1 National Geodetic Survey, Retrieval Date = MAY 3, 2005 DE8499 *********************************************************************** DE8499 HT_MOD - This is a Height Modernization Survey Station. DE8499 DESIGNATION - GPS CONTROL PT 45 DE8499 PID - DE8499 DE8499 STATE/COUNTY- CA/CONTRA COSTA DE8499 USGS QUAD - BYRON HOT SPRINGS (1968) DE8499 DE8499 *CURRENT SURVEY CONTROL DE8499 ___________________________________________________________________ DE8499* NAD 83(1998)- 37 48 58.99590(N) 121 38 53.33947(W) ADJUSTED DE8499* NAVD 88 - 49.62 (meters) 162.8 (feet) GPS OBS DE8499 ___________________________________________________________________ DE8499 EPOCH DATE - 2000.86 DE8499 X - -2,647,100.445 (meters) COMP DE8499 Y - -4,294,709.203 (meters) COMP DE8499 Z - 3,889,374.997 (meters) COMP DE8499 LAPLACE CORR- -2.87 (seconds) DEFLEC99 DE8499 ELLIP HEIGHT- 17.55 (meters) (11/27/02) GPS OBS DE8499 GEOID HEIGHT- -32.10 (meters) GEOID03 DE8499 DE8499 HORZ ORDER - B DE8499 ELLP ORDER - FOURTH CLASS I DE8499 DE8499.The horizontal coordinates were established by GPS observations DE8499.and adjusted by the National Geodetic Survey in November 2002. DE8499.This is a SPECIAL STATUS position. See SPECIAL STATUS under the DE8499.DATUM ITEM on the data sheet items page. DE8499.The horizontal coordinates are valid at the epoch date displayed above. DE8499.The epoch date for horizontal control is a decimal equivalence DE8499.of Year/Month/Day. DE8499 DE8499.The orthometric height was determined by GPS observations and a DE8499.high-resolution geoid model using precise GPS observation and DE8499.processing techniques. DE8499 DE8499.The X, Y, and Z were computed from the position and the ellipsoidal ht. DE8499 DE8499.The Laplace correction was computed from DEFLEC99 derived deflections. DE8499 DE8499.The ellipsoidal height was determined by GPS observations DE8499.and is referenced to NAD 83. DE8499 DE8499.The geoid height was determined by GEOID03. DE8499 DE8499; North East Units Scale Factor Converg. DE8499;SPC CA 3 - 646,714.224 1,898,913.886 MT 0.99992983 -0 42 10.6 DE8499;SPC CA 3 - 2,121,761.58 6,230,019.97 sFT 0.99992983 -0 42 10.6 DE8499;UTM 10 - 4,186,303.925 618,986.914 MT 0.99977438 +0 49 44.3 DE8499 DE8499! - Elev Factor x Scale Factor = Combined Factor DE8499!SPC CA 3 - 0.99999725 x 0.99992983 = 0.99992708 DE8499!UTM 10 - 0.99999725 x 0.99977438 = 0.99977163 DE8499 DE8499 SUPERSEDED SURVEY CONTROL DE8499 DE8499.No superseded survey control is available for this station. DE8499 DE8499_U.S. NATIONAL GRID SPATIAL ADDRESS: 10SFG1898786304(NAD 83) DE8499_MARKER: DD = SURVEY DISK DE8499_SETTING: 50 = ALUMINUM ALLOY ROD W/O SLEEVE (10 FT.+) DE8499_STAMPING: PT 45 LS 5672 1990 DE8499_MARK LOGO: CA-013 DE8499_PROJECTION: RECESSED 15 CENTIMETERS DE8499_MAGNETIC: N = NO MAGNETIC MATERIAL DE8499_STABILITY: B = PROBABLY HOLD POSITION/ELEVATION WELL DE8499_SATELLITE: THE SITE LOCATION WAS REPORTED AS SUITABLE FOR DE8499+SATELLITE: SATELLITE OBSERVATIONS - March 22, 2005 DE8499_ROD/PIPE-DEPTH: 31 meters DE8499 DE8499 HISTORY - Date Condition Report By DE8499 HISTORY - 1990 MONUMENTED LOCSUR DE8499 HISTORY - 20050322 GOOD CA-013 DE8499 DE8499 STATION DESCRIPTION DE8499 DE8499'DESCRIBED BY LOCAL SURVEYOR (INDIVIDUAL OR FIRM) 1990 (RZ) DE8499'THE STATION IS LOCATED ABOUT 13 MI (20.9 KM) NORTHWEST OF TRACY AAND DE8499'3.5 MI (5.6 KM) SOUTHWEST OF BYRON. TO REACH THE STATION FROM THE DE8499'INTERSECTION OF BYRON HIGHWAY AND CAMINO DIABLO IN BYRON, GO SOUTH ON DE8499'BYRON HIGHWAY FOR 0.5 MI (0.8 KM) TO A SIDE ROAD RIGHT, BYRON HOT DE8499'SPRINGS ROAD. TURN RIGHT AND GO SOUTHWEST ON BYRON HOT SPRINGS ROAD DE8499'FOR 0.9 MI (1.4 KM) TO A SIDE ROAD RIGHT, ARMSTRONG ROAD. TURN RIGHT DE8499'AND GO NORTHWEST AND THEN SOUTHWEST FOR 2.0 MI (3.2 KM) TO THE END OF DE8499'PAVEMENT. CONTINUE SOUTHWEST AND THEN NORTHWEST ON ARMSTRONG ROAD FOR DE8499'0.9 MI (1.4 KM) TO THE STATION ON THE LEFT. THE STATION IS 9.0 M DE8499'(29.5 FT) SOUTH OF THE CENTERLINE OF ARMSTRONG ROAD, 1.3 M (4.3 FT) DE8499'NORTHWEST OF THE EAST OF TWO WOODEN FENCE POSTS, 1.0 M (3.3 FT) DE8499'NORTHEAST OF THE WEST OF THE TWO POSTS AND 0.5 M (1.6 FT) NORTH OF THE DE8499'FENCE AND A YELLOW CARSONITE WITNESS POST. IT IS SET INSIDE AN 8 IN DE8499'PVC PIPE WITH CAP. IT IS ABOUT 0.15 M (0.49 FT) BELOW THE TOP OF THE DE8499'PIPE. DE8499 DE8499 STATION RECOVERY (2005) DE8499 DE8499'RECOVERY NOTE BY CONTRA COSTA COUNTY CALIFORNIA 2005 (LL) DE8499'RECOVERED IN GOOD CONDITION.