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Suggested Citation:"1. Introduction." National Research Council. 1992. Assessment of the U.S. Outer Continental Shelf Environmental Studies Program: II. Ecology. Washington, DC: The National Academies Press. doi: 10.17226/1963.
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1

Introduction

OUTER CONTINENTAL SHELF ACTIVITIES

Magnitude and Management

Leasing of oil and gas resources on the OCS is managed by the Department of the Interior (DOI) Minerals Management Service (MMS). MMS was formed in 1982 as a result of DOI Secretary James Watt's desire to consolidate responsibility for offshore oil and gas development in one agency. MMS includes some functions and personnel previously in the Bureau of Land Management (BLM) and the U.S. Geological Survey (USGS). Federal responsibility for development of mineral resources and conservation of natural resources on the OCS was established by the Outer Continental Shelf Lands Act (OCSLA) (67 State 462) of 1953, the Submerged Lands Act (67 State 29) of 1953, and the OCSLA amendments of 1978.

From 1954, when the oil and gas leasing program began, through 1989, the last year for which statistics have been published, federal offshore oil and gas development has provided almost 8% (8.2 billion bbl) of total domestic oil production, about 14% (83 trillion cubic feet) of domestic natural gas, and over $93 billion in revenue from cash bonuses, lease rental payments, and royalties on produced oil and gas (MMS, 1990a,b). In 1988 alone, the OCS provided approximately 10.8% of the domestic oil produced, 24.6% of domestic natural gas, and over $3 billion in revenue (MMS, 1990b). From 1954 through 1989, there were 102 lease sales; they offered 138,726 tracts that included 756,033,873 acres. Only 11,513 (8.3%) of those tracts, which included 59,316,001 acres (i.e., 7.8% of the acreage offered), were actually leased. Table 1-1 provides a regional breakdown of lease offerings and sales in 1954-1989. Table 1-2 shows, by region, the number of leases active in 1989.

In 1974, as part of a strategy to deal with the nation's energy problems after the Arab oil embargo, President Nixon directed the Secretary of the Interior to increase the amount of acreage leased. Congress was concerned, however, that federal administration of the leasing program and federal regulation of OCS development constituted a closed decision-making process involving the Secretary of the Interior and industry (Congressional and Administrative News of the U.S. Code, 1978). At the time the amendments to the OCSLA were passed, Congress expected that offshore production would provide the largest domestic source of oil and gas into the 1990s (Congressional and Administrative News of the U.S. Code, 1978). One purpose of the amendments was to provide a statutory mechanism for public participation in decision-making to increase public confidence in this government activity (Congressional and Administrative News of the U.S. Code, 1978).

Suggested Citation:"1. Introduction." National Research Council. 1992. Assessment of the U.S. Outer Continental Shelf Environmental Studies Program: II. Ecology. Washington, DC: The National Academies Press. doi: 10.17226/1963.
×

TABLE 1-1 Lease Offerings and Sales, 1954-1989

 

Leases Offered

Leases Issued

Leased Percentage

Region

Number of Sales

Tracts

Acres

Tracts

Acres

Tracts

Acres

Alaska

15

17,766

98,013,764

1,481

8,181,465

8.3

8.3

Atlantic

8

9,160

51,520,602

410

2,334,205

4.5

4.5

Gulf of Mexico

68

109,897

596,676,112

9,152

46,260,319

8.3

7.7

Pacific

11

1,903

9,823,395

470

2,540,012

24.7

25.9

TOTALS

102

138,726

756,033,873

11,513

59,316,001

8.3

7.8

Source: MMS, 1990a.

TABLE 1-2 Active Leases, 1989

Region

Active Leases

Percentage of Active Leases

Acres Leased

Percentage of Acres Leased

Alaska

938

14.7

5,168,479

15.7

Atlantic

71

1.1

404,216

1.2

Gulf of Mexico

5,228

82.1

26,671,953

81.0

Pacific

130

2.1

671,752

2.1

TOTALS

6,367

100.0

32,916,400

100.0

Source: MMS, 1990b.

The OCS lease-sale schedule is established in accordance with a 5-year plan that sets forth the size, timing, and location of proposed leasing activities. The plan is developed in a 2-year process that includes consultation with coastal states and other federal agencies and an opportunity for public comment. Beginning in 1983, lease sales were offered on an areawide basis, instead of for selected tracts, so the numbers of blocks and leases were increased and more exploratory wells were encouraged in frontier areas (areas with no oil and gas production), such as areas of deep water. The current plan, effective from mid-1987 to mid-1992, calls for one sale every 3 years in each of 21 of the 26 OCS planning areas (see Fig. 1-1 and Fig.1-2), except in the Gulf of Mexico, where sales are annual. Sales in several environmentally sensitive subareas have been deferred indefinitely (MMS, 1987a). Since 1987, additional deferrals, cancellations, and leasing moratoria have occurred.

Suggested Citation:"1. Introduction." National Research Council. 1992. Assessment of the U.S. Outer Continental Shelf Environmental Studies Program: II. Ecology. Washington, DC: The National Academies Press. doi: 10.17226/1963.
×

FIGURE 1-1 Outer Continental Shelf planning areas (Alaska). Source: MMS, 1987a.

FIGURE 1-2 Outer Continental Shelf planning areas (contiguous United States). Source: MMS, 1987a.

Suggested Citation:"1. Introduction." National Research Council. 1992. Assessment of the U.S. Outer Continental Shelf Environmental Studies Program: II. Ecology. Washington, DC: The National Academies Press. doi: 10.17226/1963.
×

Environmental Concerns

Offshore drilling has been conducted since the beginning of this century, mostly in shallow state waters. Until 1969, potential environmental damage was primarily a local concern in the affected states. Then, in January 1969, oil-spill damage resulting from a major blowout at a Union Oil platform in the Santa Barbara Channel brought environmental concerns to national attention (Congressional and Administrative News of the U.S. Code, 1978). That oil spill covered 1062 km2, including 241 km of coastline (Cicin-Sain, 1986).

