Why We Are In Trouble At The Sixth Seal (Revelation 6:12)

    

Why NRC Nuclear Safety Inspections are Necessary: Indian Point

Dave Lochbaum

This is the second in a series of commentaries about the vital role nuclear safety inspections conducted by the Nuclear Regulatory Commission (NRC) play in protecting the public. The initial commentary described how NRC inspectors discovered that limits on the maximum allowable control room air temperature at the Columbia Generating Station in Washington had been improperly relaxed by the plant’s owner. This commentary describes a more recent finding by NRC inspectors about animproper safety assessment of a leaking cooling water system pipe on Entergy’s Unit 3 reactor at Indian Point outside New York City.

Indian Point Unit 3: Leak Before Break

On February 3, 2017, the NRC issued Indian Point a Green finding for a violation of Appendix B to 10 CFR Part 50. Specifically, the owner failed to perform an adequate operability review per its procedures after workers discovered water leaking from a service water system pipe.

On April 27, 2016, workers found water leaking from the pipe downstream of the strainer for service water (SW) pump 31. As shown in Figure 1, SW pump 31 is one of six service water pumps located within the intake structure alongside the Hudson River. The six SW pumps are arranged in two sets of three pumps. Figure 1 shows SW pumps 31, 32, and 33 aligned to provide water drawn from the Hudson River to essential (i.e, safety and emergency) components within Unit 3. SW pumps 34, 35, and 36 are aligned to provide cooling water to non-essential equipment within Unit 3.

Fig. 1 (Source: Nuclear Regulatory Commission Plant Information Book) (click to enlarge)

Each SW pump is designed to deliver 6,000 gallons of flow. During normal operation, one SW pump can handle the essential loads while two SW pumps are needed for the non-essential loads. Under accident conditions, two SW pumps are needed to cool the essential equipment. The onsite emergency diesel generators can power either of the sets of three pumps, but not both simultaneously. If the set of SW pumps aligned to the essential equipment aren’t getting the job done, workers can open/close valves and electrical breakers to reconfigure the second set of three SW pumps to the essential equipment loops.

Because river water can have stuff in it that could clog some of the coolers for essential equipment, each SW pump has a strainer that attempts to remove as much debris as possible from the water. The leak discovered on April 27, 2016, was in the piping between the discharge check valve for SW pump 31 and its strainer. An arrow points to this piping section in Figure 1. The strainers were installed in openings called pits in the thick concrete floor of the intake structure. Water from the leaking pipe flowed into the pit housing the strainer for SW pump 31.

The initial leak rate was modest—estimated to be about one-eighth of a gallon per minute. The leak was similar to other pinhole leaks that had occurred in the concrete-lined, carbon steel SW pipes. The owner began daily checks on the leakage and prepared an operability determination. Basically, “operability determinations” are used within the nuclear industry when safety equipment is found to be impaired or degraded. The operability determination for the service water pipe leak concluded that the impairment did not prevent the SW pumps from fulfilling their required safety function. The operability determination relied on a sump pump located at the bottom of the strainer pit transferring the leaking water out of the pit before the water flooded and submerged safety components.

The daily checks instituted by the owner included workers recording the leak rate and assessing whether it had significantly increased. But the checks were against the previous day’s leak rate rather than the initial leak rate. By September 18, 2016, the leakage had steadily increased by a factor of 64 to 8 gallons per minute. But the daily incremental increases were small enough that they kept workers from finding the overall increase to be significant.

The daily check on October 15, 2016, found the pump room flooded to a depth of several inches. The leak rate was now estimated to be 20 gallons per minute. And the floor drain in the strainer pit was clogged (ironic, huh?) impairing the ability of its sump pump to remove the water. Workers placed temporary sump pumps in the room to remove the flood water and cope with the insignificantly higher leak rate. On October 17, workers installed a clamp on the pipe that reduced the leakage to less than one gallon per minute.

The operability determination was revised in response to concerns expressed by the NRC inspectors. The NRC inspectors were not satisfied by the revised operability determination. It continued to rely on the strainer pit sump pump removing the leaking water. But that sump pump was not powered from the emergency diesel generator and thus would not remove water should offsite power become unavailable. Step 5.6.4 of procedure EN-OP-14, “Operability Determination Process,” stated “If the Operability is based on the use or availability of other equipment, it must be verified that the equipment is capable of performing the function utilized in the evaluation.”

The operability determination explicitly stated that no compensatory measures or operator manual actions were needed to handle the leak, but the situation clearly required both compensatory measures and operator manual actions.

The NRC inspectors found additional deficiencies in the revised operability determination. The NRC inspectors calculated that a 20 gallon per minute leak rate coupled with an unavailable strainer pit sump pump would flood the room to a depth of three feet in three hours. There are no flood alarms in the room and the daily checks might not detect flooding until the level rose to three feet. At that level, water would submerge and potentially disable the vacuum breakers for the SW pumps. Proper vacuum breaker operation could be needed to successfully restart the SW pumps.

The NRC inspectors calculated that the 20 gallon per minute leak rate without remediation would flood the room to the level of the control cabinets for the strainers in 10 hours. The submerged control cabinets could disable the strainers, leading to blocked cooling water flow to essential equipment.

The NRC inspects calculated that the 20 gallon per minute leak rate without remediation would completely fill the room in about 29 hours, or only slightly longer than the daily check interval.

Flooding to depths of 3 feet, 10 feet, and the room’s ceiling affected all six SW pumps. Thus, the flooding represented a common mode threat that could disable the entire service water system. In turn, all safety equipment shown in Figure 2 no longer cooled by the disabled service water system could also be disabled. The NRC estimated that the flooding risk was about 5×10-6 per reactor year, solidly in the Green finding band.

Fig. 2 (Source: Nuclear Regulatory Commission Plant Information Book) (click to enlarge)

UCS Perspective

“Leak before break” is a longstanding nuclear safety philosophy. Books have been written about it (well, at least one report has been written and may even have been read.)  The NRC’s approval of a leak before break analysis can allow the owner of an existing nuclear power reactor to remove pipe whip restraints and jet impingement barriers. Such hardware guarded against the sudden rupture of a pipe filled with high pressure fluid from damaging safety equipment in the area. The leak before break analyses can provide the NRC with sufficient confidence that piping degradation will be detected by observed leakage with remedial actions taken before the pipe fails catastrophically. More than a decade ago, the NRC issued a Knowledge Management document on the leak before break philosophy and acceptable methods of analyzing, monitoring, and responding to piping degradation.

