[Music] this is the indefatigable Lima platform it's the last remaining offshore rig in one of Britain's most productive gas fields paid up of two and a half thousand tons of steel and almost 15 miles of pipe work it's brought over a million cubic meters of gas up from deep below the sea for almost 40 years it's kept us warm supplying gas to 5 million homes we were the young Pioneers in those days we were the ones bringing oil and gas to the UK it was exciting this giant is about to be demolished it's going to be an immense engineering challenge [Music] Diamond coated wires will attack two-inch thick steel it allows the machines [Music] gas axes burning at three and a half thousand degrees Centigrade will bring it to its knees [Music] it's an emotional time for the men who put her up the North Sea Tigers that's 40 years of my life now gone taking her down will require remarkable technical skills and will provide a unique chance to see right inside this enormous installation okay did we get that hook reset please this is engineering Giants please Lima was at the heart of the indefatigable gas field which was discovered in the 1960s 70 miles off the Norfolk Coast now the gas has run out and it's being decommissioned the whole project will cost one and a half billion pounds and involve the expertise of more than a thousand Engineers removing every last trace of Lima will take nine months I'm Rob Bell I'm a mechanical engineer and I've always loved to get my hands on complex machines to discover how they work I'm Tom Wigglesworth I'm a trained electrical engineer with a passion for big machines foreign makes her last journey from the North Sea back to British soil we'll be taking you through every critical stage of the Engineering Process and as she's torn apart we'll uncover the secrets of how one of the world's biggest machines works Secrets as well as Austin Hand he worked on her construction at lower soft almost 40 years ago it started in Middlesbrough where it was it already slipped on schedule so shell decided to bring it from Middlesbrough down here to finish it off right right across here just on a barge motor against the key side yeah Austin's come to meet two other Lima veterans Bill Lindsay and mcneedham they haven't seen each other in over 20 years it's been a long time ah no you do I'd like to say we haven't changed I'm doing great really yeah probably the first time ever come across you was on Lima that's right you know who I am and you were the main man for me was quite it's quite special is that you you guys were the Pioneers really of North Sea gas and oil exploration and getting there getting the platforms out there it's exciting but it's a big learning curve as well for all of us we were on a young Lads I joined shell in 1971 as a 22 year old having worked in power stations and didn't even know what an off fuel platform looked like yeah six years or five years later and building them yeah in the MD is the Southern North Sea was quite a family unit we didn't have too many people coming in as Lake International and it was mainly local Lads and they're kind of all stuck together right and I think that's these days changed I mean it's always your friends and family you weren't necessarily working in around the gas and oil industry the stories you must have been coming home with every week there must have just been what so difficult for the families because if you're working in a shop or a factory they've got a perception of what it looks like but out there they had no idea what it was like you know I know my oldest girl was only about four then and I had to bring pictures home of a bed and a table with food on it and she was happy and she just thought I was working in the sea mcneedham's involvement with Lima started when she was built my relationship with Lima started in 1976 which entailed putting three new Platforms in and the first one was in De Lima more than 30 years later Mick finds himself back out in the North Sea working on Lima again at the very heart of the decommissioning process I got a phone call saying we need a company rep on board the uh heavily versus stanislav yudin taking up the Indie platforms would I be interested and I said two right over the challenge of working at Sea makes the complex decommissioning process more costly more difficult and more dangerous massive heavy lifting vessel the stanislav Udin weighing almost 25 000 tons has moored up against Lima mobile demolition yard costs half a million pounds to hire per day and will be home to the 120 Engineers who will harvest Lima from the sea their first major job is to plug the wells and sever the gas conductors the Lima platform had six Wells each tapping into a separate section of the gas Reservoir two miles under the sea the only way to board that deep is brace the well in sections as it's drilled each time a smaller pipe is passed down and the join sealed with concrete these are known as conductors now Lima's Wells have been plugged in four places with cement and the conductors are ready to be cut you end up with pipes within pipes within pipes so you've got concentric rings of pipes once the conductors have been cut you will actually see something that that's like a dartboard effect where you've got concentric circles within each other with concrete between them cutting through these materials would be a challenge on land but this surgery needs to be carried out 30 meters under the surface of a stormy North Sea Mateo mosca helped