departure F___L

(in feet) F___L

(in feet) X: 2,264,177' X: X:

Lambert X:

X-Y Y: 9,664,845' Y: Y:

Coordinates Y:

Latitude/ Latitude: 26° 37' 20.066" Latitude: Latitude:

Longitude Latitide:

Longitude: -91° 05' 25.167" Longitude: Longitude:

Longitude:

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

6350' MD (Feet): TVD (Feet):

Anchor Radius (if applicable) in feet: NA

Anchor Name

or Number

Form BOEM-0137 (December 2011 - Supersedes all previous editions of this form which may not be used.)

Page 4 of 7

Area Block X Coordinate Y Coordinate Length of Anchor Chain on Seafloor

X= Y=

OCS PLAN INFORMATION FORM (CONTINUED)

Include one copy of this page for each proposed well/structure

Proposed Well/Structure Location

Anchor Locations for Drilling Rig or Construction Barge (if anchor radius supplied above, not necessary)

X= Y=

X= Y=

X= Y=

X= Y=

X= Y=

X= Y=

X= Y=

X= Y=

X= Y=

X= Y=

X= Y=
Well or Structure Name/Number (if renaming Previously reviewed under an approved EP or DOCD?

 well or structure, reference previous name) D Yes No X

Is this an existing well or If this is an existing well or structure,

structure? Yes No X 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 X No

WCD Info For wells, volume of uncontrolled For structures, volume of all storage and API Gravity of 

blowout (bbls/day): 11760 stb/d pipelines: fluid 24

Surface Location Bottom-Hole Location (for Wells) Completion (for multiple completions enter separate lines

Lease No. OCS G-32673 OCS OCS

OCS

Area Name WR

Block No. 325 N/S Departure F___L

Blockline N/S Departure 1683' FSL N/S Departure F___L

Departures E/W Departure 736' FEL E/W Departure E/W Departure F___L

(in feet) F___L

(in feet) X: 2,264,384' X: X:

Lambert X:

X-Y Y: 9,664,083' Y: Y:

Coordinates Y:

Latitude/ Latitude: 26° 37' 12" Latitude: Latitude:

Longitude Latitide:

Longitude: -91° 05' 23" Longitude: Longitude:

Longitude:

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

6346' MD (Feet): TVD (Feet):

Anchor Radius (if applicable) in feet: NA

Anchor Name

or Number

Form BOEM-0137 (December 2011 - Supersedes all previous editions of this form which may not be used.)

Page 5 of 7

OCS PLAN INFORMATION FORM (CONTINUED)

Include one copy of this page for each proposed well/structure

Proposed Well/Structure Location

Anchor Locations for Drilling Rig or Construction Barge (if anchor radius supplied above, not necessary)

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=

X= Y=

X= Y=

X= Y=

X= Y=
Analog Wells

GEOLOGIC DATA FOR WCD

Hole Interval for WCD

 Top (TVD in feet)

Formation Data Sand 5

Sand Name

Estimated Top TVD

Estimated Base TVD

Estimated Net Sand Height MD

(Net Pay if Hydrocarbon)

Estimated Net Sand Height TVD

(Net Pay if Hydrocarbon)

Fluid Type

Used in WCD? (Yes/No)

Seismic Survey Used

NA

ENGINEERING DATA FOR WCD

WCD Engineering Items

WCD (STB/Day)

WCD Calculated at Mudline Yes No Yes No

Flow Correlation

Outlet Pressure (psia)

Gas Turbulence Factor

Software Model Used

Formation Data Sand 5

Sand Name

Permeability (mD)

Initial Pressure (psia)

Form BOEM-0137 (December 2011 - Supersedes all previous editions of this form which may not be used.) Page 6 of 7

Sand 1 Sand 2 Sand 3 Sand 4 Sand 6

Atmosphere

Base (TVD in feet)

Sand 1 Sand 2 Sand 3 Sand 4 Sand 6

OCS PLAN INFORMATION FORM (CONTINUED)
Formation Data Sand 5

Reservoir Temperature (F)

Porosity (0.00)

Water Saturation (0.00)

Rock Compressability (microsips)

Water Salinity (ppm)

Drive Mechanism

Drainage Area (acres)

Oil Reservoir Data Sand 5

Bubble Point Pressure (psia)

Initial Bo (RB/STB)

Bo (RB/STB) @ Bubble Point

Rsi (SCF/STB)

Initial Oil Viscosity (Cp)

Oil Viscosity (Cp) @ Bubble Point

Oil Compressability (1 psia)

Oil API Gravity (API)

Specific Gas Gravity (0.00)

Gas Reservoir Data Sand 5

Condensate API Gravity (API)

Specific Gas Gravity (0.00)

Yield (STB/MMCF

Source of Permeability Used

Permeability from MDT

Permeability from Core Anlaysis

Pressure Transient Analysis

Permeability from CMR or NMR log analysis

Permeability from other source.

Provide Model Input Values for Relative Permeability

Residual Oil to Gas Fraction (=1-Slc-Swe)

Residual Oil to Water Fraction (=Soc)

Critical Gas Fraction (Sge. Gas/Oil-Water Systems

Residual Gas to Water Fraction (Sge, Gas/Gas-Water Systems)

Kro Oil Curve Endpoint (fraction of absolute permeability)

Krg Gas Curve Endpoint (fraction of absolute permeability)

Krw Water Curve Endpoint (fraction of absolute permeability)

Form BOEM- 0137 (December 2011- Supersedes all previous editions of this form which may not be used.) Page 7 of 7

Percussion Core Rotary Sidewall Core Conventional Core

Sand 1 Sand 2 Sand 3 Sand 4 Sand 6

Sand 1 Sand 2 Sand 3 Sand 4 Sand 6

Sand 1 Sand 2 Sand 3 Sand 4 Sand 6

OCS PLAN INFORMATION FORM (CONTINUED)

Paperwork Reduction Act of 1995 Statement: The Paperwork Reduction Act of 1995 (44 U.S.C. 2501 et seq.) requires us to inform you that BOEM collects this 

information as part of an applicant’s Exploration Plan or Development Operations Coordination Document submitted for BOEM approval. We use the information to 

facilitate our review and data entry for OCS plans. We will protect proprietary data according to the Freedom of Information Act and 30 CFR 550.197. An agency may 

not conduct or sponsor, and a person is not required to respond to, a collection of information unless it displays a currently valid Office of Management and Budget 

Control Number. Responses are mandatory (43 U.S.C. 1334). The public reporting burden for this form is included in the burden for preparing Exploration Plans and 

Development Operations Coordination Documents. We estimate that burden to average 600 hours with an accompanying EP, or 700 hours with an accompanying DPP 

or DOCD, including the time for reviewing instructions, gathering and maintaining data, and completing and reviewing the forms associated with subpart B. Direct 

comments regarding the burden estimate or any other aspect of this form to the Information Collection Clearance Officer, Bureau of Ocean Energy Management, 381 

Elden Street, Herndon, VA 20170.
 

 

Appendix B 

Vicinity Map

Location /

Bathymetry Map







 

 

Appendix C 

Blowout Scenario

WCD Assumptions and Calculations
Blowout Scenario 

1) Purpose. 

Pursuant with 30 CFR 250.213(g), 250.219, 250.250 and NTL No. 2010-N06, this 

provides a blowout scenario description, further information regarding any potential 

oil spill, the assumptions and calculations used to determine the worst case discharge 

and the measures taken to firstly enhance the ability to prevent a blowout and 

secondly to respond and manage a blowout scenario if it occurred. 

2) Background. 

This attachment has been developed to document the additional information 

requirements for Exploration Plans as requested by NTL No. 2010-N06 in response to 

the explosion and sinking of the Mobile Offshore Drilling Unit (MODU) ‘Deepwater 

Horizon’ and the resulting sub-sea well blowout and recovery operations of the 

exploration well at the MC-252 ‘Macondo’ location. 

3) Information Requirements. 

a) Blowout scenario. 

The exploration well is drilled to the objective sands as outlined in the Geological and 

Geophysical Information Section of this Plan utilizing a typical sub-sea wellhead 

system, conductor, surface and intermediate casing program, and using a MODU rig 

with a marine riser and sub-sea BOP. A hydrocarbon influx and a well control event 

occurred from the objective sands during a trip out of the hole (ie drill pipe in the hole 

but not at the total depth of the well) followed by failure of the sub-sea BOP and 

marine riser and a blow-out to the seabed. 

b) Estimated flow rate of the potential blowout. 

Category Revised EP

Type of Activity Exploratory Drilling

Facility Location (area/block) WR 325 Well Location “B”

Facility Designation MODU

Distance to Nearest Shoreline (miles) 165

Uncontrolled blowout (volume per day) 31,190 bbls

Type of Fluid(s) Crude 

c) Total volume and maximum duration of the potential blowout. 

Category Initial EP

Duration of flow (days) 21 days to contract/mob rig 

159 days to drill relief well

180 days total duration 

Total volume of spill (bbls) 5,614,200 
d) Potential for the well to bridge over. 

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

several factors including in-situ stress, rock strength and fluid velocities at the 

sandface. Given the fluid velocities inherent in a blowout, it is possible that the 

borehole may fail/collapse/bridge over within the span of a week. 

e) Likelihood and measures taken for intervention to stop the blowout. 

 

The likelihood of surface intervention to stop a blowout is high and is based on the 

following equipment specific to the MODU - Maersk Developer that has been 

contracted to do this drilling program: 

• Acoustic Secondary BOP Control System: The rig has a Kongsberg acoustic BOP 

control system fitted to the BOP. This system has the ability to communicate with the 

BOP from surface in the event of failure of the primary umbilical control system from 

the rig under a scenario such as a loss of the rig or marine riser. Control can be 

established either from the surface acoustic package on the rig or by deploying a 

second acoustic control package on the back of a supply boat. The system is 

configured to provide control over the following functions: Blind / shear ram close - 

Pipe ram close - LMRP disconnect 

• ROV Secondary BOP Control System: The rig has two secondary ROV interface 

BOP control panels, one located on the lower BOP and a second located on the 

LMRP. This system is designed for an ROV hot stab to interface with the control 

panel and operate a specific function by direct hydraulic supply from the ROV. 

The system is configured to provide control over the following functions: - Blind / 

shear ram open and close - Casing (super) shear ram open and close - Auto shear 

sequence - Pipe rams open and close - LMRP disconnect - Wellhead disconnect The 

rig is equipped with two ROV’s which provides additional redundancy. The panels 

could also be operated by an ROV from independent supply boat in the event of a loss 

of rig scenario. The ROV panel has been tested using the rig based ROV with the 

BOP on a wellhead on the seabed and the actual hot stab. A close of the blind shear 

rams was successfully achieved in 13 minutes using the ROV’s direct hydraulic 

supply. 

• Deadman / autoshear function: The rig is equipped 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. These systems were satisfactorily tested during rig 

commissioning and periodically during pre-drill operations. 

f) Availability of a rig to drill a relief well.

Woodside currently has one deepwater MODU (Maersk Developer) on contract and 

located in the US GOM for exploration drilling. If the blowout scenario does not 

involve the loss or damage of the rig (eg: marine riser failure only), then the existing 
contracted rig may be available for drilling the relief well. Maersk Drilling owns and 

maintains spare riser joints and a spare BOP in the US GOM.

If the blowout scenario involves significant damage or total loss of this rig then a 

replacement rig will be required to be contracted.

The US GOM activity level currently supports a deepwater operating fleet of between 

25 to 40 MODU’s with the majority of those rigs being dynamically positioned 

vessels. The GOM is considered a mature operating environment with a significant 

local rig fleet capable of conducting relief well operations. The ability to negotiate 

and contract a rig of similar capability under the scenario of a requirement to drill a 

relief well is considered high.

Woodside has also established and signed mutual aid agreements both with the Helix 

Well Containment Group (HWCG) and with the Global Rig Share Solutions Group 

(GRSS) to provide the framework and guiding principles for gaining access to another 

members rig or providing Woodside’s own contracted rig to another member operator 

in need of a rig to respond to a blowout scenario. 

Contracting strategy: 

• Request rig availability from existing strategic partners and mutual aid agreement 

partners in the US GOM.

• Request rig availability from the wider GOM fleet through direct contact and 

negotiation and by utilizing the established communication network between the US 

GOM operator drilling organizations. 

g) Rig constraints. 

The US GOM deepwater rig fleet consists of mainly 4th to 6th generation 

dynamically positioned MODU’s which are capable of performing equivalent relief 

well operations at the Ivan location. The smaller US GOM fleet of anchored 

MODU’s that can work in deepwater would have time and equipment constraints of 

mobilizing and setting up a deepwater anchoring spread at the location and would not 

be the preferred option for the drilling of a relief well. 

h) Time taken to contract a rig, move it onsite and drill a relief well. 

 

Between 2008 and 2010 the US GOM rig fleet has typically been close to 95% 

utilization on deepwater exploration and development projects for multiple US GOM 

operators. This high utilization means that any rig that is contracted for a relief well 

will likely have to suspend current operations on an existing well before moving to 

prepare for drilling a relief well. It is estimated that 14 days is typically required to 

suspend a well and pull the BOP and be ready to move to a new location. It is 

estimated a further 7 days is then required to mobilize and be ready to spud at the 

relief well location. 

i) Assumptions and calculations used in determining the worst case discharge as well 

as directional survey and wellbore schematic are listed in Appendix A (proprietary 

information). 
k) Measures taken to enhance ability to prevent a blowout. 

• Well design: Woodside uses a systematic well design process for the planning and 

construction of a well operation. This process involves an assurance plan covering 

each step of the well design and an independent peer review of the well design and of 

the shallow hazards and formation pressure hazards expected during drilling. These 

are the critical design steps required to minimize the potential for an unplanned well 

control event that could lead to a blowout. This process will also include a 

Professional Engineer review and approval of the final casing design. 

Woodside’s drilling philosophy is to provide a detailed pre-drill assessment of 

formation pressure and provide 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 and 

minimize the risk of an unplanned well control event. 

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 provide assurance that 

the rig can successfully mitigate a loss of well control event and prevent it from 

becoming a blowout scenario. 

 

• Barrier Philosophy: For the exploration well design Woodside will require and use 

two independent barriers for both internal and external flow paths and conduct 

positive and negative testing to confirm integrity of those barriers in accordance with 

NTL No. 2010-N05. 

 

• Management of change protocol: Woodside uses a ‘Management of Change’ 

system for monitoring and approving changes in the well design or well construction 

that require a deviation from the approved Drilling Program. Where an unplanned 

result in the offshore operation requires a change or deviation from the approved 

drilling plan, a risk based decision with formal onshore management approval is 

required before continuing the operation. 

 

• BOP and well control equipment: The Maersk Developer has a 15k psi (6 ram / 2 

annular) Hydril BOP with primary and secondary BOP control systems. The BOP 

was delivered new in 2008. The BOP and well control equipment was audited during 

the rig construction and commissioning process by an independent third party. Prior 

to commencement of operations at the location, a BOP certification package will be 

submitted as part of the APD process that details the compliance with the Original 

Equipment Manufacturer (OEM) and applicable federal regulations including NTL 

No. 2010-N05. 

• Gas Handler: The Maersk Developer has an operational gas handler marine riser 

joint which is normally installed near the top of the marine riser below the moon pool. 

The purpose of the gas handler is to provide another means for closing an annular 

element near surface and capturing any gas that has found its way above the BOP and 

into the marine riser. The gas handler has the means to circulate this gas from under 
the closed annular in a controlled manner and back through conventional surface well 

control equipment. This item of well control equipment is relatively unique in the 

industry and has a direct application for deepwater operations. 

• 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 at the GC-451 well. This testing program will 

provide compliance with current federal regulations for pressure and function testing 

and will also provide periodic assurance on the performance of both primary and 

secondary BOP control systems including actual interface operations with the ROV 

and the ROV panel.

• Well control training and drills. Woodside’s Well Control Manual requires that key 

nominated onshore and offshore positions including rig contractor personnel hold an 

IWCF, WELLCAP or equivalent well control training certificate, renewable every 

two years for the type of floating drilling operation being conducted. Woodside also 

monitors compliance for its personnel with the federal regulations and Sub-Part O for 

well control training. A comprehensive program of well control drills will be 

conducted offshore to ensure readiness to identify and then manage a well control 

situation and thereby minimize the potential for a well control event to lead to a 

blowout scenario. 

l) Arrangements for drilling a relief well 

Woodside maintains a master agreement with ‘Wild Well Control’ for advice, 

management, engineering, well kick pre and post modelling and resource support for 

an unplanned loss of well control event. In the event of any well control event, Wild 

Well Control would be contacted and mobilized if required to support Woodside’s 

operational team both in the onshore and offshore locations. During a significant 

loss of well control event, Woodside would mobilize up from a standard drilling 

support organization in Houston, Texas to a 24 hr / 7 days a week onshore capability 

utilizing both local operations resources within the Woodside USA organization and 

the wider Woodside Energy organization in Australia. A conceptual relief well 

design will be prepared ahead of time and issued with the Application to Drill. This 

conceptual well design would be finalized based on the exact circumstance of the loss 

of well control event. 

Back-up long lead equipment equivalent to the original well design will be carried in 

stock to allow a rapid response. This includes a spare deepwater sub-sea wellhead 

system and the large OD casing (36”, 28” 22”, 18” and 16”) and the connectors 

required for the first part of the well. Smaller OD casing is considered widely 

available on the ground in the GOM and would be resourced out of existing inventory 

or from suppliers as required. 

Existing service agreements will be in place for support services including drilling 

fluids, casing running, cementing, ROV’s, solids control, mud logging, directional 

drilling, LWD/MWD, logging, boats and helicopters.

 

Specialist services for range finding to drill the relief well in close proximity to the 

original wellbore at the reservoir depth will be provided through Vector Magnetics 
LLC as a sub-contractor to Baker Hughes Inteq under our existing directional drilling 

agreement. 

The WR-325 block has three well locations identified and cleared for shallow hazards 

as part of Exploration Plan N-9414. A fourth location in this block has been 

identified and cleared for shallow hazards and will be submitted as a Supplemental 

EP. Depending on the nature of the blowout scenario and the total depth required to 

intersect the blowout zone, these previously cleared areas would be reviewed for best 

suitability for the location of the relief well. After selecting the most suitable surface 

location a directional plan would be prepared and issued within a 48 hour period. 

There are no adjacent platforms which could be used to drill the relief well.

m) Mutual aid support and the Well Containment Plan. 

Woodside has entered into a membership agreement with the Helix Well Containment 

Group (HWCG). The HWCG is a consortium of deepwater operators in the Gulf of 

Mexico that has joined together to form a collective response capability for the 

management of a subsea well control incident and/or blowout. This membership 

provides access for the member companies to each others assets, people and 

equipment via a mutual aid agreement. It is anticipated that a response organization 

would be progressively established during an emergency using resources from the 

HWCG membership group and from Woodside in Australia to support the existing 

Woodside USA operations capability based in Houston, Texas, USA. Woodside’s 

response plan for a subsea blowout will be documented in a Well Containment Plan 

(WCP) specific for each well and submitted as required with the Application to Drill.

Woodside, through membership of the Clean Gulf Association (CGA) has entered 

into a contract with the Helix Energy Solutions Group for use of the Helix Fast 

Response System (HFRS) which provides the core equipment and services required to 

support the WCP. Woodside has also established separate master service agreements 

with a range of service providers who would also provide equipment, people and 

services to support the WCP.
 

