From Kevin Ryan two years ago and now.....food for thought - and then action. http://digwithin.net/[URL="https://digwithin.net/2015/08/08/fourteen-facts/"]

Fourteen Incredible Facts About 9/11[/URL]

It's important to remind people that we still don't know what happened on September 11, 2001. What is known about 9/11 is that there are many incredible facts that continue to be ignored by the government and the mainstream media. Here are fourteen.

1. An outline of what was to become the 9/11 Commission Report was produced before the investigation began. The outline was kept secret from the Commission's staff and appears to have determined the outcome of the investigation.
   
2. The 9/11 Commission claimed sixty-three (63) times in its Report that it could find "no evidence" related to important aspects of the crimes.
   
3. One person, Shayna Steinger, issued 12 visas to the alleged hijackers in Saudi Arabia. Steinger issued some of the visas without interviewing the applicants and fought with another employee at the embassy who tried to prevent her lax approach.
   
4. Before 9/11, the nation's leading counter-terrorism expert repeatedly notified his friends in the United Arab Emirates of top-secret U.S. plans to capture Osama bin Laden. These treasonous leaks prevented Bin Laden's capture on at least two separate occasions.
   
5. Former National Security Advisor Sandy Berger was caught stealing documents from the National Archives that had been requested by the 9/11 Commission. The Commission had previously been denied access to the documents but the White House reluctantly agreed to turn them over just as Berger was trying to steal them.
   
6. The official story of the failed air defenses on 9/11 was changed several times and, in the end, paradoxically exonerated the military by saying that the military had lied many times about its response. The man who was behind several of the changing accounts was a specialist in political warfare (i.e. propaganda).
   
7. Military exercises being conducted on the day of 9/11 mimicked the attacks as they were occurring and obstructed the response. NORAD commander Ralph Eberhart sponsored those exercises, failed to do his job that day, and later lied to Congress about it (if the 9/11 Commission account is true).
   
8. A third skyscraper collapsed late in the afternoon on 9/11. This was WTC 7, a 47-story building that the government's final report says fell into its own footprint due to office fires. The building's tenants included U.S. intelligence agencies and a company led in part by Donald Rumsfeld and Dick Cheney. Meetings were scheduled there to discuss terrorism and explosives on the morning of 9/11.
   
9. News agencies, including BBC and CNN, announced the destruction of WTC 7 long before it happened. One BBC reporter announced the collapse while viewers could see the still-standing building right behind her in the video. Years later, after claiming that it had lost the tapes and then found them again, BBC's answer to this astonishing report was that everything was just "confusing and chaotic" that day. Of course, one problem with this is that the news agencies predicted the exact building, of the many damaged in the area, that would collapse. Another big problem is that no one could have possibly predicted the collapse of WTC 7 given the unprecedented and unbelievable official account for how that happened.
   
10. Construction of the new, 52-story WTC 7 was completed two years before the government knew what happened to the first WTC 7. In fact, when the new building was completed in 2006, the spokesman for the government investigation said, "We've had trouble getting a handle on building No. 7." The construction of the new building, without regard for how the first one was destroyed, indicates that building construction professionals in New York City did not believe it could ever happen again.
    
11. Ultimately, building construction codes were not changed as a result of the root causes cited by the National Institute for Standards and Technology for destruction of the World Trade Center (WTC) buildings. This fact shows that the international building construction community does not believe that the WTC buildings were destroyed as stated in the official account.
    
12. AMEC, the company that just finished rebuilding the exact spot where Flight 77 was said to hit, was put in charge of cleanup at the WTC and the Pentagon. The man who ran the company, Peter Janson, was a long-time business associate of Donald Rumsfeld.
    
13. The response of the U.S. Secret Service to the 9/11 attacks suggests foreknowledge of the events in that the agency failed to protect the president from the obvious danger posed by terrorists.
    
14. The U.S. Securities and Exchange Commission notified the FBI of suspected 9/11 insider trading transactions. That evidence was ignored and the suspects were not even questioned by the FBI or the 9/11 Commission.
    

Sixteen More Reasons to Question 9/11

It has been 16 years since the crimes of September 11th, 2001. In that time, facts have been revealed that led more than a third of Americans to believe that the U.S government was involved in the attacks. This blog noted 14 such incredible facts on the 14th anniversary of the crimes. Here are 16 more.

1. In the nine years before 9/11, the FBI failed miserably at preventing terrorism. There are many examples of how FBI leadership under director Louis Freeh facilitated and covered-up acts of terrorism during this time. After 9/11, the FBI took extraordinary measures to hide evidence related to the attacks.
   
2. CIA director George Tenet led an agency that also failed in its duties related to counterterrorism and those failures appear to have been intentional. Like Freeh, Tenet had developed secret paths of communication with Saudi authorities. The facts suggest that Tenet facilitated the crimes of 9/11.
   
3. The FBI and CIA have made a mockery of the U.S. justice system as it relates to 9/11. While these agencies are suspected of involvement, they have charged others with the crimes using secret evidence in a secret military trial. The accused have been held in seclusion for nearly 15 years while FBI and CIA agents attempt to insert themselves as defense team members, ensuring total control of the narrative.
   
