De Soto Canyon Block 178 

Environmental Impact Analysis for Initial Exploration Plan 

Figure 1. Location of De Soto Canyon Block 178. 
Coastal Zone Management Consistency Statements 

for the States of Louisiana, Florida & Alabama 

Attachment Q 

(Public Information) 



Coastal Zone Management Consistency Enforceable 

Policies for the States of Florida & Alabama 

Attachment R 

(Public Information) 
De Soto Canyon Block 178 – Initial Exploration Plan Page 1 

Murphy Exploration & Production Company - USA 

COASTAL ZONE MANAGEMENT 

 

STATE OF FLORIDA ENFORCEABLE POLICIES 

Murphy Exploration & Production Company - USA 

Initial Exploration Plan 

Lease OCS-G 25850 

De Soto Canyon Block 178 

“Titan Prospect” 
De Soto Canyon Block 178 – Initial Exploration Plan Page 2 

Murphy Exploration & Production Company - USA 

STATE OF FLORIDA 

COASTAL ZONE CONSISTENCY POLICIES 

Chapter 161 – Beach and Shore Preservation 

The coastal waters of the State of Florida are considered among the most valuable natural, 

aesthetic, and economic resources and that they protect and provide habitat for a variety of 

plant and animal life. 

The State is required to protect beach and dune systems from imprudent activities that could 

weaken, damage, or destroy the integrity of the system. The coastal sediments must also be 

managed to reduce erosion; and the critically eroding beaches must be maintained and/or 

restored. The State also designates coastal areas used, or likely to be used, by sea turtles for 

nesting, and prohibits the removal of vegetable cover that binds sand. 

The offshore activities to be conducted in De Soto Canyon Block 178 are located 

approximately 107 miles from the nearest State of Florida coastal shoreline; whereas the 

onshore support operations will be conducted from an existing infrastructure located in 

Fourchon, Louisiana. Murphy Exploration & Production Company - USA (Murphy) does 

not anticipate the need for expansion of this existing infrastructure since the proposed 

activities are temporary in nature. If productive results are obtained, a Development and 

Production Plan would be prepared, and such a need for new and/or expansion of an 

onshore infrastructure will be reviewed. 

The onshore support and offshore activities should not have an impact on the coastal areas 

of the State of Florida. The transportation modes from the onshore support base in 

Fourchon, Louisiana to De Soto Canyon Block 178 will be in excess of 145 miles from the 

coastal shoreline in Louisiana and 107 miles from the coastal shoreline in Florida. In the 

event of an unanticipated blowout resulting in an oil spill, it is unlikely to have an impact 

based on the industry wide standards for using proven equipment and technology for such 

responses, implementation of our Sub-Regional Oil Spill Response Plan which address 

available equipment and personnel, techniques for containment and recovery, and removal 

of the oil spill. 

The precautions addressed in Murphy’s standard safety and environmental operating 

procedures and our Sub-Regional Oil Spill Response Plan are considered consistent with the 

State of Florida policies for protecting beach and shore preservation. 

Chapter 252 – Emergency Management 

The State is directed to reduce the vulnerability of its people and property to natural and 

manmade disasters; prepare for, respond to, and reduce the impacts of natural and manmade 

disasters; and decrease the time and resources needed to recover from disasters. 

Disaster mitigation is necessary to ensure the common defense of Floridians’ lives and to 

protect the public peace, health and safety. The policies in this chapter provide the means to 
De Soto Canyon Block 178 – Initial Exploration Plan Page 3 

Murphy Exploration & Production Company - USA 

assist in the prevention or mitigation of emergencies that may be caused or aggravated by the 

inadequate planning or regulation of facilities and land uses. State agencies are directed to 

keep land uses and facility construction under continuing study and identify areas that are 

particularly susceptible to natural or manmade catastrophic occurrences. 

The proposed activities do not involve any new construction or operations of any facilities 

within the State of Florida. 

In the event of an unanticipated blowout resulting in an oil spill, it is unlikely to have an 

impact based on the industry wide standards for using proven equipment and technology for 

such responses, implementation of our Sub-Regional Oil Spill Response Plan which address 

available equipment and personnel, techniques for containment and recovery, and removal 

of the oil spill. 

The precautions addressed in Murphy’s standard safety and environmental operating 

procedures and our Sub-Regional Oil Spill Response Plan are considered consistent with the 

State of Florida policies on preparing for and responding to emergency management for the 

people and resources of the state. 

Chapter 253 – State Lands 

This chapter defines the state-owned and state-managed lands and grants authority to 

acquire and lease lands, and to grant rights-of-ways and easements. The enforceable policies 

guide the management of state-owned and sovereign submerged lands and property by the 

Board of Trustees of the Internal Improvement Trust Fund (Trustees). Lands acquired for 

preservation, conservation, and recreation serve the public interest by contributing to the 

public health, welfare, and economy. In carrying out the requirements of this statue, the 

Trustees are directed to take necessary action to fully conserve and protect state lands, 

maintain natural conditions, protect and enhance natural areas and ecosystems, prevent 

damage and depredation, and preserve archaeological and historical resources. All 

submerged lands are considered single-use lands to be maintained in natural condition for 

the propagation of fish and wildlife and public recreation. Where multiple uses are 

permitted, ecosystem integrity, recreational benefits, and wildlife values are conserved and 

protected. 

In order to conduct the proposed offshore activities in De Soto Canyon Block 178 and 

onshore support activities in Fourchon, Louisiana; Murphy does not anticipate the need to 

acquire any rights-of-way and/or easements across Florida state-owned lands. The support 

related activities will take the most direct route from Fourchon, Louisiana; thereby avoiding 

any usage of the state-owned lands. 

In the event of an unanticipated blowout resulting in an oil spill, it is unlikely to have an 

impact based on the industry wide standards for using proven equipment and technology for 

such responses, implementation of our Sub-Regional Oil Spill Response Plan which address 

available equipment and personnel, techniques for containment and recovery, and removal 

of the oil spill. 
De Soto Canyon Block 178 – Initial Exploration Plan Page 4 

Murphy Exploration & Production Company - USA 

The precautions addressed in Murphy’s standard safety and environmental operating 

procedures and our Sub-Regional Oil Spill Response Plan are considered consistent with the 

State of Florida policies on protection of state-owned lands. 

Chapter 258 – State Parks and Preserves 

State parks and preserves are acquired to exemplify the state’s natural values and to ensure 

that these values are conserved for all time. Parks and preserves are managed for the nondepleting use, enjoyment, and benefit of Floridians and visitors, and to contribute to the 

State’s tourist appeal. Aquatic preserves are recognized as having exceptions biological, 

aesthetic, and scientific value and are set aside for the benefit of future generations. 

Disruptive physical activities and polluting discharges are highly restricted in aquatic 

preserves. State managed wildlife, and scenic rivers possess exceptionally remarkable and 

unique ecological, fish and wildlife, and recreational values, and are designated for 

permanent preservation and enhancement for both the present and future. 

This chapter specifies limitations on dredge-and-fill operations, overboard discharges, 

erection of structures, and drilling activities for oil and gas within aquatic preserves. 

The proposed activities will take place in water depths in excess of 6500 feet, and will not 

involve any dredge-and-fill operations. Only authorized effluents will be discharged 

overboard, as regulated by Region IV of the EPA; subject to certain limitations, prohibitions 

and recordkeeping. Such discharges will occur at a distance in excess of 107 miles from the 

coastal inland area and should not impact the state parks, preserves and/or recreational 

areas. In the event of an unanticipated blowout resulting in an oil spill, it is unlikely to have 

an impact based on the industry wide standards for using proven equipment and technology 

for such responses, implementation of our Sub-Regional Oil Spill Response Plan which 

address available equipment and personnel, techniques for containment and recovery, and 

removal of the oil spill. 

The precautions addressed in Murphy’s standard safety and environmental operating 

procedures and our Sub-Regional Oil Spill Response Plan are considered consistent with the 

State of Florida policies on preserving and protecting state parks and preserves. 

Chapter 259 – Land Acquisitions for Conservation or Recreation 

This chapter discusses the “Land Conservation Act” and the acquisition of lands or water 

areas for preservation, conservation, and recreational purposes. The chapter also indicates 

an area is of special importance to the State if it involves an endangered or natural resource 

in imminent danger of development, is of unique value to the State, will result in irreparable 

loss to the State, or will impair the State’s ability to manage or protect other state-owned 

lands. The policies guide the acquisition and management of lands to conserve and maintain 

the State’s unique natural resources, protect environmental quality, and provide recreation 

opportunities for the benefit of future generations. Florida’s legislature and citizens have 

made a tremendous financial commitment to long-term land acquisitions that will preserve 

and restore unique ecosystems, habitats, water resources, and recreational lands. 
De Soto Canyon Block 178 – Initial Exploration Plan Page 5 

Murphy Exploration & Production Company - USA 

Murphy will be using the existing onshore support infrastructure located in Fourchon, 

Louisiana; and as such does not anticipate a need for new development, construction, 

dredging or filling activities on Florida’s lands or waters. All discharges associated with the 

proposed activities will be regulated by both the Bureau of Ocean Energy 

Managements/Bureau of Safety and Environmental Enforcement and the U.S. 

Environmental Protection Agency for projected air emissions and overboard discharges 

associated with the proposed activities. Such releases and discharges will occur in excess of 

94 miles from the nearest Florida shoreline, and will not have any impact on Florida lands 

being acquired or managed for preservation, conservation, or recreational purposes. 

In the event of an unanticipated blowout resulting in an oil spill, it is unlikely to have an 

impact based on the industry wide standards for using proven equipment and technology for 

such responses, implementation of our Sub-Regional Oil Spill Response Plan which address 

available equipment and personnel, techniques for containment and recovery, and removal 

of the oil spill. 

The precautions addressed in Murphy’s standard safety and environmental operating 

procedures and our Sub-Regional Oil Spill Response Plan are considered consistent with the 

state’s enforceable policies of lands to conserve and maintain the State’s unique natural 

resources, protection of environmental quality, and providing recreational opportunities. 

Chapter 260 – Recreational Trails System 

This chapter discusses the “Florida Greenways and Trails Act” and the State policies to 

conserve, develop and use its natural resources for healthful and recreational purposes by the 

establishment of a “Florida Greenways and Trails System”. This System serves to provide 

recreational opportunities, including canoeing, jogging, and historical and archaeological 

interpretation, by acquiring designated lands and waterways for open space to benefit 

environmentally sensitive lands and wildlife. 

Murphy will be using the existing onshore support infrastructure located in Fourchon, 

Louisiana; and as such does not anticipate a need for new development, construction, 

dredging or filling activities on Florida’s lands or waters. All travel routes to and from the 

onshore support base and the offshore locations in De Soto Canyon Block 178 will avoid 

any recreational trail systems established by the State of Florida. 

Therefore, the activities proposed in the Joint Initial Exploration Plan are consistent with the 

enforceable policies of this chapter. 

Chapter 267 – Archives, History, and Records Management 

This chapter discusses the “Florida Historical Resources Act,” the State policy to locate, 

inventory, and evaluate historical properties, and the preservation by the Division of 

Historical Resources of all historical property, including sunken or abandoned ships with 

intrinsic, historical, or archaeological value. The enforceable policies recognize the State’s 

rich and unique heritage of historic resources and direct the State to locate, acquire, protect, 

preserve, operate, and interpret historic and archaeological resources for the benefit of 
De Soto Canyon Block 178 – Initial Exploration Plan Page 6 

Murphy Exploration & Production Company - USA 

current and future generations of Floridians. Objects or artifacts with intrinsic historic or 

archaeological value located on, or abandoned on, state-owned lands or state-owned 

submerged lands belong to the citizens of the State. The Act operates in conjunction with 

the National Historic Preservation Act of 1966 to require State and Federal agencies to 

consider the effect of their direct or indirect actions on historic and archaeological resources. 

These resources cannot be destroyed or altered unless no prudent alternative exists. 

Unavoidable impacts must be mitigated. 

Murphy contracted Geoscience Earth and Marine Services, Inc. to evaluate 3-D data for the 

purpose of identifying potential shallow hazards associated with the proposed surface 

locations provided in the Initial Exploration Plan. 

De Soto Canyon Block 178 is not located within an area identified by the Bureau of Ocean 

Energy Managements/Bureau of Safety and Environmental Enforcement as having potential 

for historic and/or prehistoric cultural resources. 

The wellsite location clearance assessments, included in the Initial Exploration Plan, confirm 

there are no manmade facilities and seafloor obstructions within the surveyed areas. 

Therefore, the proposed activities should not impact any objects or artifacts with intrinsic 

historic or pre-historic value. However, in the event such objects or artifacts are uncovered 

as a result of the proposed activities, Murphy will cease operations and provide immediate 

notification to the Bureau of Ocean Energy Managements/Bureau of Safety and 

Environmental Enforcement. 

 

Therefore, the activities proposed in the Initial Exploration Plan are consistent with the 

enforceable policies of this chapter. 

Chapter 288 – Commercial Development and Capital Improvements 

This chapter discusses the enforceable policies to promote and develop the general business, 

trade, and tourism components of the State economy. The policies include requirements to 

protect and promote the natural, coastal, historical, and cultural tourism assets of the State; 

foster the development of nature-based tourism and recreation; and upgrade the image of 

Florida as a quality destination. Natural resource-based tourism and recreational activities 

are critical sectors of Florida’s economy. The needs of the environment must be balance 

with the need for growth and economic development. 

As Murphy will be using the existing onshore support infrastructure in Fourchon, Louisiana; 

we do not anticipate the need for activities to be conducted in Florida which would affect 

the general business, trade, or tourism components of the State economy. The most direct 

traffic routes for support vessels from Louisiana to De Soto Canyon Block 178. Therefore, 

no Florida water routes will be utilized. 

The authorized overboard discharges attributable to the proposed activities will be 

temporary in nature, and will be localized in the vicinity of the surface location for each 

proposed well; which should not impact Florida lands or waters. Disposal of trash and 

debris into the receiving waters is strictly prohibited by the Bureau of Ocean Energy 
De Soto Canyon Block 178 – Initial Exploration Plan Page 7 

Murphy Exploration & Production Company - USA 

Managements/Bureau of Safety and Environmental Enforcement, US Environmental 

Protection Agency and the US Coast Guard. In the event of an unanticipated blowout 

resulting in an oil spill, it is unlikely to have an impact based on the industry wide standards 

for using proven equipment and technology for such responses, implementation of our SubRegional Oil Spill Response Plan which address available equipment and personnel, 

techniques for containment and recovery, and removal of the oil spill. 

The precautions addressed in Murphy’s standard safety and environmental operating 

procedures and our Sub-Regional Oil Spill Response Plan are considered consistent with the 

state’s enforceable policies to promote and develop the general business, trade, and tourism 

components of the State’s economy. 

Chapter 370 – Saltwater Fisheries 

This chapter addresses the enforceable policies directed by the State to conserve and manage 

its renewable marine fishery resources through the protection and management of marine 

habitat and saltwater fisheries. The paramount conservation and management objective is 

the continuing health and abundance of the resource. Best available information must be 

used to manage and protect the State’s marine crustacean, shell, and finfish resources and to 

regulate the commercial and recreational use of the State’s saltwater fisheries to ensure 

optimum sustained benefits to the people of the State. 

The authorized effluents to be discharged during the proposed drilling operations may 

temporarily affect water quality in the immediate vicinity of each discharge point associated 

with each well location. Water quality is expected to return to normal in the area following 

the cessation of operations. 

Discharges of water-based drilling muds and cuttings will produce temporary, localized 

increases in suspended solids and barium in the water column around the drilling rig. In 

general, turbid water can be expected to extend between a few hundred meters and several 

kilometers down current from the discharge point. 

During well intervals when synthetic-based mud (SBM) is used, it will not be discharged. 

However, cuttings would be discharged, and they would include some adhering SBM. The 

SBM retention on cuttings will comply with National Pollutant Discharge Elimination 

System (NPDES) permit requirements. After discharges, synthetic mud retained on cuttings 

would be expected to tightly adhere to the cuttings particles and consequently would not 

produce much turbidity as the cuttings sink through the water column. Minimal impacts on 

water quality are anticipated. 

Other minor authorized effluents discharged overboard may include sanitary and domestic 

waste, deck drainage from the dynamically positioned semi-submersible, uncontaminated 

seawater for cooling machinery, and desalination brine. Such discharges may case localized, 

short-term impacts on water quality near the discharge points for each well location. There 

is a very low probability that a diesel spill may occur while conducting transfer operations 

from the supply vessel to the MODU. Murphy’s Sub-Regional Oil Spill Response Plan 

discusses any potential impacts from these types of spills on Florida’s coastal zone. This 
De Soto Canyon Block 178 – Initial Exploration Plan Page 8 

Murphy Exploration & Production Company - USA 

Plan also describes response actions for specific hypothetical spill events, provisions and 

approvals required for the use of dispersants by boat or aerial application, provisions for 

inspection and maintenance of response equipment, required spill management team 

tabletop exercises, procedures for spill notification to government agencies, inventories of 

locally and nationally available response equipment, waste disposal methods and site, and 

procedures for monitoring and predicting spill movement. 

As discussed in the Initial Exploration Plan, Murphy will be utilizing a dynamically 

positioned drillship for the proposed activities. This vessel will be equipped with equipment 

and technology for well control and blowout prevention as a preventative measure for the 

safety of personnel and protection of the environment. If a blowout should occur, which 

results in an oil spill, Murphy’s Sub-Regional Oil Spill Response Plan addresses the 

processed for containment, recovery, and removal of the spill liquid hydrocarbons. 

 The precautions addressed in Murphy’s standard safety and environmental operating 

procedures and our Sub-Regional Oil Spill Response Plan are considered consistent with the 

state’s enforceable policies to conserve and protect marine habitat and saltwater fisheries. 

 

Chapter 372 - Wildlife 

This chapter addresses the “Florida Endangered and Threatened Species Act” and its 

implementation by the Fish and Wildlife Conservation Commission to conserve and protect 

the fish and wildlife resources of the State, particularly those species defined as endangered 

or threatened. The Fish and Wildlife Conservation Commission has established a Fish and 

Wildlife Habitat Program and a Conservation and Recreation Lands Program Trust Fund for 

acquiring and managing lands for the conservation of fish and wildlife. The enforceable 

policies direct the State of conserve its diverse fish and wildlife resources. Florida has more 

endangered or threatened species than any other continental State; therefore, the protection 

of species defined as endangered or threatened is emphasized. State lands that provide 

habitat needed by these species shall be maintained and enhanced for their value as fish and 

wildlife habitat. Substances thrown, spilled, drained, or discharged into fresh waters that 

injure or kill fish are expressly prohibited. 

As Murphy will be using the existing onshore support infrastructure in Fourchon, Louisiana; 

we do not anticipate any impact on Florida’s lands or waters to affect wildlife habitats or 

recreational lands. The most direct traffic routes for support vessels from Louisiana to De 

Soto Canyon Block 178. The authorized overboard discharges attributable to the proposed 

activities will be temporary in nature, and will be localized in the vicinity of the surface 

location for each proposed well; which should not impact Florida lands, waters or wildlife. 

Disposal of trash and debris into the receiving waters is strictly prohibited by the Bureau of 

Ocean Energy Managements/Bureau of Safety and Environmental Enforcement, US 

Environmental Protection Agency and the US Coast Guard. 

Bureau of Ocean Energy Managements/Bureau of Safety and Environmental Enforcement 

recently issued Notice to Lessees (NTL) Nos. 2012-G01 and 2012-G01 which address 

measures for preventing disposal of trash and debris overboard and subsequently 

endangering wildlife, as well as outline the requirements for posting of signs and training of 
De Soto Canyon Block 178 – Initial Exploration Plan Page 9 

Murphy Exploration & Production Company - USA 

personnel on such unauthorized disposals, as well as accident reporting related to marine 

species. 

In the event of an unanticipated blowout resulting in an oil spill, it is unlikely to have an 

impact based on the industry wide standards for using proven equipment and technology for 

such responses, implementation of our Sub-Regional Oil Spill Response Plan which address 

available equipment and personnel, techniques for containment and recovery, and removal 

of the oil spill. 

The precautions addressed in Murphy’s standard safety and environmental operating 

procedures and our Sub-Regional Oil Spill Response Plan are considered consistent with the 

state’s enforceable policies to conserve Florida’s fish and wildlife resources, including 

endangered and/or threatened species. 

Chapter 373– Water Resources 

This chapter establishes enforceable policies that guide the management and protection of 

water resources, water quality and environmental quality. The policies address the 

conservation of surface and ground waters for full beneficial use; sustainable water 

management; preservation of natural resources, fish, and wildlife; protecting public land; and 

promoting the health and general welfare of Floridians. The State manages and conserves 

water and related natural resources by determining whether activities will unreasonable 

consume water, degrade water quality, or adversely affect environmental values such as 

protected species habitat, recreational pursuits, and marine productivity. 

As Murphy will be using the existing onshore support infrastructure in Fourchon, Louisiana; 

we do not anticipate usage of any Florida water resource, nor any new construction, 

dredging, or filling on Florida’s lands or waters to affect water quality. The authorized 

overboard discharges attributable to the proposed activities will be temporary in nature, and 

will be localized in the vicinity of the surface location for each proposed well; which should 

not impact Florida lands or waters. 

In the event of an unanticipated blowout resulting in an oil spill, it is unlikely to have an 

impact based on the industry wide standards for using proven equipment and technology for 

such responses, implementation of our Sub-Regional Oil Spill Response Plan which address 

available equipment and personnel, techniques for containment and recovery, and removal 

of the oil spill. 

The precautions addressed in Murphy’s standard safety and environmental operating 

procedures and our Sub-Regional Oil Spill Response Plan are considered consistent with the 

state’s enforceable policies to conserve surface and ground waters of the State. 

Chapter 375 – Outdoor Recreation and Conservation 

This chapter discusses the “Outdoor Recreation and Conservation Act of 1963” and the 

responsibility charged to the Department of Environmental Protection (DEP) to implement 

a comprehensive outdoor recreation plan in cooperation with the Fish and Wildlife 
De Soto Canyon Block 178 – Initial Exploration Plan Page 10 

Murphy Exploration & Production Company - USA 

Conservation Commission and the water management districts. The DEP participates in the 

land and water conservation fund program to acquire lands and water areas for outdoor 

recreation, natural resource conservation, wildlife and forestry management, and water 

conservation and control. This chapter also empowers the Fish and Wildlife Conservation 

Commission to regulate motor vehicle access and traffic control on public lands. 

As Murphy will be using the existing onshore support infrastructure in Fourchon, Louisiana; 

we do not anticipate usage of any Florida’s lands or waters, and no new vehicle traffic on 

public lands. In the event of an unanticipated blowout resulting in an oil spill, it is unlikely 

to have an impact based on the industry wide standards for using proven equipment and 

technology for such responses, implementation of our Sub-Regional Oil Spill Response Plan 

which address available equipment and personnel, techniques for containment and recovery, 

and removal of the oil spill. 

The precautions addressed in Murphy’s standard safety and environmental operating 

procedures and our Sub-Regional Oil Spill Response Plan are considered consistent with the 

state’s enforceable policies to protect and maintain Florida’s lands and water areas for 

outdoor recreation, conservation, and wildlife management. 

Chapter 376– Pollution Discharge Prevention and Removal 

This chapter declares that the preservation of the seacoast as a source of public and private 

recreation and the preservation of water and certain lands are matters of the highest urgency 

and priority and shall be accomplished by maintaining surface and ground water, coastal 

waters, estuaries, tidal flats, beaches, and public lands adjoining the seacoast in as close to a 

pristine condition as possible. The discharge of pollutants into or upon any coastal waters, 

estuaries, tidal flats, beaches, and lands adjoining the seacoast of the State is declared to be 

inimical to the paramount interests of the State and is prohibited. The statute provides for 

hazards and threats of danger and damages resulting from any pollutant discharge to be 

evaluated; requires the prompt containment and removal of pollutions; provides penalties 

for violations; and ensures the prompt payment of reasonable damages from a discharge. 

Murphy has prepared a Sub-Regional Oil Spill Response Plan for the Eastern Planning Area, 

which is consistent with the requirements of the National Contingency Plan and the Oil 

Pollution Act of 1990 (OPA). 

As Murphy will be using the existing onshore support infrastructure in Fourchon, Louisiana; 

we do not anticipate any transfers between vessels and Florida onshore facilities. As to 

transfers between offshore facilities and vessels, the Sub-Regional Oil Spill Response Plan 

outlines response actions, inspection and maintenance of response equipment, required spill 

management team response drill, governmental notification procedures, inventories of 

response equipment, response team organization, and spill movement monitoring and 

contingency plans for oil spill containment, recovery and removal. 

The precautions addressed in Murphy’s standard safety and environmental operating 

procedures and our Sub-Regional Oil Spill Response Plan are considered consistent with the 
De Soto Canyon Block 178 – Initial Exploration Plan Page 11 

Murphy Exploration & Production Company - USA 

state’s enforceable policies to protect and maintain Florida’s lands and water areas for 

outdoor recreation, conservation, and wildlife management. 

Chapter 377 – Energy Resources 

The State’s policy is to conserve and control the oil and gas resources in the State, including 

products made therefrom; and to safeguard the health, property, and welfare of Floridians. 

To accomplish this, the energy resources chapter addresses the regulation, planning, and 

development of the energy resources of the State. The DEP is authorized to regulate all 

phases of exploration, drilling, and production of oil, gas, and other petroleum products in 

the State. This chapter also describes the permitting requirements and criteria necessary to 

drill and develop for oil and gas. DEP rules ensure that all precautions are taken to prevent 

the spillage of oil or any other pollutant in all phases of extraction and transportation. 

The State explicitly prohibits pollution resulting from drilling and production activities. No 

person drilling for or producing oil, gas, or other petroleum products may pollute land or 

water; damage aquatic or marine life, wildlife, birds, or public and private property; or allow 

any extraneous matter to enter or damage any mineral or freshwater bearing formation. 

Penalties for violations of any provisions of this chapter are also detailed. 

The proposed activities addressed in the De Soto Canyon Block 178 Initial Exploration Plan 

do not provide for any drilling or production activities in Florida that are regulated by the 

Florida DEP. All authorized effluents discharged overboard will be in accordance with the 

US Environmental Protection Agency’s NPDES General Permit GMG460000, and will not 

pollute Florida land or waters, damage wildlife or public or private property, or contaminate 

any mineral or freshwater bearing formation. Disposal of trash and debris into the receiving 

waters is strictly prohibited by the Bureau of Ocean Energy Managements/Bureau of Safety 

and Environmental Enforcement, US Environmental Protection Agency and the US Coast 

Guard. 

Bureau of Ocean Energy Managements/Bureau of Safety and Environmental Enforcement 

recently issued Notice to Lessees (NTL) Nos. 2012-G01 and 2012-G01 which address 

measures for preventing disposal of trash and debris overboard and subsequently 

endangering wildlife, as well as outline the requirements for posting of signs and training of 

personnel on such unauthorized disposals, as well as accident reporting related to marine 

species. 

In the event of an unanticipated blowout resulting in an oil spill, it is unlikely to have an 

impact based on the industry wide standards for using proven equipment and technology for 

such responses, implementation of our Sub-Regional Oil Spill Response Plan which address 

available equipment and personnel, techniques for containment and recovery, and removal 

of the oil spill. 

The precautions addressed in Murphy’s standard safety and environmental operating 

procedures and our Sub-Regional Oil Spill Response Plan are considered consistent with the 

state’s enforceable policies to safeguard the health, property, and welfare of Floridians and 

preventing pollution during drilling activities. 
De Soto Canyon Block 178 – Initial Exploration Plan Page 12 

Murphy Exploration & Production Company - USA 

Chapter 403 – Environmental Control 

Water Quality 

The State’s policy is to conserve the waters of the State and to protect, maintain, and 

improve the quality thereof for public water supplies, propagation of wildlife and fish and 

other aquatic life, and other beneficial uses and to provide that no wastes be discharged into 

any waters of the State without first being given the degree of treatment necessary to protect 

the beneficial uses of such water. 

As Murphy will be using the existing onshore support infrastructure in Fourchon, Louisiana; 

we do not anticipate usage of any Florida water resource, nor any new construction, 

dredging, or filling on Florida’s lands or waters to affect water quality. The authorized 

overboard discharges attributable to the proposed activities will be temporary in nature, and 

will be localized in the vicinity of the surface location for each proposed well; which should 

not impact Florida lands or waters. 

In the event of an unanticipated blowout resulting in an oil spill, it is unlikely to have an 

impact based on the industry wide standards for using proven equipment and technology for 

such responses, implementation of our Sub-Regional Oil Spill Response Plan which address 

available equipment and personnel, techniques for containment and recovery, and removal 

of the oil spill. 

The precautions addressed in Murphy’s standard safety and environmental operating 

procedures and our Sub-Regional Oil Spill Response Plan are considered consistent with the 

state’s enforceable policies to conserve surface and ground waters of the State. 

Air Quality 

Additionally, it is the policy of the State to achieve and maintain such levels of air quality as 

will protect human health and safety and, to the greatest degree practicable, prevent injury to 

plant and animal life and property. 

Routine offshore air pollutant emissions will result from both drilling rig operations, and 

helicopters and service vessels. These emissions occur mainly from combustion or burning 

of diesel fuel and from venting or evaporation of hydrocarbons. Due to the distance from 

the Florida shoreline (approximately 107 miles), routine operations in De Soto Canyon 

Block 178 will have no impact on air quality conditions along the coastline. 

Therefore, the activities proposed in the Initial Exploration Plan are consistent with the 

enforceable policies of this chapter. 

Chapter 582 – Soil and Water Conservation 

The farm, forest and grazing lands of the State are among the basic assets of the State and 

the preservation of these lands is necessary to protect and promote the health, safety, and 

general welfare of its people. It is the policy of the State to provide for control and 
De Soto Canyon Block 178 – Initial Exploration Plan Page 13 

Murphy Exploration & Production Company - USA 

prevention of soil erosion, and for the prevention of floodwater and sediment damages, and 

for furthering the conservation, development, and utilization of soil and water resources, and 

thereby to preserve natural resources. 

As Murphy will be using the existing onshore support infrastructure in Fourchon, Louisiana; 

we do not anticipate usage of any Florida’s lands or waters. In the event of an unanticipated 

blowout resulting in an oil spill, it is unlikely to have an impact based on the industry wide 

standards for using proven equipment and technology for such responses, implementation 

of our Sub-Regional Oil Spill Response Plan which address available equipment and 

personnel, techniques for containment and recovery, and removal of the oil spill. 

The precautions addressed in Murphy’s standard safety and environmental operating 

procedures and our Sub-Regional Oil Spill Response Plan are considered consistent with the 

state’s enforceable policies to conserve and preserve the land and water resources of the 

State.
Murphy Exploration & Production Company – USA Attachment R 

Alabama Coastal Management Program Page 1 

COASTAL ZONE MANAGEMENT 

STATE OF ALABAMA ENFORCEABLE POLICIES 
Murphy Exploration & Production Company – USA Attachment R 

Alabama Coastal Management Program Page 2 

STATE OF ALABAMA 

COASTAL ZONE CONSISTENCY ENFORCEABLE POLICIES 

Coastal Resource Use Policies 

1. Coastal Development 

Coastal regions are likely sites for port, industrial, urban/suburban and energy 

development facilities. It is the policy of the Alabama Coastal Area Management 

Program to provide assistance within its means to facilitate a productive and 

environmental responsible port, industrial, urban/suburban and energy development 

facilities. 

The proposed activities are located in OCS Federal Waters, Gulf of Mexico, 

approximately 100 miles from the nearest Alabama shoreline and 145 miles to the 

existing onshore support base located in Fourchon, Louisiana. 

The proposed activities are not anticipated to have an impact on the Alabama 

coastline. The drilling and construction activities will be short in duration, and the 

minimal well protector structure and associated production operations will require 

minimal support activity. 

2. Mineral Resource Exploration and Extraction 

Clay, sand, and gravel are mined in limited quantities from Alabama’s coastal river 

bottoms and stream cuts. This resource extraction is vital to certain sections of the 

Alabama economy, and the associated land processes produce short and long term 

adverse impacts to the coastal area and resources. This activity contributes to the 

overall suspended sediment load in coastal area water bodies, destroys wildlife 

habitat, changes the visual quality of the landscapes and, irretrievably, consumes the 

depleted mineral resources. It is the policy of the Alabama Coastal Management 

Plan to encourage mining operations, and directly related development, engaged in 

the extraction and/or processing of construction sand, industrial sand, gravel, and 

other minerals to avoid hydrological sensitive areas, including oyster reefs, 

submerged grassbeds, and other productive shallow water areas, with the exception 

of those activities related to beach nourishment and shoreline stabilization. 

