Mercy Lives: 24-Year-Old Horse Pulled Out of Septic Tank in 2 1/2-Hour Rescue in MondexSeptember 20, 2016 | FlaglerLive | 21 CommentsA dozen agencies and veterinarians were mobilized to rescue Mercy, a 24-year-old horse that fell in a septic tank Tuesday morning, managing the rescue after two and a half hours of efforts.