Drone that drags cables and small shaped charges for controlled detonations in place. Mudcover is removed with waterjets. Scanning is sonar and magnetic field mapping. Strange new things are reported, otherwise automated finding, attaching of ropes via sprayonglue after cleaning.
Prize seems rather low. I imagine a waterproof robotic dog with a huge snorkel, a magnetometer, and a big grapple to hoist (not drag) munitions to shore. Different sizes for aircraft bombs and grenades (from a picture in the article -- I wouldn't have thought of that case).
SFR 50K would be a rounding error in developing that.
Ressources used: electricity, ropes, glue, detonation capsules.