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Practical Lessons from the Loma Prieta Earthquake (1994)

Chapter: 1. Legacy of the Loma Prieta Earthquake: Challenges to Other Communities

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Suggested Citation:"1. Legacy of the Loma Prieta Earthquake: Challenges to Other Communities." National Research Council. 1994. Practical Lessons from the Loma Prieta Earthquake. Washington, DC: The National Academies Press. doi: 10.17226/2269.
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1
Legacy Of The Loma Prieta Earthquake: Challenges To Other Communities

L. Thomas Tobin

INTRODUCTION

The National Research Council and Earthquake Engineering Research Institute are to be congratulated for conceiving and sponsoring a symposium on practical lessons from an earthquake. Far too often, we treat earthquakes as abstract laboratories of scientific curiosity, as events that raise questions and provide opportunities for further studies. Focusing on practical lessons is a start, but our object should be, as with all lessons, to translate them into action that reduces risk.

The charge to each of us attending this symposium is to determine how we can apply our knowledge to reduce risk. The Loma Prieta earthquake and other earthquakes before and since have left us a legacy of information. I think we are all generally aware that we possess the knowledge to reduce earthquake risk across the nation. If a general reduction of risk is to be our legacy, however, we must embed our information, knowledge, and understanding in public policy.

We are doing relatively well in synthesizing information and knowledge into understanding. However, while each day brings more understanding of earthquakes, soil types, materials, and designs, policies that implement this increased understanding are not advancing as fast. We all must learn how public policy is created. We must expand our scope of collegiality and become active policy advocates. The future cannot afford our comfortable and exclusive association with other engineers and scientists. We must add building officials, city councils, boards of supervisors, and state legislators as colleagues to a broadened endeavor. We know how to build a bridge to resist earthquakes, now we have to

Suggested Citation:"1. Legacy of the Loma Prieta Earthquake: Challenges to Other Communities." National Research Council. 1994. Practical Lessons from the Loma Prieta Earthquake. Washington, DC: The National Academies Press. doi: 10.17226/2269.
×

learn how to build a bridge to policy makers to ensure that only safe bridges are built.

The current strategy employed by the National Earthquake Hazard Reduction Program (NEHRP) is to support research. Others, working in state and local government, are expected to implement the results of their research through concrete actions. Unfortunately, this approach does not lead to substantial progress in coping with our vulnerabilities to earthquakes. Trickle-down mitigation works no better than trickle-down economics.

THE NEED TO REACH OUT

The Loma Prieta earthquake provided a perspective different from earthquakes in Mexico City, Armenia, Ferndale, Landers, and Whittier. After observing damage in my home town and talking to families of victims, I was ashamed that we had not fully used what we knew. We are all culpable for failing to use our knowledge to effect change. We spend too little time using what we know to change public policy. I recognize that many of you fully use available knowledge in your practice, but most of us expect others to change public policy. This is the fundamental flaw in our efforts; ignoring public policy is an abdication of our responsibility. We are failing in this, our ultimate job, by not swaying those whose decisions affect public and corporate policy.

We also are not reaching our colleagues. Look around this room. You do not see 99 percent of the 560 building officials in California, 99 percent of the practicing civil engineers, architects, or engineering geologists. How do we reach these people? Who is responsible for reaching them? It's not the other person; it's you and me. It's our responsibility to use what we know to foster widespread professional training.

Our challenge is to reach those who are not here, to teach other professionals, and to sway policy makers. You can press these ideas in your professional societies; before boards of registration; and by serving on advisory committees, planning commissions, and city councils. You can demand mandatory professional education. You can influence your elected representatives. You can use your knowledge to see to it that earthquake risk is reduced.

THE NEED FOR SUSTAINED ADVOCACY

The Loma Prieta earthquake reinforced common-sense wisdom that there is a ''window of opportunity'' for seismic safety advocacy in the aftermath of an earthquake. One must be ready with proposals for state and local legislation and private-sector clients. The earthquake left a legacy of new and enhanced public and private programs begun during the window of opportunity:

  • The California legislature considered over 300 seismic bills. They created a new seismic hazard mapping program, a prepaid residential recovery fund,

Suggested Citation:"1. Legacy of the Loma Prieta Earthquake: Challenges to Other Communities." National Research Council. 1994. Practical Lessons from the Loma Prieta Earthquake. Washington, DC: The National Academies Press. doi: 10.17226/2269.
×

and an earthquake deficiency disclosure requirement for residences and certain commercial buildings; placed a $300 million bond measure on the ballot (which passed when other bond measures failed); and required the California Department of Transportation—CALTRANS—to retrofit existing vulnerable bridges.