This incident at Indian Point illustrated an equally longstanding nuclear safety practice of “leak before break.” In this case, the leak was indeed followed by a break. But the break was not the failure of the piping but failure of the owner to comply with federal safety regulations. Pipe breaks are bad. Regulation breaks are bad. Deciding which is worse is like trying to decide which eye one wants to be poked in. None is far better than either.

As with the prior Columbia Generating Station case study, this Indian Point case study illustrates the vital role that NRC’s enforcement efforts plays in nuclear safety. Even after NRC inspectors voiced clear concerns about the improperly evaluated service water system pipe leak, Entergy failed to properly evaluate the situation, thus violating federal safety regulations. To be fair to Entergy, the company was probably doing its best, but in recent years, Entergy’s best has been far below nuclear industry average performance levels.

The NRC’s ROP is the public’s best protection against hazards caused by aging nuclear power reactors, shrinking maintenance budgets, emerging sabotage threats, and Entergy.Replacing the NRC’s engineering inspections with self-assessments by Entergy would lessen the effectiveness of that protective shield.

The NRC must continue to protect the public to the best of its ability. Delegating safety checks to owners like Entergy is inconsistent with that important mission.

Support from UCS members make work like this possible. Will you join us? Help UCS advance independent science for a healthy environment and a safer world.he Hudson River. The six SW pumps are arranged in two sets of three pumps. Figure 1 shows SW pumps 31, 32, and 33 aligned to provide water drawn from the Hudson River to essential (i.e, safety and emergency) components within Unit 3. SW pumps 34, 35, and 36 are aligned to provide cooling water to non-essential equipment within Unit 3. Fig. 1 (Source: Nuclear Regulatory Commission Plant Information Book) (click to enlarge) Each SW pump is designed to deliver 6,000 gallons of flow. During normal operation, one SW pump can handle the essential loads while two SW pumps are needed for the non-essential loads. Under accident conditions, two SW pumps are needed to cool the essential equipment. The onsite emergency diesel generators can power either of the sets of three pumps, but not both simultaneously. If the set of SW pumps aligned to the essential equipment aren’t getting the job done, workers can open/close valves and electrical breakers to reconfigure the second set of three SW pumps to the essential equipment loops. Because river water can have stuff in it that could clog some of the coolers for essential equipment, each SW pump has a strainer that attempts to remove as much debris as possible from the water. The leak discovered on April 27, 2016, was in the piping between the discharge check valve for SW pump 31 and its strainer. An arrow points to this piping section in Figure 1. The strainers were installed in openings called pits in the thick concrete floor of the intake structure. Water from the leaking pipe flowed into the pit housing the strainer for SW pump 31. The initial leak rate was modest—estimated to be about one-eighth of a gallon per minute. The leak was similar to other pinhole leaks that had occurred in the concrete-lined, carbon steel SW pipes. The owner began daily checks on the leakage and prepared an operability determination. Basically, “operability determinations” are used within the nuclear industry when safety equipment is found to be impaired or degraded. The operability determination for the service water pipe leak concluded that the impairment did not prevent the SW pumps from fulfilling their required safety function. The operability determination relied on a sump pump located at the bottom of the strainer pit transferring the leaking water out of the pit before the water flooded and submerged safety components. The daily checks instituted by the owner included workers recording the leak rate and assessing whether it had significantly increased. But the checks were against the previous day’s leak rate rather than the initial leak rate. By September 18, 2016, the leakage had steadily increased by a factor of 64 to 8 gallons per minute. But the daily incremental increases were small enough that they kept workers from finding the overall increase to be significant. The daily check on October 15, 2016, found the pump room flooded to a depth of several inches. The leak rate was now estimated to be 20 gallons per minute. And the floor drain in the strainer pit was clogged (ironic, huh?) impairing the ability of its sump pump to remove the water. Workers placed temporary sump pumps in the room to remove the flood water and cope with the insignificantly higher leak rate. On October 17, workers installed a clamp on the pipe that reduced the leakage to less than one gallon per minute. The operability determination was revised in response to concerns expressed by the NRC inspectors. The NRC inspectors were not satisfied by the revised operability determination. It continued to rely on the strainer pit sump pump removing the leaking water. But that sump pump was not powered from the emergency diesel generator and thus would not remove water should offsite power become unavailable. Step 5.6.4 of procedure EN-OP-14, “Operability Determination Process,” stated “If the Operability is based on the use or availability of other equipment, it must be verified that the equipment is capable of performing the function utilized in the evaluation.” The operability determination explicitly stated that no compensatory measures or operator manual actions were needed to handle the leak, but the situation clearly required both compensatory measures and operator manual actions. The NRC inspectors found additional deficiencies in the revised operability determination. The NRC inspectors calculated that a 20 gallon per minute leak rate coupled with an unavailable strainer pit sump pump would flood the room to a depth of three feet in three hours. There are no flood alarms in the room and the daily checks might not detect flooding until the level rose to three feet. At that level, water would submerge and potentially disable the vacuum breakers for the SW pumps. Proper vacuum breaker operation could be needed to successfully restart the SW pumps. The NRC inspectors calculated that the 20 gallon per minute leak rate without remediation would flood the room to the level of the control cabinets for the strainers in 10 hours. The submerged control cabinets could disable the strainers, leading to blocked cooling water flow to essential equipment. The NRC inspects calculated that the 20 gallon per minute leak rate without remediation would completely fill the room in about 29 hours, or only slightly longer than the daily check interval. Flooding to depths of 3 feet, 10 feet, and the room’s ceiling affected all six SW pumps. Thus, the flooding represented a common mode threat that could disable the entire service water system. In turn, all safety equipment shown in Figure 2 no longer cooled by the disabled service water system could also be disabled. The NRC estimated that the flooding risk was about 5×10-6 per reactor year, solidly in the Green finding band. Fig. 2 (Source: Nuclear Regulatory Commission Plant Information Book) (click to enlarge) UCS Perspective “Leak before break” is a longstanding nuclear safety philosophy. Books have been written about it (well, at least one report has been written and may even have been read.) The NRC’s approval of a leak before break analysis can allow the owner of an existing nuclear power reactor to remove pipe whip restraints and jet impingement barriers. Such hardware guarded against the sudden rupture of a pipe filled with high pressure fluid from damaging safety equipment in the area. The leak before break analyses can provide the NRC with sufficient confidence that piping degradation will be detected by observed leakage with remedial actions taken before the pipe fails catastrophically. More than a decade ago, the NRC issued a Knowledge Management document on the leak before break philosophy and acceptable methods of analyzing, monitoring, and responding to piping degradation. This incident at Indian Point illustrated an equally longstanding nuclear safety practice of “leak before break.” In this case, the leak was indeed followed by a break. But the break was not the failure of the piping but failure of the owner to comply with federal safety regulations. Pipe breaks are bad. Regulation breaks are bad. Deciding which is worse is like trying to decide which eye one wants to be poked in. None is far better than either. As with the prior Columbia Generating Station case study, this Indian Point case study illustrates the vital role that NRC’s enforcement efforts plays in nuclear safety. Even after NRC inspectors voiced clear concerns about the improperly evaluated service water system pipe leak, Entergy failed to properly evaluate the situation, thus violating federal safety regulations. To be fair to Entergy, the company was probably doing its best, but in recent years, Entergy’s best has been far below nuclear industry average performance levels. The NRC’s ROP is the public’s best protection against hazards caused by aging nuclear power reactors, shrinking maintenance budgets, emerging sabotage threats, and Entergy.Replacing the NRC’s engineering inspections with self-assessments by Entergy would lessen the effectiveness of that protective shield. The NRC must continue to protect the public to the best of its ability. Delegating safety checks to owners like Entergy is inconsistent with that important mission. Support from UCS members make work like this possible. Will you join us? Help UCS advance independent science for a healthy environment and a safer world.

