The world’s largest boring machine was lifted out of an underground tunnel in Seattle, where it has been stuck for more than a year after it broke down mid-job. The gigantic drill, known as Bertha, stopped working in December 2013 after digging just 1,000ft of its two-mile journey to replace the aging Alaska Way, which was damaged in 2001 by an earthquake. A crew from Dutch construction company Mammoet used a huge red crane on Monday to hoist the front end of the machine – which is fivestories tall and weighs 2,000 tonnes – out of the ground so it could be repaired. Scroll down for video . The front end of gigantic digger Bertha is being lifted out of the ground by a huge red crane in a painstaking process . The machine, pictured in the ground, stopped working after digging just 1,000ft of its two mile trip to replace an aging waterfront highway . Workmen spent hours on Monday carefully lifting the equipment, which weighs 2,000 ton, to the ground so it can be fixed . A release by the Washington State Department of Transportation said removing the removing the equipment, buried 120 feet underground, would take workmen at least 16 hours but there was no set schedule, adding: ‘Crews will take as long as necessary to prepare for and safely complete the lift.’ The operation was the fourth and final lift in the department’s repair programme, with crews already removing three pieces of Bertha’s exterior from the pit, the department added. The machine's breakdown and other construction issues have left the $80million project two years behind schedule and sparked concern about cost overruns and other unforeseen obstacles. The original highway overhaul was expected to cost $2 billion and be completed by 2015. The new timeline for replacing the busy Alaskan Way Viaduct, damaged in a 2001 earthquake, is 2017. A white crane arrives on the scene in Seattle to help lift part of Bertha, which had been buried 120 feet underground . Workers prepare a gravel pad as Bertha is pulled out of the ground. Mammoet, the company who set up the huge red crane to remove Bertha, has completed similar lifts across the world including hoisting a Russian nuclear submarine from out of the Arctic Ocean . Matt Preedy, deputy Highway 99 tunnel administrator for the Washington State Department of Transportation, praised the work of Mammoet, Seattle Tunnel Partners (STP) and tunnel-machine maker Hitachi in a report to The Seattle Times, saying they had devised a good lifting plan and did an 'excellent job'. The mammoth task saw the digger gradually heaved to ground level at a rate of four to five inches a minute,  with the help of seven miles of cable. He added that Bertha now needs to be disassembled, inspected and repaired before construction companies commit to a time frame where the machine will start work again - with some contractors saying work could start again in August, . Mammoet has performed other lifts around the world, including recovering a Russian nuclear submarine from the bottom of the Barents Sea, in the Arctic Ocean. There had been concern that Bertha, buried 120 feet might not be able to move itself to the pit opening because it had experienced various mechanical issues, including increased temperatures, before it stalled. The huge section of the digger was pulled up four to five inches a minute, using seven miles of cable, according to The Seattle TImes . Workmen scale the top of the red crane, to ensure the ropes are fixed properly as they lift the machinery out of the ground, while Seattle Tunnel Partners project director Chris Dixon walks along the site to check the rescue operation is going to plan . This photo was shared on Twitter by @BerthaDigsSR99, with the caption: 'I'm up and on the move! Being carried towards the white repair platform.' Twitter account @BerthaDigsSR99 also shared this picture with its 15,000 followers of the part left in the tunnel. The caption, posted at 5.44am GMT, read: 'A look at the section of me that will remain in the pit. Catch you in the morning.' But, using its own power, it was able bore through nearly 20 feet of concrete last month to break through a wall leading to the rescue pit's opening, ready for it to be extracted this week. Thousands of people have followed Bertha’s journey back to the ground on a dedicated Twitter page, called @BerthaDigsSR99. Along with mechanical issues, the project has been set back by other concerns. In February, four men at the site were injured when a rebar wall collapsed, causing them to fall 25 feet. Two Seattle firefighters walked about a half mile into the State Route 99 tunnel and carried out one of the injured men while the others walked out. A fifth worker escaped injury, while his four colleagues were taken to Harborview Medical Center,  One of the men suffered a fractured arm. Bertha , which weighs around 2,000 tons, was able bore through nearly 20 feet of concrete last month to break through a wall leading to the rescue pit's opening . The machine's breakdown and other construction issues have left the highway project in Seattle two years behind schedule and sparked concern about cost overruns and other unforeseen obstacles . The original highway overhaul was expected to cost $2 billion and be completed by 2015. The new timeline for replacing the busy Alaskan Way Viaduct, damaged in a 2001 earthquake, is 2017 . The back end of Bertha, the five-story high drilling machine which has become stuck underneath the city of Seattle . Crews struggled for weeks to reach the object that was blocking the boring machine, from moving forward 60 feet below the surface after it got stuck .
Gigantic device, known as Bertha, stopped working in December 2013 after digging just 1,000ft of a highway tunnel . Workmen used a huge red crane to pull the front end of the broken-down tunnel in painstaking operation . Crane was lifted to ground level at a rate of four inches a minute and using seven miles of cable . Breakdown has meant the $80 million project to replace the Alaska Way has been delayed by two years .