As discussed in Chapter 5, acid mine drainage (AMD) poses serious dangers on the environment and human health. Doubtlessly, prevention of AMD generation is an important task in order to protect the environmental and health risks associated with it (Kefeni et al., 2017). Therefore, over the years considerable focus has been directed towards the development of technologies for the prevention of AMD. Currently, there are a number of approaches to preventing and/or minimizing the generation of AMD. Actually, prevention of acid production is preferred over treatment of AMD (Brown, 1996). Park et al. (2019) also argue that since prevention techniques do not require continuous maintenance, they are more sustainable than traditional remediation or treatment techniques. Moreover, AMD treatment costs can negatively influence the economic performance or even compromise the viability of a project; thus, AMD formation should be prevented (Pozo-Antonio et al., 2014). Therefore, only the most serious and unforeseen cases of AMD pollution should employ treatment techniques (Pozo-Antonio et al., 2014).
Taking into account that the oxidation of sulphide-bearing minerals and the subsequent AMD generation occurs in the presence of water and oxygen, and is highly accelerated by microorganisms, the general approach for AMD prevention techniques has been to eliminate or reduce one or more of these essential factors (Kuyucak, 2002; Pozo-Antonio et al., 2014; Park et al., 2019). This chapter focuses on a number of such techniques. In particular, the chapter discusses the following techniques that have been explored to prevent or minimise the generation of AMD: (1) control of water movement, (2) selective separation and blending of sulphide-rich materials, (3) physical separation barriers for water and oxygen, (4) inhibition of iron and sulphur-oxidizing microorganisms and (5) other methods, namely, sulphide passivation or microencapsulation, desulphurisation and electrochemical protection systems.