There are a number of alloys that are used when working with desalinization plants, but the effective ones are cost prohibitive.
Even if they had a way of pumping it out cheaper, it still comes with issues that are costly. There are chemicals used during the process which pollute the brine and cost money to remove. It also comes out much warmer than surrounding water which disrupts the ecosystem. The brine eats up oxygen levels and suffocates animal life in the area.
They are trying to dilute the brine before releasing it back to the ocean but this is either not effective enough since you're using salt water from the same source you're pumping into, especially if the area doesn't have strong currents to carry it away. Or you're using water which doesn't have high salt levels and can dilute it to healthy levels, which you might as well just treat and use in the first place instead of using saltwater.
It's not an easy problem to solve at the moment
deleted by creator