The potential impacts of oil spills resulting from OCS development and production on resources, such as fisheries, and endangered species have caused environmental concern. Other sources of potential adverse impacts associated with OCS development include the discharge of produced water and drilling muds and the chronic loss of oil at drilling sites. Seismic surveys and the construction and operation of platforms and pipelines can disturb wildlife and interfere with commercial, recreational, and subsistence fishing activities, and potentially adverse socioeconomic impacts are associated with the construction of onshore support facilities (NRC, 1978; MMS, 1987b). The potential for long-term, chronic environmental effects is also a source of concern (Table 1-3 ; Boesch and Rabalais, 1987). The effects of oil spills and drilling-mud discharges have been the subject of previous National Research Council (NRC) reviews (NRC, 1975, 1983, 1985). Table 1-3 summarizes some of the major potential effects of OCS exploration and development activities but is not exhaustive. Other potential effects include pressure effects of some types of seismic surveys, disturbance of the seabed as a result of rig emplacement and platform installation, and noise at all post-lease phases of OCS activity —oil spills are also possible during the exploration stage and there are potential impacts in post-production activities such as the removal of platforms.

Oil discharged from OCS operations has been estimated to contribute approximately 1% of oil inputs in the world's oceans from all sources (NRC, 1985), but it is a major source of public concern. In 1970-1989, there were 1,784 spills of more than 1 bbl each from OCS leases in the Gulf of Mexico, of which 80 were over 50 bbl, for a total estimated spillage of over 176,000 bbl (Table 1-4). In the Pacific in the same years, there were 28 spills, all of 1-50 bbl each, for a total of 165 bbl. Natural seepage in the Pacific OCS for the period is estimated to have been more than 28,000 bbl. Total spillage and seepage for both regions in 1970-1989 thus was around 205,000 bbl (MMS, 1990a). In 1964-1989, there were 22 oil spills of more than 1,000 bbl each from OCS leases. An estimated total of 447,522 bbl was spilled. Table 1-5 provides the location and type of accident for those spills—all but one of which were in the Gulf of Mexico.

Oil also reaches the marine environment from natural sources (e.g., marine seeps and sediment erosion), transportation (including tanker operations, dry-docking, marine terminals, bilge and fuel oils, and tanker and nontanker accidents), atmospheric deposition, and municipal wastes (refineries, nonrefining industrial wastes, urban runoff, river runoff, and ocean dumping) (NRC, 1985).

Impacts to marine communities can occur during exploration, development, and production (Neff et al., 1987) as well as post-production activities. Potential impacts associated with each stage are distinct and require different suites of studies for prediction of their extent and duration. Exploration and production activities can result in the discharge of several classes of contaminants, including petroleum hydrocarbons (from drilling fluids, produced waters, and spillage) and trace metals (from drilling fluids and produced waters). The relative importance of each contaminant class depends on previous exploration and production activities and on the operational practices in a given area (Boehm, 1987).

During exploration, drilling results in the discharge of sediment, drill cuttings, and

Suggested Citation:"1. Introduction." National Research Council. 1992. Assessment of the U.S. Outer Continental Shelf Environmental Studies Program: II. Ecology. Washington, DC: The National Academies Press. doi: 10.17226/1963.
×

TABLE 1-3 Major Activities in the Development of an Offshore Oil and Gas Field and Their Potential Effects

Activities

Potential Effects

EVALUATION

 

Seismic surveying

Noise effects on fishes and mammals

EXPLORATION

 

Rig fabrication

Dredging and filling of coastal habitats (mostly overseas)

Rig emplacement

Seabed disturbance due to anchoring

Drilling

Discharge of drilling fluids and cuttings; risk of blowouts

Routine rig operations

Deck drainage and sanitary wastes

Rig servicing

Discharges from support vessels and coastal port development

DEVELOPMENT AND PRODUCTION

 

Platform fabrication

Land use conflicts and increased channelization in heavily developed areas

Platform installation

Coastal navigation channels; seabed disturbance resulting from placement and subsequent presence of platform

Drilling

Larger and more heavily concentrated discharges of drilling fluids and cuttings; risk of blowouts

Completion

Increased risk of oil spills

Platform servicing

Dredges and coastal port development; discharges from vessels

Separation of oil and gas from water

Chronic discharges of petroleum and other pollutants

Fabrication of storage facilities and pipelines

Coastal use conflicts

Offshore emplacement of storage and pipelines

Seabed disturbances; effects of structures

Transfer to tankers and barges

Increased risk of oil spills; acute and chronic inputs of petroleum

Construction of on-shore facilities for transportation and storage

Coastal use conflicts; alterations of wetlands in pipeline corridors

Pipeline operations

Oil spills; chronic leaks

REFINING

 

Construction and expansion

Coastal use conflicts

Operations

Increased pollutant loading; depends on regional demands, imports, etc.

Source: Neff et al., 1987.

drilling fluids to the seafloor (Neff et al., 1987), in addition to the disturbances of the environment caused by the placement of drilling platforms. Drilling fluids are recirculated to cool and lubricate the drill bit and are separated from drill cuttings on the drill rig. Fluids and

Suggested Citation:"1. Introduction." National Research Council. 1992. Assessment of the U.S. Outer Continental Shelf Environmental Studies Program: II. Ecology. Washington, DC: The National Academies Press. doi: 10.17226/1963.
×

TABLE 1-4 Crude Oil and Condensate Spills of 1 Bbl or More from Offshore Wells on Federal Leases, 1970-1989

 

Gulf of Mexico OCS

 

Pacific OCS

 
 

Number of Spills

 

Number of Spills

 

Year

1-50 Bbl

More than 50 Bbl

Total Spillage, Bbl

1-50 Bbl

More than 50 Bbl

Total, Spillage, Bbl

Grand Total, Spillage, Bbl

1970

8

5

83,894

0

0

0

83,894

1971

267

7

2,446

0

0

0

2,446

1972

203

1

997

0

0

0

997

1973

178

5

23,125

0

0

0

23,125

1974

80

7

24,453

0

0

0

24,453

1975

109

2

761

0

0

0

761

1976

66

4

5,103

1

0

2

5,105

1977

71

3

1,087

1

0

4

1,091

1978

79

3

1,528

0

0

0

1,528

1979

114

4

2,700

1

0

2

2,702

1980

50

9

2,922

1

0

5

2,927

1981

65

5

5,793

9

0

73

5,866

1982

70

3

1,155

1

0

3

1,177a

1983

91

9

2,528

2

0

4

2,556b

1984

59

1

378

3

0

36

416a

1985

66

5

1,611

1

0

5

1,618a

1986

40

2

356

2

0

11

367

1987

34

1

232

2

0

10

242

1988

29

3

15,280

1

0

2

15,287a

1989

25

1

479

3

0

8

487

TOTALS

1,704

80

176,828

28

0

165

177,045

NOTE: These figures do not include natural seepage. Natural seepage in the Santa Barbara Channel is estimated at 40-670 bbl/day (14,600-244,500 bbl/year) from more than 2,000 seeps.

a These totals include spills for the Alaska OCS: 1982, one spill, 19 bbl; 1984, one spill 2 bbl; 1985, one spill, 2 bbl; and 1988, one spill, 5 bbl.

b This total includes two spills totaling 24 bbl on the Atlantic OCS in 1983.

