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11 Ma for Effects and Their Accumulation The Committee on Cumulative Environmental Effects of Oil and Gas Activities on Alaska's North Slope was charged with reviewing information about oil and gas activi- ties on Alaska's North Slope with the objective of assessing their known and probable cumulative effects of those activi- ties on the physical, biotic, and human environments of the North Slope and the adjacent marine environment. The com- mittee also was directed to assess future cumulative effects, based on its judgment of likely changes in technology and the environment. The committee attempted to be thorough in its analyses to reduce the likelihood that important effects- and how they might accumulate would be undetected. The results of the committee's investigations are detailed in Chapters 6 through 9. The importance of effects is perceived differently by different individuals or groups. The committee is not aware of a satisfactory way of attributing some absolute degree of importance to effects, and so it attempted to describe the basis on which it assessed importance of the effects. For ex- ample, it considered ecological consequences, importance given by North Slope residents, irreversibility, degree of controversy, and economic consequences for North Slope residents. As described in Chapter 10, there was considerable dif- ficulty with assembling information for some analyses, both because of gaps in data and because of the inaccessibility of some information. Nevertheless, the committee did identify important effects of industrial activities on the North Slope and how they accumulate. Details that support its judgments are provided earlier in the report. The committee based its projections of future accumula- tion of effects on a 50-year scenario that assumes political stability and world prices for petroleum products that support the continued expansion of oil and gas activities westward across the Arctic Coastal Plain and southward into the foot- hills of the Brooks Range (Chapter 5~. Some effects are not 155 yet manifest; they will accumulate as consequences of past and current activity. They would occur even if North Slope oil and gas exploration and production ended today. Other effects will accumulate as a result of new activities. Mostly, they will involve increases of current effects, but new effects are likely to be created as well both by the expansion and by the ulti- mate retraction of industrial activity. Assessments of future effects are problematic because of the connection between world politics and the oil market. It is possible to guess, but no one knows for certain how the events of the next decade will affect oil prices or availability. Moreover, future industrial activities will be carried out in a physical climate that will change in ways that are difficult to predict. Nevertheless, if oil activity expands and a gas pipe- line is built, the continuing accumulation of effects is virtu- ally certain. Many laws and regulations affect oil and gas explora- tion, development, production, and transportation, and many federal, state, and local government offices are involved (see Appendix I). Regulatory oversight can be critical in reduc- ing the accumulation of undesirable effects. The committee's predictions of future effects and their accumulation assume that regulatory oversight will continue at least to the extent of the recent past. All of the effects identified by the committee accumu- lated as the result of the actual spread of industrial activity on the North Slope or as responses to the news that such activity was likely to occur. Since the 1960s, industrial activity on the North Slope has grown from a single operational oil field at Prudhoe Bay to an industrial complex that stretches from the Alpine field near the mouth of the Colville River on the west to the Badami oil field, about 39 km (23 mi) from the borders of the Arctic National Wildlife Refuge in the east. In 2001, oil development on the North Slope consisted of 19 producing fields connected to the rest of Alaska by a highway and a

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156 pipeline that cross the state. The network consists of 115 gravel drill sites, 20 pads with processing facilities, l 15 pads with other support facilities, 91 exploration sites, 13 offshore exploration islands, 4 offshore production islands, 16 air- strips, 4 exploration airstrips, 1,395 culverts, 960 km (596 mi) of roads and permanent trails, 450 mi (725 km) of pipe- line corridors, and 219 mi (353 km) of transmission lines. Gravel roads and pads cover more than 3,500 ha (8,800 acres), not including the Trans-Alaska Pipeline and the Dalton Highway, and gravel mines have affected nearly 2,600 ha (6,400 acres). Ubiquitous permafrost requires that this infrastructure not thaw its own foundations, imposing an architecture with environmental consequences of it own. Massive gravel fills under roads and other work surfaces are required to raise them 1.8 m (6 ft) above