I am in the process of draining the pool to replace the liner and repair a rust spot. I also noticed this damage. The pool was "professionally" installed in 2008. We did have trouble with the installation in that the pool fence that we had also installed was poorly done and we had to remove it , leaving holes where it was attached to the uprights open. I am not sure how well the rest of the job was done but I did pay a couple grand for the install, not that it guarantees the work but it was my intention to have it done correctly and solidly . I would like to use it for a few more years.
I am adding photos (trying) in hopes that someone can offer advice.
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