develop an ingenious cutting solution one of the many methods used in North Sea decommissioning so what have we got on there on this wire which is uh just a steel strand wire you guys embed the these Diamond bits these elements which are covered with the synthetic diamonds okay then the wire is constructed as an endless loop a continuous endless loop and it grinds its way through yes and gives a good finishing it doesn't alter the the physical structure of the metal locally it doesn't heat it so can we actually see this cut through yes that's what he's made for so let's go back out in the North Sea this process is happening 30 meters below the surface of the water these cameras help guide divers as they maneuver the Diamond Wire cutter into place [Music] the amount of friction created by the cutter can heat up the steel so much that it begins to warp so it has to be cooled by water saw working out on the Indie field has the cold North Sea to do the job but for this demonstration here on land cold water must be sprayed on to dissipate the Heat I mean the thing for me which really drives home this is quite a clever piece of kit but you've got thousands of tons compressing down and this cutter allows you to cut across that without it getting jammed a germ deep underwater would hold proceedings and cost tens of thousands of pounds to put right with this because it cuts all the way around that wire not just forwards but also above and beneath it it allows the machine to just keep cutting and slicing right the way through it's really impressive cut on Lima with the wells plugged and the conductor's cut they'll be able to move on to a bigger challenge removing the two and a half thousand ton platform this scrapping represents the end of an era the North Sea veterans who put Lima up know how tough it will be 34 years ago as a Young Man Austin Hand helped to bring it into the world now he's in charge of decommissioning on one of the north sea's biggest projects that's me and my boss gordonbox who was the guy who actually recruited me into shell I've been involved in that sense for 40 years either design and construct and initially my first sort of foreign to the offshore business was Indie Lima that's Lima in the background that's it it parked in the in the East Side in lower soft after we'd brought it down from Middlesbrough so that was us beginning to get it ready to go the platform has to withstand 15 meter high waves and Winds of up to a hundred miles an hour the legs or jacket is all important fixing Lima to the seabed removing it is going to be a mammoth task and will require as much engineering Ingenuity as went into building her so the jacket's basically a frame and and you place it on the seabed then you put piles in like pinning it and you drive the piles with a big hammer into the seabed that is a piling Hammer so it's about 60 feet high now above all these exciting things to do one of my jobs was to stand out all night with a clicker counting the number of blows of the piling Hammer you've got all the good jobs Lima's removal from the North Sea will involve taking away not just the jacket but the piles as well and before that happens I want to understand exactly how she was constructed and secured out at Sea I've got to show you how it works though okay all right so obviously on Lima this is done a hell of a lot further hours see how do they actually get it out they built this on land the jacket yeah they take it out on a massive barge though but the jacket it's basically only there as a guide for the piles and these are what takes the whole force of the top side so they go slot down into each of the legs so on Lima these piles were being driven 90 foot into the seabed must be a very noisy job it is a very noisy job that's why they do it so far out at Sea so they don't disturb anyone that is going nowhere with the legs firmly embedded the final part of the construction was to add the top side now 40 years on removing that top side is about to be the biggest test so far for Lima's decommissioning team weighing in at 1 350 tons this is the heart of the rig where the crew lived and worked processing the gas before piping it to shore of the legs will be an enormous challenge requiring knowledge skill and nerves of Steel the problem is how do you cut across the legs but still ensure the platform stays in place until craned off if for some reason we had a storm blow up and we just did a straight cut potentially the wind and the weather could vibrate the top size and start to move the top size if it's just on a flat surface it could start to move and potentially the last thing I want to do is have to go fishing to get the top size of the seabed lives could be at stake if they get it wrong and so a simple but ingenious solution is integrated into how they sever the legs cuts are shapes like Castle ramparts these cuts are absolutely genius and crucial to the whole decommissioning process having made the cut through the jacket the top side's resting on that what the castellations do gives the whole thing a lot more structural Integrity but when you do need it to be lifted the crane comes in and it's taken up genius the Final castellated Cuts are made to Lima's legs leaving her 1300 ton top side precariously balanced on top the worst thing that could happen at this stage is a storm the castellations could be brutally put to the test [Music] but the morning sun reveals that Lima's top side is still in place now it faces a new