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s ENVIRONMENTAL CONSIDERATIONS . . The installation and operation of offshore platforms has attracted environmental attention for almost 40 years. From a historical perspective, concerns, whether focused on the issue of offshore leasing or on the environmental effects of drilling and production operations, have been addressed through the regulatory process and environmental law. Environmental concerns associated with the disposition of offshore platforms are relatively new since only a small number of structures have been removed. To define the conse- quences and concerns, leading spokesmen from environmental interest groups were surveyed, and public comments were obtained by the Minerals Management Service (MHS) on the committee's behalf (see preface and Appendix B.). Disposing of offshore structures results in both positive (enhance- ment) and adverse (disruption) environmental impacts. The positive impacts are related to potential fisheries aggregation and enhancement values of structural elements left in the marine environment. Poten- tial adverse concerns include continuing navigational risks (which could lead to pollution damage) as well as the appropriate cleaning of structures, their physical removal, resulting bottom clean-up, the logistics associated with transport, and ultimate disposition. While each of these potential impacts is a subject of environmental concern, properly executed disposition was not cited as a major problem by those surveyed. Indeed, commentors expressed as much concern for .~ Records of the following telephone conversat ions are in cocci t tee files. Randy Lanctot, Louisiana Wildlife Federation, S December 1984; Marsha Rockefeller, Massachusetts Aububon Soc iety, S December 1984; Herman Rudenberg, Lone Star Chapter , S terra Club, 5 December 1984; Hal Scott, Department of Interior OCS Policy Advisory Committee, 21 December 1984; Sharron Stewart, Texas Environmental Coalition, 21 December 1984; Michelle Perrault, Sierra Club, 13 January 1985; Sarah Chasis Natural Resources Defense Council, 17 January 198S; Ralph Rayburn, Texas Shrimp Association, 25 March 198S; and David Hickok, Alaska Environmental Information Data Center, 27 March 1985. See also letters from Sarah Chasis dated 26 April 1985 and David Hickok dated 30 April 1985. 45

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46 habitat loss as for all other impacts associated with disposition. This probably reflects the regional perspective of the activity in the Gulf of Mex i co . Env i ronmental concerns were expres sed as to the mortgaging of future opportunities at the expense of simple or cost-effective platform removal options. For example, deep-water disposal was generally considered shortsighted, recognizing potential future impacts on other ocean users. Toppling in place received similar expressions of concern, because reviewers were reluctant to make the ocean a "junkyard." While disposition options received a broad array of environmental expressions, they were often regionalized, reflecting historical perspectives as well as the economic consequences apprec~- ted by the respective respondents. EFFECT OF OFFSHORE PLATFORMS ON BIOLOGICAL RESOURCES When offshore structures are installed, they are colonized by a diversity of marine life. These may include barnacles, oysters, mussels, bryozoans, sponges, and (in subtropical or tropical waters) corals. These organisms attach and grow on the structure and provide a source of food and habitat for many invertebrates and fishes. Collectively, these life forms comprise the structure's biofouling community (Galloway and Lewbel, 1982~. This community typically supports an assemblage of pelagic and demersal fishes that, in certain circumstances, has implications for recreational and commercial fisheries. A diversity of fishes can be associated with offshore structures. As Galloway and Lewbel point out: The available data and information about these characteristic fish assemblages seem to indicate that they are more dictated by the physical factor of substrate than by biological inter- relationships. If this is true, the fish assemblages associa- ted with petroleum platforms are not true biological commun;- ties, but rather only flexible confederations of species loosely allied by a similar environmental requirement or preference, i.e., the presence of structures. The fisheries aggregation and enhancement values of offshore oil and gas structures are well recognized in the Gulf of Mexico region. Interests outside the Gulf of Mexico region, however, have questioned these enhancement values in their respective regions. For example, state agency officials on the east and west coasts generally consider oil and gas structures as obstructions to navigation and commercial fishing interests, and take positions that protect these traditional industries. The diversity of regional perspectives is perhaps a reflection of the historical experiences of commentators as well as the uniqueness of regional fishery resources. Petroleum platforms in the Gulf of Mexico serve as aggregation