New York Subways at the Sixth Seal (Revelation 6)

                      How vulnerable are NYC’s underwater subway tunnels to flooding?

Ashley Fetters
New York City is full of peculiar phenomena—rickety fire escapes; 100-year-old subway tunnels; air conditioners propped perilously into window frames—that can strike fear into the heart of even the toughest city denizen. But should they? Every month, writer Ashley Fetters will be exploring—and debunking—these New York-specific fears, letting you know what you should actually worry about, and what anxieties you can simply let slip away.
The 25-minute subway commute from Crown Heights to the Financial District on the 2/3 line is, in my experience, a surprisingly peaceful start to the workday—save for one 3,100-foot stretch between the Clark Street and Wall Street stations, where for three minutes I sit wondering what the probability is that I will soon die a torturous, claustrophobic drowning death right here in this subway car.
The Clark Street Tunnel, opened in 1916, is one of approximately a dozen tunnels that escort MTA passengers from one borough to the next underwater—and just about all of them, with the exception of the 1989 addition of the 63rd Street F train tunnel, were constructed between 1900 and 1936.
Each day, thousands of New Yorkers venture across the East River and back again through these tubes buried deep in the riverbed, some of which are nearing or even past their 100th birthdays. Are they wrong to ponder their own mortality while picturing one of these watery catacombs suddenly springing a leak?
Mostly yes, they are, says Michael Horodniceanu, the former president of MTA Capital Construction and current principal of Urban Advisory Group. First, it’s important to remember that the subway tunnel is built under the riverbed, not just in the river—so what immediately surrounds the tunnel isn’t water but some 25 feet of soil. “There’s a lot of dirt on top of it,” Horodniceanu says. “It’s well into the bed of the bottom of the channel.”
And second, as Angus Kress Gillespie, author of Crossing Under the Hudson: The Story of the Holland and Lincoln Tunnels, points out, New York’s underwater subway tunnels are designed to withstand some leaking. And withstand it they do: Pumps placed below the floor of the tunnel, he says, are always running, always diverting water seepage into the sewers. (Horodniceanu says the amount of water these pumps divert into the sewer system each day numbers in the thousands of gallons.)
Additionally, MTA crews routinely repair the grouting and caulking, and often inject a substance into the walls that creates a waterproof membrane outside the tunnel—which keeps water out of the tunnel and relieves any water pressure acting on its walls. New tunnels, Horodniceanu points out, are even built with an outside waterproofing membrane that works like an umbrella: Water goes around it, it falls to the sides, and then it gets channeled into a pumping station and pumped out.
Of course, the classic New York nightmare scenario isn’t just a cute little trickle finding its way in. The anxiety daydream usually involves something sinister, or seismic. The good news, however, is that while an earthquake or explosion would indeed be bad for many reasons, it likely wouldn’t result in the frantic flooding horror scene that plays out in some commuters’ imaginations.
The Montague Tube, which sustained severe damage during Hurricane Sandy.
MTA New York City Transit / Marc A. Hermann
Horodniceanu assures me that tunnels built more recently are “built to withstand a seismic event.” The older tunnels, however—like, um, the Clark Street Tunnel—“were not seismically retrofitted, let me put it that way,” Horodniceanu says. “But the way they were built is in such a way that I do not believe an earthquake would affect them.” They aren’t deep enough in the ground, anyway, he says, to be too intensely affected by a seismic event. (The MTA did not respond to a request for comment.)
One of the only real threats to tunnel infrastructure, Horodniceanu adds, is extreme weather. Hurricane Sandy, for example, caused flooding in the tunnels, which “created problems with the infrastructure.” He continues, “The tunnels have to be rebuilt as a result of saltwater corroding the infrastructure.”
Still, he points out, hurricanes don’t exactly happen with no warning. So while Hurricane Sandy did cause major trauma to the tunnels, train traffic could be stopped with ample time to keep passengers out of harm’s way. In 2012, Governor Andrew Cuomo directed all the MTA’s mass transit services to shut down at 7 p.m. the night before Hurricane Sandy was expected to hit New York City.
And Gillespie, for his part, doubts even an explosion would result in sudden, dangerous flooding. A subway tunnel is not a closed system, he points out; it’s like a pipe that’s open at both ends. “The force of a blast would go forwards and backwards out the exit,” he says.
So the subway-train version of that terrifying Holland Tunnel flood scene in Sylvester Stallone’s Daylight is … unrealistic, right?
“Yeah,” Gillespie laughs. “Yeah. It is.”
Got a weird New York anxiety that you want explored? E-mail tips@curbed.com, and we may include it in a future column.

