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Transmission Pipelines and Land Use: A Risk-Informed Approach -- Special Report 281 (2004)

Chapter:4 Findings, Conclusions, and Recommendations

« Previous: 3 Approach for Risk-Informed Guidance in Land Use Planning
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Suggested Citation:"4 Findings, Conclusions, and Recommendations ." Transportation Research Board. 2004. Transmission Pipelines and Land Use: A Risk-Informed Approach -- Special Report 281. Washington, DC: The National Academies Press. doi: 10.17226/11046.
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4
Findings, Conclusions, and Recommendations

The United States depends on about 380,000 miles of transmission pipelines to serve a major portion of the nation’s demand for energy. These lines transport virtually all natural gas, which accounts for about 28 percent of energy consumed annually, and roughly two-thirds of petroleum products and other hazardous liquids. The system includes numerous inter- and intrastate pipeline companies, which are subject to economic and safety regulation at the federal and state levels.

The transmission pipeline safety record has been improving over time. Liquids pipelines have the best safety record of any mode, where transport options exist, for moving petroleum and other hazardous liquid products. Human casualties, property loss, and environmental damage resulting from pipeline incidents are infrequent, but when they do occur the consequences can be significant. For example, a 1999 liquids pipeline incident in Bellingham, Washington, resulted in the release of 237,000 gallons of gasoline into a stream in the middle of the city. The gasoline ignited, killing three, injuring eight, and causing roughly $45 million in property damage. Such incidents, along with population growth, urbanization, a growing demand for energy, and increased public opposition to the siting of new pipelines, have combined to focus greater attention on the need for increased land use controls in the vicinity of pipelines and led to the request for this study.

The purpose of this scoping study is to consider the feasibility of developing risk-informed guidance as one means of minimizing or mitigating hazards and risk to the public, pipeline workers, property, and the environment near existing and future transmission pipelines. The study was requested by the Office of Pipeline Safety (OPS) of the U.S. Department of Transportation to assist OPS and the Federal Energy Regulatory

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Suggested Citation:"4 Findings, Conclusions, and Recommendations ." Transportation Research Board. 2004. Transmission Pipelines and Land Use: A Risk-Informed Approach -- Special Report 281. Washington, DC: The National Academies Press. doi: 10.17226/11046.
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Commission (FERC) in developing guidance for use by state and local governments in making land use decisions near existing or proposed transmission pipelines.

FINDINGS

Finding 1. Pipeline incidents have potential for significant impact on life, property, and the environment.

According to OPS data, during the 3-year period 1999 through 2001, an annual average of 148 reportable hazardous liquids transmission pipeline incidents1 occurred, resulting in 2 deaths, 11 injuries, and $97 million in property damage. During the same time period, an annual average of 73 reportable natural gas transmission pipeline incidents occurred, resulting in 6 deaths, 10 injuries, and $20 million in property damage. In the 1990s it was estimated that more than 62 million gallons of oil and other hazardous liquids have been released into the environment. Although no comprehensive studies have yet estimated the environmental damage caused by pipeline spills in the United States, there are numerous examples of the effects of individual spills on the environment. One such example is the interstate oil pipeline rupture that occurred along the Reedy River near Greenville, South Carolina, in June 1996, which spilled almost 1 million gallons of diesel fuel into the river. An estimated 34,000 fish and other wildlife were killed, and public water supplies were threatened.

There are many other examples of pipeline incidents whose impacts are wide ranging. Box 1-1 in Chapter 1 provides a brief description of seven incidents that have occurred in the recent past in the United States.

1

A reportable pipeline incident for natural gas transmission pipelines is currently defined in 49 CFR 191 as an incident that is considered significant by the operator or that results in (a) a fatality; (b) an injury requiring hospitalization; (c) property damage, including cost of cleanup and recovery, value of lost product, and damage to the property of the operator or others, or both, of $50,000 or more; or (d) a release of gas. A reportable incident for hazardous liquids transmission pipelines is currently defined in 49 CFR 149.50 as an incident in which there is a release of the hazardous liquid or carbon dioxide transported resulting in any of the following: (a) explosion or fire not intentionally set by the operator; (b) release of 5 gallons (19 liters) or more of hazardous liquid or carbon dioxide; (c) death of any person; (d) personal injury requiring hospitalization; or (e) estimated property damage, including cost of cleanup and recovery, value of lost product, and damage to the property of the operator or others, or both, exceeding $50,000.

