Date: March 27, 2021
Distance: 14.11 miles
Total Elapsed Time: 6h 24m
Total Moving Time: 5h 19m
Summit Elevation: 4,029 feet
Elevation Gain: 2,982 feet
Trailhead: Sasquatch Trail, Pamo Road, Ramona
Previous Ascents: March 22, 2020
Notes:
Peakbagger Peaks - 1, Survey Marks - 3 (stems only)
Objective: Big Black Mountain Survey Marks
One of my first steps in prepping to recover survey marks is to check the National Geodetic Survey (NGS) Explorer online to see if the marks are registered in their database. If they are, I review all the related datasheets and print the ones I need. The above image is a composite I created from extracts of the Black Mountain datasheet.
Section A: The basic metadata is self-explanatory, the Current Survey Control data that immediately follows the metadata contains the coordinates to the mark. For this mark, the coordinates are "Adjusted" which means they have a greater degree of reliability or accuracy. On many datasheets, you will find the term "Scaled", which is likely the least accurate as the location was determined from a map as opposed to first-hand observation methods. I plot these and add them to GAIA GPS as waypoints so I'll have this information readily available when I'm on the trail, regardless of cellphone coverage.
Section B: This is referred to as the "Box Score" because of the ASCII text symbols that outline it on the datasheet. As I've mentioned in previous posts, this section is VERY helpful in understanding the position of all the other reference objects in relation to the subject of this datasheet (in this case, PID: DX5019, the Black Mountain Station Disc).
Standing at the station disc looking to True North (TN), each reference mark is listed in order by its Geodetic Azimuth or its compass position based on TN as you go around the compass clockwise. That information coupled with the distance ought to put you very close to the mark's location, then it just comes down to understanding how marks are generally set to look for the probable location.
Section C: There can be a lot of information in this section, generally starting out with the description of the mark and original directions to reach it. The NGS has specific instructions on how to write descriptions used in this section and the original directions can be fun to read (and sometimes near impossible to follow 🤣). Subsequent recovery attempts may clarify directions to include new or changed landmarks, as well as the results of the attempt.
Sometimes, this information can be confusing and contradictory so it's a good idea to read through all of them and look for consistent threads of information. In the excerpt that I've chosen above, it's very clear that the original discs are gone and only the brass stems remain.
Triangulation Station - DX5019
When I completed Big Black Mountain last year, I had found the remains of RM 1 and thought that it was the Station Disc, when looking back at my GPX track and photos from that trip, I never even explored the area behind the HPWREN Tower structure, after all, it just looked like a pile of rocks. Had I gone about 15 feet further, I likely would have found this.
Today I knew what to look for from the information in the datasheet, but I took that one step further.
Yesterday I was online looking at the San Diego County Survey Record System and had viewed a series of survey maps and notes from surveys in the Ramona area. I came across one completed in March of 2000 that included monument sketches and descriptions of the monuments recovered on the survey.
The surveyor had recovered what was left of the Station Disc and the RM 1. (but didn't record finding RM 2!)
The 2003 recovery description on the NGS datasheet (section C in the image above) confirmed that all three marks at the summit had been vandalized and only the stems remained. The old Fire Lookout Tower (DX5020 Black Mountain Lot) was no longer there. I was unable to locate a photo of, or any details about, the original fire lookout tower online.
Reference Marks - CE9805 and CE9805
Previously, I would have labeled these marks as lost/destroyed as the brass discs are all clearly gone. However, you could make an argument that they were all recovered, just in very poor condition. As a layman, I wonder if the presence of the center portion of the disc (with the triangle symbol) means the station disc could still be used as a survey point? (I would imagine yes, but I'm not sure). Likewise, finding the center points of the stems on the reference marks would seem to provide some measure of accuracy for them as well 🤷🏻♂️.
Oh yeah, it was a hike too...
LOL, while the main focus of my trip today was to find these survey marks, it was also a great hike. One of my friends is crushing the San Diego 100 Peak Challenge and this was peak number 94 of 100 on his quest. 👍🏻
I completed this Challenge last year, summiting my 100th Peak on October 24, 2020, Phil is on track to complete all 100 Peaks in 100 days! 😳
We got an early start hitting the trail at 0630, and maintained a good pace to the summit covering the 7-mile trip and 3,000+ feet of gain in under 3 hours. The weather was ideal, almost cold at the start, windy and cool at the summit, and warming slightly as we descended. The views of Pamo Valley are always spectacular!
The route is almost entirely on a fire road, with the last quarter-mile on an obvious Use Trail. While the old Fire Lookout Tower is gone, there is a High-Performance Wireless Research & Education Network (HPWREN) station at the summit (RM 2 was set in the NNW corner of the tower footing). This was pretty cool as we showed up on the video (South-looking Camera) and still photos taken with the camera! Click to view the video on the HPWREN Site.