The proposed activities do not provide for the extraction of solid minerals from the 

State of Alabama. These activities provide for the exploration of oil and gas 

hydrocarbons located in OCS Federal Waters, Gulf of Mexico, approximately 100 

miles from the nearest Alabama shoreline. 
Murphy Exploration & Production Company – USA Attachment R 

Alabama Coastal Management Program Page 3 

3. Commercial Fishing 

Alabama’s fishing industry is one of the most important uses of Alabama’s natural 

coastal assets and the major economic factor in several Mobile and Baldwin County 

communities. The abundance of commercial species, especially shrimp, is heavily 

dependent upon the presence of extensive wetland areas for nursery grounds and 

good. Physical alterations of the estuarine environment that affects certain species of 

marine organisms are dredge spoil disposal, bacterial pollutions, heavy metals and 

toxic chemicals discarded by industries. 

It is the policy of the Alabama Coastal Area Management Program to encourage the 

protection and enhancement of the water quality and wetland resources of the 

coastal area of Alabama in order to protect and enhance the aquatic resources; and to 

identify, expand and enhance existing essential habitat in an effort to extend the 

productivity of the ecosystem. 

The proposed activities at De Soto Canyon Block 178 will be located approximately 

100 miles from the nearest Alabama shoreline. Murphy Exploration & Production 

Company - USA does not propose any dredging and/or spoil deposition as a result 

of the proposed activities. The authorized effluents to be discharged during the 

proposed drilling operations may temporarily affect water quality in the immediate 

vicinity of each discharge point associated with each well location. Water quality is 

expected to return to normal in the area following the cessation of operations. Due 

to the low toxicity and rapid dispersion of these discharges, little or no impact on 

water column biota is likely, including fish larvae that recruit to near shore nursery 

areas. 

 

The overboard authorized effluents of drilling fluids and associated cuttings may 

increase sedimentation rate around the well location, possibly causing burying or 

smothering of some benthic organisms. Results of previous monitoring programs 

and modeling studies suggest that burial would most likely occur within an area of a 

few hectares around each well location. Recovery from these temporary impacts is 

expected over a period of months to years. 

Other minor authorized effluents discharged overboard may include sanitary and 

domestic waste, deck drainage from the drilling unit, uncontaminated seawater for 

cooling machinery, and desalination brine. Such discharges may case localized, 

short-term impacts on water quality near the discharge points for each well location. 

There is a very low probability that a diesel spill may occur while conducting transfer 

operations from the supply vessel to the MODU. Murphy Exploration & 

Production Company - USA’s Regional Oil Spill Response Plan discusses any 

potential impacts from these types of spills on Alabama’s coastal zone. This Plan 

also describes response actions for specific hypothetical spill events, provisions and 

approvals required for the use of a dispersants by boat or aerial application, 

provisions for inspection and maintenance of response equipment, required spill 

management team tabletop exercises, procedures for spill notification to government 
Murphy Exploration & Production Company – USA Attachment R 

Alabama Coastal Management Program Page 4 

agencies, inventories of locally and nationally available response equipment, waste 

disposal methods and site, and procedures for monitoring and predicting spill 

movement. 

As discussed in the Initial Exploration Plan, Murphy Exploration & Production 

Company - USA will be utilizing a drilling unit equipped with equipment and 

technology for well control and blowout prevention as a preventative measure for 

the safety of personnel and protection of the environment. If a blowout should 

occur, which results in an oil spill, Murphy’s Regional Oil Spill Response Plan 

addresses the processed for containment, recovery, and removal of the spill liquid 

hydrocarbons. 

The precautions addressed in Murphy’s standard safety and environmental operating 

procedures and our Regional Oil Spill Response Plan are considered consistent with 

the state’s enforceable policies to conserve and protect marine habitat and saltwater 

fisheries. 

4. Hazard Management 

Natural hazards such as storms and hurricanes can change the natural beach and 

dune systems. Human activities such as construction on dune systems and 

construction of seawalls, bulkheads or jetties can have an adverse effect on adjacent 

properties and property forward of vertical structures. The Alabama Coastal Area 

Management Program recognizes that dynamic, unpredictable and damaging natural 

events such as floods, hurricanes and erosion, occurring within the coastal area are 

part of the necessary cyclical functions needed to maintain the natural environment. 

However, the effects of these natural hazard events must be managed, by means of 

mitigating as a strategy that necessitates proper planning. It is the policy of the 

Alabama Coastal Area Management Program to encourage land-use planning that 

avoids or eliminates development in hazardous coastal areas prone to loss due to 

flood, hurricane surge and/or erosion. 

The proposed activities in De Soto Canyon Block 178 should not impact Alabama’s 

measures to protect the coastal area from natural hazards. Furthermore, since the 

proposed operations are temporary in nature, Murphy does not propose or anticipate 

the need to develop any coastal/onshore sites which could have an adverse effect. 

Murphy has adopted industry standards for conducting the proposed exploration 

operations. Such standards are adopted to prevent unanticipated occurrences such 

as a well blowout or oil spill release, which could potentially cause adverse water/air 

environmental consequences. Such anticipated occurrences will be handled as 

quickly as possible by Murphy implementing their Regional Oil Spill Response Plan 

and/or well control standards and procedures. 
Murphy Exploration & Production Company – USA Attachment R 

Alabama Coastal Management Program Page 5 

5. Shoreline Erosion 

Shorelines are the transitional areas between water and land because of their location. 

These shorelines represent the most dynamic interface in the coastal area and are 

very productive. Their continuous change from wet to dry conditions result in 

diverse habitats and ecosystems. The shorelines of the Alabama coastal area provide 

the State and its citizens with many direct and indirect benefits of great value. At the 

same time, they are highly vulnerable to the pressures of development and to a 

variety of natural hazards, most notably erosion. Construction and development are 

primary activities affecting the Alabama shoreline. As development intensifies, the 

natural topography diminishes critical habitat and creates hazards or intensifies 

existing hazards. Therefore, it is the policy of the Alabama Coastal Area 

Management Program to encourage the maintenance and stability of Alabama’s 

natural shoreline and shoreline resources and to minimize erosion by assuring 

compatibility of shoreline uses. 

Murphy will be using the existing onshore support infrastructure located in 

Fourchon, Louisiana; and as such does not anticipate a need for new development, 

construction, dredging or filling activities on Alabama’s lands or waters. All travel 

routes to and from the onshore support base and the offshore locations in De Soto 

Canyon Block 178 will avoid any recreational trail systems established by the State of 

Alabama. Therefore, the proposed activities are consistent with the enforceable 

policies of this chapter. 

6. Recreation 

Alabama’s recreational opportunities are centered around the water resources and 

include, but are not limited to, sport fishing, boating, swimming and sightseeing. 

There is an increasing demand for recreational opportunities, both public and 

private, in Alabama’s coastal area; as evidenced by the increased number of boater 

registrations, waterfront developments and demand for permit requests for private 

docks, harbors and marinas. It is the policy of the Alabama Coastal Area 

Management Program to safeguard public access to and use of coastal lands and 

waters such as beaches and shorelines, boat landings, and fishing grounds. 

 

Murphy will be using the existing onshore support infrastructure located in 

Fourchon, Louisiana, and will utilize the most direct travel routes to and from the 

onshore support base and the offshore location in De Soto Canyon Block 178, and 

will take measures to avoid any recreational systems recognized by the State of 

Alabama, and do not anticipate usage of any Alabama lands or waters, and no new 

vehicle traffic on public lands. 

In the event of an unanticipated blowout resulting in an oil spill, it is unlikely to have 

an impact based on the industry wide standards for using proven equipment and 

technology for such responses, implementation of our Regional Oil Spill Response 

Plan which address available equipment and personnel, techniques for containment 

and recovery, and removal of the oil spill. 
Murphy Exploration & Production Company – USA Attachment R 

Alabama Coastal Management Program Page 6 

The precautions addressed in our standard safety and environmental operating 

procedures and our Regional Oil Spill Response Plan are considered consistent with 

the state’s enforceable policies to protect and maintain Alabama’s lands and water 

areas for outdoor recreation, conservation, and wildlife management. 

7. Transportation 

The State of Alabama is responsible for approving plans for the location, 

construction and maintenance of the state highway system and public roads and the 

location, construction, and maintenance of individual state highway system projects. 

Rules and project approvals governing transportation projects within the coastal 

zone must comply with the policies in this category. Standard specifications include 

measures for erosion and sedimentation control, waste disposal, earthwork, and revegetation during construction. 

The major operations proposed in this Plan at De Soto Canyon Block 178 are 

temporary in nature. Additionally, Murphy will be using an existing infrastructure in 

Fourchon, Louisiana for its onshore support operations. Therefore, we do not 

anticipate any impact on the State of Alabama’s transportation system. 

Natural Resource Protection Policies 

1. Biological Productivity 

Biologically, more than 90% of all Alabama’s commercial and recreational fishing 

dollars are dependent on estuaries like Mobile Bay, Weeks Bay and Perdido Bay, 

which provide habitat for one or more critical life stages for species of fish and 

shellfish. Protective functions if the coastal area and coastal resources are 

instrumental in ecosystem preservation and enhancement. 

The proposed surface disturbances in De Soto Canyon Block 178 will be located 

approximately 100 miles from the nearest Alabama shoreline and 145 miles to the 

existing onshore support base to be located in Fourchon, Louisiana. These 

proposed major activities (drilling) are temporary in nature, and we do not anticipate 

an adverse impact on the biological productivity of the coastal area and/or coastal 

resources. 

2. Water Quality 

The policies address the conservation of surface and ground waters for full beneficial 

use; sustainable water management; preservation of natural resources, fish, and 

wildlife; protecting public land; and promoting the health and general welfare of the 

general public in Alabama. The State manages and conserves water and related 

natural resources by determining whether activities will unreasonable consume water, 
Murphy Exploration & Production Company – USA Attachment R 

Alabama Coastal Management Program Page 7 

degrade water quality, or adversely affect environmental values such as protected 

species habitat, recreational pursuits, and marine productivity. 

As Murphy will be using the existing onshore support infrastructure in Fourchon, 

Louisiana we do not anticipate usage of any Alabama water resource, nor any new 

construction, dredging, or filling on Alabama’s lands or waters to affect water quality. 

The authorized overboard discharges attributable to the proposed activities will be 

temporary in nature, and will be localized in the vicinity of the surface location of the 

proposed well and associated pipeline route; which should not impact Alabama lands 

or waters. 

In the event of an unanticipated blowout resulting in an oil spill, it is unlikely to have 

an impact based on the industry wide standards for using proven equipment and 

technology for such responses, implementation of our Regional Oil Spill Response 

Plan which address available equipment and personnel, techniques for containment 

and recovery, and removal of the oil spill. 

The precautions addressed in our standard safety and environmental operating 

procedures and our Regional Oil Spill Response Plan are considered consistent with 

the state’s enforceable policies to conserve surface and ground waters of the State. 

Overboard discharges (i.e., drilling fluids and associated cuttings) associated with the 

proposed activities must be tested first for toxicity limitations as mandated by EPA’s 

Region IV NPDES General Permit. Other solid waste such as ground food will first 

pass through a 25-millimeter type mesh screen before being discharged overboard, as 

regulated by the U.S. Coast Guard’s Marine Pollution Research and Control Act 

(MARPOL) of 1987. Solid wastes will be collected and stored on the facility, and 

then transported by an offshore support vessel to an authorized onshore disposal 

site with the State of Louisiana. These wastes will be manifested and disposed as per 

the State of Louisiana Department of Environmental Quality’s regulations. 

3. Water Resources 

In the coastal area, two important reasons for managing water resources and 

protecting water quality are the availability of adequate supplies of clean, safe waters 

for private, public and industrial consumers, and to protect the water quality for 

managing most of the other coastal area resources. The key to protecting the quality 

of the water resources is to manage the impacts to Alabama’s bays, tidal streams, 

estuaries, wetlands and near shore waters. 

The proposed surface disturbances in De Soto Canyon Block 178 will be located 

approximately 100 miles from the nearest Alabama shoreline and the existing 

onshore support base to be located in Fourchon, Louisiana. These proposed major 

activities (drilling and pipeline installation) are temporary in nature, and do not 

include any permanent installations which may have an impact on area runoff in 

coastal waters. 
Murphy Exploration & Production Company – USA Attachment R 

Alabama Coastal Management Program Page 8 

4. Air Quality 

The quality of air in the Alabama coastal area affects many aspects of the 

environment that directly relate to the quality of life on the coastal area. The coastal 

area of Alabama is rapidly expanding, and the increased coastal urbanization and 

industrial development and increased motor vehicle traffic have increased the 

amount and complexity of air pollution. Therefore, it is the policy of the Coastal 

Area Management Program to encourage all sources of air pollution in Alabama’s 

coastal area meet or exceed all applicable emission standards. 

Air emissions associated with the proposed activities in De Soto Canyon Block 178 

have been projected using a matrix and formula supplied by the Bureau of Ocean 

Energy Management/Bureau of Safety and Environmental Enforcement who has 

primacy from the Environmental Protection Agency for regulating such emissions. 

The resultant emissions are below the exemption levels for Carbon Monoxide, 

Particulate Matter, Sulphur Oxides, Nitrogen Oxides and Volatile Organic 

Compounds. 

5. Wetlands and Submerged Grassbeds 

The State of Alabama has dominion and control of submerged lands extending three 

miles seaward from its coast. Proper management ensures the continued viability of 

this resource and prevents obstructions to navigation, reductions in water quality, 

biological diversity and production, and restriction of public access. It is the policy 

of the Alabama Coastal Area Management Program to encourage the protection of 

wetlands and submerged grassbeds to maintain or increase the vital role they play in 

the coastal ecosystem and the coastal quality of life. 

The proposed activities addressed in this Plan will be located 100 miles from the 

nearest Alabama shoreline, with an existing onshore support infrastructure in 

Fourchon, Louisiana. Therefore, Murphy does not anticipate an impact on 

associated wetlands and submerged grassbeds as a result of the proposed activities. 

 

6. Beach and Dune Protection 

Beach and dune systems are dynamic and respond to the many forces of the sea. 

Their characteristics serve to buffer and cushion against wave attach and, therefore, 

are the first line of defense against the destructive and erosive forces of the sea, 

Beach and dune systems also re-supply the land-water interface before, during and 

after periods of high energy conditions (wave actions). Beach and dune systems 

cover approximately 10,000 acres along Alabama’s shoreline and are highly 

productive and protective to the coastal area. Protection and preservation of these 

systems in a natural state it vital. Loss of beaches and dunes eliminates wildlife, 

habitat, reduces buffers protecting inland areas from the forces of storms, and 

significantly impacts the Alabama economy. Therefore, it is the policy of the 

Alabama Coastal Zone Management Program to encourage the maintenance of the 
Murphy Exploration & Production Company – USA Attachment R 

Alabama Coastal Management Program Page 9 

natural attributes of beach and dune systems in the Alabama coastal area and to 

assure adequate public access. 

The offshore activities to be conducted in De Soto Canyon Block 178 will be located 

approximately 100 miles from the nearest Alabama coastline; whereas the onshore 

support operations will be conducted from an existing infrastructure located in 

Fourchon, Louisiana. The onshore support and offshore activities should not have 

an impact on the coastal areas of the State of Alabama. The transportation modes 

from the onshore support base in Fourchon, Louisiana to De Soto Canyon Block 

178 will be in excess of 100 miles from the coastal shoreline to the offshore 

activities. 

In the event of an unanticipated blowout resulting in an oil spill, it is unlikely to have 

an impact based on the industry wide standards for using proven equipment and 

technology for such responses, implementation of our Regional Oil Spill Response 

Plan which address available equipment and personnel, techniques for containment 

and recovery, and removal of the oil spill. 

The precautions addressed in our standard safety and environmental operating 

procedures and our Regional Oil Spill Response Plan are considered consistent with 

the policies for protecting beach and shore preservation. 

7. Wildlife Habitat Protection 

The enforceable policies direct the State of conserve its diverse fish and wildlife 

resources, with emphasis on the protection of species defined as endangered or 

threatened. State lands that provide habitat needed by these species shall be 

maintained and enhanced for their value wildlife habitat. Substances thrown, spilled, 

drained, or discharged into fresh waters that injure or kill fish are expressly 

prohibited. 

As Murphy will be using the existing onshore support infrastructure in Fourchon, 

Louisiana; we do not anticipate any impact on Alabama lands or waters to affect 

wildlife habitats. The most direct traffic routes will be for used for support vessels 

to and from De Soto Canyon Block 178. The authorized overboard discharges 

attributable to the proposed activities will be temporary in nature, and will be 

localized in the vicinity of the surface location for the proposed well; which should 

not impact Alabama lands, waters or wildlife. Disposal of trash and debris into the 

receiving waters is strictly prohibited by the Bureau of Ocean Energy 

Management/Bureau of Safety and Environmental Enforcement, US Environmental 

Protection Agency and the US Coast Guard. Implementation of a stipulation 

attached to the oil and gas leases address the measures for preventing disposal of 

trash and debris overboard and subsequently endangering wildlife. Bureau of Ocean 

Energy Management/Bureau of Safety and Environmental Enforcement recently 

issued Notice to Lessees No. 2012-G01 and 2012-JOINT-G01 outlining the 

requirements for posting of signs and training of personnel on such unauthorized 

disposals, as well as accident reporting related to marine species. 
Murphy Exploration & Production Company – USA Attachment R 

Alabama Coastal Management Program Page 10 

The precautions addressed in our standard safety and environmental operating 

procedures and our Regional Oil Spill Response Plan are considered consistent with 

the state’s enforceable policies to conserve Alabama’s wildlife resources, including 

endangered and/or threatened species. 

8. Endangered Species 

Coastal area habitats are important in the life-cycles for many endangered and 

threatened species, migratory birds, waterfowls, and terrestrial species and, of course, 

finfish and shellfish. Therefore, it is the policy of the State of Alabama Coastal Area 

Management Program to promote the preservation of these habitats which are 

important to the endangered species. 

The proposed activities addressed in this Plan are temporary in nature and will be 

located approximately 100 miles from the nearest Alabama shoreline; therefore, 

Murphy does not anticipate an impact on these areas and species. 

9. Cultural Resources Protection 

The cultural resources of the Alabama coastal area include historical resources, 

architectural resources, archaeological resources and heritage resources. The 

importance of cultural resources is that they allow insight into the past inhabitants of 

the coastal area and provide valuable information and clues to understanding the 

conditions of the past natural environment. Therefore, it is the policy of the State of 

Alabama Coastal Area Management Program to promote the preservation of cultural 

resources and to insure that the knowledge of Alabama’s history and pre-history is 

not lost. 

The proposed activities are located in De Soto Canyon Block 178, and are within a 

high probability area for potential pre-historic archaeological resources. Results of 

the archaeological survey do not indicate the presence of any potential cultural 

resources within the vicinity of the proposed surface disturbance. 
Florida’s Cross Reference Documentation 

Attachment S 

(Public Information) 
State of Florida 

Cross Reference Data 

Initial Exploration Plan (IEP) 

De Soto Canyon Block 178 (Lease OCS-G 25850) 

A. Plan Contents 

a. Pollution Prevention Measures – discussion of measures taken to prevent the discharge of 

oils and greases from drilling rigs or platforms during rainfall and routine operations. 

i. IEP – Bullet E.

b. Additional Measures – discussion of the safety, pollution prevention, and early spill 

detection measures to be taken beyond those required by 30 CFR part 550. 

i. IEP – Bullet F.

B. General Information 

a. Drilling Fluids – table of information on the types and amounts of drilling fluids to be 

used while drilling the proposed wells. 

i. IEP – Bullet B.

b. Blowout Scenario – scenario for a potential blowout of the well from which Murphy 

expects to have the highest volume of liquid hydrocarbons. 

i. IEP – Bullet G.

C. Biological, Physical, and Socioeconomic Information 

a. Threatened and Endangered Species Information – discussion on the presence of threatened 

and endangered species in the area of the proposed activities. 

i. IEP – Bullet H.

ii. Attachment T – EIA, Section C.3

b. Archaeological Report – not applicable to the proposed activities. 

i. IEP – Bullet I.

ii. Attachment T – EIA, Section C.6

c. Air and Water Quality Information – discussion of air and water quality in and adjacent 

to the area of the proposed activities. 

i. IEP – Bullet J.

ii. Attachment T – EIA, Section C.1

d. Socioeconomic Information – not applicable to the proposed activities. 

i. IEP – Bullet K.

ii. Attachment T - EIA – Section C.8

D. Waste and Discharge Information 

a. Projected Generated Wastes – table of projected solid and liquid wastes likely to be 

generated by the proposed activities. 

i. IEP – Bullet A.

ii. Attachment L 

b. Projected Ocean Discharges – table on solid or liquid wastes to be discharged overboard. 

i. IEP – Bullet B.

ii. Attachment L
E. Oil Spill Information 

a. Oil Spill Response Planning – information on type of Sub-Regional Oil Spill Response 

Plan being submitted to address the proposed activities. 

i. IEP – Bullet A.

b. Oil Spill Response Discussion – discussion of the response to an oil spill which could result 

from the activities proposed in the Plan. 

i. IEP – Bullet E.

ii. Attachment N

c. Modeling Report – information on the modeling of a potential oil or hazardous substance 

spill. 

i. IEP – Bullet F and G.

ii. Attachment O

F. Environmental Mitigation Measures Information – measures to be taken to avoid, 

minimize, and mitigate impacts to marine and coastal environments and habitats, biota, and 

threatened and endangered species. 

a. IEP – Section I

b. Attachment T – EIA, Section C.2, C.3, C.4, C.6

G. Support Vessels and Aircraft Information 

a. Diesel Oil Supply Vessels – information on vessels to be used to supply diesel fuel. 

i. IEP – Bullet B.

b. Drilling Fluids Transportation – information on projected drilling fluids to be transported 

from onshore support facilities to proposed drilling operations. 

i. IEP – Bullet C.

c. Solid and Liquid Wastes Transportation – information on transport of any solid or liquid 

wastes from the site of the proposed activities to other offshore structures or to 

temporary or permanent onshore facilities for storage or disposal. 

i. IEP – Bullet D.

ii. Attachment L

H. Onshore Support Facilities Information 

a. Support Base Construction or Expansion – not applicable to the proposed activities.

i. IEP – Bullet B

ii. Attachment T – EIA, Page 59

b. Support Base Construction or Expansion Timetable – not applicable to the proposed 

activities.

i. IEP – Bullet C.

ii. Attachment T – EIS, Page 60
Environmental Impact Analysis 

Attachment T 

(Public Information) 
Environmental Impact Analysis

INITIAL EXPLORATION PLAN

De Soto Canyon Block 178 (OCS-G 25850)

Offshore Alabama and Florida

March 2013

Prepared for:

Robert Lanza

Murphy Exploration & Production Company, USA

16290 Katy Freeway, Suite 600

Houston, Texas 77094

Telephone: (281) 675-9135

Prepared by:

CSA Ocean Sciences Inc.

8502 SW Kansas Avenue

Stuart, Florida 34997

Telephone: (772) 219-3000
De Soto Canyon Block 178 March 2013

Environmental Impact Analysis for Initial Exploration Plan Page ii

Contents

Page

Introduction ................................................................................................................1

A. Impact-Producing Factors .......................................................................................5

A.1 Drilling Rig Presence (including noise and lights) ..........................................................................................5

A.2 Physical Disturbance to the Seafloor.............................................................................................................5

A.3 Air Pollutant Emissions ..................................................................................................................................8

A.4 Effluent Discharges........................................................................................................................................8

A.5 Water Intake ..................................................................................................................................................8

A.6 Onshore Waste Disposal................................................................................................................................9

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

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

A.9 Accidents......................................................................................................................................................10

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

A.9.2 Small Fuel Spill ................................................................................................................................10

A.9.3 Crude Oil Spill (Worst Case Discharge)............................................................................................11

A.9.4 Other Accidents Not Analyzed in Detail..........................................................................................15

B. Affected Environment...........................................................................................16

C. Impact Analysis.....................................................................................................18

C.1 Physical/Chemical Environment ..................................................................................................................18

C.1.1 Air Quality .......................................................................................................................................18

C.1.2 Water Quality..................................................................................................................................21

C.2 Seafloor Habitats and Biota .........................................................................................................................23

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

C.2.2 High-Density Deepwater Benthic Communities..............................................................................26

C.2.3 Designated Topographic Features ..................................................................................................28

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

C.2.5 Eastern Gulf Live Bottoms...............................................................................................................29

C.3 Threatened, Endangered, and Protected Species and Critical Habitat........................................................29

C.3.1 Sperm Whale (Endangered)............................................................................................................31

C.3.2 West Indian Manatee (Endangered)...............................................................................................34

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

C.3.4 Non-Endangered Marine Mammals (Protected) ............................................................................36

C.3.5 Sea Turtles (Endangered/Threatened)............................................................................................39

C.3.6 Piping Plover (Threatened) .............................................................................................................42

C.3.7 Whooping Crane (Endangered).......................................................................................................44

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

C.3.9 Smalltooth Sawfish (Endangered)...................................................................................................45

C.3.10 Beach Mice (Endangered)...............................................................................................................46

C.3.11 Elkhorn Coral (Endangered)............................................................................................................46

C.4 Coastal and Marine Birds.............................................................................................................................47

C.4.1 Marine Birds....................................................................................................................................47

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

C.5 Fisheries Resources......................................................................................................................................52

C.5.1 Pelagic Communities and Ichthyoplankton.....................................................................................52
Contents

(Continued)

Page

De Soto Canyon Block 178 March 2013

Environmental Impact Analysis for Initial Exploration Plan Page iii

C.5.2 Essential Fish Habitat......................................................................................................................54

C.6 Archaeological Resources............................................................................................................................57

C.6.1 Shipwreck Sites ...............................................................................................................................57

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

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

C.8 Socioeconomic and Other Resources ..........................................................................................................62

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

C.8.2 Public Health and Safety .................................................................................................................63

C.8.3 Employment and Infrastructure......................................................................................................64

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

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

C.8.6 Other Marine Uses..........................................................................................................................66

D. Environmental Hazards.........................................................................................67

D.1 Geologic Hazards .........................................................................................................................................67

D.2 Severe Weather ...........................................................................................................................................67

D.3 Currents and Waves.....................................................................................................................................67

E. Alternatives ..........................................................................................................68

F. Mitigation Measures.............................................................................................68

G. Consultation .........................................................................................................68

H. Preparers..............................................................................................................68

I. References.............................................................................................................69
De Soto Canyon Block 178 March 2013

Environmental Impact Analysis for Initial Exploration Plan Page iv

List of Tables

Table Page

1 Notices to Lessees and Operators (NTLs) applicable to this Environmental Impact 

Analysis (EIA) .........................................................................................................................3

2 Matrix of impact-producing factors and affected environmental resources........................6

3 Conditional probabilities expressed as percent chance that an oil spill starting at 

Launch Point 2 will contact a certain parish, county, or coastline within 120 days 

(Modified from: BOEM, 2012c, Appendix C).......................................................................13

4 Benthic community data from stations near the lease area and in greater water 

depths and more distant stations in more similar depths sampled during the 

Northern Gulf of Mexico Continental Slope Habitats and Benthic Ecology Study 

(Adapted from: Wei, 2006; Rowe and Kennicutt, 2009).....................................................23

5 Federally listed endangered and threatened species potentially occurring in the 

lease area and along the northern Gulf Coast ....................................................................29

List of Figures

Figure Page

1 Location of De Soto Canyon Block 178..................................................................................2

2 Bathymetric map of the lease area showing the surface hole locations of Wells 

"A", "B," and "C" in De Soto Canyon Block 178...................................................................17

3 Location of selected environmental features in relation to the lease area........................43
De Soto Canyon Block 178 March 2013

Environmental Impact Analysis for Initial Exploration Plan Page v

Acronyms and Abbreviations

ADIOS2 Automated Data Inquiry for Oil Spills 2

bbl barrel

BOEM Bureau of Ocean Energy Management

BOEMRE Bureau of Ocean Energy Management, 

Regulation and Enforcement

BOP blowout preventer

BOPD barrels of oil per day

B.P. Before Present

BSEE Bureau of Safety and Environmental 

Enforcement

CEI Coastal Environments, Inc.

CH4 methane

CO carbon monoxide

CO2 carbon dioxide

CFR Code of Federal Regulations

DC De Soto Canyon

DP dynamically positioned 

EP Exploration Plan 

EEZ Exclusive Economic Zone

EFH Essential Fish Habitat

EIA Environmental Impact Analysis

EIS Environmental Impact Statement

ESA Endangered Species Act

FAD fish-attracting device

FR Federal Register

GEMS Geoscience Earth & Marine Services, 

Inc.

GHG greenhouse gas

GPS global positioning system

GMFMC Gulf of Mexico Fishery Management 

Council

H2S hydrogen sulfide

HAPC Habitat Area of Particular Concern

IPF impact-producing factor

MARPOL International Convention for the 

Prevention of Pollution from Ships

MMBO million barrels of oil

MMC Marine Mammal Commission

MMPA Marine Mammal Protection Act

MMS Minerals Management Service

Murphy Murphy Exploration & Production 

Company, USA

NAAQS National Ambient Air Quality 

Standards

NMFS National Marine Fisheries Service

NOAA National Oceanic and Atmospheric 

Administration

NOx nitrogen oxides

NO2 nitrogen dioxide

NPDES National Pollutant Discharge 

Elimination System

NPS National Park Service

NRDA Natural Resource Damage Assessment

NTL Notice to Lessees and Operators

NWR National Wildlife Refuge

OBM oil-based mud

OCS Outer Continental Shelf

OSAT Operational Scientific Advisory Team

OSRA Oil Spill Risk Analysis

OSRP Oil Spill Response Plan

PAH polycyclic aromatic hydrocarbon

PEA Programmatic Environmental 

Assessment

PM particulate matter

PSD Prevention of Significant Deterioration

ROV remotely operated vehicle

SBM synthetic-based mud

SHL surface hole location

SOx sulfur oxides

SWSS Sperm Whale Seismic Study

USCG U.S. Coast Guard

USEPA U.S. Environmental Protection Agency

USFWS U.S. Fish and Wildlife Service

VOC volatile organic compound

WCD worst case discharge
De Soto Canyon Block 178 March 2013

Environmental Impact Analysis for Initial Exploration Plan Page 1

Introduction

This Environmental Impact Analysis (EIA) was prepared on behalf of Murphy Exploration and 

Production Company, USA (Murphy) for submittal to the Bureau of Ocean Energy Management

(BOEM). The EIA evaluates the impacts of drilling activities proposed by Murphy in its Initial 

Exploration Plan (EP) for De Soto Canyon Block 178 (DC 178). 

Murphy is submitting this Initial EP for the drilling and temporary abandonment of three well 

locations, A, B and C, in DC 178. All surface hole locations (SHLs) and bottom hole locations for 

the wells will be in DC 178. This EIA provides information on the exploratory wells based on the

SHLs. The Initial EP also addresses Notice to Lessees and Operators (NTL) 

2010-N06 requirements.

The lease area is approximately 75 statute miles (121 km) from the nearest shoreline

(Louisiana), 107 statute miles (172 km) from the nearest Florida shoreline, 145 statute miles 

(233 km) from the onshore support base at Port Fourchon, Louisiana, and 155 statute miles 

(250 km) from the helicopter base at Galliano, Louisiana (Figure 1). Water depths at the 

wellsites range from approximately 6,567 to 6,580 ft (2,002 to 2,006 m). The drilling rig will be 

the dynamically positioned (DP) drillship Transocean Discoverer Deep Seas or an equivalent rig.

This EIA was prepared for submittal to the BOEM in accordance with applicable regulations and 

is a project- and site-specific analysis of Murphy’s planned activities. An EIA is a project-specific 

analysis that focuses on the impacts of a specific plan to the extent feasible. The lease area is in 

Grid 18 in the Central Gulf of Mexico Planning Area, and a Programmatic Environmental 

Assessment (PEA) was prepared (Minerals Management Service [MMS], 2003) to address 

exploration activities in the PEA lease sale area, which includes DC 178. Potential impacts have 

been analyzed at a broader level in the Final Programmatic Environmental Impact Statements

(EISs) for the Outer Continental Shelf (OCS) Oil and Gas Leasing Program (MMS, 2007a; BOEM, 

2012a) and in lease sale EISs for the Western and Central Gulf of Mexico Planning Areas 

(MMS, 2007b; BOEM, 2012b,c). The analyses from these documents are incorporated here by 

reference. Updated environmental baseline information relative to the Macondo incident 

presented in the Final Supplemental EIS for Central Planning Lease Sale 216/222 (BOEM, 2012c) 

has also been incorporated.

