Current EPA RadNet Query findings for Los Angeles, California: 7/28/2011 - 8/4/2011

Thanks for the info and update, Angusmerlin. I have sent an email to the EPA to ask about all of the high peaks in beta counts we've been seeing at several cities across the U.S. recently. I'll let you know when I hear back.

In the meantime, I found some nifty little tools on the EPA's AIRNOW website, http://www.airnow.gov/, for determining air quality for numerous U.S. cities (Note: this is for other pollutants NOT including radiation).

In addition to the current air quality index (AQI) and forecast, they have an animation tool, showing how the forecast changes over the course of a day.

For example, here's San Diego's current AQI and forecast:

http://www.airnow.gov/index.cfm?action=airnow.local_city&cityid=323

(Click on the "AQI Animation" tab and watch how the forecasted pollution from LA and OC seeps down to San Diego throughout the day...) Yuck. :-P

Perhaps the poorer air quality in general has to do with the higher beta counts? We know that it is not just nuclear power plants but other industry (mining, coal plants, etc.) that release radiation (and other pollutants) into our environment.

I remember living near the refineries in the LA Harbor/South Bay region years ago and from time to time, distinctly smelling the pungent toxic pollutants which they would release during the late night hours. So some high beta counts at night could be from all kinds of potential industry releases of pollutants.

There is also an online tool for showing the UV radiation forecast: http://www.cpc.ncep.noaa.gov/products/stratosphere/uv_index/uv_alert.shtml

As you can see, the UV forcast is "above normal" or "well above normal" through much of the country (especially the Southern portions, whether SW, Central 0r SE).

Anyway, these are just my guesses as to why we've seen the elevated beta counts lately...

I'll let you know when I hear back from the EPA about this. Stay tuned...

I would love any guidance about this from our BRAWM team, concerning the EPA RADNET Beta count levels being high for a large number of cities over the past week or so (and some since the end of May). I think many of us lay persons need help in deciphering what these numbers mean.

One blogger who has been following Nebraska and Des Moines, Iowa (neighbors, downwind of Ft. Calhoun) recently, has commented about spikes in beta counts there:

http://majiasblog.blogspot.com/2011/08/des-moines-radiation-levels-augus...

Also, many monitors are often out of service for brief periods of time (Though Richmond, WA has been down for the entire Fukushima event.)

Someone on the blog speculated that these high numbers could be caused by the heat wave, skewing the readings? (These high spikes all seem to been since June).

Anyone have any information on this? Perhaps we can ask an EPA representative to comment here to explain these highs and outages, etc.?

I just found this helpful overview of all the RADNET sites with thumbnails which you can click on to see graphs from each U.S. city that the EPA RADNET monitors:

http://blog.alexanderhiggins.com/2011/04/12/realtime-epa-radnet-japan-nu...

I was concerned (should I be?) to see Harrisonburg, VA, showing the highest of any city's beta counts recently, with a spike at 650 CPM the end of May, and several others high spikes over 700 CPM, the highest going up to nearly 800 CPM around August. Woah...can this be possible? If this is a correct number, should the good people of Harrisonburg, VA be concerned? If it is an anomaly due to a broken monitor, why isn't the EPA stating this on the RADNET website?

I thought I had read somewhere that normal background levels are usually under 100 CPM, and that if they go over that, this is cause for concern. Is that correct?

Any guidance anyone can offer on this would be much appreciated.

Thank you.

