Details for Benchmark: HV8455
N 38° 46.964 W 077° 24.022 (NAD 83)
Coordinates may not be exact. Altitude is VERTCON and location is ADJUSTED. (more info)
- In FAIRFAX county, VA View Original Datasheet
- Marker Type:
- survey disk
- surrounded by a mass of concrete
- Mark of questionable or unknown stability.
Benchmarks may be on private property or in dangerous locations. Obey local laws. By using the services on Geocaching.com you agree to this disclaimer.
Documented History (by the NGS)
|01/01/1969 by VA-059 (MONUMENTED)
|DESCRIBED BY FAIRFAX COUNTY VIRGINIA 1969 (HWC)
THE STATION IS APPROXIMATELY 3/4 MILE WEST OF THE TOWN OF CLIFTON IN THE POWER LINE EASEMENT.
TO REACH THE STATION FROM CLIFTON PROCEED NORTHWEST ALONG CLIFTON ROAD, ROUTE 645, TO COMPTON ROAD, ROUTE 658. WESTERLY ALONG SAME 1500 FEET TO DIRT ROAD LEFT, THEN WITH MEANDERS OF ROAD GENERALLY SOUTH TO POWER LINE, THEN WITH POWER LINE APPROXIMATELY 500 FEET TO TOP OF HILL, 111.5 FEET NORTHEAST OF THE NORTHEAST CORNER OF A STEEL TOWER NUMBER 207/63, 55.2 FEET SOUTHWEST OF POLE NUMBER 57/75, SET IN A CONCRETE MASS.
STATION IS A STANDARD FAIRFAX COUNTY DISK STAMPED---HEAD 1969---.
THE AZIMUTH MARK USED IS STATION IVAKOTA AZ, APPROXIMATELY 3500 FEET NORTHWEST OF STATION HEAD ALONG POWER LINE.
THE STATION IS A FILED + ON THE BASE PLATE OF TOWER NUMBER 207/60.
|01/01/1975 by VA-059 (GOOD)
|RECOVERY NOTE BY FAIRFAX COUNTY VIRGINIA 1975 (EYB)
THE STATION AND AZIMUTH MARK WERE FOUND IN GOOD CONDITION. SEE FAIRFAX COUNTY TAX MAP 75-3, REVISED TO 1-1-76.
|01/01/1977 by VA-059 (GOOD)
|RECOVERY NOTE BY FAIRFAX COUNTY VIRGINIA 1977 (EYB)
THE STATION AND AZ MK WERE RECOVERED IN GOOD CONDITION AS PER THE ORIGINAL DESCRIPTION.
|01/01/1978 by VA-059 (GOOD)
|RECOVERY NOTE BY FAIRFAX COUNTY VIRGINIA 1978 (EYB)
THE STATION WAS RECOVERED IN GOOD CONDITION AS DESCRIBED
- The horizontal coordinates were established by classical geodetic methods and adjusted by the National Geodetic Survey in November 1994.
- The NAVD 88 height was computed by applying the VERTCON shift value to the NGVD 29 height (displayed under SUPERSEDED SURVEY CONTROL.)
- The Laplace correction was computed from DEFLEC99 derived deflections.
- The geoid height was determined by GEOID99.