Statistics from offshore drilling in the U.S. Gulf of Mexico provide a reasonable basis for 

evaluating oil spill risk during exploratory drilling. According to Holand (1997), the average 

frequency of a loss of well control incident or "blowout" during exploratory drilling in the 

U.S. Gulf of Mexico is 0.00593 blowouts per well drilled, or one blowout per 169 exploration 

wells drilled. Similarly, the MMS Safety and Environmental Management Program blowout 

incident rate for 1996 to 1999 was approximately five blowouts per 1,000 well starts, or one 

blowout per 200 well starts (MMS, 2000). BOEM (2012a) recently assessed the risk of low 

probability discharge events from loss of well control events from 1964 to 2010 and found that 

of the 278 loss of well control events in the Gulf of Mexico, 59 (21%) resulted in oil pollution 

events. In its Final Supplemental EIS for the Central Gulf of Mexico Planning Area, BOEM 

confirmed that "significant changes to the spill rates for the entire OCS are not anticipated"

(BOEM, 2012c).
De Soto Canyon Block 178 March 2013

Environmental Impact Analysis for Initial Exploration Plan Page 2

Figure 1. Location of De Soto Canyon Block 178.
De Soto Canyon Block 178 March 2013

Environmental Impact Analysis for Initial Exploration Plan Page 3

Historically, most blowouts have not resulted in oil spills. Of 151 well blowouts in the 

Gulf of Mexico from 1971 to 1995, only 18 (12%) resulted in oil spills, with a total combined 

volume of 1,000 barrels (bbl) of crude oil and condensate released (MMS, 2000). Between 1964 

and 1999, almost all offshore spills (94%) from drilling and production-related operations on the 

OCS were <1 bbl in size (Anderson and LaBelle, 2000). According to the Bureau of Safety and 

Environmental Enforcement (BSEE) Final Drilling Safety Rule (75 Federal Register [FR] 63365)

issued following the Macondo incident, the baseline risk of a catastrophic blowout is estimated 

to be about once every 26 years.

Oil spill response-related activities for facilities included in the Initial EP will affect the 

State of Florida; therefore, Murphy has a Sub-Regional Oil Spill Response Plan approved in 

August 2011 with subsequent and ongoing modifications to meet regulatory and operational 

requirements. The latest update of July 2012 submitted to BSEE due to NTL 2012-N06 is 

awaiting approval. Murphy will demonstrate oil spill financial responsibility for the facilities 

proposed in this Initial EP according to 30 CFR Part 254 and NTL 2008-N05, “Guidelines for Oil 

Spill Financial Responsibility for Covered Facilities.”

This EIA is organized into Sections A through I corresponding to the information required by 

NTL 2008-G04. The main impact-related discussions are in Section A (Impact-Producing Factors) 

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

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

Analysis (EIA).

NTL Title Summary

2012-N06

Guidance to Owners and Operators 

of Offshore Facilities Seaward of the 

Coast Line Concerning Regional Oil 

Spill Response Plans

Provides clarification, guidance, and information for 

preparation of regional Oil Spill Response Plans. 

Recommends description of response strategy for worst 

case discharge (WCD) scenarios to ensure capability to 

respond to oil discharges is both efficient and effective.

2012-BSEE-G01 Marine Trash and Debris Awareness 

and Elimination

Instructs operators to exercise caution in the handling 

and disposal of small items and packaging materials; 

requires the posting of placards at prominent locations 

on offshore vessels and structures; and mandates a yearly 

marine trash and debris awareness training and 

certification process.

2012-JOINT-G01

Vessel Strike Avoidance and 

Injured/Dead Protected Species 

Reporting

Recommends protected species identification guides be 

carried on all Gulf of Mexico petroleum vessels and that 

vessel operators and crews maintain a vigilant watch for 

marine mammals. Vessels are to slow down or stop to 

avoid striking protected species, and operators are 

required to report sightings of any injured or dead 

protected species.

2011-JOINT-G01

Revisions to the List of OCS Blocks 

Requiring Archaeological Resource 

Surveys and Reports

Provides new information of which Outer Continental 

Shelf (OCS) blocks require archaeological surveys and 

reports and required survey line spacing in each block. 

This NTL augments NTL 2005-G07.
Table 1. (Continued).

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Environmental Impact Analysis for Initial Exploration Plan Page 4

NTL Title Summary

2010-N10

Statement of Compliance with 

Applicable Regulations and 

Evaluation of Information 

Demonstrating Adequate Spill 

Response and Well Containment 

Resources

Informs operators using subsea blowout preventers 

(BOPs) or surface BOPs on floating facilities that 

applications for well permits must include a statement 

signed by an authorized company official stating that the 

operator will conduct all activities in compliance with all 

applicable regulations, including the increased safety 

measures regulations (75 FR 63346). Informs operators 

that BOEM will be evaluating whether each operator has 

submitted adequate information demonstrating that it 

has access to and can deploy containment resources to 

promptly respond to a blowout or other loss of well 

control.

2010-N06

Information Requirements for 

Exploration Plans, Development and 

Production Plans, and Development 

Operations Coordination 

Documents on the OCS

Rescinds the limitations set forth in NTL 2008-G04 

regarding a blowout scenario and worst case discharge 

scenario, and provides guidance regarding the 

information required in blowout scenario and worst case 

discharge scenario descriptions.

2009-G40 Deepwater Benthic Communities

Guidance for avoiding and protecting high-density 

deepwater benthic communities (including 

chemosynthetic and deepwater coral communities) from 

damage caused by OCS oil and gas activities in water 

depths greater than 300 m (984 ft). Prescribes separation 

distances of 2,000 ft (610 m) from each mud and cuttings 

discharge location and 250 ft (76 m) from all other 

seafloor disturbances.

2009-G39 Biologically Sensitive Underwater 

Features and Areas

Guidance for avoiding and protecting biologically 

sensitive features and areas (i.e., topographic features, 

pinnacles, low relief live bottom areas, and other 

potentially sensitive biological features) when conducting 

OCS operations in water depths less than 300 m (984 ft) 

in the Gulf of Mexico.

2009-G06 Military Warning and Water Test 

Areas

Provides contact links to individual command 

headquarters for the military warning and water test 

areas in the Gulf of Mexico. Lease stipulations require 

lessees or designated operators to enter into an 

agreement with the appropriate individual military 

command headquarters concerning the control of 

electromagnetic emissions and use of boats and aircraft 

in the applicable warning area or water test area before 

commencing such traffic.

2008-G04

Information Requirements for 

Exploration Plans and Development 

Operations Coordination 

Documents

Guidance on the information requirements for OCS plans, 

including EIA requirements and information regarding 

compliance with the provisions of the Endangered 

Species Act and Marine Mammal Protection Act.

2005-G07 Archaeological Resource Surveys 

and Reports

Provides guidance on regulations regarding 

archaeological discoveries, specifies requirements for 

archaeological resource surveys and reports, and outlines 

options for protecting archaeological resources.
De Soto Canyon Block 178 March 2013

Environmental Impact Analysis for Initial Exploration Plan Page 5

A. Impact-Producing Factors

Table 2 is a matrix of impact-producing factors (IPFs) and potentially affected environmental 

resources adapted from Form BOEM-142. An "X" indicates that an IPF could reasonably be 

expected to affect a certain resource, and a dash (--) indicates no impact or negligible impact. 

Where there may be an effect, an analysis is provided in Section C. Potential IPFs for the 

proposed activity are listed below and briefly discussed in the following sections.

• Drilling rig presence (including noise 

and lights)

• Physical disturbance to the seafloor

• Air pollutant emissions

• Effluent discharges

• Water intake

• Onshore waste disposal

• Marine debris

• Support vessel and helicopter traffic

• Accidents

A.1 Drilling Rig Presence (including noise and lights)

The DP drillship Transocean Discoverer Deep Seas or an equivalent rig will be used for this 

project. The rig will be on site for approximately 120 days per well for drilling and temporary 

abandonment. Two supply boats and one crew vessel will be used during the drilling campaign. 

One offshore support vessel will be in the vicinity of the drilling rig at all times to provide 

assistance as necessary. The drillship has dimensions of 835 ft x 125 ft x 62 ft

(255 m x 38 m x 19 m) and an operating draft of 40 ft (12 m). The physical presence of a floating 

structure in the ocean can attract pelagic fishes and other marine life, as discussed in 

Section C.5.1.

DP drillships use a global positioning system (GPS), specific computer software, and sensors in 

conjunction with their own propellers and thrusters to maintain position. Essentially, through 

satellite navigation, the location of the vessel is precisely monitored and thrusters positioned at 

various locations about the vessel’s hull are activated to provide any required station-keeping 

adjustment. This allows operations at sea where mooring or anchoring is not feasible.

Drilling operations produce noise that includes strong tonal components at low frequencies, and 

in some cases infrasonic frequencies (MMS, 2000). Drilling noise from DP drillships is not 

particularly intense and is strongest at low frequencies, averaging 10 to 500 Hz (Richardson et 

al., 1995). From a drilling rig, sound and vibration paths to the water flow either through the air 

or through the risers (MMS, 2000). Drilling rigs also maintain exterior lighting for navigational 

and aviation safety in accordance with applicable Federal safety regulations.

A.2 Physical Disturbance to the Seafloor

In water depths of 600 m (1,969 ft) or greater, DP drillships disturb only a very small area of the 

seafloor around the wellbore (SHL) where the bottom template and blowout preventer (BOP) 

are located. Depending on the specific well configuration, this area is generally about 0.62 ac 

(0.25 ha) (MMS, 2007a).
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Environmental Impact Analysis for Initial Exploration Plan Page 6

Table 2. Matrix of impact-producing factors and affected environmental resources. X = potential impact; dash (--) = no impact or negligible impact.

Environmental Resources

Impact-producing Factors

Drilling Rig 

Presence (incl. 

noise & lights)

Physical 

Disturbance 

to Seafloor

Air 

Pollutant 

Emissions

Effluent 

Discharges

Water 

Intake

Onshore 

Waste 

Disposal

Marine 

Debris

Support 

Vessel/Helo 

Traffic

Accidents

Small Fuel 

Spill

Oil Spill 

(WCD)

Physical/Chemical Environment

Air quality and greenhouse gases -- -- --X(9) -- -- -- -- -- X(6) X(6)

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

Seafloor Habitats and Biota

Soft bottom benthic communities -- X -- X -- -- -- -- -- X(6)

High-density deepwater benthic communities -- --(4) -- --(4) -- -- -- -- -- X(6)

Designated topographic features -- --(1) -- --(1) -- -- -- -- -- --

Pinnacle trend area live bottoms -- --(2) -- --(2) -- -- -- -- -- --

Eastern Gulf live bottoms -- --(3) -- --(3) -- -- -- -- -- --

Threatened, Endangered, and Protected Species and Critical Habitat

Sperm whale (endangered) X(8) -- -- -- -- -- -- X(8) X(6,8) X(6,8)

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

Endangered mysticete whales -- -- -- -- -- -- -- -- -- --

Non-endangered marine mammals (protected) X -- -- -- -- -- -- X X(6) X(6)

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

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

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

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

Smalltooth sawfish (endangered) -- -- -- -- -- -- -- -- -- X(6)

Beach mice (endangered) -- -- -- -- -- -- -- -- -- X(6)

Elkhorn coral (endangered) -- -- -- -- -- -- -- -- -- X(6)

Coastal and Marine Birds

Marine birds X -- -- -- -- -- -- X X(6) X(6)

Shorebirds and coastal nesting birds -- -- -- -- -- -- -- X -- X(6)

Fisheries Resources

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

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

Archaeological Resources

Shipwreck sites -- --(7) -- -- -- -- -- -- -- X(6)

Prehistoric archaeological sites -- --(7) -- -- -- -- -- -- -- X(6)

Coastal Habitats and Protected Areas

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

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

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

Socioeconomic and Other Resources

Recreational and commercial fishing X -- -- -- -- -- -- -- X(6) X(6)

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

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

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

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

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

WCD = worst case discharge.
De Soto Canyon Block 178 March 2013

Environmental Impact Analysis for Initial Exploration Plan Page 7

Table 2 Footnotes and Applicability:

(1) Activities that may affect a marine sanctuary or topographic feature. Specifically, if the well, rig site, or any 

anchors will be on the seafloor within the following:

(a) 4-mi zone of the Flower Garden Banks, or the 3-mi zone of Stetson Bank;

(b) 1,000-m, 1-mi, or 3-mi zone of any topographic feature (submarine bank) protected by the Topographic 

Features Stipulation attached to an Outer Continental Shelf (OCS) lease;

(c) Essential Fish Habitat (EFH) criteria of 500 ft from any no-activity zone; or

(d) Proximity of any submarine bank (500-ft buffer zone) with relief greater than 2 m that is not protected by 

the Topographic Features Stipulation attached to an OCS lease.

• Not applicable. The lease is not within or near any marine sanctuary, topographic feature, or 

no-activity zone. There are no submarine banks in the blocks.

(2) Activities with any bottom disturbance within an OCS lease block protected through the Live Bottom 

(Pinnacle Trend) Stipulation attached to an OCS lease.

• The Live Bottom (Pinnacle Trend) Stipulation is not applicable to the lease area.

(3) Activities within any Eastern Gulf OCS block where seafloor habitats are protected by the Live Bottom 

(Low-Relief) Stipulation attached to an OCS lease. 

• The Live Bottom (Low-Relief) Stipulation applies to Eastern Gulf of Mexico Planning Area leases in water 

depths of 100 m (328 ft) or less; therefore, the lease is not covered by this stipulation. 

(4) Activities on blocks designated by the BOEM as being in water depths 300 m or greater.

• No impacts on high-density deepwater benthic communities are anticipated. There are no features 

indicative of high-density chemosynthetic communities or coral communities within 2,000 ft (610 m) of 

any drilling mud/cuttings discharge location. Because a dynamically positioned drillship will be used for 

drilling and completion, there will be no seafloor disturbances from the use of anchors.

(5) Exploration or production activities where H2S concentrations greater than 500 ppm might be encountered. 

• Not applicable. Based on data from nearby prospects in the De Soto Canyon Area, Murphy is requesting 

that BOEM classify the block as “H2S present.” An estimated H2S concentration of 0 to 40 ppm may be 

encountered while conducting proposed operations. Murphy will submit an H2S Contingency Plan to the 

appropriate BSEE Gulf of Mexico Region district office.

(6) All activities that could result in an accidental spill of produced liquid hydrocarbons or diesel fuel that you 

determine would impact these environmental resources. If the proposed action is located a sufficient distance 

from a resource that no impact would occur, the EIA can note that in a sentence or two.

• Accidental hydrocarbon spills could affect the resources marked (X) in the matrix, and impacts are 

analyzed in Section C.

(7) All activities that involve seafloor disturbances, including anchor emplacements, in any OCS block designated 

by the BOEM as having high-probability for the occurrence of shipwrecks or prehistoric sites, including such 

blocks that will be affected that are adjacent to the lease block in which your planned activity will occur. If the 

proposed activities are located a sufficient distance from a shipwreck or prehistoric site that no impact would 

occur, the EIA can note that in a sentence or two.

• No impacts on archaeological resources are expected. The lease area is not on the list of archaeology 

survey blocks (BOEM, 2012d) and is well beyond the 60-m (197-ft) depth contour used by the BOEM as 

the seaward extent for prehistoric archaeological site potential in the Gulf of Mexico. Murphy 

commissioned an Archaeological Assessment of the block and no evidence of any shipwrecks or 

historically significant artifacts was observed. Because a dynamically positioned drillship will be used for 

drilling, there will be no seafloor disturbances from the use of anchors.

(8) All activities that you determine might have an adverse effect on endangered or threatened marine mammals 

or sea turtles or their critical habitats. 

• IPFs that may affect marine mammals, sea turtles, or their critical habitats include drilling rig presence, 

support vessel and helicopter traffic, and accidents. See Section C.

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

• Not applicable.
De Soto Canyon Block 178 March 2013

Environmental Impact Analysis for Initial Exploration Plan Page 8

A.3 Air Pollutant Emissions

Air pollutant emissions are calculated in EP Attachment O and are estimated to be insignificant. 

Offshore air pollutant emissions will result from drilling rig operations, as well as service vessels 

and helicopters. These emissions occur mainly from combustion of diesel fuel. The combustion 

of fuels occurs on diesel-powered generators, pumps, or motors and from lighter fuel motors. 

Primary air pollutants typically associated with OCS activities are suspended particulate matter 

(PM), sulfur oxides (SOx), nitrogen oxides (NOx), volatile organic compounds (VOCs), and carbon 

monoxide (CO).

The Air Quality Emissions Report prepared in accordance with BOEM requirements 

demonstrates that the projected emissions are below exemption levels set by the applicable 

regulations in 30 CFR 550.302-304. Therefore, no control measures are required and no 

significant onshore impacts are expected.

A.4 Effluent Discharges

Effluent discharges are summarized in EP Attachment N. All offshore discharges will be in 

accordance with requirements of the National Pollutant Discharge Elimination System (NPDES) 

General Permit No. GEG460000 issued by the U.S. Environmental Protection Agency (USEPA). 

Discharges will be in compliance with the permit terms and monitored as required by the 

permit.

For each well, an estimated 12,000 bbl of water-based drilling muds and 2,430 bbl of cuttings 

coated with water-based drilling muds will be released at the seafloor during the initial well 

intervals before the marine riser is set that allows returns to the surface. Excess cement slurry 

will also be released at the seafloor during casing installation for the riserless portion of the 

drilling operations.

A synthetic-based mud (SBM) system will be used after the riser is installed. The SBM will not be 

discharged but will be recovered and transported to the shorebase for recycling by the mud 

company. Treated SBM cuttings will be discharged overboard after treatment with a cuttings 

dryer, which is expected to reduce retention on cuttings in accordance with the NPDES permit 

requirement. The volume of treated SBM cuttings to be discharged per well is estimated to be 

3,700 bbl.

Other effluent discharges in accordance with the NPDES permit will include excess cement, 

non-contact cooling water, treated sanitary and domestic wastes, deck drainage, desalination 

unit brine, uncontaminated freshwater and seawater, and ballast water.

A.5 Water Intake

Seawater will be drawn from the ocean for once-through, non-contact cooling of machinery on 

the drilling rig. The estimated intake and discharge of cooling water is 2,969.4 million gallons

(70.7 million bbl) per well. 

Section 316(b) of the Clean Water Act requires NPDES permits to ensure that the location, 

design, construction, and capacity of cooling water intake structures reflect the best technology 

available to minimize adverse environmental impact from impingement and entrainment of 

aquatic organisms. The current NPDES General Permit No. GEG460000 does not specify 
De Soto Canyon Block 178 March 2013

Environmental Impact Analysis for Initial Exploration Plan Page 9

requirements for existing facilities (those that started construction before 16 July 2006), which 

includes the Transocean Discoverer Deep Seas. The DP drilling vessel ultimately selected for this 

project will be in compliance with all cooling water intake structure requirements.

A.6 Onshore Waste Disposal

Solid and liquid wastes generated during drilling are tabulated in EP Attachment N. An 

estimated total of 1,000 ft3

(28 m3) of trash and debris will be transported to the shorebase for 

disposal at Newpark Environmental in Port Fourchon, Louisiana. An estimated 5,000 bbl/well of 

spent SBM drilling fluids and cuttings will be transported in cuttings boxes on supply boats to 

the shorebase and trucked to Newpark Environmental for disposal.

A.7 Marine Debris

Murphy will comply with all regulations relating to solid wastes handling and disposal, including 

the International Convention for the Prevention of Pollution from Ships (MARPOL 73/78) 

Annex V requirements and USEPA and U.S. Coast Guard (USCG) regulations, as well as those of 

the BOEM. For example, BOEM regulations at 30 CFR 250.300(a) and (b)(6) prohibit operators 

from deliberately discharging containers and other similar materials (i.e., trash and debris) into 

the marine environment, and 30 CFR 250.300(c) requires durable identification markings on 

equipment, tools, and containers (especially drums), and other material. USEPA and USCG 

regulations require operators to become proactive in avoiding accidental loss of solid waste 

items by developing waste management plans, posting informational placards, manifesting trash 

sent to shore, and using special precautions such as covering outside trash bins to prevent 

accidental loss of solid waste. In addition to the regulations in 30 CFR 250, BSEE issued 

NTL 2012-BSEE-G01, which instructs operators to exercise caution in the handling and disposal 

of small items and packaging materials, requires the posting of placards at prominent locations 

on offshore vessels and structures, and mandates a yearly marine trash and debris awareness 

training and certification process.

A.8 Support Vessel and Helicopter Traffic

Murphy will use existing shorebase facilities at Port Fourchon, Louisiana, for onshore support for 

vessel activities. Air transportation (helicopters) will be based at facilities in Galliano, Louisiana. 

No terminal expansion or construction is planned at either location.

The project will be supported by one crew boat and two supply vessels traveling between the 

drilling rig and the onshore support base. The crew boat will make one round trip per week, and 

the supply vessels will make two round trips per week. Typically, the boats will move to the 

project area via the most direct route from the shorebase.

A helicopter will make round-trips per week between the drilling rig and the heliport as 

necessary. The helicopter will be used to transport personnel and small supplies and will 

normally take the most direct route of travel between the shorebase and the lease area when 

air traffic and weather conditions permit. Helicopters typically maintain a minimum altitude of 

700 ft (213 m) while in transit offshore, 1,000 ft (305 m) over unpopulated areas or across 

coastlines, and 2,000 ft (610 m) over populated areas and sensitive habitats such as wildlife 

refuges and park properties. Additional guidelines and regulations specify that helicopters 

maintain an altitude of 1,000 ft (305 m) within 300 ft (91 m) of marine mammals (BOEM, 2012a).
De Soto Canyon Block 178 March 2013

Environmental Impact Analysis for Initial Exploration Plan Page 10

A.9 Accidents

A.9.1 Types of Accidents Evaluated

The analysis in this EIA focuses on two potential accidents:

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

• the worst case discharge (WCD) for this Initial EP, which is an oil spill resulting from an 

uncontrolled blowout.

The following subsections summarize assumptions about the sizes and fates of these spills, as 

well as Murphy’s spill response plans. Impacts are analyzed in Section C.

MMS (2007b) and BOEM (2012b) analyzed other types of accidents including: chemical spills, 

vessel collisions, and loss of well control. These types of accidents, along with an SBM spill from 

a riser disconnect and a hydrogen sulfide (H2S) release, are discussed briefly in Section A.9.4.

A.9.2 Small Fuel Spill

Spill Size. According to the analyses in MMS (2007b) and BOEM (2012b), the most likely type of 

small spill (<1,000 bbl) as a result of OCS activities is a minor diesel fuel spill. Historically, most 

diesel spills have been ≤1 bbl, and this size is predicted to be the most common in ongoing and 

future OCS activities in the Western and Central Gulf of Mexico Planning Areas. As the spill size 

increases, the incident rate declines dramatically (MMS, 2007b; BOEM, 2012c). The median size 

for spills ≤1 bbl is 0.024 bbl, and the median size for spills of 1 to 10 bbl is 3 bbl (BOEM, 2012b). 

For this analysis, a small diesel fuel spill of 3 bbl is assumed. Operational experience suggests 

that the most likely cause of such a spill would be a hose rupture resulting in the loss of the 

contents of a fuel transfer hose, which is less than 3 bbl.

Spill Fate. The fate of a small fuel spill in the lease area would depend on meteorological and 

oceanographic conditions at the time, as well as the effectiveness of spill response activities. 

However, given the open ocean location of the lease area and response actions, it is expected 

that impacts from a small spill would be minimal (BOEM, 2012c).

The water-soluble fractions of diesel are dominated by two- and three-ringed polycyclic 

aromatic hydrocarbons (PAHs), which are moderately volatile (National Research Council, 2003). 

The constituents of these oils are light to intermediate in molecular weight and can be readily 

degraded by aerobic microbial oxidation. Due to its light density, diesel will not sink to the 

seafloor. Diesel dispersed in the water column can adhere to suspended sediments, but this 

generally occurs only in coastal areas with high suspended solids loads (National Research 

Council, 2003) and would not be expected to occur to any appreciable degree in offshore waters 

of the Gulf of Mexico. Diesel oil is readily and completely degraded by naturally occurring 

microbes (National Oceanic and Atmospheric Administration [NOAA], 2006).

For purposes of this EIA, the fate of a small diesel fuel spill was estimated using NOAA’s 

Automated Data Inquiry for Oil Spills 2 (ADIOS2) model. This model uses the physical properties 

of oils in its database to predict the rate of evaporation and dispersion over time, as well as 

changes in the density, viscosity, and water content of the product spilled. It is estimated that 

over 90% of a small diesel spill would be evaporated or dispersed within 24 hours. The area of 
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the sea surface with diesel fuel on it during this 24-hour period would range from 1.2 to 12 ac 

(0.5 to 5 ha), depending on sea state and weather conditions.

The ADIOS2 results, coupled with spill trajectory information discussed below for a large spill,

indicate that a small fuel spill would not have any impacts on coastal or shoreline resources. 

The lease area is approximately 75 miles (121 km) from the nearest shoreline (Louisiana). 

Modeling results discussed below indicate that a spill in the lease area will contact shorelines

from Texas to Florida within 120 days with various probabilities during different seasons (see 

Section A.9.3). Shorter time periods result in lower probabilities of contact. By those times, 

essentially 100% of a small fuel spill would have been dispersed or evaporated by natural 

processes, without taking into account Murphy’s response measures. MMS (2007b) similarly 

concluded that spills <1,000 bbl are not expected to persist as a slick on the surface of the water 

beyond a few days and are unlikely to make landfall or reach coastal waters prior to breaking 

up. MMS (2007b) noted that this conclusion is supported by a previous analysis of three-day 

trajectory model runs, previous weathering analyses, and historical records of spill incidents.

Spill Response. In the unlikely event the shipboard prevention procedures fail to prevent a fuel 

spill, response equipment and trained personnel would be activated so that any spill effects 

would be localized and would result only in short-term environmental consequences. 

EP Attachment Q provides a detailed discussion of Murphy’s response to a spill.

A.9.3 Crude Oil Spill (Worst Case Discharge)

Spill Size. In accordance with requirements of NTL 2010-N06, Murphy has estimated a WCD for 

this EP as 394,475 barrels of oil per day (BOPD). The maximum total volume during a blowout 

could potentially be 6.496 million barrels of oil (MMBO), assuming no source 

control/containment intervention and reduction. The detailed analysis of this calculation can be 

found in EP Attachment P.

Historically, blowouts are rare events and most do not result in oil spills. Holand (1997) 

estimated a probability of 0.0021 for a deep drilling blowout during exploration drilling based on 

U.S. Gulf of Mexico data. An updated analysis using the SINTEF database estimates a blowout 

frequency of 0.0017 per exploratory well for non-North Sea locations (International Association 

of Oil & Gas Producers, 2010). As noted by MMS (2007b), from 1992 to 2005, half of blowouts 

lasted less than half a day, and fewer than 10% of blowouts resulted in spilled oil. BOEM is in 

the process of updating these spill frequency estimates to include the recent Macondo event; 

however, significant changes to the spill rates for the entire OCS are not anticipated (BOEM, 

2012a). As noted in the Introduction, the baseline risk of a catastrophic blowout is estimated to 

be once every 26 years (BSEE Final Drilling Safety Rule, 75 FR 63365).

Murphy will drill to the objective sands outlined in the EP utilizing a typical structural, 

conductor, surface, and production casing program. If mandated by wellbore conditions, an 

intermediate casing string will be set prior to drilling through the objective sand. In the event of 

a blowout during the course of drilling an open hole in the objective sands, Murphy would 

immediately activate its Sub-Regional Oil Spill Response Plan and Spill Management Team to 

initiate recovery of liquid hydrocarbons on the receiving water and review potential well 

intervention options as detailed in their Well Containment Plan which will be approved 

separately prior to initiating operations under this EP. Murphy will comply with NTL 2010-N10 

and the Final Drilling Safety Rule, which specifies additional safety measures for OCS activities.
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Spill Trajectory. The fate of a large oil spill in the lease area would depend on meteorological 

and oceanographic conditions at the time. The Oil Spill Risk Analysis (OSRA) model is a 

computer simulation of oil spill transport that uses realistic data for winds and currents to 

predict spill fate. Although this model has received some criticism recently (Earthjustice, 2011), 

it is still the most widely scientifically accepted model for estimating the fate of small fuel spills. 

The primary criticism of the OSRA model results as provided in Ji et al. (2004) was that the 

model did not evaluate the fate of a spill over time periods longer than 30 days, nor did it 

predict the fate of a release that continues over a period of weeks or months, as in the Macondo 

incident. Also as noted by Ji et al. (2004), the OSRA model does not take into account the 

chemical composition or biological weathering of oil spills, the spreading and splitting of oil 

spills, or spill response activities. The model does not assume a particular spill size but has 

generally been used by the BOEM to evaluate contact probabilities for spills greater than 

1,000 bbl.

To address this criticism, a special OSRA run was conducted for the recent BOEM Western and 

Central Gulf of Mexico Planning Area Supplemental EISs (BOEM, 2012c) in order to estimate the 

impacts of a possible future catastrophic long-duration oil spill. In this OSRA model run a 

hypothetical high volume, long-duration oil spill was assumed to have occurred, and the analysis 

emphasized modeling a spill that continued for 90 consecutive days, with each trajectory 

tracked for up to 120 days.

The OSRA model run for this revised analysis was conducted for five hypothetical launch points 

in the Central and Western Gulf of Mexico Planning Areas. These launch points were 

deliberately located in areas identified as having a high possibility of containing large oil 

reserves.

The five launch point areas were as follows:

1. Central Gulf of Mexico shelf area west of the Mississippi River (28.98660° N latitude, 92.17851° W 

longitude);

2. Central Gulf of Mexico shelf area east of the Mississippi River (29.91388° N latitude, 88.15338° W 

longitude);

3. Central Gulf of Mexico slope area (27.31998° N latitude, 90.22203° W longitude);

4. Western Gulf of Mexico shelf area (27.55423° N latitude, 96.76627° W longitude); and

5. Western Gulf of Mexico slope area (27.51367° N latitude, 94.51836° W longitude).

The results for Launch Point 2, the launch point nearest to the project area, are presented in 

Table 3.

OSRA is a preliminary risk assessment model. In the event of an actual oil spill, real-time 

monitoring and trajectory modeling would be conducted using current and wind data available 

from the rigs and permanent production structures in the area. Satellite and aerial monitoring 

of the plume and real-time trajectory modeling using wind and current data would continue on 

a daily basis to help position equipment and human resources throughout the duration of any 

major spill or uncontrolled release.
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Table 3. Conditional probabilities expressed as percent chance that an oil spill starting at 

Launch Point 2 will contact a certain parish, county, or coastline within 120 days

(Modified from: BOEM, 2012c, Appendix C).

