Just in case some of you hadn't heard, workers on Saturday have discovered a crack in a maintenance pit on the edge of the complex which has allowed radiative water (radiated by Iodine-131) to leak out, according to Nishiyama Hidehiko (surname first) of the Nuclear and Industrial Safety Agency.
Apparently the crack was caused bythe 9.0 magnitude earthquake on March 11, 2011 which hit northeast of the Dai-ichi (Big One) nuclear facility located in Fukushima-ken (Fukushima province) and has probably been leaking since then.
Air measurementsabove the radioactive water in the pit contained morethan 1,000 millisieverts per hour of radioactivity, but just 60centimetres away, that figure dropped to 400 millisieverts.
What does that mean? How dangerous is it?
The millisievert (mSv) is a measure of the absorption of radiation bythe human body. The highest reading yesterday was reportedly on theorder of 1000 millisieverts an hour which is about 418 times the average safe dosage for a human in a year. Serious? Yes... but only for those at the nuclear facility.
Keep in mind that only 60 centimetres away (24 inches for the metric challenged Americans - or myself), that high level dropped down to 400 millisieverts - or about 167 times the safe dose for a human in a year.
So distance does play a factor... If you are a kilometre away, it's much less... and if you are outside the safe zone of 30 kilometres away, you are indeed probably safe.
Now... in this case, the radioactive water has been entering the Pacific Ocean. People may worry that the waters are being contaminated. They are. But as in the air, the radiation dissipates quickly in the water. So... even large amounts of radioactive water, will have no effect (or very little effect) on marine life.
TEPCO (Tokyo Electric Power Company) is now pouring concrete into the pit to seal the 20-centimetre crack near reactor No. 2's water intake facility.
“Thiscould be one of the sources of seawater contamination,” Nishiyama notes.“There could be other similar cracks in the area, and we must find themas quickly as possible.” Radioactive Iodine-131 atconcentrations higher than the legal limit was first detected in watersoff the plant more than a week ago. Readings released Saturday showedradiation in seawater had spread to 40 kilometres south of the plant;the concentration of iodine there was twice the legal limit, butofficials stressed it was still well below levels that are dangerous tohuman health.
It wasn't immediately clear whether workerswho have been rushing to bring the reactors under control were exposed - but there have been several incidents of the FUKUSHIMA 50 being burned by radioactive water while trying to get the facility under control from a near nuclear core meltdown.
People living within 20 kilometres of the plant have been evacuated,and no fishing is taking place in the waters just off the plant.
Because of the evacuations, the plant workers have been the primary people exposed to the radiation leaks. Aworker fell into the ocean Friday while trying to board a bargecarrying water to help cool the plant, the nuclear safety agency saidSaturday. He was immediately plucked from the water and rinsed off, andhe tested negative for skin contamination. He said he did not think hehad swallowed any water, but officials are still waiting for testresults to make sure he was not exposed to unsafe levels of radiation.
Within the Dai-ichi facility, apparently theplant has run out of the nylon protective booties that workers put overtheir shoes.
“We only putsomething like plastic garbage bags you can buy at a convenience storeand sealed them with masking tape,” said an anonymous worker who added that the tsunamicaused by the earthquake littered the ground with dead fish that remained scattered throughoutthe plant, attracting birds.
Andrew Joseph
Garbage bags?! No wait... it says "something LIKE plastic garbage bags". Still... yeesh!
Apparently the crack was caused bythe 9.0 magnitude earthquake on March 11, 2011 which hit northeast of the Dai-ichi (Big One) nuclear facility located in Fukushima-ken (Fukushima province) and has probably been leaking since then.
Air measurementsabove the radioactive water in the pit contained morethan 1,000 millisieverts per hour of radioactivity, but just 60centimetres away, that figure dropped to 400 millisieverts.
What does that mean? How dangerous is it?
The millisievert (mSv) is a measure of the absorption of radiation bythe human body. The highest reading yesterday was reportedly on theorder of 1000 millisieverts an hour which is about 418 times the average safe dosage for a human in a year. Serious? Yes... but only for those at the nuclear facility.
Keep in mind that only 60 centimetres away (24 inches for the metric challenged Americans - or myself), that high level dropped down to 400 millisieverts - or about 167 times the safe dose for a human in a year.
So distance does play a factor... If you are a kilometre away, it's much less... and if you are outside the safe zone of 30 kilometres away, you are indeed probably safe.
Now... in this case, the radioactive water has been entering the Pacific Ocean. People may worry that the waters are being contaminated. They are. But as in the air, the radiation dissipates quickly in the water. So... even large amounts of radioactive water, will have no effect (or very little effect) on marine life.
TEPCO (Tokyo Electric Power Company) is now pouring concrete into the pit to seal the 20-centimetre crack near reactor No. 2's water intake facility.
“Thiscould be one of the sources of seawater contamination,” Nishiyama notes.“There could be other similar cracks in the area, and we must find themas quickly as possible.” Radioactive Iodine-131 atconcentrations higher than the legal limit was first detected in watersoff the plant more than a week ago. Readings released Saturday showedradiation in seawater had spread to 40 kilometres south of the plant;the concentration of iodine there was twice the legal limit, butofficials stressed it was still well below levels that are dangerous tohuman health.
It wasn't immediately clear whether workerswho have been rushing to bring the reactors under control were exposed - but there have been several incidents of the FUKUSHIMA 50 being burned by radioactive water while trying to get the facility under control from a near nuclear core meltdown.
People living within 20 kilometres of the plant have been evacuated,and no fishing is taking place in the waters just off the plant.
Because of the evacuations, the plant workers have been the primary people exposed to the radiation leaks. Aworker fell into the ocean Friday while trying to board a bargecarrying water to help cool the plant, the nuclear safety agency saidSaturday. He was immediately plucked from the water and rinsed off, andhe tested negative for skin contamination. He said he did not think hehad swallowed any water, but officials are still waiting for testresults to make sure he was not exposed to unsafe levels of radiation.
Within the Dai-ichi facility, apparently theplant has run out of the nylon protective booties that workers put overtheir shoes.
“We only putsomething like plastic garbage bags you can buy at a convenience storeand sealed them with masking tape,” said an anonymous worker who added that the tsunamicaused by the earthquake littered the ground with dead fish that remained scattered throughoutthe plant, attracting birds.
Andrew Joseph
Garbage bags?! No wait... it says "something LIKE plastic garbage bags". Still... yeesh!
