ALTERNATIVE VIEWPOINT

But what we can do is extrapolate based on what we know now.

We know that emissions have subsided, this can not be in dispute because we don't see rising levels of nuclides in air samples. We know that based on historical data, Chernobyl gave California 7x more fallout than is currently occurred
from Fukushima. So if it takes 3 months for Tepco to cease all emissions (per their plan, and some experts
believe it will happen at 2 months), then we would be at under 50% of what California received from Chernobyl.

Even if emissions go longer, emissions would have to be 5x current levels to even be half of Chernobyl output, based on CTBTO readings to date.

There just isn't any credible evidence that makes this event larger than what we have already lived through.

The intent of my previous post (my first in this thread, FWIW) was simply to encourage clarification. I assure you it wasn't an attempt to pin you down into a simple "I agree" or "I disagree"!

What does "we're seeing lower levels" or "levels are dropping" mean and what doesn't it mean? I think some elaboration is required to understand this because there are various levels/amounts (for each and every radionuclide) including:

1) That which is in the air and has not yet been deposited
2) That which is being deposited... the additional wet & dry depositions
3) The cumulative total amount deposited (since the beginning)
4) The cumulative total amount deposited minus that which has decayed (what is still present in the environment somewhere)
5) The cumulative total amount deposited in a specific location minus that which has decayed and minus that which has migrated elsewhere (what is still present in the environment but not at that specific test location)

For example, surface air concentrations and rainwater concentrations might decline and also result in new depositions declining. Until all new depositions cease, total cumulative deposition would continue to increase. Short-lived radionuclides may decay faster than the new depositions of said resulting in a declining level of what is still present in the environment. Long-lived radionuclides may not decay fast enough to offset the new depositions of said resulting in an increasing level of what is still present in the environment. Winds, runoff, deeper soil penetration, and/or uptake into harvested crops can lead to a specific surface soil location containing lower concentrations of a long-lived radionuclide but that doesn't mean the amount present in the environment has declined to any significant extent or at all. For example, I would think it critical that farmland soil testing always be accompanied by crop testing because soil concentrations would tend to fall as a radionuclide is taking up by the harvested crops.

Although my description may be imperfect, I think it is a fair quick glance at the complexities of fallout and the environment. When I earlier asked you if you agree, I was actually trying to ask if you agree that there are such complexities as well as encourage you to shed light and clarification on them.

I bothered to do this because I think over-simplification is one threat we face. A specific real world example would be Japan and hotspots such as Iitate Village. I can remember Japanese authorities publicly declaring that "radioactivity levels were falling" (which to some extent was likely true, as they *later* admitted that they were only performing simple total background type analysis) even as new depositions of longer lived radionuclides continued and rendered the land less and less fit for habitation and especially for farming which was common in some of the hotspots).

Many years ago a neighbor of mine had some kind of trash day accident with a bean bag chair. When I took my trash out it at first looked as if it had snowed... the surround yards, sidewalks, and street were covered in tiny white pellets. Even after a concerted cleanup effort (which included vacuuming some pellets out of the grass!) there were a massive number of pellets remaining. Although they clearly weren't decomposing, over time they slowly disappeared from sight. Some were blown and washed into the storm sewer and subsequently into a local river and so forth and so on. Some were blown and washed into those places on our properties where things naturally collect. Some simply worked their way down into our yards and gardens where they could be dug up long after their release. The Fukushima "white pellets" are a mixture of fast, moderate, and slow degrading ones. I think in addition to cheering the ones that are "biodegrading" quickly as well as those that get blown and washed away from our specific yards, one shouldn't forget about those that will be around for a long time and an effort should be made to track their migration.