EARTHQUAKES: LESSONS FROM THE PAST, PART 1

One of the most important lessons from recent earthquakes in Taiwan (September 1999), Athens (September 1999), and Turkey (August 1999) is this: No single government has all the answers or all the resources to manage the worst earthquake disasters likely to strike in the future. Based on the damage sustained in these three earthquakes, as well as those in Kobe (1995), Armenia (1988), and other seismic hot spots, Southern Californians and others living in quake-prone regions should be prepared for something exceptionally horrific, including life loss that may greatly exceed any previous U.S. disaster.

Every damaging earthquake is a sort of library, a storehouse of lessons for those in search of them. The problem is quantifying these lessons in a meaningful way, then determining how society should weave them into the fabric of modern daily life, commerce, and governance in a manner that will prevent the unnecessary loss of lives and property in future seismic events.

It’s a sad reality that many lessons from contemporary quakes are actually a rehash of those that should have been gleaned from past events. The continuing conflict between embracing and ignoring information from damaging earthquakes is an indication that modern society hasn’t fully developed the ability to absorb the most important elements of these lessons.

The United States rode a figurative wave of seismic good luck through the 20th century. Despite a series of moderate quakes that caused serious damage and more than 100 fatalities and a Great Quake that killed hundreds (some experts say thousands) in San Francisco in 1906, the United States has yet to suffer a catastrophe on the scale of the recent earthquakes in Turkey and Taiwan, where tens of thousands died in collapsing buildings.

The 7.1 Hector Mine earthquake that struck Southern California on October 16, 1999, was indicative of the frail balance between good and bad seismic fortune in the United States. The quake originated on a fault once thought to be inactive, tearing through 25 miles of desert floor near Twenty Nine Palms, 100 miles east of Los Angeles, displacing the ground by nearly 15 feet. If a rupture on that scale had occurred beneath virtually any heavily populated spot in the Greater Los Angeles Area, firefighters and urban search and rescue (USAR) teams might have been struggling to locate and extract live victims from the rubble of collapsed buildings two weeks later. But this was a sparsely populated desert, and not a single person died.

Recently, it was announced that a new blind thrust fault capable of a 7.3 earthquake has been discovered in Southern California’s Orange County. It is one of many newly recognized earthquake faults capable of causing catastrophe.

Such discoveries should serve as reminders to intensify preparations for the major seismic events likely to strike the United States during the next century, including the potential for one or more truly large quakes that could cause devastation across thousands of square miles in places like California, Alaska, Washington State, and the New Madrid Fault Zone.

The most recent quakes in Turkey caused several coastal towns to literally sink beneath the sea. The tsunamis that followed flooded several coastal zones. Similar effects are expected along the West Coast of the United States. The shaking collapsed thousands of buildings, killing at least 15,000 people. Two weeks later, across the Aegean Sea, Athens, Greece, was pounded by a quake that collapsed dozens of modern buildings. In Asia, entire cities have been leveled by quakes that killed untold numbers of people, the latest of which struck Taiwan. Modern Asian cities have been severely damaged by tremors whose ferocity architects and builders never anticipated. Similar conditions are found in places like Los Angeles, San Bernadino, San Francisco, and Seattle.

When I was dispatched as part of a team to observe Japanese emergency operations following the Kobe earthquake, the ease with which the shaking toppled and crushed modern “Western-style” steel and concrete buildings left a vivid impression. Another shock was witnessing the devastating effect of firestorms that swept large swaths of the city and burned people alive as they lay trapped in collapsed buildings.

POTENTIAL IMPENDING DISASTERS?

The potential for seismic disaster is seen wherever the earth moves with regularity. In Chile and Mexico, great quake-spawned tsunamis swept entire coastal areas clean of human habitation in 1996. In Mexico City, which lost more than 10,000 residents to a 1985 quake, millions of people live in structures built on an ancient lake bed that sometimes accentuates the ground motion of earthquakes. In terms of seismic risk, it is a city built for disaster.