Season Winter Spring Summer Fall

Day 3 10 30 120 3 10 30 120 3 10 30 120 3 10 30 120

County or Parish Percent Chance

Cameron, Texas -- -- -- -- -- -- -- -- -- -- -- 1 -- -- -- --

Willacy, Texas -- -- -- -- -- -- -- -- -- -- -- 1 -- -- -- --

Kenedy, Texas -- -- -- 1 -- -- -- -- -- -- -- -- -- -- -- 1

Kleberg, Texas -- -- -- 1 -- -- -- -- -- -- -- -- -- -- -- --

Calhoun, Texas -- -- -- 1 -- -- -- -- -- -- -- -- -- -- -- 1

Matagorda, Texas -- -- -- 2 -- -- -- -- -- -- -- 1 -- -- -- 2

Brazoria, Texas -- -- -- 1 -- -- -- -- -- -- -- -- -- -- -- 1

Galveston, Texas -- -- -- 1 -- -- -- -- -- -- -- 1 -- -- -- --

Jefferson, Texas -- -- -- 1 -- -- -- -- -- -- -- -- -- -- -- --

Cameron, Louisiana -- -- -- 1 -- -- -- -- -- -- -- -- -- -- -- --

Vermilion, Louisiana -- -- -- 2 -- -- -- -- -- -- -- -- -- -- -- --

Terrebonne, Louisiana -- -- 3 4 -- -- -- -- -- -- -- 1 -- -- -- 1

Lafourche, Louisiana -- -- -- 1 -- -- -- -- -- -- -- -- -- -- 1 1

Jefferson, Louisiana -- -- -- -- -- -- -- -- -- -- -- 1 -- -- 1 1

Plaquemines, Louisiana 1 14 21 23 -- 3 4 6 1 8 20 25 2 21 27 28

St. Bernard, Louisiana -- 4 5 5 -- 1 2 3 1 7 14 16 -- 8 9 10

Hancock, Mississippi -- 1 2 4 -- 2 2 2 -- 2 3 3 1 3 5 5

Harrison, Mississippi 2 3 4 5 -- 4 4 4 1 3 4 4 1 2 3 3

Jackson, Mississippi 7 11 11 13 5 11 12 12 1 3 4 4 6 12 13 14

Mobile, Alabama 11 14 14 15 11 16 17 17 4 8 9 10 8 11 12 13

Baldwin, Alabama 4 7 7 9 6 14 16 17 1 8 10 10 1 2 2 3

Escambia, Florida -- 1 1 2 1 5 11 13 1 3 5 6 -- -- 1 1

Okaloosa, Florida -- -- -- 1 -- 1 2 3 -- -- 1 1 -- -- -- --

Walton, Florida -- -- -- -- -- 1 1 1 -- -- -- -- -- -- -- 1

Bay, Florida -- -- -- 1 -- 2 3 5 -- -- 1 2 -- -- -- --

Gulf, Florida -- -- -- -- -- 1 3 5 -- -- 1 1 -- -- -- --

Franklin, Florida -- -- -- -- -- -- -- 3 -- -- 1 2 -- -- -- --

Wakulla, Florida -- -- -- -- -- -- -- 1 -- -- -- -- -- -- -- --

Taylor, Florida -- -- -- -- -- -- -- 1 -- -- -- -- -- -- -- --

Levy, Florida -- -- -- -- -- -- -- 1 -- -- -- -- -- -- -- --

Monroe, Florida -- -- -- 1 -- -- -- 1 -- -- -- -- -- -- -- --

Dade, Florida -- -- -- -- -- -- -- 1 -- -- -- -- -- -- -- --

"--" = Values <1.0%. Areas where there is <0.5% chance of contact within 120 days are not shown.

Weathering. Following an oil spill, several physical, chemical, and biological processes, 

collectively called weathering, interact to change the physical and chemical properties of the oil, 

influencing potential effects to marine organisms and ecosystems. The most important 

weathering processes include spreading, evaporation, dissolution, dispersion into the water 

column, formation of water-in-oil emulsions, photochemical oxidation, microbial degradation, 

adsorption to suspended PM, and stranding on shore or sedimentation to the seafloor (National 

Research Council, 2003).

Weathering decreases the concentration of oil and produces changes in its chemical 

composition, physical properties, and toxicity. The more toxic, light aromatic and aliphatic 

hydrocarbons are lost rapidly by evaporation and dissolution from a slick on the water surface. 

Evaporated hydrocarbons are degraded rapidly by sunlight. Biodegradation of oil on the water 

surface and in the water column by marine bacteria removes first the n-alkanes and then the 
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light aromatics from the oil. Other petroleum components are biodegraded more slowly. 

Photo-oxidation attacks mainly the medium and high molecular weight PAHs in the oil on the 

water surface.

Spill Response. BOEM has issued recent NTLs following the Macondo spill that clarify additional 

oil-spill prevention and response planning requirements. These NTLs are summarized in Table 2,

and additional BOEM (2012b) guidance is provided below.

NTL 2012-N06 – Guidance to Owners and Operators of Offshore Facilities Seaward of the 

Coast Line Concerning Regional Oil Spill Response Plans: This NTL, effective 10 August 2012, 

provides clarification, guidance, and information on the preparation and submittal of 

regional OSRPs for owners and operators of oil handling, storage, or transportation facilities, 

inclusive of pipelines, located seaward of the coastline. It states that lessees, designated 

operators, and pipeline right-of-way holders are responsible for preparation and submission 

of these plans. Some of the clarifications and recommended practices in the NTL are based 

on lessons learned from the Macondo oil spill response.

NTL 2010-N10 – Statement of Compliance with Applicable Regulations and Evaluation of 

Information Demonstrating Adequate Spill Response and Well Containment Resources: 

This NTL, effective 8 November 2010, applies only to operators conducting operations using 

subsea or surface BOPs on floating facilities. It requires that lessees and operators must 

submit a statement signed by an authorized company official with each well permit 

application indicating that they will conduct all of their authorized activities in compliance 

with all applicable regulations, including the Increased Safety Measures Regulations at 

75 FR 63346. The NTL also informs lessees that the Bureau of Ocean Energy Management, 

Regulation and Enforcement (BOEMRE) will evaluate whether the operator has submitted 

adequate information demonstrating that it has access to and can deploy surface and 

subsea containment resources that would be adequate to promptly respond to a blowout or 

other loss of well control. The NTL notifies the operator that BOEMRE intends to evaluate 

the adequacy of each operator to comply in the operator’s current OSRP; therefore, there is 

an incentive for voluntary compliance.

NTL 2010-N06 – Information Requirements for Exploration Plans, Development and 

Production Plans, and Development Operations Coordination Documents on the OCS:

This NTL, effective 18 June 2010, explains the procedures for the lessee or operator to 

submit supplemental information for new or previously submitted EPs, Development and 

Production Plans, or Development Operations Coordination Documents. The required 

supplemental information includes the following: (1) a description of the blowout scenario 

as required by 30 CFR 250.213(g) or 30 CFR 250.243(h); (2) a description of their 

assumptions and calculations used in determining the volume of the WCD required by 

30 CFR 250.219 or 30 CFR 250.250; and (3) a description of the measures proposed that 

would enhance the ability to prevent a blowout, to reduce the likelihood of a blowout, and 

to conduct effective and early intervention in the event of a blowout, including the 

arrangements for drilling relief wells and any other measures proposed. The early 

intervention methods of the third requirement could actually include the surface and subsea 

containment resources that BOEM announced in NTL 2010-N10, which states that BOEM 

will review to ensure that the measures are adequate to promptly respond to a blowout or 

other loss of well control.
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EP Attachment Q provides a detailed description of Murphy’s site-specific response to the worst 

case spill for this plan. These sections, along with Murphy’s Oil Spill Response Plan (OSRP), also 

include a description of surface and subsea containment capabilities that could be implemented 

in the event of the worst case spill for this plan.

Oil spill response-related activities for facilities included in the EP will incorporate the state of

Florida; Murphy has a Sub-Regional OSRP that was approved in August 2011 with a more recent 

modification of July 2012 awaiting approval. Murphy will be demonstrating oil spill financial 

responsibility for the facilities proposed in this EP according to 30 CFR Part 254 and 

NTL 2008-N05, “Guidelines for Oil Spill Financial Responsibility for Covered Facilities.”

A.9.4 Other Accidents Not Analyzed in Detail

MMS (2007b) and BOEM (2012b) discuss other types of accidents including: chemical spills, 

vessel collisions, and loss of well control. The information from the EIS on these topics remains 

valid and is incorporated by reference into this document. These accidents are discussed briefly 

below along with a SBM spill from a riser disconnect and a H2S release. There are no other 

site-specific issues for the drilling of the wells proposed in this EP.

Chemical Spills. Chemicals are stored and used to condition drill muds and during production 

and in well completions, stimulation, and workover procedures. The relative quantity of their 

use is reflected in the largest volumes spilled. Completion fluids are the largest quantity used 

and comprise the largest releases. Between 5 and 15 chemical spills are anticipated each year, 

with the majority being <50 bbl in size. The most common chemicals spilled are methanol, 

ethylene glycol, and zinc bromide. Additional production chemicals are needed in deepwater 

operations where gas hydrates tend to form. Spill volumes are anticipated to remain about the 

same, but spill frequency can be expected to decrease because of advances in subsea processing 

(BOEM, 2012c).

Riser Disconnect SBM Spills. In deepwater drilling, SBMs are preferred over petroleum oil-based 

muds (OBMs) due to the superior environmental properties of SBMs. The synthetic base fluids

used in SBMs are less toxic to the marine environment and have the potential to biodegrade. 

SBMs have been used in the Gulf of Mexico since the mid-1990s, and between 5 and 20 SBM 

releases are anticipated each year as a result of offshore drilling programs. The majority of 

these releases are <50 bbl in size, but accidental riser disconnects may result in the release of 

medium (238 to 2,380 bbl) to large (>2,381 bbl) quantities of drilling fluids. Riser disconnect 

accidents are of particular concern when SBMs are in use (BOEM, 2013a).

Vessel Collisions. BOEM data show that from 1996 to 2009 there were 226 OCS-related 

collisions. Most collision mishaps are the result of service vessels colliding with platforms or 

vessel collisions with pipeline risers. Approximately 10% of vessel collisions with platforms in 

the OCS resulted in diesel spills, and in several collision incidents, fires resulted from 

hydrocarbon releases. To date, the largest diesel spill associated with a collision occurred in 

1979 when an anchor-handling boat collided with a drilling platform in the Main Pass lease area, 

spilling 1,500 bbl. Diesel fuel is the product most frequently spilled, but oil, natural gas, 

corrosion inhibitor, hydraulic fluid, and lube oil have also been released as the result of vessel 

collisions. Human error accounted for approximately half of all reported vessel collisions from 

2006 to 2009. As summarized in MMS (2007b) and BOEM (2012b), vessel collisions occasionally 

occur during routine operations. Some of these collisions have caused spills of diesel fuel or 
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chemicals. Murphy will comply with all USCG- and BOEM-mandated safety requirements to 

minimize the potential for vessel collisions.

Loss of Well Control. A loss of well control is the uncontrolled flow of a reservoir fluid that may 

result in the release of gas, condensate, oil, drilling fluids, sand, or water. Loss of well control is 

a broad term that includes very minor up to the most serious well control incidents, while 

blowouts are considered to be a subset of more serious incidents with greater risk of oil spill or 

human injury (MMS, 2007b). Loss of well control may result in the release of synthetic drilling 

fluid or loss of oil. Murphy has a robust system in place to prevent loss of well control. 

Measures to prevent a blowout, reduce the likelihood of a blowout, and conduct effective and 

early intervention in the event of a blowout are described in the NTL 2010-06 package 

submitted with the exploration plan, as required. The potential for a loss-of-well-control event 

will be minimized by adhering to the requirements of applicable regulations such as the 

Final Drilling Safety Rule and NTL 2010-N10, which specify additional safety measures for 

OCS activities.

H2S Release. Based on data from nearby prospects in the De Soto Canyon Area, an estimated 

H2S concentration of 0 to 40 ppm may be encountered while conducting the proposed 

operations. Murphy does not anticipate encountering H2S concentrations greater than 

500 ppm, therefore a Modeling Plan is not required per NTL 2008-04. In accordance with 

Title 30 CFR 250.490(f), Murphy will submit an H2S Contingency Plan to the appropriate BSEE 

Gulf of Mexico Region district office. Murphy will request that DC 178 be classified by the BOEM

as an area where the presence of H2S has been confirmed. Based on this, no further discussion 

of H2S is warranted.

B. Affected Environment

The lease area is on the continental slope in the central Gulf of Mexico, 75 miles (121 km) from 

the nearest shoreline (Louisiana), and 145 miles (233 km) from the onshore support base at Port 

Fourchon, Louisiana (Figure 1). The lease area, located west of the Florida Escarpment, is 

approximately 50 miles (80 km) southeast of the continental shelf edge within a region 

punctuated by numerous submarine canyon features (Geoscience Earth & Marine Services, Inc. 

[GEMS], 2013). Figure 2 shows the bathymetry and location of DC 178 in the Central Gulf of 

Mexico Planning Area.

Water depths at the wellsites range from approximately 6,567 to 6,580 ft (2,002 to 2,006 m). 

There is no evidence of significant seafloor or subsurface faulting, fluid expulsion features, or 

high-density deepwater benthic communities near the wellsites and the potentials for shallow 

water flow and shallow gas vary from negligible to low (GEMS, 2013).
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Figure 2. Bathymetric map of the lease area showing the surface hole locations of Wells "A", "B," and 

"C" in De Soto Canyon Block 178.
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A detailed description of the regional affected environment, including meteorology, 

oceanography, geology, air and water quality, benthic communities, threatened and 

endangered species, biologically sensitive resources, archaeological resources, socioeconomic 

conditions, and other marine uses is provided in recent lease sale EISs (MMS, 2007b, 2003; 

BOEM, 2012b). These regional descriptions remain valid and are incorporated by reference. 

General background information is presented below, and brief descriptions of each potentially 

affected resource, including site-specific and/or new information if available, are presented in 

Section C.

The Macondo spill resulted in impacts to water quality in the area of the spill. In addition to the 

oil slick on the sea surface, plumes of submerged oil droplets were produced when subsea 

dispersants were applied at the wellhead (Camilli et al., 2010; Hazen et al., 2010; Joint Analysis 

Group, 2010a,b,c). Despite limited information on the water quality of deep water, it is clear 

that conditions in the offshore waters of the Gulf of Mexico were altered by the Macondo event. 

Various monitoring efforts and environmental studies are in progress, but it is not currently 

possible to precisely estimate the long-term impacts the spill will have on offshore water quality

(BOEM, 2012b).

The lease area is located approximately 33 miles (53 km) east of the Macondo spill site. Based 

on an analysis of satellite imagery, the surface slick extended over the lease area and there is 

the possibility that water quality in the lease area was briefly affected. Prior to the Macondo 

incident, water quality in deep, offshore waters of the Gulf of Mexico was expected to be good,

with low levels of contaminants (Kennicutt, 2000). Based on the information currently available, 

there is no reason to expect any long-term change in water quality conditions in the lease area 

from those predicted in the recent lease sale EISs (MMS, 2007b, 2003; BOEM, 2012b,c).

C. Impact Analysis

This section analyzes the potential direct and indirect impacts of routine activities and accidents. 

Impacts have been analyzed extensively in recent lease sale EISs for the Eastern, Central, and 

Western Gulf of Mexico Planning Areas (MMS, 2007b; BOEM, 2012b,c) as well as the 

Environmental Assessment for Gulf of Mexico deepwater operations and activities (MMS, 2000)

and the EIS for deepwater Grid 18 where the lease area is located (MMS, 2003). The 

information in these documents is incorporated by reference. Potential site-specific issues are 

addressed in this section.

C.1 Physical/Chemical Environment

C.1.1 Air Quality

There are no site-specific air quality data for the project area. Because of the distance from 

shore-based pollution sources and the lack of sources offshore, air quality at the wellsites is 

expected to be good. The attainment status of Federal OCS waters is unclassified because there 

is no provision in the Clean Air Act for classification of areas outside State waters (MMS, 2007b).

In general, ambient air quality on coastal counties along the Gulf of Mexico is relatively good 

(BOEM, 2012a). As of December 14, 2012, Louisiana, Mississippi, Alabama, and Florida coastal 
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counties and parishes are in attainment of the National Ambient Air Quality Standards (NAAQS) 

for all criteria pollutants (USEPA, 2012). One coastal metropolitan area in Texas 

(Houston-Galveston-Brazoria) is a nonattainment area for 8-hour ozone.

As noted earlier, based on calculations made pursuant to applicable regulations, emissions from 

drilling activities are not expected to be significant as they are below exemption levels. 

Therefore, the only potential effects to air quality would be from routine air pollutant emissions, 

a small fuel spill, and a large oil spill (WCD).

BOEM has reexamined the analysis for air quality presented in MMS (2007b) based on 

additional information and in consideration of the Macondo oil spill event. No substantial new 

information was found that would alter the potential impacts on air quality presented in 

previous lease sale EISs (BOEM, 2012c).

Impacts of Air Pollutant Emissions

Air pollutant emissions are the only routine IPF likely to affect air quality. Offshore air pollutant 

emissions will result from the drilling rig operations and helicopters and service vessels. These 

emissions occur mainly from combustion or burning of diesel fuel. The combustion of fuels 

occurs primarily on diesel-powered generators, pumps, or motors and from lighter fuel motors. 

Primary air pollutants typically associated with OCS activities are suspended PM, SOx, NOx, VOCs, 

and CO. Emissions of pollutants into the atmosphere from these activities are not projected to 

have significant effects on onshore air quality because of the prevailing atmospheric conditions, 

emission rates and heights, and resulting pollutant concentrations. As described in previous 

lease sale EISs, the incremental contribution to cumulative impacts from activities similar to 

Murphy’s proposed activities is not significant and will not cause or contribute to a violation of 

any NAAQS (MMS, 2007b; BOEM, 2012b). Since the BOEM completed the lease sale EISs, the 

USEPA has adopted a new short-term NAAQS for nitrogen dioxide (NO2). The standard has not 

yet been implemented in the Gulf Coast states, but given the levels of expected emissions and

the distance of the project from shore, emissions from the activities described in Murphy’s 

proposed EP are not likely to contribute to violations of any NAAQS onshore.

Carbon dioxide (CO2) and methane (CH4) emissions from the project would constitute a small 

incremental contribution to greenhouse gas (GHG) emissions from all OCS activities. According 

to the Final Programmatic EIS (BOEM, 2012a), estimated CO2 emissions from all OCS activities in 

the 2012 leasing program are about 0.025% to 0.049% of the global CO2 emissions from fossil 

fuel combustion and GHG emissions are about 0.0046% to 0.0078% of the total global GHG 

emissions. GHG emissions may contribute to climate change, with important effects on 

temperature, rainfall, frequency of severe weather, ocean acidification, and sea level rise 

(Intergovernmental Panel on Climate Change, 2007). GHG emissions from this proposed project 

represent a negligible contribution to the total GHG emissions from reasonably foreseeable 

activities in the Gulf of Mexico area and would not significantly alter any of the climate change 

impacts evaluated in the lease sale EIS (MMS, 2007b) or Final Programmatic EIS (BOEM, 2012a).

Because of the distance from shore, routine operations in the project area are not expected to 

have any impact on air quality conditions along the coast, including nonattainment areas. 

As noted in the Final Programmatic EIS (BOEM, 2012a), emissions of air pollutants from routine 

activities in the Central Gulf of Mexico Planning Area are projected to have minimal impacts to 

onshore air quality because of the prevailing atmospheric conditions, emission heights, emission 
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rates, and the distance of these emissions from the coastline. The Air Quality Emissions Report 

(see EP Attachment O) prepared in accordance with BOEM requirements shows that the 

projected emissions are below exemption levels; therefore, according to 30 CFR 550.303, the 

emissions will not significantly affect the air quality of the onshore area for any of the criteria 

pollutants. No further analysis or control measures are required.

The Breton Wilderness Area, which is part of the Breton National Wildlife Refuge (NWR), is 

designated under the Clean Air Act as a Prevention of Significant Deterioration (PSD) Class I air 

quality area. The BOEM is required to notify the National Park Service (NPS) and U.S. Fish and 

Wildlife Service (USFWS) if emissions from proposed projects may affect the Breton Class I area.

Additional review and mitigation measures may be required for sources within 186 miles 

(300 km) of the Breton Class I area that exceed emission limits agreed upon by the administering 

agencies (NPS, 2010). The lease area is approximately 90 miles (145 km) from the 

Breton Wilderness Area, therefore additional modeling may be necessary. Murphy will comply 

with all BOEM requirements regarding air emissions including consultation with the Federal 

Land Manager, if necessary.

Impacts of a Small Fuel Spill

Potential impacts of a small spill on air quality are expected to be consistent with those analyzed 

and discussed in EISs prepared for previous lease sales (MMS, 2003, 2007b; BOEM, 2012c). The 

probability of a small spill would be minimized by Murphy’s preventative measures during 

routine operations, including fuel transfer. In the unlikely event of a spill, implementation of 

Murphy’s OSRP will reduce the potential impacts. Given the open ocean location of the lease 

area, the extent and duration of air quality impacts from a small spill would not be significant.

A small fuel spill would affect air quality near the spill site by introducing VOCs through 

evaporation. The ADIOS2 model (see Section A.9.2) indicates that over 90% of a small diesel 

spill would be evaporated or dispersed within 24 hours. The area of the sea surface with diesel 

fuel on it would range from 1.2 to 12 ac (0.5 to 5 ha) depending on sea state and weather 

conditions.

A small fuel spill would not affect coastal air quality because the spill would not be expected to 

make landfall or reach coastal waters prior to breaking up (see Section A.9.2).

Impacts of a Large Oil Spill (WCD)

Potential impacts of a large oil spill on air quality are expected to be consistent with those 

analyzed and discussed in previous lease sale EISs (MMS, 2003, 2007b; BOEM, 2012c).

A large oil spill (WCD) could potentially affect air quality by introducing VOCs through 

evaporation from the slick. The extent and persistence of impacts would depend on the 

meteorological and oceanographic conditions at the time and the effectiveness of spill response 

measures. Real-time wind and current data from the project area would be available at the 

time of a spill and would be used to assess the fate and effects of VOCs released. Additional air 

quality impacts could occur if response measures included in situ burning of the floating oil. 

Burning would generate a plume of black smoke and result in emissions of NOx, SOx, CO, and 

PM, as well as GHGs. However, in situ burning would occur only after authorization from the 

USEPA.
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Because of the lease area location (75 miles [121 km] from the nearest shoreline), most air 

quality impacts would occur in offshore waters. Depending on the spill trajectory and the 

effectiveness of spill response measures, coastal air quality could also be affected. Based on the 

OSRA (BOEM, 2012c) modeling predictions (Table 3), Plaquemines and St. Bernard Parishes, 

Louisiana; Jackson, Harrison, and Hancock Counties, Mississippi; Baldwin and Mobile Counties, 

Alabama; and Escambia County, Florida, are the coastal areas most likely to be affected.

C.1.2 Water Quality

There are no site-specific water quality data for the lease area. Because of the lease location in 

deep, offshore waters, water quality is expected to be good, with low levels of contaminants. 

As noted in a recent lease sale EIS (BOEM, 2012c), deepwater areas in the northern 

Gulf of Mexico are relatively homogeneous with respect to temperature, salinity, and oxygen. 

Kennicutt (2000) noted that the deepwater region has little evidence of contaminants in the 

dissolved or particulate phases of the water column. However, there are localized occurrences 

of natural seepage of oil, gas, and brines in near-surface sediments and up through the water 

column.

The lease area is located approximately 33 miles (53 km) from the Macondo spill site. Based on 

the general circulation pattern seen in the Gulf of Mexico and satellite imagery, the surface slick 

from that discharge extended over the lease area during the spill, and the existing water quality 

in the lease area could have been temporarily affected.

IPFs potentially affecting water quality are effluent discharges and two types of accidents: 

a small fuel spill and a large oil spill (WCD).

Impacts of Effluent Discharges

In general, turbid water can be expected to extend between a few hundred meters and several 

kilometers down current from the discharge point for water-based drilling muds and cuttings. 

SBMs will be collected on the rig and either reused by the vendor, or transported to 

Port Fourchon for recycling and/or disposal in an approved facility. Cuttings wetted with SBMs 

will be discharged to the seafloor in accordance with the NPDES permit. All NPDES permit 

limitations and requirements will be met. There will be no persistent impacts on water quality 

in the lease area (National Research Council, 1983; Neff, 1987; Neff et al., 2000).

Treated sanitary and domestic wastes, including those from support vessels, may have a slight 

transient effect on water quality in the immediate vicinity of these discharges. All NPDES permit 

limitations and requirements and USCG regulations (as applicable) will be met, therefore, little 

or no impact on water quality is anticipated.

Deck drainage includes all effluents resulting from rain, deck washings, and runoff from curbs, 

gutters, and drains, including drip pans in work areas. Rainwater that falls on uncontaminated 

areas of the drilling rig will flow overboard without treatment. However, rainwater that falls on 

the drilling rig deck and other areas such as chemical storage areas and places where equipment 

is exposed will be collected and oil and water separated to meet NPDES permit requirements. 

Based on adherence to permit limits and applicable regulations, little or no impact on water 

quality is anticipated.
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Other discharges in accordance with the NPDES permit, such as desalination unit brine and 

uncontaminated cooling water, fire water, and ballast water are expected to be diluted rapidly,

resulting in little or no impact on water quality.

Impacts of a Small Fuel Spill

Potential impacts of a small spill on water quality are expected to be consistent with those 

analyzed and discussed in recent EISs (MMS, 2007b; BOEM, 2012c). The probability of a small 

spill would be minimized by Murphy’s preventative measures during routine operations,

including fuel transfer. In the unlikely event of a spill, implementation of Murphy’s OSRP will 

potentially help mitigate and reduce the impacts. Given the open ocean location of the lease 

area, the extent and duration of water quality impacts from a small spill would not be 

significant.

A small fuel spill in offshore waters would produce a slick on the water surface and increase the 

concentrations of petroleum hydrocarbons and their degradation products. The extent and 

persistence of impacts would depend on the meteorological and oceanographic conditions at 

the time and the effectiveness of spill response measures. However, it is estimated that over 

90% of a small diesel spill would be evaporated or dispersed within 24 hours (see Section A.9.2). 

The area of the sea surface with diesel fuel on it would range from 1.2 to 12 ac (0.5 to 5 ha) 

depending on sea state and weather conditions.

The water-soluble fractions of diesel are dominated by two- and three-ringed PAHs, which are 

moderately volatile (National Research Council, 2003). The constituents of these oils are light to 

intermediate in molecular weight and can be readily degraded by aerobic microbial oxidation. 

Because the density of diesel is less than the density of seawater, diesel will not sink and pool on 

the seafloor. Diesel dispersed in the water column can adhere to suspended sediments, but this 

generally occurs only in coastal areas with high suspended solid loads (National Research 

Council, 2003) and would not be expected to occur to any appreciable degree in offshore waters 

of the Gulf of Mexico. Diesel oil is readily and completely degraded by naturally occurring 

microbes (NOAA, 2006).

A small fuel spill would not affect coastal water quality because the spill would not be expected 

to make landfall or reach coastal waters due to both response efforts that would be undertaken 

as well as natural attenuation (see Section A.9.2).

Impacts of a Large Oil Spill (WCD)

Potential impacts of a large oil spill on water quality are expected to be consistent with those 

analyzed and discussed in previous lease sale EISs (MMS, 2003, 2007b; BOEM, 2012b,c). A large 

spill would affect water quality by producing a slick on the water surface and increasing the 

concentrations of petroleum hydrocarbons and their degradation products. The extent and 

persistence of impacts would depend on the meteorological and oceanographic conditions at 

the time and the effectiveness of spill response measures. Most of the oil would be expected to 

form a slick at the surface, although new information from the Macondo spill indicates that 

plumes of submerged oil droplets can be produced when subsea dispersants are applied at the 

wellhead (Camilli et al., 2010; Hazen et al., 2010; Joint Analysis Group, 2010a,b,c). However, 

dispersants would be applied only after approval from the USEPA. Small droplets in the water 

may adhere to suspended sediments and be removed from the water column (Operational 

Scientific Advisory Team [OSAT], 2010).
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Because of the lease area location (75 miles [121 km] from the nearest shoreline), it is expected 

that most water quality impacts would occur in offshore waters. Depending on the spill 

trajectory and the effectiveness of spill response measures, coastal water quality could be 

affected. Based on the OSRA (BOEM, 2012c) modeling predictions (Table 3), Plaquemines and 

St. Bernard Parishes, Louisiana; Jackson, Harrison, and Hancock Counties, Mississippi; Baldwin 

and Mobile Counties, Alabama; and Escambia County, Florida, are the coastal areas most likely 

to be affected.

C.2 Seafloor Habitats and Biota

Water depths at the proposed well surface locations range from approximately 6,567 to 6,580 ft 

(2,002 to 2,006 m). The seafloor around the proposed wellsites is relatively smooth and stable. 

The immediate regions around the proposed well locations show no evidence of seafloor 

instability within 2,000 ft (610 m) of the wellsites. No areas of possible hard bottom or 

microseepages were seen within 2,000 ft (610 m) of any of the wellsites (GEMS, 2013).

The site clearance survey did not identify any features that could support high-density 

deepwater benthic communities within 2,000 ft (610 m) of the wellsites. No areas of gaseous 

sediments or possible hydrocarbon seepage were defined in the study area, and the presence of 

chemosynthetic communities is considered negligible (GEMS, 2013).

The BOEM uses a biologically based grid system to ensure broad and systematic analysis of the 

deepwater Gulf of Mexico, including remotely operated vehicle (ROV) coverage. The BOEM 

website indicates that ROV survey coverage for Grid 18, where the lease area is located, is 

adequate to characterize the area (BOEM, 2013b).

C.2.1 Soft Bottom Benthic Communities

There are no site-specific benthic community data from the lease area. However, data from the 

Northern Gulf of Mexico Continental Slope Habitats and Benthic Ecology Study (Wei, 2006; 

Rowe and Kennicutt, 2009) can be used to describe typical benthic communities in the area.

Table 4 summarizes data collected at stations in water depths similar to the proposed drilling 

area. Sediments at these stations were predominantly clay (51% to 57%) and silt (35% to 45%).

Table 4. Benthic community data from stations near the lease area and in greater water depths 

and more distant stations in more similar depths sampled during the Northern Gulf of 

Mexico Continental Slope Habitats and Benthic Ecology Study (Adapted from: 

Wei, 2006; Rowe and Kennicutt, 2009).

Station

Location 

Relative to 

Lease Area

Water Depth 

(m)

Abundance

Meiofauna

(individuals/m2)

Macroinfauna

(individuals/m2)

Megafauna

(individuals/ha)

S36 13 mi NE 1,826 799,963 4,481 359

S37 20 mi S 2,387 291,179 2,192 1,451

S38 50 mi SE 2,627 157,164 1,445 1,577

Meiofaunal and megafaunal abundances from Rowe and Kennicutt (2009); macroinfaunal abundance from 

Wei (2006).
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Faunal densities in the De Soto Canyon were high and were accompanied by high diversity. This 

variation from other sample sites may be due to the movement of riverine discharge from the 

Mississippi River into deeper water by cyclones (Rowe and Kennicutt, 2009).

Densities of meiofauna (animals passing through a 0.3-mm sieve but retained on a 0.062-mm 

sieve) in water depths representative of the lease area typically range from approximately 

165,000 to 800,000 individuals/m2 (Rowe and Kennicutt, 2009). Nematodes, nauplii, and 

harpacticoid copepods were the three dominant meiofaunal groups, accounting for about 

90% of total abundance.

The benthic macroinfauna is characterized by small mean individual sizes and low densities, 

both of which reflect the meager primary production in Gulf of Mexico surface waters 

(Wei, 2006). Densities decrease exponentially with water depth. Based on an equation 

presented by Wei (2006), macroinfaunal densities in the water depths of the lease area are 

expected to be about 1,600 individuals/m2

.

Polychaetes are typically the most abundant macroinfaunal group on the northern 

Gulf of Mexico continental slope, followed by amphipods, tanaids, bivalves, and isopods. Wei 

(2006) recognized four depth-dependent faunal zones (1 through 4), two of which are divided 

horizontally. Zone 2E, where the lease area is located, consists of stations in water depths 

ranging from 2,051 to 5,998 ft (625 to 1,828 m); the most abundant species in this zone were

the polychaetes Aricidea suecica, Litocorsa attenata, Paralacydonia paradoxa, and 

Tharyx marioni, followed by the bivalve Heterodonta sp. D.

Megafaunal densities from nearby stations ranged from 359 to 1,577 individuals/ha. Common 

megafauna included motile groups such as decapods, ophiuroids, holothurians, and demersal 

fishes as well as sessile groups such as sponges and anemones.

Bacteria also are an important component in terms of biomass and cycling of organic carbon 

(Cruz-Kaegi, 1998). Bacterial biomass at the depth range of the lease area typically is about 

1 to 2 g C/m2 in the top 15 cm of sediments (Rowe and Kennicutt, 2009).

IPFs potentially affecting benthic communities are physical disturbance to the seafloor, effluent 

discharges (drilling muds and cuttings), and a large oil spill (WCD) resulting from a well blowout 

at the seafloor. Because a DP semisubmersible will be used, there will be no seafloor 

disturbances from the use of anchors. A small fuel spill would not affect benthic communities 

because the diesel fuel would float and dissipate on the sea surface.

