Diver pUXO Survey & Positioning Award on EGL2
A long standing S4 client awarded Innovatum/ S4 an air diving pUXO (MTL) nearshore EGL2 west coast of UK survey & positioning support contract.
The cable route shallows from 3-7m water depths LAT provided for 24 pUXO/ pArch targets for investigation.
The client provided 27m Damen multicat was utilised with twin 20m spuds for static placement and positioning during diving operations and a 10’ survey container for the Innovatum/ S4 setup on 12hr operations.
During mobilisation the Survey PM and Mobilisation Engineer attended in addition to the Snr Surveyor who was to undertake the daily operations nearshore. All alongside checks and verifications were performed for the positioning systems as well as RTK position checks with a tertiary system against known port bollard positions for DGPS checks/ verifications.
The Surveyor supported the client marine and air dive teams throughout, in addition to our clients client as the EOD for TIR support and ALARP assessment/ provision.
The multicat was mobilised in East coast Scotland and then transit down to UK east coast for the scope of work an Innovatum owned survey & navigation/ positioning suite comprising, 2 x DGPS (Hemisphere VS1000 with RTK/ NTRIP differential and South Galaxy Wireless RTK with separate/ redundant NTRIP differential), Ixsea Octans Nano Gyro/ MRU, QINSy online survey & navigation suite with 2 x 6TB RAID/ NAS, full PC/IT & networking suite across a 19” rack mount with full backups, Helmsman and Diver Supervisor remote suite, 5G Router/ comms, Applied Acoustics Nexus 2 USBL system with Micro Beacons (diver bottle mounted with mitigated masking) (OTS pole mounted post our welding and NDT requirements support), plus a hired in spread comprising, OTS pole, Valeport SWiFT SVP and Valeport 106 current meter. Innovatum/ S4 also hired in a Digital Edge DVR suite to support our client’s diver visual inspection needs (as well as additional Aris camera requirements) and to satisfy the end clients requirements for higher spec DV delivery. Innovatum/ S4 setup an input string from survey to dive for the DVR and the video overlay requirements.
A single Snr. Surveyor undertook the daily operations and QC, and were supported throughout by the Survey PM and technical support engineer. The Surveyor was full involved in daily planning cross 6 (six) sites encapsulating the 24 pUXO/ pArch targets and for spudding in locations of the twin spuds and full TIR delivery in support of the EOD, as well as working the tides and the subsea currents in the very shallow waters (3-7m). Despite the extremely shallow water environment, the AAE Nexus 2 USBL performed excellently and only outages were when the diver turned their backs in error or during subsea dredging operations of the confirmed buried target due to high degree of suspended sediment and noise within the shallow water column.
A final factual navigation report was supplied to our client along with portable HDD copies of all diver DVR and Innovatum/ S4 positioning data sets.
The project was completed successfully after a 63-day program, with several targets requiring significant de-burial for investigation and removal.