During the 1800s, the flow of the Mississippi River was for a time reversed by a series of earthquakes in the New Madrid Fault Zone-quakes of a size and ferocity that seldom have been witnessed. In those days the fault zone was sparsely populated, so the human effect was not particularly evident. But today, this region is densely clustered with apartments, high-rises, industrial complexes, and chemical factories erected by designers who apparently forgot or ignored the lessons of the New Madrid earthquakes. A similar event today would cause a catastrophe unprecedented in U.S. history.

In Los Angeles, the 1994 Northridge quake struck on a blind thrust fault that wasn’t even known to seismologists. The eastern end of the Santa Susana Mountains grew more than a foot in a matter of seconds and rose several more inches during ensuing aftershocks. The thrusting fault alternately raised and lowered large chunks of the San Fernando Valley, permanently changing the elevation of many neighborhoods by as much as nine inches.

The landmark Palos Verdes peninsula in Southern California is actually a fold of the ocean floor; it grows ever higher as the crust is compressed several inches every year by the collision of the Pacific and North American plates. Twenty-six miles offshore from Los Angeles, Catalina Island and her offshore sisters are a product of great tectonic forces. Just to the east of Los Angeles, the towering San Gabriel Mountains owe their steep ascent to a locked “dog leg” section of the San Andreas Fault, which pushes the mountains upward much like one might squeeze folds of skin together on the back of one’s hand. The 10,000-foot-high San Gabriels are growing faster than erosion can wear them down. Similar dynamics are in evidence across Southern California.

In some ways, the Greater Los Angeles area is one giant tectonic laboratory, where all possible effects of earthquakes-and man’s societal response (including emergency services)-are tested in real time.

SEARCH AND RESCUE OPERATIONS

The average person-and even some emergency responders-might assume that no one can survive in large buildings that have collapsed into piles of rubble after an earthquake. The subsequent rescue of trapped victims after the first day is almost universally a surprise and is characterized as “miraculous” by the media, politicians, and the public. Consequently, search and rescue operations often taper off after the first day. People simply don’t expect survivors after Day 1. Yet, many collapsed buildings (the collapse might be caused by any phenomenon, not just earthquakes) are honeycombed with void spaces in which victims might be trapped alive. There is indisputable evidence to support this view.

In Mexico City, many people-including infants in a collapsed hospital-were rescued alive after more than a week of entrapment. Following the Armenia quake, survivors were rescued after nine days. In the Philippines quake, a man was extracted by the Dade County (FL) and Fairfax County (VA) Fire/Rescue USAR Task Forces following 13 days of entrapment in a collapsed hotel; he had a broken ankle and was dehydrated. A man, Buck Helm, was pulled from the collapsed Nimitz Freeway by California rescuers four days after the 1989 Loma Prieta earthquake. (He subsequently died in the hospital from complications of crush syndrome, a common entrapment-related malady that may be effectively treated by paramedics and physicians during and after the extrication process-an important lesson for fire/rescue and medical professionals faced with long-term entrapment of victims in collapsed buildings.)

This knowledge, combined with experience gleaned from other earthquakes and collapse incidents, accounted for the decision to conduct round-the-clock search and rescue operations for nearly 16 days following the 1995 bombing of the Alfred P. Murrah Building in Oklahoma City and will have a profound effect on long-term search and rescue operations following major earthquakes in the coming century.

The Criticality of Experience and Training

After the Murrah Building was bombed, the Federal Emergency Management Agency (FEMA) dispatched to Oklahoma City members of several quake-seasoned USAR task forces by military transport planes. The quake-related experiences of these rescuers (as well as those of New York Task Force 1 at the World Trade Center bombing) told them that somewhere in the three-story mound of debris that encompassed the collapse of the nine-floor Murrah Federal Building, there was a chance that people might still be alive within survivable void spaces in sections of the building shielded from the blast wave. As it happened, no survivors were found after the first 24 hours, although search and rescue operations continued nonstop until nearly the entire collapse area was cleared of debris in one of the most complicated and dangerous rescue operations in U.S. history.

In retrospect, the absence of survivors after Day 1 of the Oklahoma City bombing was mainly a function of the damaging physiological effects of the blast wave, as well as the particular way in which the Murrah Building collapsed in pancake fashion after its support systems had been blown away and gravity took over. The low survivability of trapped victims following Day 1 should lead no one to conclude that search and rescue operations of future bombing- or earthquake-induced structural collapses would be futile after the first day. To the contrary, experienced rescuers understand that long-term survival of trapped victims should be expected until determined otherwise by physical or visual examination of all potential survivable void spaces.