test this part of the operation is incredibly dangerous it uses a floating crane that can lift two and a half thousand tons that's as much as the Blackpool Tower ways which is why it costs almost half a million pounds to hire every day then in order to float more than two thousand tons of steel back to land a barge is needed this one is as big as a football pitch at this moment there's only one thought running through mixed mind is it going to be a level the entire lift is based on complex calculations which allow the crane to ballast itself against Lima's weight but these calculations are estimates so you're doing a theoretical model of uh not only the top sides weight but where the center of gravity of that top side is and they're about to find out how close to the truth they are the platform is successfully lifted off its legs for the first time in 30 years [Music] more than a thousand tons of steel are maneuvered with Precision safely onto the barge with stage one complete the engineers will turn their attention to the legs these are embedded deep into the Bedrock and must be cut off below the surface of the seabed the Tusk is tricky and will require an even more ingenious solution but as preparation for Lima to leave the indefatigable gas field continues I want to find out more about why she ended up there in the first place for geologist John Underhill gas and oil exploration is a lifetime's work I have this strange belief that Under the Sea when you go drilling through oil there exists pools of oil pockets of gas large you know sealed off sections that we drill and tap into and then it all comes releasing out is that true well there's a problem myth really that we we float on a reservoir of oil in reality it's Solid Rock with what's called poor space between it so air pockets that could be filled with gas or with oil these air pockets less than a millimeter in size fill it with gas over millions of years the paws make this kind of rock soft and easy to drill So Soft you can even feel it I'm moving grains of sand because they're coming apart and they're on my fingers so that's breaking apart that is a porous Rock the very same rock formation that makes up Lima's gas field off the Norfolk Coast travels the length of England and emerges on land here at time mouth in the Northeast it is a core from the southern or Sea from the Indie field can I hold this uh this precious thing up and from a sample like this once it goes into the hands of the geologist and it's tested for all its um components you can then say how how rich it is in oil or gas or we can calculate how much gas is in the Indie field for example from this and from the mapping of the seismic data geologists calculated that the Indie field contained 5.6 trillion cubic feet of gas enough to fill nearly 2 million Wembley stadiums under the right conditions gases formed from the remains of organic matter compressed under Brock for millions of years this layer is known as the Carboniferous layer or Source Rock Above This porous Rock holds the gas like water in a sponge in the gaps between its grains finally a layer of hard non-porous Rock known as the ceiling layer forms a cap locking in all the gas until someone drills a well there are two types of sore stroke one is oil prone and comes from either Marine sediments or lake sediments the other type is from Woody material coal that gives a gas prone sauce Rock so it's marine life that gives us oil and then land life that gives us gas primarily yes and here in The Cliff face below time with Priory we can see how the source Rock Lies Beneath the ceiling Lair identical to that found in the Indie field at the base we've got the the Carboniferous which is the The Source Rock level above that we have the reservoir unit the yellow Sands and above that right at the top of the cliff the recess at the top of the cliff is the ceiling unit which keeps the gas in the in the reservoir underneath the North Sea and all three are exposed here in this Cliff line out in the North Sea with Lima's 1300 tonne topside removed the next big challenge is to sever the 10-story high 1085 ton legs from the seabed all trace of Lehman must be removed to satisfy a so-called clean sea policy triggered by a dramatic event in the North Sea 17 years ago [Music] the bread Spa was a gigantic oil storage facility from which oil tankers transported the oil to shore by 1995 a pipeline had been installed so it was no longer needed shell had a plan to dump it by Towing it into the Atlantic and sinking it Greenpeace saw this as a potential environmental disaster so they sailed out and took control of the spa a protest that would make international news in a blaze of bad publicity shell reversed their decision and instead towed it to shore to be recycled on land and put the rest of the brentfield decommissioning on Ice Seventeen years later the process has restarted and asked in hand who began his offshore career building Lima is in charge did that kind of act as a precedence for now how all the fields and the platforms of decommissioned we thought it was a reasonable and logical thing to do to take it out to see two and a half miles down in the Atlantic and place it in this kind of Valley on the seabed we didn't do a very good job of explaining that so basically that resulted in the Oslo Paris convention of 1998 that said roughly speaking you put them there you take them away a clean Seas policy and that's what Greenpeace drove for and that's what they