  • The cities of San Francisco, Los Angeles, Berkeley, and Oakland passed general obligation bond measures to retrofit certain buildings and improve emergency response capabilities. The state and Santa Cruz County temporarily raised sales taxes to pay for repair and retrofit.

  • Statewide, many cities and counties accelerated their efforts to comply with the state law that requires the identification of unreinforced masonry buildings, the notification of owners, and the adoption of mitigation programs. Only 32 jurisdictions had adopted unreinforced masonry (URM) mitigation programs on October 17, 1989; nine months later the total was 154. Today 286 or 78 percent of the affected jurisdictions are in compliance with the law. Over half of the jurisdictions have programs in place that require owners to retrofit or raze their buildings within a specified time.

  • The cities of Alameda, Palo Alto, and Santa Clara have entered into a mutual-aid agreement with the southern cities of Burbank, Glendale, and Pasadena to share personnel and equipment needed for the repair of municipal utilities. According to the agreement, the cities needing assistance would pay for personnel, transportation, and materials sent by the responding cities.

  • The state Office of Emergency Services has established a heavy search and rescue capability and is now installing the "OASIS" satellite communications system, which links key state agencies with county emergency operation centers.

  • The private sector's response also has been impressive. Businesses in southern California and in the Bay Area have acted to retrofit their buildings, diversify their production, and prepare for their emergency response and business recovery.

California took advantage of the "window of opportunity" to make a number of long-term advances, because it had an existing advocacy program and a plan. Waiting for a window of opportunity is no substitute for ongoing, persistent policy advocacy. The window may not open very wide, and it will not remain open for long.

  • Even in late 1989 and early 1990, before the dust of the Loma Prieta earthquake had settled, the economy and budget loomed as the most important issues in Sacramento. The legislature would not deal with a number of seismic issues, because their priority was recovery, not mitigation.

  • Not every policy body will act while the "window of opportunity" is open. Nearly 100 cities and counties still have not adopted URM mitigation programs and are out of compliance with a state law passed three years before the Loma Prieta earthquake. Another 100 have either voluntary or notification-only programs, which, though nominally in compliance, are ineffective.

Suggested Citation:"1. Legacy of the Loma Prieta Earthquake: Challenges to Other Communities." National Research Council. 1994. Practical Lessons from the Loma Prieta Earthquake. Washington, DC: The National Academies Press. doi: 10.17226/2269.
×
  • Carrying out and sustaining advances is proving more difficult than creating new programs. An economy in recession all but closed the window in California by 1991, and now we are learning that policy gains are not necessarily permanent.

  • Performance is not guaranteed. Even when programs are established and underway, there needs to be a constant push for performance and a demand for accountability. Following the Loma Prieta earthquake, a state agency decided that the state should lease buildings with a reasonable chance of withstanding earthquakes. They proposed a policy to that effect in 1990. Unfortunately, because of retirements in the ranks and a change in administration with new leadership, the proposal was lost in an institutional limbo for nearly two years.

The "political mood" related to the economy also has undermined a number of our gains. Private businesses and local and state governments are cutting back substantially; they cannot afford "too much" safety. We are experiencing an erosion of our advances.

  • The California Residential Earthquake Recovery Fund was repealed. The opposition, driven largely by insurance industry political interests, was unable or unwilling to stop passage in 1990, but just two years later, the climate had changed, and fear that claims might exceed resources in the fund was greater than the concern for future earthquake victims. A majority of legislators voted for repeal.

  • There is an ongoing effort to emasculate the 60-year-old Field Act. Until now, our schools could be counted on to protect children and provide emergency shelter. That may change.

  • In virtually every local government, budget cuts are significantly reducing the ranks of professional emergency managers. We may be saving pennies for our future, but at what hidden price?

  • The Seismic Safety Commission faces budget hearings in which there is the distinct possibility that funding for the Commission will be eliminated.