4. CIA officers responsible for identifying deception in others fail to notice that the characteristics of deception are amply demonstrated when government representatives respond to questions about 9/11.
   
5. There have been four, distinctly different, official accounts given for how the North American air defense system failed to intercept any of the hijacked planes. The last account says that dozens of military officers spent years lying to Congress, the 9/11 Commission, and everyone else, in ways that made the military look bad. Few observers considered the simpler explanationthat the 9/11 Commission lied to divert attention from many difficult questions.
   
6. Parts of the official account of 9/11 are based on the highly improbable flight path of a military cargo plane called Gofer 06. The crew of this plane witnessed the crashes of two of the four planes that day despite those crashes occurring 127 miles and less than 30 minutes apart.
   
7. There are dozens of unanswered questions about the events at the Pentagon and the plane that reportedly crashed there.
   
8. The 19 young men accused within 72-hours of the attacks were known to enjoy strip bars, alcohol, drugs, and other things that are clearly non-Muslim activities. Moreover, these suspects were not capable of accomplishing most of what was needed to pull off the crimes.
   
9. Mohamed Atta, the man called the "9/11 ringleader," had a lot in common with Lee Harvey Oswaldthe man accused of killing President Kennedy. Both Atta and Oswald were suspected of using illicit drugs, seemed to be protected by authorities, and were associated with CIA-linked entities.
   
10. The New York Times led the propaganda behind the U.S. invasion of Iraq in 2003 and it also led the propaganda behind the cover-up of the 9/11 crimes. It did so by ignoring many of the most relevant facts, by promoting false official accounts, and by belittling those who questioned the 9/11 events.
    
11. On the day of the attacks, firefighters, journalists, survivors, and eyewitnesses testified to secondary explosions in the World Trade Center buildings. Videos of these testimonies were held secret for years by the government agency NIST and released only via FOIA request after public interest died down. Scientists have explained that the towers came down due to explosions and that the NIST investigation was fraudulent.
    
12. Among the evidence ignored by the mainstream media are many facts indicating the presence of thermite at the World Trade Center. Thermite is a chemical mixture that can be used to melt and cut structural steel. Instead of addressing this evidence, supporters of the official account have engaged in deception and distraction in order to obfuscate the facts.
    
13. Despite recent, worldwide protests against the abuse of science, the most glaring example of politically motivated pseudoscience continues to be ignored by many scientists. That is the 7-year sequence of contradictory explanations provided by U.S. government investigators for the destruction of the WTC buildings.
    
14. Links between 9/11 and the 1995 bombing in Oklahoma City lead to questions about the company that controlled security for many of the facilities impacted on 9/11, including the WTC complex. For instance, that WTC security company shared the same OKC airport office later occupied by the flight trainer for Zacarias Moussaoui, the alleged "20th" hijacker.
    
15. Media and certain government representatives have hinted at Saudi Arabian ties to the 9/11 crimes. However, those hints always omit the most interesting links between the 9/11 attacks and Saudi Arabialinks that implicate powerful people in the United States.
    
16. When the long-awaited 28 pages missing from the Congressional Joint Inquiry Report into 9/11 were finally released, those pages reinforced concerns that deep state players were involved in the attacks. Such players include Wirt D. Walker, the CEO of the WTC security company, who is clearly associated with top-secret operations.
    

As the crimes of 9/11 continue to go unsolved and largely unquestioned, Americans should be aware that another 9/11 could happen at any time. If it does, the ongoing failure to question obvious deception in terrorism could take society to places where freedom to question is no longer an option.

Quote:[FONT=&amp]Saudi government may have funded 9/11 dry run', attorneys say

#SaudiStruggle

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[FONT=&amp]New evidence submitted in lawsuit on behalf of families of 1,400 victims who died in terrorist attacks 16 years ago


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[FONT=&amp]New York's World Trade Center under attack in 2001 (AFP/file photo)[/FONT]
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Saturday 9 September 2017 20:51 UTC


Last update:
Sunday 10 September 2017 0:27 UTC





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[FONT=&amp]New evidence submitted in a lawsuit against the Saudi Arabian government shows its embassy in Washington may have funded a 9/11 "dry run" by two Saudis, possibly reinforcing the claim that employees and agents of the kingdom directed and aided the 9/11 hijackers, the New York Post reported on Saturday.
Two years before the airliner attacks, the Saudi Embassy paid for two nationals living in the US as students to fly from Phoenix to Washington "in a dry run for the 9/11 attacks," alleges the amended complaint filed on behalf of the families of some 1,400 victims who died in the terrorist attacks 16 years ago, the Post said.
The court filing provides new details that paint "a pattern of both financial and operational support" for the 9/11 conspiracy from official Saudi sources, lawyers for the plaintiffs say. They added that the Saudi government may have been involved in underwriting the attacks from the earliest stages, including testing cockpit security.
Motion to dismiss

"We've long asserted that there were longstanding and close relationships between al Qaeda and the religious components of the Saudi government," said Sean Carter, the lead attorney for the 9/11 plaintiffs. "This is further evidence of that."
Lawyers representing Saudi Arabia last month filed a motion to dismiss the lawsuit, which may finally be headed towards trial now that Congress has cleared diplomatic-immunity hurdles, the Post said. A Manhattan federal judge has asked the 9/11 plaintiffs, represented by lead law firm Cozen O'Connor, to respond to the motion by November.
Saudi Arabia had called on the United States last year to "correct" the bill that allows 9/11 victims' families to sue Saudi Arabia in US courts to avoid its "dangerous" consequences.
An unidentified Saudi foreign ministry official told Saudi news agency SPA at the time that he hoped wisdom would prevail in Congress to amend the Justice Against Sponsors of Terrorism Act (JASTA).

