Some High Quality Advice from those in the know..! Just to throw in my two cents,let's recap some of the high notes:
1.) Know your average water table and soil type. The drought has definitely brought water tables down.
2.)If you haven't cut a trench all the way into the foundation yet,try to have your lines rise as you meet the foundation to enter. This can avoid the "French Drain" idea of bringing groundwater flow directly toward your foundation.
3.) I'd use 1" line in a foam filled water resistant casing,like the type Central Boiler sells. Expensive,you bet. But I like your idea of attempting to do this right the first time for the long haul. Getting that stuff to push through a larger PVC Conduit can be a chore,but may provide dividends and protection in the long run.
4.) Indirect hot water heating would seem to allow you the best use of a much simpler 2 line supply and return circuit with only one foundation breach.
5.) Lastly,an old foundation man fortunately taught me that any time you breach anything below grade through the foundation wall,you should always angle it up so that your inside piping comes through the wall higher than it is outside the wall. This gives much better resistance against ground water pushing in to the basement or crawl space. Seeling the hole is much easier,also...
Just a condensing of the great thoughts above,and I'm sure more will follow. What's so good about this Board is the fact that if someone had a question about how to build a heart/lung machine in a pinch,we've got enough well-rounded Coalers here that would come up with a solid game plan for it. Good Luck,and please follow up here with your results. Send us a few Snaps of the action in progress if you can. Like Freddy has said in the past "We Love Pictures"