Per the British Antarctic Survey press release:
“A team of scientists and engineers has for the first time successfully drilled over two kilometres through the ice sheet in West Antarctica using hot water. This research will help understand how the region will respond to a warming climate.
The 11-person team has been working on the Rutford Ice Stream for the last 12 weeks in freezing temperatures at low as minus 30 degrees Celsius. On Tuesday 8 January, following a 63 hour continuous round-the-clock drilling operation, the team broke through to the sediment 2152 metres below the surface.”