I fish a similar rock quarry from shore quite a bit, whenever I have a few hours to kill and I don't want to drag the boat. They produce some nice crappie, yellow perch, bluegill and even largemouth bass. Most times I find the crappie to be suspended about 5' below the surface. Although sometimes they will be deeper. More rarely do I find them really shallow, except during the spawn.
I use two types of presentations. One is the slip bobber early in the season, with a 1/32 oz. marabou jig suspended beneath it. I vary the depth and use a very slow retrieve back to the bank. After a few fan casting retrieves, I change the depth of the jig and continue casting & retrieving along various points and humps that I know I can reach from shore.
The next presentation, which is very productive in the warmer season, is casting a 1/16 oz. jig head dressed with a BGBS (straight tail plastic) on the back. This I will cast out and retrieve slowly. I start out right at the surface, fan casting from where I'm standing and progressively count down until I locate active fish. Sometimes a slow rolling retrieve just off the bottom gets me bit, especially with the yellow perch. Hope this is of some help.
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