At the height of anxiety over local anthrax dispersal, leading engineers from throughout the United States met in Washington, D.C. Oct. 23-24, in an atmosphere of controlled urgency, to identify ways to lessen vulnerability of the nations infrastructure to terrorist attack.
The meeting showed that the “911” events — the suicide attacks on the World Trade Center and the Pentagon on Sept. 11 — are permanently changing engineering of buildings, bridges, highways, tunnels, power plants, waterworks and other critical infrastructure elements.
Terrorism protection and response is now as much a factor in construction as protection against earthquakes and other natural disasters. In panel presentations and roundtable brainstorming sessions, the engineers discussed such counter-terrorist measures as hardening structures against attack, monitoring bridges, tunnels and highways by thousands of microminiaturized sensors, protecting power plants and reservoirs, and providing better means of escape. The focus was on “thinking out of the box.”
The national conference, sponsored by the American Society of Civil Engineers (ASCE), The Civil Engineering Research Foundation (CERF), and the Building Futures Council, focused on a theme that was especially critical because of 911 — “Designing and Managing Vulnerability.”
“Our original program was going to be on networking and sharing information, but 911 changed that priority,” Harvey M. Bernstein, president and chief executive officer of CERF, told Construction Equipment Guide (CEG). “On the first week of October, we changed the theme to deal with the critical issue of vulnerability and got all new speakers except for two luncheon ones. The interest has been extremely high. Everybody wants to know what they can do to help. You need information to do that.”
A report on conference recommendations will be made available to federal and state officials.
Disaster Investigation
Members of the ASCE forensic team investigating the WTC tragedy over the past few weeks reported surprising initial findings. This team will submit a separate preliminary report in about six months, including recommendations on what can be done in the future for buildings identified as potential targets of terrorists.
Dr. James A. Milke, associate professor of fire protection engineering at the University of Maryland in College Park, MD, said the fire from 20,000 gals. of jet fuel in the plane that hit the North Tower “would last eight minutes; yet the fire burned one hour and 40 minutes.”
He later told CEG the fire could also have been fueled “by materials inside the building or inside the plane.” Milke pointed out that the collapses of the WTC buildings were the first of their type. Other high-rise buildings with protected steel columns had burned for longer periods without collapsing. These included the First Interstate Bank in Los Angeles, CA, (3.5 hours) and One Meridian Plaza in Philadelphia (l9 hours). The distortion point for steel is about 1,112 F (600 C); yet six tests in the United Kingdom showed steel withstanding 1,472 to 1,652 F (800 to 900 C).
Milke said the collapses of the two WTC towers could have been caused by any of three factors, or a combination of these factors: the impact of the aircraft, the fire, and the connections between the floor beams and the exterior vertical protected-steel columns that helped support the floors.
Members of the team indicated these bolt connections were not redundant. Severing them on one floor reportedly led to a “domino effect” when the floor fell on the one beneath. Investigators are aided by the fact that the floor number and location of each of these girder connections was marked and stamped during the original construction and can still be read as the pieces are excavated.
Yet many engineers at the conference said the trade center buildings had held up quite well considering the circumstances. They pointed out that most of the deaths had occurred above the impact locations of the two aircraft, that the buildings had included advanced security and escape systems since the previous terrorist attack in 1993, and that most of the people below the impact points had escaped, though the phased-evacuation procedures assumed the buildings would remain standing. Otherwise, they said, the casualties could have been as high as 30,000 people.
Daniel A. Cuoco, president and managing principal of LZA Technologies, confirmed to CEG that an emergency triage unit, set up soon after the attack under the North Bridge near the trade center, had been buried under debris that fell to the side when Tower Two collapsed. Some survivors were dug from this location on Sept. 12.
Dr. Bernard L. Meyers, senior advisor for Bechtel National Inc., said he had seen excavators still digging up “molten material” from the ground zero site. A separate “Pentagon Team” of the investigative group also visited the site of the suicide attack on the Pentagon, collecting complete information on the type of damage. Members are now analyzing this data and will soon start to prepare their report. The emphasis is on long-term measures.