succeeded in getting there's so much involved in this that the cost of decommissioning just must be enormous Austin's estimate Austin's view 100 billion dollars of decommissioning in the UK there are those that would say I don't believe you Austin you've overstated it we'll see who's right in the end [Music] because of the clean seize policy out in the North Sea the Lemur Engineers now face a really difficult challenge cutting the legs of the jacket to remove it from the seabed in a way that leaves no Trace that it was ever there to achieve this the jacket legs must be cut off three meters below the seabed this means the only way to cut the legs is to sever them from the inside it's a job that demands a very special type of cutter as World expert George Jack explains there's no Blade no flame just water and grit is it the sea water that you're using there as you yeah we took a filter and sea water and through our pumps yeah pumping take up the high pressure and then introduce the abrasive to it as well yeah that's an actual gun that we introduced to the water well that's pretty hard stuff is it yeah yeah Garnet is a dark red silicon-based mineral although large crystals are used in jewelry some types possess strong Atomic bonds which make them very hard and ideal as industrial abrasives if you don't have that in your water it's it's not there's not enough friction to cut through the actual metal okay George is about to demonstrate to me the power of cutting with water and garnets this is a control room this is where we control the water pressure the great monitor okay so what pressure are here at the moment so now we're setting it just at 6000 PSI okay that's three to four hundred times greater than your typical water supply at home the abrasive on yeah put your introducing the grit into the system the pressure comes up [Music] there we go look at that I'll do it as soon as it starts coming through you'll see the water coming underneath oh no now you can see it's just gone through [Applause] so that's that's 50 millimeters of solid steel that's just 50 millimeters yeah so compared to say a high pressure jet hose that you might get for your washing your car or doing your patio from the hardware store yeah if you try to do that with this thing you'd probably do more damage than good right oh yeah it is the pressure we have barely read on one of these gauges the first Lane on that it's got me thousands foreign sure what kind of cut I'm expecting is it going to be a clean car is it going to be quite Jagged I don't know here we go that's clean that's a really strange things a bit the old Paul Daniels Debbie McGee he's gone right the way through all right so this is not for domestic use no not for diversity I'm afraid the limo Engineers are ready for the high pressure water cutter with the top side removed they're able to lower it down right inside the legs in theory if the severance isn't complete the crane could pull the stanislav Udin over in practice Fail-Safe mechanisms would Prevail but an incomplete Severance could still cost Millions we control it from a top side using our Hydraulics and everything okay and it'll cut do a 360 Degrees subsea just three meters below the seabed before they begin The Cutting every precaution must be taken the system is pressurized to six thousand pounds per square inch any Lead Core breach could be deadly an exclusion Zone around the cutter is strictly enforced because we've got high pressure hoses running across the deck if you put your hand up like that you're not gonna have anything left calculations estimate that the 360 degree cut of each leg should take 75 minutes all Mick can do now is time it and help once the other a lot of time has been given to each leg special slings are attached so all the slings uh it's they're not just something you get off the shelf or all these things are engineered and designed and built to the lens required now the crane must ballast itself against an unknown payload up to 300 tons of extra weight in marine life could have accumulated over four decades making the jacket 1400 tons as heavy as seven jumbo Jets all this makes the calculations for the stability of the crane more and more difficult puts the ballasting power of this stanislav udine yet further to the test and their stability in more Jeopardy and then the big tense moment for everybody because we are now going to start a little jacket but there's one thing we can't do we can't actually 100 guarantee they're cut by going to have a look at them hear the crane driver he starts taking the weight on the crane 1200 1400 tons somewhere in that region if he gets to 1400 turn and then he starts saying I'm at 14.50 now you're thinking I hope this is going to move shortly and your heart's probably going um and then also it just seems to go oh and it's a great saver and it's a great relief [Music] foreign Engineers work through the night to fasten Lima safely to the barge upon which she'll make her final Journey and that was it it was it was an end of an era for not only myself but for so many people that have worked on the in the fields throughout the last 40 years in the dead of night she leaves the Indie field behind forever and sets off on the 200-mile journey home to the Northeast mixed relationship with Lima has finally come to an end IA produce was so long brought lots of people work and more than that lots of great friends will happen memories I think those will stick I'm no joking hope I can't believe