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Suggested Citation:"4 Findings, Conclusions, and Recommendations ." Transportation Research Board. 2004. Transmission Pipelines and Land Use: A Risk-Informed Approach -- Special Report 281. Washington, DC: The National Academies Press. doi: 10.17226/11046.
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Finding 2. Just as transmission pipelines pose a risk to their surroundings, so does human activity in the vicinity of pipelines pose a risk to pipelines. These risks increase with growth in population, urban areas, and pipeline capacity and network.


As the U.S. population continues to grow and spread out around metropolitan areas, more development is occurring near existing transmission pipeline rights-of-way. Much suburban and exurban development is taking place in outlying jurisdictions that have been among the least active in planning for and managing growth. Many such jurisdictions contain transmission pipelines that were constructed before development began. The demand for natural gas and petroleum is projected to increase by 36 percent between 2002 and 2010. Thus, more pipelines will be required to serve growing as well as mature areas.

With increasing urbanization and land development activity near transmission pipelines as well as the addition of new facilities to serve growing populations, the probability that pipelines will be damaged by human activities in the pipeline rights-of-way may also increase. In addition, if there is an incident, more people may be affected because more people may be living and working near the pipeline who have the potential to be injured or killed. This will exacerbate the consequences of an incident.


Finding 3. Land use decisions can affect the risks associated with increased human activity in the vicinity of transmission pipelines.


Many different types of land use decisions can affect pipeline safety. For example, in designing and acquiring rights-of-way, pipeline operators make decisions that affect the use of land subject to their rights-of-way. Property owners make daily decisions about how they use their land that is subject to these rights-of-way. Local governments can establish rules governing structures and uses in the vicinity of pipelines. FERC prescribes the width of new natural gas transmission pipeline rights-of-way. OPS prescribes safety practices that affect the way pipeline operators use their rights-of-way. All of these actions and decisions can affect the probability of pipeline failures and the consequences arising from incidents.


Finding 4. Pipeline safety and environmental regulation have generally focused on (a) the design, operation, and maintenance of pipelines

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Suggested Citation:"4 Findings, Conclusions, and Recommendations ." Transportation Research Board. 2004. Transmission Pipelines and Land Use: A Risk-Informed Approach -- Special Report 281. Washington, DC: The National Academies Press. doi: 10.17226/11046.
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and (b) incident response. They have not directed significant attention to the manner in which land use decisions can affect public safety and the environment.


Pipeline safety regulation is the shared responsibility of various federal and state agencies, which has resulted in a complicated regulatory system. OPS has the primary federal safety regulatory role for interstate transmission pipelines, but other federal agencies, such as the Minerals Management Service, the U.S. Environmental Protection Agency, and the Department of Homeland Security, are also involved. The states have the primary responsibility for regulating and inspecting intrastate pipelines. Federal law allows for state inspection of interstate lines as well, and Congress has provided some funding to support enhanced state efforts. Although land use regulation is vested in state police powers granted to cities and counties by their respective state legislatures, the states generally have not been active in encouraging local governments to take transmission pipelines into account in their planning and regulation of land use and development.

OPS sets all safety regulatory standards for the design, construction, operation, and maintenance of interstate pipelines and has authority to take safety enforcement action against interstate pipeline operators. The only role of states in the regulation of interstate transmission pipelines is compliance monitoring and inspections by the nine states that have been specially designated as “interstate agents” by OPS to inspect interstate natural gas pipelines and by the four states designated to inspect interstate liquids pipelines.

OPS also sets minimum standards for the design, construction, operation, and maintenance of intrastate pipelines. All 50 states regulate intrastate gas pipelines under OPS supervision. Local governments have very limited authority to regulate pipelines of any type. The only exceptions are municipalities that have the power to grant franchises or licenses to pipeline operators in order to install pipelines on public property to control the siting of new hazardous liquids pipelines. In fact, some local government proposals have gone considerably farther, often in reaction to spills and explosions, and portions of some of these proposed ordinances, which have been found to violate federal law, have been struck down under the federal preemption doctrine.