Impacts of Physical Disturbance to the Seafloor

In water depths such as are encountered in the lease area, DP drillships disturb the seafloor only 

around the wellbore (SHL) where the bottom template and BOP are located. Depending upon 

the specific well configuration, this area is generally about 0.62 ac (0.25 ha).

The areal extent of these impacts from the DP rig will be small compared to the lease area itself, 

and these type soft bottom communities are ubiquitous along the northern Gulf of Mexico 

continental slope (Gallaway, 1988; Gallaway et al., 2003; Rowe and Kennicutt, 2009). Impacts 

from the physical disturbance of the seafloor during this project will have no significant impact 

on soft bottom benthic communities in the region.
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Impacts of Effluent Discharges

Drilling muds and cuttings are the only effluents that are likely to affect benthic communities. 

During initial well interval(s) before the marine riser is set, cuttings and seawater-based "spud 

mud" will be released at the seafloor. Excess cement slurry will also be released at the seafloor 

during casing installation for the riserless portion of the drilling operations. Cement slurry 

components typically include cement mix and some of the same chemicals used in water-based 

drilling muds (Boehm et al., 2001). The main impacts will be burial and smothering of benthic 

organisms within several meters to tens of meters around the wellbore. Soft bottom sediments 

disturbed by cuttings, drilling muds, and cement slurry will eventually be recolonized through 

larval settlement and migration from adjacent areas. Because some deep-sea biota grow and 

reproduce slowly, recovery may require several years.

Discharges of washed SBM cuttings from the rig may affect benthic communities, primarily 

within several hundred meters of the wellsite. The fate and effects of SBM cuttings have been 

reviewed by Neff et al. (2000), and monitoring studies have been conducted in the 

Gulf of Mexico by Continental Shelf Associates, Inc. (2004, 2006). In general, washed cuttings 

with adhering SBMs tend to clump together and form thick cuttings piles close to the drillsite. 

Areas of SBM cuttings deposition may develop elevated organic carbon concentrations and 

anoxic conditions (Continental Shelf Associates, Inc., 2006). Where SBM cuttings accumulate in 

concentrations of approximately 1,000 mg/kg or higher, benthic infaunal communities may be 

adversely affected due to both the toxicity of the base fluid and organic enrichment (with 

resulting anoxia) (Neff et al., 2000). Infaunal numbers may increase and diversity may decrease 

as opportunistic species that tolerate low oxygen and high H2S predominate (Continental Shelf 

Associates, Inc., 2006). As the base synthetic fluid is decomposed by microbes, the area will 

gradually return to pre-drilling conditions. Disturbed sediments will be recolonized through 

larval settlement and migration from adjacent areas.

The areal extent of impacts from drilling discharges will be small. Assuming a typical effect 

radius of 1,640 ft (500 m), the affected area around the wellsite would represent about 3% of 

the seafloor within a lease block. 

Soft bottom communities are ubiquitous along the northern Gulf of Mexico continental slope 

(Gallaway, 1988; Gallaway et al., 2003; Rowe and Kennicutt, 2009). Impacts from drilling 

discharges during this project will have no significant impact on soft bottom benthic 

communities in the region.

Impacts of a Large Oil Spill (WCD)

The most likely effects of a subsea blowout on benthic communities would be within a few 

hundred meters of the wellsite. The MMS (2007b) estimated that a severe subsurface blowout 

could resuspend and disperse sediments within a 300-m (984-ft) radius. While coarse sediments 

(sands) would probably settle at a rapid rate within 1,312 ft (400 m) from the blowout site, fine 

sediments (silts and clays) could be resuspended for more than 30 days and dispersed over a 

much wider area. Based on previous studies, surface sediments at the project area are assumed 

to largely be silt and clay (Rowe and Kennicutt, 2009).
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Recent lease sale EIS (BOEM, 2012b) indicated that oil spills would be unlikely to affect benthic 

communities beyond the immediate vicinity of the wellhead (i.e., due to physical impacts of a 

blowout) because the oil would rise quickly to the sea surface directly over the spill location. 

However, during the Macondo spill, subsurface plumes were reported at a water depth of about 

3,600 ft (1,100 m), extending at least 22 miles (35 km) from the wellsite and persisting for more 

than a month (Camilli et al., 2010). The subsurface plumes apparently resulted from the use of 

dispersants at the wellhead (Joint Analysis Group, 2010c). While the behavior and impacts of 

subsurface plumes are not well known, a subsurface plume could contact the seafloor and affect 

benthic communities beyond the 300-m (984-ft) radius estimated by MMS (2007a), depending 

on its extent, trajectory, and persistence. This contact could result in smothering and/or toxicity 

to benthic organisms. The affected area would be recolonized by benthic organisms over a 

period of months to years (National Research Council, 2003).

C.2.2 High-Density Deepwater Benthic Communities

As defined by NTL 2009-G40, high-density deepwater benthic communities are features or areas 

that could support high-density chemosynthetic communities, or features or areas that could 

support high-density deepwater corals and other associated high-density hard-bottom 

communities. Chemosynthetic communities were discovered in the central Gulf of Mexico in 

1984 and have been studied extensively (MacDonald, 2002). Deepwater coral communities are 

also known from numerous locations in the Gulf of Mexico (Brooke and Schroeder, 2007; 

CSA International, Inc., 2007). These communities occur almost exclusively on authigenic 

carbonates created by chemosynthetic communities.

The nearest known chemosynthetic community site is approximately 29 miles (47 km)

north-norththwest of the lease area in Viosca Knoll Block 826. The nearest identified deepwater 

coral communities are also in Viosca Knoll Block 826.

The geohazards assessment of the lease area did not identify any features that could support 

high-density deepwater benthic communities within 2,000 ft (610 m) of the proposed drilling 

mud/cuttings discharge locations (GEMS, 2013).

IPFs potentially affecting high-density deepwater benthic communities include physical 

disturbance of the seafloor, effluent discharges (drilling muds and cuttings), and a large oil spill 

(WCD) from a well blowout at the seafloor. A small fuel spill would not affect benthic 

communities because the diesel fuel would float and dissipate on the sea surface.

Impacts of Physical Disturbance to the Seafloor

In water depths such as are encountered in the lease area, DP drillships disturb the seafloor only 

around the wellbore (SHL) where the bottom template and BOP are located. Depending upon 

the specific well configuration, this area is generally about 0.62 ac (0.25 ha).

The areal extent of these impacts from the DP rig will be small, and NTL 2009-G40 requires that 

high-density deepwater benthic communities and features or areas that could support 

high-density chemosynthetic communities, or deepwater corals communities be avoided. Based 

on the GEMS (2013) report, there will be no impacts on chemosynthetic or deepwater coral 

communities from this project.
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Impacts of Effluent Discharges

The site clearance survey (GEMS, 2013) did not identify any features that could support 

high-density deepwater benthic communities within 2,000 ft (610 m) of the proposed drilling 

locations, and the presence of chemosynthetic communities in the lease area is considered 

remote. Monitoring programs on the Gulf of Mexico continental slope have shown that benthic 

impacts from drilling discharges typically are concentrated within about 1,640 ft (500 m) of the 

wellsite, although detectable deposits may extend beyond this distance (Continental Shelf 

Associates, Inc., 2004, 2006; Neff et al., 2005). Because of the water depth of the lease area, 

drilling discharges would be expected to result in thinner, more diffuse accumulations on the 

seafloor than those documented in the literature. Although small amounts of cuttings particles 

may reach areas inhabited by high-density deepwater benthic communities, the discharges are 

not expected to result in significant impacts to these communities.

Impacts of a Large Oil Spill (WCD)

Previous analyses (MMS, 2007a) concluded that oil spills would be unlikely to affect benthic 

communities beyond the immediate vicinity of the wellhead (i.e., due to physical impacts of a 

blowout) because the oil would rise quickly to the sea surface directly over the spill location. 

However, during the Macondo spill, subsurface plumes were reported at a water depth of about 

3,600 ft (1,100 m), extending at least 22 miles (35 km) from the wellsite and persisting for more 

than a month (Camilli et al., 2010). The subsurface plumes apparently resulted from the use of 

dispersants at the wellhead (Joint Analysis Group, 2010c). While the behavior and impacts of 

subsurface plumes are not well known, a subsurface plume could have the potential to contact 

high-density deepwater benthic communities beyond the 300-m (984-ft) radius estimated by 

MMS (2007a), depending on its extent, trajectory, and persistence. Oil plumes that contact 

sensitive benthic communities before degrading could potentially impact the resource

(BOEM, 2012b). Potential impacts on sensitive resources would be an integral part of the 

decision and approval process for the use of dispersants, and such approval would be obtained 

from the USEPA prior to the use of dispersants.

The biological effects and expected fate of the oil remaining in the Gulf of Mexico from the 

blowout are still unknown due to the depth and the magnitude of this event. Hazen et al. (2010) 

reported changes in plume hydrocarbon composition with distance from the source. Incubation 

experiments with environmental isolates demonstrated faster than expected hydrocarbon 

biodegradation rates at 5°C. Based on these results, Hazen et al. (2010) suggested the potential 

exists for intrinsic bioremediation of the oil plume in the deep water column without substantial 

oxygen drawdown.

Potential impacts of oil on high-density deepwater benthic communities are discussed in 

MMS (2007b). Although chemosynthetic communities live among hydrocarbon seeps, natural 

seepage is very constant and occurs at low rates compared to the potential rates of oil release 

from a blowout. In addition, seep organisms also require unrestricted access to oxygenated 

water at the same time as exposure to hydrocarbon energy sources (MacDonald, 2002). Oil 

droplets or oiled sediment particles could come into contact with chemosynthetic organisms or 

deepwater corals. As discussed by MMS (2007b), impacts could include loss of habitat, 

biodiversity, and live coral coverage; destruction of hard substrate; change in sediment 

characteristics; and reduction or loss of one or more commercial and recreational fishery 
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habitats. Sublethal effects could be long-lasting and affect the resilience of coral colonies to 

natural disturbances (e.g., elevated water temperature and diseases).

The potential for a spill to affect deepwater corals is indicated by preliminary findings from a 

recent (October 2010) survey of deepwater coral habitats near the Macondo spill site 

(BOEMRE, 2010). Government and academic researchers were working at a site 4,600 ft 

(1,400 m) deep and approximately 7 miles (11 km) southwest of the Macondo wellhead when 

they observed dead and dying corals with sloughing tissue and discoloration. Much of the soft 

coral observed in an area measuring about 50 ft x 130 ft (15 m x 40 m) was covered by what 

appeared to be a brown flocculent substance (floc). Out of 40 large corals, 90% were heavily 

affected and showed dead and dying parts and discoloration. Another site 1,312 ft (400 m) 

farther away had a colony of stony corals similarly affected and partially covered with a similar 

brown substance. Based on hopanoid petroleum biomarkers from the floc, researchers 

concluded that it contained oil from the Macondo spill. The injured and dead corals were in an 

area where a subsea plume of oil had been documented during the spill in June, 2010; corals 

elsewhere in the Gulf of Mexico outside the area affected by the plume did not appear to be 

experiencing higher mortality. The research team concluded that the observed coral injuries 

likely resulted from exposure to the subsurface oil plume (White et al., 2012).

C.2.3 Designated Topographic Features

The block is not within or near a designated topographic feature or a no-activity zone as 

identified in NTL 2009-G39. The nearest designated topographic feature is Sackett Bank in West 

Delta Area, South Addition Block 147, 102 miles (164 km) west of the lease area.

There are no IPFs associated with either routine operations or accidents that could cause 

impacts to designated topographic features due to the distance from the lease area. A small 

fuel spill would float and dissipate on the surface and would not reach these seafloor features.

In the event of an oil spill from a well blowout, a surface slick would not contact these seafloor 

features. If a subsurface plume were to occur, impacts on these features would be unlikely due 

to the distance and the difference in water depth. Near-bottom currents in the region are 

predicted to flow along the isobaths (Nowlin et al., 2001) and typically would not carry a plume 

up onto the continental shelf edge.

C.2.4 Pinnacle Trend Area Live Bottoms

The lease area is not covered by the Live Bottom (Pinnacle Trend) Stipulation. As defined by 

NTL 2009-G39, the nearest pinnacle trend area is in Viosca Knoll Block 697, 35 miles (57 km)

north of the lease area.

There are no IPFs associated with either routine operations or accidents that could cause 

impacts to pinnacle trend area live bottoms due to the distance from the lease area. A small 

fuel spill would float on the surface and would not reach these seafloor features.

In the event of an oil spill from a well blowout, a surface slick would not contact these seafloor 

features. If a subsurface plume were to occur, impacts on these features would be unlikely due 

to the distance and the difference in water depth. Near-bottom currents in the region are 

predicted to flow along the isobaths (Nowlin et al., 2001) and typically would not carry a plume 

up onto the continental shelf edge.
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C.2.5 Eastern Gulf Live Bottoms

The lease area is not covered by the Live Bottom (Low-Relief) Stipulation, which pertains to 

seagrass communities and low-relief hard-bottom reef within the Gulf of Mexico Eastern 

Planning Area blocks in water depths of 100 m (328 ft) or less and portions of Pensacola and 

Destin Dome area blocks in the Central Planning Area. The nearest block covered by the live 

bottom stipulation, as defined by NTL 2009-G39, is Destin Dome Block 573, approximately 

43 miles (68 km) north of the lease area.

There are no IPFs associated with either routine operations or accidents that could cause 

impacts to eastern Gulf live bottom areas due to the distance from the lease area. A small fuel 

spill would float and dissipate on the surface and would not reach these seafloor features.

In the event of an oil spill from a well blowout, a surface slick would not contact these seafloor 

features. If a subsurface plume were to occur, impacts on these features would be unlikely due 

to the distance and the difference in water depth. Near-bottom currents in the region are 

predicted to flow along the isobaths (Nowlin et al., 2001) and typically would not carry a plume 

up onto the continental shelf.

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

This section discusses species listed as endangered or threatened under the Endangered Species 

Act (ESA). In addition, it includes all marine mammal species in the region, which are protected 

under the Marine Mammal Protection Act (MMPA), and all marine species listed on the State of

Florida’s Endangered and Threatened Species List maintained by the Florida Fish and Wildlife 

Conservation Commission (FWC).

Endangered or threatened species that may occur in the project area and/or along the northern 

Gulf Coast are listed in Table 5. The table also indicates the location of critical habitat (if

designated in the Gulf of Mexico). Critical habitat is defined as (1) specific areas within the 

geographical area occupied by the species at the time of listing, if they contain physical or 

biological features essential to conservation, and those features may require special 

management considerations or protection; and (2) specific areas outside the geographical area 

occupied by the species if the agency determines that the area itself is essential for 

conservation. The National Marine Fisheries Service (NMFS) has jurisdiction for ESA-listed 

cetaceans, sea turtles, and fishes in the Gulf of Mexico. The USFWS has jurisdiction for 

ESA-listed birds and the West Indian manatee.

Table 5. Federally listed endangered and threatened species potentially occurring in the lease 

area and along the northern Gulf Coast.

Species Scientific Name Status

Potential Presence Critical Habitat Designated 

in Gulf of Mexico Lease 

Area Coastal

Marine Mammals

Sperm whale Physeter macrocephalus E X -- None

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

Blue whale Balaenoptera musculus E Xa -- None

Fin whale Balaenoptera physalus E Xa -- None

Humpback whale Megaptera novaeangliae E Xa -- None

North Atlantic right whale Eubalaena glacialis E Xa -- None

Sei whale Balaenoptera borealis E Xa -- None
Table 5. (Continued).

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Species Scientific Name Status

Potential Presence Critical Habitat Designated 

in Gulf of Mexico Lease 

Area Coastal

Sea Turtles

Loggerhead turtle Caretta caretta T X X None

Green turtle Chelonia mydas T, Eb X X None

Leatherback turtle Dermochelys coriacea E X X None

Hawksbill turtle Eretmochelys imbricata E X X None

Kemp’s ridley turtle Lepidochelys kempii E X X None

Birds

Piping Plover Charadrius melodus T -- X

Coastal Texas, Louisiana, 

Mississippi, Alabama, and 

Florida (Panhandle)

Whooping Crane Grus americana E -- X

Coastal Texas 

(Aransas National Wildlife 

Refuge)

Fishes

Gulf sturgeon Acipenser oxyrinchus desotoi T -- X

Coastal Louisiana, 

Mississippi, Alabama, and 

Florida (Panhandle)

Smalltooth sawfish Pristis pectinata E -- X Southwest Florida and the 

Florida Keys

Invertebrates

Elkhorn coral Acropora palmata E -- X Flower Garden Banks

Terrestrial Mammals

Beach mice (Alabama, 

Choctawhatchee, 

Perdido Key, 

St. Andrew)

Peromyscus polionotus E -- X Alabama and Florida 

(Panhandle) beaches

Abbreviations: E = endangered; T = threatened. a The blue, fin, humpback, North Atlantic right, and sei whales are rare or extralimital in the Gulf of Mexico and are unlikely

to be present in the lease area. b The green sea turtle is threatened, except for the Florida breeding population, which is listed as endangered.

As mandated by the ESA, BOEMRE consulted NMFS and the USFWS on possible and potential 

impacts from the proposed leasing in the Gulf of Mexico on endangered/threatened species and 

their designated critical habitat (MMS, 2007a,b). A Biological Assessment was prepared for each 

consultation. The formal ESA consultation with NMFS was concluded with receipt of the 

Biological Opinion on 3 July 2007 (NMFS, 2007). The Biological Opinion concludes that the 

proposed lease sales and associated activities in the Five-Year Leasing Plan for Western and 

Central Planning Areas 2007-2012 are not likely to jeopardize the continued existence of 

threatened and endangered species under NMFS jurisdiction or destroy or adversely modify 

designated critical habitat. The informal ESA consultation with USFWS was concluded with a 

letter dated 14 September 2007. The USFWS concurred with MMS’s determination that 

proposed actions of the current Five-Year Leasing Plan were not likely to adversely affect 

threatened/endangered species or designated critical habitat under USFWS jurisdiction. 

Following the Macondo spill, BOEMRE requested to reinitiate an ESA consultation with both 

NMFS and USFWS on 30 July 2010. The NMFS responded with a letter to BOEMRE on 

24 September 2010, and the USFWS responded with a letter to BOEMRE on 27 September 2010. 

At present, the NMFS and USFWS have placed the consultation process on hold because they 

feel the environmental baseline information needs to be updated for the post-Macondo spill 

environment based on the results of the Natural Resource Damage Assessment (NRDA) process. 

The NRDA data have yet to be released, and the existing consultation remains in effect (BOEM, 
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2012c). The existing consultation recognizes that BOEM-required mitigations and other 

reasonable and prudent measures should reduce the likelihood of impacts from all 

BOEM-authorized activities in the Gulf of Mexico.

Coastal endangered or threatened species that may occur along the northern Gulf Coast include 

the West Indian manatee, Piping Plover, Whooping Crane, Gulf sturgeon, and four subspecies of 

beach mouse. Critical habitat has been designated for all of these species as indicated in Table 5

and discussed in individual sections.

Two other coastal species (Bald Eagle and Brown Pelican) are discussed in the MMS (2007b) 

lease sale EIS are no longer listed as endangered or threatened. These are discussed in 

Section C.4.2, Shorebirds and Coastal Nesting Birds.

The sperm whale and five species of sea turtles are the only endangered or threatened species 

likely to occur at or near the lease area. No critical habitat has been designated for these 

species in the Gulf of Mexico.

Five endangered mysticete whales (blue whale, fin whale, humpback whale, North Atlantic right 

whale, and sei whale) also have been reported from the Gulf of Mexico but are considered rare 

or extralimital there (Würsig et al., 2000). No critical habitat has been designated for these 

species in the Gulf of Mexico.

C.3.1 Sperm Whale (Endangered)

The only endangered marine mammal likely to be present at or near the project area is the 

sperm whale (Physeter macrocephalus). Resident populations of sperm whales occur within the 

Gulf of Mexico; a species description is presented in the Final Programmatic EIS (BOEM, 2012a).

Gulf of Mexico sperm whales are classified as an endangered species and a "strategic stock"

(defined as a stock that may have unsustainable human-caused impacts) by NOAA Fisheries 

(Waring et al., 2012). No critical habitat for the sperm whale has been designated in the 

Gulf of Mexico.

The distribution of sperm whales in the Gulf of Mexico is correlated with mesoscale physical 

features such as eddies associated with the Loop Current (Jochens et al., 2008). Sperm whale 

populations in the north-central Gulf of Mexico are present there throughout the year

(Davis et al., 2000). Results of a multi-year tracking study show female sperm whales typically 

concentrated along the upper continental slope between the 656- and 3,280-ft (200- and 

1,000-m) depth contours (Jochens et al., 2008). Male sperm whales were more variable in their 

movements and were documented in water depths greater than 9,843 ft (3,000 m). Generally, 

groups of sperm whales sighted in the Gulf of Mexico during the MMS-funded Sperm Whale 

Seismic Study (SWSS) consisted of mixed-sex groups comprising adult females and immatures, 

and groups of bachelor males. Typical group size for mixed groups was 10 individuals 

(Jochens et al., 2008). SWSS results show that sperm whales transit through the vicinity of the 

lease area. Movements of satellite-tracked individuals suggest that this area of the Gulf 

continental slope is within the home range of the Gulf of Mexico population (within the 

95% utilization distribution) (Jochens et al., 2008).

IPFs potentially affecting sperm whales include drilling rig presence, noise, and lights; support 

vessel and helicopter traffic; and two types of accidents – a small fuel spill and a large oil spill 

(WCD). Effluent discharges are likely to have negligible impacts on sperm whales due to rapid 
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dispersion, the small area of ocean affected, the intermittent nature of the discharges, and the 

mobility of these marine mammals. Compliance with NTL 2012-BSEE-G01 will minimize the 

potential for marine debris-related impacts on sperm whales.

Current threats to sperm whale populations worldwide are discussed in a final recovery plan for 

the sperm whale recently published by NOAA (NMFS, 2010a). Threats are defined as "any factor 

that could represent an impediment to recovery," and include fisheries interactions, 

anthropogenic noise, vessel interactions, contaminants and pollutants, disease, injury from 

marine debris, research, predation and natural mortality, direct harvest, competition for 

resources, loss of prey base due to climate change and ecosystem change, and cable laying.

In the Gulf of Mexico, the impacts from many of these threats are identified as either low or 

unknown (BOEM, 2012a,c).

Impacts of Drilling Rig Presence, Noise, and Lights

Noise from routine drilling activities has the potential to disturb sperm whales. Sperm whales 

appear to have good low-frequency hearing, but the available data do not indicate a consistent 

response to anthropogenic noise (Jochens et al., 2008). Noise intensity associated with drilling 

is relatively weak, and the noise exposure of an individual animal would be transient. There are 

other OCS facilities and activities near the lease area, and the region as a whole has a large 

number of similar noise sources. Due to the limited scope and short duration of drilling 

activities, this project would represent a small temporary contribution to the overall noise 

regime.

NMFS analyzed the potential for impacts of drilling-related noise on sperm whales in its 

Biological Opinion for the Gulf of Mexico Oil and Gas Activities: Five-Year Leasing Plan for 

Western and Central Planning Areas 2007-2012 (NMFS, 2007). The analysis noted that 

semisubmersible drilling rigs emit low sound source levels and concluded that drilling is not 

expected to produce amplitudes sufficient to cause hearing or behavioral effects in sperm 

whales; therefore, these effects are insignificant (NMFS, 2007).

Drilling rig lighting and rig presence are not identified as IPFs for sperm whales in previous lease 

sale EISs (MMS, 2007b; BOEM, 2012b,c) or the NMFS (2007) Biological Opinion.

Impacts of Support Vessel and Helicopter Traffic

Support vessel traffic has the potential to disturb sperm whales, and there is also a risk of vessel 

strikes, which are identified as a threat in the recovery plan for this species (NMFS, 2010a). Data 

concerning the frequency of vessel strikes are presented in a previous lease sale EIS 

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

NTL 2012-JOINT-G01, which recommends protected species identification training and that 

vessel operators and crews maintain a vigilant watch for marine mammals and slow down or 

stop their vessel to avoid striking protected species, and requires operators to report sightings 

of any injured or dead protected species. When whales are sighted, vessel operators and crews 

are required to attempt to maintain a distance of 300 ft (91 m) or greater whenever possible. 

Vessel operators are required to reduce vessel speed to 10 knots or less, when safety permits,

when mother/calf pairs, pods, or large assemblages of cetaceans are observed near an 

underway vessel. Compliance with this NTL will minimize the likelihood of vessel strikes as well 

as reduce the chance for disturbing sperm whales.
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NMFS (2007) analyzed the potential for vessel strikes and harassment of sperm whales. With 

implementation of the mitigation measures in NTL 2012-JOINT-G01, NMFS concluded that the 

likelihood of collisions between vessels and sperm whales would be reduced to insignificant 

levels. NMFS concluded that the observed avoidance of passing vessels by sperm whales is an 

advantageous response to avoid a potential threat and is not expected to result in any 

significant effect on migration, breathing, nursing, breeding, feeding, or sheltering to individuals, 

or have any consequences at the population level. With implementation of the vessel strike 

avoidance measures requirement to maintain a distance of 300 ft (91 m) from sperm whales, 

the NMFS concluded that the potential for harassment of sperm whales would be reduced to 

discountable levels.

Helicopter traffic also has the potential to disturb sperm whales. Smultea et al. (2008) 

documented responses of sperm whales offshore Hawaii to fixed wing aircraft flying at an 

altitude of 800 ft (245 m). A reaction to the initial pass of the aircraft was observed during 

3 (12%) of 24 sightings. All three reactions consisted of a hasty dive and occurred at less than 

1,180 ft (360 m) lateral distance from the aircraft. Additional reactions were seen when aircraft 

circled certain whales to make further observations. Based on other studies of cetacean 

responses to sound, the authors concluded that the observed reactions to brief overflights by 

the aircraft were short-term and probably of no long-term biological significance.

While flying offshore in the Gulf of Mexico, helicopters maintain altitudes above 700 ft (213 m) 

during transit to and from the working area. In the event that a whale is seen during transit, the 

helicopter will not approach or circle the animals. Although responses are possible (Smultea 

et al., 2008), the NMFS (2007) and BOEM (2012d) concluded that this altitude would minimize 

the potential for disturbing sperm whales. Therefore, no significant impacts are expected.

Impacts of a Small Fuel Spill

Potential spill impacts on marine mammals including sperm whales are discussed in recent lease 

sale EISs (MMS, 2007b; BOEM, 2012b,c) and by NMFS (2007). Oil impacts on marine mammals 

are discussed by Geraci and St. Aubin (1990). For this EP, there are no unique site-specific issues 

with respect to spill impacts on these animals that were not analyzed in the previous 

documents.

The probability of a fuel spill will be minimized by Murphy’s preventative measures during 

routine operations including fuel transfer. In the unlikely event of a spill, implementation of 

Murphy’s OSRP will mitigate and lessen the potential for impacts on sperm whales. Given the 

open ocean location of the lease area, the duration of a small spill and opportunity for impacts 

to occur would be very brief.

A small fuel spill in offshore waters would produce a slick on the water surface and increase the 

concentrations of petroleum hydrocarbons and their degradation products. The extent and 

persistence of impacts would depend on the meteorological and oceanographic conditions at 

the time and the effectiveness of spill response measures. Section A.9.2 discusses the likely fate 

of a small fuel spill and indicates that over 90% would be evaporated or dispersed naturally 

within 24 hours. The area of the sea surface with diesel fuel on it would range from 1.2 to 12 ac 

(0.5 to 5 ha), depending on sea state and weather conditions.

Direct physical and physiological effects of exposure to diesel fuel could include skin irritation, 

inflammation, or necrosis; chemical burns of skin, eyes, and mucous membranes; inhalation of 
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toxic fumes; ingestion of oil directly or via contaminated prey; and stress from the activities and 

noise of response vessels and aircraft (Marine Mammal Commission [MMC], 2011). However,

due to the limited areal extent and short duration of water quality impacts from a small fuel 

spill, as well as the mobility of sperm whales, no significant impacts would be expected.

Impacts of a Large Oil Spill (WCD)

Potential spill impacts on marine mammals including sperm whales are discussed in recent EISs 

(MMS, 2007b; BOEM, 2012a,b,c) and by NMFS (2007). For this EP, there are no unique 

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

Impacts of oil spills on sperm whales can include direct impacts from oil exposure, as well as 

indirect impacts due to response activities and materials (e.g., vessel traffic, noise, and 

dispersants) (MMC, 2011). Direct physical and physiological effects can include skin irritation, 

inflammation, or necrosis; chemical burns of skin, eyes, and mucous membranes; inhalation of 

toxic fumes; ingestion of oil (and dispersants) directly or via contaminated prey; and stress from 

the activities and noise of response vessels and aircraft. Complications of the above may lead to 

dysfunction of immune and reproductive systems, physiological stress, declining physical 

condition, and death. Behavioral responses can include displacement of animals from prime 

habitat, disruption of social structure, changing prey availability and foraging distribution and/or 

patterns, changing reproductive behavior/productivity, and changing movement patterns or 

migration (MMC, 2011).

In the event of a large spill, the level of vessel and aircraft activity associated with spill response 

could disturb sperm whales and potentially result in vessel strikes, entanglement, or other injury 

or stress. Response vessels would operate in accordance with NTL 2012-JOINT-G01 to reduce 

the potential for striking or disturbing these animals.

C.3.2 West Indian Manatee (Endangered)

Most of the Gulf of Mexico manatee population is located in peninsular Florida (USFWS, 2001). 

Manatee sightings in Louisiana have increased as the species extends its presence farther west 

of Florida in the warmer months (Wilson, 2003). A species description is presented in a recent 

lease sale EIS (BOEM, 2012a) and in the recovery plan for this species (USFWS, 2001).

IPFs potentially affecting manatees include support vessel and helicopter traffic and a large oil 

spill (WCD). A small fuel spill in the lease area would be unlikely to affect manatees, as the lease 

area is approximately 75 miles (121 km) from the nearest shoreline (Louisiana). As explained in 

Section A.9.2, a small fuel spill would not be expected to make landfall or reach coastal waters 

prior to breaking up. Compliance with NTL 2012-BSEE-G01 will minimize the potential for 

marine debris-related impacts on manatees.

Impacts of Support Vessel and Helicopter Traffic

Support vessel traffic has the potential to disturb manatees, and there is also a risk of vessel 

strikes, which are identified as a threat in the recovery plan for this species (USFWS, 2001). 

To reduce the potential for vessel strikes, BSEE and BOEM issued NTL 2012-JOINT-G01, which 

recommends protected species identification training and that vessel operators and crews 

maintain a vigilant watch for marine mammals and slow down or stop their vessel to avoid 

striking protected species, and requires operators to report sightings of any injured or dead 
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protected species. Compliance with this NTL will minimize the likelihood of vessel strikes, and 

no significant impacts on manatees are expected.

Helicopter traffic also has the potential to disturb manatees. Rathbun (1988) reported that 

manatees were disturbed more by helicopters than by fixed-wing aircraft; however, the 

helicopter was flown at relatively low altitudes of 66 to 525 ft (20 to 160 m). Helicopters used in 

support operations maintain a minimum altitude of 700 ft (213 m) while in transit offshore, 

1,000 ft (305 m) over unpopulated areas or across coastlines, and 2,000 ft (610 m) over 

populated areas and sensitive habitats such as wildlife refuges and park properties. In addition, 

guidelines and regulations specify that helicopters maintain an altitude of 1,000 ft (305 m) 

within 300 ft (91 m) of marine mammals (BOEM, 2012a,b). This mitigation measure will 

minimize the potential for disturbing manatees, and no significant impacts are expected.

Impacts of a Large Oil Spill (WCD)

In the event that manatees were exposed to oil, effects could include direct impacts from oil 

exposure, as well as indirect impacts due to response activities and materials (e.g., vessel traffic, 

noise, and dispersants) (MMC, 2011). Direct physical and physiological effects can include skin 

irritation, inflammation, or necrosis; chemical burns of skin, eyes, and mucous membranes; 

inhalation of toxic fumes; ingestion of oil (and dispersants) directly or via contaminated prey 

(or contaminated vegetation, in the case of manatees); and stress from the activities and noise 

of response vessels and aircraft. Complications of the above may lead to dysfunction of immune 

and reproductive systems, physiological stress, declining physical condition, and death. 