Saudi Arabia asks to be dropped from 9/11 lawsuit

Congress voted overwhelmingly last September to override a presidential veto of the bill by then President Barack Obama.
Families of 9/11 victims campaigned for the law, alleging that the Saudi government had a hand in the attacks that killed almost 3,000 people.
Fifteen of the 19 hijackers were Saudi citizens, but no link to the government has been proven. The Saudi government denies any links to the plotters.
Declassified documents showed US intelligence had multiple suspicions about links between the Saudi government and the attackers.
Riyadh lobbied

"While in the United States, some of the 9/11 hijackers were in contact with, and received support or assistance from, individuals who may be connected to the Saudi government," a finding read.
Behind the scenes, Riyadh has lobbied furiously for the bill to be scrapped.
A senior Saudi prince reportedly threatened to pull billions of dollars out of US assets if it became law, but Saudi officials later distanced themselves from that.
In a diplomatic protest note obtained by AFP, the European Union warned the rules would be "in conflict with fundamental principles of international law".
"State immunity is a central pillar of the international legal order," the "demarche" noted, adding that other countries may take "reciprocal action".
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[FONT=&amp]The Environmentalist
March 2009, Volume 29, Issue 1, pp 5663

Environmental anomalies at the World Trade Center: evidence for energetic materials

• Kevin Ryan
  
• James R. Gourley
  
• Steven E. Jones
  

ArticleFirst Online: 04 August 2008


Abstract

Investigators monitoring air quality at the World Trade Center, after the September 11th attacks, found extremely high levels of volatile organic chemicals as well as unusual species that had never been seen before in structure fires. Data collected by the U.S. Environmental Protection Agency indicate striking spikes in levels of benzene, styrene, and several other products of combustion. These spikes occurred on specific dates in October and November 2001, and February 2002. Additionally, data collected by researchers at the University of California Davis showed similar spikes in the levels of sulfur and silicon compounds, and certain metals, in aerosols. To better explain these data, as well as the unusual detection of 1,3-diphenylpropane, the presence of energetic nanocomposites in the pile at Ground Zero is hypothesized.
Keywords

World Trade Center EPA 1,3-diphenylpropane Aluminothermics Energetic nanocomposites Volatile organic chemicals

[FONT=&amp]Download fulltext PDF
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[FONT=&amp]1 [/FONT]Introduction

For months after the destruction at the World Trade Center (WTC) on 11th September, 2001, the fires at Ground Zero (GZ) could not be put out, despite the following facts.

• Several inches of dust covered the entire area after the destruction of the WTC buildings.
  
• Millions of gallons of water were sprayed onto the debris pile.
  
• Several rainfall events occurred at GZ, some heavy; and
  
• A chemical fire suppressant called Pyrocool was pumped into the piles (Lipton and Revkin [FONT=&amp]2001[/FONT]).
  

The characteristics of these un-extinguishable fires have not been adequately explained as the results of a normal structure fire, even one accelerated by jet fuel. Conversely, such fires are better explained given the presence of chemical energetic materials, which provide their own fuel and oxidant and are not deterred by water, dust, or chemical suppressants.
Apart from the extensive but failed efforts to extinguish the fires, there are several other physical indicators of the presence of energetic chemical reactions in the rubble at GZ. These include the following.

1. 1.Photographs and witness testimony evidencing molten metal and explosions accompanied by white dust clouds (Jones [FONT=&amp]2006[/FONT]; Meyerowitz [FONT=&amp]2006[/FONT]; PBS [FONT=&amp]2002[/FONT]).
   
2. 2.Extremely high temperatures in the fires at the WTC (Jones et al. [FONT=&amp]2008a[/FONT]).
   
3. 3.Unusual spikes in volatile organic chemical (VOC) emissions, suggesting abrupt, violent fires on specific dates.
   
4. 4.Unusual species in the environmental monitoring data, also corresponding to specific dates.
   

Explosions followed by white dust clouds, and molten metal at GZ, are of particular interest in this analysis. A white dust cloud is one of the products of the thermite reaction. The white dust in this case is aluminum oxide, released from the extremely exothermic reaction between aluminum and iron oxide. The other product of the thermite reaction is molten iron. These facts, coupled with evidence for extremely high temperatures at the WTC, suggest that investigators should examine the potential for such pyrotechnic materials at the WTC. The environmental data described below give more compelling evidence to support such an inquiry.

