福島原発、専門家ら「3つの懸念」 燃料棒激しく損傷 (1/3ページ) 2011/3/30 6:21

via 福島原発、専門家ら「3つの懸念」 燃料棒激しく損傷  :日本経済新聞.

From the Nikkei: 3 causes for concern at Fukushima (my rough translation).

  1. Insufficient water in the No. 1 reactor, both now and in the early stages of the crisis has probably led to melting of the fuel rods. Pressure readings from the reactor suggest that there is very little probability of radiation leak from the pressure vessel, however.
  2. No. 2 reactor: “We cannot rule out the possibility that more than half of the fuel rods have melted”. Pressure seems to be low and it is possible that the pressure-meters are not functioning properly, making data-gathering difficult. The temperature of the pressure vessel also rose to 200 degrees C on March 29. The situation is still unstable. No. 3 reactor. Damage to the fuel rods in this reactor is thought to be less than in reactors 1 and 2, and the temperature is stable. However, contaminated water has been found in the turbine building, with a reading of 750 mSv/hr.
  3. Contaminated water in the lower (underground) part of the turbine buildings must urgently be removed. Until this is done, workers cannot get close to the pumps and the electrical wiring to restart the cooling system. See the image here of plans to move the contaminated water.