Thus, while the "window of opportunity" does exist, and while we should be ready to take advantage of it, it is far more important to build a sustained advocacy program. Otherwise, we may find ourselves waiting forever for the "right time."

Political and public support for earthquake risk reduction measures can be developed by making decision makers aware of the hazard; explaining the expected losses to the buildings, businesses, and functions they care about; and then explaining that there are technically and politically viable solutions and funding within existing administrative structures. The familiarity and trust that develops from a credible, long-term advocacy program is essential and even more important when the "window" is open. Sustained advocacy is essential to changing public policy and putting our legacy of knowledge to work.

Suggested Citation:"1. Legacy of the Loma Prieta Earthquake: Challenges to Other Communities." National Research Council. 1994. Practical Lessons from the Loma Prieta Earthquake. Washington, DC: The National Academies Press. doi: 10.17226/2269.
×

IRREVERSIBLE CHANGE

If we fully used available knowledge, our public policies and key programs would be logical extensions of that knowledge. However, the Loma Prieta earthquake shows this is not the case. Consider public policy relating to recovery. The earthquake caused irreversible changes: personal losses, structural losses, cost increases, different options for injured persons, disrupted businesses, and shattered neighborhoods, and it created different responsibilities for state and local governments. Accepting change runs counter to the human inclination to return as rapidly as possible to "normal," to return to "the way it was." Unfortunately, once damaged deeply enough, the community will never be the same.

Changes are not caused just by the earthquake. Pre-existing problems such as housing shortages, run-down and underused commercial areas, and lack of governmental funding are revealed and made worse by an earthquake. Needs change as well. The business climate may have changed, the building stock may have deteriorated, demands on the existing infrastructure may have grown, and jobs may have moved elsewhere. New problems, such as homelessness, narcotics-related crime, and new land uses may have changed the community. The recovery effort, especially building and infrastructure repairs, should reflect these changes and anticipate the ensuing policy and land-use disputes.

Our national disaster recovery policy, however, is unresponsive to this reality. It is crafted in a way that inhibits change and is slow to resolve controversy. Recovery policies are biased toward returning to the status quo, toward replacing what was there. They do not provide flexibility to accommodate changed conditions and needs.

Not too far from here, work is progressing on the demolition of ramps connecting city streets with the Bay Bridge. Approximately $175 million of federal money is available to replace these damaged ramps. CALTRANS fears changing the alignment will jeopardize the funds, even though San Francisco and its traffic patterns have changed greatly since the ramps were built in the 1930s. The planning director for San Francisco, Lucien Blazej, was quoted as saying, "We should be planning ahead. Rebuilding what exists today does not address that issue. [Exact replacement] is bad public policy at every level."

Post-disaster mitigation funds are insufficient to repair buildings to resist future earthquakes. Moreover, disaster programs presuppose the existence of standards that allow a consistent way to evaluate damage and determine the cost of repair. We all know standard repair codes are not available and that a "single code" cannot provide the flexibility to achieve the performance level appropriate to the use of each repaired building.

Arguments between applicants for aid and funding agencies and between proponents of the various causes are supported by professionals. Their opinions are founded on different levels of expertise, investigation, and assumptions about performance. It is a Catch-22. Disagreements over damage estimates, cost of

Suggested Citation:"1. Legacy of the Loma Prieta Earthquake: Challenges to Other Communities." National Research Council. 1994. Practical Lessons from the Loma Prieta Earthquake. Washington, DC: The National Academies Press. doi: 10.17226/2269.
×

repairs, expected performance, and changed community needs cause delay and frustration. In the end, no one is well served. Judgment and flexibility, specific to the conditions of each building and disaster, are needed to foster recovery.

Failing to resolve disagreements in a timely and flexible fashion will delay recovery, increase costs, and enrich attorneys. A conflict resolution mechanism is needed. Peer panels could be used to resolve both factual and judgmental disagreements. Binding arbitration could be used to make timely decisions. Federal agencies could give state and local governments recovery funds as block grants, requiring only that the funds be used to return the disaster area to a functioning and viable community. We need repair guidelines and standards that provide for a variety of performance levels based on the building and its intended use. A legacy of the Loma Prieta earthquake is the knowledge that the federal disaster aid program should be changed.

