$($a$)$ Why is acid mine drainage $($AMD$)$ a problem?

$($b$)$ What are the differences in waste produced for every $1000$

$kg$ of rock mined in open pit and underground mining

operations? Explain why these differences exist.

$($c$)$ Describe three ways in which mine tailings are disposed of$.$

$($d$)$ What is Gs$?$

$($e$)$ What are the embankment walls of a tailings dam?

$($f$)$ What are the advantages and disadvantages of dry

stacking?