From the next section I'm reading, it appears that basically none of the gauges installed inside the reactor pressure vessel are to be trusted, making estimates about the conditions inside guesswork. Take this last one for example:

In the present state, it is thought that steam continues to escape from the gas phase part of the RPV, but the RPV pressure is higher than the D/W pressure, so it is assumed that the opening is not large. However, the pressure changes after March 23 are changing in parallel with the changes in PCV pressure, so the possibility cannot be denied that there is a problem with the measurements.

_{*Lunatic*, n.
One whose delusions are out of fashion.}