The level of experience needed to properly evaluate rescue opportunities and conduct effective search and rescue in collapse disasters is a rare commodity. Fire department collapse rescue training courses, as well as classes taught to FEMA USAR Task Forces, provide the basis for this expertise. The United States, where seminal earthquake response training originated during the 1970s and the 1980s, is host to one of the most comprehensive systems of earthquake-related emergency training in the world. But as good as this training is for laying the groundwork for the nation’s firefighters and rescuers, nothing beats hands-on experience conducting emergency operations in actual collapse disasters ranging from earthquakes to explosions.

Because collapse disasters are relatively rare, most firefighters gain hands-on experience only if they live or work in disaster-prone areas. Notable exceptions are FEMA USAR Task Forces, which may be dispatched to disasters anywhere in the United States; USAR teams sponsored by the State Department’s Office of Foreign Disaster Assistance (part of the Agency for International Development); and similar teams sponsored by nations such as Israel, Switzerland, and Japan.

Consequently, teams of highly experienced rescuers are often scarce at earthquake disasters around the world, and locals are often left to their own devices, which may not include tools and methods designed to locate victims, stabilize structures, do tunneling, and lift heavy materials from collapsed buildings. In many cases, these countries’ emergency responders lack the experience to recognize that many people may be trapped alive within piles of rubble and inside badly damaged buildings. As a result, untold numbers of trapped victims have been abandoned for dead when officials prematurely declared an end to the search and rescue phase and the beginning of the so-called recovery phase-often shorthand for “we are going to begin bulldozing buildings with heavy equipment with little regard for the potential of survivors trapped within them.” This mindset should pose concern for residents of quake-prone regions, especially if local emergency officials share the same belief. Human survival times of one to two weeks (and sometimes beyond) should be the expected result of damaging quakes.

Long-term survival in an earthquake-induced building collapse should be recognized as a function of (1) the severity of ground shaking; (2) the quality of structural engineering and construction practices and materials; (3) the “destructive physics” that causes the failure of structural elements and systems; (4) the effect of gravity, which pulls all buildings back toward earth; (5) human physiology and the body’s response to injuries inflicted by the collapse; and (6) the will to live. To this list, many would add the effect of the individual’s personal faith. In earthquake disasters, these factors routinely combine in ways that permit humans to live for many days trapped in survivable void spaces.

Planning for Sustained Search and Rescue Operations

In the wake of the August 1999 Turkey earthquake, it was reported that some search and rescue teams began packing up to leave after just a few days. Many experienced fire and rescue professionals were puzzled by these reports, especially considering the tremendously high number of people who were missing and presumed trapped in collapsed structures across Turkey. Here is reinforcement of a lesson learned long ago by many fire and rescue professionals from Southern California: Emergency officials should be planning to pull live victims from the rubble for up to three weeks after catastrophic earthquakes, and they should be prepared to sustain nonstop search and rescue operations until all hope of locating viable victims has passed. The public has the right to expect this level of response to devastating quakes in the United States.

Once the victims who are obviously visible, lightly trapped, and readily reachable are rescued, resist the temptation to declare the start of the recovery phase until potential survivable void spaces have been searched for live victims. This is accomplished through two standard USAR processes known as void space search and selective debris removal.

During the void space search phase, well-trained and equipped firefighters and USAR task forces tunnel their way through the building using special tools, rope rescue, mining and tunneling, and structural stabilization methods. They use fiber-optic and ground-penetrating radar technology, special search cameras, extremely sensitive acoustic- and vibration-sensing instruments, search dogs, and direct visual and voice contact to locate victims trapped within void spaces created when the structure collapsed. In many cases, firefighters and other rescuers must squeeze through cracks and void spaces and crawl through the interior of collapsed buildings to positively determine whether victims are trapped. This work is extremely hazardous, but it is essential. This was the method used to locate many victims within the collapsed Northridge Meadows apartments on January 17, 1994.

