Out of context it is difficult to tell. The owner of something should be contacted at least 2 days before you leave. Perhaps the owner is the owner of the hotel at which you are staying. Perhaps the owner is the man who owns the land which you will be crossing when you take a hiking trip. Perhaps the owner is the owner of a boat you will use for a fishing trip. Whatever the case, you can probably ignore the last part "where you are required to do so." That's basically saying contact the owner unless otherwise informed you do not need to.