Help! I have read posts on how to level the ground for installing above ground pools. I wanted to use the 2X6 10ft board attached in the center of the pool area. My husband hammered stakes around the area and stretched a string with a small level on it around from 1 stake to each of the others. he hammered the stakes to make them level with the 1st one. After he had them all "level" he stretched string back around them and measured with a yard stick the distance between the ground and the string at different places across to be sure they were within 1" difference. Is this procedure ok to use? I question if there are still some uneven spots in the area. Any feedback/advice would be appreciated. We have the sand coming tomorrow so want to be sure it's right before we go ahead with putting it down.