Ann: Quarterly Activities and Cashflow Report, page-33

Physical test work - lab/pilot plant set up they can't do remotely.
However there is a LOT than can be done remotely(from home) in terms of project development/planning.

Just hypothesizing here & maybe some clarity from TNG would be useful, but awaiting the test work results at this point in time could be necessary for process flow diagrams/calculations - ie what flows, pressures, temperatures, acid concentrations, dwell times etc OPTIMIZE the plant.
What I'm getting at is that by now they should know the motors, dryers/ovens, heaters, pumps & pipe sizes, dosing pump rates IOW all the equipment sizes & with this they can complete the detailed engineering for MCCs, air & water systems, cables, lines, valves.
Not as simple as this, but the test work they are waiting on should be to just plug the numbers into the control system to tell the equipment they already should know they require, what to do.

That is where we should be. Wonder if that's a question TNG would answer.