Can a NUC fellow check my numbers?

I just want to see if I have the correct math from what I could piece together here and elsewhere online.

Thanks!

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In the Bay Area, fallout equates to 550 Bq/m2. That 550 is made up of around 500 Bq of I-131 and the remaining 50 Bq as Cesium, Tellurium, Barium and a few other traces.

Germany, in the south at the end of the Chernobyl accident, recorded surface measurements in the 5-50,000 Bq/m2 range for Cesium.

Right now, the total concentrations we are seeing here equate to 1% of those readings. The difference is that the concentration of radiation is mostly due to I-131 which will decay over the course of time (months). What remains, however will effectively not decay significantly in our lifetimes. That puts the Bay Area level at around 0.1% of the German levels. We can expect to accumulate 0.1 Bq/day of Cesium in dry weather and 0.25 Bq/day if it rains. Should levels remain constant, and the period of emission last 6 months (a reasonable assumption), that our total accumulation of Cesium would be around 450-500 Bq/m2 or roughly 2% of southern Germany.

The effects of the total level of Cesium would probably have some barely measurable effects on cancer rates (which currently stand at 1:250 in California, from natural sources). The effective dose of Cesium in the environment at that level would depend on how much one consumed from meat and produce, and at what levels. But a good rule of thumb would be around an additional 1 uSv/year (avg background is on the order of 0.1 uSv per hour).