Details for Benchmark: MF1257
N 41° 42.650 W 088° 00.383 (NAD 83)
Coordinates may not be exact. Altitude is ADJUSTED and location is SCALED. (more info)
- In DU PAGE county, IL View Original Datasheet
- ARGONNE D CO
- Marker Type:
- metal rod
- stainless steel rod in sleve
- Most reliable and expected to hold position/elevation well.
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Documented History (by the NGS)
|01/01/1983 by MARCHE (MONUMENTED)
|DESCRIBED BY MARCHESE AND SONS 1983
2.5 MI NORTH FROM LEMONT. 2.5 MILES NORTH OF LEMONT, 2.8 MILES SOUTH OF WOODRIDGE AND IS ON THE EAST SIDE OF LEMONT ROAD, 0.4 MILE SOUTH ALONG LEMONT ROAD FROM THE JUNCTION OF INTERSTATE HIGHWAY 55 AND LEMONT ROAD TO MARK ON LEFT, AT THE SOUTHEAST CORNER OF THE INTERSECTION WITH WESTGATE ROAD TO ARGONNE NATIONAL LABORATORY, 131.9 FEET SOUTH-SOUTHEAST OF SOUTHWEST BOLT IN BASE OF STREETLAMP STANDARD, 47.2 FEET EAST-SOUTHEAST OF SOUTHWEST CORNER OF CONCRETE BASE OF STREET SIGN POST, 150.0 FEET NORTH OF THE NORTHEAST CORNER OF A CONCRETE FOUNDATION FOR A BRICK BUILDING, A STAINLESS STEEL ROD IN SLEEVE ENCASED IN CAST ALUMINUM CYLINDER, CYLINDER COVER IS FLUSH WITH SURROUNDING GROUND. NOTE--NO DEPTH FOR ROD WAS GIVEN.
|04/20/1996 by USPSQD (GOOD)
|RECOVERY NOTE BY US POWER SQUADRON 1996
RECOVERED IN GOOD CONDITION.
- The horizontal coordinates were scaled from a topographic map and have an estimated accuracy of +/- 6 seconds.
- The orthometric height was determined by differential leveling and adjusted by the National Geodetic Survey in June 1991.
- The geoid height was determined by GEOID99.
- The dynamic height is computed by dividing the NAVD 88 geopotential number by the normal gravity value computed on the Geodetic Reference System of 1980 (GRS 80) ellipsoid at 45 degrees latitude (g = 980.6199 gals.).
- The modeled gravity was interpolated from observed gravity values.