Microfine cement grout injection (grout injection) can be a cost-effective method of soil retention, aiding temporary excavations. This is provided the grout works and excavation are designed and completed in an appropriate manner and under suitable conditions.

The linked publication and below infographic provides information for those considering the use of grout injection to support a temporary excavation.

This includes persons conducting a business or undertaking (PCBUs) and workers involved with designing, approving, procuring and installing permeation grout injection.

It is also for those neighbouring proposed excavation works who are requested to sign a BA20 or BA20A for potentially affected land. It is particularly relevant to those installing in-ground pools.

Figure: Basic steps in the grout injection process/ involvement of various industry participants (PCBU's)