that excuse me but for Lima this marks the start of the next phase of deconstruction as Dawn breaks over the horizon Lima arrives at the mouth of the river tine from here she'll be taken to the famous Swan Hunter Shipyard for demolition it's amazing to think something like lima how important that was to us we just don't really consider that at all really it's delivering all that gas to our homes keeping us warm cooking our food well the Indie field actually produce enough gas in its lifetime to power the UK for a year and a half just in one gas field yeah at this one Hunter Shipyard they must wait for the tide to be just the right height so the barge is level with the key only then can the painstaking process of sliding over 2 000 tons of steel off the barge onto land begin four remotely controlled Bogies with a total of 56 axles each capable of supporting 36 tons of weight fantastic maneuver Lima into her final resting place now the next chapter in her story is about to begin Ivan Rayne is Geordie born and bred and is another person whose relationship with Lima and her sister platforms goes back to their Construction in the 1970s but you have to wear all this kind of stuff back in the 70s did you yeah we did but once you got offshore if you ever mentioned the word safety you're on the next helicopter home again he too has come a complete circle he's now here to oversee the Demolition and recycling of Lima all these pipes and valves and kind of meats everything we could sit around some dedicated to getting that gas up out of here the main function of this platform is to gather Gus from the seabed and the gas will be brought up through six pipes brought into this system here and then redirect it to another complex where it is collected and then it's sent to UK and Mainland for refining and then it gets redistributed throughout the UK and it comes into their house and that's what you use for cooking your roast beef on a Sunday is recycling team in charge of the demolition this is no ordinary takedown John so this has been out in the North Sea for 40 years where do you start in taking it all apart and recycling it the early deck will be cut off and pulled over and then we'll start this one with Section by section it's flattened they'll start cutting it up into very manageable pieces and the small other pieces the better the value they get for recitement for transport of the safe all right so now we're talking money typically you know what are we looking at for recycling this whole platform it could be looking anything from 180 to 200 000 pounds wow scrub value after 40 years of service providing gas to millions of people and jobs and even a home to hundreds of North Sea Tigers Lima is finally about to be brought to her knees first her infrastructure is weakened by strategic cuts next it's time for the excavators to really get to work steel wires are attached to the heli deck and the machines go into reverse this red accommodation module is next for demolition its fixings to Lima's frame have been severed and the excavators are standing by [Music] Mick Cubit spent four years living and working on Lima as an electrical engineer it's almost 19 years to the day since he last saw her most incredible it's like a bomb performance hit the place in fact it's bordering on unrecognizable I don't want to pull any more emotional punches on you make but I think that is your old bedroom that red tin Shack over there I am afraid to have spent several in effect the equivalent to two years worth so as someone four years half on half off that's right yes some 700 nights spent in that little tin box so we're about to walk into your accommodation block mate this is a home sweet home home sweet home looks fairly devastating to me it's been really had the insides ripped out of it so this was the living area then Mick was it this is where you passed the time well prior to um the introduction of satellite television we used to show films that were hiding by the company got your own little block buffer yeah so this must have been pretty cramped how many people lived in here this was accommodation for eight people two two lots of bunks um the shower for all four was in here as the shower tray with a wash basin place just here arm shower wash basin and that was it that was your emergency exit so I'm like it's the middle of the night you're sleeping you're comfortable Abode and there's an emergency alarm the worst case scenario what what what's the order of service three offs the three off's been block off where you would Block in all the well stop the gas coming onto the platform you would then vent off what's the third off you just off follow me okay quickly Mick it's an emergency situation for Mitch Lima colleagues we're United in lowestoft for the first time in over 20 years all that's left are photos and shared memories of their incredible offshore lives how many times would you have been offshore at that stage directly probably not many yeah we used to fish than me Tony sure there is some entertainment to be had made our own entertainment what was Food Supplies like I mean did you eat well it fairly well but you would have a choice of a fillet steak a bit of fish I said decent spread that isn't it Christmas crackers exclusive devices offshore if you had a good Chef you had a good platform and you had a productive platform that's one thing I really take away from this whole process is it isn't just the hardware it isn't just all the steel and