Archived Messages from 8/12/12 to 1/6/13, listed in reverse chronological order: Update: 1/6/13, 10:10 A.M. - Radiation Alerts from Hawaii
The same station operator has triggered radiation alerts in past months, and viewers can read about those in the Archived messages linked above. As is our policy on the Radiation Network, if we believe elevated readings from a station to be genuine, we typically "let it run", but at the same time, station operators are responsible for communicating over the network so that we can try to explain alert level readings. Without such interaction, the network reserves the right to disable such a station for the time being. Update: 11/24/12, 9:00 A.M. - "There's something out there..." in the Texas Panhandle
As soon as the Alert was broadcast, our members immediately engaged the integrated Chat forum on the Radiation Network to explore the reason for the high readings. So first, a number of facts. The WTX station has been monitoring steadily since April of 2012. He operates the high count rate, ultra-sensitive Inspector Geiger counter, and sits it in a stand on the second floor of his house. There was no logistical change to the Inspector at the time the readings began elevating. A battery change was made 2 weeks ago, and the Inspector had been running perfectly. The Geiger counter readings themselves mirrored the counts being registered by the software. The subsiding of readings to normal after the alert indicates the Geiger counter did not malfunction, at least for good. The operator owns some radioactive samples, but claims they were secured away. There was no rain or wind at the time, the jet stream was flowing far to the north, and no local earthquakes of significance that might release Radon, no solar flares of note (which probably wouldn't be localized, anyway), and no NRC events in the area. The operator knows of no radioactive persons or pets nearby that were undergoing medical treatment. Company at the neighbor's was leaving 20 minutes earlier, but had apparently been there before the incident. Anyway, the operator believes there were no persons or pets outdoors at the time, and the street was clear. The highway is over 2 miles away. So where does that leave us? Providing the departing neighbors were not "radioactive", I would point out in case it might be relevant, that the Pantex plant is located 25 miles to the southwest. For those unaware, Pantex is a division of Babcock and Wilcox, and operates a nuclear weapons assembly and disassembly facility outside Amarillo. Here is a link: http://www.pantex.com/Pages/default.aspx Follow-Up: Radon daughters or Iodine-135? The Alabama station operator points out that it is Iodine-135, also a product of nuclear fission, that has a short half-life, only 6.6 hours, thus placing it in the running for the isotope behind the fast decay rate on his rain sample. Without taking a position on this, I put it out there to generate discussion. Update: 11/13/12, 9:10 A.M. - Radiation Sampling from Alabama
This Alabama station is part of a group conducting multiple samplings downwind of Browns Ferry Nuclear Plant, and we are very happy to welcome their contribution to the Radiation Network. In the operator's thinking, radiation brought down by precipitation becomes concentrated on the ground, therefore the reason behind the logistics of yesterday's test. He also scanned a wipe of wet dirt off his truck during the rain, and reports a very high reading - over 1,500 CPM, but which reading subsided to about 70 CPM during a follow-up scan 3 hours later. The sharp drop in readings point to a rapid decay rate of the offending isotope, which in my book, in turn points to Radon washout, although the station operator added that Iodine (presumably 131, the nuclear fission byproduct) also has a fast decay rate. I looked it up, though, I-131 half life is 8 days, which is longer than that of the Radon daughter products, I believe, that are associated with Radon washout. For those interested in the science of what we are all doing, notice how the Alabama station correctly followed these steps:
This series of steps, of course, is what I call the "poor man's radioactive isotope identifier test", that can be done with the same Geiger counter that is used to find the original sample radioactive. The reading from the first radiation scan is interesting, but tells only half the picture. So when you see an Internet video out there posting 1,000 CPM reading of rainfall using their Geiger counter, ignore it unless the operator also broadcasts the reading from the follow-up radiation scan. Update: 10/25/12, 10:30 A.M. - Radiation Alert in Wisconsin
For context, Frederic is monitoring with the ultra-sensitive Inspector EXP. This model uses an external probe which he has set up outdoors. See the Update below dated 6/1912. Frederic is capturing precipitation samples which are turning up as elevated in radiation as the current environment itself, so after the weather system passes, and his environmental radiation levels drop to a normal 45 CPM or so, he will scan the same rainwater samples to see if the reading remains elevated as in the initial scan, or whether they have subsided.
