The 6 problem reactors which have gotten all of the press are located within the Fukushima Daiichi complex.
However, the same nuclear power plant operator that runs the Daiichi complex - Tepco - runs a separate nuclear complex 7 miles away, called Fukushima Daini. There are 4 reactors located at the Daini complex.
On March 12th, Tepco reported:
Unit 1
- At 8:19am, there was an alarm indicating that one of the control rods
was not properly inserted, however, at 10:43am the alarm was automatically
called off. Other control rods has been confirmed that they are fully
inserted (reactor is in subcritical status)
***
- At 6:08PM, we announced the increase in reactor containment vessel
pressure, assumed to be due to leakage of reactor coolant. However, we
do not believe there is leakage of reactor coolant in the containment
vessel at this moment.
- At 5:22AM, the temperature of the suppression chamber exceeded 100
degrees. As the reactor pressure suppression function was lost, at 5:22AM,
it was determined that a specific incident stipulated in article 15,
clause 1 has occurred.
(Article 15, Clause 1 of Japan's Act on Special Measures Concerning Nuclear Emergency Preparedness simply provides that there are elevated radiation levels or that "an event specified by a Cabinet Order as an event that indicates the occurrence of a nuclear emergency situation has occurred.")
Tokyo Electric Power Co Inc said on Monday it had detected a rise in radiation levels at its Fukushima Daini nuclear power plant.
A company spokesman said that the cooling process at the plant has been working properly and that the rise was probably due to radiation leak at the nearby Fukushima Daiichi nuclear complex, where cooling functions were damaged by Friday's massive earthquake and tsunami.
Today, Tepco announced that smoke was seen rising from Daini reactor number 1:
Smoke was spotted at another nuclear plant in northeastern Japan on Wednesday, Tokyo Electric Power Co. said.
The company said smoke was detected in the turbine building of reactor No. 1 at the Fukushima Daini nuclear power plant around 6 p.m. (5 a.m. ET).
Smoke could no longer be seen by around 7 p.m. (6 a.m. ET), a company spokesman told reporters.