OReviewer: Screwing, nailing or otherwise permanently attaching your cache to something that is not yours is considered defacement.
Defacement Guidelines
Geocache placements do not damage, deface or destroy public or private property.
Caches are placed so that the surrounding environment, whether natural or human-made, is safe from intentional or unintentional harm. Property must not be damaged or altered to provide a hiding place, clue, or means of logging a find.
Please return the area to it's previous state as best you can.
OReviewer
Volunteer Cache Reviewer