* Radiation echoes Three Mile Island, but no meltdown yet *
Stricken reactor dates from 1970s, newer models "safer" By
Gerard Wynn LONDON, March 12 (Reuters) - The radiation leak in
Japan immediately recalls memories of accidents at the Chernobyl
and Three Mile Island power stations, and how it unfolds will be
a critical test for international acceptance of nuclear energy.
The Fukushima incident, brought on by the biggest earthquake
ever recorded in Japan, took a turn for the worse on Saturday
after a blast blew the roof off the facility. There are direct
comparisons with the 1979 disaster at Three Mile Island in the
United States -- in both cases a cooling fault led to a build up
of pressure in the radioactive core and resulted in a relatively
small radiation leak. Both use water to control the temperature
as uranium degrades in a nuclear chain reaction at the reactors'
core, creating steam which drives a turbine to generate
electricity. The stricken Japanese reactor north of Tokyo has
little parallel, howev