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The survey of Harney Peak (now Black Elk Peak) was performed to determine an accurate elevation of the peak. This elevation is compared with the historical elevation long associated with Harney Peak. Jerry Penry of Lincoln, Nebraska, and Kurt Luebke of Missoula, Montana, are both South Dakota licensed land surveyors with over 60 years of combined experience. Paul Horsted is a notable historian and author from Custer, South Dakota. They were assisted by rock climber Daryl Stisser of Custer, Jenny Stukel of Lincoln, and Camille and Anna Marie Riner of Custer. The equipment used to determine our results are high-grade surveying instruments that greatly surpass the capabilities of handheld devices such as receivers or cell phone aps that have come into common practice by the general public.

Two geodetic bench marks near Hill City were used in conjunction with this survey. These bench marks were placed in 1934 by the U. S. Coast & Geodetic Survey (USC&GS) along the former railroad, now used as the Mickelson Trail. These bench marks are designated "A 178" and "C 178". With bench mark "C 178" set vertically into the face of a rock outcropping, it was necessary to place a new point in an open area where GPS equipment could be used. This new monument was designated "Bench Mark No. 1" for this survey. A closed loop level run was made to this point in order to transfer an elevation from "C 178". This work was performed by Jerry and Jenny Stukel Penry on the morning of September 15, 2016. The new point is approximately 100 yards south of the Mickelson Trail bridge over Highway 16 and approximately 10 yards east of the highway.

During the late morning of September 15, 2016, Jerry Penry and Paul Horsted hiked to the Lookout Tower on Harney Peak. The survey began by setting up a level and randomly assigning an elevation of 100.00 feet to USC&GS triangulation station "HARNEY 1950". A Sokkia GSR2700ISX receiver was placed over the triangulation station. Levels were run to Reference Mark No. 1, Reference Mark No. 2, Camera Point 7, and to a drill hole in the granite which once marked the center of a former airway beacon tower. Levels were carried east to the area of the Lookout Tower. The top of a 3/4" diameter iron bolt in granite was found 20.2' west of the northwest corner of the Lookout Tower and used as a bench mark for work around the tower.

The level was then set up on the rock just southeast of the Lookout Tower so the crosshair was even with the highest point on "McGillicuddy Peak" located 317' south of the Lookout Tower. A reading was taken on the iron bolt and a difference of 12.12' was determined. Levels were run up the south stairs to the highest finished concrete floor of the Lookout Tower where an elevation was determined at the exact center of the tower floor. Levels were run in reverse back to the triangulation station to assure that the work was accurate. This completed the work done on September 15, 2016.

On the morning of September 16, 2016, Kurt Luebke and Jerry Penry placed a Trimble 5800 GPS receiver on "Bench Mark No. 1" and another one on "A 178" near Hill City. The entire group then met at the Sylvan Lake parking lot and made the climb to Harney Peak. Paul and Daryl began climbing McGillicuddy Peak with assistance from Anna Marie and Camille below. Kurt and Jerry went to the area of the triangulation station while Jenny stayed inside the Lookout Tower with the prism rod. Kurt set a Trimble R8 Model 3 GPS receiver on the triangulation station. Jerry set up a Sokkia SET-3 total station over the drill hole at the former airway beacon tower site. Due to strong wind, the setup had to be made low to the ground.

Kurt began obtaining elevations on the various points with the Trimble GPS RTK as a check of the elevations previously done with levels by Jerry and Paul. Jerry took vertical angles readings to points on the Lookout Tower where Jenny was located and to the top of McGillicuddy Peak where Paul and Daryl were positioned. Jerry also performed a function with the total station known as "remote elevation" as a check on the vertical angles to the top of the Lookout Tower and to the tip of the lightning rod. A direct line of sight from the drill hole to the center of the Lookout Tower was made by sighting through the open window on the west side of the Lookout Tower to Jenny holding the prism rod on the floor of the center of the tower. Paul used a small pocket prism on McGillicuddy Peak which Jerry obtained a distance to from the drill hole. This work verified the elevation of this peak from the previous day.