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Suggested Citation:"4 Findings, Conclusions, and Recommendations ." Transportation Research Board. 2004. Transmission Pipelines and Land Use: A Risk-Informed Approach -- Special Report 281. Washington, DC: The National Academies Press. doi: 10.17226/11046.
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Finding 5. For the most part, state and local governments have not systematically considered risk to the public from transmission pipeline incidents in regulating land use.


Transmission pipelines generally are not subject to any local land use regulation. In most instances, the width, configuration, and control of pipeline rights-of-way are established without local input. Provisions with regard to the widths of rights-of-way are often established for laying and inspecting the pipeline rather than for public safety or prevention of environmental damage. For example, a catastrophic failure of a high-pressure natural gas transmission pipeline could cause injury to people 100 feet or more away. For the largest and highest-pressure natural gas pipelines, injury is possible out to 1,000 feet, but pipeline rights-of-way are rarely more than 50 feet wide.

There is no database of land use regulatory practices in the vicinity of pipelines. In a few instances where land use measures are in effect, local governments use setbacks to protect the public from pipeline incidents. Since most communities have no land use protections in place relative to transmission pipelines, schools, apartment buildings, and hospitals are sometimes built near a transmission pipeline. Individuals whose communities have experienced explosions and major leaks indicated in presentations to the committee that land use measures involving transmission pipelines that were in existence at the time of the incident were inadequate. The few local government efforts to develop more stringent restrictions have generally been in reaction to a significant incident, a proposal to route a transmission pipeline through part of a developed area, or a plan to reactivate an inactive pipeline or convert it to carry a different commodity.


Finding 6. Risk-informed approaches are being used effectively in other domains (e.g., natural hazard mitigation, industrial hazard mitigation, nuclear reactor and waste disposal programs, tanker safety). These techniques are also being used to address other aspects of pipeline safety (e.g., pipeline integrity), but they have not been used to make informed land use decisions.


Given the relatively small number of incidents and the geographically dispersed nature of the pipeline system, the data to predict pipeline fail-

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Suggested Citation:"4 Findings, Conclusions, and Recommendations ." Transportation Research Board. 2004. Transmission Pipelines and Land Use: A Risk-Informed Approach -- Special Report 281. Washington, DC: The National Academies Press. doi: 10.17226/11046.
×

ures at a specific location with confidence are insufficient. Risks cannot be eliminated, but a risk-informed approach can help provide guidance to minimize the probability of pipeline failures occurring and to mitigate the consequences of failures when they do occur.

The committee noted that there is a lack of risk-based technical guidance for making land use decisions near transmission pipelines, but much can be learned from hazard mitigation management techniques and strategies that have been adopted by state and local governments.


Finding 7. Currently, decision makers lack adequate tools and information to make effective land use decisions concerning transmission pipelines.


Guidance concerning development that incorporates the risk from transmission pipelines is not available to local government officials. As indicated previously, the few communities that have adopted setbacks have not had access to reliable data, risk analysis, or model ordinances by which they could reasonably determine appropriate separation distances between transmission pipelines and buildings. For example, after an incident involving a liquids pipeline that led to the deaths of three teenagers in Bellingham, Washington, a proposal was made that included a 1,000-foot setback using the theoretical impact radius of a major natural gas transmission line explosion. This approach, however, considers the potential consequences of an event without accounting for its probability, is based on a natural gas pipeline failure rather than a liquids pipeline failure, and does not attempt to weigh the risk-reduction benefits of such a measure against the considerable cost that such a provision would entail.

The basic informational tools needed by local governments to adopt effective local land use measures with regard to pipeline safety are missing. For example, officials often lack accurate and complete maps showing the location and dimensions of pipeline rights-of-way or where pipelines are located within such corridors. They do not have access to any reliable scientific literature that evaluates the various risk factors, such as product transported, operating pressure, age, and depth of cover, that could affect their land use decisions. There are no model ordinances for planning, zoning, setbacks, building codes, or best practices that specifically address

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Suggested Citation:"4 Findings, Conclusions, and Recommendations ." Transportation Research Board. 2004. Transmission Pipelines and Land Use: A Risk-Informed Approach -- Special Report 281. Washington, DC: The National Academies Press. doi: 10.17226/11046.
×

transmission pipelines. The lack of accessible information may contribute to the apparent lack of attention to the risks by local officials.


Finding 8. Many different forms of pipeline easements are in effect, and the terms and conditions vary widely. To the extent that an easement lacks clarity, enforcement of the right-of-way is more difficult.


Most pipeline easements are privately negotiated agreements between a pipeline company and the owner of the land through which the pipeline passes. Many pipeline easements currently in effect were acquired many years ago, when the affected land was in agricultural use with little development. Since that time, the property may have changed hands several times, and the use of the land may have changed substantially. Provisions in these agreements depend on the time the agreement was acquired, the particular pipeline company’s practices in effect at the time the easement was acquired, the land use at the time, the difficulty of the negotiation, and any special conditions or requirements involved. Some of these easements have less specificity as to uses allowed within the easement area. To the extent that an easement lacks specificity, the pipeline operator’s task of preventing uses having the potential to harm the pipeline or compromise public safety is made more difficult. Furthermore, a particular landowner may not agree with the pipeline company’s assessment of this potential, which leads to problems with enforcement of the easement. Appropriate land use measures utilized by local governments could bolster and complement a pipeline company’s efforts to protect the right-of-way and preclude uses that could pose a public safety risk.

In addition, over time, subsequent property owners, their tenants, or the public may be unfamiliar with the terms of the agreement and may engage in activities within the easement area that are inappropriate and that could threaten the integrity of the pipeline. Inappropriate uses, such as heavy industry and landfills, buildings constructed too close to the pipeline, and the growth of mature trees on top of a pipeline, can compromise the safety of the pipeline.


Finding 9. Encroachments and inappropriate human activity within the right-of-way can adversely affect pipeline safety. There appears to

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Suggested Citation:"4 Findings, Conclusions, and Recommendations ." Transportation Research Board. 2004. Transmission Pipelines and Land Use: A Risk-Informed Approach -- Special Report 281. Washington, DC: The National Academies Press. doi: 10.17226/11046.
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be variability in the quality and extent of inspections, maintenance, and enforcement of rights-of-way.


Pipeline operators are responsible for monitoring and inspecting their own rights-of-way. Under OPS rules, they are required to inspect all pipeline rights-of-way on a regular basis and keep them clear and visible for aerial inspection. States also have varying rules for the maintenance and inspection of intrastate pipeline rights-of-way. The committee was presented with examples of inappropriate construction by property owners within easements, such as fences and home additions, which could result in major incidents. Rules governing inspection and maintenance of rights-of-way vary across jurisdictional lines, particularly for intrastate pipelines. On the basis of anecdotal evidence shown to the committee, it appears that both the public and the private sectors need to be more vigilant in determining and enforcing easement restrictions.

CONCLUSIONS

Conclusion 1. Judicious land use decisions can reduce the risks associated with transmission pipelines by reducing the probabilities and the consequences of incidents.


Pipeline safety is a shared responsibility. Land use decisions and control of activities and development near transmission pipelines may be undertaken by the pipeline operator; safety regulators; national, state, and local officials; and the property owners. Appropriate land use measures taken by local governments could bolster and complement a pipeline company’s efforts to protect the right-of-way and preclude uses that could pose a public safety risk.

Rational land use decisions that provide appropriate physical separation between people and pipelines could reduce the risk associated with increasing numbers of people in proximity to transmission pipelines. Possible land use techniques include, for example, establishing setbacks, regulating or prohibiting certain types of uses and structures (such as schools, hospitals, and apartment buildings) near transmission pipelines, and encouraging other types of activities or facilities (e.g., linear parks, recre-

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Suggested Citation:"4 Findings, Conclusions, and Recommendations ." Transportation Research Board. 2004. Transmission Pipelines and Land Use: A Risk-Informed Approach -- Special Report 281. Washington, DC: The National Academies Press. doi: 10.17226/11046.
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ational paths) within or in the vicinity of pipeline rights-of-way. Utilization of such tools can be legitimate exercises of the local authority if they are appropriately instituted, particularly if such exercises are grounded in objective, scientifically derived data.


