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    SSM     BALGA 60A
    Alternate names : Map ref.: BALGA BG34 3.8
    APREF/NGCA codes: Database number : 104136
    Stamp name:      BAL60A Date established :   01/09/1977
    Physical status : located (The Land Division) Phys. status date :  24/03/2023
    Physical type :    brass plaqueHatch cover type : concrete
    Mark set in :        concreteAccess type : 2 wheel drive
    Geographical CoordinatesMGA2020 Coordinates
    Horizontal datum : GDA2020Zone :             50
    Latitude :     S 31 50 02.95240Easting (m) :   388486.478
    Longitude :  E 115 49 17.60992Northing (m) :  6477341.966
    Convergence :       -0 37 17.93
    Point scale factor : 0.99975336
    Coordinate date :       04/12/2023
    Horizontal method :   Geodetic-TerrestrialCadastral connection : Exists
    Relative horiz. accuracy :       50ppm ** Estimated relative uncertainty to adjacent marks
    Positional uncertainty (m) : 0.022 (95% Confidence level)
    Error Ellipse
    Semi-major axis (m) : 0.023
    Semi-minor axis (m) : 0.022
    Azimuth of semi-major axis (m) : 3 10 12
    ** Projection coordinates are calculated from the geographical coordinates detailed above
    Project Grid - PCG2020Perth Coastal Grid 2020
    Easting (m) :   50463.056
    Northing (m) :  376540.822
    Convergence :       0 0 9.29
    Point scale factor : 0.99999906
    Height Information
    Vertical datum :   AHD71Height type :          Orthometric
    Height (m) :         31.276Height date :          23/06/2008
    Established by :  Dept of Land Admin.State :                    Final
    Vertical method : Spirit LevellingVertical accuracy : 12rootK
    Derived GDA2020 ellipsoidal height (m) : -1.49N-Value (m) :          -32.766
    Geoid model :         AusGeoid2020
    ** Derived GDA2020 ellipsoidal height: h = H + N Interpolation :         Bi-Cubic
    Mark to hatch cover :  
    Mark to ground level : 
    RM Info** Warning: RM azimuths and coordinates are unverified
    ** Azimuth, distance and height difference are relative to main mark
    RM1 Phys. status : located (Nastech (WA) Pty Ltd) Date :   28/07/2009
    Phys. type :    spikeSet in : concrete
    Azimuth :           347 43 7Type :   True azimuth
    Distance (m) :    2.293Type :   Horizontal
    Height diff. (m) : -0.256Type :   Spirit Levelling
    RM to GL (m) :   None
    RM2 Phys. status : located (Nastech (WA) Pty Ltd) Date :   28/07/2009
    Phys. type :    spikeSet in : concrete
    Azimuth :           83 12 47Type :   True azimuth
    Distance (m) :    1.477Type :   Horizontal
    Height diff. (m) : -0.241Type :   Spirit Levelling
    RM to GL (m) :   None
    RM3 Phys. status : established Date :   01/09/1977
    Phys. type :    spikeSet in : concrete
    Azimuth :           167 43 7Type :   True azimuth
    Distance (m) :    3.361Type :   Horizontal
    Height diff. (m) : -0.349Type :   Spirit Levelling
    RM to GL (m) :   None
    RM4 Phys. status : destroyed Date :   24/05/1988
    Phys. type :    spikeSet in : concrete
    Azimuth :           253 38 47Type :   True azimuth
    Distance (m) :    3.260Type :   Horizontal
    Height diff. (m) : NoneType :   
    RM to GL (m) :   None
    RM Position Information** Warning: RM coordinates should be verified prior to use
    ** Coordinates are calculated from reference observations
    ** Coordinate accuracies commensurate with related observations
    RM1
    Geographical CoordinatesMGA2020 Coordinates
    Horizontal datum : GDA2020Zone :             50
    Latitude :     S 31 50 02.87966Easting (m) :   388485.966