Determinations were made by Jerry to the highest natural rock on Harney Peak near the Lookout Tower by vertical angle. Kurt simultaneously used RTK as a check. All work done on Harney Peak was completed using different methods including differential levels, levels, multiple static GPS occupations, and RTK observations to ensure that the determined elevations were accurate.

Jerry Penry taking notes on Day 1 of the survey on September 15, 2016. - Paul Horsted photo.

THE RESULTS

The elevations below are represented in feet on the North American Vertical Datum of 1988 (NAVD88).

LOOKOUT TOWER
7257.20' = Top of Roof (outside) of Lookout Tower.   [PHOTO]
7262.30' = Tip of Lightning Rod on Lookout Tower.   [PHOTO]

NATURAL ROCK
7231.32' = Highest remaining natural rock on Harney Peak near the Lookout Tower.   [PHOTO]
7229.41' = Highest remaining natural rock on "McGillicuddy Peak".   [PHOTO]

SURVEY POINTS
7213.21' = Triangulation Station "HARNEY 1950".   [PHOTO]
7208.27' = Reference Mark No. 1.   [PHOTO]
7209.48' = Reference Mark No. 2.   [PHOTO]
7209.46' = Camera Point No. 7.   [PHOTO]
7215.71' = Airway Beacon Drill Hole.   [PHOTO]
7217.29' = Bolt in granite near Lookout Tower.   [PHOTO]

The final elevations for all points are referenced from USC&GS triangulation station "HARNEY 1950". The elevation for this point, a bronze disk in granite, is determined to be 7213.21 feet NAVD88. The basis for this elevation is from "Bench Mark No. 1" which was established by a closed loop of differential levels from USC&GS Bench Mark "C 178" for this survey. This would be the best realization of NAVD88. The accuracy of the ellipsoid height is determined to be 0.02 to 0.03 meters (0.07 to 0.10 feet). From the National Geodetic Survey toolkit, it estimates that the accuracy of the geoid height at station "HARNEY 1950" is 0.047 meters (0.154 feet). Add these two factors together, 0.047 meters + 0.025 meters = 0.072 meters (0.236 feet) which is virtually identical to the elevation difference of 0.067 meters (0.236 feet) that was observed by comparing the Continuously Operating Reference Station (CORS) derived elevation obtained through Online Positional User Service (OPUS) which processed the GNSS data from "Bench Mark No. 1".

The difference in elevation of the various points obtained by differential leveling on September 15, 2016, and by using GPS RTK on September 16, 2016, as a secondary check, did not vary by more than 0.01 feet between any two points. The only exception is the highest natural rock on the north side of the Lookout Tower where measurements varied by only 0.04 feet. The final elevations for RM No. 1, Reference Mark No. 2, Camera Point No. 7, the Airway Beacon Drill Hole, and the bolt in the granite near the Lookout Tower were computed by using the elevation from this point as determined by the differential leveling. The final elevation of the highest natural rock surface near the Lookout Tower is that elevation determined by RTK.

The final elevations for the top of the Lookout Tower roof and the tip of the lightning rod on the Lookout Tower roof were determined by adding the difference in elevations from the elevation of the Airway Beacon Drill Hole to what was determined by vertical angle with the total station from the Drill Hole. The final elevation determined for the highest natural rock on "McGillicuddy Peak" was determined by adding the difference in elevation from the Bolt near the Lookout Tower as determined by differential levels. This checks within 0.01 feet when compared to the elevation determined by vertical angle from the Airway Beacon Drill Hole.

NOTES FROM THE SURVEY

The location of the Drill Hole where the total station was set up. This was the center of the former Airway Beacon Tower.

Vertical angle method used to determine the elevations for the roof and lightning rod.
The elevations are assumed and based upon the triangulation station being 100.00 and prior to final adjustment.

Vertical angle method used to determine the elevation for the highest natural rock by the control tower.
The elevations are assumed and based upon the triangulation station being 100.00 and prior to final adjustment.

PHOTOS FROM THE SURVEY

September 15, 2016

Our campsite for three nights at the Sylvan Lake Campground. - Jerry Penry photo.