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47 points for large numbers of fish of many species. However, the extent to which this aggregation increases exploitation (greater catch par unit of effort), possibly to the point of overexploitation, is of concern to fisheries managers. Where reefs enhance fisheries, manage- ment regimes are necessary to avoid this possibility. States with active offshore development (i.e., Louisiana and Texas) are now concerned that when production ceases, they may lose valuable fisheries habitat (in place or emplaced elsewhere) and are working to identify critical habitat areas. Some states bordering the Gulf of Mexico, including some without offshore oil and gas development, are working to secure obsolete structures for deployment as artificial reefs off their coasts. ENVIRONMENTAL RAMIFICATIONS OF DISPOSAL OPTIONS Complete Removal With Disposal Onshore When a structure is removed from the OCS, as under current regula- tions, organisms that have attached and grown on the structure are destroyed. Also, the substrate that has attracted important recrea- tional and commercial fisheries is lost. As these losses occur, the fish are attracted elsewhere for food and shelter. Fishermen likewise must seek new fishing locations that are within their operational constraints. The significance of these losses is perhaps best under- stood in light of a proposal several years ago to have the Shell Oil Buccaneer Field designated a marine sanctuary. Though the associated marine life is attached to the man-made structures, the reef-like communities are comparable to natural reefs and, it can be argued, worth keeping as a sanctuary area. During onshore dismantling opera- tions, there is the possibility of air pollution and environmental degradation. There are opportunity losses, as well. At a time when suitable reef materials are in short supply, onshore disposal eliminates the possibility entirely that these materials can be used as reefs. There are, however, gains associated with onshore disposal. Not the least of these is the removal of a potential hazard to naviga- tion. When the structure is removed for transport to shore, the bottom is to be restored so that trawl fishermen can again make use of the site without the prospect of destroying their nets. If the structure was in an area once heavily used for trawling, this gain can be an important benefit. The "remove to shore" alternative is almost universally favored by environmental interests located outside the Gulf of Mexico area who reject the reef benefits of structures as not relevant to circumstances in their regions. This option is also favored by fishermen who use new gear types that may be adversely affected by underwater obstructions. Included here are such items as bottom longlines, deep-water traps, and underwater trawls. Some of this gear may be used in depths as great as 1,000 meters.

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48 Ocean Dumping of Obsolete Structures A letter to the committee from the Environmental Protection Agency (EPA) states that the EPA has a policy of recycle and reuse of offshore platforms. This includes the options of onshore disposal (with recycling of salvaged materials) and the use of platforms as artificial reefs once removed from the production site. Ocean disposal of offshore platforms has to date only been permitted where safety is an issue or there has been an emergency. In February 1984, for example, SPA issued a permit for ocean disposal of a platform that had been damaged as the result of collision with a tanker in 1980. The current practice, therefore, is to place the burden of proof on the platform owner to demonstrate why reuse and recycling are not feasible, that the public safety is threatened, and that there is good and sufficient reason for ocean disposal as an alternative of last resort. However, the letter from EPA does state, "We are considering a general permit for those platforms or jackets damaged by storms or collision, etc. and [which] are creating a hazard to navigation as determined by the Coast Guard and/or the Corps of Engineers, and [for which] disposal in a better location would be more advantageous " Environmental spokesmen generally opposed ocean dumping of obsolete platforms, or they expressed caution because of a lack of informa- tion. Most viewed it as misusing the ocean as a "junkyard" and saw platform disposal as a bad precedent. They were deeply concerned with safety and navigation hazards because of the potential environmental harm that often accompanies accidents. Consequently, there was little support for ocean dumping of structures except as an emergency provi- sion. Those who believe that artificial reefs are in the public interest argued that dumping is a poor use of materials that could otherwise be used as reef building material. Ocean dumping is regulated under the EPA Ocean Dumping Regulations and Criteria (40 CFR 220-229), as has been described. Specific environmental concerns are addressed through requirements for siting, predisposal cleanup, and monitoring. The general concern about conflict with other ocean uses is not so eas fly addressed. The practice of ocean dumping, even if carefully sited and controlled, could preclude future deep-sea mining and fishing activities, for example . A related point of interest is the disparity in the environmental policy and requirements that apply to the disposition of offshore structures as compared with those that apply to the disposition of obsolete ships. A general permit for the ocean disposal of obsolete ships is in effect (40 CFR 229.3). The terms of the permit require that (except in emergencies) the dumper provide advance notice to the EPA, that the operation be supervised by the Coast Guard, and that the vessel be cleaned of possible pollutants. Other requirements of the Letter of 27 November 1984 from Tudor Davies, EPA to W. M. Benkert.

