Everything in your post is wrong. You need to stop applying the...

Everything in your post is wrong. You need to stop applying the same logic and understanding that you use for hard rock mining projects.

(1) If they are producing all year round then they will need to produce in the wet season. If they were only producing during the dry then you might be correct. Assessing the impact of rain water ingress (=dilution) is correct. To ignore the impact of the wet season would be silly.

(2) Depth of the trench has nothing to do with the amount of brine you can recover. That is governed by grade and recharge rate, the latter being the bit you are not appreciating.

(3) Cut off is not a useful concept in a brine project. Average grade across the trenches is what’s important. If one is concentrated and the other dilute then you’ll get the mix (unless you shut down the dilute trench).

Try and think about it not like a hard rock project.