What's more significant than the number is Fukushima Minyu's interpretation that the contamination may be from the water in the trench(es) that contain extremely highly contaminated water from April/May 2011.
From Fukushima Minyu (1/11/2014):
2.2 million becquerels [per liter] detected from a well near the harbor at Fukushima I Nuclear Power Plant, upward trend continues
A large amount of radioactive materials have been detected from observation wells on the ocean side of Fukushima I Nuclear Power Plant. On January 10, TEPCO announced that the density of all-beta including strontium-90 had further increased and the latest measurement was 2.2 million becquerels per liter, the highest recorded so far.
The well is located on the east side of Reactor 2, about 40 meters from the plant harbor. The water sample was collected on January 9. The density was even higher than the sample taken on December 30, 2013 which had 2.1 million becquerels/liter.
The well is located near the underground trench for electrical cables where water with extremely high contamination was found leaking right after the March 2011 accident. It is likely that the contamination is spreading into the surrounding soil.
Jiji Tsushin reports the same news but it says "The cause of the high all-beta measurement is unknown."
The level of radioactive cesium in this water was ND (not detected).
How "extremely high" was the contamination of the water that was found leaking from the Reactor 2 turbine building via the trench into the harbor in April 2011?
From TEPCO's press release, 4/5/2011:
Iodine-131: 5.2 billion Bq/Liter (or 5.2 million Bq/cm3)
Cesium-134: 1.9 billion Bq/Liter (or 1.9 million Bq/cm3)
Cesium-137: 1.9 billion Bq/Liter (or 1.9 million Bq/cm3)
The air dose rate measured above the water in April 2011 was over 1 Sievert/Hour (survey meter went overscale).
If this trench water is spreading in the soil, it makes sense that cesium is not detected from the water, as cesium has been bound to the soil.