The Sixth Seal Long Overdue (Revelation 6)

   

     

ON THE MAP; Exploring the Fault Where the Next Big One May Be Waiting

The Big One Awaits

By MARGO NASH

Published: March 25, 2001

Alexander Gates, a geology professor at Rutgers-Newark, is co-author of “The Encyclopedia of Earthquakes and Volcanoes,“ which will be published by Facts on File in July. He has been leading a four-year effort to remap an area known as the Sloatsburg Quadrangle, a 5-by-7-mile tract near Mahwah that crosses into New York State. The Ramapo Fault, which runs through it, was responsible for a big earthquake in 1884, and Dr. Gates warns that a recurrence is overdue. He recently talked about his findings.

Q. What have you found?

A. We’re basically looking at a lot more rock, and we’re looking at the fracturing and jointing in the bedrock and putting it on the maps. Any break in the rock is a fracture. If it has movement, then it’s a fault. There are a lot of faults that are offshoots of the Ramapo. Basically when there are faults, it means you had an earthquake that made it. So there was a lot of earthquake activity to produce these features. We are basically not in a period of earthquake activity along the Ramapo Fault now, but we can see that about six or seven times in history, about 250 million years ago, it had major earthquake activity. And because it’s such a fundamental zone of weakness, anytime anything happens, the Ramapo Fault goes.

Q. Where is the Ramapo Fault?

 A. The fault line is in western New Jersey and goes through a good chunk of the state, all the way down to Flemington. It goes right along where they put in the new 287. It continues northeast across the Hudson River right under the Indian Point power plant up into Westchester County. There are a lot of earthquakes rumbling around it every year, but not a big one for a while.

Q. Did you find anything that surprised you?

A. I found a lot of faults, splays that offshoot from the Ramapo that go 5 to 10 miles away from the fault. I have looked at the Ramapo Fault in other places too. I have seen splays 5 to 10 miles up into the Hudson Highlands. And you can see them right along the roadsides on 287. There’s been a lot of damage to those rocks, and obviously it was produced by fault activities. All of these faults have earthquake potential.

Q. Describe the 1884 earthquake.

A. It was in the northern part of the state near the Sloatsburg area. They didn’t have precise ways of describing the location then. There was lots of damage. Chimneys toppled over. But in 1884, it was a farming community, and there were not many people to be injured. Nobody appears to have written an account of the numbers who were injured.

Q. What lessons we can learn from previous earthquakes?

A. In 1960, the city of Agadir in Morocco had a 6.2 earthquake that killed 12,000 people, a third of the population, and injured a third more. I think it was because the city was unprepared.There had been an earthquake in the area 200 years before. But people discounted the possibility of a recurrence. Here in New Jersey, we should not make the same mistake. We should not forget that we had a 5.4 earthquake 117 years ago. The recurrence interval for an earthquake of that magnitude is every 50 years, and we are overdue. The Agadir was a 6.2, and a 5.4 to a 6.2 isn’t that big a jump.

Q. What are the dangers of a quake that size?

A. When you’re in a flat area in a wooden house it’s obviously not as dangerous, although it could cut off a gas line that could explode. There’s a real problem with infrastructure that is crumbling, like the bridges with crumbling cement. There’s a real danger we could wind up with our water supplies and electricity cut off if a sizable earthquake goes off. The best thing is to have regular upkeep and keep up new building codes. The new buildings will be O.K. But there is a sense of complacency.

MARGO NASH

The Trend Leading to the Sixth Seal (Revelation 6:12)

        

SMALL EARTHQUAKE SHAKES PARTS OF NEW YORK STATE

HOPKINS

January 14, 2020

Are we seeing a trend? After two small earthquakes hit upstate New York on January 3 and January 7, a slightly larger one was felt near the New York-Canadian border early Monday morning. And while the quake actually happened in an entirely different country, the effects were felt far south into New York state, and the surrounding region.

The United States Geological Survey says the 3.3 magnitude quake hit several mikes south of the town of Ormstown, Quebec a little after 5:30 A.M. There are some slightly conflicting reports, as the Montreal Gazette reports that the quake was a 3.6 magnitude. Ormstown is located around 20 minutes north of the New York border.

The Times Union says the quake was felt as far south as the town of Ticonderoga in Essex County, and as far west as the city of Ogdensburg on the New York-Ontario border. The effects were also felt as far north as Montreal.

No damage was reported.

Yes, earthquakes do happen in the northeastern U.S and Canada occasionally. In December 2019, a 2.1 tremor was reported near Sodus Point, off the coast of Lake Ontario.

Some strike even closer to home. In April 2017, a 1.3 tremor occurred around two and half miles west of Pawling. In early 2016, an even smaller quake happened near Port Chester and Greenwich, CT. In the summer of 2019, a quake struck off the New Jersey coast.

The most well known fault line near our area is the Ramapo fault line. The 185 mile system of faults runs through parts of New York, New Jersey, and Pennsylvania, and has been known to spawn usually small earthquakes.

On August 23, 2011, a 5.8 quake, that was centered in Virginia, was felt all the way up the east coast. Several moderate (at least a 5 on the richter scale) quakes have occurred near New York City in 1737, 1783 and 1884.

Listen to Middays With Hopkins weekdays from 10AM to 2PM on 101.5 WPDH. Stream us live through the website, Alexa-enabled device, Google Home or the WPDH mobile app.

The History Of New York Earthquakes: Before The Sixth Seal (Revelation 6:12)

            

Historic Earthquakes
Near New York City, New York
1884 08 10 19:07 UTC
Magnitude 5.5The History Of New York Earthquakes: Before The Sixth Seal (Rev 6:12)
Intensity VII
USGS.gov
This severe earthquake affected an area roughly extending along the Atlantic Coast from southern Maine to central Virginia and westward to Cleveland, Ohio. Chimneys were knocked down and walls were cracked in several States, including Connecticut, New Jersey, New York, and Pennsylvania. Many towns from Hartford, Connecticut, to West Chester,Pennsylvania.
Property damage was severe at Amityville and Jamaica, New York, where several chimneys were “overturned” and large cracks formed in walls. Two chimneys were thrown down and bricks were shaken from other chimneys at Stratford (Fairfield County), Conn.; water in the Housatonic River was agitated violently. At Bloomfield, N.J., and Chester, Pa., several chimneys were downed and crockery was broken. Chimneys also were damaged at Mount Vernon, N.Y., and Allentown, Easton, and Philadelphia, Pa. Three shocks occurred, the second of which was most violent. This earthquake also was reported felt in Vermont, Virginia, and Washington, D.C. Several slight aftershocks were reported on August 11.
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Columbia University Warns Of Sixth Seal (Revelation 6:12)

          

