I just bought a 21'x52" above ground pool. I am going to use a saltwater system with it. Do I need to ground this pool ?
A basic installation, would look something like this.
You'll bury a continuous loop of 8 AWG solid copper conductor around the pool 680.26(B)(2)(b)(1 & 2). The loop should be 4-6" deep 680.26(B)(2)(b)(5), and between 18-24" from the pool 680.26(B)(2)(b)(4). You'll then bond the frame of the pool to this loop, at 4 uniformly spaced points 680.26(B)(2). Next you'll bond the pool water to the loop, using a special bracket on the filter basket 680.26(C). Finally, the loop is bonded to the filter motor 680.26(B)(6).
Additional items to be bonded
The information provided here applies to the specific pool mentioned in the question. Installations for other types of pools may vary.
Make sure to have this, and all other projects properly permitted and inspected.
All code references from National Electrical Code 2011
You need to BOND the pool structure and any equipment (motors, etc) or metal parts associated with the water circulation system. You also need to bond the water itself. Ground rods are NOT required other than for a sub-panel (if installed outside the house).
Pools are quite complicated as far as the electrical requirements go. IMO this is NOT a DIY job and should really be done by a professional electrician experienced in this kind of work.