Here's a few links, gang, enjoy
http://wardgriffin.com/fire.htm
It is no mystery why the fire has burned for so long. Mangled steel and concrete, plastics from office furniture and equipment, fuels from elevator hydraulics, cars and other sources are all in great supply in the six-story basement area where the two towers collapsed.
Water alone rarely can quench this kind of fire, which will burn as long as there is adequate fuel and oxygen and as long as heat cannot escape, fire experts said.
http://pubs.acs.org/cen/NCW/8142aerosols.html
The fires, which began at over 1,000 °C, gradually cooled, at least on the surface, during September and October 2001. USGS's AVIRIS also measured temperatures when it flew over ground zero on Sept. 16 and 23. On Sept. 16, it picked up more than three dozen hot spots of varying size and temperature, roughly between 500 and 700 °C. By Sept. 23, only two or three of the hot spots remained, and those were sharply reduced in intensity, Clark said.
http://216.109.125.130/search/cache?p=trad...&icp=1&.intl=us
"So what you've got is a smoldering situation," said George Miller,
president of the National Association of State Fire Marshals.
"Judging from my 32 years of experience, this could burn for a long
time."
Exactly how long "a long time" is, no one knows for sure. But fire
engineers and safety experts told the Daily News that the blaze
likely will continue burning for months -- until most of the 1.2
million tons of debris are hauled away.
A fire needs three things to survive: fuel, oxygen and a heat source.
"If you can break that formula in any way, it will go out," said
Marko Bourne, a spokesman for the fire administration of the Federal
Emergency Management Agency. "The problem is how to do that with this
fire."
While the blaze is starved for oxygen, the scalding steel buried
below ground will retain its heat until enough air reaches it or
water douses it, said Don Carson, a hazardous materials expert for
the National Operating Engineers Union.
http://www.geospatial-online.com/geospatia...ail.jsp?id=1325
Thermal. To monitor the fires that burned for weeks within the rubble, EarthData used a thermal sensor flown from 3,000 feet AGL. Figure 5 is a computer composite of an orthophoto map image (horizontally accurate to 53 feet) of the WTC site acquired on September 17, 2001 combined with a thermal image. EarthData generated the color composite overlay using a thermal sensor that is sensitive to infrared radiation rather than light. Thus, it revealed the location of hot spots within the debris field, indicating a strong probability of lingering underground fires.
http://www.gasandoil.com/goc/news/ntn20242.htm
World Trade Centre still burns because of major oil spills
05-12-01 More than 130,000 gallons of oil from transformers and high-voltage lines -- most of it containing low levels of hazardous PCBs -- were lost at the World Trade Centre on Sept. 11 when two downtown Con Edison substations were destroyed. In addition to the Con Ed release, confirmed by company spokesman Mike Clendenin, the Port Authority is unable to account for 50,000 of 70,000 gallons of diesel and fuel oil stored in belowground tanks at the Trade Centre complex to power emergency generators.
As much as 180,000 gallons of flammable oil -- roughly equivalent to 10 times the amount of jet fuel in the two airliners that crashed into the twin towers -- may be feeding the fires that have been burning for more than two months at the site. Con Ed and Port Authority officials say they don't know whether the contaminants seeped into the soil, burned or drained off into the Hudson River. Environmental Protection Agency officials confirmed they are searching for the oil and pumping it out when they find it.
A private environmental data firm hired by the city to report on known hazardous materials at the Trade Centre warned in a letter to federal and state environmental officials that the oil "could be fuelling the onsite fires", a letter from Walter Hang, president of Ithaca, NY-based Toxics Targeting, said.
"That's exactly what's burning," said a Fire Department source. "All that fuel, all those cars that were in parking lots down there, all kinds of stuff."
http://www.firefighting.com/articles/namFu....asp?namID=5071
High-Tech Maps Track Ground Zero's Endless Flames
Several experts consulted by the New York Fire Department have said the fires have burned for so long for several reasons: they cannot be fought directly; they feed off of a huge reserve of combustible materials; and, they are fed in a restricted but regular manner by air currents filtering into the rubble from above.
When the giant cranes at Ground Zero lift off carbonized and bent steel beams that once formed the twin towers, sometimes so hot they gleam red, they create a flow of air that can rekindle an underground fire.
http://www.nytimes.com/library/national/index_TOPO.html
Detailed maps
http://www.newscientist.com/article.ns?id=dn1634
When untreated water meets a greasy or painted surface it forms beads. "But FEF is a blend of surfactants that reduce the surface tension of water," explains Robert Tinsley of Pyrocool.
This makes the water in the foam much "wetter" so that it flows over and coats surfaces.. Paul Berger, a chemist at Pyrocool told New Scientist: "Pyrocool-treated water is able to develop a high surface area relative to total mass, permitting a very rapid heat transfer from the hot object to the water."
The use of FEF foam began on 28 September, with thousands of gallons being pumped into the rubble. One target was the large Freon tanks that had served the WTC air-conditioning system and might have exploded. Blaich told New Scientist: "The foam also extinguished the fires in World Trade Center No 7, the wreckage of a 40-story office tower."
Another strategy that can be used to put out difficult fires is pumping an enclosed area full of the inert gas nitrogen, starving the fire of oxygen. But Ground Zero is thought to be too large and porous for this to be effective.
Rescue operation
Tinsley says there are several reasons for the longevity of the fire: "First, this is not a typical fire by any means. The combustible debris is mixed with twisted steel in a mass that covers 17 acres, and may be 50 metres deep. This is the one all future fire scenes will be measured against."
The other reasons are human. For nearly three weeks, Tinsley says, city officials insisted that work at Ground Zero was a rescue operation, meaning it would have been inappropriate to flood the rubble with water. As a result, he says, "the fires had a 17-day head start when we arrived."
And there is the issue of human remains. These are still being found and removed and, since the fires are not threatening any property or lives, they are being allowed to burn on.
http://www.osha.gov/Publications/OSHA3189/osha3189.html
The parking garage under the WTC held nearly 2,000 automobiles, each tank holding an estimated five gallons of gasoline. When recovery workers reached the cars, they found that some had exploded and burned while others remained intact.
HOT STEEL
Another danger involved the high temperature of twisted steel pulled from the rubble. Underground fires burned at temperatures up to 2,000 degrees. As the huge cranes pulled steel beams from the pile, safety experts worried about the effects of the extreme heat on the crane rigging and the hazards of contact with the hot steel. And they were concerned that applying water to cool the steel could cause a steam explosion that would propel nearby objects with deadly force. Special expertise was needed. OSHA called in Mohammad Ayub and Scott Jin, structural engineers from its national office, to assess the situation. They recommended a special handling procedure, including the use of specialized rigging and instruments to reduce the hazards.
http://www.epa.gov/epaoswer/osw/meeting/pdf02/kahnp.pdf
Cahill arrived at Ground Zero weeks after the reports of molten metal at the scene,
but his extensive research on why the rubble piles smoldered so long was of interest to controlled-demolition theorists, who believed molten steel in the bottom of the piles provided the heat source. Such was not the case, Cahill said. Instead, fuel oil from the WTC’s generators seeped into the ground, ignited and slowly consumed the debris stacked on top of it. As the piles were peeled open, oxygen stoked the underground fire, which burned for weeks.
http://www.newsreview.com/sacramento/Content?oid=oid:65238