Earthquakes May Endanger New York More Than Thought, Says Study
A study by a group of prominent seismologists suggests that a pattern of subtle but active faults makes the risk of earthquakes to the New York City area substantially greater than formerly believed. Among other things, they say that the controversial Indian Point nuclear power plants, 24 miles north of the city, sit astride the previously unidentified intersection of two active seismic zones. The paper appears in the current issue of the Bulletin of the Seismological Society of America.
Many faults and a few mostly modest quakes have long been known around New York City, but the research casts them in a new light. The scientists say the insight comes from sophisticated analysis of past quakes, plus 34 years of new data on tremors, most of them perceptible only by modern seismic instruments. The evidence charts unseen but potentially powerful structures whose layout and dynamics are only now coming clearer, say the scientists. All are based at Columbia University’s Lamont-Doherty Earth Observatory, which runs the network of seismometers that monitors most of the northeastern United States.
Lead author Lynn R. Sykes said the data show that large quakes are infrequent around New Yorkcompared to more active areas like California and Japan, but that the risk is high, because of the overwhelming concentration of people and infrastructure. “The research raises the perception both of how common these events are, and, specifically, where they may occur,” he said. “It’s an extremely populated area with very large assets.” Sykes, who has studied the region for four decades, is known for his early role in establishing the global theory of plate tectonics.
The authors compiled a catalog of all 383 known earthquakes from 1677 to 2007 in a 15,000-square-mile area around New York City. Coauthor John Armbruster estimated sizes and locations of dozens of events before 1930 by combing newspaper accounts and other records. The researchers say magnitude 5 quakes—strong enough to cause damage–occurred in 1737, 1783 and 1884. There was little settlement around to be hurt by the first two quakes, whose locations are vague due to a lack of good accounts; but the last, thought to be centered under the seabed somewhere between Brooklyn and Sandy Hook, toppled chimneys across the city and New Jersey, and panicked bathers at Coney Island. Based on this, the researchers say such quakes should be routinely expected, on average, about every 100 years. “Today, with so many more buildings and people, a magnitude 5 centered below the city would be extremely attention-getting,” said Armbruster. “We’d see billions in damage, with some brick buildings falling. People would probably be killed.”
Starting in the early 1970s Lamont began collecting data on quakes from dozens of newly deployed seismometers; these have revealed further potential, including distinct zones where earthquakes concentrate, and where larger ones could come. The Lamont network, now led by coauthor Won-Young Kim, has located hundreds of small events, including a magnitude 3 every few years, which can be felt by people at the surface, but is unlikely to cause damage. These small quakes tend to cluster along a series of small, old faults in harder rocks across the region. Many of the faults were discovered decades ago when subways, water tunnels and other excavations intersected them, but conventional wisdom said they were inactive remnants of continental collisions and rifting hundreds of millions of years ago. The results clearly show that they are active, and quite capable of generating damaging quakes, said Sykes.
One major previously known feature, the Ramapo Seismic Zone, runs from eastern Pennsylvania to the mid-Hudson Valley, passing within a mile or two northwest of Indian Point. The researchers found that this system is not so much a single fracture as a braid of smaller ones, where quakes emanate from a set of still ill-defined faults. East and south of the Ramapo zone—and possibly more significant in terms of hazard–is a set of nearly parallel northwest-southeast faults. These include Manhattan’s 125th Street fault, which seems to have generated two small 1981 quakes, and could have been the source of the big 1737 quake; the Dyckman Street fault, which carried a magnitude 2 in 1989; the Mosholu Parkway fault; and the Dobbs Ferry fault in suburban Westchester, which generated the largest recent shock, a surprising magnitude 4.1, in 1985. Fortunately, it did no damage. Given the pattern, Sykes says the big 1884 quake may have hit on a yet-undetected member of this parallel family further south.
The researchers say that frequent small quakes occur in predictable ratios to larger ones, and so can be used to project a rough time scale for damaging events. Based on the lengths of the faults, the detected tremors, and calculations of how stresses build in the crust, the researchers say that magnitude 6 quakes, or even 7—respectively 10 and 100 times bigger than magnitude 5–are quite possible on the active faults they describe. They calculate that magnitude 6 quakes take place in the area about every 670 years, and sevens, every 3,400 years. The corresponding probabilities of occurrence in any 50-year period would be 7% and 1.5%. After less specific hints of these possibilities appeared in previous research, a 2003 analysis by The New York City Area Consortium for Earthquake Loss Mitigation put the cost of quakes this size in the metro New York area at $39 billion to $197 billion. A separate 2001 analysis for northern New Jersey’s Bergen County estimates that a magnitude 7 would destroy 14,000 buildings and damage 180,000 in that area alone. The researchers point out that no one knows when the last such events occurred, and say no one can predict when they next might come.
“We need to step backward from the simple old model, where you worry about one large, obvious fault, like they do in California,” said coauthor Leonardo Seeber. “The problem here comes from many subtle faults. We now see there is earthquake activity on them. Each one is small, but when you add them up, they are probably more dangerous than we thought. We need to take a very close look.” Seeber says that because the faults are mostly invisible at the surface and move infrequently, a big quake could easily hit one not yet identified. “The probability is not zero, and the damage could be great,” he said. “It could be like something out of a Greek myth.”
The researchers found concrete evidence for one significant previously unknown structure: an active seismic zone running at least 25 miles from Stamford, Conn., to the Hudson Valley town of Peekskill, N.Y., where it passes less than a mile north of the Indian Point nuclear power plant. The Stamford-Peekskill line stands out sharply on the researchers’ earthquake map, with small events clustered along its length, and to its immediate southwest. Just to the north, there are no quakes, indicating that it represents some kind of underground boundary. It is parallel to the other faults beginning at 125th Street, so the researchers believe it is a fault in the same family. Like the others, they say it is probably capable of producing at least a magnitude 6 quake. Furthermore, a mile or so on, it intersects the Ramapo seismic zone.
Sykes said the existence of the Stamford-Peekskill line had been suggested before, because the Hudson takes a sudden unexplained bend just ot the north of Indian Point, and definite traces of an old fault can be along the north side of the bend. The seismic evidence confirms it, he said. “Indian Point is situated at the intersection of the two most striking linear features marking the seismicity and also in the midst of a large population that is at risk in case of an accident,” says the paper. “This is clearly one of the least favorable sites in our study area from an earthquake hazard and risk perspective.”
The findings comes at a time when Entergy, the owner of Indian Point, is trying to relicense the two operating plants for an additional 20 years—a move being fought by surrounding communities and the New York State Attorney General. Last fall the attorney general, alerted to the then-unpublished Lamont data, told a Nuclear Regulatory Commission panel in a filing: “New data developed in the last 20 years disclose a substantially higher likelihood of significant earthquake activity in the vicinity of [Indian Point] that could exceed the earthquake design for the facility.” The state alleges that Entergy has not presented new data on earthquakes past 1979. However, in a little-noticed decision this July 31, the panel rejected the argument on procedural grounds. A source at the attorney general’s office said the state is considering its options.
The characteristics of New York’s geology and human footprint may increase the problem. Unlike in California, many New York quakes occur near the surface—in the upper mile or so—and they occur not in the broken-up, more malleable formations common where quakes are frequent, but rather in the extremely hard, rigid rocks underlying Manhattan and much of the lower Hudson Valley. Such rocks can build large stresses, then suddenly and efficiently transmit energy over long distances. “It’s like putting a hard rock in a vise,” said Seeber. “Nothing happens for a while. Then it goes with a bang.” Earthquake-resistant building codes were not introduced to New York City until 1995, and are not in effect at all in many other communities. Sinuous skyscrapers and bridges might get by with minimal damage, said Sykes, but many older, unreinforced three- to six-story brick buildings could crumble.
Art Lerner-Lam, associate director of Lamont for seismology, geology and tectonophysics, pointed out that the region’s major highways including the New York State Thruway, commuter and long-distance rail lines, and the main gas, oil and power transmission lines all cross the parallel active faults, making them particularly vulnerable to being cut. Lerner-Lam, who was not involved in the research, said that the identification of the seismic line near Indian Point “is a major substantiation of a feature that bears on the long-term earthquake risk of the northeastern United States.” He called for policymakers to develop more information on the region’s vulnerability, to take a closer look at land use and development, and to make investments to strengthen critical infrastructure.
“This is a landmark study in many ways,” said Lerner-Lam. “It gives us the best possible evidence that we have an earthquake hazard here that should be a factor in any planning decision. It crystallizes the argument that this hazard is not random. There is a structure to the location and timing of the earthquakes. This enables us to contemplate risk in an entirely different way. And since we are able to do that, we should be required to do that.”
New York Earthquake Briefs and Quotes:
Existing U.S. Geological Survey seismic hazard maps show New York City as facing more hazard than many other eastern U.S. areas. Three areas are somewhat more active—northernmost New York State, New Hampshire and South Carolina—but they have much lower populations and fewer structures. The wider forces at work include pressure exerted from continuing expansion of the mid-Atlantic Ridge thousands of miles to the east; slow westward migration of the North American continent; and the area’s intricate labyrinth of old faults, sutures and zones of weakness caused by past collisions and rifting.
Due to New York’s past history, population density and fragile, interdependent infrastructure, a 2001 analysis by the Federal Emergency Management Agency ranks it the 11th most at-risk U.S. city for earthquake damage. Among those ahead: Los Angeles, San Francisco, Seattle and Portland. Behind: Salt Lake City, Sacramento, Anchorage.
New York’s first seismic station was set up at Fordham University in the 1920s. Lamont-Doherty Earth Observatory, in Palisades, N.Y., has operated stations since 1949, and now coordinates a network of about 40.
Dozens of small quakes have been felt in the New York area. A Jan. 17, 2001 magnitude 2.4, centered  in the Upper East Side—the first ever detected in Manhattan itself–may have originated on the 125th Street fault. Some people thought it was an explosion, but no one was harmed.
The most recent felt quake, a magnitude 2.1 on July 28, 2008, was centered near Milford, N.J. Houses shook and a woman at St. Edward’s Church said she felt the building rise up under her feet—but no damage was done.
Questions about the seismic safety of the Indian Point nuclear power plant, which lies amid a metropolitan area of more than 20 million people, were raised in previous scientific papers in 1978 and 1985.
Because the hard rocks under much of New York can build up a lot strain before breaking, researchers believe that modest faults as short as 1 to 10 kilometers can cause magnitude 5 or 6 quakes.
In general, magnitude 3 quakes occur about 10 times more often than magnitude fours; 100 times more than magnitude fives; and so on. This principle is called the Gutenberg-Richter relationship.

