Discovered a severe vertical crack in a wall section of my polymer walled in-ground pool. One side of the crack is caved in by perhaps 1 inch creating a sharp edge. The crack is irregular and not near a wall seam. There are 8"x12" caved-in indentions all the way down this particular wall. The indentions start at about 1/16 inch in depth and get deeper going toward the end of the wall and ends at the indention with the large crack. I have done quite a bit of research and found little information on such a problem. Digging the wall up is not an option so I'm planning on repairing indentions and cracks by applying some type fiberglass/resin/bondo material. Does anyone any experience with making such a repair?