We have a slope, too. We built a retaining wall around the pool, leaving enough space to walk around the perimeter of the pool. We buried a piece of flexible corregated perforated pipe in this space and directed the water away from the pool. I don't know what you call it, but there is some kind of a cloth sleeve that the pipe was put inside. It lets water in but keeps dirt out. Then, we covered the pipe with rocks. It seems to have worked as we have never had an issue with water.
There are some pics in the following thread that were taken when we replaced the pool a couple of years ago. You can't see the drainage pipe, but you can see the retaining wall.
http://pool9.net/wm-pool-advent/
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