Preparing for the Sixth Seal (Revelation 6:12)

         

Scenario Earthquakes for Urban Areas Along the Atlantic Seaboard of the United States
NYCEM

The Sixth Seal: NY City Destroyed

If today a magnitude 6 earthquake were to occur centered on New York City, what would its effects be? Will the loss be 10 or 100 billion dollars? Will there be 10 or 10,000 fatalities? Will there be 1,000 or 100,000 homeless needing shelter? Can government function, provide assistance, and maintain order?

At this time, no satisfactory answers to these questions are available. A few years ago, rudimentary scenario studies were made for Boston and New York with limited scope and uncertain results. For most eastern cities, including Washington D.C., we know even less about the economic, societal and political impacts from significant earthquakes, whatever their rate of occurrence.

Why do we know so little about such vital public issues? Because the public has been lulled into believing that seriously damaging quakes are so unlikely in the east that in essence we do not need to consider them. We shall examine the validity of this widely held opinion.

Is the public’s earthquake awareness (or lack thereof) controlled by perceived low Seismicity, Seismic Hazard, or Seismic Risk? How do these three seismic features differ from, and relate to each other? In many portions of California, earthquake awareness is refreshed in a major way about once every decade (and in some places even more often) by virtually every person experiencing a damaging event. The occurrence of earthquakes of given magnitudes in time and space, not withstanding their effects, are the manifestations of seismicity. Ground shaking, faulting, landslides or soil liquefaction are the manifestations of seismic hazard. Damage to structures, and loss of life, limb, material assets, business and services are the manifestations of seismic risk. By sheer experience, California’s public understands fairly well these three interconnected manifestations of the earthquake phenomenon. This awareness is reflected in public policy, enforcement of seismic regulations, and preparedness in both the public and private sector. In the eastern U.S., the public and its decision makers generally do not understand them because of inexperience. Judging seismic risk by rates of seismicity alone (which are low in the east but high in the west) has undoubtedly contributed to the public’s tendency to belittle the seismic loss potential for eastern urban regions.