[FONT=&amp]2 [/FONT]EPA data on VOC emissions from GZ

Through a Freedom of Information Act (FOIA) request, access to environmental monitoring data from the U.S. Environmental Protection Agency's (EPA) WTC response was obtained (EPA [FONT=&amp]2004[/FONT]). The data set shows that spikes in the levels of airborne VOCs occurred on specific dates at GZ (Austin Tobin Plaza, WTC 1 or WTC 2), with levels of the related contaminants rising sharply and then falling dramatically back to baseline levels, usually within 1 day or less. An example is shown in Fig. [FONT=&amp]1[/FONT], for detections of benzene.Open image in new window
[FONT=&amp]Fig. 1[/FONT]EPA maximum daily detection of benzene in air at GZ, September through November 2001


Benzene is a major product of the combustion of plastics and other organic materials. In a typical structure fire, when plastics are abundant, benzene levels have been seen at levels as high as 26 ppb (MOEE [FONT=&amp]1997[/FONT]). Apart from fires, benzene is seen in high-traffic areas of urban settings, with mean levels of ~4 ppb (Crebellia et al. [FONT=&amp]2001[/FONT]).
Serious health consequences are known to occur when breathing benzene at 100 ppb, and it is known to cause diseases such as leukemia (HHS [FONT=&amp]2007[/FONT]). Note that, for the first few weeks after 9/11, the levels of benzene detected at GZ were relatively low, although perhaps higher than historical levels from structure fires. But the maximum value detected in November 2001 was 180,000 ppb, and the average daily detection for October and November 2001 was 18,000 ppb. The five peaks in benzene detection occurred on 5th October, 11th October, 3rd November, 8th November, and 16th November.
Similarly, the data for styrene are presented in Fig. [FONT=&amp]2[/FONT].Open image in new window
[FONT=&amp]Fig. 2[/FONT]EPA maximum daily detection of styrene in air at GZ, September through November 2001


The spikes in detected levels of styrene are more prominent. Styrene is normally seen as a product of the combustion of plastics, notably polystyrene. Interestingly, the dates of the five highest levels of styrene detection occurred on the same dates as those of highest detection of benzene.
A similar pattern in detection was noted in the data for several other analytes monitored by EPA in the air above the rubble piles at GZ. For example, toluene, ethylbenzene, and propylene follow the same pattern of spiked detection levels as seen above. These FOIA-obtained data indicate that all five of these VOCs were detected far above the levels published by EPA in their reports for the general public (Fig. [FONT=&amp]3[/FONT], EPA [FONT=&amp]2002[/FONT]).Open image in new window
[FONT=&amp]Fig. 3[/FONT]EPA maximum daily detection of VOCs in air at GZ, September through November 2001


The occurrence of such extreme, sharp spikes in VOCs in air at GZ indicate something other than the behavior of a typical structure fire. Oxygen influx as a result of shifting of materials within the pile might have created an increase in combustion of material in localized areas. But these spikes in VOCs, at levels thousands of times higher than seen in other structure fires, suggest extremely violent but short-lived fire events.
Probably the most striking spike in toxic air emissions, found in EPA monitoring data, occurred on 9th February, 2002. Note (Table [FONT=&amp]1[/FONT]) that this was nearly 5 months after 9/11, and after nearly all the debris had been cleared from GZ. In fact, the levels of some species, like toluene and styrene, were some of the highest observed at the site. But the levels of benzene and propylene detected on that day were far above previous measurements, at 610,000 and 990,000 ppb, respectively. Other VOCs were measured at their peak levels on this date, including 1,3-butadiene at 400,000 ppb.[FONT=&amp]Table 1[/FONT]Six dates of maximum detection for five species in air at GZ (ppb)


[TABLE="width: 885"]
[TR]
[TH="bgcolor: #F2F2F2, align: left"]Analyte[/TH]
[TH="bgcolor: #F2F2F2, align: left"]5th October[/TH]
[TH="bgcolor: #F2F2F2, align: left"]11th October[/TH]
[TH="bgcolor: #F2F2F2, align: left"]3rd November[/TH]
[TH="bgcolor: #F2F2F2, align: left"]8th November[/TH]
[TH="bgcolor: #F2F2F2, align: left"]16th November[/TH]
[TH="bgcolor: #F2F2F2, align: left"]9th February[/TH]
[/TR]
[TR]
[TD]Benzene[/TD]
[TD]86,000[/TD]
[TD]58,000[/TD]
[TD]83,000[/TD]
[TD]180,000[/TD]
[TD]73,000[/TD]
[TD]610,000[/TD]
[/TR]
[TR]
[TD]Ethylbenzene[/TD]
[TD]48,000[/TD]
[TD]23,000[/TD]
[TD]95,000[/TD]
[TD]67,000[/TD]
[TD]34,000a[/TD]
[TD]5,000[/TD]
[/TR]
[TR]
[TD]Propylene[/TD]
[TD]56,000[/TD]
[TD]37,000[/TD]
[TD]49,000[/TD]
[TD]92,000[/TD]
[TD]66,000[/TD]
[TD]990,000[/TD]
[/TR]
[TR]
[TD]Toluene[/TD]
[TD]40,000[/TD]
[TD]23,000[/TD]
[TD]67,000[/TD]
[TD]74,000[/TD]
[TD]23,000[/TD]
[TD]45,000[/TD]
[/TR]
[TR]
[TD]Styrene[/TD]
[TD]15,000[/TD]
[TD]180,000[/TD]
[TD]56,000[/TD]
[TD]40,000[/TD]
[TD]64,000b[/TD]
[TD]17,000[/TD]
[/TR]
[/TABLE]

aMeasured on 18th November
bMeasured on 14th November



EPA also monitored very fine particulate matter (PM) and other sizes of PM. PM is probably the most reliable indicator for the activity of structure fires, as such fires are generally known to burn incompletely, and produce PM that drifts up and outward from the source. EPA data from the West Broadway sampling site, the location closest to GZ where PM was monitored, show the following trend in very fine PM (PM2.5, or all particles <2.5 μm) in October and November 2001 (Fig. [FONT=&amp]4[/FONT]).Open image in new window
[FONT=&amp]Fig. 4[/FONT]Very fine PM detected in air by EPA near GZ in late 2001