Jerry Penry looking for a good vantage point to set up the level. - Paul Horsted photo.

Paul Horsted on Camera Point 7 with the level rod located to the far west end of the peak. - Paul Horsted photo.

Jerry Penry measuring the diameter of the drill hole at the center of the former Airway Beacon Tower. - Paul Horsted photo.

Paul Horsted and Jerry Penry inside the Lookout Tower obtaining an elevation on the highest finished floor - Paul Horsted photo.

Jerry Penry setting up the level so the crosshairs match the top of McGillicuddy Peak. - Paul Horsted photo.

A Sokkia GSR2700ISX receiver set over the "Harney" triangulation station. - Jerry Penry photo.

A plumb bob centered over the center of the triangulation station on Harney peak. - Jerry Penry photo.

September 16, 2016

Bench Mark "C 178" south of Hill City in the granite rock. - Jerry Penry photo.

Bench mark "C 178". - Jerry Penry photo.

GPS equipment on "Bench Mark No. 1" south of Hill City. - Jerry Penry photo.

A new point established for this survey "Bench Mark No. 1" - Jerry Penry photo.

Kurt Luebke setting up the Trimble GPS receiver over bench mark "A 178" north of Hill City. - Jerry Penry photo.

Bench Mark "A 178". - Jerry Penry photo.

Daryl Stisser climbing up McGillicuddy Peak. - Paul Horsted photo.

Anna Marie Riner assisting from the base of McGillicuddy Peak. - Paul Horsted photo.

Kurt Luebke (left) on Camera Point 7 and Jerry Penry on the drill hole - Paul Horsted photo.

Paul Horsted on McGillicuddy Peak aiming the prism toward Jerry Penry on the airway beacon tower drill hole. - Paul Horsted photo.

Paul Horsted on the highest point on McGillicuddy Peak. - Paul Horsted photo.

Paul Horsted on McGillicuddy Peak. - Paul Horsted photo

Daryl Stisser and Paul Horsted on McGillicuddy Peak. - Paul Horsted photo.

Paul Horsted, Jerry Penry, and Kurt Luebke on Harney Peak. - Paul Horsted photo.

Camille Riner and Paul Horsted posing near the Lookout Tower. - Paul Horsted photo.

McGillicuddy Peak as seen from the Lookout Tower. - Paul Horsted photo.

Kurt Luebke taking a photo of himself with a nearby mountain goat. - Kurt Luebke photo.

Jerry Penry and Kurt Luebke taking time for a photo in strong wind. - Kurt Luebke photo.

A mountain goat passes near the triangulation station. - Kurt Luebke photo.

Jerry Penry set up over the drill hole. Paul Horsted at far right is on top of McGillicuddy Peak. - Kurt Luebke photo.

Jerry Penry on the drill hole with a mountain goat nearby.

Jerry Penry with the total station over the drill hole while Kurt Luebke prepares to set up GPS equipment on the triangulation station.

A visitor on Harney Peak.

Harney Peak's Lookout Tower with McGillicuddy Peak on the right. - Jerry Penry photo.

The curious mountain goat on Harney Peak. - Jerry Penry photo.

The total station set up over the drill hole with McGillicuddy Peak in the background. - Jerry Penry photo.

Paul Horsted and Daryl Stisser on McGillicudy Peak. - Jerry Penry photo.

Kurt Luebke (left) and Jerry Penry at the total station set up over the drill hole at the former Airway Beacon Tower.
Paul Horsted and Daryl Stisser are on McGillicuddy Peak as shown by the arrow. - Jerry Penry photo.

Kurt Luebke obtaining RTK positions on the north side of the Lookout Tower. - Jerry Penry photo.

The total station over the drill hole looking through the window on the Lookout Tower. - Jerry Penry photo.

Jenny Stukel seeking some shelter in the rocks on a cold and windy day. - Jerry Penry photo.

Mountain goat on Harney Peak. - Jerry Penry photo.

Kurt Luebke packing equipment out after a day of surveying - Jerry Penry photo.

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