the tundra. Heated buildings and pipeline networks must be elevated on pilings, and the closely spaced oil wells are extensively refrigerated. This network has grown incrementally as new fields have been explored and brought into production (Chapter 4~. For a variety of reasons, nearly all roads, pads, pipelines, and other infrastructure whether in current use or not are still in place and are likely to remain into the future. Their effects are manifest not only at the physical footprint itself but also at distances that vary according to the environmental com- ponent affected. Effects on hydrology, vegetation, and ani- mal populations occur at distances up to several kilometers, and cumulative effects on wildland values especially vi- sual ones extend much farther, as can the effects on marine mammals of sound generated by some offshore activities. All effects attributable to the structures and the activities associated with them accumulate, and many will persist as long as the structures remain, even if industrial activity ceases. SOCIAL CHANGES IN NORTH SLOPE COMMUNITIES Without the discovery and development of North Slope petroleum, the North Slope Borough, the Alaska Native Claims Settlement Act, and hence the Arctic Slope Regional Corporation, either would not exist or would bear little resem- blance to their current form. Petroleum development has re- sulted in major, significant, and probably irrervisible changes to the way of life on the North Slope (Chapter 9~. The primary vehicle of change is revenue that has flowed into communities from property taxes levied by the North Slope Borough on the petroleum industry's infrastructure. Many North Slope resi- dents view many of these changes positively. However, social and cultural changes of this magnitude inevitably have been accompanied by social and individual pathology. Those ef- fects accumulate because they arise from several causes, and they interact. As adaptation occurs, the communities and the people who make them up interact in new and different ways with the causes of social change. CUMULATIVE EFFECTS OF ALASKA NORTH SLOPE OIL AND GAS Interference With Subsistence Activities Offshore exploration and development and the an- nouncement of offshore sales have resulted in perceived risks to Inupiaq culture that are widespread, intense, and themselves constitute a cumulative effect (Chapter 9~. The people of the North Slope have a centuries-old nutritional and cultural relationship with the bowhead whale and cari- bou. Most view offshore industrial activity both the ob- served effects and the threat of a major oil spill as threat- ening the bowhead population and, thereby, their cultural survival. Noise from exploratory drilling and marine seis- mic exploration has caused fall-migrating bowheads to avoid noise above 117-135 dB. The distances over which the migratory pathways of the whales have changed are not yet known, but the deflections forced subsistence hunters to travel greater distances than formerly to encounter whales. The results are increased risk of exposure to the dangers of the open sea and the increased likelihood that whale tissues will deteriorate before carcasses are landed and butchered. Recently the Alaska Eskimo Whaling Com- mission has reached agreements that restrict seismic-vessel operations during the fall hunting period, but they are rene- gotiated annually. The threat of a major oil spill also is viewed with trepi- dation by the coastal Inupiat, even though no such spill has yet occurred. These threats are accumulate because they in- teract with other factors such as climate change and because they are repeated with every new lease sale. On-land subsistence activities have been affected by the reduction in the harvest area in and around the oil fields. The reductions are greatest in the Prudhoe Bay field, which has been closed to hunting, and in the Kuparuk field, where the high density of roads, drill pads, and pipelines inhibits travel by snow machine. The reduction in area used for subsistence is most significant for Nuiqsut, the village clos- est to the oil-field complex. Even where access is possible, hunters are often reluctant to enter oil fields for personal, aesthetic, or safety reasons. There is thus a net reduction in the available area, and this reduction continues as the oil fields spread. Although there has not yet been industrial activity in the Arctic National Wildlife Refuge, proposals to explore and develop oil resources there have resulted in perceived risks to the Gwich'in culture that are widespread, intense, and themselves are accumulating effects (Chapter 9~. The Gwich'in have a centuries-old nutritional and cultural rela- tionship in Alaska and the Yukon Territory with the Porcu- pine Caribou Herd. Most view petroleum development in the 1002 Area of the Arctic National Wildlife Refuge as a threat to the herd and, thereby, to their cultural survival. The threats accumulate because there have been repeated at- tempts to develop the area and there is continuing pressure to do so.

