Mass Effect 3 is a 32 bit application. And as with any 32 bit program, it is limited in its memory. If memory usage ever reaches around 3.5 gbs it will crash the game. In an unmodded playthrough, this limit would never be reached. However, if you combine big content mods like PV with big textures mods like ALOT taht limit is easily reached.

Can anything be done about this?

The answer is no. The only thing that can be done is to cut off some memory intensive features in PV. That is what the PV ALOT patch is for. It disables loading multiple levels on the Citadel to prevent a memory overload. This patch must be used if you intend to use PV and ALOT together. The other thing that I reccomend is to set all lods 2048 rather than 4096 in GamerSettings.ini. I also reccomend you do not install the static lighting upgrade. Apart from these measures, there is not much else that can be done.