Mark, thank you very much for your temperature/pressure/rain radon artifact references re:
1. "The local weather (especially rain, temperature, and pressure) can have very large effects on the concentration of radon gas and its decay products. Basically, higher temperatures and lower pressures cause radon gas to seep more quickly out of the ground. This phenomenon is what causes most of the spikes in the RadNet plots. You can tell because a lot of the spikes occur on a daily basis and correlate with temperature variations over the course of one day. This diurnal variation in radon concentration is well-known..." (bandstra, 2011-06-06) http://www.nuc.berkeley.edu/node/4087#comment-9870
2. "...Assuming that there are no instrumental effects, the spikes in the EPA graphs would be caused by naturally-occurring radioactive isotopes, mostly from the decay chain of Radon-222." (bandstra, 2011-06-06)
http://www.nuc.berkeley.edu/node/4087#comment-9870
3. "[T]he reason the radon decay products vary so much is due to the local weather conditions. Radon gas seeps up out of the ground from the decay of naturally-occurring uranium in the soil (U-238 in particular). It is a heavy gas, and so it prefers to stay near the ground. The atmospheric pressure and temperature can greatly affect its concentration....
So there can be huge variations in radon concentration (and therefore the concentration of its daughters) over a single day, just due to temperature effects. This can explain the large spikes that many people are noticing, many of which happen over the course of a day or so." (bandstra,2011-06-06) http://www.nuc.berkeley.edu/node/4087#comment-9916

***

Yes, I can see how radon levels over the 'course of a day or so' can be effected by temperature change, pressure, or rain "over the course of a day or so". Yet, I am still puzzled by a number of factors that do not appear to be easily explained by the above points with regard to the sudden and persistent very high gross beta peak increases for the city of Los Angeles. EPA reported gross beta peaks for Los Angeles have been topping 100, 150, 200, and even 250 CPMs (plus in a few instances, approaching 300 CPMs) from July the 24th through August the 8th, 2011. Even continuing through today, 8/11/2011, beta CPMs are still going over 100 CPMs for Los Angeles. So, some points to ponder:

1. The gross beta 'hot' spell for Los Angeles' has not been just a 'one day or so' showing of sudden huge increased peaks for gross beta radiation levels. Rather, going on for 3 straight weeks, beta levels for Los Angeles uncharacteristically have been peaking very high. And, currently are continuing to do so, though now at somewhat lower levels.

2. Yes, I can entertain how temperature, pressure, and rain can effect sudden increases in radiation. If increased temperature/pressure is causing increased radon to surface, thereby causing sudden, skyrocketing beta spiking in Los Angeles over the past several weeks; then when BRAWM's radon decay test is applied to the above data, shouldn't the radon test results come out positive? That is, if radon is contaminating background radiation levels, extremely rapid decay should be present within a 4 hour period following initial reported levels. Yet, this is not what is happening re the EPA reported beta level peaks for Los Angeles. BRAWM's radon screening test came out negative. That is, overall, the gross beta levels for Los Angeles, since July the 24th have not been significantly decaying at 40 minutes by one half. And at 4 hours, beta radiation levels have not been returning to normal background levels to be expected for Los Angeles.

(**Above radon test reference is to Mark Bandstra's: "To prove that the radioactivities result from the decay of radon progeny and not radioisotopes from Japan, a simple experiment can be done. The count rate of the sample must be measured consistently over the course of time. In about 40 minutes, the excess count rate should be about half of what it was at the start of the test. In about 4 hours, the count rate should have returned to background levels. This half-life of approximately 40 minutes is a result of the decay chain of Pb-214 (27 minutes) to Bi-214 (20 minutes), both radon decay products and strong gamma and beta emitters. Nothing with a half-life this short has made it across the ocean from Japan, and nothing with a half-life this short could still exist in any appreciable quantity even a couple days after March 11.")

Again, if the increased gross beta levels for Los Angeles are due to contamination of radon and its daughters, shouldn't the beta levels in Los Angeles have been decaying significantly by the 40 minute time frame, and at the 4 hour period down to background level? But, no, gross beta levels have not significantly decayed at 40 minutes and at four hours following reported levels.

3. Yes, I agree that increased temperature/pressure can correlate to sudden increases in radiation. Over this summer, however, Los Angeles has experienced higher temperatures than those currently being experienced. Why then haven't these prior hotter periods of temperature in Los Angeles also resulted in sudden, high spikes in gross beta levels? Yet, beta radiation levels reported by the EPA prior to July 24th, 2011 have been essentially at background levels-- even during very, very hot spells for Los Angeles. All of the sudden, as of July 24th, the beta radiation levels for Los Angeles increased. At the end of the day, I am still left wondering. Why?