After all known survivable void spaces are searched, selective debris removal begins. Firefighters and USAR task forces work closely with heavy equipment operators, structural engineers, construction and demolition contractors, and others to take the building apart piece by piece, usually from top to bottom. As the building’s upper layers are selectively peeled away like an onion, newly accessible parts of the building are checked for potential survivors.

Alternating void space searches with selective debris removal should generally continue until all void spaces have been checked, the entire building has been dismantled, or all possible survivors have been located and extracted. These operations are extremely dangerous because of the instability of damaged buildings, as well as the continuing aftershocks that accompany major earthquakes. Without proper training, equipment, and experience, personnel conducting these operations can cause the building to collapse, killing rescuers and victims alike.

During these stages of a disaster, some of the most difficult, complex, and time-consuming rescues are made. These operations are the “bread and butter” operations of modern USAR-ready fire departments, as well as FEMA’s 27 USAR Task Forces. They are also a mainstay of many internationally deployed USAR teams. Until these phases of rescue have been completed, officials should refrain from declaring that the “recovery phase” has begun.

In the Taiwan disaster, two pet dogs were found alive in the rubble of their collapsed apartment building 18 days after the earthquake struck. Apparently, the dogs were trapped beneath furniture that created a survivable void space and prevented the ceiling from completely flattening the apartment. They survived by drinking water from an aquarium and eating thawing meat from a freezer ripped open by the collapse. If two dogs can survive 18 days trapped in a collapsed building, couldn’t humans do the same under favorable conditions?

When dealing with serious trauma, the Golden Hour is often emphasized-the optimum survival time within which firefighters and paramedics attempt to deliver injured victims to the definitive care of trauma centers and hospitals, often by helicopter. In recent years, another critical trauma benchmark, sometimes referred to as the “Golden First Day” of structure collapse, has become prevalent-a reference to the fact that the survival rate of trapped people begins to drop off after the first day. But, given what is known today, no one should automatically assume that the situation is a lost cause after the first day. Victims missing within collapsed buildings should not be written off simply because 24 hours have slipped by. Based on the current data, it is clear that search and rescue operations should be scaled back only after all potential survivable void spaces have been inspected, even if it takes two or three weeks.

Disastrous earthquakes around the world have been notorious for disorganized emergency response, disrupted communications, a lack of appropriate tools, inexperienced rescuers, stifled decision making, and the misinformed or misdirected judgment of some officials who took it upon themselves to terminate search and rescue operations prematurely to start “recovery operations” while live victims await assistance in vain within the rubble of collapsed buildings.

In some cases search and rescue efforts were called off when it became embarrassingly obvious that the local jurisdiction or country had to rely on outside search and rescue assistance, and when certain political leaders-or their constituents-viewed the acceptance of outside help as a sign of weakness in their own systems.

APPLYING LESSONS IN THE UNITED STATES

Of course, it is the responsibility of U.S. fire and rescue professionals and public officials to ensure that such mistakes are not repeated. Fortunately, many earthquake-prone regions are blessed with public officials who support fire and rescue efforts during times of disaster, and who do not consider using outside assistance as a sign of weakness. They realize that mutual aid makes sense to ensure the most effective life- and property-saving service during widespread emergencies and that disaster search and rescue operations may be lengthy. n

Mid-Rise Collapse

Floor 2 of the five-story Kaiser PermAnente medical office building collapsed pancake-style during the 1994 Northridge earthquake. The shaking caused the collapse of all five floors on either end of the building, eliminating two forms of ingress/ egress-the stairwells at each end of the structure. Los Angeles Fire Department units discovered the collapse while conducting mandatory “window” jurisdictional damage surveys immediately following the quake. It was also noted from the air by a Los Angeles County Fire Department Air Operations helicopter conducting aerial damage surveys of the northern San Fernando Valley. The helicopter landed in the parking lot and determined that the medical offices had been unoccupied because of the early morning hour of the quake.

Despite the obvious devastation to Floor 2, it was honeycombed with survivable void spaces between office furniture and other debris within the pancake collapse. In addition, survivable void spaces were in the collapse zones at each end of the building. It’s evident that if the quake had occurred later in the day-when hundreds of workers and patients would have occupied the building-complex, time-consuming, and highly dangerous search and rescue operations would have been required. It’s likely that at least one FEMA US&R Task Force would have been needed to completely search for and rescue victims trapped within.