    Longitude :  E 115 49 17.59137Northing (m) :  6477344.200
    Project Grid - PCG2020Perth Coastal Grid 2020
    Easting (m) :   50462.569
    Northing (m) :  376543.063
    Height Information
    Vertical datum :   AHD71
    Height (m) :         31.020
    RM2
    Geographical CoordinatesMGA2020 Coordinates
    Horizontal datum : GDA2020Zone :             50
    Latitude :     S 31 50 02.94673Easting (m) :   388487.942
    Longitude :  E 115 49 17.66570Northing (m) :  6477342.156
    Project Grid - PCG2020Perth Coastal Grid 2020
    Easting (m) :   50464.523
    Northing (m) :  376540.997
    Height Information
    Vertical datum :   AHD71
    Height (m) :         31.035
    RM3
    Geographical CoordinatesMGA2020 Coordinates
    Horizontal datum : GDA2020Zone :             50
    Latitude :     S 31 50 03.05902Easting (m) :   388487.228
    Longitude :  E 115 49 17.63711Northing (m) :  6477338.690
    Project Grid - PCG2020Perth Coastal Grid 2020
    Easting (m) :   50463.771
    Northing (m) :  376537.538
    Height Information
    Vertical datum :   AHD71
    Height (m) :         30.927
    RM4
    Geographical CoordinatesMGA2020 Coordinates
    Horizontal datum : GDA2020Zone :             50
    Latitude :     S 31 50 02.98220Easting (m) :   388483.361
    Longitude :  E 115 49 17.49096Northing (m) :  6477341.014
    Project Grid - PCG2020Perth Coastal Grid 2020
    Easting (m) :   50459.928
    Northing (m) :  376539.905
    Height Information
    Vertical datum :   
    Height (m) :         No height available
    Cadastral Connection Fieldbooks
    LG 110126
    LG 110953
    LG 132675
    LG 160816
    Special Notes
    Unknown Daterm1,bal60a,rm3 & bal49 are co-linear
    ATRF 2014
    GDA2020 coordinates are equivalent to ATRF2014@2020.0. ATRF2014 coordinates can be determined by application of the Australian Plate Motion Model. For general and technical information on GDA2020 see http://www.icsm.gov.au/gda2020 and ATRF2014 see http://www.icsm.gov.au/australian-terrestrial-reference-frame.
    View the graphic summary
    SSM     BALGA 60A
    Alternate names : Map ref.: BALGA BG34 3.8
    APREF/NGCA codes: Database number : 104136
    Stamp name:      BAL60A Date established :   01/09/1977
    Physical status : located (The Land Division) Phys. status date :  24/03/2023
    Physical type :    brass plaqueHatch cover type : concrete
    Mark set in :        concreteAccess type : 2 wheel drive
    Geographical CoordinatesMGA94 Coordinates
    Horizontal datum : GDA94Zone :             50
    Latitude :     S 31 50 03.00087Easting (m) :   388485.468
    Longitude :  E 115 49 17.57089Northing (m) :  6477340.462
    Convergence :       -0 37 17.95
    Point scale factor : 0.99975337
    Coordinate date :       09/10/2000
    Horizontal method :   Geodetic-TerrestrialCadastral connection : Exists
    Relative horiz. accuracy :       20ppm ** Estimated relative uncertainty to adjacent marks
    Positional uncertainty (m) : 0.02 (95% Confidence level)
    Error Ellipse
    Semi-major axis (m) : 0.021
    Semi-minor axis (m) : 0.018
    Azimuth of semi-major axis (m) : 175 0 0
    ** Projection coordinates are calculated from the geographical coordinates detailed above
    Project Grid - PCG94Perth Coastal Grid 1994
    Easting (m) :   50462.030
    Northing (m) :  276539.329
    Convergence :       0 0 9.27
    Point scale factor : 0.99999906
    Height Information
    Vertical datum :   AHD71Height type :          Orthometric
    Height (m) :         31.276Height date :          23/06/2008
    Established by :  Dept of Land Admin.State :                    Final
