Re Har HaMenuchot.
The terraces that are built on amudim – how is this considered burial in the ground of Eretz Yisroel.
The reason why it can be considered burial in the ground is because a layer of earth is laid on each “floor” of the cement terracing, ensuring that the burial is “in the ground.” This layer of earth is connected with the earth on the ground by a continuous “earth connection” on both sides of each cement floor.
When it was built, the construction was accompanied by constant consultation with leading rabbis. This does not mean that all poskim approve of it, but is generally accepted (though for an important rabbi, Rav Elyashiv ruled that it was not fitting, and the body was transferred to a different plot).
Many prominent rabbis have given their approval to this method of burial, but others have expressed their objections to it. Among the former are Rav Elyashiv, Rav Schechter, Rav Wosner, Rav Ovadyah Yosef, Rav Amar, and in the past Rav Kolitz and Rav Mordechai Eliyahu. However, Rav Wosner has recently retracted his original agreement to the matter (explaining that he was not hitherto aware of the precise description of the method), and a number of authorities have disapproved of the method, including Iggros Moshe (see Yoreh De’ah 3:144), the Minchas Yitzchak, and members of the Eidah Chareidis.