Q237
A backfill mixture commonly includes:
A.
Coal and water
B.
Cement, tailings, water
AnswerC.
Lime and clay
D.
Silica and gravel
Answer: Option B
Solution
Answer: Option B
Solution:
Backfill restores voids with a stable mixture.The correct answer is: Cement, tailings, waterSupports ground, reduces surface subsidence, and helps waste disposal.Can be placed hydraulically or mechanically.