A Mercury Contaminated Building

I was reading the paper a few minutes ago and came across an article that mentioned a mercury contamination. The building was used as temperature controlled facility, but many leaks and spills happened and the building closed down. Those leaks seeped into the walls and remained there. The building was reopened as a Child Care center when the man who owned the building sold it to the Kiddie College franchise. Low and behold the man who sold the building did not mention the building was contaminated. Once the truth was revealed later on, over 100 kids were reported to be infected. No severe harm has been done or seems to be expected. I believe that any kind of contamination needs to be dealt with in any way possible. The longer the contamination is left unchecked, the more harm it can do to civilians living in the nearby area.