“Cancer takes on a life of its own,” said one roundtable participant. “This [terrorism] is a cancer which will have a life of its own and which will be around a long time.”
Possible Remedies
Executive discussions by approximately eight people per table brainstormed a wide range of measures to prevent the disastrous chain of events of 911. One was placing numerous “smart system sensors” in high-rises and other structures that could tell firefighters whether it was safe to enter. Others included:
• Fire-resistant building structures.
• Access control — requiring full identification, checked against national computer records, before allowing people to enter certain structures.
• Skybridges between buildings for better escape. Parachutes for escape. (One person high on Tower One reportedly had a parachute, but never had the opportunity to use it.)
• Heliports on all buildings above a certain height, as is required in Los Angeles.
• More centralized emergency systems.
• Changes in heating, ventilation and air conditioning (HVAC) systems to make them more resistant to any type of attack.
• Better location of emergency personnel like the triage unit.
Highways, Bridges
and Surface Transportation
Christine M. Johnson, director of the Intelligent Transportation System (ITS) Joint Program Office at the Federal Highway Administration (FHWA) headquarters in Washington, told the conference that “Forty percent of terrorist attacks are against transportation facilities,” and that 911 means it’s a new world for the surface transportation industry and particularly the highway industry.”
In a subsequent interview with CEG, she explained: “Previously, we have never focused on vulnerability of facilities. We have focused on building, preserving and expanding, not nearly as much on their security.”
Asked how this applied to highways and bridges, she replied: “Only about 22 percent of highways and bridges in urban areas are instrumented. There’s really no excuse now for building an urban highway without command and sensing capability. New highways need to sense speed, volume, weather, and have visual contact through cameras. This can help to some extent in security because it provides more input for responding to disasters.
“Besides the threat of terrorist activity, we are having more and more natural disasters, compounded by the fact that human beings now live in more disaster-prone areas. We have to worry about managing highway systems flexibly for sudden evacuation.”
Although she seemed reluctant to discuss tunnels, Johnson told CEG the post-911 period is “an opportunity to modernize our bridge systems with more sensors.
“We do have the technologies for reading license plates, though I’m not sure that will solve the terrorist problem, and we already employ really good screening of drivers of hazardous materials.”
In her talk, Johnson said the FHWA has asked all states to identify critical assets “in terms of criticality of loss” and that some were implementing programs like placing cameras on vulnerable bridge structures, and inspecting these bridges two or three times a day.
She added that one or two states are now considering how to redesign certain facilities, relocate parking lots, and route rights-of-way so they would be farther from industrial facilities like power plants.
“Though surface transportation had guidelines in place at the time of 911, protective technology is a little more problematic on highway systems,” she said. “Cameras on bridges can be somewhat protective but more can be done.”
Johnson also expressed concern about evacuation of people.
“Our feeling is that there is greater vulnerability in the aftermath of a disaster,” she said. “Our highway and transit systems are already packed to the gills, and mass evacuation could be very problematic. State DOTs [Departments of Transportation] tend to not be fully utilized in disasters, where activity tends to be through FEMA [Federal Emergency Management Agency] and governors’ offices.
“The problem is to bring everything together,” Johnson added. “We need to bring ground transportation instrumentation systems up to the level of the aviation community in order to know what is happening and for use in emergencies. As frightening as 911 was, it has given us a tremendous opportunity to coordinate between transportation and public safety, to help plan and put in place the technology to operate with full information.”
Panelists also reported that an emergency plan carried out by PATH lines serving the WTC buildings probably saved thousands of lives. One PATH train, for instance, took survivors to Jersey City, NJ, just before the buildings collapsed. Other trains were rerouted back to Jersey City rather than stopping at the center.
Power Stations
Speakers expressed considerable concern about vulnerability of power stations.
“Damaging a major power plant substation or transmission line can initiate a series of events that can interrupt major portions of the U.S. electricity grid, which is all interconnected,” said Donald Mundy, vice president of the Power Delivery Division of Brown & Veatch Inc. “Interruption can be widespread because criminal activity increases when the lights go off. Outages can used to accomplish the confusion which could be used as cover for more serious terrorist acts.”
