



 
Hi Steve, My diagram is not to scale and I also changed one of the dimensions. If the pool has a diameter of 24 feet and the trench is 2 feet wide then the outside diameter is 28 feet. I would first convert the diameters to inches. Use our volume calculator to find the volume of a cylinder with diameter 28 feet (converted to inches) and depth 26 inches. Use the volume calculator again to find the volume of a cylinder with diameter 24 feet (converted to inches) and depth 26 inches.The difference is the volume of sand you need. Penny  


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