Based on the track record of ineptitude coupled with the propensity of Tepco and the Japenese government to lie their their teeth , the spent 4 pool structure must be worsening. Expect denials right up until the moment if falls down....then the apologies will start...... ,

Title: Water Level Measurement for the Verification of Reactor Building Health
Source: Tepco
Date: April 13, 2012

Purpose

To verify the reactor building health, we checked the levelness of the spent fuel pool (SFP) and the reactor well before commencement of cover installation work for removing fuels of Unit 4.