Let us compare two hypothetical locations, one in California and one in New York City. Assume the location in California does experience, on average, one M = 6 every 10 years, compared to New York once every 1,000 years. This implies a ratio of rates of seismicity of 100:1. Does that mean the ratio of expected losses (when annualized per year) is also 100:1? Most likely not. That ratio may be closer to 10:1, which seems to imply that taking our clues from seismicity alone may lead to an underestimation of the potential seismic risks in the east. Why should this be so?

To check the assertion, let us make a back-of-the-envelope estimate. The expected seismic risk for a given area is defined as the area-integrated product of: seismic hazard (expected shaking level), assets ($ and people), and the assets’ vulnerabilities (that is, their expected fractional loss given a certain hazard – say, shaking level). Thus, if we have a 100 times lower seismicity rate in New York compared to California, which at any given point from a given quake may yield a 2 times higher shaking level in New York compared to California because ground motions in the east are known to differ from those in the west; and if we have a 2 times higher asset density (a modest assumption for Manhattan!), and a 2 times higher vulnerability (again a modest assumption when considering the large stock of unreinforced masonry buildings and aged infrastructure in New York), then our California/New York ratio for annualized loss potential may be on the order of (100/(2x2x2)):1. That implies about a 12:1 risk ratio between the California and New York location, compared to a 100:1 ratio in seismicity rates.

From this example it appears that seismic awareness in the east may be more controlled by the rate of seismicity than by the less well understood risk potential. This misunderstanding is one of the reasons why earthquake awareness and preparedness in the densely populated east is so disproportionally low relative to its seismic loss potential. Rare but potentially catastrophic losses in the east compete in attention with more frequent moderate losses in the west. New York City is the paramount example of a low-probability, high-impact seismic risk, the sort of risk that is hard to insure against, or mobilize public action to reduce the risks.

There are basically two ways to respond. One is to do little and wait until one or more disastrous events occur. Then react to these – albeit disastrous – “windows of opportunity.” That is, pay after the unmitigated facts, rather than attempt to control their outcome. This is a high-stakes approach, considering the evolved state of the economy. The other approach is to invest in mitigation ahead of time, and use scientific knowledge and inference, education, technology transfer, and combine it with a mixture of regulatory and/or economic incentives to implement earthquake preparedness. The National Earthquake Hazard Reduction Program (NEHRP) has attempted the latter while much of the public tends to cling to the former of the two options. Realistic and reliable quantitative loss estimation techniques are essential to evaluate the relative merits of the two approaches.

The current efforts in the eastern U.S., including New York City, to start the enforcement of seismic building codes for new constructions are important first steps in the right direction. Similarly, the emerging efforts to include seismic rehabilitation strategies in the generally needed overhaul of the cities’ aged infrastructures such as bridges, water, sewer, power and transportation is commendable and needs to be pursued with diligence and persistence. But at the current pace of new construction replacing older buildings and lifelines, it will take many decades or a century before a major fraction of the stock of built assets will become seismically more resilient than the current inventory is. For some time, this leaves society exposed to very high seismic risks. The only consolation is that seismicity on average is low, and, hence with some luck, the earthquakes will not outpace any ongoing efforts to make eastern cities more earthquake resilient gradually. Nevertheless, M = 5 to M = 6 earthquakes at distances of tens of km must be considered a credible risk at almost any time for cities like Boston, New York or Philadelphia. M = 7 events, while possible, are much less likely; and in many respects, even if building codes will have affected the resilience of a future improved building stock, M = 7 events would cause virtually unmanageable situations. Given these bleak prospects, it will be necessary to focus on crucial elements such as maintaining access to cities by strengthening critical bridges, improving the structural and nonstructural performance of hospitals, and having a nationally supported plan how to assist a devastated region in case of a truly severe earthquake. No realistic and coordinated planning of this sort exists at this time for most eastern cities.

The current efforts by the Federal Emergency Management Administration (FEMA) via the National Institute of Building Sciences (NIBS) to provide a standard methodology (RMS, 1994) and planning tools for making systematic, computerized loss estimates for annualized probabilistic calculations as well as for individual scenario events, is commendable. But these new tools provide only a shell with little regional data content. What is needed are the detailed data bases on inventory of buildings and lifelines with their locally specific seismic fragility properties. Similar data are needed for hospitals, shelters, firehouses, police stations and other emergency service providers. Moreover, the soil and rock conditions which control the shaking and soil liquefaction properties for any given event, need to be systematically compiled into Geographical Information System (GIS) data bases so they can be combined with the inventory of built assets for quantitative loss and impact estimates. Even under the best of conceivable funding conditions, it will take years before such data bases can be established so they will be sufficiently reliable and detailed to perform realistic and credible loss scenarios. Without such planning tools, society will remain in the dark as to what it may encounter from a future major eastern earthquake. Given these uncertainties, and despite them, both the public and private sector must develop at least some basic concepts for contingency plans. For instance, the New York City financial service industry, from banks to the stock and bond markets and beyond, ought to consider operational contingency planning, first in terms of strengthening their operational facilities, but also for temporary backup operations until operations in the designated facilities can return to some measure of normalcy. The Federal Reserve in its oversight function for this industry needs to take a hard look at this situation.

A society, whose economy depends increasingly so crucially on rapid exchange of vast quantities of information must become concerned with strengthening its communication facilities together with the facilities into which the information is channeled. In principle, the availability of satellite communication (especially if self-powered) with direct up and down links, provides here an opportunity that is potentially a great advantage over distributed buried networks. Distributed networks for transportation, power, gas, water, sewer and cabled communication will be expensive to harden (or restore after an event).

In all future instances of major capital spending on buildings and urban infrastructures, the incorporation of seismically resilient design principles at all stages of realization will be the most effective way to reduce society’s exposure to high seismic risks. To achieve this, all levels of government need to utilize legislative and regulatory options; insurance industries need to build economic incentives for seismic safety features into their insurance policy offerings; and the private sector, through trade and professional organizations’ planning efforts, needs to develop a healthy self-protective stand. Also, the insurance industry needs to invest more aggressively into broadly based research activities with the objective to quantify the seismic hazards, the exposed assets and their seismic fragilities much more accurately than currently possible. Only together these combined measures may first help to quantify and then reduce our currently untenably large seismic risk exposures in the virtually unprepared eastern cities. Given the low-probability/high-impact situation in this part of the country, seismic safety planning needs to be woven into both the regular capital spending and daily operational procedures. Without it we must be prepared to see little progress. Unless we succeed to build seismic safety considerations into everyday decision making as a normal procedure of doing business, society will lose the race against the unstoppable forces of nature. While we never can entirely win this race, we can succeed in converting unmitigated catastrophes into manageable disasters, or better, tolerable natural events.