These data show that the peaks in levels of very fine PM near GZ correspond to different dates than the peaks for the previously discussed combustion products. The five strongest peaks in PM2.5 levels are centered on 23th, 26th September, and 3rd, 10th, 20th October, closer in time to the events of 9/11. None of these dates correspond to the dates of five peaks in VOCs noted above. Additionally, it is clear that the levels of PM2.5 emissions rose more gradually, and died down more gradually, indicating slower fire dynamics as might be expected from the burning of the organic materials previously thought to exist in the WTC.
These data suggest that the greatest level of fire activity, associated solely with the typical fuel sources expected in the WTC, was completed by the third week of October. That is, the materials expected to burn (incompletely) in a structure fire, producing PM, were largely burned off by mid- to late-October.
Therefore, the extreme spikes in air concentrations of the five VOCs noted above, particularly on 3rd, 8th November, and 9th February, point not to other sources of typical combustible materials but to other forms of combustion. Such forms of combustion appear to be violent and short-lived, and thus similar to the effects of energetic materials, like thermite.

[FONT=&amp]3 [/FONT]Aerosol measurements after 9/11

Thomas Cahill, of the University of California Davis, reported similar unusual environmental data collected near GZ, although only through the month of October 2001. Cahill's team monitored for the presence of aerosols at a distance of ~1.8 km (1.1 mile) from GZ during this time.
The data produced by this team were difficult to explain. For example, with regard to more coarse particles detected in the air at GZ, the following statements were made.

"These particles simply should not be there," Cahill said. "It had rained, sometimes heavily, on six days in the prior three weeks. That rain should have settled these coarse particles." (Wright [FONT=&amp]2002[/FONT])

With respect to fine particles, Cahill and his team saw three problems with the data, and explained those basic problems in this manner.

• We see very fine aerosols typical of combustion temperatures far higher than [expected in] the WTC collapse piles.
  
• We see some elements abundantly and others hardly at all, despite similar abundances in the collapse dust.
  
• We see organic species in the very fine mode that would not survive high temperatures (Cahill et al. [FONT=&amp]2003[/FONT]).
  

According to Cahill, the very fine particles found contained high levels of sulfur and/or sulfur-based compounds, as well as high levels of very fine (chemically bound) silicon. Note that Cahill's team used synchrotron X-ray fluorescence to measure elements in air, and therefore did not distinguish between these elements and their compounds.
The silicon compounds were conjectured to originate from thousands of tons of glass in the debris. The metals found by Cahill's team in relatively high concentrations were iron, titanium, vanadium, nickel, copper, and zinc. Although the sources of some of these metals were not described precisely, Cahill suggested that iron and titanium were "associated with powdered concrete," and vanadium and nickel were "often associated with fuel-oil combustion" (Wright [FONT=&amp]2002[/FONT]).
Interestingly, the Cahill data exhibited similar dramatic peaks in maximum detection related to some elements, particularly silicon compounds. Although the measurements made by this group were reported only for October, the dates 5th and 11th October stand out as peak maxima for silicon, corresponding to the dates in October of peak detections for benzene, ethylbenzene, propylene, styrene, and toluene. Cahill's team made the following statements about silicon being dominant, and other similar species being absent, in what they called the very fine mode.

Silicon dominates all other elements, unlike the coarse mode aerosols… (Cahill et al. [FONT=&amp]2004[/FONT])

other crustal elements (Al, Ca, and iron) seen so abundantly in the coarser particles are essentially absent in this very fine mode. (Cahill 2003)

In July of 2002, Cahill reported that (emphasis added)

The air from Ground Zero was laden with extremely high amounts of very small particles, probably associated with high temperatures in the underground debris pile. (ENS [FONT=&amp]2002[/FONT])