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49 general permit pertain to the choice and charting of sites for disposing of ships and the method of sinking. The Leave-in-Place Option The leave-in-place option is not feasible given legal requirements for the removal of obsolete structures. There has been public support for this option as evidenced by an EMS notice of interpretation published in the Federal Resister (Notice of Interpretation, 1983~. Generally speaking, when a platform is left in place the reef-like community that has developed on the structure remains to sustain fish populat ions at all levels in the water column . As substrate in the water column is removed, environmental benefits are lost. While the leave-in-place option is biologically appealing, there are questions as to who will bear the liability and funding responsibilities for maintenance. There are concerns about navigational hazards and a need to restore trawlable bottoms for commercial fishermen Some of the environmental spokesmen were skeptical and saw the leave-in-place option as providing the oil and gas industry with unwarranted and uncompensated relief from a major (and costly) obligation. Environmental spokesmen in the Gulf of Mexico recognized that existing structures provide important habitat benefits and that efforts should be made to perpetuate these benefits. While existing structures all provide substrate and a reef community to some extent, depending on the age and location of the structure, it is recognized that they do not all provide the same level of fisheries benefits. This was supported in a recent study by Ditton and Auyong (1984) which showed that all structures do not receive the same level of use. Some, because of their proximity to shore access points, are used more by recreational f ishermen than others located further offshore. A case can be made for limited application of this option in the Gulf of Mexico. The leave-in-place option would be appropriate in close proximity to an onshore recreational fishing access point (10 to 20 miles offshore) or where extensive recreational fishing use is documented. The exclusion mapping procedures developed by the Sport Fishing Institute (Anon., 1984) currently being implemented in the Gulf of Mexico with support from the National Marine Fisheries Service, are useful for identifying the structures that have the greatest probability of use and where conflict with other marine U9QS can be avoided. This option merits consideration to the extent that liability and maintenance issues are handled, conflicts with other uses of ocean space are avoided, and constituent support is demon- strated. The Partial Removal Options The partial removal options are accompanied by the losses of substrate-related reef community and a diverse fishery. Though fisheries would continue to be enhanced to a limited degree, partial

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50 removal in some instances would reduce the public benefits associated with recreational fishing activity. Only fishermen with radio naviga- tion capability would be able to locate and fish the habitat, unless the art i f i c i al reef was marked wi th a buoy, wh i ch would need to be maintained. Commercial fishermen would likely be opposed to any removal options that would exacerbate the problem of bottom hangs and debris on the bottom. Under the partial removal option, there would either be little recreatonal fishing because of the distance from shore required to attain the necessary navigation clearance, or, in the case of structures closer to shore, there would be little profile remaining to support a diverse fish population. The Topple-In-Place Option When an obsolete structure is toppled, the resultant benthic reef would have a much less diverse fishery than previously when the struc- ture was in place and provided substrate at all depths. The topple- in-place option could lead to a distribution of additional materials on the bottom that could lead to increased snagging of fishermen's nets. Commercial fishermen would favor the restoration of trawlable bottoms. Persons contacted by the committee with ~ knowledge of structures in the Gulf of Mexico and their associated enhancement benefits felt that the topple-in-place option could pose a hazard to navigation as well as problems for commercial fishermen. To the extent that toppling in place could be implemented judiciously following established procedures (Sport Fishing Institute, 1984) for artificial reef planning, this opposition could be overcome. The Emplace Elsewhere Option To date , there have been three cases where obsolete oil and gas structures have been removed, transported to a new location, and deployed as a reef for fishing enhancement purposes at a permitted site. Although there are environmental costs associated with the conversion of a standing platform to a benthic reef, there are numerous benefits as well if reef deployment is conducted in a well-planned manner. If platform reefs are sited on the basis of the best combination of physical, biological, social, and economic considerations rather than expedience, tangible benefits are likely. When a platform is removed and redeployed as a reef near a major population center or tourism destination in conjunction with a formal plan, economic benefits associated with increased recreation and tourism activity will be forthcoming for the adjacent community. The economic impacts associated with artificial reefs are well documented in the technical literature. Environmental spokesmen in the Gulf region favored this option because they were aware of the biological and economic benefits involved. They also appreciate the reduction of user conflicts that occurs as a result of the permitting process.