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MA JOR EFFECTS AND THEIR A CCUMULA TION Aesthetic, Cultural, and Spiritual Consequences Many activities associated with petroleum development have changed the North Slope landscape in ways that have had aesthetic, cultural, and spiritual consequences that accu- mulate. The consequences have increased along with the area of tundra affected by development, and they will persist for as long as the landscape remains altered. Roads, pads, pipelines, seismic-vehicle tracks, and transmission lines; air, ground, and vessel traffic; drilling activities; landfills, housing, processing facilities, and other industrial infrastructure have reduced opportunities for solitude and have compromised wildland and scenic values over large areas (Chapter 9~. The structures and activities also violate the spirit of the land, a value that is reported by some Alaska Natives to be central to their culture. Given that most of the affected areas are not likely to be rehabili- tated or restored to their original condition, those effects will persist long after industrial activity has ceased on the North Slope. DAMAGE TO TUNDRA FROM OFF-ROAD TRAVEL The tundra on the North Slope has been altered by ex- tensive off-road travel, some of which may not be directly related to oil and gas activity. Networks of seismic-explora- tion trails, ice roads, pads, and all-terrain vehicle trails cover large areas. The currently favored three-dimensional seis- mic surveys require a high spatial density of trails, and the potential damage is substantial because larger camps and more vehicles are used than were used previously for two- dimensional exploration. Although the technology for ac- quisition of seismic data continues to improve, damage has not been totally eliminated, and some areas have been ex- plored repeatedly sometimes revisits to gather more com- plete data using new and better technologies; sometimes to gather data already gathered by a competitor who did not share the proprietary information. Some seismic-exploration effects accumulate because areas are revisited before the tundra recovers from previous surveys. Seismic exploration can damage vegetation and cause erosion, especially along stream banks. In addition, because seismic trails are readily visible, especially from the air, they affront the residents and degrade the visual experi- ence of the landscape. Data do not exist to determine the period that the damage will persist, but some effects are known to have lasted for several decades (Chapter 7~. Seismic exploration is expanding westward into the National Petroleum Reserve-Alaska and southward into the foothills of the Brooks Range. Current technology and gov- ernment regulations will not prevent damage to the tundra. Moreover, exploration will be conducted in regions where the topography is more complex and where permafrost con- ditions are more variable and less well known than on the Arctic Coastal Plain, where most exploration has been done (Chapter 5~. The nature and condition of permafrost in the 157 Brooks Range foothills is poorly characterized, and the hilly topography increases the likelihood that vehicles will dam- age vegetation, especially on knolls and riverbanks, causing increased erosion, exposing bare soil, and promoting devel- opment of thermokarst. This exploration will probably be carried out in a warming climate, with milder winter tem- peratures. It is hard to predict the consequences of vehicular traffic in winter on tundra under those conditions. ROADS Roads have had effects as far-reaching and complex as any physical component of the North Slope oil fields. In addi- tion to covering tundra with gravel, indirect effects on vegeta- tion are caused by dust, roadside flooding, thermokarst, and roadside snow accumulation. The effects accumulate and in- teract with effects of parallel pipelines and with off-road ve- hicle trails. The measurable direct effects covered approxi- mately 4,300 ha (10,500 acres) in the developed fields, not including indirect effects of the Dalton Highway. Roads also alter animal habitat and behavior and can increase access of hunters, tourists, and others to much of the region; enhance communication among communities; and increase contacts between North Slope communities and those outside the area. EFFECTS ON ANIMAL POPULATIONS Animals have been affected by industrial activities on the North Slope (Chapter 8~. Bowhead whales have been displaced in their fall migration by the noise of seismic ex- ploration. The full extent of that displacement is not yet known. Some donning polar bears have been disturbed. The readily available supply of food in the oil fields has resulted in the persistence of higher-than-normal densities of preda- tors, such as brown bears, arctic foxes, ravens, and glaucous gulls. Those animals are important predators on nests, nest- lings, and fledglings of many bird species, and the reproduc- tive success rate of some bird species in the developed parts of oil fields has been reduced to the extent that it is insuffi- cient to balance mortality. Serious efforts have been made, in the form of educating workers, fencing dumps, and using animal-proof waste receptacles, to reduce the amount of supplemental food available to predators. Those efforts have been only partly successful; some predators have become expert at accessing garbage and it is difficult to persuade people to stop feeding them. Reproductive rates of some bird species are, at least in some years, insufficient to balance mortality. That is, they are "sink populations" whose densities have been maintained only by steady immigration from "source" areas where reproduc- tive rates exceed mortality. As industrial activities continue to expand, increasing numbers of sink areas are likely to be cre- ated and more and more source areas are likely to be degraded. Ecology theory and empirical data indicate that populations can decline suddenly if source areas are significantly degraded.