Postscript: 10/23/12, 11:00 A.M. - As to the Grand Rapids, MN
alert from yesterday, the station operator reports his PRM-9000 was
sitting on the ledge near the wall in his bedroom within his log home - the
pancake GM tube facing inward. One of our network members retrieved the
Jet Stream forecast. Notice how the southern edge of the stream
passed directly above Grand Rapids, Minnesota when the Radiation Alert
occurred. We've seen this combination before with other stations on our network - a sensitive Geiger counter, even located indoors, detecting rising radiation levels during a passing weather pattern or jet stream. I would add that for such a detection to be made by an indoor Geiger counter, the radiation would probably have to be Gamma, because Beta and Alpha particles are too weak to penetrate the walls of most structures, unless they could enter through a ventilation system or other portal. So how do we know what the source of the radiation is? Hypothetically, the cause would typically be from either "Radon washout" or something more sinister like man-made nuclear reactor by-products. In a situation as this, the station operator could capture an associated rainwater sample or a fresh air filter intake, and subject them to the "poor man's radioactive isotope identifier" test. See the Update from 3/18/12 for details on that The station operator added yesterday, "There also is some reports out that Reactor 4 in Japan has fuel rods that have caught on fire and radiation is going off the charts within 50 miles of Fukushima, but that is not confirmed yet as truth, and if that happened today, there is no way it could have gotten into the jet stream that fast and made it over here."
The Radiation Network has a contributing Monitoring Station located in Grand Rapids, Minnesota that is triggering Radiation Alerts as I write this, since about 1:00 P.M. local time. Until we receive feedback from the station operator, we have no reason to believe this is not a genuine detection of elevated radiation levels, and so as with our policy, this will be allowed to play out for the time being. The graph shows steadily rising radiation from a normal background level of about 40 CPM, eventually exceeding the 100 CPM alert level on our network. We know Grand Rapids operates the PRM-9000 Geiger counter which is built around the same ultra-sensitive pancake style Geiger-Mueller tube as in the Inspector line of instruments. Without yet knowing the source or nature of the Grand Rapids radiation, I can say that particular model of GM tube has demonstrated at other times and across other monitoring stations how sensitive it is to passing radioactive weather patterns, even from an indoor monitoring posture. When we obtain more information, we will provide a follow-up report. Update: 10/20/12, 1:00 P.M. - Radiation Alert in Oregon
The station operator had this input, "It was raining outside. My meter is on my window looking out and up. Then all of the sudden I get higher numbers up to 1,187 count. For about 2 minutes, it was crazy and then started to wind down." The table of minute by minute radiation counts below does look like a genuine pattern of readings from a passing radioactive source. But from a later discussion with the operator, he believes the cause is a malfunction of his detector, and he intends to upgrade to a proven model like the Inspector line of instruments. It should be noted that there were no corroborating readings from our other stations in Oregon and Washington. It is true that this GMQ-200 model of Geiger counter is a relatively new and untested detector on our Radiation Network, so maybe there is an issue of data integrity out of the data port of the device?
Update: 9/30/12, 11:45 A.M. - Three Mile Island Driving Tour Some of you may know there was a "steam release" at the Three Mile Island (TMI) Nuclear Power Plant on Sept. 20. The plant operator said there was first an automatic shutdown for an unknown reason, triggering the release of steam which normally runs the turbines, but upon the shutdown needed somewhere else to go. He added that there were "no detectable levels of radiation in the steam".
Three Mile Island is located south of Harrisburg, PA, and is so named because it
is situated on an island in the middle of the Susquehanna River. Study the map
at right, and particularly the red lined GPS trail.
