UXO Surveys

Unexploded bombs, mines, torpedoes and shells, deposited as a result of conflicts, maritime disasters and established firing practice areas are known as Unexploded Ordnance (UXO). Because they can be located on or near proposed marine renewable development sites, unexploded ordnance can pose a real threat to both your staff and your operations.

Gardline provides unexploded ordinance (UXO) surveys and related advice to a range of clients on a global basis. 

With our expert knowledge and experience, we usually work in partnership with UXO consultants to identify potential unexploded risks. Our UXO survey package is industry proven for delivering exceptional quailty data. It is easily deployed from our coastal survey vessels and can be tailor to meet your UXO survey specification. 

During and after completion of survey operations, we will map the hazardous sites and work with the UXO consultant to facilitate the generation of clearance certificates for specific locations. 

Our vessels are ideally suited to both shallow and deeper water offshore windfrm sites. Supported by Gardline's established technical, QHSE and logistical services, our fleet is available 24/7 and has capacity for any scale of project. Our commitment to our clients, coupled with our high-quality data has ensured that we reamin a leading choice for the offshore industry. 

UXO Survey Equipment:

  • Towed array of up to 4 Geometrics G882 marine magnetometers with calibrated altimeters and depth sensors. 
  • Remote wich control system and terrain following aids.
  • Edgetech FS4200 500/600khz Side Scan Sonar
  • Kongsberg high resolution multibeam echosounder. 
  • Shallow sub bottom profiler: Hull mounted/shallow towed multi-element 3-7khz pinger. 
  • High accuracy DGPS surface navigation.
  • Applied Acoustics Easytrak Nexus USBL positioning to simultaneously track all five towed sensors. 
  • Gardline Voyager5 navigation control, quality control and survey planning.
  • Gardline Geofusion geophysical processing and interpretation software.
  • Oasis Montaj 'UX-Detect' software for anomaly mapping.


  • 24/7 operational capability
  • Low magnetic signature vessels.
  • Variable magnetometer separation up to 15m swath
  • Towfish altitude of 2m or greater.
  • Water depth range limit 70m
  • Magnetometer system upgrade rate 10hz, detection sensitivity 1nT.
  • Sonar resolution 20cm at appropriate setting.
  • Deployment and monitoring of multiple sensors (MBES, SSS, SBP and magnetometers) enables corroboration of object detection whilst on the survey vessel.
  • Preliminary analysis of data during survey onboard the vessel for coverage/QC.
  • Onshore final processing - presentation as charts and GIS layers.

For more information on our UXO Services, please download our brochure here. 

UXO Services