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51 Environmental spokesmen outside the Gulf area generally rejected these benefits, primarily because of the lack of demand for reef development to enhance fisheries or because the concept was considered inappropriate to their regions. To the extent that obsolete structures are poorly sited as reefs and public use benefits are limited, it can be argued that this option is often little more than ocean dumping. To avoid misuse of the emplace elsewhere option, the state of the art of artificial reef planning needs to be improved. In this regard there are several positive forces at work: (1) the recently passed National Fishing Enhancement Act (P.L. 98-623), (2) the National Artificial Reef Plan to be implemented as a result of this Act, (3) the work of the National Artificial Reef Development Center of the Sport Fishing Institute to rationalize the reef planning process, and (4) the general permit for artificial reef development recently developed in the Jacksonville , Florida office of the U.S. Army Corps of Eng i nears ~ There appear to be fewer problems associated with the emplace elsewhere option. Liability problems remain to the extent that the reef deviates from permit requirements. Siting problems can be over- come through communication and negotiation in the permitting process. Funding still presents problems for the reef sponsor as well as the oil company with a disposal problem. Mechanisms are needed for funding reef maintenance in perpetuity. Likewise, oil companies need incentives above and beyond "good public relations" to implement this disposal option on a long-term basis. This option is likely to be pursued only to the extent that the cost to the structure owner for artificial reef development does not exceed the cost of other options. REGIONAL CONSIDERATIONS Support for reuse of offshore structures is limited primarily to the Gulf of Mexico because that is where the problems and the oppor- tunities lie. There are no offshore oil platforms in the Atlantic OCS to date. While 14 platforms in Alaska state waters are approaching retirement, the waters themselves are heavily laden with glacial silt and subject to high currents. The platforms do not support local fish populations, and there is no recreational fishery around them. Off California, the number of current and projected offshore platforms is small, in relation to the Gulf of Mexico. Thus, the size of the recreational fishery that targets the platforms is also much smaller. It should be noted, however, that at least one company harvests mussels off California platforms for sale to restaurants. Decisions on ultimate disposition should properly reflect environ- mental benefits and costs on a case-by-case basis. Where intensive letter and attachment from David M. Hickok, Alaska Environmental Information Data Center, to C. A. Bookman, Marine Board, dated 30 April 1985.

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52 recreational fishing use can be documented (and where there are no other structures available to attract fish), where important regional economic impact losses are foreseen due to removal, and where constituent pressure is brought to bear, alternatives to onshore disposal should be considered. Competing uses of the area for commercial fishing and navigation need to be fully considered as well. For the foreseeable future, the coloration of aging platforms with this combination of circumstances is found only in portions of the Gulf of Mexico. Under other circumstances in other regions, it may be appropriate to consider innovative uses of obsolete platforms--for example, for weather observation, mariculture fisheries, and research. REFERENCES Ditton, Robert 8., and Janice Auyong. 1984. Fishing Offshore Platforms--Central Gulf of Mexico: An Analysis of Use at 164 Major Petroleum Structures . Iletairie, La.: Minerals Management Service. OCS Monograph MMS 84-0006. Ditton, Robert B., and Alan Graefe. 1977. Recreational Fishing Use of Artificial Reefs on the Texas Coast. Prepared for the Texas Coastal and Marine Council, Austin, Texas. Contract Report (77-79) 080S. Galloway, Benny J., and George Lewbel. 1982. The Ecology of Petroleum Platforms in the Northwestern Gulf Of Mexico: A Community Profile. New Orleans, La.: Bureau of Land Management, Gulf of Mexico OCS Regional Office. Open File Report 82-03. Anon . 1984 . Procedures for Exclus ion Mapping to Guide Future State-Level and Local Artificial Reef Planning and Siting Efforts in the Gulf of Mexico. Washington, D.C.: Sport Fishing Ins t i tute . Unpubl i shed Report . Notice of Interpretation. FR Yol. 48, No. 132, 81 July 1983. Department of Interior, Minerals Management Service . 30 CFR Part 250, OCS; Interpretation Concerning Authority to Depart from OCS Requirements. Signed 29 June 1983 by David C. Russell, acting director of Minerals Management Service. U. S. Congress, Public Law 98-623. National Fishing Enhancement Act of 1984 .