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Handling Of Erroneous Recovery Reports ?


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Discovered recent bad recovery reports in NGS data base.


Report to NGS? If so, how? Maybe an e-note to Ms Brown or Ms Malone suggesting attempt to confirm with the report originator?


New recovery report with correct info and ignoring previous erroneous report?


Let it go?


Other? What?


Example 1: Latest report for Tri Station GV5626 describes location, not of 5626 but of Reference Mark DC5723 MIDLOTHIAN RM 2 (no data sheet).


Example 2: Latest report for GV2111 describes location of GV5626 (12 feet away from 2111). There are other errors in these reports.


Don't want to throw rocks at this sincere attempt to help - and I guess the error would be obvious to a pro - but seems a shame to leave the incorrect, uncorrected.


What to do? What to do?

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I think I agree-- just file your best report, being sure to state the facts that will let the next searcher see what was wrong.


I had one where I strongly suspect the disk at a bridge has been buried or removed, and someone had reported a recent Found. I filed a Not Found and mentioned that there is a bronze plug in a nearby culvert headwall at almost exactly the scaled coordinates. That's what I suspect was found instead of the disk.


Maybe there was at one time a bridge on the main road where that culvert now sits, or maybe the bridge still standing on the side road once had a concrete wing wall. Either way, I couldn't find a likely spot for a disk, so I recorded the fact that the disk was not apparent. If I'm wrong, then the next person can record a better To Reach.

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I think both reports are completely flawed for a simple reason. To me, recovering a tri-station requires a statement about each disk mentioned in the description, so even if I found the station and all reference marks exactly where they were described I would say "Station and all reference marks recovered as described". This shows that I searched for and located, correctly, all of the marks. A report for a tri-station with no text implies to me that either only the station was searched for and found, or that the wrong mark may have been found as the station, which is what happened in your case. See for example KW3078.


To make your situation worse, the recoverer described the station as suitable for satellite observations. Since he/she did not recover the actual station, that may or may not be true. In fact, from the description I suspect it is NOT true, as the station is described as being at the edge of the woods. This "false positive", where something that does not exist is described as existing, may result in a survey team showing up at that location ready to use MIDLOTHIAN 2 as a satellite point and discovering they cannot, resulting in lost time and money. Since the RM has no listed NGS PID its exists only as a reference point and not a valid survey point, so it cannot be used for anything but to locate the station.

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A report for a tri-station with no text implies to me that either only the station was searched for and found, or that the wrong mark may have been found as the station, which is what happened in your case. See for example KW3078.

Here's another example SY4905. The mark itself is found easily enough, but when reference marks are also listed, I feel an obligation to look for them and reporting them accordingly. I think the RMs and the AZ for SY4905 all fallen victim to the rampant development of Seattleland.


So now my question: Is SY4905 considered usable without the RMs?



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I think the RM's are just there to a) primarily help find the station and B) perhaps also help check that the station has not been shifted in position. If someone uses the mark for serious business they aren't going to set up over the RMs.


If the main station is easily found (with your updated description), and nothing calls into question its stability, then it should be just as usable without any reference marks.


A good description should probably mention the condition of each disk, or something like "RM5 not found in a quick search". But just because the RM isn't there don't hold back on reporting the main mark as found.


Edit: dad-gum smiley crept in in place of punctuated text.

Edited by Bill93
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When I am using an NGS Datasheet in the course of my job, and I get to the Narrative texts, I read through them all... I put a lot of credence on the Monumenting Narrative and then I think of the subsequent recoveries of he station as a history of the times it has been searched for. I know thing change with the times and that people can make mistakes in both interpretation and betting mixed up during the redefinition of describing features. It is easy to do.


It is not uncommon to find that in the subsequent narratives, a lot of new and helpful information has been added to the narrative listings that aid us further and easier than the original description. Is is a case by case thing, and is just a record of that localities evolution.


It is also safe to say that what we find that seem like errors, may have been true for a time, and now no longer is. Everything, and I mean everything is Temporal, no matter how semipermanent we attempt to make it.


So I look for what is changed and what is still the same. The things that seem to have changes become suspect to me, for they may have changed or they may be errors. Things that have remained the same through many observations are likely still the same.


These Narrative descriptions really are a form of story problem, They hold Truisms and falsehoods and a lot of peripheral info. We really have to work each of them as a puzzle having it's own merits. The trick is that at the start, we do not know what the merits are. I once recovered a second order horizontal station which had been described in so many ways that it would have taken over 2 hours to confirm them all. The Mark had two reference marks monumented in drill holes along a Curb, and though they both pointed at the Buried Station, there was nothing in the Narrative that detailed how to find the station using the reference marks. For instance. How would you find the Station with two tape measures used a swing lines from the Reference marks, which would be the most accurate and easiest way to find the buried station. It seemed odd to me that the station was never referenced to the 2 objects which were truly placed to help it be found. I can assure you that the description has been updated now.


So in the end, After I have found the station and if I find errors in the subsequent narratives, I simply correct them by referring to the errors directly and I also confirm what I actually did measure while I was there. I may also choose to confirm again what has always been so the next user knows which of the old descriptors are still remaining relevant to the description when I was here. If time is kind to the locality, hopefully I have left them something they can use.



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Yes, it is usable. As stated in other postings the main station is the one that will be used for surveying purposes. Only it and the azi mark have PIDs (in this case... some RMs have their own PID so are usable for vertical surveying), so they are the only stations that can be used for surveying. The RMs are there to help locate the station and to recreate it if it is lost. If the station is undisturbed it is usable.


Your references to the RMs in the recovery are good--you put in what you did and what you found. That allows someone looking for the mark(s) in the future to use your research if they want to locate them, or gives them some reasoning why the stations cannot be found.



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