This is rated with a terrain of "4" due to the fact that you'll need a boat to get to the cache site. Rentals are available, but to be honest the rental pier looked pretty deserted to us. We placed this cache using our inflatable kayaks -had a lot of fun doing it too!
You barely need a GPS to locate this cache - I should tell you that if you're like most people with an accuracy reading of +/- 20'... you're in for a surprise. The small island that this cache is located on is actually smaller than the error range!
The boating is not difficult at all. The island appears to be frequented by some of the folks (kids?) that live along the lakeshore - there is a fire pit on the island.
I'm putting a fairly descriptive hint below, just because the island would be a serious pain to search (lots of growth) and there's no need to make it a tedious cache. If you've gotten a boat to do this, you deserve a break!
Note that the cache is a very small Rubbermaid container and is at ground level (some of the cache is below ground level, actually, but its not too near the water). The cache is not in plain sight.
One last thought - for you boaters, there's a great lake at Kittatinny Park which is fairly close by. (No boat rentals there, though).