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1 SEABED JURISDICTION AND UTILIZATION The Presidential proclamation of 1983 on the Exclusive Economic Zone (EEZ) brought to the nation's attention the enormous potential of the waters and seabed surrounding the United States. The primary goal of this study is to assess the state of knowledge of the seabed as it relates to future activities within the EEZ and to stimulate efforts aimed at the efficient and environmentally sound use of this vast area. ESTABLISHMENT OF THE EEZ Almost since this country was founded, the federal government has asserted control over its contiguous ocean regimes. Thomas Jefferson laid claim to a three-mile territorial sea in 1793, the Truman Proclamation of 1945 asserted jurisdiction over the natural resources of the continental shelf, the Outer Continental Shelf Lands Act (OCSLA) of 1953 established regulations for developing OCS mineral resources, and the Magnuson Fisheries Conservation and Management Act of 1976 (MFCMAN claimed ~ '()() mile. fi~h~.ri~.c r~ncPrvatinn cone . ~ _ _ _ ~ ~ _ __ ~ CAM ~ ^^ _^ ^_V ~ ^&V_^ ~ ~ ~ 8& TV &~- In 1983, President Reagan signed a proclamation confirming U.S. sovereign rights and control over all living and nonliving resources within 200 nautical miles of the U.S. coast in an Exclusive Economic Zone. This proclamation focused national attention on the resource potential of the vast waters and seabed surrounding the United States and its island territories, and set the stage for expansion of resource identification and recovery and other uses of this area. AREAL DEFINITION The area encompassed by the EEZ brings within the national domain 3.9 billion acres of submarine land-approximately 1.7 times the 2.3 billion acres of onshore U.S. territory (Figure 1-1~. By any measure, it is huge: it is also largely unexplored, poorly understood, and contains many diverse and fragile environments. The EEZ territory extends from the edge of the territorial sea, at 3 nautical miles (nmi. to a distance of 200 rim seaward of the coastal baseline (Figure 1-2~. ~. ~. ~. . . ~ ~ ~ Although the territorial sea was extended lo 1;z miles In SHYLY, no state boundary has been increased to this distance (Booda, 1989~. Thus, seabed uses discussed in this study are those operations and uses that occur beyond the territorial 3-mile limit. Coastal areas within 3 miles, where human activities associated with the marine environment are concentrated-including bays, estuaries, and rivers-are excluded. The seabed, the specific portion of the EEZ addressed by this study, includes the zone directly above the sediment-water interface (order of 1 to 10 m), where important physical, chemical, and biological gradients associated with the bottom occur, and the sediment strata to the depth of 1

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2 1 20E i, 40,~ <~~~.r' Northern As, Mariana / ~ Islands Do Howland and Baker Islands by ~ 10S ~o5~' (\ lo\ 1 20E 1 50E 50W _ _~40 JO no :on Island Fagatele Bay NMS ~ j~ American C7 `` J f \. Palmyra Atoll/ ~30 `~ USS Monitor NMS )' Gray Reef NMS Key Largo NMS . ~ / Puerto Rico/ \ ,,,~o Loos Ken \ ~ 10N 0 2000 Km 1 , 1 0 1000 N.M. 1 1 1 ~~ 10S \ ~\ 1 1 1 1 1 1 1 1, I I I \1 1 / 180 1 50W 120 90 60 FIGURE 1-1 The Exclusive Economic Zone of the United States and its trust territories. SOURCE: McGregor and Lockwood, 1985, p. 2 Exclusive Economic Zone 197 miles l FIGURE 1-2 The EEZ extends from the limit of the territorial sea (3 nautical miles [nm]) to 200 rim from the baseline. This idealized cross section of the continental margin shows the major physiographic provinces (shelf, slope, rise). The actual inclination of the continental slope is typically about 4 to 6; however, the slope is usually incised by canyons and channels with steeper local slopes. SOURCE: After McGregor and Lockwood, 1985.