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158 How industrial activity interacts with source-sink popu- lation dynamics is difficult to assess because local population studies alone, no matter how detailed, cannot detect all ef- fects. To anticipate and predict sudden population decline from disrupted source-sink population dynamics, analyses must focus on those species most likely to be affected, and studies must gather specific kinds of data. The number of vul- nerable species cannot be determined because demographic information does not distinguish source and sink habitats, but several species of birds could be adversely affected. As a result of conflicts with industrial activity during calv- ing and an interaction of disturbance with the stress of sum- mer insect harassment, reproductive success of Central Arctic Herd female caribou in contact with oil development from 1988 through 2001 was lower than for undisturbed females, contributing to an overall reduction in herd productivity. The decrease in herd size between 1992 and 1995 may reflect the additive effects of surface development and relatively high insect activity, in contrast to an increase in the herd's size from 1995 to 2000, when insect activity was generally low. Although the accumulated effects of industrial development to date have not resulted in large or long-term declines in the overall size of the Central Arctic Herd, the spread of industrial activity into other areas that caribou use during calving and in summer, especially to the east where the coastal plain is nar- rower than elsewhere, would likely result in reductions in re- productive success, unless the degree to which it disturbs cari- bou could be reduced. Without specific information on the exact nature of future activity and its precise distribution, it is not possible to predict to what degree distribution and produc- tivity of caribou herds would be affected. OlL SPILLS Major oil spills have not occurred on the North Slope or in adjacent oceans as a result of operations there. There have been three major spills from the North Slope segment of the Trans-Alaska Pipeline. Many small terrestrial spills have oc- curred in the oil fields but they have not been frequent or large enough for their effects to have accumulated. They have contaminated gravel, which has been difficult to clean up and has made the gravel unavailable for rehabilitation. The threat of a large oil spill especially offshore is a major concern among North Slope residents. This continu- ing concern is an accumulating effect. The effects of a large oil spill at sea, especially in broken ice, would likely be sub- stantial and accumulate because of the fluid environment and the inadequacy of current methods to remove more than a small fraction of spilled oil. ABANDONED INFRASTRUCTURE AND UNRESTORED LANDSCAPES The oil industry and regulatory agencies have made dra- matic progress in slowing the accumulation of effects of CUMULATIVE EFFECTS OF ALASKA NORTH SLOPE OIL AND GAS gravel fill by reducing the size of the footprint required for many types of facilities and by substituting ice for gravel in some roads and pads. They also have directed some atten- tion to rehabilitating or restoring already-disturbed sites. Despite this, only about 1 % of the habitat affected by gravel fill on the North Slope has been restored. Other than for well- plugging and abandonment procedures, state, federal, and local agencies have largely deferred decisions about the na- ture and extent of restoration. The lack of clear performance criteria, standards, and monitoring methods at the state and federal level to govern the extent and timing of restoration has hampered progress in restoring disturbed sites. If resto- ration would make potential future use of a site more expen- sive or perhaps impossible, restoration is likely to be de- ferred. In addition, because so much gravel has been contaminated by petroleum spills, its reuse and the restora- tion of pads and roads could be constrained because of the added difficulty of restoring contaminated sites. There also is potential liability that constitutes a barrier to reuse of con- taminated gravel. Surface structures pose problems, but there also are por- tions of the Trans-Alaska Pipeline that are buried. The pipe- line connecting Alpine to Prudhoe Bay runs under the Colville River. The vulnerability of those buried pipes to shifting river channels and their removal after production ceases could pose serious problems. By the time restoration becomes more practical be- cause better methods are available and because the opera- tional value of the sites has diminished, the revenue flow from oil and gas also will have declined. The large, well capitalized multinational oil companies are likely to have sold off substantial parts of their operations to smaller com- panies with more limited resources. Because the obligation to restore abandoned sites is unclear, and because the costs to restore abandoned sites are likely to be very high, the committee judges it unlikely that most disturbed habitat on the North Slope will ever be restored. Natural recovery in the Arctic is very slow, because of the cold; so the effects of abandoned structures and unrestored landscapes could persist for centuries and accumulate with effects of new structures. RESPONSE OF NORTH SLOPE CULTURES TO DECLINING REVENUES The standard of living of North Slope communities de- pends largely on a steady flow of money related to oil and gas activities. This way of life will be impossible to main- tain unless significant revenues continue to come into those communities from outside; the prospects of other sources of revenue appear to be modest. Painful adjustments can and probably will be postponed for as long as oil and gas are being extracted, but eventual adjustment is unavoid- able. The nature and extent of these adjustments will be determined by the adaptations North Slope societies have

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MA JOR EFFECTS AND THEIR A CCUMULA TION made to the cash economy made possible by oil and gas and other activities. TRADE-OFFS ARE INEVITABLE Continued expansion will exacerbate existing effects and create new ones. Whether the benefits derived from oil 159 and gas activities justify acceptance of the foreseeable and undesirable cumulative effects is an issue for society as a whole to debate and judge. However, if informed decisions are to be made, the nature and extent of possible effects must be fully acknowledged and incorporated into regulatory strat- egies and decision-making processes. We hope this report will assist this process.