But by September 2002, Cahill appeared to have changed his mind on the "high temperatures," and attempted to explain some of the unusually high levels of metals in his data by invoking a new mechanism of "anaerobic incineration." Because the existence of high-temperature fires, necessary to volatilize such metals, was not compatible with the common understanding that only typical fuel sources could be involved, it was proposed that chlorine was present at concentrations of ~10%, causing the metals to volatilize at lower temperatures (Cahill et al. [FONT=&amp]2003[/FONT]; Dalton [FONT=&amp]2003[/FONT]).
This hypothesis for the volatilization of metals is not well defined. It is clear that 10% chlorine gas could not be the reactive species in Cahill's hypothesis, but as stated before, it is also clear that Cahill and his team did not distinguish between elemental forms and compounds. Chlorine gas, which is highly reactive, would not form at 10% in air in such an environment, and if it did it would have been fatal to workers in the area. But chlorinated compounds are generated in structure fires. Perhaps Cahill was proposing a gradient of concentrations for such compounds in air around the pile, with a concentration of 10% being coincidentally located around the fuel oil source for vanadium and nickel.
The only fuel oil source suggested by Cahill and his team was under WTC building 7, across the street from the towers (Cahill et al. [FONT=&amp]2004[/FONT]). But it should be noted that government investigators have suggested that the fuel oil in question was burned to create the fires that caused WTC building 7 to collapse. If one assumes they were correct, that fuel oil would no longer be available as the source of vanadium and nickel more than 1 month later.
Additionally, Cahill's hypothesis seems to require a complicated, multi-step process of metal chlorination in the pile and then de-chlorination after oxygen and/or water levels returned, in order to allow for the species measured 1.8 km away.

The mechanism proposed is then the formation of gasses in the oxygen-poor, chlorine rich collapse piles, emission through the rubble and conversion at or near the surface into oxidized forms and thus very fine particles. (Cahill et al. [FONT=&amp]2003[/FONT])

A better explanation for the data collected involves the presence of short-lived, violent fires at GZ. A typical modern day form of thermite, used in military devices for metal cutting, is thermate, with finely powdered sulfur added as part of a flare mixture. Additionally, aluminothermic materials can explain the presence of unusual metals and silica in fine PM, as described below.

[FONT=&amp]4 [/FONT]The unusual detection of 1,3-diphenylpropane

Cahill did not have an explanation for the third part of the problem that his team saw. That is, what effect at the WTC would cause organic compounds in very fine aerosols that would not survive high temperatures? Although Cahill did not specifically identify these organic species, EPA did mention one. This analyte detected by EPA may be the most interesting in the environmental data from the WTC: 1,3-diphenylpropane [abbreviated 1,3-DPP with IUPAC name 1′,1′-(1,3-propanediyl)bis-benzene].
EPA's Erik Swartz stated that 1,3-DPP was present at levels "that dwarfed all others." Swartz went on to say"We've never observed it in any sampling we've ever done" (Garrett [FONT=&amp]2003[/FONT]). An EPA publication on the findings stated:

This species has not previously been reported from ambient sampling. It has been associated with polyvinyl chloride materials, which are believed to be in abundance at the WTC site. These emissions lasted for over three weeks (9/26/01-10/20/01) after the initial destruction of the WTC. (EPA [FONT=&amp]2006[/FONT])

The fact that this species had never been found before is a startling fact, considering that EPA has monitored extreme structure fires before, including those in which polyvinyl chloride (PVC) materials were present. In fact,

EPA officials and fire-fighting experts were well aware, from previous studies of a handful of spectacular and tragic fires in hotels, commercial buildings and downtown areas, that such blazes are capable of releasing a witch's brew of some of the most toxic substances knownincluding mercury, benzene, lead, chlorinated hydrocarbons and dioxins. (Gonzalez [FONT=&amp]2002[/FONT])

EPA's history with structure fire monitoring indicates that, to have never seen an organic compound like 1,3-DPP is very unusual, especially when it was found at such high levels. But 1,3-DPP was not only at high levels, it was also reported to have been "pervasive" (American Scientist [FONT=&amp]2003[/FONT]).
Considering how unusual, abundant, and pervasive 1,3-DPP was reported to be, it is remarkable that EPA released only five results for this compound, and all of these from only one locationthe 290 Broadway site of EPA itself. But even at this one site, its clear that 1,3-DPP was measured at levels that were as much as 30 times greater than typical semi-volatile organic combustion products like naphthalene and biphenyl. Additional details about EPA's measurements of 1,3-DPP will have to wait. Repeated delays in the fulfillment of the FOIA mentioned above, and a response letter indicating EPA will withhold a majority of the related documents, suggest that EPA has more data on 1,3-DPP but is reluctant to release it.
Unlike the EPA publication, Swartz did not attribute the high levels of 1,3-DPP to the combustion of PVC. In fact, there are no readily available references to indicate how 1,3-DPP is "associated with PVC," and the pathway of such degradation via combustion would be complicated, at best.
Instead, Swartz attributed the presence of 1,3-DPP to polystyrene and other plastics, by stating

[1,3-DPP was] primarily found in the gas phase (with 90% of the mass found on the front denuder). Although the source of the compound in this study is not known, it may have formed during the combustion of polystyrene or other polymers. 1,3-Diphenylpropane has been found to co-occur with polystyrene plastics (37, 38), so another possibility is that the compound was already present and encapsulated in large volumes of plastics in the buildings and was off-gassed during the pulverization process. (Swartz et al. [FONT=&amp]2003[/FONT])