 

Appendix D 

Interpreted 2-D or 3-D Seismic Lines 

Geological Structure Cross-Sections 

High Resolution Seismic Lines 

Stratigraphic Column 

Time vs. Depth Tables 
 

 

Appendix E 

Shallow Hazard and Archaeological Assessments

(Submitted Previously)

High Resolution Seismic Lines

 (See Appendix D) 
10615 SHADOW WOOD DRIVE

SUITE 200

HOUSTON, TEXAS 77043

Phone: (713) 468-1410 

Fax: (713) 468-1438

E-mail: gems@gemsinc.com

February 17, 2011 Project No.0211-1878

Woodside Energy (USA) Inc. 

830 Causeway Approach, Suite 1000 

Mandeville, LA 70471 

Attention: Mr. Douglas Lumpkin 

Site Clearance Letter 

Proposed Wellsite A

Block 325 (OCS-G-32673) 

Walker Ridge Area

Gulf of Mexico

Woodside Energy (USA) Inc., (Woodside) proposes an exploration wellsite in Walker Ridge Block 325. 

The Proposed Wellsite A location in Walker Ridge area, Block 325 appears favorable for exploration 

drilling operations relevant to the shallow geologic and stratigraphic conditions. The original geohazard 

report (GEMS, 0608-1503) and this letter comply with the Bureau of Ocean Energy Management, 

Regulation, and Enforcement (BOEMRE) Notice-to-Lessees (NTL’s), 2008-G04, 2008-G05, and 2009-

G40 (MMS, 2008a,b, and 2009b).

Walker Ridge (WR) Block 325 is not in an area of archaeological potential. Therefore, the NTL's 2005-

G07 and 2008-G20 do not apply (MMS, 2005, 2008d). Likewise WR 325 is not in a Military Warning 

area; therefore, requirements in NTL-2009-G06 are not applicable (MMS, 2009a). 

Introduction

Woodside Energy (USA) Inc., (Woodside) contracted Geoscience Earth & Marine Services, Inc.

®, 

(GEMS) to prepare a geohazard analysis of Block 325 of the Walker Ridge (WR) Area, Gulf of Mexico. 

The geohazard report discusses the seafloor and subsurface conditions within WR 325 and surrounding 

blocks based on 3-D geophysical data. 

Woodside has designated several possible drilling locations within the study area. This Site Clearance 

Letter addresses the specific conditions at Proposed Wellsite WR 325-A (OCS-G-32673). This proposed 

location is plotted on the maps referenced in the main text of this report and is the subject of individual 

plat maps included with this letter. The seismic figures included with this letter are taken from the 3-D 

data volume used for the geohazard assessment of the study area. 

The Proposed Wellsite WR 325-A surface location is located in the southeastern corner of Block 325, 

Walker Ridge area, Gulf of Mexico. Woodside provided the following coordinates: 

Proposed Wellsite WR 325-A

Spheroid & Datum: Clarke 1866, NAD27

Projection: UTM Zone 15 North Block Calls Inline/Crossline

X: 2,263,918 ft Latitude: 26.619594139o N 1,479 ft FSL IN 10951

Y: 9,663,879 ft Longitude: 91.091161036o W 1,202 ft FEL XL 12045
Project No. 0211-1878

 - 2 - Proposed Well WR 325-A 

Attachments

The figures accompanying this letter were extracted from the 3-D data volume. The figures (listed below) 

are centered on the proposed well location. 

Figure A-1: Tophole Prognosis Chart, Proposed Wellsite A, Walker Ridge Block 325 

Figure A-2: Inline 10951 and Crossline 12045 Showing Conditions Beneath Proposed Wellsite A, 

Walker Ridge Block 325

Figure A-3: Power Spectrum Chart Based on 3-D Data Volume Within 500-ft Radius of Proposed 

Wellsite A, Walker Ridge Block 325. 

The page-sized plat maps are taken from the full-scale (1:12,000) maps included in the report. The plat 

maps are centered on the Proposed Wellsite WR 325-A. The maps included in this letter are as follows:

Map A-1: Bathymetry Map, Proposed Wellsite A, Walker Ridge Block 325 

Map A-2: Enhanced Seafloor Rendering, Wellsite A, Walker Ridge Block 325 

Map A-3: Amplitude-Enhanced Seafloor Rendering Wellsite A, Walker Ridge Block 325

Map A-4 Geologic Features Map, Wellsite A, Walker Ridge Block 325 

Water Depth and Seafloor Conditions

The water depth at the proposed location is -6,343 ft (Map A-1 and Figure A-1). The seafloor slopes to the 

east at a gradient of 1.1° (1.9%). 

WR 325-A is situated above a shallow salt sheet. The overburden above the top of salt is approximately 

1,528 ft thick (Figures A-1 and A-2). The seafloor topography mimics the folded and faulted salt surface. 

Several faults affect the seafloor east of the proposed location (Figure A-2 and Maps A-1 through A-4). 

The closest offset is approximately 120 ft to the east. The possible fault is downthrown away from the 

proposed location, and therefore, will not cross the wellbore. The slope along the fault “scarp” is 3° to 7°. 

Deepwater Benthic Communities

There is no evidence of hydrocarbon seepage within 2,000 ft of the proposed location. Therefore, the 

potential for high-density chemosynthetic or other deepwater benthic communities within 2,000 ft of the 

proposed location is negligible. The Amplitude-Enhanced Surface Rendering (Map A-3) shows normal or 

ambient amplitudes along the seabed near the proposed wellsite. 

The Enhanced Surface Rendering and Amplitude-Enhanced Surface Rendering show few indications of 

seepage-related features within the area examined for this evaluation. A cluster of small mud mounds 

occur in the southwest corner of WR 325 (GEMS report, Maps 2 through 4). The small mounds may be 

seepage related and therefore have the potential for supporting chemosynthetic communities. However, the 

closest feature is approximately 11,000 ft from the proposed location. These mounds will not be affected 

by the planned dynamically positioned drill rig at the Proposed Wellsite WR 325-A. 

Man-Made Features

No wells or oilfield infrastructure occur within WR 325. In addition, no shipwrecks or other man-made 

debris are reported in the vicinity. The nearest exploration well is in WR 371 approximately 6 miles to the 

southeast of the Proposed Wellsite WR 325-A. 

Stratigraphy 

Inline 10951 and Crossline 12045 are the closest lines to the Proposed Wellsite WR 325-A (Figure A-2). 

The Tophole Prognosis Chart (Figure A-1) shows the crossline annotated with calculated depths to the 

various horizons and predicted lithology of the sequences, along with their potential for shallow water flow 

and shallow gas. 
Project No. 0211-1878

 - 3 - Proposed Well WR 325-A 

The top of salt is estimated to be approximately 1,528 ft below the mudline (bml) at this location. The 

relatively thin overburden is divided into five units or sequences. The sequences represent variations in 

depositional environments and possible changes in soil strength and composition. 

The surficial unit, Unit 1 (Seafloor to Horizon A), to approximately 137 ft bml, will consist of mud-rich 

hemipelagic and thin mass-transport deposits. The soils at the seabed are likely to be soft high water 

content silty clays. The shear strength of the sediments will increase with depth corresponding to a 

decrease in water content. Stiff, overconsolidated sediments have been encountered in some areas along 

the lower continental slope above shallow salt sheets. Some of these areas generally have experienced 

erosion from strong bottom currents. No evidence of furrows or other erosional seabed features are 

identified around the proposed wellsite. However, overconsolidated sediments have occurred near the 

seafloor because of uplift and erosion of the section caused by the emplacement of the salt mass. Scout 

tickets indicate the surface casing in the offset well WR 285-1 was set at ~251 ft while the surface casing 

for the WR 372-1 well was 324 ft. It is not known whether the difference in casing depths were the result 

of variable soil conditions or the engineering parameters of the different rigs and drilling programs. 

The base of the surficial sequence (Unit 1) is Horizon 10 which is a continuous prominent reflecting 

horizon mapped throughout the study area (Figure A-1 and A-2). Units 2 and 3, between Horizons 10 and 

20 and Horizons 20 and 30 respectively, generally consist of relatively continuous stratified reflections. 

These units will also be mud-rich and consist of hemipelagic, turbidite, and mass-transport deposits. 

Slightly higher amplitudes in Unit 3 suggest the presence of thin sand seams.

Unit 4, between Horizons 30 and 40, generally consists of low-amplitude, discontinuous to chaotic 

reflections. This is predominantly a mud-rich, mass-transport complex. Occasional sand pockets or seams 

are possible within this unit but are not likely beneath proposed location WR 325-A. 

Unit 5 occurs between Horizon 40 and the top of salt (Figures A-1 and A-2). Reflections within this 

sequence are layered and are of moderate amplitude. Reflection continuity varies from parallel and 

continuous to discontinuous to chaotic. The deterioration in continuity reflects distortion of the section by 

faulting and folding of the unit above the shallow salt sheet and not a change in depositional environment. 

Unit 5 probably consists of turbidites interlayered with thin mass-transport deposits. The sequence may 

have been part of a slope-fan complex. The turbidites will consist of alternating layers of clay, silt, and 

sand. The relatively high-amplitude of the reflections in general and the distribution of bright spots within 

the sequence suggest that thin sand layers are possible. The unit is highly fractured by faulting, indicating 

that high pore water pressures are not likely to be encountered. No high-amplitude events occur beneath 

the proposed location within this unit. 

The top of salt at Proposed Wellsite WR 325-A is at -7,871 ft subsea (1,528 ft bml). The salt surface dips 

to the southwest at approximately 9.0°. 

Faults

Several seafloor faults occur to the east of Proposed Wellsite WR 325-A (Map A-4). The closest fault is 

120 ft to the east. The fault is downthrown away from the wellsite. The “scarp” created by this fault only 

amounts to an increase in seafloor slope of 3° to 7° which is a gentle flexure of the seabed. The fault is 

probably inactive and covered by a Holocene-aged pelagic drape. 

At depth the wellbore will intersect two fault planes at 767 ft bml and 1,229 ft bml (Figures A-1 and A-2). 

These faults do not extend to the seafloor and are buried by approximately 700 ft of sediment. Therefore, 

these faults have been inactive for a considerable amount of time. No shallow gas anomalies are associated 

with these fault planes; however, engineers should be aware that, on occasion, fault planes can be zones of 

lost circulation. The shallow fault (767 ft bml) will be encountered in Unit 4 which is a mud-rich masstransport sequence. The deeper fault at 1,229 ft bml will be crossed in the turbidites of Unit 5. Thin sands 

are possible in the turbidites. 
Project No. 0211-1878

 - 4 - Proposed Well WR 325-A 

Shallow Water Flow

The sedimentary section above the salt surface is 1,528 ft thick. Unit 5, between 1,093 ft to 1,528 ft bml, is 

a turbidite sequence possibly containing thin sand layers. However, the unit is highly faulted and fractured 

and possibly experienced erosion caused by uplift during emplacement of the salt sheet. High pore water 

pressures existing within this unit after deposition has likely dissipated during the period of active salt 

tectonics. 

In general, shallow water flow incidents have not been reported in the Walker Ridge area (BOEMRE, 

2011). 

Shallow Gas 

The well path will not penetrate any high-amplitude events between the seafloor and top of salt (Figures A1 and A-2). The potential for shallow gas accumulations beneath Proposed Wellsite WR 325-A is minimal. 

Power Spectrum 

In accordance with NTL 2008-G04 and NTL 2008-G05 (MMS 2008a,b), we have extracted the power 

spectrum diagram (Figure A-3) from the 3-D seismic data cube. The extraction was generated within a 

500-ft radius of the intersection of the inlines and crosslines at the proposed wellsite. We converted the 

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

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

Figure A-3 Power Spectrum Chart Based on 3-D Data Volume Within 500-ft Radius of Proposed Wellsite A, Walker Ridge Block 325.
Project No. 0211-1878

 - 5 - Proposed Well WR 325-A 

Closing

The seafloor at Proposed Wellsite WR 325-A, Walker Ridge Block 325 (OCS-G-32673), appears suitable 

for exploration drilling operations. No major hazards or constraints are defined by the 3-D data at the 

proposed location. 

We appreciate the opportunity to be of service to Woodside Energy (USA) Inc., and look forward to 

working closely with you on other projects. 

Sincerely,

GEOSCIENCE EARTH & MARINE

SERVICES, INC.®

Thomas W. Neurauter Ph. D. Daniel Lanier 

Senior Marine Geologist Vice-President/Marine Geologist

Attachments (3 Figures, 4 Maps)

Distribution:

Mr. Douglas Lumpkin Mandeville, LA (3) 

References:

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

Bureau of Ocean Energy Management, Regulation, and Enforcement, 2011, ASCII Data Files, published on the BOEMRE Gulf of Mexico Region 

Homepage, <http://www.gomr.boemre.gov/homepg/pubinfo/freeasci/freedesc.html>, Accessed February, 2011.

Minerals Management Service, 2005, Notice to lessees and operators of federal oil, gas, and sulphur leases and pipeline right-of-way holders in the 

outer continental shelf, Gulf of Mexico OCS region; archaeological resource surveys and reports, U. S. Department of the Interior, Minerals 

Management Service, Gulf of Mexico, NTL 2005-G07. Effective Date July 1, 2005.

Minerals Management Service, 2008a, Notice to lessees and operators of federal oil, gas, and sulfur leases and pipeline right-of-way holders in the 

outer continental shelf, Gulf of Mexico OCS region; information requirements for Exploration Plans and Development Operations Coordination 

Documents, U. S. Department of the Interior, Minerals Management Service, Gulf of Mexico, NTL 2008-G04. Effective Date May 01, 2008.

Minerals Management Service, 2008b, Notice to lessees and operators of federal oil, gas, and sulfur leases and pipeline right-of-way holders in the 

outer continental shelf, Gulf of Mexico OCS region; shallow hazards program, U. S. Department of the Interior, Minerals Management Service, 

Gulf of Mexico, NTL 2008-G05. Effective Date May 01, 2008.

Minerals Management Service, 2008c, Notice to lessees and operators of federal oil, gas, and sulphur leases in the outer continental shelf, Gulf of 

Mexico OCS region; remotely operated vehicle surveys in deepwater, U. S. Department of the Interior, Minerals Management Service, Gulf of 

Mexico, NTL 2008-G06. Effective Date May 26, 2008.

Minerals Management Service, 2008d, Notice to lessees and operators of federal oil and gas leases and pipeline right-of-way holders on the outer 

continental shelf, Gulf of Mexico OCS region, Revisions to the list of OCS lease blocks requiring archaeological resource surveys and reports: U. 

S. Department of the Interior, Minerals Management Service, Gulf of Mexico, NTL 2008-G20. Effective Date October 20, 2008.

Minerals Management Service, 2009a, Notice to lessees and operators of federal oil and gas leases and pipeline right-of-way holders on the outer 

continental shelf, Gulf of Mexico OCS region, Military Warning and Water Test Areas: U. S. Department of the Interior, Minerals Management 

Service, Gulf of Mexico, NTL 2009-G06. Effective Date April 22, 2009.

Minerals Management Service, 2009b, Notice to lessees and operators of federal oil and gas leases in the outer continental shelf, Gulf of Mexico 

OCS region, deepwater benthic communities: U. S. Department of the Interior, Minerals Management Service, Gulf of Mexico, NTL 2009-G40. 

Effective Date: January 27, 2010.
10615 SHADOW WOOD DRIVE

SUITE 200

HOUSTON, TEXAS 77043

Phone: (713) 468-1410 

Fax: (713) 468-1438

E-mail: gems@gemsinc.com

February 17, 2011 Project No. 0211-1878

Woodside Energy (USA), Inc., 

830 Causeway Approach, Suite 1000 

Mandeville, LA 70471 

Attention: Mr. Douglas Lumpkin 

Site Clearance Letter 

Proposed Wellsite B 

Block 325 (OCS-G-32673) 

Walker Ridge Area

Gulf of Mexico

Woodside Energy (USA) Inc., (Woodside) proposes an exploration wellsite in Walker Ridge Block 325. 

The Proposed Wellsite B location in Walker Ridge area, Block 325 appears favorable for exploration 

drilling operations relevant to the shallow geologic and stratigraphic conditions. The original geohazard 

report (GEMS, 0608-1503) and this letter comply with the Bureau of Ocean Energy Management, 

Regulation, and Enforcement (BOEMRE) Notice-to-Lessees (NTL’s), 2008-G04, 2008-G05, and 2009-

G40 (MMS, 2008a,b, and 2009b).

Walker Ridge (WR) Block 325 is not in an area of archaeological potential. Therefore, the NTL's 2005-

G07 and 2008-G20 do not apply (MMS, 2005, 2008d). Likewise WR 325 is not in a Military Warning 

area; therefore, requirements in NTL-2009-G06 are not applicable (MMS, 2009a). 

Introduction

Woodside Energy (USA) Inc., (Woodside) contracted Geoscience Earth & Marine Services, Inc.

®, 

(GEMS) to prepare a geohazard analysis of Block 325 of the Walker Ridge (WR) Area, Gulf of Mexico. 

The geohazard report discusses the seafloor and subsurface conditions within WR 325 and surrounding 

blocks based on 3-D geophysical data. 

Woodside has designated several possible drilling locations within the study area. This Site Clearance 

Letter addresses the specific conditions at Proposed Wellsite WR 325-B (OCS-G-32673). This proposed 

location is plotted on the maps referenced in the main text of this report and in the plat maps included with 

this letter. The seismic figures included with this letter are taken from the 3-D data volume used for the 

geohazard assessment of the study area. 

The Proposed Wellsite WR 325-B surface location is located in the southeastern corner of Block 325, 

Walker Ridge area, Gulf of Mexico. Woodside provided the following coordinates: 

Proposed Wellsite WR 325-B

Spheroid & Datum: Clarke 1866, NAD27

Projection: UTM Zone 15 North Block Calls Inline/Crossline

X: 2,263,211 ft Latitude: 26.621567874o N 2,186 ft FSL IN 10956

Y: 9,664,586 ft Longitude: 91.093292269o W 1,909 ft FEL XL 12068
Project No. 0211-1878

 - 2 - Proposed Well WR 325-B 

Attachments

The figures accompanying this letter were extracted from the 3-D data volume. The figures (listed below) 

are centered on the proposed well location. 

Figure B-1: Tophole Prognosis Chart, Proposed Wellsite B, Walker Ridge Block 325 

Figure B-2: Inline 10956 and Crossline 12068 Showing Conditions Beneath Proposed Wellsite B, 

Walker Ridge Block 325

Figure B-3: Power Spectrum Chart Based on 3-D Data Volume Within 500-ft Radius of Proposed 

Wellsite B, Walker Ridge Block 325. 

The page-sized plat maps are taken from the full-scale (1:12,000) maps included in the report. The plat 

maps are centered on the proposed WR 325-B location. The maps included in this letter are as follows:

Map B-1: Bathymetry Map, Proposed Wellsite B, Walker Ridge Block 325 

Map B-2: Enhanced Seafloor Rendering, Wellsite B, Walker Ridge Block 325 

Map B-3: Amplitude-Enhanced Seafloor Rendering Wellsite B, Walker Ridge Block 325

Map B-4 Geologic Features Map, Wellsite B, Walker Ridge Block 325 

Water Depth and Seafloor Conditions

The water depth at the proposed location is -6,334 ft (Map B-1 and Figure B-1). The seafloor slopes to the 

southeast at a gradient of 0.7° (1.2%). 

Proposed Wellsite WR 325-B is situated above a shallow salt sheet. The overburden above the top of salt 

is approximately 1,650 ft thick (Figures B-1 and B-2). The seafloor topography mimics the folded and 

faulted salt surface. Several faults affect the seafloor east of the proposed location (Figure B-2 and Maps 

B-1 through B-4). The closest offset is approximately 565 ft to the southeast. The second closest fault is 

approximately 900 ft to the northeast. The seafloor faults are all downthrown away from the proposed 

location, and therefore, will not cross the wellbore. The seafloor along the fault “scarps” range in gradients 

from 2° to 7°.