Mundy advocated expanding generating stations and installing many more closed circuit TV (CCTV) systems. “I’ve been to some power facilities which are protected by nothing more than a padlock,” he observed.
Mundy warned that the U.S. power transmission system is already congested, and that the generating load will grow by 20 percent in the next 10 years while transmission will grow only approximately 4 percent.
To lessen vulnerability, he suggested strengthening ties between the country’s three grid systems — East, West, and Texas — which are now relatively isolated, in order to transfer power more efficiently. He also suggested avoiding common corridors and shortening the distance between substations.
Subsequent roundtable suggestions included focusing on the most critical areas, adding fences, lights and other security steps at these areas.
Water Supplies
Although water supplies also are susceptible to terrorist activity, experts felt the quantities of water supplying urban and most towns, plus existing protective measures like chlorination and filtration, make it difficult to alter them sufficiently with chemical or biological agents to affect consumers.
However, they also saw possible vulnerabilities and they not taking any chances.
Jim Pendergast, special assistant to the interim director of the Environmental Protection Agency’s (EPA’s) Water Protection Task Force, said the task force is now assessing the biggest threat scenarios, paying particular attention to “making sure that emergency response teams check for things which so far have been under the radar.”
Pointing out that the United States includes 168,000 public water systems serving a 264-million people, with 600,000 mi. of pipes, Pendergast said the United States must protect source water, storage, treatment and distribution systems:
“Manholes, for instance, can provide access for placing hazardous materials into sewer systems. Utilities need to watch for tankers pumping into sewers.”
Brian Ramaley, director of the Newport News [VA] Waterworks and chairman of the industry’s Water Sector Critical Infrastructure Protection Advisory Committee, said top water officials initially focused on possible actions by people such as disgruntled employees “but now the focus has changed to terrorism.”
“Within a week of 911, an e-mail system was established so that warning can go to all water utilities simultaneously,” he said, also noting a concern often expressed at the conference: “We don’t want to give out too much information because it might help terrorists.
“Distribution systems with many miles of pipes are most susceptible,” he added. “It is critical that underground assessments be made. Government agencies and industry are also working on ways of detecting different substances, including anthrax and ecoli.” Ramaley said a special password-protected Web site has been established to provide critical information on safewater security. Other suggested steps include verifying all chemical deliveries, checking records of all employees, “vector analysis” to guard against infectious dosages, and developing remote sensors using “gas chromography the size of a thumbnail.
“The real need if for real-time radiological assessment,” Ramaley concluded. “Billions of dollars need to be spent over the next 10 to 20 years on environmental systems. It is critical that our preparedness not last for just a few years. Even if nothing happens in 10 to 20 years, we still need to design for terrorism, and treat it as if it were a seismic event.”
At subsequent roundtable discussions, other water officials told CEG small community water systems, because they handle less water, are probably the most vulnerable to terrorist action.
Osama bin Laden
Numerous engineers at the conference expressed concern that Osama bin Laden, thought to be the root cause, and probably instigator, of the terrorist attacks, is said to have both a civil engineering and public administration education. The son of a wealthy contractor in Saudi Arabia, bin Laden has built tunnels and highways in Afghanistan.
“I think you can expect, if he has an engineering background, that he is logical and analytical in how he lays out his attacks, and I think you see evidence of that in the way the attacks have gone forward,” Ramaley told CEG.
“From my perspective as an engineer, that’s scary because a logical and well-thought-out attack tends to be effective.”
Asked whether the terrorist plan might have included impacting the WTC towers at the location that would cause a collapse, he replied: “I’ve read the reports on the collapse and I’m not sure it’s a coincidence or not. I guess if you know much about structural engineering, and had done the calculations of the impact and that much fuel burning, you probably could have concluded that they were going to come down. I have read that the buildings were designed to withstand the impact from an airplane but not from a fully loaded 767.”
Said another attendee: “He [bin Laden] is not one of our illustrious members.” CEG
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