Source: MMS, 1990a.

cuttings are discharged separately (cuttings continuously and drilling fluids after reuse). Other discharges during exploration include water drainage from the deck of the rig that can contain drilling fluids, oil, and small amounts of industrial chemicals used on the rig; treated wastes; and discharges from support vessels. Exploratory drilling occurs for a relatively short duration and relatively little waste is discharged. If no economically viable resource is detected in a new area,

Suggested Citation:"1. Introduction." National Research Council. 1992. Assessment of the U.S. Outer Continental Shelf Environmental Studies Program: II. Ecology. Washington, DC: The National Academies Press. doi: 10.17226/1963.
×

TABLE 1-5 Crude Oil and Condensate Spills of 1,000 Bbl or More from Offshore Wells on Federal Leases, 1964-1989

Year

Location

Type of Accident

Number of Barrels Spilled

1964

Eugene Island

Freighter struck platform

2,559

1964

Eugene Island

Platform in hurricane

5,180

1964

Ship Shoal

Platform in hurricane

5,100

1964

Ship Shoal

Platform in hurricane

1,589

1965

Ship Shoal

Well blowout

1,688

1967

West Delta

Anchor damage to pipeline

160,638

1968

South Timbalier

Anchor damage to pipeline

6,000

1969

Santa Barbara Channel

Well blowout

77,000

1969

Main Pass

Anchor damage to pipeline

30,000

1969

Ship Shoal

Ship struck platform in storm

2,500

1970

Main Pass

Well blowout

30,000

1970

South Timbalier

Well blowout

53,000

1973

West Delta

Structural failure/tank rupture

9,935

1973

South Pelto

Storage barge sank

7,000

1973

West Delta

Pipeline corrosion

5,000

1974

Eugene Island

Anchor damage to pipeline

19,833

1974

Main Pass

Hurricane damage to pipeline

3,500

1976

Eugene Island

Shrimp trawl damage to pipeline

4,000

1979

Main Pass

Vessel collided with semisubmersible

1,500

1980

High Island

Pump failure, tank spill

1,456

1981

South Pass

Anchor damage to pipeline

5,100

1988

Galveston

Anchor damage to pipeline

14,944

TOTAL

 

447,522

Source: MMS, 1990a.

resource is detected in a new area, activity ceases after the drilling of one or more exploratory wells. If oil or gas reserves are found, the possibility of a “blowout” exists, but preventive measures render it unlikely.

The characteristics and volume of discharged materials during development and production (Table 1-6) differ from those during exploration, and materials are discharged over a longer period. During development and production there are: (1) greater density of wells, each with its own discharge requirements, (2) discharge of produced water or formation water, which contains lower-molecular-weight compounds—mainly hydrocarbons—and smaller amounts of medium- and higher-molecular-weight compounds, (3) increased risk of blowout, (4) greater risk of oil spills during transfer to tankers and barges or in pipeline operations, (5) chronic leakage of petroleum hydrocarbons from platform operations, and (6) potential for decrease in environmental awareness of operating crew with regard to executing and implementing

Suggested Citation:"1. Introduction." National Research Council. 1992. Assessment of the U.S. Outer Continental Shelf Environmental Studies Program: II. Ecology. Washington, DC: The National Academies Press. doi: 10.17226/1963.
×

TABLE 1-6 Major Permitted Discharges and Potential Impact-Causing Agents Associated with Offshore Oil and Gas Exploration and Production

Drill cuttings

1,100 MT/exploration well, less for development well

Drilling fluids

900 MT/exploration well, 25% less for development well

Cooling water, deck drainage, ballast water

May be treated in an oil/water separator

Domestic sewage

Primary activated sludge treatment

Sacrificial anodes, corrosion, antifouling paints

Might release small amounts of several metals (aluminum, copper, mercury, indium, tin, zinc)

Produced water (during production only)

Treated in oil/water separator to reduce total hydrocarbon to mean of 48 ppm, daily maximum of 72 ppm

Source: Neff et al., 1987.

environmental regulations governing the wide array of discharges. The fate of the discharges in the vicinity of a platform will depend heavily on processes at the site, and potential effects will depend on the characteristics of the biological communities involved.

The composition of produced waters varies considerably with the nature of the hydrocarbon reserves and geological formations (Collins, 1975; Jackson et al., 1981; Lysyj, 1982). Produced waters consist primarily of an oily brine brought to the surface with produced hydrocarbons (Boehm, 1987). The oil content is usually reduced by gravity separation before discharge, but various organic and inorganic constituents remain. Among the organic constituents are low-molecular-weight hydrocarbons, such as benzene and toluene (Middleditch, 1981; Sauer, 1981; Neff et al., 1987), that are highly water-soluble and can be accumulated by benthic organisms (Armstrong et al., 1979). Discharge of produced waters is regulated by the Environmental Protection Agency, particularly to restrict the concentration of oil and grease. Treatment of produced waters is designed to remove particulate or dispersed oil, but is ineffective in removing dissolved petroleum hydrocarbons, other organic chemicals, or trace metals (Neff et al., 1987).

Benthic systems can also be disturbed during exploration, development, and production, because of increasing turbidity and changes in grain-size distribution in the vicinity of the platform, anchoring rig, and platform structures; dredging for navigation channels and to provide materials (e.g., for causeways and platforms); and coastal port development. Modes of transportation from offshore platforms depend on the product (oil or gas), the amount of production, the distance to shore, the nature of the environment between the platform and the shore, and the capabilities of onshore facilities (Boesch et al., 1987). Thus, assessing the impacts of oil and gas exploration, development, and production requires a detailed understanding of coastal, continental shelf, and slope processes that govern the transport, fate, and effects of discharges from operational activities.