Deepwater Benthic Communities 

There is no evidence of hydrocarbon seepage within 2,000 ft of the proposed location. Therefore, the 

potential for high-density chemosynthetic or other benthic communities within 2,000 ft of the proposed 

location is negligible. The Amplitude-Enhanced Surface Rendering (Map B-3) shows normal or ambient 

amplitudes along the seabed near the proposed wellsite. 

The Enhanced Surface Rendering and Amplitude-Enhanced Surface Rendering show few indications of 

seepage-related features within the area examined for this evaluation. A cluster of small mud mounds 

occur in the southwest corner of WR 325 (GEMS report Maps 2 through 4). The small mounds may be 

seepage related and therefore have the potential for supporting chemosynthetic communities. However, the 

closest feature is approximately 10,500 ft from Proposed Wellsite WR 325-B. These mounds will not be 

affected by the planned dynamically positioned drill rig at the proposed B location. 

Man-Made Features

No wells or oilfield infrastructure occur within WR 325. In addition, no shipwrecks or other man-made 

debris are reported in the vicinity. The surface location of the nearest exploration well is in WR 371 

approximately 6 miles to the southeast of Proposed Wellsite WR 325-B. 

Stratigraphy 

Inline 10956 and Crossline 12068 are the closest lines to Proposed Wellsite WR 325-B (Figure B-2). The 

Tophole Prognosis Chart (Figure B-1) shows the crossline annotated with calculated depths to the various 

horizons and predicted lithology of the sequences, along with their potential for shallow water flow and 

shallow gas. 
Project No. 0211-1878

 - 3 - Proposed Well WR 325-B 

The top of salt is estimated to be approximately 1,650 ft below the mudline (bml) at this location. The 

relatively thin overburden is divided into five units or sequences. The sequences represent variations in 

depositional environments and possible changes in soil strength and composition. 

The surficial unit, Unit 1 (Seafloor to Horizon A), to approximately 138 ft bml, will consist of mud-rich 

hemipelagic and thin mass-transport deposits. The soils at the seabed are likely to be soft high water 

content silty clays. The shear strength of the sediments will increase with depth corresponding to a 

decrease in water content. Stiff, overconsolidated sediments have been encountered in some areas along 

the lower continental slope above shallow salt sheets. Some of these areas generally have experienced 

erosion from strong bottom currents. No evidence of furrows or other erosional seabed features are 

identified around the proposed wellsite. However, overconsolidated sediments have occurred near the 

seafloor because of uplift and erosion of the section caused by the emplacement of the salt mass. Scout 

tickets indicate the surface casing in the offset well, WR 285-1, was set at ~251 ft while the surface casing 

at WR 372-1 was 324 ft. It is not known whether the difference in casing depths were the result of variable

soil conditions or the engineering parameters of the different rigs and drilling programs. 

The base of the surficial sequence (Unit 1) is Horizon 10 which is a continuous prominent reflecting 

horizon mapped throughout the study area (Figure B-1 and B-2). Units 2 and 3, between Horizons 10 and 

20 and Horizons 20 and 30 respectively, generally consist of relatively continuous stratified reflections. 

These units will also be mud-rich and consist of hemipelagic, turbidite, and mass-transport deposits. 

Slightly higher amplitudes in Unit 3 suggest the presence of thin sand seams.

Unit 4, between Horizons 30 and 40, generally consists of low-amplitude, discontinuous to chaotic 

reflections. This is predominantly a mud-rich, mass-transport complex. Occasional sand pockets or seams 

are possible within this unit but are not likely beneath Proposed Wellsite WR 325-B. 

Unit 5 occurs between Horizon 40 and the top of salt (Figures B-1 and B-2). Reflections within this 

sequence are layered and are of moderate amplitude. Reflection continuity varies from parallel and 

continuous to discontinuous to chaotic. The deterioration in continuity reflects distortion of the section by 

faulting and folding of the unit above the shallow salt sheet and not a change in depositional environment. 

Unit 5 probably consists of turbidites interlayered with thin mass-transport deposits. The sequence may 

have been part of a slope-fan complex. The turbidites will consist of alternating layers of clay, silt, and 

sand. The relatively high-amplitude of the reflections in general and the distribution of bright spots within 

the sequence suggest that thin sand layers are possible. The unit is highly fractured by faulting, indicating 

that high pore water pressures are not likely to be encountered. No high-amplitude events occur beneath 

the proposed location within this unit. 

The top of salt at WR 325-B is at -7,984 ft subsea (1,650 ft bml). A northwest-southeast trending 

escarpment occurs along the salt surface beneath Proposed Wellsite WR 325-B. The salt surface along this 

escarpment dips to the southwest at approximately 30°.

Faults

Several seafloor faults occur to the east of Proposed Wellsite WR 325-B (Map B-4). The closest fault is 

565 ft to the southeast. The fault is downthrown away from the wellsite. The “scarp” created by this fault 

only amounts to an increase in seafloor slope of 3° to 7° which is a gentle flexure of the seabed. The fault 

is probably inactive and covered by a Holocene-aged pelagic drape. 

The wellbore will intersect one fault plane at ~468 ft bml (Figures B-1 and B-2). The fault intersection will 

be near the top of Unit 3, a mixture of hemipelagic and mud-rich turbidite deposits. The fault does not 

extend to the seafloor and is buried by approximately 400 ft of sediment. Therefore, this fault has been 

inactive for a considerable amount of time. No shallow gas anomalies are associated with this fault plane; 

however, engineers should be aware that, on occasion, fault planes can be zones of lost circulation. 
Project No. 0211-1878

 - 4 - Proposed Well WR 325-B 

The steep escarpment along the top of salt may be a fault plane. Offsets in the sedimentary section 

immediately above the top of salt are not apparent. This is not an active fault; however, it does create a 

steep surface.

Shallow Water Flow

The sedimentary section above the salt surface is 1,650 ft thick. Unit 5, between 1,140 ft to 1,650 ft bml, is 

a turbidite sequence possibly containing thin sand layers. However, the unit is highly faulted and fractured 

and possibly experienced erosion caused by uplift during emplacement of the salt sheet. High pore water 

pressures existing within this unit after deposition has likely dissipated during the period of active salt 

tectonics. 

In general, shallow water flow incidents have not been reported in the Walker Ridge area (BOEMRE, 

2011). 

Shallow Gas 

The well path will not penetrate any high-amplitude events between the seafloor and top of salt (Figures B1 and B-2). The potential for shallow gas accumulations beneath Proposed Wellsite WR 325-B is minimal. 

Power Spectrum 

In accordance with NTL 2008-G04 and NTL 2008-G05 (MMS 2008a,b), we have extracted the power 

spectrum diagram (Figure B-3) from the 3-D seismic data cube. The extraction was generated within a 

500-ft radius of the intersection of the inlines and crosslines at the proposed wellsite. We converted the 

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

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

Figure B-3 Power Spectrum Chart Based on 3-D Data Volume Within 500-ft Radius of Proposed Wellsite B, Walker Ridge Block 325.
Project No. 0211-1878

 - 5 - Proposed Well WR 325-B 

Closing

The seafloor at Proposed Wellsite WR 325-B, Walker Ridge Block 325 (OCS-G-32673), appears suitable 

for exploration drilling operations. No major hazards or constraints are defined by the 3-D data at the 

proposed location. The well bore will encounter a salt surface dips with a relatively high gradient (~30o).

We appreciate the opportunity to be of service to Woodside Energy (USA) Inc., and look forward to 

working closely with you on other projects. 

Sincerely,

GEOSCIENCE EARTH & MARINE

SERVICES, INC.®

Thomas W. Neurauter Ph. D. Daniel Lanier

Senior Marine Geologist Vice-President/Marine Geologist

Attachments (3 Figures, 4 Maps)

Distribution:

Mr. Douglas Lumpkin Mandeville, LA (3) 

References:

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

Bureau of Ocean Energy Management, Regulation, and Enforcement, 2011, ASCII Data Files, published on the BOEMRE Gulf of Mexico Region 

Homepage, <http://www.gomr.boemre.gov/homepg/pubinfo/freeasci/freedesc.html>, Accessed February, 2011.

Minerals Management Service, 2005, Notice to lessees and operators of federal oil, gas, and sulphur leases and pipeline right-of-way holders in the 

outer continental shelf, Gulf of Mexico OCS region; archaeological resource surveys and reports, U. S. Department of the Interior, Minerals 

Management Service, Gulf of Mexico, NTL 2005-G07. Effective Date July 1, 2005.

Minerals Management Service, 2008a, Notice to lessees and operators of federal oil, gas, and sulfur leases and pipeline right-of-way holders in the 

outer continental shelf, Gulf of Mexico OCS region; information requirements for Exploration Plans and Development Operations Coordination 

Documents, U. S. Department of the Interior, Minerals Management Service, Gulf of Mexico, NTL 2008-G04. Effective Date May 01, 2008.

Minerals Management Service, 2008b, Notice to lessees and operators of federal oil, gas, and sulfur leases and pipeline right-of-way holders in the 

outer continental shelf, Gulf of Mexico OCS region; shallow hazards program, U. S. Department of the Interior, Minerals Management Service, 

Gulf of Mexico, NTL 2008-G05. Effective Date May 01, 2008.

Minerals Management Service, 2008c, Notice to lessees and operators of federal oil, gas, and sulphur leases in the outer continental shelf, Gulf of 

Mexico OCS region; remotely operated vehicle surveys in deepwater, U. S. Department of the Interior, Minerals Management Service, Gulf of 

Mexico, NTL 2008-G06. Effective Date May 26, 2008.

Minerals Management Service, 2008d, Notice to lessees and operators of federal oil and gas leases and pipeline right-of-way holders on the outer 

continental shelf, Gulf of Mexico OCS region, Revisions to the list of OCS lease blocks requiring archaeological resource surveys and reports: U. 

S. Department of the Interior, Minerals Management Service, Gulf of Mexico, NTL 2008-G20. Effective Date October 20, 2008.

Minerals Management Service, 2009a, Notice to lessees and operators of federal oil and gas leases and pipeline right-of-way holders on the outer 

continental shelf, Gulf of Mexico OCS region, Military Warning and Water Test Areas: U. S. Department of the Interior, Minerals Management 

Service, Gulf of Mexico, NTL 2009-G06. Effective Date April 22, 2009.

Minerals Management Service, 2009b, Notice to lessees and operators of federal oil and gas leases in the outer continental shelf, Gulf of Mexico 

OCS region, deepwater benthic communities: U. S. Department of the Interior, Minerals Management Service, Gulf of Mexico, NTL 2009-G40. 

Effective Date: January 27, 2010.
10615 SHADOW WOOD DRIVE

SUITE 200

HOUSTON, TEXAS 77043

Phone: (713) 468-1410 

Fax: (713) 468-1438

E-mail: gems@gemsinc.com

February 17, 2011 Project No.0211-1878

Woodside Energy (USA) Inc. 

830 Causeway Approach, Suite 1000 

Mandeville, LA 70471 

Attention: Mr. Douglas Lumpkin 

Site Clearance Letter 

Proposed Wellsite C 

Block 325 (OCS-G-32673) 

Walker Ridge Area

Gulf of Mexico

Woodside Energy (USA) Inc., (Woodside) proposes an exploration wellsite in Walker Ridge Block 325. 

The Proposed Wellsite WR 325-C location in Walker Ridge area, Block 325 appears favorable for 

exploration drilling operations relevant to the shallow geologic and stratigraphic conditions. The original 

geohazard report (GEMS, 0608-1503) and this letter comply with the Bureau of Ocean Energy 

Management, Regulation, and Enforcement (BOEMRE) Notice-to-Lessees (NTL’s), 2008-G04, 2008-G05, 

and 2009-G40 (MMS, 2008a,b, and 2009b).

Walker Ridge (WR) Block 325 is not in an area of archaeological potential. Therefore, the NTL's 2005-

G07 and 2008-G20 do not apply (MMS, 2005, 2008d). Likewise WR 325 is not in a Military Warning 

area; therefore, requirements in NTL-2009-G06 are not applicable (MMS, 2009a). 

Introduction

Woodside Energy (USA) Inc., (Woodside) contracted Geoscience Earth & Marine Services, Inc.

®, 

(GEMS) to prepare a geohazard analysis of Block 325 of the Walker Ridge (WR) Area, Gulf of Mexico. 

The geohazard report discusses the seafloor and subsurface conditions within WR 325 and surrounding 

blocks based on 3-D geophysical data. 

Woodside has designated several possible drilling locations within the study area. This Site Clearance 

Letter addresses the specific conditions at Proposed Wellsite WR 325-C (OCS-G-32673). This proposed 

location is plotted on the maps referenced in the main text of this report and is the subject of individual 

plat maps included with this letter. The seismic figures included with this letter are taken from the 3-D 

data volume used for the geohazard assessment of the study area. 

The Proposed Wellsite WR 325-C surface location is located in the southeastern corner of Block 325, 

Walker Ridge area, Gulf of Mexico. Woodside provided the following coordinates: 

Proposed Wellsite WR 325-C

Spheroid & Datum: Clarke 1866, NAD27

Projection: UTM Zone 15 North Block Calls Inline/Crossline

X: 2,264,177 ft Latitude: 26.622240624o N 2,445 ft FSL IN 10941

Y: 9,664,845 ft Longitude: 91.090324301o W 943 ft FEL XL 12064
Project No. 0211-1878

 2 Proposed Well WR 325-C 

Attachments

The figures accompanying this letter were extracted from the 3-D data volume. The figures (listed 

below) are centered on the proposed well location.

Figure C-1: Tophole Prognosis Chart, Proposed Wellsite C, Walker Ridge Block 325 

Figure C-2: Inline 10941 and Crossline 12064 Showing Conditions Beneath Proposed Wellsite C, 

Walker Ridge Block 325

Figure C-3: Power Spectrum Chart Based on 3-D Data Volume Within 500-ft Radius of Proposed 

Wellsite C, Walker Ridge Block 325.

The page-sized plat maps are taken from the full-scale (1:12,000) maps included in the report. The plat 

maps are centered on the proposed WR 325-C location. The maps included in this letter are as follows:

Map C-1: Bathymetry Map, Proposed Wellsite C, Walker Ridge Block 325 

Map C-2: Enhanced Seafloor Rendering, Wellsite C, Walker Ridge Block 325 

Map C-3: Amplitude-Enhanced Seafloor Rendering Wellsite C, Walker Ridge Block 325

Map C-4: Geologic Features Map, Wellsite C, Walker Ridge Block 325 

Water Depth and Seafloor Conditions

The water depth at the proposed location is -6,350 ft (Map C-1 and Figure C-1). The seafloor slopes to 

the north at a gradient of 1.5° (2.6%). 

Proposed Wellsite WR 325-C is situated above a shallow salt sheet. The overburden above the top of salt 

is approximately 1,448 ft thick (Figures C-1 and C-2). The seafloor topography mimics the folded and 

faulted salt surface. Several faults affect the seafloor east of the proposed location (Figure C-2 and Maps 

C-2 through C-4). The closest offset is approximately 250 ft to the east. The fault is downthrown away 

from the proposed location, and therefore, will not cross the wellbore. The slope along the fault “scarp” 

is 2° to 5°.

Deepwater Benthic Communities

There is no evidence of hydrocarbon seepage within 2,000 ft of the proposed location. Therefore, the 

potential for high-density chemosynthetic or other deepwater benthic communities within 2,000 ft of the 

proposed location is negligible. The Amplitude-Enhanced Surface Rendering (Map C-3) shows normal 

or ambient amplitudes along the seabed near the proposed wellsite. 

The Enhanced Surface Rendering and Amplitude-Enhanced Surface Rendering show few indications of 

seepage-related features within the area examined for this evaluation. A cluster of small mud mounds 

occur in the southwest corner of WR 325 (GEMS report Maps 2 and 3). The small mounds may be 

seepage related and therefore have the potential for supporting chemosynthetic communities. However, 

the closest feature is approximately 11,500 ft from the Proposed Wellsite WR 325-C. These mounds will 

not be affected by the planned dynamically positioned drill rig at Proposed Wellsite WR 325-C. 

Man-Made Features

No wells or oilfield infrastructure occur within WR 325. In addition, no shipwrecks or other man-made 

debris are reported in the vicinity. The surface location for the nearest exploration well is in WR 371, 

approximately 6 miles to the southeast of Proposed Wellsite WR 325-C. 

Stratigraphy 

Inline 10941 and Crossline 12064 are the closest lines to the Proposed Wellsite WR 325-C (Figure C-2). 

The Tophole Prognosis Chart (Figure C-1) shows the crossline annotated with calculated depths to the 

various horizons and predicted lithology of the sequences, along with their potential for shallow water 

flow and shallow gas. 
Project No. 0211-1878

 3 Proposed Well WR 325-C 

The top of salt is estimated to be approximately 1,448 ft below the mudline (bml) at this location. The 

relatively thin overburden is divided into five units or sequences. The sequences represent variations in 

depositional environments and possible changes in soil strength and composition. 

The surficial unit, Unit 1 (Seafloor to Horizon A), to approximately 140 ft bml, will consist of mud-rich 

hemipelagic and thin mass-transport deposits. The soils at the seabed are likely to be soft high water 

content silty clays. The shear strength of the sediments will increase with depth corresponding to a 

decrease in water content. Stiff, overconsolidated sediments have been encountered in some areas along 

the lower continental slope above shallow salt sheets. Some of these areas generally have experienced 

erosion from strong bottom currents. No evidence of furrows or other erosional seabed features are 

identified around the proposed wellsite. However, overconsolidated sediments have occurred near the 

seafloor because of uplift and erosion of the section caused by the emplacement of the salt mass. Scout 

tickets indicate the surface casing in the offset well WR 285-1 was set at ~251 ft while the surface casing 

at WR 372-1 was 324 ft. It is not known whether the difference in casing depths were the result of 

variable soil conditions or the engineering parameters of the different rigs and drilling programs. 

The base of the surficial sequence (Unit 1) is Horizon 10 which is a continuous prominent reflecting 

horizon mapped throughout the study area (Figure C-1 and C-2). Units 2 and 3, between Horizons 10 and 

20 and Horizons 20 and 30 respectively, generally consist of relatively continuous stratified reflections. 

These units will also be mud-rich and consist of hemipelagic, turbidite, and mass-transport deposits. 

Slightly higher amplitudes in Unit 3 suggest the presence of thin sand seams.

Unit 4, between Horizons 30 and 40, generally consists of low-amplitude, discontinuous to chaotic 

reflections. This is predominantly a mud-rich, mass-transport complex. Occasional sand pockets or 

seams are possible within this unit but are not likely beneath Proposed Wellsite WR 325-C. 

Unit 5 occurs between Horizon 40 and the top of salt (Figures C-1 and C-2). Reflections within this 

sequence are layered and are of moderate amplitude. Reflection continuity varies from parallel and 

continuous to discontinuous to chaotic. The deterioration in continuity reflects distortion of the section 

by faulting and folding of the unit above the shallow salt sheet and not a change in depositional 

environment. Unit 5 probably consists of turbidites interlayered with thin mass-transport deposits. The 

sequence may have been part of a slope-fan complex. The turbidites will consist of alternating layers of 

clay, silt, and sand. The relatively high-amplitude of the reflections in general and the distribution of 

bright spots within the sequence suggest that thin sand layers are possible. The unit is highly fractured by 

faulting, indicating that high pore water pressures are not likely to be encountered. No high-amplitude 

events occur beneath the proposed location within this unit. 

The top of salt at WR 325-C is at -7,798 ft subsea (1,448 ft bml). The salt surface dips to the southwest at 

approximately 4.0°. 

