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Details for Benchmark: AA2135

N 41° 01.961 W 106° 41.071 (NAD 83)

Altitude: 10970

Coordinates may not be exact. Altitude is GPS OBS and location is ADJUSTED. (more info)

Location:
In CARBON county, WY View Original Datasheet
Designation:
SUMPTER
Marker Type:
horizontal control disk
Setting:
in a boulder
Stability:
May hold, but of type commonly subject to surface motion.

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Documented History (by the NGS)

01/01/1993 by USFS (MONUMENTED)
DESCRIBED BY US FOREST SERVICE 1993 (GWA) NOTE - A FOUR WHEEL DRIVE VEHICLE IS REQUIRED FOR THE LAST 0.3 KM (0.20 MI) OF THE ROAD TO THE STATION IN GOOD CONDITIONS, IN BAD CONDITIONS, A FOUR WHEEL DRIVE VEHICLE IS A MUST AND STILL MIGHT NOT GET YOU THERE. THE 31.6 KM (19.65 MI) DISTANCE OF THE TO REACH TAKES ABOUT 1 HOUR TO COVER. STATION IS LOCATED ABOUT 41 KM (25.45 MI) WEST OF MOUNTAIN HOME, 22 KM (13.65 MI) SOUTHEAST OF ENCAMPMENT, 3.75 KM (2.35 MI) NORTH OF THE WYOMING-COLORADO STATE LINE, ON BLACKHALL MOUNTAIN, IN THE MEDICINE BOW NATIONAL FOREST. OWNERSHIP--U.S. FOREST SERVICE. TO REACH FROM THE JUNCTION OF STATE HIGHWAYS 70 AND 230 (ON THE NORTH SIDE OF ENCAMPMENT), GO EAST ON HIGHWAY 230 FOR 1.45 KM (0.90 MI) TO A SIDE DIRT ROAD RIGHT. TURN RIGHT, SOUTH, ON BLACKHALL MOUNTAIN ROAD (COUNTY ROAD 211) FOR 4.3 KM (2.65 MI) TO A CATTLEGUARD. CONTINUE AHEAD, SOUTHERLY, FOR 6.1 KM (3.80 MI) TO A CATTLEGUARD AT THE ENTRANCE TO THE MEDICINE BOW NATIONAL FOREST (END OF COUNTY ROAD 211 AND BEGINNING OF FOREST DEVELOPMENT ROAD 409). CONTINUE AHEAD ON FOREST ROAD 409 FOR 1.65 KM (1.00 MI) TO ROAD 409-3A ON THE LEFT. CONTINUE AHEAD FOR 3.85 KM (2.40 MI) TO ROAD 409-1A ON THE LEFT. CONTINUE AHEAD FOR 3.7 KM (2.30 MI) TO ROAD 409-2B ON THE RIGHT. CONTINUE AHEAD FOR 0.05 KM (0.05 MI) TO ROAD 496 ON THE RIGHT. CONTINUE AHEAD FOR 2.6 KM (1.60 MI) TO A FORK (ROAD 404 TO THE LEFT AND 409 TO THE RIGHT). BEAR RIGHT, WESTERLY, ON ROAD 409 FOR 2.75 KM (1.70 MI) TO A FOURWAY INTERSECTION. TURN LEFT AND THEN BEAR RIGHT ON 409 AND GO SOUTHERLY FOR 5.15 KM (3.20 MI) TO THE END OF TRUCK TRAVEL NEAR THE BLACKHALL MTN LOOKOUT TOWER. CLIMB UP ABOUT 25 M (82.0 FT) TO THE STATION NEAR THE SOUTHWEST END OF A ROCKY SPINE. STATION MARK IS A NGS STANDARD HORIZONTAL CONTROL DISK SET IN A DRILL HOLE IN TOP OF A 2 M (6.6 FT) BY 3 M (9.8 FT) EXPOSURE OF A BOULDER. IT IS 42.8 M (140.4 FT) SOUTHWEST OF THE SOUTHEAST CORNER OF BLACKHALL MOUNTAIN LOOKOUT TOWER, AND 2.2 M (7.2 FT) NORTH-NORTHEAST OF A WITNESS POST.

Control Text

  • The horizontal coordinates were established by GPS observations and adjusted by the National Geodetic Survey in October 1994.
  • The orthometric height was determined by GPS observations and a high-resolution geoid model.
  • The X, Y, and Z were computed from the position and the ellipsoidal ht.
  • The Laplace correction was computed from DEFLEC99 derived deflections.
  • The ellipsoidal height was determined by GPS observations and is referenced to NAD 83.
  • The geoid height was determined by GEOID99.