The total number of samples for beta nuclide analyses from March 2011 to January 2014 is 20,866. It turns out that if the sample contains more than 200,000 Bq/Liter of beta nuclides, the instrument cannot accurately measure the radioactivity.
From Fukushima Minyu (2/15/2014):
167体で誤測定の可能性 ベータ線を出す放射性物質
Possibility of mistakes in measuring beta nuclides in 167 samples
東京電力が福島第1原発の汚染水測定でストロンチウム90などベータ線を出す放射性物質の濃度を過小に推計していた問題で、東電は14日、事故直後の2011(平成23)年3月から今年1月末までに測定した試料167体について、正確な測定できず、測定値を過小に推計した可能性があるとする調査結果を発表した。いずれも実際の値はさらに上昇する見通し。
TEPCO underestimated the densities of beta nuclides including strontium-90 in the analyses of contaminated water at Fukushima I Nuclear Power Plant. On February 14, TEPCO announced the result of the investigation that says TEPCO underestimated [the densities of beta nuclides] in 167 samples taken and analyzed between March 2011 and the end of January 2014. The actual densities are expected to be much higher.
東電によると、167体は、海水や観測用井戸から採取した地下水や、敷地内の土壌など。
According to TEPCO, these 167 samples were taken from the seawater, groundwater from the observation wells, and soil inside the plant compound.
東電が原発事故直後から今年1月末までに測定したベータ線を出す放射性物質の件数は計2万866体。これまでの調査で、測定機器では1リットル当たり20万ベクレルを超える試料は正確な値が測定されないことが判明しており、検体数を確認したところ167体に上った。東電は今後、これらの検体を測定し直し、正確な測定値を公表するとしている。
The total number of samples for beta nuclide analyses from immediately after the start of the nuclear accident and the end of January this year is 20,866. The investigation so far has revealed that the instrument [used by TEPCO] cannot accurately measure the samples with beta nuclides exceeding 200,000 Bq/Liter, and there are 167 such samples. TEPCO says the company will analyze these samples again, and publish the accurate results.
Only now TEPCO is allowed to admit to the mistake. Now that the 2020 Olympics will be held in Tokyo, and now that the Tokyo gubernatorial election is safely over, with the win by a pro-nuclear candidate with whom TEPCO is very comfortable working.
TEPCO correctly measured the sample with 5 million Bq/L of strontium-90, but they did not disclose the number because their measurement of all-beta including strontium-90 in the same sample was 0.9 million Bq/L, which was an impossibility. They sat on it, and sat on it until February 7, 2014.
According to tweets by nuclear experts, TEPCO has the analysis lab at Fukushima I Nuclear Power Plant with 30 staff members. According to these experts, it is barely adequate for the amount of work they have to do.
And where is the promise of "the national government at the forefront" by the Abe administration?
Now that the 2020 Olympics is in the bag and the governor of Tokyo is the highly blackmailable Masuzoe, Abe has moved on to his pet project - Constitutional amendment, which will be determined solely by him as the "CEO" of the nation.