The major questions that must be addressed in an assessment of the impacts of oil and gas exploration, development, and production are the following:

  • What is the fate of discharged materials?

Suggested Citation:"1. Introduction." National Research Council. 1992. Assessment of the U.S. Outer Continental Shelf Environmental Studies Program: II. Ecology. Washington, DC: The National Academies Press. doi: 10.17226/1963.
×
  • What is the potential for large-scale changes in benthic, pelagic, and coastal communities as a result of OCS operational activities and what is their ecological significance?

  • What resources would be affected and what is the comparative sensitivity of different continental shelf habitats to OCS operational activities?

  • How predictable are the impacts of OCS operational activities?

  • Can the impacts be measured and their causes identified?

Addressing those questions requires both the characterization of OCS habitats through observational studies and innovative experimentation, to differentiate between natural variability and the effects of OCS operational activities. Processes that affect the fate and transport of trace contaminants are many and complex, because biological, chemical, and physical effects can all contribute to the ultimate distribution of contaminants. Determining the dominant processes requires a coherent, integrated field program that is focused on assessing not only the concentration, but also the rate of transport of a contaminant through an ecosystem. In reality, such a field program is exceedingly expensive and too narrow and brief to characterize contaminant transport and effects, particularly long-term effects, adequately. A suite of observation, experiment, and modeling is often required for timely and cost-effective predictive assessments.

THE ENVIRONMENTAL STUDIES PROGRAM

Mandate

Under the OCSLA as amended in 1978, MMS must manage the OCS oil and gas program with consideration for the economic, social, and environmental values of both renewable and nonrenewable resources; for the marine, coastal, and human environments that could be affected; for the laws, goals, and policies of affected states; and for the equitable sharing of developmental benefits and environmental risks among the various regions. Timing and location of leasing must be selected, to the greatest extent practicable, to balance the potential for environmental damage, the potential for discovery of oil and gas, and the potential for adverse impact on the coastal zone (43 U.S.C. §1344).

To balance the benefits of the leasing program with environmental concerns, MMS must conduct environmental studies. The OCSLA establishes two goals for the MMS Environmental Studies Program (ESP). The first goal is to develop information needed for “the assessment and management of environmental impacts on the human, marine, and coastal environments of the OCS and the coastal areas that may be affected by oil and gas development” in the proposed leasing area (43 U.S.C. §1346 (a)(1)). To the extent practicable, studies must be “designed to predict impacts on the marine biota, which may result from chronic low-level pollution or large spills associated with OCS production, from the introduction of drill cuttings and drilling muds in the area, and from the laying of pipe to serve the offshore production area, and the impacts of development offshore on the affected coastal areas” (43 U.S.C. §1346 (a)(3)).

The second goal is to conduct additional studies subsequent to the leasing and development of an area or region as the secretary deems necessary and to “monitor the human, marine, and coastal environments of such an area or region to provide time-series and data-trend information which can be used for comparison with previously collected data to identify important changes in the quality and productivity of such environments, to establish trends in

Suggested Citation:"1. Introduction." National Research Council. 1992. Assessment of the U.S. Outer Continental Shelf Environmental Studies Program: II. Ecology. Washington, DC: The National Academies Press. doi: 10.17226/1963.
×

the areas studied and monitored, and to design experiments to identify the causes of changes” (43 U.S.C. §1346 (b)).

The secretary must also each year “submit to the Congress and make available to the general public an assessment of the cumulative effect of activities conducted under this subchapter on the human, marine, and coastal environments” (43 U.S.C. §1346 (e)). Although the assessment should make use of information generated by the Branch of Environmental Studies (BES), the report is prepared by another branch of MMS. (The first such report, dated 1988, was released in 1990.) Under the same section, the secretary must establish procedures for the conduct of the required studies. The OCSLA (43 U.S.C. §1334 (a)(8)) requires the secretary to regulate OCS activities to ensure that they do not prevent the attainment of National Ambient Air Quality Standards.

The secretary must use information prepared as noted here to support leasing decisions, promulgate regulations, set lease terms, and establish operating procedures (Congressional and Administrative News of the U.S. Code, 1978; 43 U.S.C. §1346 (d)).

Environmental information is used to support permit decisions, in addition to lease-sale decisions. Separate permits are required before geological and geophysical surveys, exploration, development, and production can be conducted. Exploration, development, and production plans must be submitted to MMS with an environmental report and a certificate of consistency with state coastal zone management plans (under the Coastal Zone Management Act (CZMA) 16 U.S.C. §1451-1464) from each coastal state affected.

The environmental information is also used as the basis for ensuring compliance with other applicable environmental laws, such as the National Environmental Policy Act (NEPA) (42 U.S.C. §4321-4347). NEPA requires federal agencies to “utilize a systematic and interdisciplinary approach which will insure the integrated use of natural and social sciences and the environmental design arts in planning and in decision making which may have an impact on man's environment” and to prepare environmental impact statements before major federal actions. The Endangered Species Act (ESA) of 1973 (16 U.S.C. §1531-1543) requires MMS to consult with the Fish and Wildlife Service (FWS) and the National Marine Fisheries Service (NMFS) to ensure that OCS activities do not cause harm to endangered or threatened species or damage or destroy their habitats.

Specifically, Section 7 of the ESA (16 U.S.C. §7) requires all federal agencies, in consultation with the Secretary of the Interior or the Secretary of Commerce and to the extent practicable consistent with their primary mission, to use their authority to carry out programs to conserve endangered and threatened species and to ensure that agency actions are “not likely to jeopardize the continued existence of endangered or threatened species or result in the destruction or adverse modification of habitat of such species which is determined by the Secretary, after consultation with the appropriate affected states, to be critical, unless such agency has been granted an exemption. ” The act also requires that agencies use the “best scientific and commercial data available” to fulfill those requirements.