Rome Wasn't Built In A Day

The Loma Prieta earthquake reminded us that recovery is a long-term effort that imposes a substantial financial burden on local governments and businesses.

  • The city of Santa Cruz is experiencing the painfully slow process other cities should expect. Over 325,000 square feet of office and commercial space on Pacific Avenue was destroyed by the earthquake. About 200 businesses and 1,400 employees were displaced, and 45 buildings were damaged or destroyed. Economic losses were estimated at $100 million. Only within the last couple of months—more than three years after the quake—has the city completed the reconstruction of the utilities and the infrastructure. Now building owners must find businesses that can increase the commercial income by about 35 percent to pay for the repairs.

  • CALTRANS is a large and capable organization with strong leadership and resources and clear policy direction to repair and rebuild damaged structures and to retrofit existing structures statewide. Three years after the earthquake, damaged freeway structures are still being demolished. Repairs take time, especially if there are unique or unusual structural and geotechnical conditions. Repairs and retrofit costing $100 million for the 1.6-mile double-deck I-280 viaduct linking the South of Market area to Highway 101 will not be completed until mid-1994. The $700 million I-880 project to replace the Cypress viaduct will not be complete until late 1997.

  • In Oakland, 32 major buildings were damaged. Three years later, 16 still await repair or demolition. In some cases, owners can't pay for repairs or demolition, and the city is reluctant to pay, since the cost could exceed the value of the property. Oakland lost about 1,500 dwelling units for people with low incomes. Two years later, only 84 had been replaced.

Recovery is expensive for all parties. Federal disaster aid pays for only a small portion of the recovery, usually less than half. The various estimates of the

Suggested Citation:"1. Legacy of the Loma Prieta Earthquake: Challenges to Other Communities." National Research Council. 1994. Practical Lessons from the Loma Prieta Earthquake. Washington, DC: The National Academies Press. doi: 10.17226/2269.
×

damage and other losses from the Loma Prieta earthquake seem to be about $10 billion. The federal contribution through a variety of programs will amount to a bit over $2.5 billion, or about 25 percent of the total.

  • The state of California imposed a 1/4-cent sales tax increase for 13 months to raise about $800 million. Insurance payments totaled about $1 billion. The remainder of the losses must be paid by local governments, businesses, and private individuals.

  • Santa Cruz County recognized the need for additional funds and created a 1/4 percent increase in sales tax for six years. San Francisco and Oakland passed general obligation bond measures in part to finance repairs to damaged municipal buildings.

Recovery takes a long time, and it is expensive. Local government must hire the people and develop the skills to guide it through the process. Communities should anticipate the financial burden of disaster recovery and identify strategies to pay their share, even in lean times.

IF YOU CAN'T DO IT RIGHT, DON'T DO IT

The last three and one half years have demonstrated the difficulty inherent in implementing new knowledge and new programs. It is easy to say, "If we just applied what we now know, we could save money, buildings, and lives." But it is not easy to do.

Our professions are relatively knowledge-rich, but expertise-poor. A large segment of the professionals licensed to design our most significant buildings and infrastructure cannot competently apply the latest seismic design techniques. Yet these design and earth science professionals are responsible—and will be held accountable—for the vast majority of work that will either increase seismic risk if done wrong or decrease it if done right. Training pays off over time and can be accomplished without great cost.

In government, especially in California, it is difficult to hire and retain persons with seismic expertise. Multi-million dollar programs must be carried out using available staff, who generally lack specialized seismic expertise. Even though these people are intelligent, hard-working, and well-intended, they are invariably given significant responsibilities and tight schedules. They have precious little time and often no funds for professional training.

Contracting procedures, intended to provide qualified parties a fair chance at government contracts, make it difficult to distinguish among "licensed professionals." Laws now require that the cost of proposals and compliance with numerous quotas be given as much or more weight than demonstrated competence. Nontechnical managers who are responsible for personnel and contract decisions must rely on licensing laws for evidence of competence and on building codes for standards.

