According to Saito-sensei, the cutting slits around the OMC and OMMT tanks were made and their surfaces were covered with soft material to avoid spring water. After that, the painting was done. So the slit surface maybe not be visible. The cutting slit area is the mortar area that is a little bit higher than the surrounding area.

We are now discussing the present support rods for the pump unit should be released from the surface in the inside area of the slit cuttings. However, don't you think the present support is rather desirable, assuming no vibration from the Ion pump because all stuff of OMC-OMMT-TMP/Ion-Duct can be put inside the cutting slit area?  If we put TMP/IO unit on the outside area of the cutting slit, this structure can be the path of vibration from outside to OMC/OMMT.

In this sense, the removal of KF40 bellows is important, and actually it was removed.

Strictly speaking, the Ion pump body is now supported by one? rod that is put on the cutting-slit-outer area because it's weight is so heavy. This is the only one path to introduce the vibration from outside to inside, except for the GV side and some cablings. So is it better to change this rigid support with a labo-jack-like lifter with a rubber? If this support rod is also in the inside area, it is no problem.