An anonymous reader writes: A Russian company is building a massive natural gas pipeline that will run across the Baltic Sea floor. But first, they must clear the150,000 unexploded bombs sitting at the bottom of the sea, left there by the Russian and German armies in the 1940s. Clearing them all will constitute the biggest commercial mine-clearance project ever. About 70 of these mines, each filled with 300 kg of explosive charge, sit in the pipeline’s path, mostly in its northern section just south of Finland. And so the company is bringing in robots to do the dirty work. Here’s how it will work: A research ship deploys the robot to the seabed, where it identifies the exact location of the explosive. After sounding a warning to surrounding ship traffic, scaring fish away using a small explosive, and then emitting a “seal screamer” of high intensity noises designed to make the area around the blast quite uncomfortable for marine mammals, Bactec’s engineers erupt a 5 kg blast, forcing the mine to detonate. This process ensures the safety of humans plus any animals living in the surrounding environment. The operation concludes with the robot being redeployed to clear up the scrap of the now-destroyed bomb.