Suggested Citation:"1. Legacy of the Loma Prieta Earthquake: Challenges to Other Communities." National Research Council. 1994. Practical Lessons from the Loma Prieta Earthquake. Washington, DC: The National Academies Press. doi: 10.17226/2269.
×

Expertise is critical to performance. The Loma Prieta earthquake caused much damage that could have been prevented. With more attention to detail, many of the monetary and function losses could be stemmed. Simple things could be applied, such as bracing shelves, ceiling systems, lights, and sprinklers. Owners need to know that if they don't insist on hiring people with demonstrated competence and if they don't insist on attention to detail and quality in construction, they are not likely to get it.

Code enforcement is critical to performance. The vast majority of our building stock is not "engineered." Because of the lack of professional expertise and the large number of buildings built without design professional involvement, we have a system that relies heavily on building codes and code enforcement to protect the public safety. Having building codes and enforcing them are two very different matters.

Public school buildings are one class of buildings that performed well, even those buildings built to older codes, which are now considered inadequate. Their performance showed that plan checking by experienced structural engineers and thorough, full-time inspection are more important than the codes themselves. Improving code enforcement by requiring rigorous plan checking, using expert review panels on significant buildings and structures and requiring thorough, "special" inspection, are proven techniques to reduce seismic risk and protect valuable capital investments.

You are the leaders of the professions responsible for seismic safety, but the overwhelming bulk of the work across the state and nation is done by others. These people are not here today. Most of our colleagues will never develop the needed expertise. Improving the knowledge of our practicing design and earth science professionals, code enforcement officials, and building contractors must be accorded the highest priority. To further reduce our risk, we need:

  • to insist on professional training in seismic principles;

  • to test for seismic knowledge in license exams;

  • to consider seismic competence when selecting professionals and contractors; and

  • to insist on meaningful code enforcement.

These recommendations can put our knowledge to work at relatively low cost, but they will go nowhere without your advocacy before boards of registration, in your professional societies, and before city councils and state legislatures.

THE ABILITY TO PREDICT DAMAGE

Before closing I want to continue with my theme of using knowledge to reduce risk through public advocacy by using one more example. In the months following the Loma Prieta earthquake, I listened to elected officials, news re-

Suggested Citation:"1. Legacy of the Loma Prieta Earthquake: Challenges to Other Communities." National Research Council. 1994. Practical Lessons from the Loma Prieta Earthquake. Washington, DC: The National Academies Press. doi: 10.17226/2269.
×

porters, and other individuals criticize our statements that we could have foretold much of the damage. One member of the state Assembly stated during a hearing regarding funds to study the aftermath of the Loma Prieta earthquake: "You guys already know what's going to happen. You were right. Why do you want to study it? Just do something about it!" He voted "no."

After the Loma Prieta earthquake, I responded to questions from the press by saying it was common knowledge that the Marina District was prone to liquefaction; it was common knowledge that unreinforced masonry buildings were vulnerable to life-threatening damage; and, yes, it was common knowledge that older concrete structures were likely to lack the steel reinforcement and connection details needed to resist strong ground shaking. Virtually everyone in this room either did or could have answered in the same way. The press and the public were not impressed with our knowledge. They were shocked that we knew so much and did so little.

Because we already know or can readily find out where damage is likely, we must put this knowledge to work. Only by identifying vulnerable buildings and retrofitting them to appropriate standards can we prevent unnecessary losses and protect the buildings and functions we hold important. We must do a better job convincing policy makers to use our knowledge.

CONCLUSION

You are the elite from each of your professions. Your mere presence here tells me that you are motivated to learn and to apply what you know to your practice. Unfortunately, when Lloyd Cluff completes his closing remarks tomorrow afternoon, the knowledge gap between you and the tens of thousands of practitioners from all of our disciplines will be greater than ever. The gap between knowledge and public policy will be wider.

We need a new resolve to close these gaps in a systematic way. The successes and failures since Loma Prieta point to the absence of such a program, which is the foremost and most worrisome legacy of the earthquake.

Consider the points I have made:

  • There is a growing gap between what is known and what is used and between the expert and the practitioner.

  • Narrowing these gaps by enacting new policy depends on you; no one else is more knowledgeable or committed to the effort.

  • NEHRP should be changed to emphasize implementation, incentives, and actions that reduce and manage risk.

  • Disaster aid programs and our responses to damage need to accommodate irreversible changes and provide flexibility.