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cow 160 Cumulative Environmental Effects of Oil and Gas Activities on Alaska 's North Slope Oil- and Gas-Related Activities and Bowhead Whales The activities most likely to affect bowhead whales are marine seismic exploration, exploratory drilling, ship and aircraft traffic, discharges into the water, dredging and island! construction, and production drilling. To date there have been documented effects of industrial noise. As was true of early censuses, the current understanding of the effects of noise on bowheads was achieved only after long efforts of Alaska Native hunters to correct early, imperfect studies (Chapter I). There have been no major offshore oil spills on the North Slope. Marine seismic exploration produces the loudest inclustrial noise in the bowhead whale habitat. Some seismic surveys are conducted in winter and spring on the sea ice, but most are done in the summer-autumn open-water period. Thus, bowheads and seismic boats are in the same areas during the westward fall migration. In the nearshore Alaskan Beaufort Sea, nearly all the fall-migrating bowhead whales avoided an area within 20 km (12 mi) of an operating vessel, and deflection ofthe whales began at up to 35 km (21 mi) from the vessel (Richardson 1997, 1998, 1999; NMFS 2002~. Noise levels received by these whales at 20 km (12 mi) were ~ 17-135 dB (NMFS 2002). Disturbance to fall migrating bowhead whales also has been shown in relation to offshore drilling in the Alaskan Beaufort Sea. At He 1992 Kuv~um site the approaching fall-migrating whales began to deflect to the north at a distance of 32 km (19 mi) east of the drilling platform and bowhead calling rates peaked at about the same distance (Brewer et al. 1 993). At the ~ 993 Kuv~um #3 site the whales were nearly excluded from an area within 20 km (12 mi) of the drilling platform (Davies ~ 997, Hall et al. 1 994). During the 1986 open-water drilling operations at the Hammerhead site, no whales were detected closer than 9.5 km (6 mi) from the driliship, few were seen closer than ~ 5 km (9 ml), and one whale was observed for 6.8 hours as it swam in an arc of about 25 km (! 5 mi) around the dr~Ish~p (LGL and Greeneridge ~ 987). The zone of avoidance therefore seemed to extend 15-25 km (9-15 mi) from the driliship. Acoustic studies done at the same time provided received levels of driliship noise that can be related to the zone of avoidance. At ~ 5 km (9 mi) from the 1986 Corona, site received sound was generally 105-125 dB (LGL and Greeneridge 1987); at km (6 mi) Mom Hammerhead, received sound was generally 105-130 dB. Estimating Future Accumulation of Effects Industrial Noise If oil- and gas-related activities continue in the Alaskan waters of the Beautort Sea, the major noise will be generated with marine seismic exploration. Other significant noise will continue to be produced by exploratory and production drilling, island construction, and vessel transit. The probable consequences are diversion of animals from their normal migratory path, possibly into areas of increased ice cover, and less use of the fall migration corndor as feeding habitat. If two or more types of disturbance occur at the same time or in the same general area, the effects could be greater than those observer! from single sources. The greatest diversion would occur if two or more seismic vessels operated simultaneously with one just offshore of the other.