Faults

Several seafloor faults occur to the east of Proposed Wellsite WR 325-C (Map C-4). The closest fault is 

250 ft to the east. The fault is downthrown away from the wellsite. The “scarp” created by this fault only 

amounts to an increase in seafloor slope of 2° to 5° which is a gentle flexure of the seabed. The fault is 

probably inactive and covered by a Holocene-aged pelagic drape. 

The wellbore will intersect two fault planes at depth (Figures C-1 and C-2). The shallowest fault will be 

encountered at 660 ft bml while the deeper fault will be at 1,024 ft bml. These faults do not extend to the 

seafloor and are buried by over 400 ft of sediment. Therefore, these faults have been inactive for a 

considerable amount of time. No shallow gas anomalies are associated with these fault planes; however, 

engineers should be aware that, on occasion, fault planes can be zones of lost circulation. The shallow 

fault (660 ft bml) will be encountered along the base of Unit 3 which is primarily a mud-rich turbidite 

sequence. The deeper fault, at 1,024 ft bml, will be crossed in along the base of Unit 4. Unit 4 consists 

of discontinuous to chaotic mass-transport sediments. Unit 4 is considered to have mud-rich sediments.
Project No. 0211-1878

 4 Proposed Well WR 325-C 

Shallow Water Flow

The sedimentary section above the salt surface is 1,448 ft thick. Unit 5, between 1,034 ft to 1,428 ft bml, 

is a turbidite sequence possibly containing thin sand layers. However, the unit is highly faulted and 

fractured and possibly experienced erosion caused by uplift during emplacement of the salt sheet. High 

pore water pressures existing within this unit after deposition has likely dissipated during the period of 

active salt tectonics. 

In general, shallow water flow incidents have not been reported in the Walker Ridge area (BOEMRE, 

2011). 

Shallow Gas 

The well path will not penetrate any high-amplitude events between the seafloor and top of salt (Figures 

C-1 and C-2). The potential for shallow gas accumulations beneath Proposed Wellsite WR 325-C is 

minimal. 

Power Spectrum 

In accordance with NTL 2008-G04 and NTL 2008-G05 (MMS 2008a,b), we have extracted the power 

spectrum diagram (Figure C-3) from the 3-D seismic data cube. The extraction was generated within a 

500-ft radius of the intersection of the inlines and crosslines at the proposed wellsite. We converted the 

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

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

Figure C-3 Power Spectrum Chart Based on 3-D Data Volume Within 500-ft Radius of Proposed Wellsite C, Walker Ridge Block 325.
Project No. 0211-1878

 5 Proposed Well WR 325-C 

Closing

The seafloor at Proposed Wellsite WR 325-C, Walker Ridge Block 325 (OCS-G-32673), appears suitable 

for exploration drilling operations. No major hazards or constraints are defined by the 3-D data at the 

proposed location. 

We appreciate the opportunity to be of service to Woodside Energy (USA) Inc., and look forward to 

working closely with you on other projects. 

Sincerely,

GEOSCIENCE EARTH & MARINE

SERVICES, INC.®

Thomas W. Neurauter Ph. D. Daniel Lanier

Senior Marine Geologist Vice-President/Marine Geologist

Attachments (3 Figures, 4 Maps)

Distribution:

Mr. Douglas Lumpkin Mandeville, LA (3) 

References:

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

Bureau of Ocean Energy Management, Regulation, and Enforcement, 2011, ASCII Data Files, published on the BOEMRE Gulf of Mexico 

Region Homepage, <http://www.gomr.boemre.gov/homepg/pubinfo/freeasci/freedesc.html>, Accessed February, 2011. 

Minerals Management Service, 2005, Notice to lessees and operators of federal oil, gas, and sulphur leases and pipeline right-of-way holders in 

the outer continental shelf, Gulf of Mexico OCS region; archaeological resource surveys and reports, U. S. Department of the Interior, Minerals 

Management Service, Gulf of Mexico, NTL 2005-G07. Effective Date July 1, 2005.

Minerals Management Service, 2008a, Notice to lessees and operators of federal oil, gas, and sulfur leases and pipeline right-of-way holders in 

the outer continental shelf, Gulf of Mexico OCS region; information requirements for Exploration Plans and Development Operations 

Coordination Documents, U. S. Department of the Interior, Minerals Management Service, Gulf of Mexico, NTL 2008-G04. Effective Date May 

01, 2008.

Minerals Management Service, 2008b, Notice to lessees and operators of federal oil, gas, and sulfur leases and pipeline right-of-way holders in 

the outer continental shelf, Gulf of Mexico OCS region; shallow hazards program, U. S. Department of the Interior, Minerals Management 

Service, Gulf of Mexico, NTL 2008-G05. Effective Date May 01, 2008.

Minerals Management Service, 2008c, Notice to lessees and operators of federal oil, gas, and sulphur leases in the outer continental shelf, Gulf of 

Mexico OCS region; remotely operated vehicle surveys in deepwater, U. S. Department of the Interior, Minerals Management Service, Gulf of 

Mexico, NTL 2008-G06. Effective Date May 26, 2008.

Minerals Management Service, 2008d, Notice to lessees and operators of federal oil and gas leases and pipeline right-of-way holders on the outer 

continental shelf, Gulf of Mexico OCS region, Revisions to the list of OCS lease blocks requiring archaeological resource surveys and reports: 

U. S. Department of the Interior, Minerals Management Service, Gulf of Mexico, NTL 2008-G20. Effective Date October 20, 2008.

Minerals Management Service, 2009a, Notice to lessees and operators of federal oil and gas leases and pipeline right-of-way holders on the outer 

continental shelf, Gulf of Mexico OCS region, Military Warning and Water Test Areas: U. S. Department of the Interior, Minerals Management 

Service, Gulf of Mexico, NTL 2009-G06. Effective Date April 22, 2009.

Minerals Management Service, 2009b, Notice to lessees and operators of federal oil and gas leases in the outer continental shelf, Gulf of Mexico 

OCS region, deepwater benthic communities: U. S. Department of the Interior, Minerals Management Service, Gulf of Mexico, NTL 2009-G40. 

Effective Date: January 27, 2010.
10615 SHADOW WOOD DRIVE

SUITE 200

HOUSTON, TEXAS 77043

Phone: (713) 468-1410 

Fax: (713) 468-1438

E-mail: gems@gemsinc.com

April 2, 2012 Project No. 0312-2069

Woodside Energy (USA) Inc. 

Sage Plaza, Suite 1300

5151 San Felipe 

Houston, TX 77056 

Attention: Mr. Douglas Lumpkin 

Site Clearance Letter 

Proposed Wellsite D 

Block 325 (OCS-G-32673) 

Walker Ridge Area

Gulf of Mexico

Woodside Energy (USA) Inc., (Woodside) proposes an exploration wellsite in Walker Ridge Block 325

(OCS G-32673). This letter addresses specific seafloor and subsurface geologic and stratigraphic 

conditions to the top of salt at approximately 1,464 ft below the mudline (bml) at the Proposed Wellsite 

WR 325-D location. The following discussion is based on findings provided within the geohazard report

“Geologic and Stratigraphic Assessment, Block 325 (OCS G-32673), Walker Ridge Area, Gulf of Mexico” 

(GEMS Report No. 0608-1503). Woodside provided the following coordinates: 

Proposed Wellsite WR 325-D

Spheroid & Datum: Clarke 1866, NAD27

Projection: UTM Zone 15 North Block Calls Inline/Crossline

X: 2,264,384 ft Latitude: 26.6201361226557o N 1,683 ft FSL IN 10943

Y: 9,664,083 ft Longitude: 91.0897256932603o W 736 ft FEL XL 12045

Woodside plans to drill this well using a dynamically positioned drilling vessel. Our assessment addresses 

the seafloor conditions within a 2,000 ft radius around the proposed well location. 

Attachments

The 1:12,000 scale maps accompanying this letter were extracted from the main report’s original maps and 

3-D data volume. The maps and figures (listed below) are centered on the proposed well location. 

Map WR 325-D-1: Bathymetry Map

Map WR 325-D-2: Enhanced Seafloor Rendering 

Map WR 325-D-3: Amplitude-Enhanced Seafloor Rendering 

Map WR 325-D-4: Geologic Features Map

Figure D-1: Tophole Prognosis Chart, Proposed Wellsite D, Walker Ridge Block 325 

Figure D-2: Inline 10943and Crossline 12045 Showing Conditions Beneath Proposed 

Wellsite D, Walker Ridge Block 325 
Project No. 0312-2069

 2 Proposed Well WR 325-D 

NTL Requirements

The following report complies with the Bureau of Ocean Energy Management (BOEM, formerly MMS) 

Notice to Lessees (NTL’s) 2008-G04, 2008-G05, and 2009-G40 (MMS, 2008a,b and 2010). The operator 

will be required to follow NTL’s 2008-G04 and -G06 with respect to an ROV monitoring survey as well as 

pre- and post-spud ROV visual inspection surveys (MMS, 2008b and 2008c). The Federal lease block 

WR 325 is not considered archaeologically significant (NTL 2011-JOINT-G01, BOEM, 2011); therefore, 

requirements set forth in NTL 2005-G07 (MMS, 2005) are not applicable in terms of surveys and 

assessments in high-probability areas. However, pursuant to the Pre-Seabed Disturbance Survey Mitigation 

issued by BOEMRE (BOEMRE, 2011), an archaeological assessment of the site must be performed prior to 

any bottom disturbing activities. 

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

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

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

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

the inline and crossline at the proposed wellsite location. We converted the amplitude vs. frequency 

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

described by J. A. Coffeen, 1978. 

Figure D-3 Power Spectrum Chart Based on 3-D Data Volume Within 500-ft Radius of Proposed Wellsite D, Walker Ridge Block 325.

Water Depth and Seafloor Conditions

The water depth at the proposed location is -6,346 ft (Map D-1 and Figure D-1). The seafloor slopes to the 

southwest at a gradient of 2.5° (4.4%). 

WR 325-D is situated above a shallow salt sheet. The overburden above the top of salt is approximately 

1,464 ft thick (Figures D-1 and D-2). The seafloor topography mimics the folded and faulted salt surface. 

Faults affect the seafloor east and west of the proposed location (Figure D-2 and Maps D-1 through D-4). 

The closest offset is approximately 400 ft to the southwest. The fault is downthrown toward the proposed 
Project No. 0312-2069

 3 Proposed Well WR 325-D 

location. The well bore will intersect a branch of the fault just above Horizon 20, approximately 396 ft bml 

(Figure D-1). A second fault that extends to the seafloor occurs approximately 435 ft to the northeast of 

the proposed location. This fault is downthrown away from the proposed wellsite; therefore, the wellbore 

will not intersect the fault plane. 

Deepwater Benthic Communities

There is no evidence of hydrocarbon seepage within 2,000 ft of the proposed location. Therefore, the 

potential for high-density chemosynthetic or other deepwater benthic communities within 2,000 ft of the 

proposed location is negligible. The Amplitude-Enhanced Surface Rendering (Map D-3) shows normal or 

ambient amplitudes along the seabed near the proposed wellsite. 

The Enhanced Surface Rendering and Amplitude-Enhanced Surface Rendering show few indications of 

seepage-related features within the area examined for this evaluation. A cluster of small mud mounds 

occur in the southwest corner of WR 325 (GEMS report, Maps 2 through 4). The small mounds may be 

seepage related and therefore have the potential for supporting chemosynthetic communities. However, the 

closest feature is approximately 11,500 ft from the proposed location. These mounds will not be affected 

by the planned dynamically positioned drill rig at the Proposed WR 325-D wellsite. 

Man-Made Features

At this time, no wells or oilfield infrastructure occur within WR 325. In addition, no shipwrecks or other 

man-made debris are reported in the vicinity. The nearest exploration well is in WR 371 approximately 6 

miles to the southeast of the Proposed Wellsite WR 325-D. 

Stratigraphy 

Inline 10943 and Crossline 12045 are the closest lines to the Proposed Wellsite WR 325-D (Figure D-2). 

The Tophole Prognosis Chart (Figure D-1) shows the crossline annotated with calculated depths to the 

various horizons and predicted lithology of the sequences, along with their potential for shallow water flow 

and shallow gas. 

The top of salt is estimated to be approximately 1,464 ft below the mudline (bml) at this location. The 

relatively thin overburden is divided into five units or sequences. The sequences represent variations in 

depositional environments and possible changes in soil strength and composition. 

The surficial unit, Unit 1 (Seafloor to Horizon A), to approximately 135 ft bml, will consist of mud-rich 

hemipelagic and thin mass-transport deposits. The soils at the seabed are likely to be soft high water 

content silty clays. The shear strength of the sediments will increase with depth corresponding to a 

decrease in water content. Stiff, overconsolidated sediments have been encountered in some areas along 

the lower continental slope above shallow salt sheets. Some of these areas generally have experienced 

erosion from strong bottom currents. No evidence of furrows or other erosional seabed features are 

identified around the proposed wellsite. However, overconsolidated sediments have occurred near the 

seafloor because of uplift and erosion of the section caused by the emplacement of the salt mass. Scout 

tickets indicate the surface casing in the offset well WR 285-1 was set at ~251 ft while the surface casing 

for the WR 372-1 well was 324 ft. It is not known whether the difference in casing depths were the result 

of variable soil conditions or the engineering parameters of the different rigs and drilling programs. 

The base of the surficial sequence (Unit 1) is Horizon 10 which is a continuous prominent reflecting 

horizon mapped throughout the study area (Figure D-1 and D-2). Units 2 and 3, between Horizons 10 and 

20 and Horizons 20 and 30 respectively, generally consist of relatively continuous stratified reflections. 

These units will also be mud-rich and consist of hemipelagic, turbidite, and mass-transport deposits. 

Slightly higher amplitudes in Unit 3 suggest the presence of thin sand seams.
Project No. 0312-2069

 4 Proposed Well WR 325-D 

Unit 4, between Horizon 30 and Horizon 40, generally consists of low-amplitude, discontinuous to chaotic 

reflections. This is predominantly a mud-rich, mass-transport complex. Occasional sand pockets or seams 

are possible within this unit but are not likely beneath proposed location WR 325-D. 

Unit 5 occurs between Horizon 40 and the top of salt (Figures D-1 and D-2). Reflections within this 

sequence are layered and are of moderate amplitude. Reflection continuity varies from parallel and 

continuous to discontinuous to chaotic. The deterioration in continuity reflects distortion of the section by 

faulting and folding of the unit above the shallow salt sheet and not a change in depositional environment. 

Unit 5 probably consists of turbidites interlayered with thin mass-transport deposits. The sequence may 

have been part of a slope-fan complex. The turbidites will consist of alternating layers of clay, silt, and 

sand. The relatively high-amplitude of the reflections and the distribution of bright spots within the 

sequence suggest that thin sand layers are possible. The unit is highly fractured by faulting, indicating that 

high pore water pressures are not likely to be encountered. No high-amplitude events occur beneath the 

proposed location within this unit. 

The top of salt at Proposed Wellsite WR 325-D is at -7,810 ft subsea (1,464 ft bml). The salt surface dips 

to the south at approximately 7.5°.

Faults

As mentioned previously, the proposed wellsite occurs between two faults that extend to the seabed (Figure 

D-1 and Map D-4). The closest fault is approximately 400 ft to the southwest. The second fault is 

approximately 435 ft to the northeast. The “escarpments” created by these faults amount to an increase in 

seafloor slope of 3° to 7° which is a gentle flexure of the seabed. The faults are probably inactive and 

covered by a Holocene-aged pelagic drape. 

At depth the wellbore will intersect two fault planes at 396 ft bml and 810 ft bml (Figures D-1 and D-2). 

These faults do not extend to the seafloor but a branch of one offset is the fault that extends to the seafloor 

to the southwest of the location. The low seafloor gradient of the seafloor faults and the burial of the other 

fault indicate that fault motion is extremely slow or has been inactive for a considerable amount of time. 

No shallow gas anomalies are associated with these fault planes; however, engineers should be aware that, 

on occasion, fault planes can be zones of lost circulation. The shallow fault will be encountered near the 

base of Unit 2 a sequence of mud-rich hemipelagic and mass-transport deposits. The deeper fault (810 ft 

bml) will be encountered in Unit 4 which is a mud-rich mass-transport sequence. 

Shallow Water Flow

The sedimentary section above the salt surface is 1,464 ft thick. Unit 5, between 997 ft to 1,464 ft bml, is a 

turbidite sequence possibly containing thin sand layers. However, the unit is highly faulted and fractured 

and possibly experienced erosion caused by uplift during emplacement of the salt sheet. High pore water 

pressures existing within this unit after deposition has likely dissipated during the period of active salt 

tectonics. 

In general, shallow water flow incidents have not been reported in the Walker Ridge area (BOEM, 2012). 

Shallow Gas 

The well path will not penetrate any high-amplitude events between the seafloor and top of salt (Figures D1 and D-2). The potential for shallow gas accumulations beneath Proposed Wellsite WR 325-D is minimal. 

Closing

The seafloor at Proposed Wellsite WR 325-D, Walker Ridge Block 325 (OCS-G-32673), appears suitable 

for exploration drilling operations. No major hazards or constraints are defined by the 3-D data at the 

proposed location. 
Project No. 0312-2069

 5 Proposed Well WR 325-D 

We appreciate the opportunity to be of service to Woodside Energy (USA) Inc., and look forward to 

working closely with you on other projects. 

Sincerely,

GEOSCIENCE EARTH & MARINE

SERVICES, INC.®

Thomas W. Neurauter Ph. D. Daniel Lanier 

Senior Marine Geologist Vice-President/Marine Geologist

Attachments (3 Figures, 4 Maps)

Distribution:

Mr. Douglas Lumpkin Houston, TX (3) 

References:

Bureau of Ocean Energy Management, Regulation, and Enforcement (BOEMRE), 2011, Pre-seabed disturbance survey mitigation, 

released by BOEMRE in March 2011.

Bureau of Ocean Energy Management (BOEM), 2011, Notice to lessees and operators (NTL) of federal oil and gas leases and 

pipeline right-of-way (ROW) holders on the outer continental shelf (OCS); Revisions to the list of OCS lease blocks requiring 

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

Environmental Enforcement, Gulf of Mexico OCS Region (GOMR), NTL 2011-JOINT-G01. Effective Date December 29, 2011.

Bureau of Ocean Energy Management (BOEM), 2012, ASCII data files, published on the BOEM Gulf of Mexico Region homepage, 

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

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

Geoscience Earth & Marine Services, Inc.® (GEMS), 2008, Geologic and stratigraphic assessment, Block 325, Walker Ridge Area, 

Gulf of Mexico, Project No. 0608-1503. 

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

holders in the outer continental shelf, Gulf of Mexico OCS region, Archaeological resource surveys and reports: U. S. Department of 

the Interior, Minerals Management Service, Gulf of Mexico, NTL 2005-G07.

Minerals Management Service, 2008a, Notice to lessees and operators of federal oil, gas, and sulphur leases and pipeline right-of-way 

holders in the outer continental shelf, Gulf of Mexico OCS region, shallow hazards requirements: U. S. Department of the Interior, 

Minerals Management Service, Gulf of Mexico, NTL 2008-G05.

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

holders in the outer continental shelf, Gulf of Mexico OCS region, information requirements for exploration plans and development 

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

G04.

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

shelf, Gulf of Mexico OCS region; remotely operated vehicle surveys in deepwater, U. S. Department of the Interior, Minerals 

Management Service, Gulf of Mexico, NTL 2008-G06.

Minerals Management Service, 2009, Notice to lessees and operators of federal oil and gas leases and pipeline right-of-way holders 

on the outer continental shelf, Gulf of Mexico OCS region, Military Warning and Water Test Areas: U. S. Department of the Interior, 

Minerals Management Service, Gulf of Mexico, NTL 2009-G06. Effective Date April 22, 2009. 