However, the sources Swartz uses to support 1,3-DPP as a combustion product of polystyrene are not studies of polystyrene combustion, but of gasses released in the long-term degradation of enclosed polystyrene food product packaging.
Other studies have shown trace amounts of 1,3-DPP as a secondary product of polystyrene combustion or thermolysis. But such studies suggest that 1,3-DPP may only form in negligible quantities and under certain conditions (Boettner et al. [FONT=&amp]1973[/FONT]; McCaffrey et al. [FONT=&amp]1996[/FONT]). In such experiments, the major product of the combustion or thermolysis of polystyrene, far outweighing others, is the monomer styrene. This leads us to the fact that, although styrene was a species of interest at 290 Broadway during the same time period as was 1,3-DPP, styrene detections were not reported in the FOIA provided data (EPA [FONT=&amp]2004[/FONT]). Therefore, it appears that Swartz' first suggested hypothesis, that 1,3-DPP resulted from combustion of polystyrene, is not probable.
The possibility that 1,3-DPP was off-gassed as a result of the physical destruction of debris at GZ, as in Swartz' second hypothesis, seems possible. But it is one thing to suggest that 1,3-DPP was "encapsulated in large volumes of plastics in the buildings" and another thing to state in what exact materials this rare compound was encapsulated. Consumer plastics do not typically have large amounts of unusual organic compounds just simply "encapsulated" within them.
A review of the literature uncovers one interesting source of encapsulated 1,3-DPP that may help to explain much of the unusual environmental data described above. The synthesis of novel nanostructured materials has involved the use of 1,3-DPP to functionalize mesoporous silicas through control of pore size (Kidder et al. [FONT=&amp]2003[/FONT]).

The resulting novel hybrid materials possess silyl aryl ether linkages to the silica surface that are thermally stable to ca. 550°C, but can be easily cleaved at room temperature with aqueous base for quantitative recovery of the organic moieties. (Kidder et al. [FONT=&amp]2005[/FONT])

Such novel nanostructured materials are known to have been the focus of intense research in the past 10 years, particularly with regard to energetic nanocomposites. Energetic nanocomposites are hybrid solgel materials, often made with a silica base, that have been combined with metal oxides and nano-scale aluminum powder to form superthermite materials. Much of this work has been done at Lawrence Livermore National Laboratories (Gash et al. [FONT=&amp]2000[/FONT]; Clapsaddle et al. [FONT=&amp]2004[/FONT], [FONT=&amp]2005[/FONT]; Simpson et al. [FONT=&amp]2004[/FONT]).
Similar energetic nanocomposites have been known to be amenable to spray-on applications. In fact, some investigators have reported that

The sol-gel process is very amenable to dip-, spin-, and spray-coating technologies to coat surfaces. We have utilized this property to dip-coat various substrates to make sol-gel Fe2O3/Al/Viton coatings. The energetic coating dries to give a nice adherent film. Preliminary experiments indicate that films of the hybrid material are self-propagating when ignited by thermal stimulus. (Gash et al. [FONT=&amp]2002[/FONT])

Apart from iron oxide, other metallic oxides commonly used as oxidizers in various forms of thermite mixtures include MoO3 and CuO (Prakash et al. [FONT=&amp]2004[/FONT]). Although EPA did not test for molybdenum, the data show a dramatic spike in copper detection on 8th October. Note that EPA's analysis of metals in air samples utilized inductively coupled argon plasma, and therefore also did not distinguish between these metals and their compounds.
It is worth noting that the United States Geological Survey (USGS) found and studied one or more molybdenum spheres in the WTC dust (Jones et al. [FONT=&amp]2008a[/FONT]). This fact gives evidence for the presence of molten molybdenum, and therefore possibly the related, high temperature aluminothermic reaction.

[FONT=&amp]5 [/FONT]Hypothesis for release of 1,3-DPP and other unusual species at WTC

If energetic nanocomposites were present at the WTC, the presence of 1,3-DPP might be explained through a mechanism of release from the silica microstructure by aqueous base. As noted above, the silyl aryl ether linkage of the composite is "thermally stable to ca. 550°C" but yet, the organic moieties "can be easily cleaved at room temperature with aqueous base for quantitative recovery." The dust at GZ was known to be highly basic (Jenkins [FONT=&amp]2007[/FONT]), and combined with the large amount of water from fire-fighting efforts and rainfall, undoubtedly produced aqueous base throughout the pile.
It is important to understand that 1,3-DPP would not have been directly released from the silica microstructure via the route of aqueous base. It would have been the hydroxyl derivative, p-(3-phenylpropyl)phenol, abbreviated as HODPP, that was first released in this manner.≅Si-O-DPP+ROH→≅Si-OR+HODPP.≅Si-O-DPP+ROH→≅Si-OR+HODPP.



But the pores of an energetic nanocomposite are also filled with a mixture of fine aluminum powder, and one or more finely dispersed metal oxides. Therefore, hydrogen gas could have evolved in the following way (as well as by several other reaction mechanisms in the high-temperature environment of GZ combustion).2Al +6H2O→2Al(OH)3+3H2.2Al +6H2O→2Al(OH)3+3H2.



Production of 1,3-DPP might then have followed from a metal oxide-catalyzed reaction of p-(3-phenylpropyl)phenol with hydrogen. A similar reduction of phenol to benzene, catalyzed by MoO3, has been reported (Woodward and Glover [FONT=&amp]1948[/FONT]).MoO3+ H2→ MoO2+ H2O,MoO3+ H2→ MoO2+ H2O,


HODPP+ MoO2→1,3-DPP+ MoO3.HODPP+ MoO2→1,3-DPP+ MoO3.



