As can be seen on the latest photo's there is a roof being build above the loading platform. The rest of the opening will be taken up and closed of by the Hogwarts express. Combined with engine sounds, station sounds, quartermaster calls, maybe ambient music and the leaving and entering of the guests themselves I don't thing a few screams from a coaster train riding behind these walls every few minutes will disturb the experience.
The "tranquil" village of Hogsmead also doesn't suffer from the duelling coaster on the other side of the wall and a kiddy coaster at the end of the street.