We are going to partially boil some potatoes and then slice them into wedges to bake them... Since they will be in hot water it still necessary to individually the wash and scrub each potato?

All potatoes are flumed in water as they go down the sorting lines and washed before being packed into cartons or bags, it doesn't hurt to rinse them one more time to get any surface dirt or sand off the potatoes you receive. Boiling in hot water is just going to push around any dirt particles or sand. As far as scrubbing, just check a couple of the potatoes as a sample and if the eyes are deep they can easily trap excess dirt. If shallow you probably can get away from doing this step.