Quakeland: On the Road to America’s Next Devastating Earthquake: Revelation 6

             

Quakeland: On the Road to America’s Next Devastating Earthquake

Roger BilhamQuakeland: New York and the Sixth Seal (Revelation 6:12)

Given recent seismic activity — political as well as geological — it’s perhaps unsurprising that two books on earthquakes have arrived this season. One is as elegant as the score of a Beethoven symphony; the other resembles a diary of conversations overheard during a rock concert. Both are interesting, and both relate recent history to a shaky future.

Journalist Kathryn Miles’s Quakeland is a litany of bad things that happen when you provoke Earth to release its invisible but ubiquitous store of seismic-strain energy, either by removing fluids (oil, water, gas) or by adding them in copious quantities (when extracting shale gas in hydraulic fracturing, also known as fracking, or when injecting contaminated water or building reservoirs). To complete the picture, she describes at length the bad things that happen during unprovoked natural earthquakes. As its subtitle hints, the book takes the form of a road trip to visit seismic disasters both past and potential, and seismologists and earthquake engineers who have first-hand knowledge of them. Their colourful personalities, opinions and prejudices tell a story of scientific discovery and engineering remedy.

Miles poses some important societal questions. Aside from human intervention potentially triggering a really damaging earthquake, what is it actually like to live in neighbourhoods jolted daily by magnitude 1–3 earthquakes, or the occasional magnitude 5? Are these bumps in the night acceptable? And how can industries that perturb the highly stressed rocks beneath our feet deny obvious cause and effect? In 2015, the Oklahoma Geological Survey conceded that a quadrupling of the rate of magnitude-3 or more earthquakes in recent years, coinciding with a rise in fracking, was unlikely to represent a natural process. Miles does not take sides, but it’s difficult for the reader not to.

She visits New York City, marvelling at subway tunnels and unreinforced masonry almost certainly scheduled for destruction by the next moderate earthquake in the vicinity. She considers the perils of nuclear-waste storage in Nevada and Texas, and ponders the risks to Idaho miners of rock bursts — spontaneous fracture of the working face when the restraints of many million years of confinement are mined away. She contemplates the ups and downs of the Yellowstone Caldera — North America’s very own mid-continent supervolcano — and its magnificently uncertain future. Miles also touches on geothermal power plants in southern California’s Salton Sea and elsewhere; the vast US network of crumbling bridges, dams and oil-storage farms; and the magnitude 7–9 earthquakes that could hit California and the Cascadia coastline of Oregon and Washington state this century. Amid all this doom, a new elementary school on the coast near Westport, Washington, vulnerable to inbound tsunamis, is offered as a note of optimism. With foresight and much persuasion from its head teacher, it was engineered to become an elevated safe haven.

Miles briefly discusses earthquake prediction and the perils of getting it wrong (embarrassment in New Madrid, Missouri, where a quake was predicted but never materialized; prison in L’Aquila, Italy, where scientists failed to foresee a devastating seismic event) and the successes of early-warning systems, with which electronic alerts can be issued ahead of damaging seismic waves. Yes, it’s a lot to digest, but most of the book obeys the laws of physics, and it is a engaging read. One just can’t help wishing that Miles’s road trips had taken her somewhere that wasn’t a disaster waiting to happen.

Catastrophic damage in Anchorage, Alaska, in 1964, caused by the second-largest earthquake in the global instrumental record.

In The Great Quake, journalist Henry Fountain provides us with a forthright and timely reminder of the startling historical consequences of North America’s largest known earthquake, which more than half a century ago devastated southern Alaska. With its epicentre in Prince William Sound, the 1964 quake reached magnitude 9.2, the second largest in the global instrumental record. It released more energy than either the 2004 Sumatra–Andaman earthquake or the 2011 Tohoku earthquake off Japan; and it generated almost as many pages of scientific commentary and description as aftershocks. Yet it has been forgotten by many.

The quake was scientifically important because it occurred at a time when plate tectonics was in transition from hypothesis to theory. Fountain expertly traces the theory’s historical development, and how the Alaska earthquake was pivotal in nailing down one of the most important predictions. The earthquake caused a fjordland region larger than England to subside, and a similarly huge region of islands offshore to rise by many metres; but its scientific implications were not obvious at the time. Eminent seismologists thought that a vertical fault had slipped, drowning forests and coastlines to its north and raising beaches and islands to its south. But this kind of fault should have reached the surface, and extended deep into Earth’s mantle. There was no geological evidence of a monster surface fault separating these two regions, nor any evidence for excessively deep aftershocks. The landslides and liquefied soils that collapsed houses, and the tsunami that severely damaged ports and infrastructure, offered no clues to the cause.

“Previous earthquakes provide clear guidance about present-day vulnerability.” The hero of The Great Quake is the geologist George Plafker, who painstakingly mapped the height reached by barnacles lifted out of the intertidal zone along shorelines raised by the earthquake, and documented the depths of drowned forests. He deduced that the region of subsidence was the surface manifestation of previously compressed rocks springing apart, driving parts of Alaska up and southwards over the Pacific Plate. His finding confirmed a prediction of plate tectonics, that the leading edge of the Pacific Plate plunged beneath the southern edge of Alaska along a gently dipping thrust fault. That observation, once fully appreciated, was applauded by the geophysics community.

Fountain tells this story through the testimony of survivors, engineers and scientists, interweaving it with the fascinating history of Alaska, from early discovery by Europeans to purchase from Russia by the United States in 1867, and its recent development. Were the quake to occur now, it is not difficult to envisage that with increased infrastructure and larger populations, the death toll and price tag would be two orders of magnitude larger than the 139 fatalities and US$300-million economic cost recorded in 1964.

What is clear from these two books is that seismicity on the North American continent is guaranteed to deliver surprises, along with unprecedented economic and human losses. Previous earthquakes provide clear guidance about the present-day vulnerability of US infrastructure and populations. Engineers and seismologists know how to mitigate the effects of future earthquakes (and, in mid-continent, would advise against the reckless injection of waste fluids known to trigger earthquakes). It is merely a matter of persuading city planners and politicians that if they are tempted to ignore the certainty of the continent’s seismic past, they should err on the side of caution when considering its seismic future.