This is what the pit would look like

Jointing pits, also called splice boxes, are intended for enclosing a spliced cable connection. These pits contain waterproof cable joints and are generally placed along straight sections of a cable route. These cable pits must be correctly sized to accommodate the size of the connector and cables running through it.

Essential Energy is using a joint pit to enclose cabling ....

Here you can find the design document for the Join pits.