Frantic bid to contain damage at stricken nuclear plant
...One of the problems is that workers dare not edge too close because of high radiation levels at the site.
The outer building concrete layer of the No. 1 reactor was damaged Saturday by a hydrogen explosion triggered by the
Great East Japan Earthquake that hit the day before. That, however, did not trigger a major crisis.
Officials said the situation in the building remained comparatively stable.
When asked why the No. 1 reactor was targeted for intense water-spraying operations, Chief Cabinet Secretary Yukio Edano said at a Friday morning news conference, "While the situation is not as serious as the No. 3 and No. 4 reactors, it will be important to increase the water in the pools (storing spent nuclear fuel rods) at each reactor as part of efforts to cool the rods." ...
http://www.asahi.com/english/TKY201103180197.html