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3 potential use (meters to hundreds of meters). The character of deeper sediment or crustal features, such as oil-bearing strata, are not directly considered in this report. As indicated in Figure 1-2 and explained in greater detail in Chapter 2, seabed regimes within the U.S. EEZ include virtually all types of ocean seabed features and processes. From these two definitions of the EEZ and the seabed, the diversity and complexity of the EEZ seabed regime can be appreciated. Its range includes relatively shallow water on the continental shelf where the seabed is affected by currents and wave action, sloping areas with steep submarine canyons rivalling the Grand Canyon where massive submarine landslides are potential hazards, areas continually reshaped by currents and ~benthic storms near the deep seafloor, and high latitude areas where ice processes dominate. These varied characteristics and the remoteness of the seabed make a complex and challenging environment for people to work in. Indeed, the inherent remoteness of the EEZ seabed and difficulty in making direct observations are the principal differences between working on "dry" land and in the ocean. It is only within the last 20 to 30 years, and especially the last 10 years, that an appreciation of the complexities of the seabed in these frontier areas has begun to emerge. Most of what is known about the shape of the seabed, including the configuration of the deeper strata, comes from remotely acquired acoustic data. Detailed information about the properties of the sediments comes from widely spaced sampling sites. In addition to the difficulties of observing and sampling the seabed, it is also extremely difficult to monitor the behavior of the sediments over a long period of time. RESOURCE UTILIZATION Over the last four decades, human activity in what is now known as the EEZ has increased substantially. Uses of the seabed that will be discussed in this report fall into three broad categories (summarized in Table 1-1~: 1. extractive uses-activities involving removal of resources from the environment; intrusive uses-those that disrupt the seabed or may degrade the environment; and benign uses-activities that take up space but do not impact the seabed or environment. In the extractive category, the two most significant resource recovery activities are extraction of oil and gas, and benthic fisheries. The offshore oil and gas industry has advanced to a high level of TABLE 1-1 Summary of Seabed Uses in the EEZ Extractive uses Intrusive uses Benign uses Oil and gas Pipelines, vessels Instrument deployment Living resources (potential spills) security systems, Minerals Waste disposal navigation, research, Energy systems (dredged material, monitoring sewage, industrial Sanctuaries, waste) archaeology Acoustics (active) Recreation Dumping (munitions, Habitats municipal waste), scuttling

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4 technical sophistication, and hydrocarbons can now be recovered in even the Frontiers areas of deeper water (over 300 m) and the Arctic. A flurry of interest in seafloor mining was generated by rapid advances in ocean technology during and after World War II, the post-war economic boom, and discovery of seabed minerals (especially the nodules and crusts rich in cobalt, manganese, nickel, and copper found in some areas of the seafloor). However, with a few notable exceptions, such as sand and gravel mining, and recent gold mining off Alaska, the offshore mining industry remains undeveloped, though recovery of seabed minerals is considered likely to become economically feasible in the future. A significant intrusive use of the seafloor is as a base for pipelines and cables. Oil and gas operations need pipelines to transport the raw material (or, in some cases, power from offshore terminals) to shore, and designing, constructing, and siting them in potentially unstable areas pose challenging engineering problems. Another increasing use of the seafloor is for communications and power transmission cables-both for commercial uses and military and national security applications. Except in shallow shelf waters where they can be buried, cables generally rest on top of the seafloor, where they are vulnerable to disruption by activities such as trawling for bottom fish, and by natural processes, such as erosion or slumping. There has been some dumping of sewage sludge and hazardous wastes in offshore waters beyond the territorial sea, but legislation has been proposed to substantially curtail these activities. However, it is likely that future pressures will force consideration of certain ocean regimes for disposal of selected waste products. Various proposals for disposal of industrial and radioactive wastes may be revived in the future, and technological developments could make the concept of burial in subseabed sediments a viable alternative to land-based disposal. Considering the accidents and improper practices that have resulted in environmental disasters in the past, the challenge of utilizing this expanded area becomes one of how to balance using its resources with ensuring its protection. Oil spills resulting from tanker accidents, offshore oil well blow-outs, and medical wastes washing ashore have provided graphic examples of the kind of harm that can result from human activities in the ocean. Fortunately, the negative impacts have been mostly localized, contained, or caused minimal long-term damage. The opportunity still exists to establish environmentally sound procedures for extracting living and nonliving resources; for using the seafloor and substrate for communication cables, pipelines, and waste disposal; for conducting research; and for preserving critical habitats and recreational and cultural areas. Expanded utilization of the EEZ in general, and the seabed in particular, will present technological problems, management issues, and environmental concerns. For example, much of the future development will depend on tools to survey, map, probe, sample, and monitor the seabed. Improved survey and mapping techniques will enhance the ability to identify seabed processes. Sampling, measurement, and monitoring technology will be necessary to obtain the detailed information required for quantified analyses of seabed processes. Improved technology will also be needed for most actual uses~hether to mine and process minerals, bury cables and pipelines, or dispose of waste. In the face of increasing pressures to use the EEZ seabed for activities like these and for other presently unforeseen uses, conflicts are inevitable. Their resolution will involve accommodating multiple uses or establishing priorities in the national interest. The original intent of this study was to assess engineering aspects of major uses of the seabed. However, early in its deliberations the committee determined that seabed use involves other issues as well. The study's outlook was therefore expanded to examine both technological and nontechnological issues surrounding all potential uses. The U.S. EEZ is a precious national resource of unprecedented dimensions, and actions taken to develop its resources over the coming decades will have important economic implications for future generations and could have long-range ecological effects.