Behavioral responses can include displacement of animals from prime habitat, disruption of 

social structure, changing prey availability and foraging distribution and/or patterns, changing 

reproductive behavior/productivity, and changing movement patterns or migration 

(MMC, 2011).

In the event that a large spill reached coastal waters where manatees were present, the level of 

vessel and aircraft activity associated with spill response could disturb manatees and potentially 

result in vessel strikes, entanglement, or other injury or stress. Response vessels would operate 

in accordance with NTL 2012-JOINT-G01 to reduce the potential for striking or disturbing these 

animals, and therefore no significant impacts are expected.

C.3.3 Endangered Mysticete Whales

Five endangered mysticete whales (blue whale, fin whale, humpback whale, North Atlantic right 

whale, and sei whale) also have been reported from the Gulf of Mexico but are considered rare 

or extralimital there (Würsig et al., 2000). No critical habitat has been designated for these 

species in the Gulf of Mexico.

Because of the rare occurrence of these whales in the Gulf of Mexico and the limited scope and 

duration of the project, it is highly unlikely that any endangered mysticete whales would come 

into contact with any project activities, either routine operations or accidents. NMFS did not 

include any of these mysticete whales as affected species in its Biological Opinion (NMFS, 2007). 

Potential impacts are analyzed in previous lease sale EISs (MMS, 2007b; BOEM, 2012a,b,c), and 

those analyses are incorporated by reference. If any of these whales were present in the area, 

potential impacts would be the same as those discussed below in Section C.3.4.
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C.3.4 Non-Endangered Marine Mammals (Protected)

Excluding the seven endangered species that have been cited previously, there are 22 additional 

species of marine mammals that may be found in the Gulf of Mexico, including 2 species of 

mysticete whales, 2 species of sperm whales, 4 species of beaked whales, and 14 species of

delphinids. All marine mammals are protected species under the MMPA. The most common 

non-endangered cetaceans in the deepwater environment are odontocetes such as the 

pantropical spotted dolphin, spinner dolphin, and Clymene dolphin. A brief summary is

presented below, and additional information on these groups is presented in a recent lease sale 

EIS (MMS, 2007b).

Mysticete whales. Two species of nonendangered mysticete whales are known from the 

Gulf of Mexico. The Bryde’s whale (Balaenoptera edeni) has been sighted most frequently along 

the 328-ft (100-m) isobath (Davis and Fargion, 1996; Davis et al., 2000). Most sightings have 

been made in the De Soto Canyon region and off western Florida, although there have been 

some in the west-central portion of the northeastern Gulf. The minke whale 

(Balaenoptera acutorostrata) is considered rare in the Gulf of Mexico, with the only confirmed 

records coming from strandings (Würsig et al., 2000). Based on the available data, it is possible 

that Bryde’s whales could occur in the lease area.

Dwarf and pygmy sperm whales. At sea, it is difficult to differentiate dwarf sperm whales 

(Kogia sima) from pygmy sperm whales (Kogia breviceps), and sightings are often grouped 

together as Kogia spp. Both species have a worldwide distribution in temperate to tropical 

waters. In the Gulf of Mexico, both species occur primarily along the continental shelf edge and 

in deeper waters off the continental shelf (Mullin et al., 1991). Either species could occur in the 

lease area.

Beaked whales. Four species of beaked whales are known from the Gulf of Mexico. They are 

Blainville’s beaked whale (Mesoplodon densirostris), Cuvier’s beaked whale (Ziphius cavirostris), 

Sowerby’s beaked whale (Mesoplodon bidens), and Gervais’ beaked whale 

(Mesoplodon europaeus). Stranding records in the Gulf of Mexico suggest that Gervais’ beaked 

whale is the most common and Sowerby’s is extralimital. Due to the difficulties of at-sea 

identification, beaked whales in the Gulf of Mexico are identified either as Cuvier’s beaked 

whales or are grouped into an undifferentiated complex (Mesoplodon spp. and Ziphius spp.). In 

the northern Gulf of Mexico, they are broadly distributed in water depths greater than 3,281 ft 

(1,000 m) over lower slope and abyssal landscapes (Davis et al., 2000). Any of these species 

could occur in the lease area.

Delphinids. Fourteen species of delphinids are known from the Gulf of Mexico, including 

Atlantic spotted dolphin (Stenella frontalis), bottlenose dolphin (Tursiops truncatus), 

Clymene dolphin (Stenella clymene), false killer whale (Pseudorca crassidens), Fraser’s dolphin

(Lagenodelphis hosei), killer whale (Orcinus orca), melon-headed whale (Peponocephala electra), 

pantropical spotted dolphin (Stenella attenuata), pygmy killer whale (Feresa attenuata), 

short-finned pilot whale (Globicephala macrorhynchus), Risso’s dolphin (Grampus griseus), 

rough-toothed dolphin (Steno bredanensis), spinner dolphin (Stenella longirostris), and 

striped dolphin (Stenella coeruleoalba). Any of these species could occur in the lease area. The 

most common nonendangered cetaceans in the deepwater environment are the pantropical 

spotted dolphin, spinner dolphin, and Clymene dolphin.
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Bottlenose dolphins. Bottlenose dolphin populations in the northern Gulf of Mexico are 

separated by the NMFS into 37 geographically distinct population units, or stocks, for 

management purposes (Waring et al., 2012). NMFS (2013) has proposed to classify the 

Gulf of Mexico Northern Coastal Stock, Western Coastal Stock, and all 32 of the Bay, Sound, and 

Estuarine Stocks as strategic stocks, based primarily on the occurrence of an "unusual mortality 

event" of unprecedented size and duration (which began in February 2010 and is ongoing) that 

has affected these stock areas. Carmichael et al. (2012) hypothesized that the unusual number 

of bottlenose dolphin strandings in the northern Gulf of Mexico during this time may have been 

associated with environmental perturbations including sustained cold weather and the 

Macondo spill in 2010 as well as large volumes of cold freshwater discharge in the early months 

of 2011.

IPFs potentially affecting non-endangered marine mammals include drilling rig presence, noise, 

and lights; support vessel and helicopter traffic; and two types of accidents – a small fuel spill 

and a large oil spill (WCD). Effluent discharges are likely to have negligible impacts on marine 

mammals due to rapid dispersion, the small area of ocean affected, the intermittent nature of 

the discharges, and the mobility of marine mammals. Compliance with NTL 2012-BSEE-G01 will 

minimize the potential for marine debris-related impacts on marine mammals.

Impacts of Drilling Rig Presence, Noise, and Lights

Noise from routine drilling activities has the potential to disturb marine mammals. Most 

odontocetes (toothed whales and dolphins) use higher frequency sounds than those produced 

by OCS drilling activities (Richardson et al., 1995). Noise intensity associated with drilling is 

relatively weak, and the noise exposure of an individual animal would be transient. There are 

other OCS facilities and activities near the lease area, and the region as a whole has a large 

number of similar sources. Due to the limited scope and short duration of drilling activities, this 

project would represent a small temporary contribution to the overall noise regime, and any 

short-term impacts are not expected to be biologically significant to marine mammal 

populations.

Drilling rig lighting and rig presence are not identified as IPFs for marine mammals in previous 

lease sale EISs (MMS, 2007b; BOEM, 2012a,b,c).

Impacts of Support Vessel and Helicopter Traffic

Support vessel traffic has the potential to disturb marine mammals, and there is also a risk of 

vessel strikes. Data concerning the frequency of vessel strikes are presented in a previous lease 

sale EIS (MMS, 2007b). To reduce the potential for vessel strikes, BSEE and BOEM issued

NTL 2012-JOINT-G01, which recommends protected species identification training and that 

vessel operators and crews maintain a vigilant watch for marine mammals and slow down or 

stop their vessel to avoid striking protected species, and requires operators to report sightings 

of any injured or dead protected species. Vessel operators and crews are required to attempt to 

maintain a distance of 300 ft (91 m) or greater when whales are sighted and 150 ft (45 m) when 

small cetaceans are sighted. When cetaceans are sighted while a vessel is underway, vessels 

must attempt to remain parallel to the animal’s course and avoid excessive speed or abrupt 

changes in direction until the cetacean has left the area. Vessel operators are required to 

reduce vessel speed to 10 knots or less when mother/calf pairs, pods, or large assemblages of 

cetaceans are observed near an underway vessel, when safety permits. Compliance with 
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NTL 2012-JOINT-G01 will minimize the likelihood of vessel strikes as well as reduce the chance 

for disturbing marine mammals, and therefore no significant impacts are expected.

Aircraft traffic also has the potential to disturb marine mammals (Würsig et al., 1998). However, 

while flying offshore, helicopters maintain altitudes above 700 ft (213 m) during transit to and 

from the working area. In addition, guidelines and regulations specify that helicopters maintain 

an altitude of 1,000 ft (305 m) within 300 ft (91 m) of marine mammals (BOEM, 2012a,b). 

Maintaining this altitude will minimize the potential for disturbing marine mammals, and no 

significant impacts are expected (BOEM, 2012a,b).

Impacts of a Small Fuel Spill

Potential spill impacts on marine mammals are discussed in recent EISs (BOEM, 2012b,c), and oil 

impacts on marine mammals in general are discussed by Geraci and St. Aubin (1990). For this 

EP, there are no unique site-specific issues with respect to spill impacts on these animals.

The probability of a fuel spill will be minimized by Murphy’s preventative measures during fuel 

transfer. In the unlikely event of a spill, implementation of Murphy’s OSRP is expected to lessen 

the potential for impacts on marine mammals. Given the open ocean location of the lease area, 

the limited duration of a small spill and response efforts, it is expected that any impacts would 

be brief and minimal.

A small fuel spill in offshore waters would produce a slick on the water surface and increase the 

concentrations of petroleum hydrocarbons and their degradation products. The extent and 

persistence of impacts would depend on the meteorological and oceanographic conditions at 

the time and the effectiveness of spill response measures. Section A.9.2 discusses the likely fate 

of a small fuel spill and indicates that over 90% would be evaporated or dispersed naturally 

within 24 hours. The area of the sea surface with diesel fuel on it would range from 1.2 to 12 ac 

(0.5 to 5 ha), depending on sea state and weather conditions.

Direct physical and physiological effects of exposure to diesel fuel could include skin irritation, 

inflammation, or necrosis; chemical burns of skin, eyes, and mucous membranes; inhalation of 

toxic fumes; ingestion of oil directly or via contaminated prey; and stress from the activities and 

noise of response vessels and aircraft (MMC, 2011). However, due to the limited areal extent 

and short duration of water quality impacts from a small fuel spill, as well as the mobility of 

marine mammals, no significant impacts would be expected.

Impacts of a Large Oil Spill (WCD)

Potential spill impacts on marine mammals are discussed in MMS (2000, 2007b) and BOEM 

(2012a,b). For this EP, there are no unique site-specific issues. Impacts of oil spills on marine 

mammals can include direct impacts from oil exposure, as well as indirect impacts due to 

response activities and materials (e.g., vessel traffic, noise, and dispersants) (MMC, 2011). 

Direct physical and physiological effects can include skin irritation, inflammation, or necrosis; 

chemical burns of skin, eyes, and mucous membranes; inhalation of toxic fumes; ingestion of oil 

(and dispersants) directly or via contaminated prey (or contaminated vegetation, in the case of 

manatees); and stress from the activities and noise of response vessels and aircraft. 

Complications of the above may lead to dysfunction of immune and reproductive systems, 

physiological stress, declining physical condition, and death. Behavioral responses can include 

displacement of animals from prime habitat, disruption of social structure, changing prey 
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availability and foraging distribution and/or patterns, changing reproductive 

behavior/productivity, and changing movement patterns or migration (MMC, 2011).

In the event of a large spill, the level of vessel and aircraft activity associated with spill response 

could disturb marine mammals and potentially result in vessel strikes, entanglement, or other 

injury or stress. Response vessels would operate in accordance with NTL 2012-JOINT-G01 to 

reduce the potential for striking or disturbing these animals, and therefore no significant 

impacts are expected.

C.3.5 Sea Turtles (Endangered/Threatened)

Five species of endangered or threatened sea turtles may be found near the lease area. 

Leatherback (Dermochelys coriacea), Kemp's ridley (Lepidochelys kempii), and hawksbill 

(Eretmochelys imbricata) turtles are endangered. The loggerhead turtle (Caretta caretta) is 

currently a threatened species; however, in March 2010, NMFS and USFWS proposed to list the 

Northwest Atlantic Ocean population of loggerhead turtles as endangered (75 FR 12598). The 

green turtle (Chelonia mydas) is listed as threatened, except for the Florida and Pacific coast of 

Mexico breeding populations, which are listed as endangered. Species descriptions are 

presented in BOEM (2012a).

The extent and scope of the Macondo spill represents new information not assessed in the 

existing ESA Section 7 consultation under the current Five-Year Program. As a result of this new 

information, BOEMRE reinitiated ESA Section 7 consultation on the existing Gulf of Mexico lease 

sale EIS with NMFS and the USFWS on 30 July 2010. The NMFS responded with a letter to 

BOEMRE on 24 September 2010, and the USFWS responded with a letter to BOEMRE on 

27 September 2010. However, the NMFS and the USFWS have placed the consultation process 

on hold pending the results of the NRDA post-Macondo spill data review, which has yet to be 

released. The existing consultation currently remains in effect (BOEM, 2012c).

BOEM (2012b) reexamined the impacts analyses presented in MMS (2007b) for the five sea 

turtle species that inhabit the Gulf of Mexico based on additional information and in 

consideration of the Macondo spill. No new information was found that would alter the 

potential impacts on sea turtles described in previous EISs. In most foreseeable cases, exposure 

to hydrocarbons persisting in the sea following the dispersal of an oil slick will result in sublethal 

impacts (e.g., decreased health, reproductive fitness, and longevity; and increased vulnerability 

to disease) to sea turtles.

Leatherbacks and loggerheads are the most likely species to be present near the lease area as 

adults. Green, hawksbill, and Kemp’s ridley turtles are typically inner shelf and nearshore 

species, unlikely to occur near the lease area as adults. Hatchlings or juveniles of any of the sea 

turtle species may be present in deepwater areas, including the lease area, where they may be 

associated with Sargassum and other flotsam.

Sea turtle nesting in the northern Gulf of Mexico can be summarized by species as follows:

• Loggerhead turtles – Loggerheads nest in significant numbers along the Florida Panhandle 

and, to a lesser extent, from Texas through Alabama (MMS, 2007b). The nearest significant 

nesting area of loggerhead turtles is found in Louisiana, on beaches within the Breton NWR;

• Green and leatherback turtles – Green and leatherback turtles infrequently nest on Florida 

Panhandle beaches (Florida Fish and Wildlife Conservation Commission, 2012);
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• Kemp’s ridley turtles – The main Kemp’s ridley nesting site is Rancho Nuevo beach, 

Tamaulipas, Mexico (NMFS et al., 2011). Kemp’s ridley turtles typically do not nest 

anywhere near the project area, although there have been occasional reports of Kemp’s 

ridleys nesting in Alabama (Share the Beach, 2010); and

• Hawksbill turtles – Hawksbills typically do not nest anywhere near the project area.

IPFs potentially affecting sea turtles include drilling rig presence, noise, and lights; support 

vessel and helicopter traffic; and two types of accidents – a small fuel spill and a large oil spill 

(WCD). Effluent discharges are likely to have negligible impacts on sea turtles due to rapid 

dispersion, the small area of ocean affected, and the intermittent nature of the discharges.

Compliance with NTL 2012-BSEE-G01 will minimize the potential for marine debris-related 

impacts on sea turtles.

Impacts of Drilling Rig Presence, Noise, and Lights

Offshore drilling activities produce a broad array of sounds at frequencies and intensities that 

may be detected by sea turtles (Geraci and St. Aubin, 1987). Potential impacts may include 

behavioral disruption and temporary or permanent displacement from the area near the sound 

source. Certain sea turtles, especially loggerheads, may be attracted to offshore structures 

(Lohoefener et al., 1990) and, thus, may be more susceptible to impacts from sounds produced 

during routine operations. Helicopters and service vessels may also affect sea turtles due to 

machinery noise and/or visual disturbances. The most likely impacts would be short-term 

behavioral changes such as diving and evasive swimming, disruption of activities, or departure 

from the area. Due to the limited scope and short duration of drilling activities, these 

short-term impacts are not expected to be biologically significant to sea turtle populations.

Artificial lighting can disrupt the nocturnal orientation of sea turtle hatchlings (Witherington, 

1997; Tuxbury and Salmon, 2005). However, hatchlings may rely less on light cues when they 

are offshore than when they are emerging on the beach (Salmon and Wyneken, 1990). The 

NMFS (2007) concluded that the effects of lighting from offshore structures on sea turtles are 

insignificant.

Impacts of Support Vessel and Helicopter Traffic

Support vessel traffic has the potential to disturb sea turtles, and there is also a risk of vessel 

strikes. Data show that vessel traffic is one cause of sea turtle mortality in the Gulf of Mexico 

(Lutcavage et al., 1997). While adult sea turtles are visible at the surface during the day and in 

clear weather, they can be difficult to spot from a moving vessel when resting below the water 

surface, during nighttime, or during periods of inclement weather. To reduce the potential for 

vessel strikes, BSEE and BOEM issued NTL 2012-JOINT-G01, which recommends protected 

species identification training and that vessel operators and crews maintain a vigilant watch for 

sea turtles and slow down or stop their vessel to avoid striking protected species, and requires 

operators to report sightings of any injured or dead protected species. When sea turtles are 

sighted, vessel operators and crews are required to attempt to maintain a distance of 150 ft 

(45 m) or greater whenever possible. Compliance with this NTL will minimize the likelihood of 

vessel strikes as well as reduce the chance for disturbing sea turtles (NMFS, 2007).

Helicopter traffic also has the potential to disturb sea turtles. However, while flying offshore, 

helicopters maintain altitudes above 700 ft (213 m) during transit to and from the working area. 

This altitude will minimize the potential for disturbing sea turtles, and no significant impacts are 

expected.
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Impacts of a Small Fuel Spill

Potential spill impacts on sea turtles are discussed in previous EISs (BOEM, 2012b,c) and the 

NMFS Biological Opinion (NMFS, 2007). For this EP, there are no unique site-specific issues with 

respect to spill impacts on these animals.

The probability of a fuel spill will be minimized by Murphy’s preventative measures during fuel 

transfer. In the unlikely event of a spill, implementation of Murphy’s OSRP is expected to

minimize potential impacts on sea turtles. Given the open ocean location of the lease area, the 

duration of a small spill and opportunity for impacts to occur would be very brief.

A small fuel spill in offshore waters would produce a slick on the water surface and increase the 

concentrations of petroleum hydrocarbons and their degradation products. The extent and 

persistence of impacts would depend on the meteorological and oceanographic conditions at 

the time and the effectiveness of spill response measures. Section A.9.2 discusses the likely fate 

of a small fuel spill and indicates that over 90% would be evaporated or dispersed naturally 

within 24 hours. The area of the sea surface with diesel fuel on it would range from 1.2 to 12 ac 

(0.5 to 5 ha), depending on sea state and weather conditions.

Direct physical and physiological effects of exposure to diesel fuel could include skin irritation, 

inflammation, or necrosis; chemical burns of skin, eyes, and mucous membranes; inhalation of 

toxic fumes; ingestion of oil directly or via contaminated prey; and stress from the activities and 

noise of response vessels and aircraft. However, due to the limited areal extent and short 

duration of water quality impacts from a small fuel spill, no significant impacts would be 

expected.

A small fuel spill in the lease area would be unlikely to affect sea turtle nesting beaches, as the 

lease area is 75 miles (121 km) from the nearest shoreline (Louisiana). As explained in 

Section A.9.2, a small fuel spill would not be expected to make landfall or reach coastal waters 

prior to breaking up.

Impacts of a Large Oil Spill (WCD)

Impacts of oil spills on sea turtles can include direct impacts from oil exposure, as well as 

indirect impacts due to response activities and materials (e.g., vessel traffic, noise, and 

dispersants). Direct physical and physiological effects can include skin irritation, inflammation, 

or necrosis; chemical burns of skin, eyes, and mucous membranes; inhalation of toxic fumes and 

smoke (e.g., from in situ burning of oil); ingestion of oil (and dispersants) directly or via 

contaminated food; and stress from the activities and noise of response vessels and aircraft. 

Complications of the above may lead to dysfunction of immune and reproductive systems, 

physiological stress, declining physical condition, and death. Behavioral responses can include 

displacement of animals from prime habitat, disruption of social structure, changing food 

availability and foraging distribution and/or patterns, changing reproductive 

behavior/productivity, and changing movement patterns or migration. In the unlikely event of a 

spill, implementation of Murphy’s OSRP is expected to minimize the potential for these types of 

impacts on sea turtles. EP Attachments P and Q provide detail on spill response measures.

Studies of oil effects on loggerheads in a controlled setting (Lutcavage et al., 1995) suggest that 

sea turtles show no avoidance behavior when they encounter an oil slick, and any sea turtle in 

an affected area would be expected to be exposed. Sea turtles’ diving behaviors also put them 
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at risk. Sea turtles rapidly inhale a large volume of air before diving and continually resurface 

over time, which may result in repeated exposure to volatile vapors and oiling (NMFS, 2007).

Spilled oil reaching sea turtle nesting beaches could have effects on nesting sea turtles and egg 

development (NMFS, 2007). An oiled beach could affect nest site selection or result in no 

nesting at all (e.g., false crawls). Upon hatching and successfully reaching the water, hatchlings 

are subject to the same types of oil spill exposure hazards as adults. Hatchlings that contact oil 

residues while crossing a beach can exhibit a range of effects, from acute toxicity to impaired 

movement and normal bodily functions (NMFS, 2007).

In the event of a large spill, the level of vessel and aircraft activity associated with spill response 

could disturb sea turtles and potentially result in vessel strikes, entanglement, or other injury or 

stress. Response vessels would operate in accordance with NTL 2012-JOINT-G01 to reduce the 

potential for striking or disturbing these animals, and therefore no significant impacts are 

expected.

C.3.6 Piping Plover (Threatened)

The Piping Plover (Charadrius melodus) is a migratory shorebird that overwinters along the 

southeastern U.S. and Gulf of Mexico coasts. This threatened species is in decline as a result of 

hunting, habitat loss and modification, predation, and disease (USFWS, 2003). Critical 

overwintering habitat has been designated, including beaches in Texas, Louisiana, Mississippi, 

Alabama, and Florida (Figure 3). Piping Plovers inhabit coastal sandy beaches and mudflats, 

feeding by probing for invertebrates at or just below the surface. They use beaches adjacent to 

foraging areas for roosting and preening (USFWS, 2010a). A species description is presented in a 

recent lease sale EIS (BOEM, 2012a).

A large oil spill (WCD) is the only IPF potentially affecting Piping Plovers. There are no IPFs 

associated with routine project activities that could affect these birds. A small fuel spill in the 

lease area would be unlikely to affect Piping Plovers because a small fuel spill would not be 

expected to make landfall or reach coastal waters prior to breaking up (see explanation in 

Section A.9.2).

Impacts of a Large Oil Spill (WCD)

The lease area is 80 miles (128 km) from the nearest shorelines inhabited by Piping Plovers 

(Figure 3). The revised OSRA results (BOEM, 2012c) summarized in Section A.9.3 (Table 3) 

predict contact with shorelines of Mississippi, Louisiana, Alabama, and Florida within 30 days 

and shorelines of Texas within 120 days. Louisiana shorelines designated as critical habitat for 

the wintering Piping Plover could be contacted by a spill within 120 days including 

Plaquemines Parish which has the highest probability of contact (23% in winter, 25% in summer,

and 28% in fall). Plovers could physically oil themselves while foraging on oiled shores or 

secondarily contaminate themselves through ingestion of oiled intertidal sediments and prey 

(MMS, 2007b). Plovers congregate and feed along tidally exposed banks and shorelines, 

following the tide out and foraging at the water’s edge. It is possible that some deaths of 

Piping Plovers could occur, especially if spills occur during winter months when plovers are most 

common along the coastal Gulf or if spills contacted critical habitat. Impacts could also occur 

from vehicular traffic on beaches and other activities associated with spill cleanup. Murphy has 

extensive resources available to protect and rehabilitate wildlife in the event of a spill reaching 

the shoreline, as detailed in the OSRP.
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Figure 3. Location of selected environmental features in relation to the lease area.
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C.3.7 Whooping Crane (Endangered)

The Whooping Crane (Grus americana) is an omnivorous wading bird and an endangered 

species. There are three wild populations in North America (Whooping Crane Eastern 

Partnership, 2010). One population winters along the Texas coast at Aransas NWR and 

summers at Wood Buffalo National Park in Canada; this population represents the majority of 

the world’s population of free-ranging Whooping Cranes and reached a record population of 

270 at Aransas NWR in December 2008 (Whooping Crane Eastern Partnership, 2010). 

A nonmigrating population has been reintroduced in central Florida, and another reintroduced 

population summers in Wisconsin and migrates to the southeastern U.S. for the winter. 

Whooping Cranes breed, migrate, winter, and forage in a variety of habitats, including coastal 

marshes and estuaries, inland marshes, lakes, ponds, wet meadows and rivers, and agricultural 

fields (USFWS, 2007). About 22,240 ac (9,000 ha) of salt flats on Aransas NWR and adjacent 

islands comprise the principal wintering grounds of the Whooping Crane. Aransas NWR is 

designated as critical habitat for the species. A species description is presented in a recent lease 

sale EIS (BOEM, 2012a). A large oil spill (WCD) is the only IPF potentially affecting 

Whooping Cranes. A small fuel spill in the lease area would also be unlikely to affect 

Whooping Cranes, due to the distance from Aransas NWR. As explained in Section A.9.2, a 

small fuel spill would not be expected to make landfall or reach coastal waters prior to breaking 

up.

Impacts of a Large Oil Spill (WCD)

A large oil spill is unlikely to affect Whooping Cranes as the lease area is approximately 

524 miles (843 km) from its critical habitat designated in the Aransas NWR. The OSRA modeling 

predicts no contacts with shorelines of the Aransas NWR within 30 days and minimal probability 

of contact with nearby Texas coastlines within 120 days (BOEM, 2012c).

In the event of oil exposure, Whooping Cranes could physically oil themselves while foraging in 

oiled areas or secondarily contaminate themselves through ingestion of contaminated shellfish, 

frogs, and fishes. It is possible that some Whooping Crane deaths could occur. In the event of a 

spill, Murphy would work with the applicable State and Federal agencies to prevent impacts 

from a spill.

C.3.8 Gulf Sturgeon (Threatened)

The Gulf sturgeon (Acipenser oxyrinchus desotoi) is a threatened fish species that inhabits major 

rivers and inner shelf waters from the Mississippi River to the Suwannee River, Florida 

(Barkuloo, 1988; Wakeford, 2001). An anadromous fish that migrates from the sea upstream 

into coastal rivers to spawn in freshwater, it historically ranged from the Mississippi River to 

Charlotte Harbor, Florida (Wakeford, 2001). Today, this range has contracted to encompass 

major rivers and inner shelf waters from the Mississippi River to the Suwannee River, Florida. 

Populations have been depleted or even extirpated throughout this range by fishing, shoreline 

development, dam construction, water quality changes, and other factors (Barkuloo, 1988; 

Wakeford, 2001). These declines prompted the listing of the Gulf sturgeon as a threatened 

species in 1991. The best known populations occur in the Apalachicola and Suwannee Rivers in 

Florida (Carr, 1996; Sulak and Clugston, 1998), the Choctawhatchee River in Alabama (Fox et al., 

2000), and the Pearl River in Mississippi/Louisiana (Morrow et al., 1998). Critical habitat in the 

Gulf extends from Lake Borgne, Louisiana (St. Bernard Parish) to Suwannee Sound, Florida 

(Levy County) (NMFS, 2010b) (Figure 3). A species description is presented in a lease sale EIS 
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(BOEM, 2012a) and in the recovery plan for this species (USFWS and Gulf States Marine 

Fisheries Commission, 1995).

A large oil spill (WCD) is the only IPF potentially affecting Gulf sturgeon. There are no IPFs 

associated with routine project activities that could affect these fish. A small fuel spill in the 

lease area would be unlikely to affect Gulf sturgeon because a small fuel spill would not be 

expected to make landfall or reach coastal waters prior to breaking up (see explanation in 

Section A.9.2).

Impacts of a Large Oil Spill (WCD)

Potential spill impacts on Gulf sturgeon are discussed in previous lease sale EISs (MMS, 2007b; 

BOEM, 2012c) and by NMFS (2007). For this EP, there are no unique site-specific issues with 

respect to this species.

The lease area is approximately 102 miles (164 km) from the nearest Gulf sturgeon critical 

habitat. The revised OSRA modeling (BOEM, 2012c) predicts contact with coastal areas 

inhabited by Gulf sturgeon within 120 days. Plaquemines and St. Bernard Parishes, Louisiana;

Baldwin and Mobile Counties, Alabama; and Jackson County, Mississippi, coastal areas are the 

most likely to be affected. Florida and Texas coastlines can be contacted, but to a lesser extent.

In the event of oil reaching Gulf sturgeon habitat, the fish could be affected by direct ingestion, 

ingestion of oiled prey, or the absorption of dissolved petroleum products through the gills. 

Based on the life history of this species, subadult and adult Gulf sturgeon would be most 

vulnerable to an estuarine or marine oil spill, and would be vulnerable only from 

1 September through 30 April when this species is foraging in estuarine and shallow marine 

habitats (NMFS, 2007).

C.3.9 Smalltooth Sawfish (Endangered)

Smalltooth sawfish (Pristis pectinata) are found in the tropical and subtropical Atlantic Ocean. 

In the Western Atlantic they have historically ranged from New York to Brazil, including the 

Gulf of Mexico and Caribbean Sea. This sawfish primarily occurs in estuarine and coastal 

habitats such as bays, lagoons, and rivers. The smalltooth sawfish was listed as endangered 

under the ESA on 1 April 2003. Its critical habitat consists of two units: the Charlotte Harbor 

Estuary Unit, which comprises approximately 221,459 ac (89,621 ha) of coastal habitat; and the 

Ten Thousand Islands/Everglades Unit, which comprises approximately 619,013 ac (250,506 ha)

of coastal habitat. The two units are located along the southwestern coast of Florida between 

Charlotte Harbor and Florida Bay. A species description is presented in a lease sale EIS 

(BOEM, 2012a).

A large oil spill (WCD) is the only IPF potentially affecting smalltooth sawfish. There are no IPFs 

associated with routine project activities that could affect these fish. A small fuel spill in the 

lease area would be unlikely to affect smalltooth sawfish because a small fuel spill would not be 

expected to make landfall or reach coastal waters prior to breaking up (see Section A.9.2).

Impacts of a Large Oil Spill (WCD)

Potential spill impacts on smalltooth sawfish are similar to those discussed for other coastal and 

estuarine species in recent lease sale EISs (MMS, 2007b; BOEM, 2012b) and by the NMFS (2007) 
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in its Biological Opinion. For this EP, there are no unique site-specific issues with respect to 

smalltooth sawfish.

In the event of oil reaching smalltooth sawfish habitat, the fish could be affected by direct 

ingestion, ingestion of oiled prey, or the absorption of dissolved petroleum products through 

the gills.

C.3.10 Beach Mice (Endangered)

Four subspecies of endangered beach mouse (Peromyscus polionotus) occur on the barrier 

islands of Alabama and the Florida Panhandle. They are the Alabama, Choctawhatchee, 

Perdido Key, and St. Andrew beach mice. Critical habitat has been designated for all four 

subspecies; Figure 3 shows the critical habitat combined for all four subspecies. Species 

descriptions are provided in a recent lease sale EIS (BOEM, 2012a).

A large oil spill (WCD) is the only IPF potentially affecting beach mice. There are no IPFs 

associated with routine project activities that could affect these animals due to the distance 

from shore and the lack of any onshore support activities near their habitat. A small fuel spill in 

the lease area would not affect beach mice because a small fuel spill would not be expected to 

make landfall or reach coastal waters prior to breaking up (see Section A.9.2).

Impacts of a Large Oil Spill (WCD)

Potential spill impacts on beach mice are discussed in recent lease sale EISs (MMS, 2003, 2007b; 

BOEM, 2012b). For this EP, there are no unique site-specific issues with respect to these species

that were not analyzed in these documents.

The lease area is about 100 miles (160 km) south from the nearest beach mouse critical habitat. 