The secretary is required to provide a written opinion, based on consultation, as to whether and how a proposed agency action would be likely to jeopardize any endangered or threatened species, including a summary of the information on which the opinion is based. If the secretary concludes that an action would jeopardize a species in question or adversely modify its habitat, he or she must suggest reasonable and prudent alternatives that would not violate the ESA. Once the consultation process has been initiated, the agency proposing the action is prohibited from making “any irreversible or irretrievable commitment of resources [that] has the effect of foreclosing the formulation or implementation of any reasonable and prudent alternative measures” that would not conflict with endangered species preservation.

Suggested Citation:"1. Introduction." National Research Council. 1992. Assessment of the U.S. Outer Continental Shelf Environmental Studies Program: II. Ecology. Washington, DC: The National Academies Press. doi: 10.17226/1963.
×

The OCSLA requires that OCS activities be carried out in distinct phases—leasing, exploration, and development. The courts have held that, when there is insufficient information to determine whether a total action would be likely to jeopardize an endangered species, the secretary can conclude that intermediate activities (leasing and other pre-exploration activities) would not jeopardize a species. The courts did not consider leasing to be an irreversible or irretrievable commitment of resources, because the secretary has the authority to cancel a lease sale at any stage of the process, if there is evidence of jeopardy to an endangered species (North Slope Borough v. Andrus, 642 F.2d 589 (D.C. Cir. 1980); Conservation Law Foundation v. Andrus, 623 F.2d 712 (1st Cir. 1979); California v. Watt, 520 F. Supp. 1359, 1387 (C.D. Cal. 1981); Bean, 1983).

Other environmental laws applicable to OCS activities include the Federal Water Pollution Control Act Amendments of 1972 (33 U.S.C. §1251-1375, P.L. 92-500), the Alaska National Interest Lands Conservation Act (16 U.S.C. §3101-3233, P.L. 96-487), the National Historic Preservation Act (16 U.S.C. §470-470 w6, P.L. 89-665), and the Marine Protection, Research and Sanctuaries Act of 1972 (33 U.S.C. §1401-1445, P.L. 92-352).

History of the Environmental Studies Program

DOI established its ESP in 1973, in large part to comply with the requirements of NEPA. From its inception, when it was administered by BLM, through 1989, the ESP invested over $478 million in a wide variety of studies, or approximately 0.5% of the total cumulative federal offshore oil and gas revenue of $90 billion. Funding for the program has averaged $30 million per year, but has recently declined to approximately $20 million per year (MMS, 1987c). Most studies are performed by contractors to DOI (MMS, 1988a). In addition to its headquarters (in Washington, D.C. and Herndon, Va.), MMS has an office for each of four regions: Alaska, Pacific, Gulf of Mexico, and Atlantic. The four regional offices (in Anchorage; Camarillo, Calif.; New Orleans; and Herndon, Va.) are responsible for defining and contracting most of the studies.

From 1974 through 1977, baseline studies were conducted in each OCS region where industry expressed an interest in leasing. According to MMS, those were large-scale, multidisciplinary studies designed to provide decision-makers with statistically valid baselines of the geological, physical, biological, and chemical characteristics of the proposed leasing areas (MMS, 1987c). The baseline studies were intended to be used to evaluate the impact of OCS oil and gas operations. After an NRC review (NRC, 1978), MMS abandoned the baseline concept, because the studies were not providing timely and appropriate information for leasing decisions (MMS, 1987c). According to the NRC report, the baseline studies were not useful for management decisions, because they were descriptive and provided no basis for distinguishing natural variability from changes caused by OCS operations. NRC (1978) recommended that the ESP focus on the prediction of impacts of OCS operations and design specific cause-effect experiments to “establish the vulnerability of key species or communities.”

In 1975, the Secretary of the Interior established a national OCS Advisory Board to provide guidance and recommendations on the leasing and development process, to receive comments and recommendations from state officials and other interested parties, and to provide a forum for discussion among the federal agencies involved. The advisory board consists of a policy committee, a scientific committee (SC), and six regional technical working groups (RTWGs)—three for the Atlantic region and one for each of the other regions—to review political, scientific, and technical aspects of OCS development, and to balance federal, state, and

Suggested Citation:"1. Introduction." National Research Council. 1992. Assessment of the U.S. Outer Continental Shelf Environmental Studies Program: II. Ecology. Washington, DC: The National Academies Press. doi: 10.17226/1963.
×

local interests and public and private interests. The SC was established specifically to provide guidance for and to review the ESP. The RTWGs provide recommendations on the entire leasing and development process, including the ESP (MMS, 1988b) (see Fig. 1-3).

FIGURE 1-3 Outer Continental Shelf Advisory Board organizational chart. Source: MMS, 1987a.

As a result of the 1978 NRC review, the entire ESP was restructured in late 1978 with the goal of providing more immediately usable results for leasing and management decisions and a framework for establishing study priorities (MMS, 1987c). Under the mandate to establish procedures for environmental studies, guidance in the form of Study Design for Resource Management Decisions: OCS Oil and Gas Development and the Environment (BLM, 1978) was prepared by an ad hoc advisory committee; it was adopted by the OCS Advisory Board on April 29, 1978. The guidance document requires identification of management decisions and studies to provide information needed for them (BLM, 1978).

According to Don Aurand (1988), then Chief of the Branch of Environmental Studies, the goals of the ESP are to:

  • Provide information on the status of the environment that can be used to predict the impacts of OCS oil and gas development.

  • Provide information on how and to what extent OCS development can potentially affect the human, marine, biological, and coastal environments.

  • Ensure that information already available or being collected under the program is in a form that can be used in decision-making associated with a specific leasing action or with longer-term OCS minerals management responsibilities.

  • Provide a basis for future environmental monitoring of OCS operations, including assessments of short-term and long-term impacts attributable to the OCS oil and gas program.

Planned changes in the program designed to support the current lease schedule include a change of emphasis from prelease general studies to studies of postlease environmental affects,

Suggested Citation:"1. Introduction." National Research Council. 1992. Assessment of the U.S. Outer Continental Shelf Environmental Studies Program: II. Ecology. Washington, DC: The National Academies Press. doi: 10.17226/1963.
×

more emphasis on generic studies, and development of a strategy for postlease monitoring (Aurand, 1988; MMS, 1988b).

Development of a Studies Plan

In 1978, a framework was established for setting study priorities on the basis of their importance for decision-making, their timeliness, the generic applicability of their results, the availability of information, and their applicability to issues of regional or ESP concern. To develop a list of study topics, issues are identified by MMS—primarily in the regional offices and by advisory groups and interested parties. The issues are then translated into questions that reflect information needed for decision-making.

