MCU25 0087 - Reference Document - Coastal Hazard Assessment (As Published)

                      SandMap – Report of Survey for Sunshine Beach Profiles



                                          RTK post processing
                                 The Septentrio Altus NR3 RTK GNSS unit utilised for both the beach fieldwork and as a
                                 positioning system for the CEE ECHO single beam remained in RTK fixed mode at all times
                                 throughout the survey. Alerts were set up to warn of any dropout situation however this did
                                 not occur during this survey. No post processing of GNSS data was required.

                                          Required precision
                                 A total horizontal uncertainty of plus or minus 0.5m at a 95% confidence level was determined
                                 for this project. Horizontal accuracy checks to established survey control as detailed below
                                 proved the NR3 GNSS system was well within this specification during the project. Overlap
                                 was achieved between land based RTK GNSS data and sonar soundings and all vertical
                                 differences were less than 0.1m while horizontally the profiles met within 0.5m.

                                          Rejection criteria for position data
                                 Filters were used to ensure minimum satellite count was 6 and a satellite elevation mask of
                                 15° was set. During the project the satellite count was rarely below 20, due to the system using
                                 4 constellations. This ensured a maximum HDOP of 4 and maximum VDOP of 2 was easily met.
                                 The maximum age of corrections was 3 seconds.

                                 Horizontal control
                                 For this project, a Smartnet Australia GNSS solution was utilised for the survey using the base
                                 station located at Noosa. The Regulation 13 certificate for this base station can be found in
                                 Appendix B.
                                 Initial checks carried out using an Altus NR3 quad constellation RTK GNSS unit against local
                                 marks PSM 18419 and PSM 108353 with low horizontal uncertainties, produced good results
                                 confirming suitable accuracy of the SmartNet base station solution for use over the survey
                                 area.
                                 The check results can be found in Appendix A: Survey Control Checks.

                                 Vertical datums
                                          Marine datum
                                       All reported depths are referenced to Australian Height Datum (AHD).

                                 Connection to vertical control
                                 For this project, a Smartnet Australia GNSS solution was utilised for the survey using the base
                                 station located at Noosa. The Regulation 13 certificate for this base station can be found at
                                 Appendix B.
                                 Initial checks carried out using an Altus NR3 quad constellation RTK GNSS unit against local
                                 marks PSM 18419 and PSM 108353 with low vertical uncertainties, produced good results


                      Rev. no.    Doc No.                                          Version Date          Doc Approver
                        1         P0100-20251020                                   20/10/2025            Rod Tansley                        Page 8 of 20

                                              The controlled version of this document is registered. All other versions are uncontrolled.
Document Set ID: 24631530
Version: 1, Version Date: 24/03/2026