The black one above it is a full pond before evaporation.
The one on the left has some water in it that has evaporated leaving some salts.
I presume they will scrape the salts away and refill.
Ggp are waiting to see how fast the evaporation rates before construction of a larger pond.
Also checking the flow rates coming out to the ponds to see how quick these ponds will be filled.
They need this information before planning the Decline recommencement