Conclusion 2. It is feasible to use a risk-informed approach to establish land use guidance for application by local governments.


Various forms of risk-informed management of pipeline safety are already in wide use within the pipeline industry. Moreover, the “integrity management” regulations governing liquids and natural gas pipelines recently promulgated by OPS require private operators to prioritize enhanced risk-reduction efforts by using risk assessment.

The probability of failure of any transmission pipeline is a function of many distinct factors including materials of construction, fabrication, exposure to corrosion, pressurization, and depth of cover. Data and models are lacking for making precise predictions about specific lines, but estimates can be developed at an aggregate level and adjusted to account for local conditions. The possible consequences of an event could be estimated on the basis of the product carried, degree of pressurization, depth of cover, surrounding development, and other considerations. The appropriateness and acceptable cost of various measures to reduce probability and consequence could be derived from local values. Although such an approach may be somewhat simplistic initially, it could be improved over time to a sufficient degree to help government officials regulate land use. The committee envisions an ongoing process that would involve risk assessment experts and stakeholders in the development, ongoing refinement, and application of such information.


Conclusion 3. The federal government could serve a useful role by providing leadership in the development of risk-informed land use guidance for application by local, state, and federal governments.


Pipeline safety is a national issue because 1.8 million miles of pipelines traverse the United States transporting numerous products, most of which could pose a threat to life, property, and the environment were there to be a pipeline failure. Because of the numerous stakeholders

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Suggested Citation:"4 Findings, Conclusions, and Recommendations ." Transportation Research Board. 2004. Transmission Pipelines and Land Use: A Risk-Informed Approach -- Special Report 281. Washington, DC: The National Academies Press. doi: 10.17226/11046.
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concerned about pipeline safety and their divergent interests and because of the national breadth of the concerns, the federal government may be best positioned to initiate an open process of developing risk-informed guidance. OPS played a similar role in fostering and initially supporting the Common Ground Alliance. Land use policies relevant to transmission pipelines are made at all levels of government and need to be based on an unbiased, scientific analysis of the risk posed by pipelines to their immediate surroundings. Local governments generally lack the resources and incentives to undertake such a broad-based effort on their own. The advantage of consistent guidance across jurisdictional lines also argues for federal leadership.


Conclusion 4. There is clear evidence that guidelines can be developed that would assist in preserving habitat while maintaining rights-of-way in a state that facilitates operations and inspection.


As an adjunct to its main charge, the committee was asked to consider the problem of habitat loss when rights-of-way are initially cleared and subsequently maintained to allow for inspection, which is required by federal law. Right-of-way maintenance facilitates such inspection, usually conducted by aerial surveillance, and reduces the potential for tree roots to interfere with pipelines, which is another possible cause of failure. Rights-of-way can provide useful and functional habitat for plants, nesting birds, small animals, and migrating animals. In developed or urban areas, the ecological function of such rights-of-way may be useful but marginal, in large part because of the narrowness of the right-of-way and the already extensive habitat fragmentation. There is an overriding environmental benefit in effective inspection of pipelines to avoid incidents with consequent releases and environmental damage.

RECOMMENDATIONS

Recommendation 1. OPS should develop risk-informed land use guidance for application by stakeholders. The guidance should address

  • Land use policies affecting the siting, width, and other characteristics of new pipeline corridors;

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Suggested Citation:"4 Findings, Conclusions, and Recommendations ." Transportation Research Board. 2004. Transmission Pipelines and Land Use: A Risk-Informed Approach -- Special Report 281. Washington, DC: The National Academies Press. doi: 10.17226/11046.
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  • The range of appropriate land uses, structures, and human activities compatible with pipeline rights-of-way;

  • Setbacks and other measures that could be adopted to protect structures that are built and maintained near pipelines; and

  • Model local zoning ordinances, subdivision regulations, and planning policies and model state legislation that could be adopted for land uses near pipelines.

