CASUC =
Constantly
Applied
Single
Use
Coolant
Doesn't necessarily require mods, you can move items in and out manually should you wish. 
True CASUC uses components that are /destroyed/ by the reactor. This would be akin to constantly replacing cooling cells and just tossing the heated ones in to a lava pit; or even just running them until they burst (fed by hull plating) and slapping in new ones as they pop.
What we see now are what I call CARUC (Reusable/Recyclable/etc); in this form the only component that is lost is from an infinite spring of water; buckets containing water and/or ice it's self are sent in to evaporate. The bucket form is done using other mods, and often without any external power; so thusly it is provided without any cost in eUs.
True CASUC uses components that are /destroyed/ by the reactor. This would be akin to constantly replacing cooling cells and just tossing the heated ones in to a lava pit; or even just running them until they burst (fed by hull plating) and slapping in new ones as they pop.
What we see now are what I call CARUC (Reusable/Recyclable/etc); in this form the only component that is lost is from an infinite spring of water; buckets containing water and/or ice it's self are sent in to evaporate. The bucket form is done using other mods, and often without any external power; so thusly it is provided without any cost in eUs.
While i agree that CARUC is appropriate to use, a water bucket is a single use coolant. You can't use the same bucket twice without filling it with water between the runs.
In my ideology, filling buckets need to cost something (In my case that is energy) and pumping water to fill the bucket also needs to cost energy. To move the buckets around the reactor also needs to cost energy.
Thus, IMHO, CASUC and CARUC are both appropriate for the reactors i would use. To me, a CARUC is a reactor that is fed buckets that are refilled without any additional cost. (For example, using RP2 deployers and RP2 retrievers etc. Even though RP2 needs bluetricity to operate it's retrievers i don't see it as it costing that much, you make a few solar panels and they will give you the power you need for ever.
I will not use solar panels until they are balanced in a way that using them means spending as much time making and placing them as it does building the entire reactor.
But Eloraam has noted that she might make a IC2->RP2 energy conversion machine. So if i can power my retrievers with my reactor (making it a self sustained closed loop) then i would use retrievers and i would call it a CASUC once more. (Energy is converted into coolant work)
While I agree with your logical distinctions, I feel that you're conflating them incorrectly with the terms CASUC and CARUC. Said terms do not in any way reference the cost of cooling operations in energy, but are instead focused on the loss of material for cooling (non-renewable (CASUC) versus renewable (CARUC) versus no loss at all (unlabeled/normal)).
I am not sure what terminology makes sense; just as you /can/ build an RP2 reactor out of 'free' level reusable cooling, so too can redstone engines be used (or so I've read on the forums) for a BC based solution.
Reactor Powered - CASUC/CARUC seems like what you want to call things; RP-CASUC for synthesizing all consumed resources out of UUM/grow ops powered by the reactor, and RP-CARUC for the same but using self-renewing resources (that is, ice or water-buckets).
Ice is also a single-use coolant. You can use each ice block once, and only once. Thus an ice reactor is a CASUC, because it's continuously applying single-use coolants, even though the coolant is renewable.
That is true; however using ice does not lessen the world; where as using disposable materials does.