The MMS regional offices, with help from the RTWGs and the SC, evaluate the list of study topics for scientific and technical feasibility, information availability, scientific merit, and time required for gathering information. The list is also reviewed by other federal agencies and scientists in the academic community, in state and local governments, and in industry. When the review is finished, each regional office submits a draft of a regional plan for studies to MMS's Branch of Environmental Studies (BES, also referred to as Headquarters) in Herndon, Virginia. Each draft plan includes a statement of regional needs for information, the regional perspective on the priorities of these needs, a list of proposed study topics, and a brief description of the rationale for each proposed study. The BES coordinates the development of a “national studies list” from the proposed study topics and ranks them for funding priority according to a set of criteria. Those criteria, developed jointly by DOI and the Office of Management and Budget (OMB) (GAO, 1988), give priority to studies required to fulfill legislative mandates and other legal requirements and studies that will be completed in time for use in specific leasing decisions. Studies are then funded by MMS from its appropriated budget according to rank, until funds are exhausted. Since 1982, MMS has been providing support for the review, publication, and dissemination of ESP results, including publication in refereed journals (DOI, MMS, pers. commun., 1990).

In Alaska, marine environmental studies have been administered in part by the National Oceanic and Atmospheric Administration (NOAA) as part of the OCS Environmental Assessment Program (OCSEAP), under an interagency agreement with MMS that is renewed every 5 years. When a national studies list is approved, NOAA prepares a technical development plan for studies in the Alaska region (NMFS, 1988a). In FY 1974 through FY 1988, $181.7 million was allocated to OCSEAP for environmental studies, of a total of $228.4 million allocated for the Alaska region ESP (GAO, 1988).

In June 1988, the General Accounting Office (GAO) issued a report that concluded that, because of reductions in funding, the duplication of administrative functions between NOAA and MMS had become less efficient and that consolidation of the programs could save up to $1.3 million a year. GAO recommended that MMS develop alternatives to make its program more efficient and, in the selection of alternatives, consider other issues—such as staffing, public perception of objectivity, and continuity of scientific expertise—in addition to potential dollar savings (GAO, 1988). MMS and NOAA have been working to reduce management duplication by attempting to use NOAA staff for scientific investigation, rather than as technical managers of contracted studies. In practice, it has been difficult to match NOAA/OCSEAP staff skills with MMS needs. However, in response to the GAO recommendation, MMS intends to negotiate an agreement that NOAA will cease to issue contracts by the beginning of the next 5-year agreement in FY 1991 and thereafter propose only inhouse studies. MMS would agree to

Suggested Citation:"1. Introduction." National Research Council. 1992. Assessment of the U.S. Outer Continental Shelf Environmental Studies Program: II. Ecology. Washington, DC: The National Academies Press. doi: 10.17226/1963.
×

support the previously agreed-on 5-year work plan (MMS, 1988c). [MMS has informed the panel that in 1991, the agreement ended and MMS has assumed responsibility for former NOAA/OCSEAP activities.]

Implementation of Studies According to Lease-Sale Schedules

The planning process for individual studies has been governed primarily by a lease-sale schedule, which is established in a 5-year planning document. The most recent 5-year program plan is for the period between mid-1987 and mid-December 1992. Most studies must be initiated well in advance of a lease sale or any other decision they are intended to support, if they are to be useful. A prelease 15-month study would normally be included in a regional studies plan approximately 34 months before the beginning of the lease-sale process, which begins with the identification of areas that have hydrocarbon potential. Table 1-7 provides an example of how a prelease study is tied to the planning and implementation steps in the ESP and in the OCS leasing process (MMS, pers. commun., 1988). The actual timing varies with the individual studies and lease sales.

MMS Support of Ecological Studies

From 1973 to 1989, total MMS funding of ecological studies in all regions amounted to $259,658,776. That figure was derived from the MMS environmental studies contracts database by adding the cumulative amounts of funding for studies coded as being related to the topics of biology, endangered species, fates and effects, and baseline studies. A breakdown of the amounts spent on each topic by region is provided in Table 1-8.

THE PRESENT STUDY AND REPORT

In 1986, in response to a request from MMS, the National Research Council's Board on Environmental Studies and Toxicology formed the Committee to Review the Outer Continental Shelf Environmental Studies Program. The committee consists of experts in ecology, energy production, geochemistry, marine geophysics, oil-field technology, geology, law, physical and biological oceanography, policy, and resource management. It is reviewing the adequacy and appropriateness of the studies that are used to support leasing decisions and to predict and manage environmental impacts of OCS activities. The committee's report will include a review of the literature of selected fields and recommendations for directions for the program to follow.

The committee recognized during its deliberations that there are several ways to divide the issues addressed by the ESP and the content of the ESP studies—e.g., into regional, disciplinary (including subdisciplinary), and generic problems. The committee has established three panels to provide reviews of disciplines that make up the ESP. Those panels are focusing on physical oceanography, ecology, and socioeconomics. Between-panel issues and overarching issues for the ESP will be addressed in the report that the committee prepares after it receives and reviews the panel reports. The present report—the second of three panel reports —focuses on ecological aspects of the ESP.

The Ecology Panel recognizes that the ESP is not intended to be a broad, general science program like that of the National Science Foundation. Rather, it is a mission-oriented program, designed to answer questions about the environmental and socioeconomic effects of oil

Suggested Citation:"1. Introduction." National Research Council. 1992. Assessment of the U.S. Outer Continental Shelf Environmental Studies Program: II. Ecology. Washington, DC: The National Academies Press. doi: 10.17226/1963.
×

TABLE 1-7 Planning and Implementation Steps in the OCS Environmental Studies Program and Lease-Sale Process

Month

Step

−34

Draft regional study plan

−30

Final regional study plan

−27

National studies plan

−20

Procurement plan

−17

Draft statement of work

−12

Final statement of work

− 7

Request for proposal

− 3

Contract

0

Area of hydrocarbon potential identified

1

Call for information: MMS publishes notice of intent to prepare EIS in Federal Register; industry invited to indicate interest; interested parties may comment on topics and areas of concern; no decision yet made about proceeding with sale

