According to your posts, even the home inspector could not find the septic, and the appraiser took photos of well water.
Now you want to say the septic was exposed when the appraiser performed the on site look-see? Where is that "evidence", that the appraiser didn't get there before the septic guy?
Three is no evidence of "concealment" and you did not do your due diligence to have the septic pass an inspection before you closed the sale. And oh, my, was that inspection a requirement of your agreement of sale, that you just let slide by?
So it appears that you concealed the septic and any issues it might have, by not getting the required septic inspection. A cleaning, is not, an inspection.
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