Details for Benchmark: MF1258
N 41° 42.033 W 088° 00.433 (NAD 83)
Coordinates may not be exact. Altitude is ADJUSTED and location is SCALED. (more info)
- In DU PAGE county, IL View Original Datasheet
- LEMONT 103 D CO
- Marker Type:
- bench mark disk
- aluminum alloy rod
- Probably 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
2.0 MI NORTH FROM LEMONT. 2.0 MILES NORTH OF LEMONT, 1.25 MILES SOUTH ALONG LEMONT ROAD FROM THE JUNCTION OF INTERSTATE 55 TO MARK ON LEFT, AT THE NORTHEAST CORNER OF A T-INTERSECTION WITH 103RD STREET, 30.0 FEET EAST OF LEMONT ROAD EAST EDGE OF PAVEMENT, AND 50.0 FEET NORTH OF ARGONNE NATIONAL LABORATORY OCCUPIED SOUTH LINE, AN ALUMINUM ALLOY ROD DRIVEN 10.0 FEET AND ENCASED WITH PLASTIC SLEEVE AND CAP.
|04/20/1996 by USPSQD (POOR)
|RECOVERY NOTE BY US POWER SQUADRON 1996
MARK RECOVERED IN POOR 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.