Notwithstanding their hedging about continuing to look at all angles, the authorities yesterday virtually ruled out a bomb blast in the Glorietta 2 incident. For NW, the absence of a blast crater or any other signs of shear and gashes on the equipment and walls of the basement is a sufficient condition to discard the bomb hypothesis. The sample testing positive for RDX is irrelevant, although doubting Juans and Juanas don't think so.
Crude but fairly informative and convincing presentations were issued by the PNP - Inter-agency anti-arson task force (IATF) Thunderbolt to the media here and here. There are diagrams, charts, photographs (many without labels and captions) and in sum the presentations are much more than I expected from our police, whose efforts must be recognized. The only spoilers are the faces, in news clips, of security adviser Norberto Gonzales, DILG secretary Ronaldo Puno, and palace mouth Ignacio Bunye, shameless clowns who had engaged in earlier fear-mongering.
Ayala Land casts doubt on theory
At noon yesterday, Ayala Land president presented an enumeration of facts to the press (and posted in their website at my request), tending to cast doubt on the gas explosion hypothesis. ABS-CBN chose to spin the story as Ayala Land Rejects PNP industrial blast theory which is a reasonable interpretation. The enumeration was reportedly finished only Tuesday night and shared with the authorities only yesterday morning. It appears that these so-called facts do not have much relevance to the preliminary findings. Here's a list of the facts Ayala presented:
GLORIETTA 2 BASEMENTThe major element casting doubt on the gas explosion theory is the claim in item 7, which tends to show that there could not have been any significant methane generated by the sump pits, and the claim in the conference that there was nothing out of the ordinary reported by maintenance personnel in regard to the waste water system (the two sump pits and corresponding pumps). However, a maintenance man interviewed by police belies the latter claim. In regard to the amount of methane present, it depends on how much waste had accumulated contrary to the claim of a 24-hour maximum residence time. Also, it is possible that gas could have come from the sewer lines to which the pumps were connected (backflow) and this would have provided enough methane.
1. Basement dimensions: 178 sqm floor area; approx. ceiling height: 2.28m
2. Diesel fuel tank: Last used in June during last power outage; capacity: approx. 14,000 liters; estimated content on day of incident: 6,000 liters; the flash point of diesel contained is 72 degrees Celsius and auto ignition temperature is 220 degrees Celsius. There are no maintenance reports or observations by maintenance personnel of any aberrations to the diesel tank.
3. Fuel transfer pump: transfers diesel fuel from storage tank at basement 2 to day tank at the roof deck.
4. Ventilation: basement is ventilated by air entering the approx. 2.4m x 2.4m opening at stairwell connected to delivery bay area
5. Ambient room temperature: estimated range from 28 to 30 degrees Celsius
6. Grease trap: separates grease from wastewater entering the sump pit; maintained daily for one hour together with cleaning of basement.
7. Sump pits (there are two types of sump pit):
a. Kitchen sump pit (approx .1.5m x 1.5m x 2m): Wastewater from kitchens of five restaurants in Glorietta 2 enters the sump pit. The grease trap separates the grease from the wastewater (grease is extracted daily, every morning). A pump in kitchen sump pit pumps out wastewater to the main city sewer line automatically (there is a standby sump pump).
b. Waste sump pit (approx. 1.5m x 1.5m x 2m): Wastewater from toilets in a portion of Glorietta 2 is dumped into sump pit (21 water closets; 20 lavatories; 8 urinals). Due to the nature of customer use of toilets in restaurants, waste is seldom solid and mostly liquid (per our sewage expert opinion approx. 98% liquid). Wastewater enters sump pit and is pumped out to street sewer by a sump pump (there is a standby sump pump). Therefore, there is constant flow of mainly liquid wastewater from the toilets into the sump pit and on to the city sewer. Wastewater entering the sump pit stays in the sump pit for less than 24 hours. The usual decomposition process brought about by large amounts of solid matter in house septic tanks does not occur in this commercial sump pit.
What can we make of the diesel tank and the role of the fuel in the explosion? The photos in the presentation show a rupture in the lateral joints of, and a hole in the steel plate covering. There appear to be no signs of soot anywhere. The diesel flash point seems irrelevant here, this parameter indicating the lowest temperature which generates enough vapor which, alone, can be ignited, but at which combustion stops if the ignition source is withdrawn. At temperatures below flash point, there is still some vaporization, and if the tank had a leak (not evidenced by police photos), these vapors would have escaped and mixed with the more volatile methane. The auto-ignition temperature is entirely irrelevant. If the tank had no leak, then, I suspect the methane ignited first, heating the tank, vaporizing the contents very quickly, rupturing the cover. The diesel fumes mix with the methane in part of the explosion. If you look inside the dieseltank you'd see that there is some fuel left (but not yet measured). The explosion could have bled the air dry of oxygen very quickly and/or had snuffing effect.
The claim that maintenance personnel reported no aberration with the diesel tank is also not very useful, since the last time the generators were on was in June.
In any case, what should be the most intellectually satisfying proof of the gas explosion theory would be a computer simulation or real scale model simulation or both.
RDX again
To some, the RDX positive test constitutes a loose end. I suppose the foreign investigators would have tested a sample from the same material (found on the ground floor by an Army man) but could not replicate the result. That should be the end of that. No need to explain further that RDX is also found in other (non-explosive) substances.
In the press conference, no reporters confronted Ayala Land spokesman Alfie Reyes about his earlier televised claim the basement was under the control of the Makati Supermarket operators, which he no longer repeated.
Mr. Ayala said the corporation would do right whatever the final findings. While it is easy for them to purchase reasonable doubt at a reasonable cost in the criminal and civil proceedings that will follow, let's hope he keeps his word.
(Glorietta 2 constitutes a mere 0.34 percent of total Ayala Land revenues).
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