Such a risk-informed guidance system should include three interrelated components:

  1. A decision framework informed by risk analysis,

  2. Guidelines based on the analysis, and

  3. Alternative actions that could be taken on the basis of the guidelines.

Recommendation 2. The process for developing risk-informed land use guidance should (a) involve the collaboration of a full range of public and private stakeholders (e.g., industry and federal, state, and local governments); (b) be conducted by persons with expertise in risk analysis, risk communication, land use management, and development regulation; (c) be transparent, independent, and peer reviewed at appropriate points along the way; and (d) incorporate learning and feedback to refine the guidance over time.


Recommendation 3. The transmission pipeline industries should develop best practices for the specification, acquisition, development, and maintenance of pipeline rights-of-way. In so doing, they should work with other stakeholders. With regard to the specific maintenance issue of clearing rights-of-way to allow for inspection, the federal government should develop guidance about appropriate vegetation and environmental management practices that would provide habitat for some species, avoid threats to pipeline integrity, and allow for aerial inspection.

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Suggested Citation:"4 Findings, Conclusions, and Recommendations ." Transportation Research Board. 2004. Transmission Pipelines and Land Use: A Risk-Informed Approach -- Special Report 281. Washington, DC: The National Academies Press. doi: 10.17226/11046.
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Suggested Citation:"4 Findings, Conclusions, and Recommendations ." Transportation Research Board. 2004. Transmission Pipelines and Land Use: A Risk-Informed Approach -- Special Report 281. Washington, DC: The National Academies Press. doi: 10.17226/11046.
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Suggested Citation:"4 Findings, Conclusions, and Recommendations ." Transportation Research Board. 2004. Transmission Pipelines and Land Use: A Risk-Informed Approach -- Special Report 281. Washington, DC: The National Academies Press. doi: 10.17226/11046.
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Suggested Citation:"4 Findings, Conclusions, and Recommendations ." Transportation Research Board. 2004. Transmission Pipelines and Land Use: A Risk-Informed Approach -- Special Report 281. Washington, DC: The National Academies Press. doi: 10.17226/11046.
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Suggested Citation:"4 Findings, Conclusions, and Recommendations ." Transportation Research Board. 2004. Transmission Pipelines and Land Use: A Risk-Informed Approach -- Special Report 281. Washington, DC: The National Academies Press. doi: 10.17226/11046.
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Suggested Citation:"4 Findings, Conclusions, and Recommendations ." Transportation Research Board. 2004. Transmission Pipelines and Land Use: A Risk-Informed Approach -- Special Report 281. Washington, DC: The National Academies Press. doi: 10.17226/11046.
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Suggested Citation:"4 Findings, Conclusions, and Recommendations ." Transportation Research Board. 2004. Transmission Pipelines and Land Use: A Risk-Informed Approach -- Special Report 281. Washington, DC: The National Academies Press. doi: 10.17226/11046.
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Suggested Citation:"4 Findings, Conclusions, and Recommendations ." Transportation Research Board. 2004. Transmission Pipelines and Land Use: A Risk-Informed Approach -- Special Report 281. Washington, DC: The National Academies Press. doi: 10.17226/11046.
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Suggested Citation:"4 Findings, Conclusions, and Recommendations ." Transportation Research Board. 2004. Transmission Pipelines and Land Use: A Risk-Informed Approach -- Special Report 281. Washington, DC: The National Academies Press. doi: 10.17226/11046.
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Suggested Citation:"4 Findings, Conclusions, and Recommendations ." Transportation Research Board. 2004. Transmission Pipelines and Land Use: A Risk-Informed Approach -- Special Report 281. Washington, DC: The National Academies Press. doi: 10.17226/11046.
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Suggested Citation:"4 Findings, Conclusions, and Recommendations ." Transportation Research Board. 2004. Transmission Pipelines and Land Use: A Risk-Informed Approach -- Special Report 281. Washington, DC: The National Academies Press. doi: 10.17226/11046.
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TRB Special Report 281: Transmission Pipelines and Land Use: A Risk-Informed Approach calls upon the U.S. Department of Transportation's Office of Pipeline Safety in the Research and Special Programs Administration to work with stakeholders in developing risk-informed land use guidance for use by policy makers, planners, local officials, and the public.

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