everything that's it's the family of all the people who've built it worked on it how does it feel now that that that particular field and and Lima platform's not there anymore is it does it kind of sit with you does it rest with you or when you're finished you think you know that's 40 years of my life yeah you know now now gone you just realized how old you're but again back at the swan Hunter Shipyard another relic of the Glory Days of the North Sea has been uncovered a start reminder of just how treacherous it can be so this looks like a Horror Story Mick but I believe it was just a heli deck when they removed it it smashed into the front there but this is your survival raft isn't it yes this was the broker capsule as it was known on the platform awful thing to steer be in circular and an awful thing to ride in we do the captain I have been done the coxson's training on here and I've been to see with guys who are happily throwing up and it is not the best place to be even with a dozen guys in when you've got a couple of them thrown up into their hard hat I'm hoping that years of training means that my Lima veterans have grown stronger stomachs because I'm about to get my first taste of the Brooker pod experience and this is exactly the kind of one you had up on Lima is it absolutely yes identical identical well luxurious was it no that's how we became friends [Laughter] pods like these have safely evacuated more than 2 000 people in over 60 incidents around the world since Lima was built been given the job of releasing the capsule and it's fair to say that the speed of the response takes me by surprise they were designed for the Gulf of Mexico but the bobbing donut was no match for the waves and currents of an undulating North Sea the survival pods still vital for an industry which has claimed hundreds of lives and now usually boat shaped I'm being shown the ropes by Nick goldsmic who's been teaching North Sea Tigers how to navigate these pods since 1989. I mean we're moving around like a baby still this this round shape seems like a very odd design for a boat to me yeah it's partly to do with strength and it's partly to do with ease of operation the traditional style of Lifeboat has got a cable at the front and the back okay and there's a chance that that can hang up there is no chance and no possibility to that with this shape of bow obviously there is a compromise to the shape and that is that they do Bob around like a cork round boat how do you even steer this thing yeah well that that is more difficult than a traditional lipochet but the advantage of that is they're very maneuverable but she's steered basically from the tiller here which again is unusual in a Lifeboat to steer a boat from the front if you were to evacuate how long would you be able to survive in a craft like this a fairly long world would be the answer to that I mean there's enough water and food for a week I would not want to be stuck in here for a week with 27 other people you get to know them fairly well you were to become quite an intimate an intimate team [Music] thank you so how was that Jen spring back a few few memories yeah after you say 20 years on I never thought I'd be back in one of them back on tyneside there's nothing ship-shaped about Lima which has been slowly cut down girder by Gerda making it no longer possible to trace the pathway that gas would have taken snaking through miles of Lima's pipework from under the sea to our kitchen Hobs so to solve the mystery of how she worked I'm going to see an offshore platform in action and Trace the fossil fuel route it's never been on a helicopter before thanks to gas and oil Aberdeen heliport is Europe's busiest ferrying almost half a million passengers offshore every year across the North Sea more than a hundred lives have been lost since air transfers began which is why every possible safety technique is used in the event of the helicopter ditching this suit will increase my survival time in the freezing North Sea from just minutes to about seven hours but I hope I don't have to put it to the test after an hour of seeing nothing but c a platform comes into view [Music] okay a hundred miles offshore from Aberdeen in the northern North Sea this is Nelson which produces both gas and oil the fossil fuels pathway on Nelson is very similar to Lima's gas pathway so I'm going to track the route from under the sea to our homes and explore how current technology works Alima had six Wells Nelson Has drilled 28. Nelson's manager Nick McLeod is going to show me the drill floor okay wow wow see it could go down his cars 20 000 feet 20 000 feet and eventually we get down to What's called the payzone which is here yeah the peso that's where the money is yeah that's where the oil and gas is okay what happens if everyone cheers in the old days hopefully not these days the first crucial stage for the fuel that emerges is the Well Bay [Music] everything's moving about is juggling it's really noisy absolutely unbelievable it's unbelievable to consider that they've made this side of machines it's even more incredible when you realize that we're 100 production engineer Murdo McDonald is here to explain the first step of the fossil fuels pathway oh which involves something known in the trade as a Christmas tree call the Christmas hanging off if you've got quite an imagination yeah he's got quite a bit after a two weeks off shot yeah when a Well's drilled the raw fuel comes up the conductors into the Well Bay on