    Vertical method : Spirit LevellingVertical accuracy : 12rootK
    Derived GDA94 ellipsoidal height (m) : -1.418N-Value (m) :          -32.694
    Geoid model :         AUSGeoid09 V1.01
    ** Derived GDA94 ellipsoidal height: h = H + N Interpolation :         Bi-Cubic
    Mark to hatch cover :  
    Mark to ground level : 
    RM Info** Warning: RM azimuths and coordinates are unverified
    ** Azimuth, distance and height difference are relative to main mark
    RM1 Phys. status : located (Nastech (WA) Pty Ltd) Date :   28/07/2009
    Phys. type :    spikeSet in : concrete
    Azimuth :           347 43 7Type :   True azimuth
    Distance (m) :    2.293Type :   Horizontal
    Height diff. (m) : -0.256Type :   Spirit Levelling
    RM to GL (m) :   None
    RM2 Phys. status : located (Nastech (WA) Pty Ltd) Date :   28/07/2009
    Phys. type :    spikeSet in : concrete
    Azimuth :           83 12 47Type :   True azimuth
    Distance (m) :    1.477Type :   Horizontal
    Height diff. (m) : -0.241Type :   Spirit Levelling
    RM to GL (m) :   None
    RM3 Phys. status : established Date :   01/09/1977
    Phys. type :    spikeSet in : concrete
    Azimuth :           167 43 7Type :   True azimuth
    Distance (m) :    3.361Type :   Horizontal
    Height diff. (m) : -0.349Type :   Spirit Levelling
    RM to GL (m) :   None
    RM4 Phys. status : destroyed Date :   24/05/1988
    Phys. type :    spikeSet in : concrete
    Azimuth :           253 38 47Type :   True azimuth
    Distance (m) :    3.260Type :   Horizontal
    Height diff. (m) : NoneType :   
    RM to GL (m) :   None
    RM Position Information** Warning: RM coordinates should be verified prior to use
    ** Coordinates are calculated from reference observations
    ** Coordinate accuracies commensurate with related observations
    RM1
    Geographical CoordinatesMGA94 Coordinates
    Horizontal datum : GDA94Zone :             50
    Latitude :     S 31 50 02.92813Easting (m) :   388484.956
    Longitude :  E 115 49 17.55234Northing (m) :  6477342.697
    Project Grid - PCG94Perth Coastal Grid 1994
    Easting (m) :   50461.542
    Northing (m) :  276541.570
    Height Information
    Vertical datum :   AHD71
    Height (m) :         31.020
    RM2
    Geographical CoordinatesMGA94 Coordinates
    Horizontal datum : GDA94Zone :             50
    Latitude :     S 31 50 02.99520Easting (m) :   388486.932
    Longitude :  E 115 49 17.62667Northing (m) :  6477340.653
    Project Grid - PCG94Perth Coastal Grid 1994
    Easting (m) :   50463.497
    Northing (m) :  276539.504
    Height Information
    Vertical datum :   AHD71
    Height (m) :         31.035
    RM3
    Geographical CoordinatesMGA94 Coordinates
    Horizontal datum : GDA94Zone :             50
    Latitude :     S 31 50 03.10749Easting (m) :   388486.218
    Longitude :  E 115 49 17.59808Northing (m) :  6477337.187
    Project Grid - PCG94Perth Coastal Grid 1994
    Easting (m) :   50462.745
    Northing (m) :  276536.045
    Height Information
    Vertical datum :   AHD71
    Height (m) :         30.927
    RM4
    Geographical CoordinatesMGA94 Coordinates
    Horizontal datum : GDA94Zone :             50
    Latitude :     S 31 50 03.03067Easting (m) :   388482.351
    Longitude :  E 115 49 17.45193Northing (m) :  6477339.511
    Project Grid - PCG94Perth Coastal Grid 1994
    Easting (m) :   50458.902
    Northing (m) :  276538.412
    Height Information
    Vertical datum :   
    Height (m) :         No height available
    Cadastral Connection Fieldbooks
    LG 110126
    LG 110953
    LG 132675
    LG 160816
    Special Notes
    Unknown Daterm1,bal60a,rm3 & bal49 are co-linear