5-9

Identification of area to be analyzed in EIS, identification of alternatives for EIS, estimation of resources, and preparation of oil spill report for proposed action and for alternatives; draft report of study results due

12

Draft EIS and final report of study results—describes planning area, analyzes potential environmental effects of oil and gas leasing, and discusses mitigating measures proposed to resolve conflicts; followed by public-comment period

13

Public hearing—opportunity for oral comments on draft EIS

14

Close of period for comment on draft EIS

18

Final EIS—assesses comments from state(s) and public; secretarial issue document (SID) prepared that analyzes all issues involved in proposed sale and possible coastal zone consistency conflicts; SID, accompanied by EIS, is sent to assistant secretary for review and decision on whether to issue proposed notice of sale

19

Proposed notice of sale—details terms and conditions of proposed sale, blocks proposed for leasing, stipulations and other mitigating measures to be required, and proposed bidding systems

21

Governor's comments due—used by MMS to develop recommendations to secretary; SID and final EIS sent to secretary; secretary is required to accept recommendations of governor if he or she determines that they provide reasonable balance between national interest and interests of state(s)

22

Final notice of sale—published at least 30 days before sale; specifies date, time, location, blocks to be offered, and terms and conditions of sale

23

Sale—sealed bids opened and read by regional director

24

Bid review—high bids evaluated to ensure receipt of fair-market value; sale results also reviewed by Department of Justice to ensure that awarding leases does not violate antitrust laws

25

Leases issued—bids accepted or rejected within 90 days of receipt; leases issued for accepted bids 1-2 months after sale

NOTES: In this example, 5 years elapse from the completion of a draft regional studies plan to the lease sale. The postlease process includes (1) exploration-plan evaluation and drilling-permit approval, (2) development- and production-plan evaluation and approval, (3) pipeline-permit issuance, and (4) lease termination or expiration. Source: MMS, pers. commun., 1988.

Suggested Citation:"1. Introduction." National Research Council. 1992. Assessment of the U.S. Outer Continental Shelf Environmental Studies Program: II. Ecology. Washington, DC: The National Academies Press. doi: 10.17226/1963.
×

TABLE 1-8 Expenditures for Ecological Studies by Study Topic and Region, FY 1973-1989

OCS Region

All Ecological Studies

Biology

Endangered Species

Fates and Effects

Baseline

Alaska

115,167,407

63,552,741

27,933,914

21,116,516

2,564,236

Atlantic

40,844,025

13,899,281

7,263,556

5,820,469

13,860,719

Gulf of Mexico

52,896,945

24,633,870

1,909,176

5,211,305

21,142,594

Pacific

44,496,186

22,559,879

4,346,051

4,587,302

13,002,954

Washington

6,254,213

2,514,294

219,747

2,243,579

1,276,593

TOTALS

259,658,776

127,160,065

41,672,444

38,979,171

51,847,096

Source: Compiled by the Ecology Panel from information provided byMMS.

and gas exploration and production. Nonetheless, the answers to those questions need to have a basis in sound science.

The panel based its report on several sources, including presentations from ESP staff; briefings by other, independent scientists familiar with the work supported by the ESP; results of a workshop on ecological studies held by the panel; and a review of relevant scientific literature and documentation of MMS's planning and implementation process leading to various lease sales. While this report was being prepared, the OCS committee and its panels interrupted their work to prepare two reports on the adequacy of environmental information for OCS decisions in response to government requests. The first, requested by President Bush, dealt with a lease sale off Florida and two off California (NRC, 1989a). The second, requested by MMS, focused on a north Atlantic lease sale (NRC, 1991).

For this report, the panel reviewed documents that were available through 1990. MMS has informed the panel that the ESP continues to evolve, and recent requests for proposals confirm that. MMS officials have also indicated that they are taking into account recommendations in the two recent reports mentioned above.

The Ecology Panel divided into three working groups to address the main issues of ecological concern in OCS development: marine birds, mammals, turtles, and endangered species, benthic processes, and fisheries and ecosystems. Because different ecosystem components require differences in study design, the sections of this report that deal with the different ecosystem components are not exactly parallel in form or equal in length. Studies addressing those issues were identified by keywords in the environmental studies database and by MMS. Table 1-9 provides a breakdown of funding for these types of studies by region (see Appendix B). The biological characteristics of different components of marine ecosystems dictate the type of information gathered for evaluation. Birds are relatively easy to observe, and their identification is straightforward. Few species in the OCS are endangered (some species in nearshore and shoreline habitats are endangered). Many aspects of avian marine ecology are difficult to study experimentally so most studies have been observational. The ESP analyses of birds have focused on the distribution and abundance patterns of species and provide an improved basis for assessment of immediate impact of OCS activities.

Marine mammals (and turtles) are equally identifiable. Many are uncommon or endangered, however, and most are difficult to observe or count. A significant ESP effort has been directed at sea otters and bowhead whales; in some instances, new technologies had to be

Suggested Citation:"1. Introduction." National Research Council. 1992. Assessment of the U.S. Outer Continental Shelf Environmental Studies Program: II. Ecology. Washington, DC: The National Academies Press. doi: 10.17226/1963.
×

developed for assessment. Except for studies of sea otters, little information was obtained on the dynamics or ecological (interactive) role of these species in community organization although there is at least one such study in progress.

Many fish species in the OCS are commercially important and are studied and managed by international commissions. Population data on many species have been gathered for decades, but recruitment mechanisms remain poorly understood. Thus, many assessments reflect stock distribution data and not trophic interactions or recruitment dynamics.

Finally, studies of OCS benthic environments are generally based on assemblages of organisms and contain minimal detail on the component species. Many species are undescribed taxonomically, none is on the Endangered Species List, some are economically valuable, and many provide excellent material for experimentation, either in the laboratory or in the field. Thus, assessments of benthic environments tend to describe the distribution and composition of assemblages or, at the other extreme, to identify chronic, sublethal influences on individual species.

The biological characteristics of the components of marine ecosystems dictated the types of information gathered for evaluation by the ESP and therefore the nature of the panel's review. OCS activities can have ecological effects during exploration, development, production, and decommissioning. The potential effects during each phase are distinct and require a different suite of studies for prediction of their extent and duration. The panel identified six objectives that it considers to be important for obtaining information for assessing and monitoring the environmental impacts of OCS oil and gas activities:

  • Characterization of major habitat types.