Lima this was gas on Nelson it's gas and oil here the Christmas trees large Assemblies of valves and gauges help control the flow of oil and gas entering the platform I'm ready for my first offshore job oh whoa two three four five turns what have I done the clothes are choking five percent which has restricted the oil flow coming up from absolutely stage two of the pathway is all about separating what emerges from the well into its constituent Parts like a science fiction film when a well is drilled oil comes up the conductors into the Well Bay but it's not pure oil it's a mixture of oil gas and water in order to extract the valuable oil and collect the gas the whole mixture is sent to one of the most important devices on the platform the separator model of Nelson separator to explain to Rob how it works it's bafflingly simple we have here a bucket switch to the Casual Observer appears to be generic Grand Cola mixed with vegetable oil which is actually exactly the same as oil water and gas right that's what's coming up from the Bottom of the Sea so we've got a pump but normally that's got enough pressure to be forcing itself up exactly that would be pushed up under its own steam yeah so what you do you separate them out the gas will naturally flow off to the top yep lighter than both of them so that can only be tapped in offensive processed yet water is heavier than oil so this weight is very important because the oil floats on the water okay you see that easily here so the brown stuff is the water and the creamy stuff is your oil exactly so because the oil is floating underwater it flows over the top of this we're creating this secondary chamber here which is pretty much all oil so coming out of here you get pure oil coming out of the bottom of this section you get flat Cola or water yeah coming out the top this separation stage of the fossil fuels pathway is vitally important because it tells the Energy company how much gas and oil they're producing to do this every day each well is taken out of production and diverted into the test separator you too how's it going in the control room Pete O'Connor is monitoring the results so that's the production valve there the diverter valve which is open that's the test one which is shut so by putting it into the test separator it lets us know how the well is performing how much oil it's producing how much water how much gas it's producing all our wells now are starting to water out all over 80 percent water that didn't used to be the case no no they all gradually they gradually decline in oil production so the test separator is actually uh testing the the mix of oil to gas to water for each individual well yeah we have a spot rate there which at the moment can tell you we're doing 19 357 Barrels near enough today at the moment wow at that rate Nelson produces oil worth around one and a half million pounds a day not a bad return the third and final stage of the fossil fuels pathway is exporting it [Music] butter is cleaned and pumped overboard oil is cleaned and then pumped down the export pipeline to shore but it's not all over for the gas some is exported to gas terminals excess is burnt off on the iconic Flair stack but most of it is diverted to something known as the gas lift to do an important job because of the weight of the ocean on this trapped reservoir of hydrocarbons yeah it's all under pressure it's kind of like this so the moment the drill pierces it wow you've got it it all comes out now obviously quite soon it loses pressure so once they've been tapping the oil off so it becomes like the feel becomes flat yes exactly it becomes flat it becomes devoid of pressure yeah so what you do instead of pumping it up yeah you push gas down into the reservoir which makes the oil light because it's got gas in it which then sends it back up you basically make the world's biggest Soda Stream yeah the gas Clash collected from the separator is compressed repressurized and then re-injected back down the well via the Christmas tree forcing more precious oil up the force required to do this is huge on the platform Murdo shows me where they get it from it's a gas compressor which is essentially a jet engine and it's one of the noisiest things I've ever experienced gas compressor takes the pressure from five Watts instructions that's 147 times atmospheric pressure [Applause] [Applause] but while Nelson's conductors are still full of naughty gas Lima's conductors now lie severed from the rest of the platform on the key side at the swan Hunter yard near Newcastle and demolishing them is going to be a feat in itself because of the way the wells are drilled and constructed they end up with pipes within pipes within pipes all sealed with thick layers of cement turning this into small pieces of scrap metal requires a process known as bombing first the gas ax is used to cut along both sides of the long steel conductor then to get at the inner pipes the excavator steps in once it's made short work of the concrete the inner steel pipes are revealed and the process starts all over again with over a third of a kilometer of conductors to scrap it's a lengthy process foreign on the other side of the yard only Lima's legs or jackets as it's known still remain built from over a thousand tons of high-grade steel it must be broken up into small chunks to be recycled the first stage is to bring the structure to its knees strategic Cuts must be made so the legs collapse neatly but it's a dangerous job as