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

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

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

 

Appendix F 

Air Quality Review
EXPLORATION PLAN (EP)

AIR QUALITY SCREENING CHECKLIST

COMPANY Woodside Energy

AREA WR

BLOCK 325

LEASE 32673

PLATFORM

WELL A-D

COMPANY CONTACT Debra K. Benoit

TELEPHONE NO. 713-401-0083

REMARKS debra.benoit@WoodsideEnergy.com
EMISSIONS CALCULATIONS 1ST YEAR

COMPANY AREA BLOCK LEASE PLATFORM WELL CONTACT PHONE REMARKS

Woodside Energy WR 325 32673 A-D Debra K. Benoit 713-401-0083

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

Diesel Engines HP GAL/HR GAL/D

Nat. Gas Engines HP SCF/HR SCF/D

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

DRILLING PRIME MOVER>600hp diesel 61200 2955.96 70943.04 24 151 43.14 197.89 1482.82 44.48 323.52 78.16 358.57 2686.87 80.61 586.23

PRIME 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 0.00

PRIME 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 0.00

PRIME 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 0.00

BURNER diesel 0 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

AUXILIARY EQUIP<600hp diesel 0 0 0.00 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

VESSELS>600hp diesel(crew) 1800 86.94 2086.56 8 129 1.27 5.82 43.61 1.31 9.52 0.66 3.01 22.58 0.68 4.93

VESSELS>600hp diesel(supply) 2100 101.43 2434.32 12 65 1.48 6.79 50.88 1.53 11.10 0.57 2.64 19.76 0.59 4.31

VESSELS>600hp diesel(supply) 2100 101.43 2434.32 12 65 1.48 6.79 50.88 1.53 11.10 0.57 2.64 19.76 0.59 4.31

No Tugs Required VESSELS>600hp diesel(tugs-2) 0 0 0.00 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

FACILITY 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 0.00

INSTALLATION 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 0.00

VESSELS>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 0.00

VESSELS>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 0.00

MISC. BPD SCF/HR COUNT

TANK- 0 0 0 0.00 0.00

DRILLING OIL BURN 0 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

WELL TEST GAS FLARE 0 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

2013 YEAR TOTAL 47.37 217.29 1628.19 48.85 355.24 79.97 366.86 2748.96 82.47 599.77

EXEMPTION 

CALCULATION

DISTANCE FROM LAND IN 

MILES 5494.50 5494.50 5494.50 5494.50 102282.55

165.0
COMPANY AREA BLOCK LEASE PLATFORM WELL CONTACT PHONE REMARKS

Woodside Energy WR 325 32673 A-D Debra K. Benoit 713-401-0083

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

Diesel Engines HP GAL/HR GAL/D

Nat. Gas Engines HP SCF/HR SCF/D

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

DRILLING PRIME MOVER>600hp diesel 61200 2955.96 70943.04 24 151 43.14 197.89 1482.82 44.48 323.52 78.16 358.57 2686.87 80.61 586.23

PRIME 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 0.00

PRIME 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 0.00

PRIME 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 0.00

BURNER diesel 0 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

AUXILIARY EQUIP<600hp diesel 0 0 0.00 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

VESSELS>600hp diesel(crew) 1800 86.94 2086.56 8 129 1.27 5.82 43.61 1.31 9.52 0.66 3.01 22.58 0.68 4.93

VESSELS>600hp diesel(supply) 2100 101.43 2434.32 12 65 1.48 6.79 50.88 1.53 11.10 0.57 2.64 19.76 0.59 4.31

VESSELS>600hp diesel(supply) 2100 101.43 2434.32 12 65 1.48 6.79 50.88 1.53 11.10 0.57 2.64 19.76 0.59 4.31

No Tugs Required VESSELS>600hp diesel(tugs-2) 0 0 0.00 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

FACILITY 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 0.00

INSTALLATION 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 0.00

VESSELS>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 0.00

VESSELS>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 0.00

MISC. BPD SCF/HR COUNT

TANK- 0 0 0 0.00 0.00

DRILLING OIL BURN 0 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

WELL TEST GAS FLARE 0 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

2014 YEAR TOTAL 47.37 217.29 1628.19 48.85 355.24 79.97 366.86 2748.96 82.47 599.77

EXEMPTION 

CALCULATION

DISTANCE FROM LAND IN 

MILES 5494.50 5494.50 5494.50 5494.50 102282.55

165.0
COMPANY AREA BLOCK LEASE PLATFORM WELL CONTACT PHONE REMARKS

Woodside Energy WR 325 32673 A-D Debra K. Benoit 713-401-0083

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

Diesel Engines HP GAL/HR GAL/D

Nat. Gas Engines HP SCF/HR SCF/D

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

DRILLING PRIME MOVER>600hp diesel 61200 2955.96 70943.04 24 151 43.14 197.89 1482.82 44.48 323.52 78.16 358.57 2686.87 80.61 586.23

PRIME 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 0.00

PRIME 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 0.00

PRIME 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 0.00

BURNER diesel 0 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

AUXILIARY EQUIP<600hp diesel 0 0 0.00 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

VESSELS>600hp diesel(crew) 1800 86.94 2086.56 8 129 1.27 5.82 43.61 1.31 9.52 0.66 3.01 22.58 0.68 4.93

VESSELS>600hp diesel(supply) 2100 101.43 2434.32 12 65 1.48 6.79 50.88 1.53 11.10 0.57 2.64 19.76 0.59 4.31

VESSELS>600hp diesel(supply) 2100 101.43 2434.32 12 65 1.48 6.79 50.88 1.53 11.10 0.57 2.64 19.76 0.59 4.31

No Tugs Required VESSELS>600hp diesel(tugs-2) 0 0 0.00 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

FACILITY 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 0.00

INSTALLATION 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 0.00

VESSELS>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 0.00

VESSELS>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 0.00

MISC. BPD SCF/HR COUNT

TANK- 0 0 0 0.00 0.00

DRILLING OIL BURN 0 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

WELL TEST GAS FLARE 0 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

2015 YEAR TOTAL 47.37 217.29 1628.19 48.85 355.24 79.97 366.86 2748.96 82.47 599.77

EXEMPTION 

CALCULATION

DISTANCE FROM LAND IN 

MILES 5494.50 5494.50 5494.50 5494.50 102282.55

165.0
COMPANY AREA BLOCK LEASE PLATFORM WELL CONTACT PHONE REMARKS

Woodside Energy WR 325 32673 A-D Debra K. Benoit 713-401-0083

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

Diesel Engines HP GAL/HR GAL/D

Nat. Gas Engines HP SCF/HR SCF/D

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

DRILLING PRIME MOVER>600hp diesel 61200 2955.96 70943.04 24 152 43.14 197.89 1482.82 44.48 323.52 78.68 360.95 2704.66 81.14 590.11

PRIME 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 0.00

PRIME 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 0.00

PRIME 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 0.00

BURNER diesel 0 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

AUXILIARY EQUIP<600hp diesel 0 0 0.00 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

VESSELS>600hp diesel(crew) 1800 86.94 2086.56 8 130 1.27 5.82 43.61 1.31 9.52 0.66 3.03 22.73 0.68 4.96

VESSELS>600hp diesel(supply) 2100 101.43 2434.32 12 65 1.48 6.79 50.88 1.53 11.10 0.58 2.65 19.89 0.60 4.34

VESSELS>600hp diesel(supply) 2100 101.43 2434.32 12 65 1.48 6.79 50.88 1.53 11.10 0.58 2.65 19.89 0.60 4.34

No Tugs Required VESSELS>600hp diesel(tugs-2) 0 0 0.00 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

FACILITY 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 0.00

INSTALLATION 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 0.00

VESSELS>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 0.00

VESSELS>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 0.00

MISC. BPD SCF/HR COUNT

TANK- 0 0 0 0.00 0.00

DRILLING OIL BURN 0 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

WELL TEST GAS FLARE 0 0 0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

2016 YEAR TOTAL 47.37 217.29 1628.19 48.85 355.24 80.50 369.29 2767.17 83.01 603.75

EXEMPTION 

CALCULATION

DISTANCE FROM LAND IN 

MILES 5494.50 5494.50 5494.50 5494.50 102282.55

165.0
SUMMARY

COMPANY AREA BLOCK LEASE PLATFORM WELL

Woodside EnergWR 325 32673 A-D

Emitted Substance

Year

PM SOx NOx VOC CO

2013 79.97 366.86 2748.96 82.47 599.77

2014 79.97 366.86 2748.96 82.47 599.77

2015 79.97 366.86 2748.96 82.47 599.77

2016 80.50 369.29 2767.17 83.01 603.75

2017 0.00 0.00 0.00 0.00 0.00

2018 0.00 0.00 0.00 0.00 0.00

2019 0.00 0.00 0.00 0.00 0.00

2020 0.00 0.00 0.00 0.00 0.00

2021 0.00 0.00 0.00 0.00 0.00

2022 0.00 0.00 0.00 0.00 0.00

Allowable 5494.50 5494.50 5494.50 5494.50 102282.55
 

 

Appendix G 

Oil Spill Response Discussion

Oil Spill Response Certification
SPILL RESPONSE DISCUSSION 

For the purpose of NEPA and Coastal Zone Mana gement Act analysis, the largest spill volum e 

originating from the proposed activity would be a well b lowout during drilling operations, 

estimated to be 31,190 barrels of crude oil with an API gravity of 23.9°. 

Land Segment and Resource Identification

Trajectories of a spill a nd the prob ability of it im pacting a land segm ent have bee n projec ted 

utilizing information in the BS EE Oil Spill R isk Analysis Model (OSRAM) for the Central and 

Western Gulf of Mexico available on the BSEE website. The results are shown in Figure 1. The 

BSEE OSRAM identifies a 3% proba bility of im pact to the s horelines of Ca meron Parish, 

Louisiana within 30 days. Cameron Parish includes the east side of Sabine Lake, Sabine National 

Wildlife Refuge, Calcasieu Lake, Lacassine Nationa l Wildlife Refuge (inland) and Grand Lake. 

Cameron Parish also includes the area along the coastline from Sabine Pass to Big Constance 

Lake in Rockefeller Wildlife Refuge. This region is co mposed of open public beaches, 

marshlands and swam ps. It serves as a habita t for num erous birds, finf ish and other anim als, 

including several rare, threatened and endangered species. 

Response

Woodside Energy (USA) Inc. will make every effort to respond to the Wo rst Case Discharge as 

effectively as practicable. A description of the response equipment under contract to contain and 

recover the Worst Case Discharge is shown in Figure 2.

Using the estim ated chem ical and physical charact eristics of crude oil, an ADIOS weathering 

model was run on a similar product from the ADIO S oil database. The results indicate 28% or 

approximately 8,733 barrels of crude oil would be evaporated/dispersed within 24 hours, with 

approximately 22,457 barrels remaining. 

Spill Response WR 325 Barrels of Oil 

WCD Volume 31,190

Less 28% natural evaporation/dispersion 8,733

Remaining volume 22,457

Daily dispersant capability 7,540 

Figure 2 o utlines equ ipment, pers onnel, m aterials and su pport ves sels as well as tem porary 

storage equipment available to respond to a spill of approx imately 22,457 barrels. The volum e 

accounts for the am ount remaining after evaporatio n/dispersion at 24 hours. The list estim ates 

individual times needed for procurement, load out, travel time to the site and deployment. Figure 

2 also indicates how operations will be supported. 

Woodside Energy (USA) Inc.’s Oil Spill Response Plan incl udes alternative response 

technologies such as dispersants and in-situ burn. Strategies will be decided by Unified 
Command based on size of the spi ll, weath er and potential im pacts. If aerial d ispersants are 

utilized, 8 sorties (9,600 gallons) from two of the DC-3 aircrafts and 4 sorties (8,000 gallons) 

from the Basler aircraf t would provide a dail y dispersan t capability o f 7,540 barrels. If the 

conditions are favorable for in-situ burning, the proper approvals have been obtained and the 

proper plan ning is in p lace, in -situ burning of oil m ay be attem pted. Slick containm ent boom 

would be immediately called out and on-scene as soon as possible. Offshore response strategies 

may include attempting to skim utilizing the HOSS Barge and three Fast Response Units, with a 

total derated skimming capacity of 55,753 barrels. Temporary storage associated with skimm ing 

equipment equals 4,500 barrels. If additional storage is needed, three 20,000 barrel storage barge 

may be mobilized and centrally located to provi de temporary storage allowing the skimm ers to 

stay in the area of operations as much as possible. Safety is first priority. Air monitoring will 

be accomplished and operations deemed safe prior to any containment/skimming attempts. 

If the spill went unabated, s horeline impact in Ca meron Parish, Louisiana would depend upon 

existing environm ental conditions. Shoreline prot ection would include the use of CGA’s near 

shore and shallow water skimm ers with a tota led derated skimm ing capacity of 13,253 barrels. 

Temporary storage associated with skimming equipment equals 256 barrels. If additional storage 

is needed, a 23,000 barrel s torage barge m ay be mobilized and centrally located to prov ide 

temporary storage a llowing the sk immers to stay in the area of operation s as m uch as possib le. 

Onshore response m ay include the d eployment of shoreline boom on beach areas, o r protection 

and sorbent boom on vegetated areas. A Mas ter Service Agreement with Oil Mop will ensure 

access to 3 0,000 feet of 18” shoreline p rotection boom . Figure 2 o utlines ind ividual tim es 

needed for procurem ent, load out, travel tim e to the site and deploym ent. Strategies would be 

based upon surveillance and real tim e trajectories that depict areas of potential impact given 

actual sea and weather conditions. The State of Louisiana Initial Oil S pill Response Plan for 

Cameron Parish and Unified Command would be consulted to ensure that environm ental and 

special eco nomic reso urces would be correctly identified and prior itized to en sure optim al 

protection. Shoreline protection strategies depict the protection response modes applicable for oil 

spill clean-up operations. The State of Louisiana Initial Oil Spill Response Plan provides detailed 

shoreline protection strategies for this area, and it describes necessary action to keep the oil spi ll 

from entering Louisiana’s coastal wetlands, based on the assumption that removal of the released 

oil will be much easier and less dam aging to fragile coastal ecosystem s if done in the open 

waters of the Gulf of M exico. Supervisory personnel have the option to modify the deploym ent 

and operation of equipm ent allowing a m ore eff ective respo nse to site-s pecific circu mstances. 

Woodside Energy (USA) Inc.’s cont ract Spill Managem ent Team holds a copy of the State of 

Louisiana Initial Oil Spill Response Plan. 

Based on the anticipated wors t cas e discharge scenario, Woodside Energy (USA) Inc. can be 

onsite with contracted o il spill recovery equipm ent with ad equate response capacity to contain 

and recover surface hydrocarbons , and prevent land im pact to the m aximum extent practicab le, 

within 48 hours (based on the equipm ent’s Eff ective Daily Recovery Capacity (EDRC)). 

Woodside Energy (USA) Inc. will continue to co mmit additional on-water m echanical recovery 

resources as well as apply dispersants and in -situ burning needed and as approved, under the 

supervision of the USCG Captain of the Port (COTP) and the Regional Response Team (RRT). 
Initial Response Considerations 

Actual actions taken during an oil spill response will be based on many factors to include but not 

be limited to: 

• Weather 

• Equipment and materials availability 

• Ocean currents and tides 

• Location of the spill 

• Product spilled 

• Amount spilled 

• Environmental risk assessments 

• Trajectory and product analysis 

• Well status, i.e., shut in or continual release 

Woodside Energy (USA) Inc. will take action to provide a safe, aggressi ve response to contain 

and recover as much of the spilled oil as quickly as it is saf e to do so. In an effort to protect the 

environment, response actions wi ll be designed to provide an “in-depth” protection strategy 

meant to recover as much oil as possible as far from environmentally sensitive areas as possible. 

Safety will take precedence over all other considerations during these operations. 

Upon notification of a spill, the following actions will be taken: 

• Information will be confirmed 

• An assessment will be made and initial objectives set 

• OSROs and appropriate agencies will be notified 

• ICS 201, Initial Report Form completed 

• Initial Safety plan will be written and published 

• Unified Command will be established 

o Overall safety plan developed to reflect the operational situation and coordinated 

objectives 

o Areas of responsibility established for Source Control and each surface operational 

site 

o On-site command and control established 

Offshore Response Actions 

Equipment Deployment

Surveillance 

• Surveillance Aircraft: within two hours of QI notification, or at first light

• Provide trained observer to provide on site status reports 

• Provide command and control platform at the site if needed 

• Continual surveillance of oil movement by remote sensing systems, aerial photography 

and visual confirmation 

• Continual monitoring of vessel assets using vessel monitoring systems 
Dispersant application assets 

• Put ASI on standby 

• With the FOSC, conduct analysis to determine appropriateness of dispersant application 

• Gain FOSC approval for use of dispersants on the surface 

• Deploy aircraft in accordance with a plan developed for the actual situation 

• Coordinate movement of dispersants, aircraft, and support equipment and personnel 

• Confirm dispersant availability for current and long range operations 

• Start ordering dispersant stocks required for expected operations 

Containment boom 

• Call out early and expedite deployment to be on scene ASAP 

• Ensure boom handling and mooring equipment is deployed with boom 

• Provide continuing reports to vessels to expedite their arrival at sites that will provide for 

their most effective containment 

• Use Vessels of Opportunity (VOO) to deploy and maintain boom 

Dedicated off-shore skimming systems 

General 

• Deployed to the highest concentration of oil 

• Assets deployed at safe distance from aerial dispersant and in-situ burn operations 

CGA HOSS Barge 

• Use in areas with heaviest oil concentrations 

• Consider for use in areas of known debris (seaweed, and other floating materials) 

CGA FRUs 

• To the area of the thickest oil 

• Use as far off-shore as allowed 

• VOOs 140’ – 180’ in length 

• VOOs with minimum of 18’ x 38’ or 23’ x 50’ of optimum deck space 

• VOOs in shallow water should have a draft of <10 feet when fully loaded 

Storage Vessels 

• Establish availability of CGA contracted assets 

• Early call out (to allow for tug boat acquisition and deployment speeds) 

• Phase mobilization to allow storage vessels to arrive at the same time as skimming 

systems 

• Position as closely as possible to skimming assets to minimize offloading time 
Vessels of Opportunity (VOO) 

• Use Woodside Energy (USA) Inc.’s contracted resources as applicable 

• Industry vessels are usually best for deployment of Vessel of Opportunity Skimming 

Systems (VOSS) 

• Acquire additional resources as needed 

• Consider use of local assets, i.e. fishing and pleasure craft 

• Expect mission specific and safety training to be required 

• Plan with the US Coast Guard for vessel inspections 

In-situ Burn assets 

• Determine appropriateness of in-situ burn operation in coordination with the FOSC and 

affected SOSC 

• Determine availability of fire boom and selected ignition systems 

• Start ordering fire boom stocks required for expected operations 

• Contact boom manufacturer to provide training if required 

• Determine assets to perform on water operation 

• Build operations into safety plan 

• Conduct operations in accordance with an approved plan 
Near Shore Response Actions 

Timing 

• Put near shore assets on standby and deployment in accordance with planning based on 

the actual situation, actual trajectories and oil budgets 

• VOO identification and training in advance of spill nearing shoreline if possible 

• Outfitting of VOOs for specific missions 

• Deployment of assets based on actual movement of oil 

Considerations 

• Water depth, vessel draft 

• Shoreline gradient 

• State of the oil 

• Use of VOOs 

• Distance of surf zone from shoreline 

Equipment Deployment 

Surveillance 

• Provide trained observer to direct skimming operations 

• Continual surveillance of oil movement by remote sensing systems, aerial photography 

and visual confirmation 

• Continual monitoring of vessel assets 

Dispersant Use 

• Generally will not be approved within 3 miles of shore or with less than 10 meters of 

water depth 

• Approval would be at Regional Response Team level (Region 6) 

Vessel Deployment 

Dedicated Near Shore skimming systems 

• FRVs 

• Egmopol and Marco SWS 

• Operate with aerial spotter directing systems to observed oil slicks 

VOO 

• Use Woodside Energy (USA) Inc.’s contracted resources as applicable 

• Industry vessels are usually best for deployment of Vessel of Opportunity Skimming 

Systems (VOSS) 

• Acquire additional resources as needed 

• Consider use of local assets, i.e. fishing and pleasure craft 

• Expect mission specific and safety training to be required 

• Plan with the US Coast Guard for vessel inspections 

• Operate with aerial spotter directing systems to oil patches 
Shoreline Protection Operations 

Response Planning Considerations 

• Environmental risk assessments (ERA) to determine priorities for area protection 

• Time to acquire personnel and equipment and their availability 

• Previous contingency planning contained in the appropriate Area Contingency Plan, and 

currently for Louisiana, The State of Louisiana Initial Oil Spill Response Plan, Deep 

Water Horizon, dated 2 May 2010 (La. OSRP) 

Actions 

Placement of boom 

• Position boom in accordance with the ERA based on the actual situation or the 

appropriate ACP 

• Assess timing of booming operations to ensure it is where it needs to be at time of 

impact. Consider: 

o Trajectories 

o Weather forecast 

o Oil Impact forecast 

o Verified spill movement 

o Boom, manpower and vessel (shallow draft) availability 

o Near shore boom and support material, (stakes, anchors, line) 

Beach Preparation 

Considerations and Actions 

• Use of a 10 mile go/no go line to determine timing of beach cleaning 

• Shoreline Cleanup and Assessment Team Reports and recommendations 

• Determination of Archeological sites and gaining authority to enter 

• Monitoring of tide tables and weather to determine extent of high tides 

• Pre cleaning of beaches by moving waste above high time lines to minimize waste 

• Staging of equipment and housing of response personnel as close to the job site as 

possible to maximize on-site work time 

• Boom tending, repair, replacement and security (use of local assets may be advantageous) 

• Constant awareness of weather and oil movement for resource redeployment as necessary 

• In-situ burn may be considered when marshes have been impacted 

• Passive clean up of marshes should considered and appropriate stocks of sorbent boom 

and/or sweep obtained 

• Earthen berms and shoreline protection boom may be considered to protect sensitive 

inland areas 
Decanting Strategy 

Recovered oil and wa ter m ixtures will typic ally se parate into d istinct phase s when lef t in a 

quiescent state. W hen s eparation occurs, the relatively clean water phase can be siphoned or 

decanted back to the recovery point with m inimal, if any, impact. Decan ting therefore increases 

the effective on-site oil storage c apacity and equipment operating time. FOSC/SOSC approval 

will be req uested p rior to decan ting operation s. This pra ctice is rou tinely used f or oil spill 

recovery. 