  • Cataloging of representative species (or major species groups) in the area of interest.

  • Description of seasonal patterns (including natural variation) of distribution and abundance of representative species (e.g., identification of spawning and feeding grounds).

  • Acquisition of basic ecological information on key or representative species (e.g., trophic relationships, habitat requirements, and reproduction).

  • Determination of basic information on factors that determine the likelihood that various populations and communities would be affected by OCS activities, and the potential for recovery.

TABLE 1-9 Funding Levels for Ecological Studies by Selected Topics and by Region, 1973-1989

OCS Region

Benthic

Fisheries

Birds

Marine Mammals

Alaska

22,840,616

38,399,493

16,009,980

36,312,817

Atlantic

35,765,484

20,033,934

666,004

6,723,340

Gulf of Mexico

43,796,487

12,060,782

1,530,543

1,354,138

Pacific

24,794,427

2,182,739

9,658,635

9,067,222

Washington

1,694,315

567,714

201,824

216,631

TOTALS

128,891,329

73,244,662

28,066,986

53,674,148

NOTE: This table does not include all ecological studies but only topics selected by the panel. Because of this, and because some studies cover several topics, the total amount does not match the total amount in Table 1-8. Source: Compiled by the Ecology Panel from information provided by MMS.

Suggested Citation:"1. Introduction." National Research Council. 1992. Assessment of the U.S. Outer Continental Shelf Environmental Studies Program: II. Ecology. Washington, DC: The National Academies Press. doi: 10.17226/1963.
×
  • Determination of potential effects of various agents of impact (e.g., spilled oil, operation discharges, noise, and other disturbances).

Information for the first three objectives is needed before leasing. More site-specific information is needed after leasing (during exploration, development, and production) so that activities may be stopped or modified before they reach unacceptable levels. All six objectives were kept in mind in the review of various components of the ESP and the preparation of recommendations for future studies.

Suggested Citation:"1. Introduction." National Research Council. 1992. Assessment of the U.S. Outer Continental Shelf Environmental Studies Program: II. Ecology. Washington, DC: The National Academies Press. doi: 10.17226/1963.
×
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Suggested Citation:"1. Introduction." National Research Council. 1992. Assessment of the U.S. Outer Continental Shelf Environmental Studies Program: II. Ecology. Washington, DC: The National Academies Press. doi: 10.17226/1963.
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Suggested Citation:"1. Introduction." National Research Council. 1992. Assessment of the U.S. Outer Continental Shelf Environmental Studies Program: II. Ecology. Washington, DC: The National Academies Press. doi: 10.17226/1963.
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Suggested Citation:"1. Introduction." National Research Council. 1992. Assessment of the U.S. Outer Continental Shelf Environmental Studies Program: II. Ecology. Washington, DC: The National Academies Press. doi: 10.17226/1963.
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Suggested Citation:"1. Introduction." National Research Council. 1992. Assessment of the U.S. Outer Continental Shelf Environmental Studies Program: II. Ecology. Washington, DC: The National Academies Press. doi: 10.17226/1963.
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Suggested Citation:"1. Introduction." National Research Council. 1992. Assessment of the U.S. Outer Continental Shelf Environmental Studies Program: II. Ecology. Washington, DC: The National Academies Press. doi: 10.17226/1963.
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Suggested Citation:"1. Introduction." National Research Council. 1992. Assessment of the U.S. Outer Continental Shelf Environmental Studies Program: II. Ecology. Washington, DC: The National Academies Press. doi: 10.17226/1963.
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Suggested Citation:"1. Introduction." National Research Council. 1992. Assessment of the U.S. Outer Continental Shelf Environmental Studies Program: II. Ecology. Washington, DC: The National Academies Press. doi: 10.17226/1963.
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Suggested Citation:"1. Introduction." National Research Council. 1992. Assessment of the U.S. Outer Continental Shelf Environmental Studies Program: II. Ecology. Washington, DC: The National Academies Press. doi: 10.17226/1963.
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Suggested Citation:"1. Introduction." National Research Council. 1992. Assessment of the U.S. Outer Continental Shelf Environmental Studies Program: II. Ecology. Washington, DC: The National Academies Press. doi: 10.17226/1963.
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Suggested Citation:"1. Introduction." National Research Council. 1992. Assessment of the U.S. Outer Continental Shelf Environmental Studies Program: II. Ecology. Washington, DC: The National Academies Press. doi: 10.17226/1963.
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Suggested Citation:"1. Introduction." National Research Council. 1992. Assessment of the U.S. Outer Continental Shelf Environmental Studies Program: II. Ecology. Washington, DC: The National Academies Press. doi: 10.17226/1963.
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Suggested Citation:"1. Introduction." National Research Council. 1992. Assessment of the U.S. Outer Continental Shelf Environmental Studies Program: II. Ecology. Washington, DC: The National Academies Press. doi: 10.17226/1963.
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Suggested Citation:"1. Introduction." National Research Council. 1992. Assessment of the U.S. Outer Continental Shelf Environmental Studies Program: II. Ecology. Washington, DC: The National Academies Press. doi: 10.17226/1963.
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Suggested Citation:"1. Introduction." National Research Council. 1992. Assessment of the U.S. Outer Continental Shelf Environmental Studies Program: II. Ecology. Washington, DC: The National Academies Press. doi: 10.17226/1963.
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Suggested Citation:"1. Introduction." National Research Council. 1992. Assessment of the U.S. Outer Continental Shelf Environmental Studies Program: II. Ecology. Washington, DC: The National Academies Press. doi: 10.17226/1963.
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Suggested Citation:"1. Introduction." National Research Council. 1992. Assessment of the U.S. Outer Continental Shelf Environmental Studies Program: II. Ecology. Washington, DC: The National Academies Press. doi: 10.17226/1963.
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Assessment of the U.S. Outer Continental Shelf Environmental Studies Program reviews the ecological studies done by the Environmental Studies Program of the Minerals Management Service.

This program, which has spent $10 million a year on ecological studies in recent years, is designed to provide information to predict and manage the environmental effects of outer continental shelf oil and gas activities. The book considers studies on marine mammals and endangered species, birds, benthic organisms, fisheries, and marine ecosystems and makes recommendations for future studies.

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