A number of serious questions would have confronted the incident commander of such an operation, including the following:

  • What would be the best way to deal with the extreme collapse potential on Floor 1 and some of the upper floors, which had been damaged and would be subjected to strong aftershocks throughout Day 1?
  • How would search operations begin on Floor 2?-Would you enter from Floor 1 and move upward, possibly tunneling into the ceiling to reach Floor 2?-Would you enter from the roof and move downward?-Would you enter horizontally directly into Floor 2 by ladders, using shoring?-Would you enter horizontally into Floor 3 and tunnel down through the floor? What would be the best way to rescue victims trapped on Floor 2 and those trapped on the other floors at both ends of the building?-Would you use cranes and heavy equipment to “strip away” each of the top floors, like an onion, to remove the overhead weight and hazards to finally reach Floor 2?-Would it be possible to tunnel down into Floor 2 from Floor 3 to access and extract trapped victims?-Would it be possible to sufficiently stabilize Floor 1 to tunnel upward through the floor of Floor 2?-Would it be possible to tunnel horizontally from the exterior directly into Floor 2, relying on the existing debris and added shoring to keep the rest of the building off the rescuers?-What resources would be needed to conduct such operations in a reasonably safe and timely manner? What will be needed to address the potential for fires to occur during the search and rescue operations within the building?


Photo 1:Aerial surveys have proven critical to quickly identifying major fires, structural collapses, damaged dams, and other significant events that accompany major earthquakes. Shown is one of several potential conflagrations that spread across the northern San Fernando Valley during the Northridge earthquake. A mild Santa Ana wind helped push this fire through much of the trailer park before fire units, operating without hydrant water because local water mains were ruptured, could contain it.


Photo 2:A strike team of engines arrives at the entrance of the burning trailer park. The first-arriving units were attempting to contain the fire with water from their apparatus tanks. (Photos by Joe Moline, Los Angeles County Fire Department Air Operations.)


Photo 3:Post earthquake search and rescue operations often involve lifting and moving heavy objects. Diligent training reduces the hazards inherent in these tasks. Here, firefighters use air bags and cribbing to move a large concrete block across a training site. They must move slowly and in a controlled manner. Any unexpected movement can endanger rescuers and victims.


Photo 4:Some heavy objects must be broken down, tunneled beneath, or penetrated before trapped victims can be reached. Here, Los Angeles County Fire Department’s FEMA US&R Task Force (CATF-2) prepares to conduct search and recon operations during a training session at a demolished steel mill. Among considerations in such an operation are the following: How do you assess the stability of a large object before committing personnel into or beneath it, especially when aftershocks continue to rock the earth after a major earthquake? What type of shoring/stabilization measures and materials may be needed? What tools and resources will be needed to detect the presence and locations of trapped victims? How will simultaneous search and rescue operations within the same structure affect personnel and victim safety? (Photos by author.)


Photo 5:FEMA Urban Search and Rescue Task Force members from Riverside, California, practice tunneling into the remains of a previously demolished steel mill to find a mannequin that rescue instructors had placed within the bowels of the building.


Photo 6:Rescuers are mastering the techniques such as selective debris removal and void space search. (Photos by author.)


Photo 7:Firefighters/rescuers in earthquake-prone regions must be able to plan for emergency shoring and other stabilization measures. Are your personnel prepared to stabilize damaged buildings to support postearthquake search and rescue operations? Do they have quick access to the right tools and materials? Do they know where to obtain additional materials when supplies run out? Do they have access to the expertise of structural engineers who understand the fire department’s need to get inside the damaged building for search operations? If these local capabilities are absent, FEMA USAR Task Forces can be helpful. (Photo by author.)

Larry Collins is a fire captain, rescue specialist, paramedic and 20-year veteran of the County of Los Angeles Fire Department. He is currently assigned to Urban Search and Rescue Task Force 103, responsible for planning, instructing, supervising, and conducting technical rescue operations across the LACFD’s 2,278-mile jurisdiction. He is assigned as a search team manager of CATF-2, the LACFD’s Cal OES/FEMA US&R Task Force.

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