noun
backfilling; refilling
Technical term used in civil engineering, construction, and archaeology for refilling an excavated hole or trench with material.
配管工事の後、埋め戻しを行った。
After the plumbing work, they carried out backfilling.
遺跡の発掘調査が終わり、埋め戻しが始まった。
The excavation of the ruins finished, and the backfilling began.
埋める is the general verb 'to bury' or 'to fill in', while 埋め戻し is the noun for the specific process of refilling an excavation.
Compound of 埋め (ume, continuative form of 埋める 'to bury') + 戻し (modoshi, continuative form of 戻す 'to return'), literally 'bury-return', referring to putting excavated earth back.