Surveyed elevations are shown in Figure for a 50' x 50' grid at a proposed parking lot location. The amount of borrow needed to bring the area to an elevation of 90-ft is most nearly:
Solution:
Find the average elevation:
Average = 87.6-ft + 87.6-ft + 87.6-ft + 88.6-ft / 4
Average = 87.85-ft
Change = 90-ft - 87.85-ft
in elevation = 2.15-ft
Fill Required = 2.15-ft x 50-ft x 50-ft
= 199-yd^{3}