CGA Equipment Limitations 

The capability f or any spill respon se equipm ent, whether a dedica ted or portab le system , to 

operate in differing weather conditions will be directly in relation to the capabilities of the vessel 

the system in placed on. Most importantly, however, the decision to operate will be based on the 

judgment of the Unified Command and/or the Captain of the vessel, who will ultimately have the 

final say in te rminating opera tions. Skimm ing equipment listed below m ay have operational 

limits which exceed thos e safety thresholds. As was seen in the Deepwater Horizon (DWH) oil 

spill response, vessel skimming opera tions ceased when seas reache d 5-6 feet and vessels were 

often recalled to port when those conditions w ere exceeded. System s below are som e of the 

most up-to-date systems available and were employed during the DWH spill. 

Boom 3 foot seas, 20 knot winds 

Dispersants Winds more than 25 knots 

Visibility less than 3 nautical miles 

Ceiling less than 1,000 feet. 

FRU 8 foot seas 

HOSS Barge/OSRB 8 foot seas 

Koseq Arms 8 foot seas 

OSRV 4 foot seas 
Environmental Conditions in the GOM

Louisiana is situated between the easterly and westerly wind belts, and therefore, experien ces 

westerly winds during the wint er and easterly winds in th e summ er. Average wind speed is 

generally 14-15 m ph a long the coast. W ave he ights average 4 and 5 feet. However, during 

hurricane season, Louisiana has recorded wave heights ranging from 40 to 50 feet high and 

winds reaching speeds of 100 mph. Because much of southern Louisiana lies below sea level, 

flooding is prominent. 

Surface water temperature ranges between 70 and 80  ̊F during the summ er months. During the 

winter, the average temperature will range from 50 and 60 ̊F. 

The Atlantic and Gulf of Mexico hurricane seas on is officially from 1 June to 30 Nove mber. 

97% of all tropical activity occurs within this window. The Atlant ic basin shows a very peaked 

season from August through October, with 78% of the tropical storm days, 87% of the m inor 

(Saffir-Simpson Scale categories 1 and 2) hurricane days, and 96% of the m ajor (Saffir-Simpson 

categories 3, 4 and 5) hurricane days occurri ng then. Maxim um activity is in early to m id 

September. Once in a few years there may be a hurricane occurring "out of season" - primarily in 

May or Decem ber. Globally, September is the mo st active month and May is the least active 

month. 
FIGURE 1 

TRAJECTORY BY LAND SEGMENT 

Trajectory of a spill and the probability of it impacting a land segment have been projected 

utilizing Woodside Energy (USA) Inc.’s WC D and information in the BSEE Oil Spill 

Risk Analysis Model (OSRAM) for the Central and Western Gulf of Me xico available on 

the BSEE website using 30 day impact. The results are tabulated below. 

Area/Block OCS-G Launch 

Area 

Land Segment and/or 

Resource 

Conditional 

Probability (%) 

within 30 days 

Exploratory Drilling 

WR 325 

165 miles from shore 

G32673 C47 Matagorda County, TX 

Brazoria County, TX 

Galveston County, TX 

Jefferson County, TX 

Cameron Parish, LA 

Vermilion Parish, LA 

Terrebonne Parish, LA 

Plaquemines Parish, LA 

1 

1 

2 

1 

3 

1 

1 

1 
WCD Scenario– BASED ON WELL BLOWOUT DURING DRILLING OPERATIONS (165 miles from s

22,457 bbls of crude oil (Volume considering natural weathering) API Gravity 23.9° 

FIGURE 2 – Equipment Response Time to WR 325 

Dispersants/Surveillance 

Dispersant/Surveillance Dispersant Capacity (gal) Storage Capacity Persons Req. From Hrs to Procure Hrs to Loadout Travel to site 

CGA 

Basler 67T 2000 NA 2 Houma 1 1 1.1 3.

ASI 

DC 3 1200 NA 2 Houma 1 1 1.4 3.DC 3 1200 NA 2 Houma 1 1 1.4 3.Aero Commander NA NA 2 Houma 1 1 1.1 

Offshore Response 

Offshore Equipment No 

Staging EDRC Storage Capacity VOO Persons Required From Hrs to Procure Hrs to Loadout Hrs to GOM 

CGA 

HOSS Barge 43000 4000 3 Tugs 8 Harvey 7 0 5 

Recovered Oil Storage No 

Staging EDRC Storage Capacity VOO Persons Required From Hrs to Procure Hrs to Loadout Hrs to GOM 

Enterprise Marine Services LLC (available through contract with CGA) 

CTCo 2604 NA 20000 1 Tug 6 Amelia 4 12 4 CTCo 2605 NA 20000 1 Tug 6 Amelia 4 12 4 CTCo 2606 NA 20000 1 Tug 6 Amelia 4 12 4 
Staging Area: Fourchon

Offshore Equipment With 

Staging EDRC Storage Capacity VOO Persons Req. From Hrs to Procure Hrs to Loadout Travel to Staging 

CGA 

FRU (2) + 100 bbl Tank (4) 8502 400 2 Utility 12 Leeville 1 2 .5 FRU (1) + 100 bbl Tank (1) 4251 100 1 Utility 6 Harvey 1 2 2.75 42” Auto Boom (5000’) NA NA 10 Crew 20 Galveston 1 2 7 42” Auto Boom (10000’) NA NA 0 Crew 40 Harvey 1 2 2.75 42” Auto Boom (2500’) NA NA 6 Crew 12 Ingleside 1 2 9.5 42” Auto Boom (5000’) NA NA 10 Crew 20 Lake Charles 1 2 4 42” Auto Boom (2500’) NA NA 6 Crew 12 Pascagoula 1 2 4 1000’ Hydro-Fire Boom NA NA 8 Utility 40 Harvey 1 4 2.75 
Nearshore Response 

Nearshore Recovered Oil 

Storage No Staging EDRC Storage Capacity VOO Persons Required From Hrs to Procure Hrs to Loadout Hrs to GOM 

Enterprise Marine Services LLC (available through contract with CGA) 

CTCo 2607 NA 23000 1 Tug 6 Amelia 4 23 4 

Staging Area: Cameron 

Nearshore and Inland 

Skimmers With Staging EDRC Storage Capacity VOO Persons Req. From Hrs to Procure Hrs to Loadout Travel to Staging T

De

CGA 

SWS Egmopol 3000 100 NA 3 Galveston 1 2 3.5 SWS Egmopol 3000 100 NA 3 Houma 1 2 4 SWS Marco 3588 34 NA 3 Houma 1 2 4 SWS Marco 3588 20 NA 3 Lake Charles 1 2 1 Rope Mop 77 2 0 3 Belle Chasse 1 2 4.5 
Shoreline Protection 

Staging Area: Cameron 

Shoreline Protection 

Boom VOO Persons Req. Storage/Warehouse Location Hrs to Procure Hrs to Loadout Travel to Staging Travel to Deployment Site 

Oil Mop (available through MSA) 

10,000’ 18” Boom 4 Crew 10 New Iberia, LA 1 1 2.5 2 10,000’ 18” Boom 4 Crew 10 Houston, TX 1 1 2.5 2 10,000’ 18” Boom 4 Crew 10 Port Arthur, TX 1 1 1.25 2 

Beach Boom EDRC Storage Capacity VOO Persons Req. From Hrs to Procure Hrs to Loadout Travel to Staging T

De

CGA 

Beach Boom (2000’) NA NA NA 6 Galveston 1 2 3.5 Beach Boom (1000’) NA NA NA 4 Ingleside 1 2 6 Beach Boom (2000’) NA NA NA 6 Pascagoula 1 2 5.5 

Wildlife Response EDRC Storage Capacity VOO Persons Req. From Hrs to Procure Hrs to Loadout Travel to Staging T

De

CGA 

Wildlife Support Trailer NA NA NA 2 Houma 1 2 4 Bird Scare Guns (24) NA NA NA 2 Belle Chasse 1 2 4.5 Bird Scare Guns (12) NA NA NA 2 Galveston 1 2 3.5 Bird Scare Guns (24) NA NA NA 2 Houma 1 2 4 Bird Scare Guns (12) NA NA NA 2 Ingleside 1 2 6 Bird Scare Guns (24) NA NA NA 2 Lake Charles 1 2 1 Bird Scare Guns (24) NA NA NA 2 Pascagoula 1 2 5.5 

Response Asset Total 

Offshore EDRC 55,753 Offshore Recovered Oil Storage 64,500 Nearshore / Shallow Water EDRC 13,253 Nearshore / Shallow Water Recovered Oil Storage 23,256 




NATI(}HAL RESPONSE

co'|poRATroN

6620 CYPRESSWOOD DRlvE. STE.201

SPRING, TEXAS 77379

(281) 899-4&18 . FAX {281i 89s-4849

a SEACORcompany

Please be advised that Woodside Energy (USA) Inc. cunently has a memberchip

agreernent with National Response Corporation (NRC) as equipment provider and

the follovying contracts or agreements by way of NRC membership:

The subject contracts or membership agreements provide immediate access

to available personnelandlor eguipment on a 24-hour per day basis.

ou,/tAoro

COf, POEATE HEADQUAftTERS

3500 SUNHISE HIGHWAY. SUI?E 103

GREAT RIVER, NY 11739

(6811 224*9141 ' FAX {631} 224-sa82

REGIOHAL OFFICES

HOUSTON,TX SAN JUAN, PR

MEMPHIS, TN SEATTLE, WA

MORGAN C'TY, LA SI CRO'X, USVI

N€WYORK, NY TAMPA, FL
 

 

Appendix H 

Consistency Certification

 

 

Appendix I 

Environmental Impact Analysis
Woodside Energy (USA), Inc. (Woodside)

Supplemental/Revised Exploration Plan 

Walker Ridge Block 325 

OCS-G 32673

(A) Impact Producing Factors 

ENVIRONMENTAL IMPACT ANALYSIS WORKSHEET 

Environment 

Resources 

Impact Producing Factors (IPFs) 

Categories and Examples 

Refer to recent GOM OCS Lease Sale EIS for a more complete list of IPFs 

Emissions 

(air, noise, 

light, etc.) 

Effluents 

(muds, 

cutting, other 

discharges to 

the water 

column or 

seafloor) 

Physical 

disturbances to the 

seafloor (rig or 

anchor 

emplacements, 

etc.) 

Wastes sent 

to shore for 

treatment 

or disposal 

Accidents 

(e.g., oil 

spills, 

chemical 

spills, H2S 

releases) 

Discarded 

Trash & 

Debris 

Site-specific at Offshore 

Location 

Designated topographic features (1) (1) 

Pinnacle Trend area live bottoms (2) (2) 

Eastern Gulf live bottoms (3) (3) 

Benthic communities (4) 

Water quality X(5) X(5) 

Fisheries X(6) X(6) 

Marine Mammals X(7) X(7) X(7) X(7) 

Sea Turtles X(8) X(8) X(8) X(8) 

Air quality (9) 

Shipwreck sites (known or 

potential) 

 (10) 

Prehistoric archaeological sites (11) 

Vicinity of Offshore Location 

Essential fish habitat X(1) X(1) 

Marine and pelagic birds (2) X(2) X(2) 

Public health and safety 

Coastal and Onshore 

Beaches X(1) X(1) 

Wetlands X(2) X(2) 

Shore birds and coastal nesting 

birds 

 X(3) X(3) 

Coastal wildlife refuges X(4) X(4) 

Wilderness areas X(5) X(5) 
Footnotes for Environmental Impact Analysis Matrix 

1) Activities that may affect a marine sanctuary or topographic feature. Specifically, if the well or platform site or 

any anchors will be on the seafloor within the: 

o 4-mile zone of the Flower Garden Banks, or the 3-mile zone of Stetson Bank; 

o 1000-m, 1-mile or 3-mile zone of any topographic feature (submarine bank) protected by the Topographic 

Features Stipulation attached to an OCS lease; 

o Essential Fish Habitat (EFH) criteria of 500 ft. from any no-activity zone; or 

o Proximity of any submarine bank (500 ft. buffer zone) with relief greater than 2 meters that is not protected 

by the Topographic Features Stipulation attached to an OCS lease. 

2) Activities with any bottom disturbance within an OCS lease block protected through the Live Bottom (Pinnacle 

Trend) Stipulation attached to an OCS lease. 

3) Activities within any Eastern Gulf OCS block where seafloor habitats are protected by the Live Bottom (LowRelief) Stipulation attached to an OCS lease. 

4) Activities on blocks designated by the BOEM as being in water depths 300 meters or greater. 

5) Exploration or production activities where H2S concentrations greater than 500 ppm might be encountered. 

6) All activities t hat could result in an accidental spill of produced liquid hydrocarbons or diesel fuel that you 

determine would im pact these envi ronmental resources. If the proposed action is lo cated a sufficie nt distance 

from a resource that no impact would occur, the EIA can note that in a sentence or two. 

7) All activities that involve seafloor disturbances, including anchor emplacements, in any OCS block designated 

by the BOEM as h aving high-probability for the occurrence of shipwrecks or p rehistoric sites, in cluding such 

blocks that will be affected that are adjacent to the lease block in which your planned activity will occur. If the 

proposed activities are located a sufficient distance from a shipwreck or a prehistoric site that no impact would 

occur, the EIA can note that in a sentence or two. 

8) All activities that you determine might have an adverse effect on endangered or threatened marine mammals or 

sea turtles or their critical habitats. 

9) Production activities that involve transportation of produced fluids to shore using shuttle tankers or barges. 
(B) Analysis 

Site-Specific at Walker Ridge Block 325 

Proposed operations consist of the revision of previ ously approved Well Locations A, B and C, 

the addition of Well Location D and the drilling of these wells. 

The operations will be conducted with a dynamically positioned semi-submersible. 

1. Designated Topographic Features 

Potential IPFs on topographic features include effluents, and accidents. 

Effluents: Walker Ridge Block 325 is 93 m iles fr om the closest designated Topographic 

Features Stipulation Block (Sweet Bank); therefore, no adverse impacts are expected. 

Accidents: It is unlikely that an acciden tal su rface or sub surface spill would occur from the 

proposed activities (refer to statistics in Item 5 , W ater Quality). Oil s pills cause dam age to 

benthic organisms only if the oil contacts the organi sms. Oil from a surface spill can be driven 

into the water colum n; measurable amounts have been docum ented down to a 10 m depth. At 

this depth, the oil is found only at concentrations several orders of ma gnitude lower than the 

amount shown to have an effect on corals. Becau se the crests of topogr aphic features in the 

Northern Gulf of Mexico are foun d below 10 m, no oil from a surface sp ill could reach their 

sessile biota. Oil from a subsurface spill is not applicable due to the distance of these blocks from 

a topographic area. The activities proposed in this plan will be covered by Woodside’s Regional 

OSRP (refer to information submitted in Appendix G). 

There are no other IPFs (includi ng emissions, physical disturbances to the seafloor and wastes 

sent to shore for disposal) from the proposed activities, which could impact topographic features. 

2. Pinnacle Trend Area Live Bottoms 

Potential IPFs on pinnacle trend area live bottoms include effluents and accidents. 

Effluents: Walker Ridge Block 325 is 239 m iles from the closest live botto m (pinnacle trend) 

area; therefore, no adverse impacts are expected. 

Accidents: It is unlikely that an acciden tal su rface or sub surface spill would occur from the 

proposed activities (refer to statistics in Item 5, Water Quality). Oil spill s have the potential to 

foul benthic communities and caus e lethal and sublethal effects on live bottom organisms. Oil 

from a surface sp ill can be dr iven into the w ater colum n; m easurable am ounts have been 

documented down to a 10 m depth. At this depth, the oil is found only at concentrations several 

orders of magnitude lower than the amount shown to have an effect on m arine organisms. Oil 
from a subsurface spill is not a pplicable due to the dis tance of these blocks from a live bottom 

(pinnacle trend) area. The activ ities proposed in this p lan will be covered by Woodside’s 

Regional OSRP (refer to information submitted in Appendix G). 

There are no other IPFs (includi ng emissions, physical disturbances to the seafloor and wastes 

sent to shore for disposal) from the proposed activities which could im pact a live bottom 

(pinnacle trend) area. 

3. Eastern Gulf Live Bottoms 

Potential IPFs on Eastern Gulf live bottoms include effluents and accidents. 

Effluents: Walker Ridge Block 325 is not located in an area characterized by the existence of 

live bottoms; therefore, no adverse impacts are expected. 

Accidents: It is unlikely that an acciden tal su rface or sub surface spill would occur from the 

proposed activities (refer to statistics in Item 5, Water Quality). Oil spills cause d amage to live 

bottom organisms only if the oil con tacts the organisms. Oil from a surface spill can be driven 

into the water colum n; measurable amounts have been docum ented down to a 10 m depth. At 

this depth, the oil is found only at concentrations several orders of ma gnitude lower than the 

amount shown to have an effect on m arine inve rtebrates. Oil from a subsurface s pill is not 

applicable due to the distance of these blocks from a live bottom area. The activities proposed in 

this p lan will be cover ed by W oodside’s Regi onal OSRP (ref er to inf ormation subm itted in 

Appendix G). 

