TEPCO has forecast that water levels in the flooded unit 2 and unit 3 turbine halls are estimated to fall by about half a metre in about a month, to OP 3.0, assuming no change in water injection and rainfall. The system recently added a second train of caesium adsorption systems to increase throughput. The first desalination system is also up and running.
Seismic analysis of the seismic forces acting on units 2, and units 5&6, have found no structural damage as a result of the earthquake. TEPCO said it assumes that there is no internal damage inside unit 2, although high radiation levels prohibit people from entering the building. A time transient response analysis using design basis earthquake ground motion (Ss) was used. Shear strain in unit 2 anti-earthquake walls was estimated at a maximum of 0.17x10^-3 (in east-west direction, on the fifth floor), only 1/24th of standard maximum value of 4x10^-3. A further study of the possible effect of the high temperatures in the primary containment vessel, and activity in the suppression chamber in the basement on the analysis showed that they did not change the figures significantly. In units 5&6, earthquake shear strain forces using the same analysis were found to be greater (0.19x10^-3 and 0.33x10^-3), but still not sufficient to challenge the building's integrity.
Finally, TEPCO has restarted pumping the unit 6 turbine building. An earlier news article mistakenly reported that pumping out the turbine building had finished.
