I believe I had read just dilute it until concentration is ok then release.
But might be more tricky than that ^^ : https://www.sciencedirect.com/science/article/abs/pii/S00489...
Have a pump that draws in 10L of ocean water for every 1L of brine you need to dispose of, mix 'em up, and discharge the 11L of only-slightly-saltier water back into the sea.
Not sure when it makes more sense to do that vs. having a leach-field type of brine discharge. They both ultimately do the same thing, but one requires more mechanicals, the other requires more piping and "passive" infrastructure.