More has happened and Fukushima, less reporting has occurred. The TEPCO reactors still have not had adequate cooling for weeks on end. Radiation levels have not been low enough for workers to really get close enough to see what exactly is going on, but the US press has quieted down on the topic. On Sunday I read an article that stated that the radiation levels in the exclusion zone at Fukushima where 400% higher than Chernobyl. A shocking revelation if one does not question the article. First of all I will mention that the reactor at Chernobyl released 10 times the amount of radioactivity that the four reactors at Fukishima and their fuel ponds have released so far. Chernobyl's core was actually exposed to open air! Chernobyl had a lead cooled reactor, with graphite moderator control rods, so they actually burned too. The reactor exploded, none of the reactors at the Daiichi power plant have, all though they have vented tritium gas that blew up the containment buildings. Chernobyl had no concrete containment buildings. Why recap, Chernobyl was 25 years ago. The article I read was comparing the current levels of radiation at Fukushima to those of current Chernobyl. Over the two and one half decades since the explosion radioactive material has decayed, the wind, water and soil have diluted the radioactive materials. Currently there are many places on earth that are naturally more radioactive than Chernobyl. The beaches of the French Riviera, Some beaches in India, and Ramsar Iran all have natural background radiation levels that are higher than Chernobyl is currently. The article is clearly poorly researched. My best guess, if you measured the background rates of Chernobyl 25 years ago, after the accident, they would be just as high if not higher than Fukushima. Also, the big question is 4 X What? 4 X 2 microRoentgens per hour is significant, but probably attributed to natural sources, 4 times 2 milliRoentgens per hour is very significant, and 4 times 2 Roentgens per hour is scary. My humble opinion, post the measurements without comparisons, or if they must compare, compare the levels to something the average person can relate to, like a dental X-Ray, a chest X-Ray, or a CAT Scan. A good Example, 10 Roentgens per hour would be like getting 10 full body CAT scans in one hour. The average person can understand that that would not be a good thing. There is a little more to the exposure rates at Fukushima than that, obviously there are issues of air, water and foodstuffs that are contaminated by radioactive dust, liquids and gasses, and each isotope involved can act on particular organs. A good example, Iodine 131 and the Thyroid, but it only has a halflife of 8 days. Cesium 137 has a halflife of about 31 years, and is absorbed in muscle. What really has surprised me is no Mention of Strontium 90? Strontium 90 acts like calcium, and ends up in ones bones. However, most people understand that chemical exposure is bad, so if you are wearing protective gear, you should be safe, unless you ingest the isotopes.
There is still another major leak that hasn't been found. 10,000 gallons of radioactive water has been dumped in the ocean (however it should dilute very rapidly). TEPCO states two reactors, 5 and 6, not involved may be salvageable, yet the Japanese government says they are scrap. Oh, and I forgot to mention, the disaster has been upgraded to a Level 7 on the IAEC's one through seven scale, which means it is as bad or comparable to Chernobyl. There has also been some speculation regarding U.S. GE engineers at the plant and the use of MOX (Mixed Oxide Fuels that have Plutonium in them). I do not find that unusual considering the reactors where designed by GE in the United States. Also MOX is an accepted nuclear fuel in these days of nuclear disarmament, a noble use for an element made for such a nefarious use. Besides, none of that caused the disaster, remember it was a magnitude 9 earthquake followed by a tsunami, which took out diesel generators and swept away backup generator fuel tanks after the reactors scrammed. By the way, there where borated water supplies on site, however heat is needed to allow the boron compounds to be mixed with water, and pumped into the reactors. No diesel generators, no pumps, no hot water to keep the boron hot, no way to get it into the reactor where it belongs after a hard shut down.
This leaves me to my numbers for 4 10 2011, 4 11 2011 and 4 12 2011:
Well, that is it for today! Situation Normal, at least in Yukon Oklahoma.
PM1703m Rad Pager = 8 microRoentgens per hour, Geiger Counter Wristwatch .12 microSieverts per hour