soon as a cut is made the platform is weakened and may fall at any time so are you guys responsible for yes we are yeah yeah I would like to be the the guide of the Final Cut who's in charge of that whoever wants to do it the backside gets a bit Twitchy when the uh puts in the final I mean I think it was me at the moment the ax is finished I'd be turning and running do you actually there's no need to run in a carefully controlled and calculated procedure tow lines attached to the top of the jacket will be used to pull it over this is the first time this method has been attempted anywhere in the world we attached two ropes either side of the jacket and a safety rope to the very back of the jacket just to stop the bite legs toppling the wrong way foreign the engineers have put down a bed of Earth for the legs to collapse onto to cushion the impact got two lines haven't they um yeah two pulling range these guys will take the tension up on nowhere just give it a little tug it's quite exciting just the anticipation of it before it's going to come down everything clear don't let anything in now because we're about ready if the 30 meter high back legs were to fall in the wrong direction they could land on a factory behind the shipyard still excited to see these come down brilliant [Music] [Music] foreign the demolition of this jacket for recycling is the final act in the scrapping of the Lima platform although veteran Lima engineer engineering he has not seen Lima the platform he cut his teeth on for 20 years well there she is now wow I'm so used to building things so to see it dismantled and in pieces it's just so you're probably quite used to it in this condition in a second I can still see the module yeah just on the different yeah a curve of its life yeah now that really reminds me of going on and off that barge for months yeah to get to get it completed just walking over a gangplank and working 12 14 hour days every day but it was fun and exciting so yeah that gives me a bit of a buzz you know we with the young Pioneers in those days we were the ones bringing oil and gas to the UK it was exciting good memories so I've seen Austin as this process has unfolded I've seen the huge machine of Lima been reduced to small piles of Steel rubble and I was surprised to see so much Timber on the show can you tell me a bit about this well I used to say in my day that the rigs were made of wood and the men were made of steel but that's not actually true so what this was we covered the main steel deck with this Timber so that when you were lifting stuff off Supply boats and Landing it on the platform you had some absorption material that avoided sort of damaging the deck or or even the container so all this timber here was was to provide you with a huge cushioned area to protect the whole thing like a massive chopping board anyway absolutely yeah this steel tubing once formed the jacket that supported the top side now been broken up into sections ready to be recycled [Music] but to the expert eye even these fragments reveal the challenges of these early pioneering designs in the 70s sometimes the quality wasn't great so this is a good example here now this is a very tough angle for a welder to get in at these points you get right down in there exactly so you know in an ideal world that brace would have been at a less of an angle but very often the designers just wanted it to be structurally robust okay and then when it arrived for us to deal with it in the construction yard and think wow why did they do that yes and so on on paper mathematically it makes perfect sense exactly but sometimes it wasn't constructable but again this was a learning process that would feed that back in to the next jacket and say can we do this slightly differently and and that's how we evolved the industry getting better and better uh and making it easier to be sure these Wells were sound and solid all these things had to be considered even with a relatively simple structure like a jacket for the final time the excavators pull on Lima's infrastructure to bring down her last story all the leg is going to go there she goes [Music] it's very very sad to see that something that you built when you were a 25 year old you're pulling it to bits when you're a 59 year old and it just shows your time moves on and nothing stands there Lima is now unrecognizable just heaps of rubble and thousands of tons of scrap steel amazingly some 99 of this will be recycled the wood from the decks is poked and made into paper even the 300 tons of algae that collected on the legs will be recycled for compost but most lucrative is the steel once the various grades have been separated out it's then smelted and made into new girders and pipes fittingly just half a mile down the road steel from the smelted remains of machines like lima are being used to build this a brand new 21st century platform a few hundred tons this weighs in at a whopping 12 000 tons [Music] platforms like this are giving the North Sea a new lease of life [Music] foreign [Music] but Lima and its gas field are now just a memory [Music] removing it costs more than 200 million pounds took two years and over a million staff hours to recycle 2 000 tons of steel 311 tons of algae find homes for two generators and scrap two toilets and 12 well-worn bunks [Music] pioneered offshore platform installation and now involved in the biggest new North Sea industry taking them back down again [Music] [Music] [Music] [Applause] [Music]