You and I must participate in advocacy. Each of us should ask whether our knowledge is being used. Ask how each new lesson can be used to lower seis-

Suggested Citation:"1. Legacy of the Loma Prieta Earthquake: Challenges to Other Communities." National Research Council. 1994. Practical Lessons from the Loma Prieta Earthquake. Washington, DC: The National Academies Press. doi: 10.17226/2269.
×

mic risk to life and the economy. Consider whether there is a policy mechanism to assure that the lessons will be applied by the majority of the professionals in your field. Consider the steps you can take to make a difference.

We all share a common need to improve earthquake risk reduction and management efforts. But the Loma Prieta earthquake and three and one half years of recovery have taught us that it will not be an easy task to accomplish this goal. We must change our strategy from sole emphasis on the development of knowledge, to one of integrating seismic risk concerns and knowledge into the mainstream activities of both government and business. We will succeed only when we contribute more knowledge to these activities and when we take advantage of the factors that motivate government and business. We will succeed only when seismic programs are no longer seen as separate programs and when you and I transfer and integrate our knowledge into mainstream private-and public-sector activities.

This is the legacy of the Loma Prieta earthquake. This is our charge.

Suggested Citation:"1. Legacy of the Loma Prieta Earthquake: Challenges to Other Communities." National Research Council. 1994. Practical Lessons from the Loma Prieta Earthquake. Washington, DC: The National Academies Press. doi: 10.17226/2269.
×
Page 19
Suggested Citation:"1. Legacy of the Loma Prieta Earthquake: Challenges to Other Communities." National Research Council. 1994. Practical Lessons from the Loma Prieta Earthquake. Washington, DC: The National Academies Press. doi: 10.17226/2269.
×
Page 20
Suggested Citation:"1. Legacy of the Loma Prieta Earthquake: Challenges to Other Communities." National Research Council. 1994. Practical Lessons from the Loma Prieta Earthquake. Washington, DC: The National Academies Press. doi: 10.17226/2269.
×
Page 21
Suggested Citation:"1. Legacy of the Loma Prieta Earthquake: Challenges to Other Communities." National Research Council. 1994. Practical Lessons from the Loma Prieta Earthquake. Washington, DC: The National Academies Press. doi: 10.17226/2269.
×
Page 22
Suggested Citation:"1. Legacy of the Loma Prieta Earthquake: Challenges to Other Communities." National Research Council. 1994. Practical Lessons from the Loma Prieta Earthquake. Washington, DC: The National Academies Press. doi: 10.17226/2269.
×
Page 23
Suggested Citation:"1. Legacy of the Loma Prieta Earthquake: Challenges to Other Communities." National Research Council. 1994. Practical Lessons from the Loma Prieta Earthquake. Washington, DC: The National Academies Press. doi: 10.17226/2269.
×
Page 24
Suggested Citation:"1. Legacy of the Loma Prieta Earthquake: Challenges to Other Communities." National Research Council. 1994. Practical Lessons from the Loma Prieta Earthquake. Washington, DC: The National Academies Press. doi: 10.17226/2269.
×
Page 25
Suggested Citation:"1. Legacy of the Loma Prieta Earthquake: Challenges to Other Communities." National Research Council. 1994. Practical Lessons from the Loma Prieta Earthquake. Washington, DC: The National Academies Press. doi: 10.17226/2269.
×
Page 26
Suggested Citation:"1. Legacy of the Loma Prieta Earthquake: Challenges to Other Communities." National Research Council. 1994. Practical Lessons from the Loma Prieta Earthquake. Washington, DC: The National Academies Press. doi: 10.17226/2269.
×
Page 27
Suggested Citation:"1. Legacy of the Loma Prieta Earthquake: Challenges to Other Communities." National Research Council. 1994. Practical Lessons from the Loma Prieta Earthquake. Washington, DC: The National Academies Press. doi: 10.17226/2269.
×
Page 28
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The Loma Prieta earthquake struck the San Francisco area on October 17, 1989, causing 63 deaths and $10 billion worth of damage. This book reviews existing research on the Loma Prieta quake and draws from it practical lessons that could be applied to other earthquake-prone areas of the country. The volume contains seven keynote papers presented at a symposium on the earthquake and includes an overview written by the committee offering recommendations to improve seismic safety and earthquake awareness in parts of the country susceptible to earthquakes.

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