Question $1[12$ Marks$]$

$1\mathrm{.}1$ A construction site experienced a $3-$metre trench collapse during utility installation, causing worker injuries. Safety protocol gaps are suspected. Name four trench excavation safety regulations that could have prevented this incident.

$[4]$

$1\mathrm{.}2$ As an engineer tasked with designing a retaining wall to support a slope with a high$-$water table. Identify the critical factors that should be considered to ensure stability and safety.

$1\mathrm{.}3$ Explain why it is necessary to remove vegetation, topsoil, and other debris from a construction site before commencing earthworks.

$[2]$