There are no other IPFs (includi ng emissions, physical disturbances to the seafloor and wastes 

sent to shore for disposal) from the proposed ac tivities which could impact an Eastern Gulf live 

bottom area. 

4. Benthic Communities 

Walker Ridge Block 325 is locate d in water depths 984 feet (300 meters) or greater. Potential 

IPFs that co uld resu lt in im pacts to benthic communities fro m the proposed activities includ e 

physical disturbances to the seafloor. 

Physical disturbances to the seafloor: A dy namically p ositioned se mi-submersible is being 

used for the proposed activ ities; therefore, only an insignificant am ount of seafloor will be 

disturbed. Because ph ysical distu rbances to the seafloor will be m inimized by the use of a 

dynamically positioned sem i-submersible, W oodside’s proposed operations in W alker Ridge 

Block 325 would not cause im pacts to benthic communities. Additionally, Walker Ridge Block 

325 is approxim ately 71 m iles from the closes t known benthic community site (BenthicGreen 

Canyon Block 287), lis ted in NTL 2009-G40. The proposed activ ities will be conducted in 
accordance with NTL 2009-G40, which will en sure that features o r areas that cou ld support 

high-density benthic communities will not be impacted. 

There are n o other IPF s (includ ing e missions, effluents, wastes sent to shore for disposal, or 

accidents) from the proposed activities which could impact benthic communities. 

5. Water Quality 

IPFs that could result in water quality degradation from the proposed operations in Walker Ridge 

Block 325 include effluents and accidents. 

 

Effluents: Levels of contaminants in drilling muds and cuttings and produced water discharges, 

discharge-rate restrictions and monitoring and toxicity testin g are regulated by the EPA NPDES 

permit, thereby elim inating m any significant bi ological o r eco logical effects. Operational 

discharges are not expected to cause significant adverse impacts to water quality. 

Accidents: Oil sp ills have the potential to alter offshore water quality; how ever, it is un likely 

that an accidental surface or subsurface spill would occur from the proposed activities. Between 

1980 and 2000, OCS operations produced 4.7 billion barrels of oil and spilled only 0.001 percent 

of this oil, or 1 bbl for every 81,000 bbl produced. The spill risk related to a diesel spill from 

drilling operations is even less. Between 1976 and 1985, (years for which da ta were collected), 

there were 80 reported diesel spil ls greater than one barrel associ ated with dr illing activities . 

Considering that there were 11,944 wells drille d, this is a 0.7 percen t probability of an 

occurrence. If a spill were to occu r, the water quality of m arine waters would be tem porarily 

affected by the disso lved com ponents and s mall oil d roplets. Disp ersion by currents and 

microbial degradation would remove the oil from the water column and dilute the constituents to 

background levels. Historically, changes in offshore water quality from oil spills have only been 

detected during the life of the spill and up to several months afterwards. Most of the components 

of oil are insoluble in water and theref ore f loat. The activities propo sed in this plan will be 

covered by Woodside’s Regional Oil Spill R esponse Plan (refer to infor mation subm itted in 

Appendix G). 

There are no other IPFs (includi ng emissions, physical disturbances to the seafloor, and wastes 

sent to shore for disposal) from the proposed activities which could cause im pacts to water 

quality. 

6. Fisheries 

IPFs that could cause impacts to fisheries as a result of the proposed operations in Walker Ridge 

Block 325 include effluents and accidents. 

Effluents: Effluents such as drillin g fluids and cutting s discharges co ntain com ponents and 

properties which are detrim ental to f ishery resources. Moderate petroleum and m etal 
contamination of sediments and the water column can occur out to several hundred meters downcurrent from the discharge point. Offshore discharges are expected to disperse and dilute to very 

near background levels in the water colum n or on the seafloor within 3,000 m of the discharge 

point, and are expected to have negligible effect on fisheries. 

Accidents: An accidental o il sp ill has th e p otential to cause som e detrim ental effects on 

fisheries; however, it is unlikely that such an event would occur from the proposed activities 

(refer to Item 5 , Water Quality). T he effects of oil on m obile adult finfish or she llfish would 

likely be sublethal and the extent of damage would be reduced to the cap acity of adult fish and 

shellfish to avoid the s pill, to m etabolize hydr ocarbons, and to excrete both m etabolites and 

parent compounds. The activities pr oposed in this plan will be covered by Woodside’s Regional 

OSRP (refer to information submitted in Appendix G). 

There are no IPFs from em issions, physical disturba nces to the seafloor or wastes sent to shore 

for disposal from the proposed activities which could cause impacts to fisheries. 

7. Marine Mammals 

GulfCet II studies revealed that cetaceans of the continental shelf and shelf-edge were alm ost 

exclusively bottlenose dolphin a nd Atlantic spotted dolphin. S quid eaters, including dwarf and 

pygmy killer whale, Risso’s dolphin, rough-toothed dolphin, a nd Cuvier’s beaked whale, 

occurred most frequently along the upper slope in areas outside of anticyclones. IPFs that could 

cause impacts to marine mammals as a result of the proposed operations in W alker Ridge Block 

325 include emissions, effluents, discarded trash and debris, and accidents. 

Emissions: Noises from drilling activ ities, support vessels and helico pters may elicit a startle 

reaction from marine m ammals. This rea ction m ay lead to disruption of m arine m ammals’ 

normal activities. Stress m ay make them more vulnerable to parasites, disease, environm ental 

contaminants, and/or predation (Majors and Myri ck, 1990). There is little conclusive evidence 

for long-term displacements and population trends for marine mammals relative to noise. 

Effluents: Drilling fluids and cuttings discharges contain components which may be detrimental 

to marine mammals. Most operational discharges are diluted and dispersed upon release. Any 

potential impact from drilling fluids would be indirect, either as a result of impacts on prey items 

or possibly through ingestion in the food chain (API, 1989). 

Discarded trash and debris: Both entanglement in, and inge stion of debris have caused the 

death or serious injury of m arine mammals (Laist, 1997; MMC, 1999). The lim ited amount of 

marine debris, if any, resulting from the proposed activities is not expected to substantially harm 

marine mammals. Operators are pro hibited from deliberately discharging debris as mandated by 

MARPOL-Annex V and the Marine Plastic Polluti on Research and Control Act, and regulations 

imposed by various ag encies in cluding the United States Coast Guard (USCG) and the 

Environmental Protection Agency (EPA). 
Woodside will operate in accordance with the regulations an d also avoid accidental loss of solid 

waste items by maintaining waste management plans, manifesting trash sent to shore, and using 

special precautions such as covering outside trash bins to prevent accidental loss of solid waste. 

Special cau tion will be exercised w hen handlin g and disposing of sm all item s and packaging 

materials, particularly those m ade of non-biode gradable, environm entally persistent m aterials 

such as plastic or glass. 

Informational pla cards will be po sted on a ll vessels and f acilities h aving sleeping or f ood 

preparation capabilities. All offshore personne l, including contract ors and other support 

services-related personnel (e.g. helicopter pilots, vessel capt ains and boat crews) will be 

indoctrinated on waste procedures, and will view the video (or Microsoft PowerPoint 

presentation), “Think About It” ( previously “All Washed Up: The Beach Litter Problem”). 

Thereafter, all personnel will view the marine trash and debris training video annually. Offshore 

personnel will also receive an explanation from Woodside m anagement or the d esignated lease 

operator m anagement that em phasizes their commi tment to waste m anagement in acco rdance 

with NTL No. 2007-G03. 

Accidents: Collisions between support vessels and cetaceans would be unusual events, however 

should one occur, death or injury to marine mammals is possible. Contract vessel operators can 

avoid marine mammals and reduce potential deaths by m aintaining a vigilant watch for m arine 

mammals and m aintaining a safe d istance when they are s ighted. Vess el crews sh ould use a 

reference guide to he lp identify the twenty-eigh t species of whales and dolphins, and the single 

species of m anatee that m ay be encountered in the Gulf of Mexico OCS. Vessel crews m ust 

report sightings of any injured or dead protected marine ma mmal species immediately, 

regardless of whether th e injury or death is cau sed by their vessel, to the Marine Mamm al and 

Sea Turtle S tranding Hotline at (888 ) 404-3922, the NMFS Southeast R egional Office at (727 ) 

824-5312, or the Marine Mamm al Stranding N etwork at (305) 862-2850. In addition, if the 

injury or de ath was cau sed by a co llision with a contract v essel, the BOEM m ust be notif ied 

within 24 h ours of the strik e by e mail to protectedspecies@BOEM.gov. If the vessel is the 

responsible party, it is required to remain available to assist th e respective salvage and stranding 

network as needed. 

Oil spills h ave the potentia l to ca use suble thal oil-related injur ies an d spill-re lated deaths to 

marine m ammals. However, it is unlike ly th at an accid ental o il sp ill would occur from the 

proposed activities (refer to Item 5, Water Quality). Oil sp ill response activ ities may increas e 

vessel traffic in th e area, which could add to changes in cetacean behavior and/or distribution, 

thereby causing additional stress to the animals. The effect of oil dispersants on cetaceans is no t 

known. The acute toxicity of oil dispersant chem icals included in W oodside’s OSRP is 

considered to be low when com pared with the constituents and fractions of crude oils and diesel 

products. T he activities proposed in this plan will be covered by Woodside’s OSRP (refer to 

information submitted in accordance with Appendix G). 
There are no other IPF s (including physical di sturbances to the seafloor) from the proposed 

activities which could impact marine mammals. 

8. Sea Turtles 

IPFs that could cause im pacts to sea turtles as a result of the proposed operations include 

emissions, effluents, discarded tr ash and debris, and accidents. Gu lfCet II studies sighted m ost 

loggerhead, Kem p’s ridley and le atherback sea turtles over shel f waters. Historically these 

species have been sighted up to the shelf’s edge. They appear to be more abundant east of the 

Mississippi River than they are west of the river (Fritts et al., 1983b; L ohoefener et al., 1990). 

Deep waters may be used by all species as a transitory habitat. 

Emissions: Noise from drilling activi ties, support vessels, and heli copters may elicit a s tartle 

reaction from sea turtles, but this is a temporary disturbance. 

Effluents: Drilling fluids and cuttings discharges are not known to be lethal to sea turtles. Most 

operational discharges are dilu ted and dispersed upon release. Any potential impact from 

drilling fluids would be indirect , either as a res ult of im pacts on prey item s or possibly through 

ingestion in the food chain (API, 1989). 

Discarded trash and debris: Both entanglement in, and ingestion of, debris have caused the 

death or serious injury of sea turtles (Balazs, 1985). The limited amount of marine debris, if any, 

resulting from the proposed activitie s is not expected to substantially harm sea turtles. Operators 

are prohibited from deliberately discharging de bris as mandated by MARPOL-Annex V and t he 

Marine Plastic Pollution Research and Control Act, and regulations imposed by various agencies 

including th e United States Coast Guard (USC G) and the Environmental Protection Agency 

(EPA). Woodside will operate in accordance with the regulations and also avoid accidental loss 

of solid was te items by m aintaining waste m anagement plans, m anifesting trash sent to shore, 

and using special precautions such as covering outside trash bins to pr event accidental loss of 

solid waste. Special cau tion will be exercised w hen handling and disposing of sm all items and 

packaging m aterials, particularly those m ade of non-biodegradable, environm entally persistent 

materials such as plastic or glass. 

Informational placards will be pos ted on all vessels and facilities h aving sleeping or food 

preparation capabilities. All offshore personne l, including contract ors and other support 

services-related personnel (e.g. helicopter pilots, vessel capt ains and boat crews) will be 

indoctrinated on waste procedures, and will view the video (or Microsoft PowerPoint 

presentation), “Think About It” ( previously “All Washed Up: The Beach Litter Problem”). 

Thereafter, all personnel will view the marine trash and debris training video annually. Offshore 

personnel will also receive an explanation from Woodside m anagement or the d esignated lease 

operator m anagement th at em phasizes th eir co mmitment to waste m anagement in acco rdance 

with NTL No. 2007-G03. 
Accidents: Collisions between support vessels and sea turtles would be unusual events, however 

should one occur, death or injury to sea turtles is possible. Cont ract vessel operators can avoid 

sea turtles and reduce potential deaths by m aintaining a vigilant watch for sea turtles and 

maintaining a safe distance when they are sighte d. Vessel crews should use a reference guide to 

help identify the five species of sea turtles that may be encountered in the Gulf of Mexico OCS. 

Vessel crews m ust report sightings of any inju red or dead protecte d se a tu rtle spec ies 

immediately, regardless of whethe r the injury or death is caused by their vessel, to the Ma rine 

Mammal and Sea Turtle Stranding Hotline at (888) 404-3 922, the NMFS Southeast Region al 

Office at (727) 824-5312, or th e Marine Mamm al Stranding Ne twork at (305) 862-2850. In 

addition, if the injury o r death was caused by a collision with a contract vessel, the BOEM must 

be notified within 24 hours of the strike by email to protectedspecies@BOEM.gov. If the vessel 

is the respo nsible pa rty, it is requ ired to rem ain availab le to assis t the respective salvage and 

stranding network as needed. 

All sea turtle species and their life stages are vulnerab le to the harm ful e ffects of oil through 

direct contact or by fouling of their food. Exposure to oil can be fa tal, particularly to juveniles 

and hatchlings. However, it is unlikely that an accidental oil spill would occur from the proposed 

activities (refer to Item 5, Water Quality). Oil spill response activities may increase vessel traffic 

in the area, which cou ld add to the possib ility of collisions with s ea tur tles. T he activitie s 

proposed in this plan will be covered by W oodside’s Regional Oil Spill Response Plan (refer to 

information submitted in accordance with Appendix G). 

There are no other IPF s (including physical di sturbances to the seafloor) from the proposed 

activities which could impact sea turtles. 

9. Air Quality 

The projected air em issions id entified in Appe ndix G are not expected to affect the OCS air 

quality primarily due to distance to the shore or to any Prevention of Significant Deterioration 

Class I air quality area such as the Breton W ilderness Area. Walker Ridge Block 325 is beyond 

the 200 kilom eter (124 m ile) buffer for the Bret on Wilderness Area and is 155 m iles from the 

coastline. Therefore, n o special mitig ation, monitoring, o r reporting requirem ents apply with 

respect to air emissions. 

Accidents and blowouts can rel ease hydrocarbons or chemicals, which could cause the em ission 

of air po llutants. However, these releases would not im pact onshore air quality because of the 

prevailing atmospheric conditions, em ission height, emission rates, and th e distance of W alker 

Ridge Block 325 from the coastline. There ar e no other IPFs (including effluents, physical 

disturbances to the seafloor, wa stes sent to shore for treatm ent or disposal) from the proposed 

activities which could impact air quality. 

10. Shipwreck Sites (known or potential) 

Potential IPFs that could im pact known or unknown shipwreck sites as a re sult of the proposed 

operations in Walker Ridge Block 325 include disturbances to the seafloor. 
Physical disturbances to the seafloor: A dy namically p ositioned se mi-submersible is being 

used for the proposed activ ities; therefore, only an insignificant am ount of seafloor will be 

disturbed. Because ph ysical distu rbances to the seafloor will be m inimized by the use of a 

dynamically positioned sem i-submersible, W oodside’s proposed operations in W alker Ridge 

Block 325 would not cause impacts to shipwreck sites. 

Additionally, Walker Ridge Block 325 is not located in or adjacen t to an OCS block designated 

by BOEM as having a high probability for occu rrence o f shipwreck s, therefore, no adverse 

impacts are expected. 

Woodside will perform an ROV survey imaging 100% of the seafloor with sector scanning sonar 

within a minimum 500’ radius of the proposed well location(s) prior to or upon commence ment 

of operations. These location s will be certif ied by an authorized m arine archaeologist and b y 

Woodside to be clear of seafloor archaeological resources, including historic shipwrecks. Copies 

of the certifications and a circle radius plat of the survey area will be submitted to the BOEMRE. 

Should a resource be encountere d, Woodside will contact the BO EMRE immediately and make 

every reasonable effort to preserve and protect that cultural resource. . 

There are no other IPF s (includi ng em issions, effluents, wastes sent to shore for treatm ent or 

disposal, or accidents) from the proposed activities which could impact shipwreck sites. 

11. Prehistoric Archaeological Sites 

Potential IP Fs that could cause im pacts to p rehistoric archaeological site s as a r esult of the 

proposed operations in Walker Ridge Block 325 include disturbances to the seafloor.. 

Physical disturbances to the seafloor: A dy namically p ositioned se mi-submersible is being 

used for the proposed activ ities; therefore, only an insignificant am ount of seafloor will be 

disturbed. Because ph ysical distu rbances to the seafloor will be m inimized by the use of a 

dynamically positioned sem i-submersible, W oodside’s proposed operations in W alker Ridge 

Block 325 would not cause impacts to prehistoric archeological sites. 

Additionally, W alker Ridge Bloc k 325 is located outside the Archaeological Prehistoric high 

probability line, therefore, no adverse impacts are expected. 

Woodside will perform an ROV survey imaging 100% of the seafloor with sector scanning sonar 

within a minimum 500’ radius of the proposed well location(s) prior to or upon commence ment 

of operations. These location s will be certif ied by an authorized m arine archaeologist and b y 

Woodside to be clear of seafloor archaeological resources, including historic shipwrecks. Copies 

of the certifications and a circle radius plat of the survey area will be submitted to the BOEMRE. 

Should a resource be encountere d, Woodside will contact the BO EMRE immediately and make 

every reasonable effort to preserve and protect that cultural resource. . 
There are no other IPF s (includi ng em issions, effluents, wastes sent to shore for treatm ent or 

disposal, or accidents) from the proposed activities which could impact prehistoric archeological 

sites. 

Vicinity of Offshore Location 

1. Essential Fish Habitat (EFH) 

IPFs that could cause impacts to EFH as a result of the proposed operations in Walker Ridge 

Block 325 include effluents and accidents. EFH includes all estuarine and m arine waters and 

substrates in the Gulf of Mexico. 

Effluents: The Live Bottom Low Relief Stipula tion, the Live Bottom (Pi nnacle Trend) 

Stipulation, and the Eastern Gulf Pinnacle Trend Stipulation would prevent most of the potential 

impacts on live -bottom comm unities and EFH f rom operationa l waste disch arges. Levels of 

contaminants in drillin g m uds and cutting s a nd produced-water discha rges, d ischarge-rate 

restrictions, and m onitoring a nd toxicity testing are regu lated by th e EPA NPDES perm it, 

thereby eliminating many significant biological or ecol ogical effects. Operational discharges are 

not expected to cause significant adverse impacts to EFH. 

Accidents: An accid ental oil spill has the potential to cause some detrimental effects on EFH. 

Oil spills th at contact coastal bays and estuar ies, as well as OCS waters when pelagic eggs an d 

larvae are p resent, have the g reatest potential to affect fisheries. However, it is unlikely that an 

oil spill would occur from the proposed activities (refer to Item 5, Water Quality). The activities 

proposed in this plan will be cov ered by W oodside’s Regional OSRP (refer to inform ation 

submitted in Appendix G). 

There are no other IPFs (includi ng emissions, physical disturbances to the seafloor and wastes 

sent to shore for treatment or disposal) from the proposed activities which could impact essential 

fish habitat. 

2. Marine and Pelagic Birds 

IPFs that could im pact marine birds as a result of the proposed activities include air emissions, 

accidental oil spills, and discarded trash and debris from vessels and the facilities. 

Emissions: Em issions of pollutants into the a tmosphere from these activ ities ar e f ar below 

concentrations which could harm coastal and marine birds. 

