Originally Posted by
118.70
says that the IPA designs will join the approach path less than 8 nm from touchdown
Indeed.
The concern among community groups, as I understand it, is that in order to keep traffic landing on the departure runway clear of ATC-vectored traffic heading for the arrival runway for as long as possible, the former will follow fixed RNAV routings that will overfly areas that don't currently get arriving traffic overhead.
In addition, because they are RNAV routes, they will be flown more consistently (to RNP 0.15) so that the effect will be to concentrate traffic over the same path on the ground (similar to the effect noted in recent RNAV departure trials) rather than in the wider, less concentrated swathe that ATC-vectored inbounds (or outbounds on a SID/NPR) fly.