Concrete, even though it is highly porous, can be useful in brine ponds. It needs always be used with a flexible liner like an RPE liner because it is porous enough that it acts like a sponge. An impenetrable barrier will need to be placed beneath it to prevent seepage.
However, using concrete in a brine pond can make it easier to collect salt by providing a solid surface for heavy equipment, which in turn protects the flexible liner from damage by the equipment. A layer of concrete on top of the flexible liner also helps prevent seepage through the liner, too.
