Details for Benchmark: HS3978
N 37° 42.100 W 121° 52.750 (NAD 83)
Coordinates may not be exact. Altitude is VERTCON and location is SCALED. (more info)
- In ALAMEDA county, CA View Original Datasheet
- P 24 N
- Marker Type:
- set into the top of a round concrete monument
- May hold, but of type commonly subject to surface motion.
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Documented History (by the NGS)
|Unknown by CGS (MONUMENTED)
|01/01/1964 by NGS (GOOD)
|DESCRIBED BY NATIONAL GEODETIC SURVEY 1964
4.8 MI NW FROM PLEASANTON. A COPPER NAIL AND WASHER SET IN THE SIDE OF THE CONCRETE POST SURROUNDING THE ROD. FOR DESCRIPTION SEE P 24 ABOVE.
|01/01/1965 by NGS (GOOD)
|RECOVERY NOTE BY NATIONAL GEODETIC SURVEY 1965
RECOVERED IN GOOD CONDITION.
- The horizontal coordinates were scaled from a topographic map and have an estimated accuracy of +/- 6 seconds.
- The NAVD 88 height was computed by applying the VERTCON shift value to the NGVD 29 height (displayed under SUPERSEDED SURVEY CONTROL.) The vertical order pertains to the superseded datum.
- The geoid height was determined by GEOID99.