Accidents: An oil spill woul d cause localized, low-level petroleum hydrocarbon contamination. 

However, it is unlikely that an oil spill would occur from the proposed activities (refer to Item 5, 

Water Quality). Marine and pelagic birds feedi ng at the spill loca tion may experience chronic, 

nonfatal, physiological stress. It is expected th at few, if any, coastal and m arine birds would 
actually be af fected to that exten t. The activ ities propo sed in th is plan will b e covered by 

Woodside’s Regional OSRP (refer to information submitted in Appendix G). 

Discarded trash and debris : Marine and pelagic birds could become entangled and snared i n 

discarded trash and debris, or ingest small plastic debris, which can cause permanent injuries and 

death. Operators are prohibited from deliberately discharging debris as mandated by MARPOLAnnex V and the Marine Plastic Pollution Research and Control Act, and regulations imposed by 

various ag encies in cluding the United States Coast Guard (USCG) and the Environm ental 

Protection Agency (EP A). W oodside will op erate in accordance with the regu lations and also 

avoid accidental loss of solid waste items by maintaining waste management plans, manifesting 

trash sent to shore, and using special precau tions such as co vering outside trash b ins to preven t 

accidental loss of solid waste. Special caution w ill be exercised when handling and d isposing of 

small items and packaging m aterials, par ticularly those m ade of non-biodegradable, 

environmentally pe rsistent m aterials such as plastic or gla ss. Inf ormational plac ards will b e 

posted on all vessels an d facilities having sleeping or food preparation capabilities. All offshore 

personnel, including contractors and other suppor t services-related pers onnel (e.g. helicopter 

pilots, vessel captains and boat cr ews) will be indoctrinated on wa ste procedures, and will view 

the video (or Microsoft PowerPoint presentation), “Think About It” ( previously “All Washed 

Up: The Beach Litter Problem”). Thereafter, all personnel will view th e marine trash and debris 

training vid eo annually. Offshore personnel w ill also receive an explanation fro m Woodside 

management or the designated lease operator m anagement that emphasizes their commitment to 

waste management in accordance with NTL No. 2007-G03. Debris, if any, from these proposed 

activities will s eldom intera ct with m arine an d pelagic b irds; th erefore, th e effects will b e 

negligible. 

There are no other IPFs (including effluents, physical disturbances to the seafloor, or wastes sent 

to shore for treatm ent or disposal) from the pr oposed activities which could im pact marine and 

pelagic birds. 

3. Public Health and Safety Due to Accidents. 

There are no IPFs (em issions, effluents, physical disturbances to the seafloor, wastes sent to 

shore for treatm ent or disposal o r acciden ts, including an acciden tal H 2S release ) f rom the 

proposed activities which could cau se impacts to public health a nd safety. In accordance with 

NTL No.’s 2008-G04, 2009-G27, and 2009-G31, suffi cient information is included in Appendix 

C to justify our request that our proposed activities be classified by BOEM as H2S absent. 

Coastal and Onshore 

1. Beaches 

IPFs from t he proposed activities that could cause im pacts to beaches include accidents (oil 

spills) and discarded trash and debris. 
Accidents: Oil spills co ntacting beaches would have impacts on the use of recreation al beaches 

and associated resources. Due t o the dist ance from s hore (155 m iles) and the response 

capabilities that would be im plemented, no si gnificant ad verse im pacts are exp ected. The 

activities proposed in this plan will be c overed by W oodside’s Regional OSRP (refer to 

information submitted in Appendix G). 

Discarded trash and debris: T rash on the beach is recogni zed as a m ajor th reat to the 

enjoyment and use of b eaches. Th ere will on ly be a lim ited amount of m arine debris, if any , 

resulting from the proposed activ ities. Operators are prohibite d from deliberately discharging 

debris as m andated by MARPOL- Annex V a nd th e Marine Plas tic Pollution Research and 

Control Act, and regulations im posed by variou s agencies includ ing the United State s Coas t 

Guard (USCG) and th e Environm ental Protecti on Agency (EPA). Woodside will op erate in 

accordance with the regulations and also avoi d acciden tal los s of solid waste item s by 

maintaining waste m anagement plans, m anifesting trash sent to shore, and using special 

precautions such as covering outs ide trash bins to prevent accidental loss of solid waste. Special 

caution will be exercised when handling and dispos ing of sm all items and packaging m aterials, 

particularly those m ade of non- biodegradable, environm entally pe rsistent m aterials such as 

plastic or glass. 

Informational placards will be pos ted on all vessels and facilities h aving sleeping or food 

preparation capabilities. All offshore personne l, including contract ors and other support 

services-related personnel (e.g. helicopter pilots, vessel capt ains and boat crews) will be 

indoctrinated on waste procedures, and will view the video (or Microsoft PowerPoint 

presentation), “Think About It” ( previously “All Washed Up: The Beach Litter Problem”). 

Thereafter, all personnel will view the marine trash and debris training video annually. Offshore 

personnel will also receive an explanation from Woodside m anagement or the d esignated lease 

operator m anagement th at em phasizes th eir co mmitment to waste m anagement in acco rdance 

with NTL No. 2007-G03. 

There are no other IPF s (em issions, effluents, physical disturbances to the seaflo or, or wastes 

sent to shore for treatment or disposal) from the proposed activities which could impact beaches. 

2. Wetlands 

IPFs from t he proposed activities that could ca use im pacts to wetlands include accidents (oil 

spills) and discarded trash and debr is. However, it is un likely that an oil spill would occur from 

the proposed activities (refer to Item 5 , W ater Quality ). Due to the distance f rom shore (155 

miles) and the response capabilities that woul d be im plemented, no im pacts are expected. The 

activities proposed in this plan will be c overed by W oodside’s Regional OSRP (refer to 

information submitted in Appendix G). 

Accidents: Oil spills contacting wetlands would have impacts on the salt m arshes and seagrass 

beds tha t f ringe the co astal are as of the Gulf of Mexico. Due to the distance from shore 

(155miles) and the response capab ilities that would be im plemented, no significant adverse 
impacts are expected. The activ ities propos ed in this plan will be covered by Woodside’s 

Regional OSRP (refer to information submitted in Appendix G). 

Discarded trash and debris: There will only be a lim ited a mount of m arine debris, if any, 

resulting from the proposed activ ities. Operators are prohibite d from deliberately discharging 

debris as m andated by MARPOL- Annex V a nd th e Marine Plas tic Pollution Research and 

Control Act, and regulations im posed by variou s agencies includ ing the United States Coas t 

Guard (USCG) and th e Environm ental Protecti on Agency (EPA). Woodside will op erate in 

accordance with the regulations and also avoi d acciden tal los s of solid waste item s by 

maintaining waste m anagement plans, m anifesting trash sent to shore, and using special 

precautions such as covering outs ide trash bins to prevent accidental loss of solid waste. Special 

caution will be exercised when handling and dispos ing of sm all items and packaging m aterials, 

particularly those m ade of non- biodegradable, environm entally pe rsistent m aterials such as 

plastic or glass. 

Informational placards will be pos ted on all vessels and facilities h aving sleeping or food 

preparation capabilities. All offshore personne l, including contract ors and other support 

services-related personnel (e.g. helicopter pilots, vessel capt ains and boat crews) will be 

indoctrinated on waste procedures, and will view the video (or Microsoft PowerPoint 

presentation), “Think About It” ( previously “All Washed Up: The Beach Litter Problem”). 

Thereafter, all personnel will view the marine trash and debris training video annually. Offshore 

personnel will also receive an explanation from Woodside m anagement or the d esignated lease 

operator m anagement th at em phasizes th eir co mmitment to waste m anagement in acco rdance 

with NTL No. 2007-G03. 

There are no other IPF s (em issions, effluents, physical disturbances to the seaflo or, or wastes 

sent to shore for treatm ent or disposal) fr om the proposed activities which could im pact 

wetlands. 

3. Shore Birds and Coastal Nesting Birds 

Potential IPFs from the proposed activities that could cause im pacts to shore birds and coastal 

nesting birds include accidents (oil spills) and discarded trash and debris. 

Accidents: Oil spills could cause impacts to shore birds and coastal nesting birds. However, it is 

unlikely that an oil spill would occur from the proposed activities (refer to Item 5 , W ater 

Quality). Given the distance from shore (155 miles ) and the response capabilities th at would be 

implemented, no significant adverse im pacts are expected. The activities proposed in this plan 

will be covered by Woodside’s Regional OSRP (refer to information submitted in Appendix G). 

Discarded trash and debris: Coastal and m arine birds are highly susceptible to entanglem ent 

in floating, submerged, and beached marine debris: specifically plastics. Operators are prohibited 

from deliberately discharging debris as m andated by MARPOL-Annex V and the Marine Plastic 
Pollution Research and Control Ac t, and regulations im posed by va rious agencies in cluding the 

United States Coast Guard (USCG) and the Environmental Protection Agency (EPA). Woodside 

will op erate in acco rdance with th e regu lations a nd also avoid a ccidental los s of solid waste 

items by maintaining waste management plans, manifesting trash sent to shore, and using special 

precautions such as covering outside trash bins to prevent accidental loss of solid waste. Special 

caution will be exercised when handling and dispos ing of sm all items and packaging m aterials, 

particularly those m ade of non- biodegradable, environm entally pe rsistent m aterials such as 

plastic or glass. 

 

Informational pla cards will be pos ted on vesse ls and eve ry f acility th at has sleeping or f ood 

preparation capabilities. All offshore personne l, including contract ors and other support 

services-related personnel (e.g. helicopter pilots, vessel capt ains and boat crews) will be 

indoctrinated on waste procedures, and will view the video (or Microsoft PowerPoint 

presentation), “Think About It” ( previously “All Washed Up: The Beach Litter Problem”). 

Thereafter, all personnel will view the marine trash and debris training video annually. Offshore 

personnel will also receive an explanation from Woodside m anagement or the d esignated lease 

operator m anagement that em phasizes their commi tment to waste m anagement in acco rdance 

with NTL No. 2007-G03. 

There are no other IPF s (em issions, effluents, physical disturbances to the seaflo or, or wastes 

sent to shore for treatm ent or disposal) from the proposed activities that could cause im pacts to 

shore birds and coastal nesting birds. 

4. Coastal Wildlife Refuges 

Potential IPFs from the proposed activities that could cause im pacts to coastal wildlife refuges 

include accidents (oil spills) and discarded trash and debris. 

Accidents: An acciden tal oil spill from the proposed activities could cause im pacts to co astal 

wildlife refuges. However, it is unlikely that an oil spill would occur from the proposed activities 

(refer to Item 5, Water Quality). Due to th e distance from shore (155 m iles) and the response 

capabilities that would be im plemented, no sign ificant adv erse im pacts are expec ted. The 

activities proposed in this plan will be c overed by W oodside’s Regional OSRP (refer to 

information submitted in Appendix G). 

Discarded trash and debris: Entanglement in floating, submerged, and beached marine debris: 

specifically plastics could impact inhabitants of coastal wildlife refuges. Operators are prohibited 

from deliberately discharging debris as m andated by MARPOL-Annex V and the Marine Plastic 

Pollution Research and Control Ac t, and regulations im posed by va rious agencies including the 

United States Coast Guard (USCG) and the Environmental Protection Agency (EPA). Woodside 

will op erate in acco rdance with th e regu lations a nd also avoid a ccidental los s of solid waste 

items by maintaining waste management plans, manifesting trash sent to shore, and using special 

precautions such as covering outside trash bins to prevent accidental loss of solid waste. Special 

caution will be exercised when handling and dispos ing of sm all items and packaging m aterials, 
particularly those m ade of non- biodegradable, environm entally pe rsistent m aterials such as 

plastic or glass. 

 

Informational plac ards will be posted on vesse ls and ever y f acility th at has sle eping or f ood 

preparation capabilities. All offshore personne l, including contract ors and other support 

services-related personnel (e.g. helicopter pilots, vessel capt ains and boat crews) will be 

indoctrinated on waste procedures, and will view the video (or Microsoft PowerPoint 

presentation), “Think About It” ( previously “All Washed Up: The Beach Litter Problem”). 

Thereafter, all personnel will view the marine trash and debris training video annually. Offshore 

personnel will also receive an explanation from Woodside m anagement or the d esignated lease 

operator m anagement that em phasizes their commi tment to waste m anagement in acco rdance 

with NTL No. 2007-G03. 

There are no other IPF s (em issions, effluents, physical disturbances to the seaflo or, or wastes 

sent to shore for treatm ent or disposal) from the proposed activities that could cause im pacts to 

coastal wildlife refuges. 

5. Wilderness Areas 

Potential IPFs from the proposed activities that could cause im pacts to wilderness areas include 

accidents (oil spills) and discarded trash and debris. 

An accidental oil spill from the proposed activiti es could cause im pacts to wilderness areas. 

However, it is unlikely that an oil spill would occur from the proposed activities (refer to Item 5, 

Water Quality). Due to the distance from the nearest designated wild erness area (> 100 m iles) 

and the response capabili ties that would be implem ented, no significant adverse im pacts are 

expected. T he activities proposed in this plan will b e covered by Woodside’s Regional OSRP 

(refer to information submitted in Appendix G).

Discarded trash and debris: Entanglement in floating, submerged, and beached marine debris: 

specifically plastics could im pact inhabitants of wilderness areas. Operators are proh ibited from 

deliberately discharging debr is as m andated by MARPOL-Annex V and the Marine Plastic 

Pollution Research and Control Ac t, and regulations im posed by va rious agencies including the 

United States Coast Guard (USCG) and the Environmental Protection Agency (EPA). Woodside 

will op erate in acco rdance with th e regu lations a nd also avoid a ccidental los s of solid waste 

items by maintaining waste management plans, manifesting trash sent to shore, and using special 

precautions such as covering outside trash bins to prevent accidental loss of solid waste. Special 

caution will be exercised when handling and dispos ing of sm all items and packaging m aterials, 

particularly those m ade of non- biodegradable, environm entally pe rsistent m aterials such as 

plastic or glass. 

 

Informational plac ards will be posted on vesse ls and ever y f acility th at has sle eping or f ood 

preparation capabilities. All offshore personne l, including contract ors and other support 

services-related personnel (e.g. helicopter pilots, vessel capt ains and boat crews) will be 

indoctrinated on waste procedures, and will view the video (or Microsoft PowerPoint 
presentation), “Think About It” ( previously “All Washed Up: The Beach Litter Problem”). 

Thereafter, all personnel will view the marine trash and debris training video annually. Offshore 

personnel will also receive an explanation from Woodside m anagement or the d esignated lease 

operator m anagement that em phasizes their commi tment to waste m anagement in acco rdance 

with NTL No. 2007-G03. 

There are no other IPF s (em issions, effluents, physical disturbances to the seaflo or, or wastes 

sent to shore for treatm ent or disposal) from the proposed activities that could cause im pacts to 

wilderness areas. 

6. Other Environmental Resources Identified 

(C) Impacts on your proposed activities 

The site–specific environm ental conditions have been taken into account for the proposed 

activities. No i mpacts are expected on the propos ed activities from site-specific environm ental 

conditions. 

(D) Environmental Hazards 

During the hurricane season, June through Novem ber, the Gulf of Mexico is im pacted by an 

average of ten tropical storm s (39-73 mph winds), of which si x become hurricanes ( > 74 m ph 

winds). Due to its location in the gulf, W alker Ridge Block 325 may experience hurricane and 

tropical storm force wi nds, and related sea curr ents. Thes e factors can adverse ly impact the 

integrity of the operations covered by this plan. A significant storm may present physical hazards 

to operators and vessels, damage exploration or production equipment, or result in the release of 

hazardous materials (including hydrocarbons). Additionally, the displacement of equipment may 

disrupt the local benthic habitat and pose a threat to local species. 

The following preventative measures included in this plan may be implemented to mitigate these 

impacts: 

1. Drilling 

a. Secure well 

b. Secure rig / platform 

c. Evacuate personnel 

Drilling activities will be conducted in accordance with NTL No.’s 2008-G09, 2009-G10, and 

2010-N10. 

2. Structure Installation 

 Operator will not conduct structure installation operations during Tropical Storm or 

 Hurrican e threat. 
(E) Alternatives 

No alternatives to the proposed activities were considered to reduce environmental impacts. 

(F) Mitigation Measures 

No m itigation m easures other than those requ ired by regu lation will be em ployed to avoid, 

diminish, or eliminate potential impacts on environmental resources. 

(G) Consultation 

No agencies or persons were consulted regard ing potential impacts associ ated with the proposed 

activities. Therefore, a list of such entities has not been provided. 

(H) Preparer(s) 

Matt Harlan 

J. Connor Consulting, Inc. 

16225 Park Ten Place, Suite 700 

Houston, TX 77084 

(281) 578-3388 

matt.harlan@jccteam.com 

(I) References 

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water m arine m ammals: a literature revi ew. W ashington, DC: Am erican Petroleum 

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Balazs, G.H. 1985. I mpact of ocean debris on m arine turtles: entang lement and ingestion. In : 

Shomura, R.S. and H.O. Yoshida, eds. Proceed ings, W orkshop on the Fate and Im pact of 

Marine Debris, 26-29 Nove mber 1984, Hono lulu, HI. U.S. Dept. of Co mmerce. NOAA 

Tech. Memo. NOAA-TM-NMFS-SWFC-54. Pp 387-429. 

Burke, C.J. and J.A. Veil. 1995. Potential benef its from regulatory cons ideration of synthetic 

drilling m uds. Environm ental Assessm ent Division, Argonne Na tional Laboratory, 

ANL/EAD/TM-43 

Daly, J.M. 1997. Controlling the discharge of synthetic-based drilling fluid contam inated 

cuttings in waters of th e United States. U. S. Environm ental Protection Agency, Office of 

Water. Work Plan, June 24, 1997. 

Hansen, D.J. 198l. The relative sensitivity of seabird populations in Alaska to oil pollution. U.S. 

Dept. of the Interior, Bureau of Land Mana gement, Alaska OCS Region, Anchorage. BLMYK-ES-81-006-1792. 
Laist, D.W . 1997. Im pacts of m arine debris: en tanglement of m arine life in m arine debris 

including a comprehensive list of species with entanglement and ingestion records. In: Coe, 

J.M. and D.B. Rogers, eds. Marine debris: s ources, impacts, and solutions. New York, NY: 

Springer-Verlag. Pp. 99-139 

Majors, A.P. and A.C. Myrick, Jr. 1990. Effects of noise on animals: implications for dolphins 

exposed to seal bom bs in the eastern tropi cal Pacific purse-sein e fishery–an annotated 

bibliography. NOAA Administrative Report LJ-90-06. 

Marine Mammal Commission. 1999. Annual report to Congress – 1998 

Piatt, J.F., C.J. Lensink, W . Butler, M. Ke ndziorek, and D.R. Nysewander. 1990. Imm ediate 

impact of the Exxon Valdez oil spill on marine birds. The Auk. 107 (2): 387-397 

Vauk , G., E. Hartwig, B. Reineking, and E. Vauk-Hentzelt. 1989. L osses of seabirds by oil 

pollution at the German North Sea coast. Topics in Marine Biology. Ros, J.D, ed. Scient. 

Mar. 53 (2-3): 749-754 

Vermeer, K. and R. Vermeer, 1975 Oil threat to birds on the Canadian west coast. The Canadian 

Field-Naturalist. 89:278-298. 

Although not cited, the following were utilized in preparing this EIA: 

• Hazard Surveys 

• BOEM EIS’s: 

o GOM Deepwater Operations and Activities. Environm ental Assessm ent. BOEM 2000-

001 

o GOM Central and W estern Planning Areas Sales 166 and 168 Final Environm ental 

Impact Statement. BOEM 96-0058