> In some areas you will find:
>
> 1901 Set Stone, Ties: x, y, z etc.
> 1925 Set Hub over Stone, Ties: x, y, z etc.
> 1945 Set 1/2 IP, Ties: x, y, z etc.*
> 1979 Fd IP and set IP in new paving over existing, Ties: x, y, z etc.
> 1990 Set PK nail after resurfacing, Ties: x, y, z etc.*
> 2000 FD PK nail
> 2002 FD MAG nail*
> 2009 Set spike from ties, Ties: x, y, z etc.
>
> In 2013 some surveyor cites each * as a reason to dig a hole in pavement. In 1945 the surveyor didn't record how/why he set IP, and in 1990 the surveyor failed to document how he set the new nail, then in 2002 someone called it a MAG nail of all things.
>
>
> There is a time I don't dig. Hardsurface roads without good reason. I was once told "some people look for the top of the monument, some look for the bottom."
>
If the current monument does not have a traceable pedigree to the original, and/or if it doesn't have the stature of long-time acceptance & reliance, and if there is the slightest likelihood that the original or a documented pertetuation of the original monument's position still exists under the pavement, that is sufficient reason for conscientious surveyors to dig. But there's a few questions one should ask first.
Which set of ties was the spike set from? Has anyone attempted to locate the records of the surveyor from 1945 to see if he notes having found either the stone or the hub? Could be that he did but the note just didn't make it from the field book to the map.
What about contacting one of the more recent surveyors, such as the one who set the PK and the one who found the Mag nail? Did the guy who set the PK perform a diligent search for the previous monument(s) and ties? Did he use previous ties to determine the position? Or, did he split road widths or resort to proportionate measurement without having done more than a cursory search of the paved surface within a foot or two of where he expected to find an IP? Is it possible that the previous IP is simply under a couple of overlays?
Did the guy who found the Mag nail properly ID the nail? Was it really the PK? What did he do to verify that it was in the correct position? Or was he so careless as to call it good because it was within [whatever tolerance makes him comfortable] of where he expected to find something else?
It's possible that one could do a little extra investigation and find the info that ties the current monument back to the original, or at least back to the last accepted and significantly relied upon monument, but maybe not.
We aren't licensed and hired to simply measure from any old piece of scrap that looks like something someone may have set as a monument. We are expected to do a professional job, and that means thoroughly investigating to ensure that the evidence we rely upon to re-establish existing boundaries is the best & most reliable available.
Unless all the affected properties have been subdivided or resubdivided since 2002 and all relied on that Mag nail of unknown origin, that alone is enough reason to
look for the original. You might argue that crews commonly refer to Mag nails as PKs since they look so much alike, but Mag nails weren't around in 1990 when the PK was set, so there is nothing tying it back to the original corner location.
If you don't recognize that as more than sufficient reason to dig & verify, then perhaps you should rethink the standards that you work by.