I see the directions: "Fill the hole 1./3 full of water... and more water." Wouldn't the upper layers not have enough water to set without mixing?

Dana, After pouring approximately 1/3 of hole with water and adding the Fast Setting Concrete Mix. The water does not saturate the dry powder on the top. Add more water so it is activated. Should the water pool or puddle. Dab the surface dry with a sponge or old rag.