The NEC requires kitchens to have two 'small appliance' circuits for countertop use, and that these receptacles be GFCI protected. These circuits may also serve other locations in the kitchen, pantry, etc.
The NEC is silent as to what's under the counter. Outlets there can be on these required circuits, but they don't have to be. Nor are they requires to be GFCI protected.
A common practice is to serve the dishwasher / disposal from the first receptacle on one of these circuits. In that instance, part of the duplex receptacle will be switch controlled (for the disposal). The circuit then continues to the second receptacle, above the counter, which is the GFCI that protects the rest of the circuit.
Something similar is done with the other required circuit, only the refrigerator is served first, "before" the GFCI.
I believe this meets the requirements of the code; good design is another matter altogether. I've become accustomed to massive kitchens, with more electrical gadgetry than the bridge of the Starship Enterprise. Besides the usual counter, there is an island, a bar, a breakfast nook, a walk-in pantry, a prep / wash area, a wine cooler, a refrigerator that is larger than a Yugo, a trash compactor, a toaster-oven (built in), a microwave big enough to dry your laundry, and enough lights to perform surgery.
Two circuits? Closer to two panels! But, I drift.
Unless you have a booster heater with that dishwasher, there's plenty of room for a disposal on that circuit.
Of course, there IS the Tim-Taylor disposal, with the Briggs & Stratton 2 cycle engine ...
