hey y'all! My old friend Tom (2/3 Marine) recently had an adventure in trying to find KK1991. take a look at the description on this mark. and dont miss Tom's log and photos.
Fun description, log and great pictures. Found one the other day near the Ridgway State Park and cannot find the BM site on Groundspeak. It was a Dept of Interior BM. Would that make a difference if it was listed on Groundspeak?
2/3 Marine is the authority on BMs, so i would advise you to shoot him an email with your questions. i know of at least one USGS BM we found that was not in the GC database. i think he reports them to the USGS somehow.
there are PIDs listed on GC.com that are not USGS BMs though. they can be logged just like any other BM. hope that answers your question.