The revised OSRA modeling summarized in Section A.9.3 predicts that during different seasons, 

there is a 1% to 17% chance of oil contacting Alabama or Florida panhandle shorelines inhabited 

by Choctawatchee and St. Andrew beach mice within 120 days. It is expected that the entire 

spill volume would be removed due to natural weathering and response measures within that 

period.

In the event of oil contacting these beaches, beach mice could experience several types of direct 

and indirect impacts. Contact with spilled oil could cause skin and eye irritation and subsequent 

infection; matting of fur; irritation of sweat glands, ear tissues, and throat tissues; disruption of 

sight and hearing; asphyxiation from inhalation of fumes; and toxicity from ingestion of oil and 

contaminated food. Indirect impacts could include reduction of food supply, destruction of 

habitat, and fouling of nests. Impacts could also occur from vehicular traffic and other activities 

associated with spill cleanup. However, any such impacts are unlikely due to the distance from 

shore and response actions that would occur in the event of a spill.

C.3.11 Elkhorn Coral (Endangered)

Elkhorn coral (Acropora palmata) is found primarily in shallow waters with temperatures ranging

between 26°C and 30°C (79°F and 86°F) and significant water movement. Elkhorn coral was 

once one of the most abundant coral species in waters ranging from 3.3 to 16 ft (1 to 5 m) deep

in tropical and subtropical waters. In the northern Gulf of Mexico, elkhorn coral has been found 

within the coral cap region of the Flower Garden Banks National Marine Sanctuary

(Flower Garden Banks National Marine Sanctuary, 2011).
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There are no IPFs associated with routine project activities that could affect this species in the 

northern Gulf of Mexico. A small fuel spill would not affect elkhorn coral colonies because the 

oil would float and dissipate on the sea surface. A WCD would be unlikely to affect the coral cap 

region of the Flower Garden Banks because of the water depth of the area. Although 

subsurface plumes were reported following the Macondo spill, these plumes resulted from the 

use of subsea dispersants at the seafloor.

C.4 Coastal and Marine Birds

C.4.1 Marine Birds

Marine birds include seabirds and other species that may occur in the pelagic environment of 

the project area (Clapp et al., 1982a,b, 1983; Peake, 1996; Hess and Ribic, 2000). Seabirds spend 

much of their lives offshore over the open ocean, except during breeding season when they nest 

along the coast. In addition, other birds such as waterfowl, marsh birds, and shorebirds may 

occasionally be present over open ocean areas. No endangered or threatened bird species are 

likely to occur at the project area due to the distance from shore. For a discussion of shorebirds 

and coastal nesting birds, see Section C.4.2.

Seabirds of the northern Gulf of Mexico were surveyed from ships during the GulfCet II program. 

Hess and Ribic (2000) reported that terns, storm-petrels, shearwaters, and jaegers were the 

most frequently sighted seabirds in the deepwater area. From these surveys, four ecological 

categories of seabirds were documented in the deepwater areas of the Gulf: summer migrants 

(shearwaters, storm petrels, boobies); summer residents that breed in the Gulf (Sooty Tern, 

Least Tern, Sandwich Tern, Magnificent Frigatebird); winter residents (gannets, gulls, jaegers); 

and permanent resident species (Laughing Gulls, Royal Terns, Bridled Terns) (Hess and Ribic, 

2000).

Common seabird species include Wilson’s Storm-Petrel (Oceanites oceanicus), Magnificent 

Frigatebird (Fregata magnificens), Northern Gannet (Morus bassanus), Masked Booby 

(Sula dactylatra), Brown Booby (Sula leucogaster), Cory’s Shearwater (Calonectris diomedea), 

Greater Shearwater (Puffinus gravis), and Audubon’s Shearwater (Puffinus lherminieri). Seabirds 

are distributed Gulf-wide and are not specifically associated with the lease area.

Relationships with hydrographic features were found for several seabird species, possibly due to 

effects of hydrography on nutrient levels and productivity of surface waters where birds forage. 

The GulfCet II study did not estimate bird densities; however, Powers (1987) indicates that 

seabird densities over the open ocean typically are <10 birds/km2

.

Trans-Gulf migrant birds including shorebirds, wading birds, and terrestrial birds may also be 

present in the lease area. Migrant birds may use offshore structures and rigs for resting, 

feeding, or as temporary shelter from inclement weather (Russell, 2005). Some birds may be 

attracted to offshore structures because of the lights and the fish populations that aggregate 

around these structures.

IPFs potentially affecting marine and pelagic birds include drilling rig presence, noise, and lights; 

support vessel and helicopter traffic; and two types of accidents - a small fuel spill and a large oil 

spill (WCD). Effluent discharges are likely to have negligible impacts on the birds due to rapid 

dispersion, the small area of ocean affected, the intermittent nature of the discharges, and the 
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mobility of these animals. Compliance with NTL 2012-BSEE-G01 will minimize the potential for 

marine debris-related impacts on birds.

Impacts of Drilling Rig Presence, Noise, and Lights

Birds that frequent rigs may be exposed to contaminants including air pollutants and routine 

discharges, but significant impacts are unlikely due to rapid dispersion. Birds migrating over 

water have been known to strike offshore structures, resulting in death or injury (Wiese et al., 

2001; Russell, 2005). Mortality of migrant birds at tall towers and other land-based structures 

has been reviewed extensively, and the mechanisms involved in rig collisions appear to be 

similar. In some cases, migrants simply do not see a part of the rig until it is too late. In other 

cases, navigation may be disrupted by noise (Russell, 2005). On the other hand, offshore 

structures are suitable stopover habitats for most trans-Gulf migrant species, and most of the 

migrants that stop over on rigs probably benefit from their stay, particularly in spring 

(Russell, 2005). Due to the limited scope and short duration of drilling activities described in this 

EP, any impacts on populations of either seabirds or trans-Gulf migrant birds are not expected 

to be significant.

A study in the North Sea indicated that rig lighting causes circling behavior in various birds, 

especially on cloudy nights; apparently the birds’ geomagnetic compass is upset by the red part 

of the spectrum from the lights currently in use (Nederlandse Aardolie Maatschappij, 2007). 

The numbers varied greatly, from none at all to some tens of thousands of birds per night per 

rig, with an apparent effect radius of up to 3 miles (5 km). The OSPAR workshop (OSPAR 

Commission, 2012) noted that this circling increases the risk of collisions leading to traumas and 

deaths and may interrupt their migration. A study in the Gulf of Mexico also noted the 

phenomenon but did not recommend mitigation (Russell, 2005). Factors to consider in 

evaluating this impact in the Gulf of Mexico would include the lower incidence of cloudy and 

foggy days in the Gulf of Mexico versus the North Sea. In laboratory experiments, Poot et al. 

(2008) found the magnetic compass of migratory birds to be wavelength dependent. Migratory 

birds require light from the blue-green part of the spectrum for magnetic compass orientation, 

whereas red light (visible long-wavelength) disrupts their magnetic orientation. They designed a 

field study to test if and how changing light color influenced migrating birds under field 

conditions. During field studies they found that nocturnally migrating birds were disoriented 

and attracted by red and white light (containing visible long-wavelength radiation), whereas 

they were clearly less disoriented by blue and green light (containing less or no visible 

long-wavelength radiation) (Poot et al., 2008). Due to the limited scope and short duration of 

drilling activities proposed in this EP, lighting impacts, collisions, or other adverse effects are 

unlikely, and no significant impacts are expected.

Impacts of Support Vessel and Helicopter Traffic

Support vessels and helicopters are unlikely to significantly disturb pelagic birds in open, 

offshore waters. It is likely that individual birds would experience, at most, only short-term 

behavioral disruption, and the impact would not be significant.

Impacts of a Small Fuel Spill

Potential spill impacts on marine birds are discussed in previous EISs (MMS, 2007b; BOEM, 2012 

a,b). For this EP, there are no unique site-specific issues with respect to spill impacts on these 

animals.
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The probability of a fuel spill will be minimized by Murphy’s preventative measures during 

routine operations including fuel transfer. In the unlikely event of a spill, implementation of 

Murphy’s OSRP will reduce the potential for impacts on marine and pelagic birds. Given the 

open ocean location of the lease area, the duration of a small spill and opportunity for impacts 

to occur would be very brief.

A small fuel spill in offshore waters would produce a slick on the water surface and increase the 

concentrations of petroleum hydrocarbons and their degradation products. The extent and 

persistence of impacts would depend on the meteorological and oceanographic conditions at 

the time and the effectiveness of spill response measures. Section A.9.2 discusses the likely fate 

of a small fuel spill and indicates that over 90% would be evaporated or dispersed naturally 

within 24 hours. The area of the sea surface with diesel fuel on it would range from 1.2 to 12 ac 

(0.5 to 5 ha), depending on sea state and weather conditions.

Birds exposed to oil on the sea surface could experience direct physical and physiological effects

including skin irritation; chemical burns of skin, eyes, and mucous membranes; and inhalation of 

toxic fumes. Due to the limited areal extent and short duration of water quality impacts from a 

small fuel spill, secondary impacts due to ingestion of oil via contaminated prey or reductions in 

prey abundance are unlikely. Due to the low densities of birds in open ocean areas, the small 

area affected, and the brief duration of the surface slick, no significant impacts on pelagic birds 

would be expected.

Impacts of a Large Oil Spill (WCD)

Potential spill impacts on marine and pelagic birds are discussed in previous EISs (MMS, 2003, 

2007b; BOEM, 2012 a,b). For this EP, there are no unique site-specific issues with respect to 

spill impacts on these animals.

BOEM has reexamined the analyses for coastal and marine birds presented in MMS (2007b) and 

determined that no new information was found that would alter the potential impacts on

marine and pelagic birds (BOEM, 2012c).

Pelagic seabirds could be exposed to oil from a spill at the project area. Hess and Ribic (2000) 

reported that terns, storm-petrels, shearwaters, and jaegers were the most frequently sighted 

seabirds in the deepwater Gulf of Mexico (>200 m). Powers (1987) indicates that seabird 

densities over the open ocean typically are <10 birds/km2

. The number of pelagic birds that 

could be affected in open, offshore waters would depend on the extent and persistence of the 

oil slick.

The recent Macondo spill provides relevant information about the species of pelagic birds that 

may be affected in the event of a large oil spill. Birds that have been treated for oiling include 

several pelagic species such as the Northern Gannet, Magnificent Frigatebird, and 

Masked Booby (USFWS, 2011). The Northern Gannet is among the species with the largest 

numbers of birds affected by the spill.

C.4.2 Shorebirds and Coastal Nesting Birds

Threatened and endangered bird species (Piping Plover and Whooping Crane) have been 

discussed previously in Section C.3. Various species of nonendangered birds are also found 

along the northern Gulf Coast, including diving birds, shorebirds, marsh birds, wading birds, and 
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waterfowl. Gulf Coast marshes and beaches also provide important feeding grounds and 

nesting habitats. Species that breed on beaches, flats, dunes, bars, barrier islands, and similar 

habitats include the Sandwich Tern, Wilson’s Plover, Black Skimmer, Forster’s Tern, 

Gull-Billed Tern, Laughing Gull, Least Tern, and Royal Tern (USFWS, 2010b). Additional

information is presented in recent lease sale EISs (MMS, 2007b; BOEM, 2012b).

The Brown Pelican (Pelecanus occidentalis) was delisted from Federal endangered status in 2009 

(USFWS, 2010c). However, this species remains endangered on the Louisiana list of endangered 

species (State of Louisiana, Department of Wildlife and Fisheries, 2013), is listed as a species of 

greatest conservation need by the State of Mississippi (Mississippi Department of Wildlife, 

Fisheries and Parks, 2011), and is a species of special concern in Florida (Florida Fish and Wildlife 

Conservation Commission, 2012). Brown Pelicans inhabit coastal habitats and forage within 

both coastal waters and waters of the inner continental shelf. Aerial and shipboard surveys, 

including GulfCet and GulfCet II, indicate that Brown Pelicans do not occur in deep offshore 

waters (Fritts and Reynolds, 1981; Peake, 1996; Hess and Ribic, 2000). Nearly half the 

southeastern population of Brown Pelicans lives in the northern Gulf Coast, generally nesting on 

protected islands (USFWS, 2010b).

The Southern Bald Eagle (Haliaeetus leucocephalus) was delisted from its threatened status in 

the lower 48 states on 28 June 2007. The Bald Eagle is a terrestrial raptor widely distributed 

across the southern U.S., including coastal habitats along the Gulf of Mexico. The Gulf Coast is 

inhabited by both wintering migrant and resident Bald Eagles (Johnsgard, 1990; Ehrlich et al., 

1992).

IPFs potentially affecting shorebirds and coastal nesting birds include support vessel and 

helicopter traffic and a large oil spill (WCD). A small fuel spill in the lease area would be unlikely 

to affect shorebirds or coastal nesting birds, as the lease area is 75 miles (121 km) from the 

nearest shoreline. As explained in Section A.9.2, a small fuel spill would not be expected to 

make landfall or reach coastal waters prior to breaking up. Compliance with NTL 2012-BSEE-G01

will minimize the potential for marine debris-related impacts on shorebirds.

Impacts of Support Vessel and Helicopter Traffic

Support vessels and helicopters will transit coastal areas near Port Fourchon and Galliano, 

Louisiana, where shorebirds and coastal nesting birds may be found. These activities could 

periodically disturb individuals or groups of birds within sensitive coastal habitats (e.g., wetlands 

that may support feeding, resting, or breeding birds).

Vessel traffic may disturb some foraging and resting birds. Flushing distances vary between 

species and between individuals (Rodgers and Schwikert, 2002). The disturbances will be 

limited to flushing birds away from vessel pathways; known distances are from 65 to 160 ft 

(20 to 49 m) for personal watercraft and 75 to 190 ft (23 to 58 m) for an outboard-powered boat 

(Rodgers and Schwikert, 2002). Flushing distances may be similar or less for the support vessels 

to be used for Murphy’s project, and some species such as gulls are attracted to boats. Support 

vessels will not approach nesting or breeding areas on the shoreline, so disturbances to nesting 

birds, eggs, and chicks are not expected. Vessel operators will use designated navigation 

channels and comply with posted speed and wake restrictions while transiting sensitive inland 

waterways. Due to the limited scope and short duration of drilling activities, any short-term 

impacts are not expected to be biologically significant to coastal bird populations.
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Aircraft traffic can cause some disturbance to birds onshore and offshore. Responses are highly 

dependent on the type of aircraft, the bird species, the activities that animals were previously 

engaged in, and previous exposures to overflights (Efroymson et al., 2000). Helicopters seem to 

cause the most intense responses over other human disturbances for some species (Bélanger 

and Bédard, 1989). However, Federal Aviation Administration Advisory Circular No. 91-36D 

recommends that pilots maintain a minimum altitude of 2,000 ft (610 m) when flying over 

noise-sensitive areas such as wildlife refuges, parks, and areas with wilderness characteristics. 

This is greater than the distance (slant range) at which aircraft overflights have been reported to 

cause behavioral effects on most species of birds studied (Efroymson et al., 2000). With these 

guidelines in effect, it is likely that individual birds would experience, at most, only short-term 

behavioral disruption.

Impacts of Large Oil Spill (WCD)

Data from the Macondo spill provide additional information about the species of coastal birds 

that may be affected in the event of a catastrophic spill of a similar nature and duration. This 

information supplements the analysis presented in the lease sale EIS (MMS, 2007b). According 

to USFWS (2010d) and based on the latest reports, about 5,000 dead birds have been collected 

since the spill began, and about 1,900 of the dead animals were visibly oiled. In addition, over 

3,000 oiled birds have been collected alive and about 1,200 released (USFWS, 2011). According 

to USFWS (2011), bird species that have been treated for oiling include the following:

• Brown Pelican

• White Pelican

• Masked Booby

• Magnificent 

Frigatebird

• Laughing Gull

• Herring Gull

• Northern Gannet

• Black Crowned Night 

Heron

• Tri-colored Heron

• Green Heron

• Cattle Egret

• Snowy Egret

• Reddish Egret

• Least Bittern

• Common Tern

• Royal Tern

• Caspian Tern

• Sandwich Tern

• Forster’s Tern

• Black Tern

• Gull-billed Tern

• Least Tern

• Black Skimmer

• Black Oystercatcher

• White Ibis

• Roseate Spoonbill

• Willet

• Sanderling

• Dunlin

• Semipalmated 

Sandpiper

• Killdeer

• King Rail

• Clapper Rail

• Virginia Rail

According to the USFWS (2010d), species with the largest numbers of dead oiled birds were 

Laughing Gull, Northern Gannet, Brown Pelican, Royal Tern, Black Skimmer, Least Tern, 

unidentified Gull, and unidentified Tern. There are no reports of Bald Eagle oiling.

While the Macondo spill had direct and indirect impacts to coastal and marine birds, it is 

premature to conclude impacts over a long period (BOEM, 2012c). Modeling of Macondo spill 

related bird impacts is underway by NRDA, but results have not yet been released. 

Antonio et al. (2011) modeled bird-mortality from the Macondo spill showing cumulative 

carcass numbers and mortality rate increasing exponentially from the start of the Macondo spill 

until the mortality rate began to decline after the 97th day of the spill. Note that the collected 

animals would be a small subset of the total number of impacted birds and therefore, the 

collected animals would represent an underestimated measure of the overall impact of the 

Macondo event (BOEM, 2012c).
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Coastal birds can be exposed to oil as they float on the water surface, dive during foraging, or 

wade in oiled coastal waters. Oiled birds can lose the ability to fly, dive for food, or float on the 

water, which could lead to drowning (USFWS, 2010e). Oil interferes with the water repellency 

of feathers and can cause hypothermia in the right conditions. As birds groom themselves, they 

can ingest and inhale the oil on their bodies. Scavengers such as Bald Eagles and gulls can be 

exposed to oil by feeding on carcasses of contaminated fish and wildlife. While ingestion can kill 

animals immediately, more often it results in lung, liver, and kidney damage, which can lead to 

death. Bird eggs may be damaged if an oiled adult sits on the nest.

As noted above, the Brown Pelican was recently removed from the Federal endangered species 

list. Over 300 dead Brown Pelicans were collected in the Gulf following the Macondo spill, 

(USFWS, 2010d). These data indicate that Brown Pelicans may be particularly at risk of oiling in 

the event of a catastrophic spill reaching coastal waters. Issues for Brown Pelicans include direct 

contact with oil, disturbance by cleanup activities, and long-term habitat contamination.

C.5 Fisheries Resources

C.5.1 Pelagic Communities and Ichthyoplankton

Biggs and Ressler (2000) reviewed the biology of pelagic communities in the deepwater 

environment of the northern Gulf of Mexico. The biological oceanography of the region is 

dominated by the influence of the Loop Current, whose surface waters are among the most 

oligotrophic in the world’s oceans. Superimposed on this low-productivity condition are 

productive "hot spots" associated with entrainment of nutrient-rich Mississippi River water and 

mesoscale oceanographic features. Anticyclonic and cyclonic hydrographic features play an 

important role in determining biogeographic patterns and controlling primary productivity in the 

northern Gulf of Mexico (Biggs and Ressler, 2000).

Most fishes inhabiting shelf or oceanic waters of the Gulf of Mexico have planktonic eggs and 

larvae (Ditty, 1986; Ditty et al., 1988; Richards et al., 1989, 1993). Pelagic eggs and larvae 

become part of the planktonic community for various lengths of time (10 to 100 days, 

depending on the species) (MMS, 2007b).

IPFs potentially affecting pelagic communities and ichthyoplankton include drilling rig presence, 

noise, and lights; effluent discharges; water intakes; and two types of accidents -a small fuel spill 

and a large oil spill (WCD).

Impacts of Drilling Rig Presence, Noise, and Lights

The drilling rig, as a floating structure in the deepwater environment, will act as a fish-attracting 

device (FAD). In oceanic waters, the FAD effect would be most pronounced for epipelagic fishes 

such as tunas, dolphin, billfishes, and jacks, which are commonly attracted to fixed and drifting 

surface structures (Holland et al., 1990; Higashi, 1994; Relini et al., 1994; MMS, 2000, 2007b). 

This FAD effect could possibly enhance the feeding of epipelagic predators by attracting and 

concentrating smaller fish species. Because the drilling rig is a single, temporary structure, 

impacts on fish populations, whether beneficial or adverse, are considered minor.

Impacts of Effluent Discharges

Treated sanitary and domestic wastes may have a slight effect on the pelagic environment in the 

immediate vicinity of these discharges. These wastes may have elevated levels of nutrients, 
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organic matter, and chlorine, but should be diluted rapidly to undetectable levels within tens to 

hundreds of meters from the source. Minimal impacts on water quality, plankton, and nekton 

are anticipated.

Deck drainage may have a slight effect on the pelagic environment in the immediate vicinity of 

these discharges. Deck drainage from contaminated areas will be passed through an 

oil-and-water separator prior to release, and discharges will be monitored for visible sheen. The 

discharges may have slightly elevated levels of hydrocarbons but should be diluted rapidly to 

undetectable levels within tens to hundreds of meters from the source. Minimal impacts on 

water quality, plankton, and nekton are anticipated.

Other discharges in accordance with the NPDES permit, such as desalination unit brine and 

uncontaminated cooling water, fire water, and ballast water, are expected to be diluted rapidly 

and have little or no impact on water column biota.

Impacts of Water Intakes

Seawater will be drawn from the ocean for once-through, noncontact cooling of machinery 

on the drilling rig. Rigs considered for use for activities described in this EP are not "new"

facilities as defined by the NPDES permit and therefore are not subject to the cooling water 

intake regulations for Phase III facilities under Section 316(b) of the Clean Water Act.

The intake of seawater for cooling water will entrain plankton. The low intake velocity should 

allow most strong-swimming juvenile fishes and smaller adults to escape entrainment or 

impingement. However, drifting plankton would not be able to escape entrainment with the 

exception of a few fast-swimming larvae of certain taxonomic groups. Those organisms 

entrained may be stressed or killed, primarily through changes in water temperature during the 

route from cooling intake structure to discharge structure and mechanical damage (turbulence 

in pumps and condensers). Due to the limited scope and short duration of drilling activities, any 

short-term impacts of entrainment are not expected to be biologically significant to plankton or 

ichthyoplankton populations.

Impacts of a Small Fuel Spill

Potential spill impacts on fisheries resources are discussed in recent EISs (MMS, 2007b; 

BOEM, 2012a,b). For this EP, there are no unique site-specific issues with respect to spill 

impacts.

The probability of a fuel spill will be minimized by Murphy’s preventative measures during 

routine operations including fuel transfer. In the unlikely event of a spill, implementation of 

Murphy’s OSRP will mitigate the potential for impacts on pelagic communities, including 

ichthyoplankton. Given the open ocean location of the lease area, the duration of a small spill 

and opportunity for impacts to occur would be very brief.

A small fuel spill in offshore waters would produce a slick on the water surface and increase the 

concentrations of petroleum hydrocarbons and their degradation products. The extent and 

persistence of impacts would depend on the meteorological and oceanographic conditions at 

the time and the effectiveness of spill response measures. Section A.9.2 discusses the likely fate 

of a small fuel spill and indicates that over 90% would be evaporated or dispersed naturally 
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within 24 hours. The area of the sea surface with diesel fuel on it would range from 1.2 to 12 ac 

(0.5 to 5 ha), depending on sea state and weather conditions.

A small fuel spill could have localized impacts on phytoplankton, zooplankton, and nekton. 

Due to the limited areal extent and short duration of water quality impacts, a small fuel spill 

would be unlikely to produce detectable impacts on pelagic communities.

Impacts of a Large Oil Spill (WCD)

A large oil spill could affect water column biota including phytoplankton, zooplankton, 

ichthyoplankton, and nekton. A large spill that persisted for weeks or months would be more 

likely to affect these communities. While adult and juvenile fishes may actively avoid a large 

spill, planktonic eggs and larvae would be unable to avoid contact. Eggs and larvae of fishes are 

especially vulnerable to oiling because they inhabit the upper layers of the water column, and 

they will die if exposed to certain toxic fractions of spilled oil. Impacts potentially would be 

greater if local-scale currents retained planktonic larval assemblages (and the floating oil slick) 

within the same water mass.

C.5.2 Essential Fish Habitat

Essential Fish Habitat (EFH) is defined as those waters and substrate necessary to fish for 

spawning, breeding, feeding, and growth to maturity. Under the Magnuson-Stevens Fishery 

Conservation and Management Act, as amended, Federal agencies are required to consult on 

activities that may adversely affect EFH designated in Fishery Management Plans developed by 

the regional Fishery Management Councils.

The BOEM (2012b) has reexamined the analysis for fish resources and EFH presented in previous 

lease sale EISs (MMS, 2007a,b), in consideration of the Macondo event. No substantial new 

information was found that would alter the impact conclusions for fish resources and EFH 

presented in the previous MMS lease sale EISs (MMS, 2007a,b).

The Gulf of Mexico Fishery Management Council (GMFMC) has prepared Fishery Management 

Plans for corals and coral reefs, shrimps, stone crab, spiny lobster, reef fishes, coastal migratory 

pelagic fishes, and red drum. In 2005, the EFH for these managed species was redefined in 

Generic Amendment No. 3 to the various Fishery Management Plans (GMFMC, 2005). The EFH 

for most of these GMFMC-managed species is on the continental shelf in waters shallower than 

600 ft (183 m). The shelf edge is the outer boundary for coastal migratory pelagic fishes, reef 

fishes, and shrimps. EFH for corals and coral reefs includes some shelf-edge topographic 

features on the Texas-Louisiana OCS, the nearest of which are in GB 127, located approximately 

119 miles (191 km) north of the lease area along the shelf edge south of Louisiana.

Highly migratory pelagic fishes, which occur as transients in the lease area, are the only 

remaining group for which EFH has been identified in the deepwater Gulf of Mexico. Species in 

this group, including tunas, swordfishes, billfishes, and sharks, are managed by NMFS. Highly 

migratory species with EFH at or near the lease area include the following species and life stages 

(NMFS, 2009):
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• Atlantic bluefin tuna (spawn, eggs, 

larvae)

• Bigeye thresher shark (all)

• Blue marlin (juveniles, adults)

• Longfin mako shark (all)

• Oceanic whitetip shark (all)

• Scalloped hammerhead shark 

(adult)

• Silky shark (all)

• Skipjack tuna (adults and spawn)

• Swordfish (larvae, juveniles)

• Whale shark (all)

• White marlin (juveniles, adults)

• Yellowfin tuna (spawn, juveniles, 

adults)

Recent research indicates the central and western Gulf of Mexico may be important spawning 

habitat for Atlantic bluefin tuna, and NMFS (2009) has designated a Habitat Area of Particular 

Concern (HAPC) for this species. The HAPC covers much of the deepwater Gulf of Mexico, 

including the lease area (Figure 3). The areal extent of the HAPC is approximately 116,000 mi2

(300,000 km2

). The prevailing assumption is that Atlantic bluefin tuna follow an annual cycle of 

foraging in June through March off the eastern U.S. and Canadian coasts, followed by migration 

to the Gulf of Mexico to spawn in April, May, and June (NMFS, 2009).

On 27 May 2011, after an extensive scientific review, NOAA announced that Atlantic bluefin 

tuna currently do not warrant species protection under the ESA. However, NOAA did classify 

the bluefin tuna as a species of concern; however, effectively placing bluefin tuna on a watch list

as the agency awaits new data on the impact of a stricter international management regimen.

A new amendment to the original EFH Generic Amendment was finalized in 2005

(GMFMC, 2005). One of the most significant proposed changes in this amendment reduced the 

extent of EFH relative to the 1998 Generic Amendment by removing the EFH description and 

identification from waters between 100 fathoms and the seaward limit of the Exclusive 

Economic Zone (EEZ). The Highly Migratory Species Fisheries Management Plan was amended 

in 2009 to update EFH and HAPC to include the bluefin tuna spawning area (NMFS, 2009).

There are current NTLs (2009-G39 and 2009-G40) that provide guidance and clarification of the 

regulations with respect to biologically sensitive underwater features and areas and benthic 

communities that are considered EFH (MMS, 2009a,b). A new EFH consultation has been 

initiated between BOEM’s Gulf of Mexico Region and NOAA’s Southeastern Region. Some 

EFH requirements may change with the new agreement. Until the new agreement is in place, 

the 1999 Programmatic Consultation with the elements described above will be followed 

(BOEM, 2012c).

Other HAPCs have been identified by the GMFMC (2005). These include the Florida Middle 

Grounds, Madison-Swanson Marine Reserve, Tortugas North and South Ecological Reserves, 

Pulley Ridge, and several individual reefs and banks of the northwestern Gulf of Mexico

(Figure 3). The nearest HAPC is Jakkula Bank, located approximately 232 miles (373 km) to the 

west-southwest of the lease area.

IPFs potentially affecting EFH include drilling rig presence, noise, and lights; effluent discharges; 

water intakes; and two types of accidents – a small fuel spill and a large oil spill (WCD).
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Impacts of Drilling Rig Presence, Noise, and Lights

The drilling rig, as a floating structure in the deepwater environment, will act as an FAD. In 

oceanic waters, the FAD effect would be most pronounced for epipelagic fishes such as tunas, 

dolphin, billfishes, and jacks, which are commonly attracted to fixed and drifting surface 

structures (Holland et al., 1990; Higashi, 1994; Relini et al., 1994; MMS, 2000, 2007b). This FAD 

effect would possibly enhance feeding of epipelagic predators by attracting and concentrating 

smaller fish species. Because the drilling rig is a single, temporary structure, any impacts on EFH 

for highly migratory pelagic fishes are considered minor.

Impacts of Effluent Discharges

Other effluent discharges affecting EFH by diminishing ambient water quality include drilling 

muds and cuttings, treated sanitary and domestic wastes, deck drainage, and miscellaneous 

discharges such as desalination unit brine and uncontaminated cooling water, fire water, and 

ballast water. Impacts on water quality have been discussed previously. No significant impacts 

on EFH for highly migratory pelagic fishes are expected from these discharges.

Impacts of Water Intakes

As noted previously, cooling water intake will cause entrainment and impingement of plankton, 

including fish eggs and larvae (ichthyoplankton). Due to the limited scope and short duration of 

drilling activities, any short-term impacts on EFH for highly migratory pelagic fishes are not 

expected to be biologically significant.

Impacts of a Small Fuel Spill

The probability of a fuel spill will be minimized by Murphy’s preventative measures during 

routine operations including fuel transfer. In the unlikely event of a spill, implementation of 

Murphy’s OSRP will help diminish the potential for impacts on EFH. Given the open ocean 

location of the lease area, the duration of a small spill and opportunity for impacts to occur 

would be very brief.

Potential spill impacts on EFH are discussed in previous EISs (MMS, 2007b; BOEM, 2012a,b). For 

this EP, there are no unique site-specific issues with respect to spill impacts.

A small fuel spill in offshore waters would produce a slick on the water surface and increase the 

concentrations of petroleum hydrocarbons and their degradation products. The extent and 

persistence of impacts would depend on the meteorological and oceanographic conditions at 

the time and the effectiveness of spill response measures. Section A.9.2 discusses the likely fate 

of a small fuel spill and indicates that over 90% would be evaporated or dispersed naturally 

within 24 hours. The area of the sea surface with diesel fuel on it would range from 1.2 to 12 ac 

(0.5 to 5 ha), depending on sea state and weather conditions.

A small fuel spill could have localized impacts on EFH for highly migratory pelagic fishes, 

including tunas, swordfishes, billfishes, and sharks. These species occur as transients in the 

lease area. A spill would also produce short-term impact on water quality in the HAPC for 

spawning bluefin tuna, which covers much of the deepwater Gulf of Mexico. The areal extent of 

the affected area would represent a negligible portion of the HAPC.
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A small fuel spill would not affect EFH for corals and coral reefs, the nearest EFH being the 

topographic features located approximately 35 miles (56 km) northwest of the lease area along 

the shelf edge south of Louisiana. A small fuel spill would float and dissipate on the sea surface 

and would not contact these features.

Impacts of a Large Oil Spill (WCD)

Potential spill impacts on EFH are discussed in previous EISs (MMS, 2007b; BOEM, 2012a,b). For 

this EP, there are no unique site-specific issues with respect to EFH.

An oil spill in offshore waters would temporarily increase hydrocarbon concentrations on the 

water surface and potentially in the subsurface as well. Given the extent of EFH designations in 

the Gulf of Mexico (GMFMC, 2005; NMFS, 2009), some impact on EFH would be unavoidable.