During the tour, his Inspector was available to outside air through an open car
window. Meanwhile,
the software was graphing the radiation counts (at left) for all of us to
see in real time, while
the GPS panel continually tracked his position. The image at right
depicts the end of the driving survey. Bottom line - according to a minute by minute data log during that part of the mobile monitoring survey closest to the plant, from about 12:50 to 1:00 on the east side, and 1:35 to 1:55 on the west side, there was no discernable and sustained elevated radiation level detected above normal background. The station operator indicated access to the island itself was restricted - "check points with personnel and white vans". However, he did plan to collect soil samples in the vicinity for later analysis. This experience reminds me - after the famous TMI accident in 1979, a grass roots monitoring network was set up around the perimeter of the plant. That system was engineered by International Medcom, manufacturer of the Radalert and Inspector Alert Geiger counters, and for its day, served a valuable community service. While that could be considered a precursor for the "Radiation Network", today we have Internet connected personal computers which, through the underlying software, makes possible a fully automated monitoring system in real time (no manual posting of data required), readily available to contributors and participants, along with an early warning feature. Update: 8/26/12, 1:35 P.M. - False Alerts There were a couple of false alerts recently. On Tuesday evening, August 21st, a station located in the Salt Lake Valley of Utah recorded about 500 CPM for a couple of minutes, following sustained readings of 0 CPM. This was caused by an equipment malfunction. The station operator explained, "Sorry, my apologies. My system has been giving an occasional high reading and finally my GM tube died. This extremely high reading was the tube going out." The second false alert emanated from a station located in Terre Haute, Indiana during the late evening of Friday, August 24th. Until the station operator unplugged from the Radiation Network, his readings approximated 200,000 CPM for a 5 minute period. From experience, readings this high almost always derive from some sort of glitch, because they would otherwise require extremely close proximity to a sizable quantity of high grade uranium ore, or to be in some proximity to a nuclear detonation, neither of which were the case. The Indiana station is operating the standard tubed PRM-8000, one of the few models to offer true data logging, and the operator explained that the battery had died (after running since early June), and in replacing the battery, the instrument somehow reset to uploading historically logged data. However, the Radiation Network software interpreted that output as real time, treating the potentially days or weeks of historical data as all having occurred in a single minute - thus the very high reading. That's the theory anyway, and I was able to somewhat duplicate the anomaly using my own PRM-8000. This definitely falls under the category of a freak incident. Sorry for the false alert. We'll see how we might modify the software to prevent this kind of recurrence, without negating its early warning feature. Having said that, it would be prudent for all station operators to unplug from the Radiation Network while performing maintenance on your detectors. Update: 8/12/12, 7:25 A.M. - Breaking News! - Fukushima triggers run on Plastic Bags :-)
I have seen this phenomena many times since Fukushima, where placing the Geiger counter inside a plastic bag causes an over "accumulation" of radiation counts. I don't know why this happens. My personal theory (although not a very good one) is that radon gas has a chance to build up in the unventilated space of a bag, in the same way that radiation readings are often elevated in a radon infested, sealed basement. I'm guessing that sometime after Fukushima, a novice Geiger counter operator, perhaps in Japan, decided to slip his detector inside a plastic bag, maybe to protect against potential contamination, and others saw this and picked up what I consider to be a very bad habit. To me, about the only valid reason to bag up your Geiger counter is to avoid water damage while taking a momentary outdoor reading in the rain. The drawback is that the plastic will shield any detectable alpha radiation which a surveyor would normally want to include. Nor would I place my Geiger counter on the ground, or at least not inside a bag while on the ground. When taking readings outdoors, and to guard against airborne contamination that could precipitate downward, orient your Geiger counter so that any end or side window faces downward itself. Who knows how many false detections and alerts this bad, baggy practice has caused? So the moral of the story is, "If you don't want an artificial reading, then don't create an artificial environment!"
Thanks again for your support. Tim Flanegin Back to the Radiation Network Click here to go to Archived Messages |