The whole world witnessed in real time since last Friday, March 11, thanks to the advanced level of Information and Communication Technology (ICT), the terrible devastation that has befallen the “Land of the Rising Sun”. The magnitude 8.9 to 9.0 earthquake that occurred 130 km east of Sendai, Honshu, and the subsequent tsunami that it generated, has in an a span of about 30 minutes, caused the loss of thousands of lives and destruction that would cost billions of dollars to fix. I am saddened by this tragic event, particularly the loss of lives and my sympathy goes to the people of Japan, especially to those who lost loves ones. I pray that they will all find the strength to cope with their loss, and hope that the Philippines would be able to participate, as soon as possible, in the international effort to help and assist, in their time of need, this country that has given us not only aid but also job opportunities to tens of thousands of Filipinos.
Earthquakes and tsunamis are not foreign to the Japanese, for they are well aware that their country is located on a “subduction zone” (an area on earth where two tectonic plates move towards one another and one slides under the other), being surrounded in the north, east and west by trenches and troughs. The word tsunami also came from them. This is to say that they are well aware of the reality and the consequent dangers of these two natural occurrences and have prepared for it so that its disastrous effects can be mitigated. They are considered the most prepared nation in the world when it comes to earthquakes and tsunamis.
But despite their preparations, consisting of scaled up building construction codes and a national infrastructure for addressing these emergencies (which includes warning and response systems), they were caught off guard - although it can rightfully be argued that without their preparations the damage would have been far worst. Unfortunately their reputation for discipline and rigid compliance, particularly with engineering and other technical requirements, was not enough to spare them from the tragedy that occurred.
The Philippines should strive to learn from what has recently occurred in Japan for like her, we are located on a “subduction zone”, sandwiched practically in its entire length by the Manila, Negros, Sulu and Cotabato Trenches (on the west) and the East Luzon Trough and Philippine Trench (on the east). Any major underwater earthquake in these faults would create a tsunami that can hit land at the speed and force that was experienced last March 11 in north-eastern Japan (In addition, potential danger is also posed by faults that criss-cross practically most of the land). If that kind of destruction can happen to a prepared Japan, I dread the outcome that would befall an unprepared Philippines.
Our government agency tasked with mitigating the effects of disasters should seriously look into the creation and installation of an operational system (if not yet existing) that would address earthquake and tsunami emergency situations with the objective of minimizing both loss of life and damage to property, down to the barangay level. They can very well tie up and collaborate with NGOs and other social organizations that can act as force multipliers for this effort.
But the Japanese misfortune did not end with the devastating effects of the earthquake and tsunami. They unfortunately have to contend with a third brewing tragedy which, if it happens, would have more far reaching repercussions - the meltdown of at least two nuclear reactors.
Eleven of Japan’s 55 nuclear reactors (located in 17 nuclear power plant or NPP complexes nationwide) tripped automatically when what is now termed as the “Sendai earthquake” occurred (Six of these 11 are located in the Fukushima Dai-ichi NPP, four in the Fukushima Daini NPP and one in the Onagawa NPP). Although the emergency shutdown was successful, there was still what is called the “decay heat” that needed to be extracted from the core by means of a cooling system that needs to continuously supply cold water in the core to cool (or cover) the fuel rods over a number of days to achieve what they termed a cold shut down. This had to be done because otherwise the water in the core will boil over and cause the exposed fuel rods to overheat. This situation could bring about a chain of problems that may be difficult to address and could result to a meltdown.
Based on news and web reports, the extraction of decay heat posed a problem for the Fukushima Reactor Nos. 1, 2 and 3 because as a result of the shutdown, the external power to run the cooling system (composed of pumps, valves & controls) that would continuously pump cooling water into the core was no longer available. Due to this, the staff had to rely on the internal standby power, through diesel generators, which because of the flooding, conked out after only about an hour of operation. Backup batteries were reportedly used afterwards but they lasted only for eight hours so eventually the supply of cooling water fell short of what was required which caused the upper parts of the fuel rods to be exposed to air and overheat. Under this situation, the pressure build-up in the core’s primary containment continued (consequently the overheating zirconium fuel rod casing - - possibly reaching 2,200 degrees F - reacted with steam, or water, to form zirconium oxide and hydrogen gas). This prompted the operators to relieve the pressure from the primary containment, to prevent it from exploding, by venting the steam into the atmosphere. The problem was that the steam vented directly from the core had hydrogen gas which reacted with the oxygen in the air and caused the explosions observed from Reactor Nos. 1 and 3. The explosions damaged the upper cladding of the reactors’ structures. As a last effort, the operators resorted to pumping salt water from the sea, together with Boron (which can disrupt chain reaction), into the core of all the three nuclear reactors to cool it down and stabilize its pressure. This futile move, it is said, will no longer make the reactors useable.
The effort to cool the reactors is still ongoing and it may take a number of days before the final result of the effort can be seen. However, the venting move has also created a secondary problem as it has increased the amount of radiation in the area to alarming levels, prompting the government to evacuate about 180,000 persons located within a 20 km radius of the nuclear plant. Some of those evacuated were found to have been contaminated with higher than acceptable levels of radiation. Tests also showed the presence of Cesium in the immediate vicinity of the power plant which is indicative of the possible melting of parts of the fuel rod or core (Cesium is generated during a chain reaction and tends to migrate towards the fuel rod casing and will be released only if the casing is breached or melted).
Again, I pray that a meltdown does not occur. However, we should be looking with special interest in what is happening with the Fukushima Dai-ichi Complex’s nuclear reactors No.1 (BWR, ~439MW, GE, ~41 yrs old), No.2 (BWR, ~760MW, GE, ~37 yrs old) and No.3 (BWR, ~760MW, Toshiba, ~35 yrs old), given the ongoing debate regarding adopting nuclear power plants, particularly the BNPP (LWR or BWR, ~620MW, Westinghouse, ~27 yrs old), as a means of electric power generation. The insights that can be gained from this development may be the eye-opener that would bring about a final position regarding this issue. A position that, only through a widespread and intelligent national debate, would give regard, not to the vested interest of a few, but to those of the majority; not only to the country’s stakeholders of today, but more importantly to the country’s stakeholders of the future.
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