A large spill could affect the EFH for many managed species including shrimps, stone crab, spiny 

lobster, reef fishes, coastal migratory pelagic fishes, and red drum. It would result in adverse 

impacts on water quality and water column biota including phytoplankton, zooplankton, and 

nekton. In coastal waters, sediments could be contaminated and result in persistent 

degradation of the seafloor habitat for managed demersal fish and shellfish species.

The lease area is within the HAPC for spawning Atlantic bluefin tuna (NMFS, 2009). A large spill 

could temporarily degrade the HAPC due to increased hydrocarbon concentrations in the water 

column, with the potential for lethal or sublethal impacts on spawning tuna. Potential impacts 

would depend in part on the timing of a spill, as this species migrates to the Gulf of Mexico to 

spawn in April, May, and June (NMFS, 2009).

The distance to the boundary of the designated EFH area under the corals and coral reefs 

management plan is approximately 35 miles (56 km) from the lease area. An accidental spill 

would be unlikely to affect this area, since a surface slick would not reach these features due to 

their depth.

C.6 Archaeological Resources

C.6.1 Shipwreck Sites

The BOEM (2012b) reexamined the analyses for archaeological resources presented in 

MMS (2007b) based on additional information available since its publication and in 

consideration of the Macondo oil spill. Substantial new information that alters the impact 

conclusion for archaeological resources presented in MMS (2007b) has come to light as a result 

of BOEM-sponsored studies and industry surveys. Specifically, evidence of damage to significant 

cultural resources (i.e., historic shipwrecks) has been shown to have occurred because of an 

incomplete knowledge of seafloor conditions in lease areas >200 m (656 ft) deep that have been 

exempted from high-resolution surveys. Since significant historic shipwrecks have recently been 

discovered outside the previously designated high-probability areas (some of which show 

evidence of impacts from permitted activities prior to their discovery), a survey is now required 

for exploration and development projects.

The lease area is not on the list of OCS blocks with a high potential for historic shipwrecks

(BOEM, 2012d). Ten sonar contacts interpreted as unidentified debris on the seafloor were 

detected in DC 178. One of these contacts lie within 2,000 ft (610 m) of proposed Well A and is 
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believed to be man-made debris; a 100’ geohazard avoidance zone will be applied. There were 

no indications of wrecks or other archaeological resources detected during the site clearance 

survey (GEMS, 2013). Murphy will abide by the applicable requirements of NTL 2005-G07, 

which stipulates that work be stopped at the project site if any previously undetected 

archaeological resource is discovered after work has begun until appropriate surveys and 

evaluations have been completed.

Because there are no shipwreck sites in the lease area, there are no routine IPFs that are likely 

to affect shipwrecks. Impacts of a large oil spill (WCD) are the only IPFs considered. A small fuel 

spill would not affect shipwrecks because the oil would float and dissipate on the sea surface.

Impacts of a Large Oil Spill (WCD)

MMS (2007b) estimated that a severe subsurface blowout could resuspend and disperse 

sediments within a 300-m (984-ft) radius. Because there are no historic shipwrecks in the lease 

area, this impact would not be relevant.

Previous analyses (MMS, 2007a) concluded that oil spills would be unlikely to affect 

archaeological sites beyond the immediate vicinity of the wellhead (i.e., due to physical impacts 

of a blowout) because the oil would rise quickly to the sea surface directly over the spill location. 

However, during the Macondo spill, subsurface plumes were reported at a water depth of about 

3,600 ft (1,100 m), extending at least 22 miles (35 km) from the wellsite and persisting for more 

than a month (Camilli et al., 2010). The subsurface plumes apparently resulted from the use of 

dispersants at the wellhead (Joint Analysis Group, 2010c). While the behavior and impacts of 

subsurface plumes are not well known, a subsurface plume could have the potential to contact 

shipwreck sites beyond the 300-m (984-ft) radius estimated by MMS (2007a), depending on its 

extent, trajectory, and persistence. If oil from a subsea spill should come into contact with 

wooden shipwrecks on the seafloor, it could adversely affect their condition or preservation. 

Should there be any indication that potential shipwreck sites could be affected, in accordance 

with NTL 2005-G07 Murphy will immediately halt operations, take steps to ensure that the site 

is not disturbed in any way, and contact the BOEM Regional Supervisor, Leasing and 

Environment, within 48 hours of its discovery. Murphy would cease all operations within 

1,000 ft (305 m) of the site until the Regional Supervisor provides instructions on steps to take 

to assess the site’s potential historic significance and protect it.

A spill entering shallow coastal waters could conceivably contaminate an undiscovered 

shipwreck site. As noted by MMS (2007b), should an oil spill contact a coastal historic site, such 

as a fort or a lighthouse, the major impact would be a temporary, reversible visual impact from 

oil contact and contamination of the site and its environment. However, more recent studies 

suggest that the impacts could be longer term and not easily reversible (BOEM, 2012b).

C.6.2 Prehistoric Archaeological Sites

Available evidence suggests that sea level in the northern Gulf of Mexico was at least 300 ft 

(91 m), and possibly as much as 427 ft (130 m), lower than present sea level during the period 

20,000 to 17,000 years Before Present (B.P.) (Nelson and Bray, 1970). Sea level in the northern 

Gulf reached its present stand around 3,500 years B.P. (Pearson et al., 1986).

During periods that the continental shelf was exposed above sea level, the area was open to 

habitation by prehistoric peoples. The advent of early man into the Gulf of Mexico region is 
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currently accepted to be around 12,000 years B.P. (Aten, 1983). The sea-level curve for the 

northern Gulf of Mexico proposed by Coastal Environments, Inc. (CEI) suggests that sea level at 

12,000 years B.P. would have been approximately 148 to 197 ft (45 to 60 m) below the 

present-day sea level (CEI, 1977, 1982). On this basis, the continental shelf shoreward of the 

45- to 60-m (148- to 197-ft) bathymetric contours has potential for prehistoric sites dating after 

12,000 years B.P. Because of inherent uncertainties in both the depth of sea level and the entry 

date of prehistoric man into North America, the MMS adopted the 60-m (197-ft) water depth as 

the seaward extent for archaeological site potential in the Gulf of Mexico region.

With a water depth between 6,567 to 6,580 ft (2,002 to 2,006 m), the lease area is well beyond 

the 60-m (197-ft) depth contour used by the BOEM as the seaward extent for prehistoric 

archaeological site potential in the Gulf of Mexico. Because prehistoric archaeological sites are 

not found in the lease area, the only relevant IPF is a large oil spill (WCD). A small fuel spill 

would not affect prehistoric archaeological resources because the oil would float and dissipate 

on the sea surface.

Impacts of a Large Oil Spill (WCD)

Because prehistoric archaeological sites are not found in the lease area, they would not be 

affected by the physical effects of a subsea blowout. The MMS (2007b) estimates that a severe

subsurface blowout could resuspend and disperse sediments within a 300-m (984-ft) radius.

Along the northern Gulf Coast, prehistoric sites occur frequently along the barrier islands and 

mainland coast and along the margins of bays and bayous (MMS, 2007b). If a spill did reach a 

prehistoric site along these shorelines it could coat fragile artifacts or site features and 

compromise the potential for radiocarbon dating organic materials in a site (although other 

dating methods are available and it is possible to decontaminate an oiled sample for 

radiocarbon dating). Coastal prehistoric sites could also be damaged by spill cleanup operations 

(e.g., by destroying fragile artifacts and disturbing the provenance of artifacts and site features).

C.7 Coastal Habitats and Protected Areas

Coastal habitats in the northeastern Gulf of Mexico that may be affected by oil and gas activities 

are described in recent EISs (MMS, 2007b; BOEM, 2012a,b,c) and in a literature review by 

Collard and Way (1997). Coastal habitats inshore of the project area include barrier beaches 

and dunes, wetlands, and submerged seagrass beds. Generally, most of the northeastern Gulf is 

fringed by barrier beaches, with wetlands and/or submerged seagrass beds occurring in 

sheltered areas behind the barrier islands and in estuaries.

Due to the distance from shore, the only IPF associated with routine activities in the lease area 

that potentially may affect beaches and dunes, wetlands, seagrass beds, coastal wildlife refuges, 

wilderness areas, or any other managed or protected coastal area relate to support vessel 

traffic. The support bases at Port Fourchon and Houma, Louisiana, are not in wildlife refuges or 

wilderness areas. Potential impacts of support vessel traffic are addressed briefly below.

A small fuel spill in the lease area would be unlikely to affect coastal habitats, as the lease area is 

75 miles (121 km) from the nearest shoreline (Louisiana). As explained in Section A.9.2, a small 

fuel spill would not be expected to make landfall or reach coastal waters prior to breaking up. 

Potential impacts of a large oil spill (WCD) are discussed below. 
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Impacts of Support Vessel Traffic

For OCS activities in general, support operations, including crew boats and supply boats, may 

have a minor incremental impact on coastal habitats. Over time with a large number of vessel 

trips, vessel wakes can erode shorelines along inlets, channels, and harbors. Support 

operations, including crew boats and supply boats, may have a minor incremental impact on 

coastal habitats or protected areas. Impacts will be minimized by following the speed and wake 

restrictions in harbors and channels.

Impacts of a Large Oil Spill (WCD)

Potential spill impacts on coastal habitats are discussed in recent EISs (MMS, 2007b; BOEM, 

2012a,b,c). Coastal habitats inshore of the project area include barrier beaches and dunes, 

wetlands, and submerged seagrass beds. For this EP, there are no unique site-specific issues 

with respect to coastal habitats.

The revised OSRA modeling summarized in Table 3 predicts that coastal areas of Plaquemines 

and St. Bernard Parishes, Louisiana; Jackson County, Mississippi, Baldwin and Mobile Counties, 

Alabama; and Escambia County, Florida, are the most likely to be affected within 120 days 

during various seasons. Plaquemines Parish has the greatest probability of contact in winter 

(23%), summer (25%), and fall (28%). In spring both Mobile and Baldwin Counties, Alabama, 

have the highest probability (17%) of contact.

The shorelines within the geographic range predicted by the OSRA modeling (Table 3) include 

extensive barrier beaches and wetlands, with submerged seagrass beds occurring in sheltered 

areas behind the barrier islands and in estuaries. NWRs and other protected areas along the 

coast are discussed in a recent lease sale EIS (MMS, 2003, 2007b) and Murphy’s OSRP. Coastal 

and near coastal wildlife refuges, wilderness areas, and state and national parks within the 

geographic range of the potential shoreline contacts after 120 days include the following:

• Pointe Au Chien Wildlife Management 

Area (WMA)

• Wisner WMA

• Salvador WMA

• Jean Lafitte National Historical Park 

and Preserve

• Delta NWR

• Pass a Loutre WMA

• Breton NWR

• St. Bernard State Park

• Biloxi WMA

• Bayou Savage NWR

• Hancock County Marsh Coastal 

Reserve

• Buccaneer State Park

• Jourdan River Coastal Reserve

• Biloxi River Coastal Reserve

• Gulf Islands National Seashore

• Bayou Sauvage NWR

• Big Branch Marsh NWR

• Pearl River WMA

• Wolf River Coastal Reserve

• Grand Bayou Coastal Preserve

• Bayou Portage Coastal Reserve

• Biloxi Marshes State Coastal Preserve

• Deer Island State Coastal Preserve

• Gulf Islands National Seashore

• Davis Bayou Coastal Preserve

• Mississippi Sandhill Crane NWR

• Pascagoula River Coastal Reserve

• Grand Bay National Estuarine 

Research Reserve

• Grand Bay NWR

• Grand Bay Savannah Coastal Preserve

• Deer Island State Coastal Preserve

• Old Fort Bayou Coastal Reserve

• Bellefontaine Point Coastal Reserve

• Graveline Bay Coastal Reserve
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• The Grand Bay Savanna Tract

• Penalver State Park

• Bon Secour NWR

• W.L. Holland WMA

• Meaher State Park

• Weeks Bay National Estuarine 

Research Reserve

• Gulf State Park

• Lillian Swamp Mitigation Area

• Tarkiln Bayou State Preserve

• Perdido Key State Recreation Area

• Big Lagoon State Recreation Area

• Fort Pickens State Park Aquatic 

Preserve

• Pensacola Bay SWIM Area

• Yellow River WMA

• Choctawatchee Bay SWIM Area

• Henderson State Park

• Point Washington Outstanding Florida

Water

• Deer Lake State Park

• Grayton Beach State Park Outstanding 

Florida Water

• St. Andrew Bay Watershed SWIM Area

• St. Andrews State Park Aquatic 

Preserve

• St Andrews State Park

• St Joseph Peninsula State Park

• St. Joseph Bay State Buffer Preserve

• St. Vincent NWR

• Apalachicola National Estuarine 

Research Reserve

• Apalachicola Bay Aquatic Preserve 

Outstanding Florida Water

• Apalachicola River and Bay SWIM Area

• Apalachicola River Wildlife and 

Environmental Area

• St. George Island State Park

The level of impacts from oil spills on coastal habitats depends on many factors, including the oil 

characteristics, the geographic location of the landfall, and the weather and oceanographic 

conditions at the time (MMS, 2007b). Oil that makes it to beaches may be either liquid 

weathered oil, an oil-and-water mousse, or tarballs (MMS, 2007b). Oil is generally deposited on 

beaches in lines defined by wave action at the time of landfall. Oil that remains on the beach 

will thicken as its volatile components are lost. Thickened oil may form tarballs or aggregations 

that incorporate sand, shell, and other materials into its mass. Tar may be buried to varying 

depths under the sand. On warm days, both exposed and buried tarballs may liquefy and ooze. 

Oozing may also serve to expand the size of a mass as it incorporates beach materials. Oil on 

beaches may be cleaned up manually, mechanically, or both. Some oil can remain on the beach 

at varying depths and may persist for several years as it slowly biodegrades and volatilizes.

Wetlands are highly sensitive to oiling. The MMS (2007b) predicted that for every 50 bbl of oil 

contacting wetlands, approximately 6.7 ac (2.7 ha) of wetland vegetation will experience 

dieback. Thirty percent of these damaged wetlands are assumed to recover within 4 years, and 

85% within 10 years. About 15% of the contacted wetlands are expected to be converted 

permanently to open-water habitat. The critical concentration of oil is that concentration above 

which impacts to wetlands will be long-term and recovery will take longer than two growing 

seasons, and which causes plant mortality and some permanent wetland loss. Critical 

concentrations of various oils are expected to vary broadly for wetland types and wetland plant 

species. Louisiana wetlands are assumed to be more sensitive to oil contact than elsewhere in 

the Gulf because of high cumulative stress (MMS, 2007b). In addition to the direct impacts of 

oil, cleanup activities in marshes may accelerate rates of erosion and retard recovery rates, 

which have been reported to require from years to decades following a spill (MMS, 2007b; 

BOEM, 2012c).
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C.8 Socioeconomic and Other Resources

C.8.1 Recreational and Commercial Fishing

BOEM has reexamined the analysis for recreational and commercial fishing presented in 

MMS (2007b) based on additional information and in consideration of the Macondo spill. No 

new information was found that would alter the potential impacts on commercial fishing

(BOEM, 2012c).

The main commercial fishing activity in deep waters of the northern Gulf of Mexico is pelagic 

longlining for tunas, swordfishes, and other billfishes (Continental Shelf Associates, Inc., 2002). 

Pelagic longlining has occurred historically in the project area, primarily during spring and 

summer. In August 2000, the Federal government closed two areas in the northeastern 

Gulf of Mexico to longline fishing (65 FR 47214, 1 August 2000). The lease is outside of the 

closure areas.

Longline gear consists of monofilament line deployed from a moving vessel and generally 

allowed to drift for 4 to 5 hours (Continental Shelf Associates, Inc., 2002). As the mainline is put 

out, baited leaders and buoys are clipped in place at regular intervals. It takes 8 to 10 hours to 

deploy a longline and about the same time to retrieve it. Longlines are often set near 

oceanographic features such as fronts or downwellings, with the aid of sophisticated on-board 

temperature sensors, depth finders, and positioning equipment. Vessels typically are 33 to 98 ft

(10 to 30 m) long, and their trips last from about 1 to 3 weeks. The main Gulf of Mexico 

homeports for longlining vessels are in Louisiana (Dulac and Venice) and Florida (Destin, 

Madeira Beach, and Panama City).

It is unlikely that any commercial fishing activity other than longlining occurs at or near the 

project area. Benthic species targeted by commercial fishers occur on the upper continental 

slope, well inshore of the project area. Royal red shrimp (Pleoticus robustus) are caught by 

trawlers in water depths of about 820 to 1,804 ft (250 to 550 m). Tilefishes (primarily 

Lophalotilus chamaeleonticeps) are caught by bottom longlining in water depths from about 

540 to 1,476 ft (165 to 450 m) (Continental Shelf Associates, Inc., 2002).

Most recreational fishing activity in the region occurs in water depths less than 200 m (656 ft)

(Continental Shelf Associates, Inc., 1997, 2002). In deeper water, the main attraction to 

recreational fishers would be petroleum rigs offshore Texas and Louisiana. Due to the distance 

from shore, it is unlikely that recreational fishing activity is occurring in the lease area.

The only routine IPF potentially affecting fisheries is drilling rig presence (including noise and 

lights). Two types of potential accidents are also addressed below – a small fuel spill and a large 

oil spill (WCD).

Impacts of Drilling Rig Presence

There is a slight possibility of pelagic longlines becoming entangled in the drilling rig. For 

example, in January 1999 a portion of a pelagic longline snagged on the acoustic Doppler 

current profiler of a drillship working in the Gulf of Mexico (Continental Shelf Associates, Inc., 

2002). The line was removed without incident. Generally, longline fishers use radar and are 

aware of offshore structures and ships when placing their sets. Therefore, little or no impact on 

pelagic longlining is expected.
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Because it is unlikely that any recreational fishing activity is occurring in the project area, no 

adverse impacts are anticipated. Other factors such as effluent discharges are likely to have 

negligible impacts on commercial or recreational fisheries due to rapid dispersion, the small 

area of ocean affected, and the intermittent nature of the discharges.

Impacts of a Small Fuel Spill

The probability of a fuel spill will be minimized by Murphy’s preventative measures during 

routine operations including fuel transfer. In the unlikely event of a spill, implementation of 

Murphy’s OSRP will potentially mitigate and reduce the potential for impacts. Given the open 

ocean location of the lease area, the duration of a small spill and opportunity for impacts to 

occur would be very brief.

Pelagic longlining activities in the lease area, if any, could be interrupted in the event of a small 

fuel spill. The area of the sea surface with diesel fuel on it would range from 1.2 to 12 ac (0.5 to 

5 ha), depending on sea state and weather conditions. Fishing activities could be interrupted 

due to the activities of response vessels operating in the lease area. A small fuel spill would not 

affect coastal water quality because the spill would not be expected to make landfall or reach 

coastal waters prior to breaking up (see Section A.9.2).

Impacts of a Large Oil Spill (WCD)

Potential spill impacts on fishing activities are discussed in previous EISs (MMS, 2007b; BOEM, 

2012b,c). For this EP, there are no unique site-specific issues with respect to this activity.

Pelagic longlining activities in the lease area and other fishing activities in the northern 

Gulf of Mexico could be interrupted in the event of a large oil spill. A spill may or may not result 

in fishery closures, depending on the duration of the spill, the oceanographic and 

meteorological conditions at the time, and the effectiveness of spill response measures. The 

recent Macondo spill provides information about the maximum potential extent of fishery 

closures in the event of a large oil spill in the Gulf of Mexico (NMFS, 2010c). At its peak on 

12 July 2010, closures encompassed 84,101 mi2 (217,821 km2

), or 34.8% of the 

U.S. Gulf of Mexico EEZ.

C.8.2 Public Health and Safety

There are no IPFs associated with routine operations that are expected to affect public health 

and safety. Impacts of a small fuel spill and a large oil spill (WCD) are addressed below.

Impacts of a Small Fuel Spill

The probability of a fuel spill will be minimized by Murphy’s preventative measures during 

routine operations including fuel transfer. In the unlikely event of a spill, implementation of 

Murphy’s OSRP will potentially alleviate the potential for impacts. EP Attachment Q provides

detail on spill response measures.

A small fuel spill would not have any impacts on public health and safety because it would affect 

only a small area of the open ocean 75 miles (121 km) from the nearest shoreline (Louisiana)

and nearly all of the diesel fuel would evaporate or disperse naturally within 24 hours. 

Response crews would be equipped with appropriate safety equipment to avoid injury and 
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health effects. A small fuel spill would not be expected to make landfall or reach coastal waters 

prior to breaking up (see Section A.9.2).

Impacts of a Large Oil Spill (WCD)

In the event of a large spill from a blowout, the main safety and health concerns are those of the 

offshore personnel involved in the incident and those responding to the spill. The drilling rig 

maintains a Shipboard Oil Pollution Emergency Plan as required under MARPOL 73/78.

Depending on the spill rate and duration, the physical/chemical characteristics of the oil, 

meteorological and oceanographic conditions at the time, and the effectiveness of spill response 

measures, the public could be exposed to oil on the water and along the shoreline, including 

skin contact or breathing VOCs. Crude oil is a highly flammable material, and any smoke or 

vapors from a crude oil fire can cause irritation, and in large quantities may pose a health 

hazard.

Data from the recent Macondo spill provide relevant information about the types of health 

issues that may occur in the event of a large oil spill (Centers for Disease Control and Prevention, 

2010a). Wildlife cleaning and rehabilitation workers have reported concerns including scrapes 

and cuts, itchy or red skin or rash, and symptoms of headache or feeling faint, dizzy, or fatigued. 

Hand, shoulder, or back pain was also reported by some wildlife-cleaning workers. Personnel 

working on offshore vessels or providing direct oversight to offshore vessels, including 

USCG personnel, civilian contractors, and other responders who were exposed to oil and 

dispersants, had a 7 to 12 times higher prevalence of upper respiratory symptoms and cough 

than those not exposed (Centers for Disease Control and Prevention, 2010b). Another potential 

occupational hazard for spill response workers in general was heat stress from work in a hot and 

humid environment. Initial symptoms from cleanup workers who sought medical care in 

Louisiana were typical of acute exposure to hydrocarbons or H2S, e.g., headaches, dizziness, 

nausea, vomiting, cough, respiratory distress, and chest pain (Solomon and Janssen, 2010).

C.8.3 Employment and Infrastructure

There are no IPFs associated with routine operations that are expected to affect employment 

and infrastructure. The project involves drilling with support from existing shorebase facilities in 

Louisiana. No new or expanded facilities will be constructed, and no new employees are 

expected to move permanently into the area. The project will have a negligible impact on 

socioeconomic conditions such as local employment, existing offshore and coastal infrastructure 

(including major sources of supplies, services, energy, and water), and minority and lower 

income groups. Impacts of a small fuel spill and a large oil spill (WCD) are addressed below.

Impacts of a Small Fuel Spill

The probability of a fuel spill will be minimized by Murphy’s preventative measures during 

routine operations including fuel transfer. In the unlikely event of a spill, implementation of 

Murphy’s OSRP will potentially mitigate and reduce the potential for impacts. Given the open 

ocean location of the lease area, the duration of a small spill and opportunity for impacts to 

occur would be very brief.

A small fuel spill that is dissipated within a few days would have little or no economic impact, as 

the spill response would use existing facilities, resources, and personnel.
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Impacts of a Large Oil Spill (WCD)

Potential socioeconomic impacts of an oil spill are discussed in recent EISs (MMS, 2007b; BOEM, 

2012b,c). For this EP, there are no unique site-specific issues with respect to employment and 

coastal infrastructure. A large spill could cause economic impacts in several ways: it could result 

in extensive fishery closures that put fishermen out of work; it could result in temporary 

employment as part of the response effort; it could result in adverse publicity that affects 

employment in coastal recreation and tourism industries; and it could result in another 

suspension of OCS drilling activities, including service and support operations that are an 

important part of local economies.

In addition to the analyses presented by MMS (2007b) and BOEM (2012b), a recent study 

explored the economic impacts of the Macondo spill on oil and gas industry employment due to 

suspension of deepwater drilling (Inter-Agency Economic Report, 2010). The study indicates 

that during the moratorium, the number of oil industry workers in the Gulf of Mexico fell by 

about 2,000 and may have indirectly caused a temporary loss of 8,000 to 12,000 jobs along the 

Gulf Coast. Total spending by drilling operators is estimated to have declined by $1.8 billion 

over a six-month period; this direct reduction in spending affected employment in the industries 

that supply the Gulf drilling industry and in all other industries affected by declines in consumer 

and business spending (Inter-Agency Economic Report, 2010).

C.8.4 Recreation and Tourism

BOEM has reexamined the analyses for recreation and tourism presented in MMS (2007b) based 

on additional information and in consideration of the Macondo oil spill event. No new 

information was found that would alter the potential impacts on recreation and tourism 

(BOEM, 2012c).

There are no known recreational uses of the lease area. Recreational resources and tourism in 

coastal areas would not be affected by any routine activities due to the distance from shore. 

Compliance with NTL 2012-BSEE-G01 will minimize the chance of trash or debris being lost 

overboard from the drilling rig and subsequently washing up on beaches. Potential impacts of a 

small fuel spill and a large oil spill (WCD) are addressed below.

Impacts of a Small Fuel Spill

The probability of a fuel spill will be minimized by Murphy’s preventative measures during 

routine operations including fuel transfer. In the unlikely event of a spill, implementation of 

Murphy’s OSRP will potentially help mitigate and reduce the potential for impacts. Given the 

open ocean location of the lease area, the duration of a small spill and opportunity for impacts 

to occur would be very brief.

A small fuel spill in the lease area would be unlikely to affect recreation and tourism. There are 

no known recreational or tourism activities occurring in the lease area, and as explained in 

Section A.9.2, a small fuel spill would not be expected to make landfall or reach coastal waters 

prior to breaking up.
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Impacts of a Large Oil Spill (WCD)

Potential impacts of an oil spill on recreation and tourism are discussed in recent EISs 

(MMS, 2007b; BOEM, 2012b). For this EP, there are no unique site-specific issues with respect 

to these impacts.

Impacts on recreation and tourism would vary depending on the duration of the spill and its fate 

including the effectiveness of response measures. A large spill that reached coastal waters and 

shorelines could adversely affect recreation and tourism by contaminating beaches and 

wetlands, resulting in negative publicity that encourages people to stay away. Based on the 

revised OSRA modeling (BOEM, 2012c) as summarized in Section A.9.3 (Table 3), Plaquemines 

and St. Bernard Parishes, Louisiana; Mobile and Baldwin Counties, Alabama; and Jackson, 

Mississippi, are the areas most likely to be contacted by a spill. However, other shorelines from 

Cameron, Texas to Dade, Florida could also be contacted to a lesser extent. These areas include 

popular beaches and recreational sites along the coast. It is not known whether other, more 

distant coastal areas could be affected if an oil spill persisted for more than 120 days.

In addition to the analysis presented by MMS (2007b), recent and ongoing studies have 

explored the economic impacts of the Macondo spill including tourism and "brand" damage 

(IEM, 2010; Oxford Economics, 2010). The U.S. Travel Association has estimated the economic 

impact of the Macondo spill on tourism across the Gulf Coast over a three-year period at 

$22.7 billion (Oxford Economics, 2010).

C.8.5 Land Use

Land use along the northern Gulf Coast is discussed in recent lease sale EISs (MMS, 2007b; 

BOEM, 2012b,c). There are no routine IPFs potentially affecting land use. The project will use 

existing onshore support facilities in Louisiana. The land use at the existing shorebase sites is 

industrial. The project will not involve any new construction or changes to existing land use and, 

therefore, will not have any impacts. Levels of boat and helicopter traffic, as well as demand for 

goods and services including scarce coastal resources, will represent a small fraction of the level 

of activity occurring at the shorebases.

A large oil spill (WCD) is the only relevant IPF. A small fuel spill would not have any impacts on 

land use, as the response would be staged out of existing shorebases and facilities.

Impacts of a Large Oil Spill (WCD)

The initial response for a large oil spill would be staged out of existing facilities, with no effect on 

land use. A large spill could have limited temporary impacts on land use along the coast if 

additional staging areas were needed. For example, during the Macondo spill, temporary 

staging areas were established in Louisiana, Mississippi, Alabama, and Florida for spill response 

and cleanup efforts. In the event of a large spill in the lease area, similar temporary staging 

areas could be needed. These areas would eventually return to their original use as the 

response is demobilized.

C.8.6 Other Marine Uses

The lease area is not located within any USCG-designated fairway or shipping lane. The

proposed surface disturbances in DC 178 are located within Military Warning Areas W-155C 

(Wells A and B) and EWTA-1 (Well C). Therefore, in accordance with the requirements of the 
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Military Areas stipulation, Murphy will contact the Fleet Area Control and Surveillance in order 

to coordinate and control the electromagnetic emissions during the proposed operations. The 

electromagnetic emissions section of the stipulation requires the operator and its agents to

reduce and curtail the use of radio or other equipment emitting electromagnetic energy within 

some areas. This serves to reduce the impact of oil and gas activity on the communications of 

military missions and reduces the possible effects of electromagnetic energy transmissions on 

missile testing, tracking, and detonation.

Additionally, the location of the proposed activities are outside of the 100-mile (160-km) buffer 

line for the drilling window areas and approximately 50 miles (80 km) east of the military 

mission line. There are no other known marine uses of the lease area.

There are no IPFs from routine project activities that are likely to affect other marine uses of the 

lease area. A large oil spill (WCD) is the only relevant accident IPF. A small fuel spill would not 

have any impacts on other marine uses because spill response activities would be mainly within 

the lease area and the duration would be brief.

Impacts of a Large Oil Spill (WCD)

An accidental spill would be unlikely to significantly affect shipping or other marine uses. The 

block is not located within any USCG-designated fairway or shipping lane. In the event of a large 

spill requiring numerous response vessels, coordination would be required to manage the vessel 

traffic for safe operations. Murphy will comply with BOEM requirements and lease stipulations 

to avoid impacts on uses of the area by military vessels and aircraft.

D. Environmental Hazards

D.1 Geologic Hazards

The site clearance surveys conducted by GEMS (2013) concluded that the wellsites are free of 

any significant geological hazards and are suitable for the proposed activities. See Attachment H 

of the EP for supporting geological and geophysical information.

D.2 Severe Weather

Under most circumstances, weather is not expected to have any effect on the proposed 

activities. Extreme weather, including high winds, strong currents, and large waves, was 

considered in the design criteria for the drilling rigs under consideration for this project. High 

winds and limited visibility during a severe storm could disrupt support activities (vessel and 

helicopter traffic) and make it necessary to suspend some activities on the drilling rig for safety 

reasons until the storm or weather event passes. In the event of a hurricane, procedures as 

outlined in the Hurricane Evacuation Plan would be adhered to.

D.3 Currents and Waves

Metocean conditions such as sea states, wind speed, ocean currents, etc. will be continuously 

monitored. Under most circumstances, physical oceanographic conditions are not expected to 

have any effect on the proposed activities. Strong currents (e.g., caused by Loop Current eddies 
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and intrusions) and large waves were considered in the design criteria for the drilling rigs under 

consideration for this project. High waves during a severe storm could disrupt support activities 

(i.e., vessel and helicopter traffic) and make it necessary to suspend some activities on the 

drilling rig for safety reasons until the storm or weather event passes.

E. Alternatives

No formal alternatives were evaluated in this EIA for an EP. However, various technical and 

operational options, including the location of the wellsites and the selection of a drilling unit, 

were considered by Murphy in developing the proposed action.

F. Mitigation Measures

The proposed action includes numerous mitigation measures required by laws, regulations, and 

BOEM lease stipulations and NTLs. The project will comply with all applicable Federal, State, 

and local requirements concerning air pollutant emissions, discharges to water, and solid waste 

disposal. All project activities will be conducted under guidance by Murphy’s OSRP and will 

include the measures described in EP Section H.

G. Consultation

No persons or agencies were consulted during the preparation of this EIA.

H. Preparers

The EIA was prepared by CSA Ocean Sciences Inc. Contributors included

• Carlyle Kalloo (Senior Scientist);

• Deborah Fawcett, M.S. (Project Scientist 2);

• Neal Phillips, Ph.D. (Senior Scientist);

• Keith VanGraafeiland (GIS/Remote Sensing Specialist);

• Kristen L. Metzger (Library and Information Services Director); and

• Pamela Jones (Technical Editor).
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