Possible sewage leak found

[Curtis Towers]

Hello. I am about to go under contract for a property. The seller notified me that when the foundation was replaced in November, a fresh water test was passed, but a possible sewage leak was spotted. The foundation wasn't insured because of this. They have had no issues with it. Should this scare me away from purchasing? What steps do I need to take to ensure I won't have a hefty repair on my hands?