This type of project will need a crew of 4. Someone to run the average double drum grout pump, two skilled labourers to supply the pump with grout in 40 Lb bags and one person at the grout head. Yuo can use both drums for mixing grout but usually we run with one full of grout and one with water to clear lines quickly if blockages occur.
Production should be about 2- 3 pallets per day I think about 56 bags per pallet of cement and 70 bags /pallet if you are using bentonite.
This rate can be increased by using more automated or larger mixer equipment but for your purpose this should be sufficient.
Intrusion Prepakt /marineconcrete.com