Other pathways have been proposed for the release of 1,3-DPP, some without the need for preliminary reactions, but experiments are required to confirm these possibilities.
Based on currently released data, maximum detections for 1,3-DPP (at 290 Broadway, ~0.6 km from GZ) were measured on or about 5th, 13th, and 21st October. These last two dates are different from the dates suggesting violent, short-lived fires. That would be expected, of course, considering that 1,3-DPP would probably not survive such extreme fire events but would be converted into other products. In early October, however, full-scale clean-up operations had just begun at GZ, and 1,3-DPP might have been released at more locations in the pile, in some cases through physical or chemical means.
As for the effects of heat, the products of the pyrolysis of 1,3-DPP at 375°C are styrene and toluene, in equal amounts (Poutsma and Dyer [FONT=&amp]1982[/FONT]). This can occur directly in the dry composite (Kidder et al. [FONT=&amp]2005[/FONT]). Additionally, high temperature oxidation of toluene is known to produce benzene (Brezinsky et al. [FONT=&amp]1984[/FONT]).
The spikes in VOC detection could also be explained as a result of the rapid combustion of typical materials found within a building structure. If energetic nanocomposite materials, buried within the pile at GZ, were somehow ignited on specific dates (Table [FONT=&amp]1[/FONT]), violent, short-lived, and possibly explosive fires would result. Such fires would have quickly consumed all combustible materials nearby. The combustible materials available, after a month or two of smoldering fires in the pile, might have been more likely to be those that were less likely to have burned completely on earlier dates, like plastics. Later combustion of such plastic materials, in violent but short-lived fires, could explain the spikes in VOCs seen on those dates.
As for Cahill's data, the presence of compounds of sulfur and silicon in the fine PM seems to fit well with this hypothesis. Sulfur is typically an ingredient of aluminothermic materials (e.g. thermate), and silica is often the structural base for energetic nanocomposites. Sulfur might have been released, along with very fine silicon compounds and other species related to energetic nanocomposites, through explosions, violent fires, or other physical disturbances in the pile at GZ.
Along these lines, it is noteworthy that the data from EPA and Cahill show that detection of aluminum, iron, and barium, all of which are common ingredients of thermate-like aluminothermic mixtures (Jones [FONT=&amp]2006[/FONT]), spiked on specific dates. Cahill's data show a very noticeable simultaneous spike for aluminum and iron on 26th October. The EPA data show that, of the 28 days that aluminum was measured in air during 2001, the dates of maximum detection fall on the same dates as that of iron for the top 9 days in each case. Barium shares eight of these top nine daily maxima.
The metals mentioned by Cahill, for which the "anaerobic incineration" mechanism was proposed, might also be explained by further development of this hypothesis. For example, vanadium oxide has been used in energetic nanocomposites (Gash et al. [FONT=&amp]2000[/FONT]) and has been added to hybrid aerogels for the improvement of electrical conductivity, and to silica nanocomposites for the purpose of catalysis (Harreld et al. [FONT=&amp]1998[/FONT]; Luco et al. [FONT=&amp]1995[/FONT]). The EPA data show a maximum detection for vanadium on 19th December, the same date as EPA's maximum detection of iron, and the date of the second highest detection of both barium and aluminum. The highest detection of barium occurred on 7th March, 2002.
Titanium and nickel, other metals detected in unusual quantities by Cahill, have been used in the production of energetic nanocomposites as well (Gash et al. [FONT=&amp]2003[/FONT]). Neither EPA nor Cahill reported specific measurements for titanium, but spikes in the detection of nickel are clear in the EPA data on 11th October, 19th December, and 7th March, 2002.
Further testing of this hypothesis, for the presence of energetic materials at GZ, might focus on dust samples. For example, if aluminothermic mixtures were ignited at the WTC, significant quantities of the oxidized aluminum would have been present in the air and dust. Because EPA and Cahill used elemental analyses only, the fraction of aluminum present as aluminum oxide was not identified. Unfortunately, air samples are not likely to be useful at this late date but specific measurement of aluminum oxide in dust samples can certainly be done. Such measurements may also help to explain other anomalies observed at the WTC, such as the plumes of white ash accompanying very bright flames at the South Tower just before its fall (Jones et al. [FONT=&amp]2008b[/FONT]). Other tests for the remnants of energetic nanocomposites in the WTC dust would be indicative as well.

[FONT=&amp]6 [/FONT]Conclusion

The presence of energetic materials, specifically energetic nanocomposites, at GZ, has the potential to explain much of the unusual environmental data seen at the WTC. Thermite, discussed briefly above, is such a pyrotechnic mixture that cannot be easily extinguished and is a common component of energetic nanocomposites. Unusually high detections of sulfur, silicon, aluminum, copper, nickel, iron, barium, and vanadium might all be explained by physical release of materials from such energetic nanocomposites. Additionally, the detection of 1,3-DPP at the WTC supports this hypothesis. Finally, the spikes in VOCs, detected by EPA on specific dates, are more readily explained as a result of short-lived, violent fires caused by energetic materials.


Notes

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[/FONT]

Demolition Access To The WTC Towers: Part One - Tenants

by KEVIN RYAN

August 9, 2009

See also,
in this series: