North Sea Blowouts and Fires 1964-2020

North Sea Blowouts and Fires 1964-2020

Once aboard offshore installations, the usual myriad of dangers are ever present, including collisions between vessels and fixed structures, moving machinery, crushing hazards, high voltage, high pressure, dropped/shifting loads, slips, trips and falls on the drill floor and pipe and work decks are ever-present. However, these are not the only dangers offshore. Fires and occasionally the immense forces of Mother Earth’s high-pressurised underground oil and gas reservoirs have dire consequences in the form of blowouts when uncontrolled crude oil, condensates and gas leaks have arisen. Numerous instances have occurred globally, and the North Sea basin has experienced its fair share since oil and gas exploration commenced in the mid-1960s.

Blowouts result from uncontrolled releases of gas, condensate, oil, water and solids at high to extremely high pressures. The sudden high-pressure releases can occur with incredible velocities, and enormous amounts of liquids, solids and gas ejected are at a high temperature. Hence, the risks of explosion, fire, and widespread pollution are all present. Blowouts can represent a potential loss of life, terrible environmental devastation, equipment loss and loss of gas and oil energy revenue. Blowouts can occur when drilling into a shallow gas pocket or an unexpectedly high geological pressure zone. They can arise from geological strata fractures, human error, equipment failure, or external causes such as collisions and fires. The possibility of a blowout exists at all drilling stages (whether production or exploration) and during maintenance and inspection of drilling and production equipment. Five to six blowouts occurred annually between 1970 and 1977 in the Gulf of Mexico alone. Between 1992 and 2006, five thousand six hundred and seventy-one wells were sunk in the federal waters of the US Outer Continental Shelf; thirty-nine blowouts occurred, or one blowout per every three hundred and eighty-seven wells drilled.

An offshore platform, as designed, constructed, towed, located, and operated, is subject to uncertain environmental forces, such as heavy storms, hurricane-force winds with mountainous waves, deep waters, shifts in the seabed, and high-pressure collapsible geological structures. These forces can cause the drilling platform to sink, collapse, corrode, and blow off location, thus generating blowouts via the sheared wells. In addition, ships can collide with a platform in conditions of reduced visibility or because of poor seamanship, engine, propulsion or dynamic positioning failures or failures in radar and communication.

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On 22 June 1964 (Non-Fatal)

A gas blowout occurred in the German Sector of the North Sea. The twelve-legged jack-up barge, Mr. Louie, was transferred from the GOM to the North Sea during the summer of 1963 and had been actively drilling Well B-1 since 23 May 1964 in thirty-four-meter water on the German Bight, twenty-seven nautical miles north of Juist Island, thirty nautical miles west of Helgoland Island.

This borehole was the first exploration well in the German Sector of the North Sea. The casing had been run and set to a depth of one thousand one hundred and forty meters. Upon the bore-strings drill bit puncturing into a gas pocket of very high-pressured carbon dioxide at twenty-nine hundred meters below the seabed, the borehole became over-pressured and was closed by blowout preventer rams. The released pressurised gas thereafter escaped deep in the borehole, deviating sideways and migrating along fault lines at an angle upwards to the seafloor, erupting four hundred metres northeast of the platform. There are no eyewitness accounts of the initiation of the blowout. Still, the crew on the jack-up observed a gas and sediment gushing flow that elevated the water surface the following day.

The jack-up was then moved off-site for safety reasons, and specialised companies tried to kill the blowout by pumping heavy drilling mud into the borehole. It was stated that the released gas mainly consisted of carbon dioxide; However, contemporary newspaper reports and internal reports noted that the released gas was nitrogen, which is typical for many reservoirs in the North German Basin.

Attempts to stop the uncontrolled gas release were unsuccessful, but gas emissions ceased over the following weeks, and the borehole drill site was abandoned. The blowout created a thirty-one-metre-deep seabed crater that measured five hundred and fifty metres in diameter at seabed level, sloping down to four hundred metres width at the bottom. The focused gas discharge at the seafloor removed up to five million tonnes of sediments in the following weeks of vigorous venting. The cavity has been named Figge-Maar.

On 30 June 1964 (Fatal)

Just eight days after the B-1 well blowout in the German sector, the C.P. Baker drilling barge owned by Reading & Bates Offshore Drilling Co., a Catamaran design of three thousand eight hundred and thirty-one gross tonnes, measuring close to eighty metres in length and thirty-eight point five metres in width, suffered a high-pressure shallow gas pocket blowout while drilling in Block 273 Eugene Island area Gulf of Mexico, at two hundred and eighty-four metres depth from the rotary table, in a water depth of fifty-seven metres. Forty-three persons were onboard the barge. MV Delta Service was moored alongside the C.P. Baker, and MV, Mr. Jake, was moored alongside the MV Delta Service. It started with a blowout at 03:00 in the morning. Gas and water erupted like a massive geyser over and around the barge, then rapidly developed into a raging explosive fire inferno that encapsulated the entire barge and shortly thereafter caused the barge to sink. In that disaster, twenty-one barge crew died, and twenty-two were injured with varying degrees of burn and other injuries. In addition, one marine crew member of MV Delta Service died from burns, and another was severely injured. A deckhand on MV Delta Service released MV Mr. Jake’s mooring lines, enabling her to escape; MV Delta Service followed shortly thereafter; both boats were surrounded by fire when they moved away, the fatality onboard MV Delta Service was releasing the ropes when a massive explosion occurred, he was engulfed in flames emitted like a blowtorch from a side door of the C.P. Baker and later died in the vessel’s hospital. Before the two ships had rescued the last survivor, found floating in the water, estimated to be between fifteen and forty-five minutes, the C.P. Baker had sunk. Gas continued to erupt and burn for thirteen hours. And some gas was emitted for a further twenty-four hours. On 01 July 1964, divers located the capsized C.P. Baker on the seabed and commenced the recovery of bodies; three craters were also found varying in size between one and six metres in diameter and up to three meters deep. At the time, this was the worst oil and gas accident to have occurred in the GOM.

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On 15 November 1968 (Fatal)

The Hewett Alpha 52/5A offshore platform situated sixteen nautical miles off Cromer Head, Great Yarmouth, UK sector, North Sea suffered a blowout. At around 09:00, while pulling the string out of the hole, a potent gas and crude kick that evolved into a full-blown blowout erupted via the open end of the drill pipe string on the drill floor. The BOP annulus rams were activated and squeezed around the drill pipe, reducing the leakage. Blessedly, the gas did not ignite. There were gale-force winds and high seas from the southeast at the time of the incident. The standby vessel MV Hector Gannet, with a gross tonnage of three hundred and sixty-one with a crew of eight men, came to the rescue. The forty men on the platform draped a fifteen-metre-long landing net over the platform’s west side and climbed partially down, awaiting the standby vessel. When the stern of the standby vessel was brought under the landing net, a wave lifted it and slammed the hull brutally down onto the platform’s westerly boat landing, breaking off a girder section. Still, the Captain heroically managed to maintain position, enabling eleven men from the platform to drop onto the back deck from the net. The vessel was again slammed down hard against the rugged steel boat landing, and further damage arose. This second impact opened a gaping hole in the vessel’s aft side below the waterline. Two men hanging on the net saw a colleague drop with such force to the boat deck that he broke his leg and had to be dragged from the aft deck. They both froze in fear with vice-like grips to the net and had to be hoisted by ropes back up to the platform’s railing by men from the drilling team. The crews experienced the most terrible time, caught between the cold water tempest and the danger of being burnt alive. During this mission, the MV Hector Gannet moved away, listing heavily, then rapidly capsized over on her side at 09:36. The converted Lowestoft trawler MV Boston Hornet, a standby vessel from an adjacent field two nautical miles distant, then arrived on sight and rescued sixteen of the Hewett Alpha’s and MV Hector Gannet’s survivors who had managed to clamber onto the capsized vessel’s hull. Three of MV Hector Gannet’s eight crew members died, and the five survivors of the vessel crew suffered minor injuries. Most of the remaining twenty-nine men on the platform had no alternative but to jump into the raging sea and enter deployed life rafts. The M/V Hector Gannet sank at 09:53. A Whirlwind XK 969, a British European Airways (BEA) Helicopter, a Bristows helicopter and RAF helicopters were involved in the rescue, finally retrieving the toolpusher and the radio operator while hovering beside the helideck buffered by the turbulent gale force winds. Needless to reiterate, the crews experienced a most terrible time. Miraculously, not a single man of the platform’s crew was life-threateningly injured.

The MV Hector Gannet accident was the first loss of an auxiliary vessel in the oil industry in the North Sea. Paul “Red” Adair was involved in capping the well. Adair, along with the Huwitt platform’s toolpusher Vernon and radio operator Robert Orrell, were the first three to jump off a helicopter hovering over the platform’s helideck. Some days later, the blowout was stopped using rubber balls pumped down the annulus with mud.

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On 22 April 1977 (Non-Fatal)

The first uncontrolled severe blowout in the Norwegian sector of the North Sea occurred on the Ekofisk 2/4 Bravo platform, an integrated jacket steel platform with production, processing and drilling capacity. The field operator was Phillips Petroleum Company Norway. The accident occurred during maintenance work on an oil production well designated B-14, when three thousand meters of production tubing was pulled during a workover operation. For this type of workover, safety valve blocks (Xmas tree) on the production deck must be removed before the tubing is pulled, and a particular arrangement of safety valves, denoted blowout preventer (BOP), must be installed. The well is open from when the Xmas tree has been removed until the surface BOP has been established. During this critical stage, provisional means of assuring it will not flow uncontrolled must be used. Before the Xmas tree is removed, the well is killed with mud, a fluid of sufficiently high density to generate enough pressure at formation depth to prevent oil and gas from rising out of the reservoir up the tubing and casing strings. The Ekofisk 2/4 Bravo blowout occurred during the installation of the surface BOP.

Before the Xmas tree was removed, a mechanical safety device, a Down-Hole-Safety-Valve (DHSV), had been installed inside the production tubing at approximately thirty-three metres below the sea floor to prevent flow from the well. After the blowout was stopped, this valve was found practically undamaged on one of the decks of the platform. It had forcibly been blown out of the tubing.

The immediate cause of the blowout was that the DHSV had not been properly locked into the seating recess in the tubing at the time of installation during the late evening of 21 April, thereby failing to prevent fluid flow when the well became unstable during the morning of 22 April. Despite this, the accident was not unavoidable. Two warnings of abnormal ominous conditions were observed earlier. However, appropriate, prudent actions were not then taken. The first warning came when the mud was seen flowing from the DHSV’s control line. The second came when the Christmas tree had been removed, and mud came up through the tubing. Each of these warnings should have resulted in the immediate cessation of the work and shutting down the well.

Earlier that same day, a general emergency lifeboat drill was held, a blessing as everyone on board learned the procedure. Within fifteen minutes of the kick, one hundred and twelve crew members on the platform were efficiently and rapidly evacuated. One hundred and ten crew members evacuated via the platform’s lifeboats; two men climbed down rope ladders and jumped into the sea and were recovered from the water by an inflatable boat from the diving support vessel DSV Seaway Falcon, which was active alongside the platform assisting in deluging/drenching with her water cannons.

Asger ‘Boots’ Hansen, Richard Hatteberg and Paul ‘Red’ Adair, along with several hard-working Norwegian roughnecks with sledgehammers and nerves of steel, were involved in the kill operation and the dual pontoon eight-column Santa Fe DLB Choctaw I (the first semi-submersible pipe laying barge) was used as the operational base.

The gas and crude blowout lasted for eight days until 30 April 1977. The crude oil spill was initially estimated at twenty thousand tonnes but later reduced to nine thousand tonnes. Given nobody was injured or killed and that the blowout did not cause a catastrophic environmental disaster, one could say that the Bravo Blowout could be characterised as a valuable but expensive experience that objectively, over time, saved lives. By 1977, a total of twelve hundred wells had been sunk in the entire North Sea basin; five known blowouts had occurred, but none until then had happened in the Norwegian sector. More stringent regulations evolved that were enforced by dedicated governmental oversight institutions over the following decade.

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Achievements, trials and tribulations of MODU Sedco 135 design semi-submersible drilling rigs.

On 03 June 1979 (Non-Fatal)

The Ixtox blowout occurred while drilling in the Gulf of Mexico with the MODU Sedco 135-F, a first-generation offshore drilling rig with a basic geometry involving a unique equilateral multi-braced triangular-shaped three-column nine-anchor semi-submersible owned by Southeastern Commonwealth Drilling Company, Calgary, AB. The rig was a Sedco 135 type designed by naval architects Friede & Goldman. It had been constructed in 1966/1967 at Victoria Machinery Depot Co. Ltd., Canada. The MODU was the seventh of eight rigs utilising the Sedco 135 design. The MODU Sedco 135, the first of the type, had been built by Ingalls Shipyard of Pascagoula, Mississippi, USA, in 1964/1965. In the spring of 1977, Pemex, the National Oil Co. of Mexico, awarded a long-term offshore drilling contract to a Mexican drilling company, Perforaciones Marinas De Golfo, S.A (Permargo). In August of 1977, Sedco Inc. and Permargo S.A. entered into a bare-boat charter agreement. In November 1978, the rig started drilling the Ixtox 1 well, an exploratory borehole in the Bay of Campeche, Gulf of Mexico, fifty-four nautical miles northwest of Ciudad del Carmen, Campeche, off the Yucatan peninsula, in a water depth of fifty metres.

By 01 June 1979, the bore string bit had reached three thousand five hundred and ninety-six metres when mud return was lost. After a hold and adding further mud, drilling continued to a depth of three thousand six hundred and fifteen metres below the seabed when drill mud circulation was lost for the second time on 02 June, resulting in a loss of hydrostatic pressure. Pemex, the client, against the advice of the onboard Sedco superintendent and tool pusher, decided to pull the drill string, then run the drill pipe back in open-ended and pump heavy fibre-rich mud down to seal off fractures.

After a ten-hour hold, tripping commenced but was paused every three hundred metres to verify the stability of the mud and pump in additional mud to replace the extracted drill pipe volume. The high reservoir pressure led to a kick on 03 June while the pipe string with heavy wall drill collars was positioned through the seabed blowout preventer (BOP). As the roughnecks unscrewed a drill pipe joint on the drill floor, the borehole kicked, cross-threading the two drill pipes and jammed the pipe tongs, rendering the roughnecks incapable of raising or lowering the remaining eighty or ninety meters of string into the hole.

Usually, an uncontrolled return flow can be shut-in by activating the BOP shear rams. These rams are designed to sever and seal off the well on the ocean floor; however, the BOP shear rams could not sever the drill collars’ thick steel walls. The BOP Hydrill rams were activated to squeeze an annulus rubber sleeve ball around the drill collar; however, the blowout continued through the drill collars and drill pipe’s internal bore, which led to a catastrophic blowout. The ejected mud was followed by a large quantity of oil and gas at an increasing flow rate.

Fifteen minutes after the kick, the oil and gas fumes exploded after contact with the rig’s live mud pumps, starting a fire. All sixty-four rig crew evacuated, and there was no loss of life, albeit some crew members suffered minor injuries.

Some three hours later, the derrick, close to a hundred triple stands of drill pipe, the suspended riser tower, universal, ball and slip joint, and much of the equipment stored on the rig’s drill floor collapsed and fell in a mangled mess onto and around the blowout preventer down below, causing further damage to the BOP stack on the seafloor.

Nine hours after the kick, orders were issued to cut the rig’s anchor chains, with the inferno raging, a challenging, complex task that took twenty-four hours to complete with anchor handling tugs dragging the anchors and anchor chain legs. The damaged rig was first pulled three hundred meters from the inferno, thereafter towed twenty-six nautical miles northwest of the site and boarded by eleven marine surveyors.

After several weeks of inspections, MODU Sedco 135-F was declared a total loss, towed a further ninety-four nautical miles easterly to deeper waters, and scuttled on 12 July. Historically, the MODU was the first semi-submersible to complete a world tour by travelling from Victoria, where she was constructed, to New Zealand, the North Sea, and Brazil, finally ending her days in Mexican waters.

The blowout resulted in the largest recorded single oil spill in North American history, with an estimated three point three million barrels of crude oil spilt into the sea. It remains the Western hemisphere’s second-largest oil spill, only surpassed by the Gulf of Mexico Macondo MODU Deepwater Horizon oil spill that erupted on 20 April 2010.

On 15 August 1979 (Fatal), During the intense work to cap and shut-in the Ixtox I well, the blowout claimed its first human life: Allan Anderson, a thirty-two-year-old American national with two young children. Working as a saturation diver for Taylor Diving and Salvage Co., he died during attempts to shut-in the well while saturation diving from the lay barge LB Meaders. Allan had locked out from the bell and, with an extended umbilical length, had reached the tipped-angled-over BOP at the wellhead. He inadvertently got caught in the escaping gas vortex and blown to the surface. The well was finally capped on 23 March 1980.

The third of the eight Sedco 135 designs built (a sister rig of MODU Sedco 135-F), the three-column, nine-anchor, multi-braced triangular-shaped semi-submersible MODU Sedco 135-B (Bruyard), owned by Southeastern Drilling Company, Inc, was delivered in 1965 by Mitsubishi Heavy Industries, Japan. On 01 December 1965, the rig suffered a catastrophic fatal disaster while on her first tow from the Hiroshima Yard, Japan, to Brunei, Northwest Borneo.. The Dutch-registered tugboat AHT Willem Barendsz, with a bollard pull of forty-two tonnes, was towing the rig when it suddenly broke into three pieces due to weather and other inexplicable causes. Thirteen of the fourteen men onboard the rig during the tow died in this tragedy; four of the deceased were Dutch nationals, employees of the Dutch tugboat company N.V. Bureau Wijsmuller. The nine others were employees of the South Eastern Drilling Company and of the Shell group. Miraculously, a single survivor, dehydrated and floating on a wooden pallet, was found days later by a passing Japanese trawler. The bottle shape of the columns with the tapered top section was intended to reduce the influence of sea conditions when the rig was on the bottom. These early semi-submersibles sometimes operated in shallow water and sat on the seafloor. However, this column type reduced the rig’s dynamic stability when buoyant and floating. The Sedco 135-B tragedy resulted in stricter stability requirements by the American Bureau of Shipping.

On 06 August 1969 (Non-Fatal), The MODU Sedco 135-G, the eighth and final Sedco 135 design-build, was constructed by Mitsubishi Heavy Industries 1968/1969 and delivered in 1969. The Atlantic Richfield Company were the drilling operator when the rig suffered a blowout and raging fire while on location at the Petrel 1 Well, Petrel field, Bonaparte Gulf, off the coast of the Northwestern territories, in the Timor Sea, Australia, after drilling an 8 3/8-inch hole to three thousand nine hundred and seventy-eight metres depth into a high-pressure gas pocket, a pressure build-up occurred, and the crew lost control of the well. The BOP rubber annulus preventor unit was closed, but the rubber seal failed, and due to the kick, the driller lost control of the draw works. The blocks dropped onto the rotary table, significantly complicating the situation. The initial influx volume was substantial, around eight times the average well influx in similar cases. Both pipe rams were sealed; as the drill pipe was moving, they also failed. The crew strived to add heavy mud and then cement into the well for several hours.

Gas continued flowing, and the anchor winches were activated to pull the rig away from the well, but the marine riser would not release. Evacuation then started. The gas caught fire around the rotary table and then spread to the crew quarters and control room, causing extensive fire damage to the rig. The rig was successfully winched off location, and the riser stack parted at the subsea BOP. The gas then unhindered rose in a plume beside the rig. The rig fires were subsequently extinguished. There were no fatalities or injuries. The gas plume from the seabed was purposely lit to ensure vessels would not inadvertently sail into the danger. It would burn continuously for nearly ten months until the relief well was drilled. The damaged rig was towed to Singapore and refurbished. On 31 January 1970, three months after the blowout, the repaired rig had been towed back to the well site to attempt drilling a relief well.

Much practical and valuable knowledge was gained from this blowout. Know-how that resulted in reinforced BOP equipment, higher-pressure rated BOPs, dual BOP rubber annulus preventor units, adequate-sized shear rams along with other improvements that would hinder reoccurrences, and instructions to avoid moving the drill pipe when attempting to kill a well. These lessons were incorporated globally by the industry to impede single-point failures.

On 01 February 1970 (Fatal), a tragedy occurred during the anchor handling operations performed eight hundred metres southeast of the burning Petrel 1 well site by the anchor handling tug AHT Sedco Helen, measuring sixty-one meters in length and twelve-point-two metres in width. The AHT Sedco Helen, with a crew of twenty men, was positioning mooring buoys for the MODU Sedco 135-G in marginal weather conditions when, inadvertently, her propeller fouled a buoy cable. The steel buoy punctured the ship’s hull, flooding the engine room and causing it to sink in minutes to the sloping seabed at depths between eighty-two and ninety-seven metres; nine lives were lost. Eleven men, most of those on shift, were saved.

A large-scale search was conducted using RAN patrol boat HMAS Assail, RAAF Neptune aircraft A89-281, tugs Rode Zee and Super Tide and the oil rig supply boat Cookshore. The bulk ore carrier Musgrave Ranger, outbound from Darwin, Australia, en route to Japan, also turned back to join the search. The tug Rode Zee picked up the eleven survivors. Salvage divers used a diving bell (famously used in the RMS Niagara gold salvage during World War II and reconditioned for the work) to assess the possibility of salvaging the AHT Sedco Helen, but it was considered too dangerous.

The Petrel 1 relief well was spudded on 07 February 1970 and concluded in May 1970.

In 1966, the MODU Sea Quest (renamed Sedco 135-C in 1977), the fourth Sedco 135 design rig, was delivered by Harland and Wolff Shipyard, Belfast, Northern Ireland; she discovered the UK’s first North Sea oil on 14 September 1969 in the Arbroath Field. On 07 October 1970, MODU Sea Quest drilled a well ninety-five nautical miles east-northeast of Aberdeen that led to the discovery of the Forties Field, the north sea, the UK sector’s first commercially viable giant oil field, the first discovery of oil in commercial quantities in the UK Sector of the North Sea.

On 17 January 1980, MODU Sedco 135-C experienced a blowout while drilling the Funiwa-5 well for Texaco Overseas Petroleum Company of Nigeria (TOPCON) offshore Warri, Niger Delta, Nigeria. Between two and five hundred thousand barrels of crude oil were spilt; the environmental disaster is deemed by experts as amongst Nigeria’s worst cases of marine pollution. The blowout occurred during completion operations.

The blowout continued until 30 January 1980, when finally, the oil caught fire. Consequently, the well bridged and the flow of oil ceased. It is worth noting that before the fire outbreak, the flow continued unabated for twelve days and understandably caused massive marine pollution. Attempts were made by an internationally recognised oil well blowout control specialist – Red Adair Corporation, to combat the spill. The Corporation was enlisted to cap the overflowing oil well. Due to the hazardous nature of the blowout, the effort to restrain the well was too dangerous and was aborted. In the face of failure to cap the well, two additional drilling rigs, the MODU Kermac-Transworld 46 and the MODU Sedneth 1, were brought to the scene to drill relief wells. This effort could not achieve much as the well bridged before the relief drilling could reach the blowout interval. Admittedly, the MODU Sedco 135-C completely caught fire, thus ending efforts aimed at salvaging the well. The fire damage was such that the platform was subsequently scuttled in deep waters. It is claimed that one hundred and eighty civilians died from the MODU Sedco 135-C oil spill due to direct and indirect effects of pollution in the Nigerian Delta.

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On 06 October 1985 (Fatal)

The six-column dual pontoon MODU West Vanguard suffered a gas blowout while drilling a wildcat exploratory well 6407/6-2 at Haltenbanken in the Norwegian Sector of the North Sea. Smedvig Drilling owned the semi-submersible drilling rig on hire to Statoil. The rig reached the location on the evening of 03 October but was slightly delayed due to the wreckage of a crashed aeroplane on the seabed at a depth of two hundred and twenty-one metres, which demanded the eight-point mooring spread to be adjusted.

The well had been spudded on 04 October, and the wellhead and thirty-inch conductor casing were subsequently set. The top section of a well is usually drilled without a blowout preventer (BOP). Any gas encountered that returned with the mud should be guided away to the leeward of the rig by a diverter valve system on the cellar deck below the drill floor. The drilling had progressed well until the drill bit rather unexpectedly encountered a shallow gas-bearing sandstone formation two hundred and sixty-three metres below the sea floor (five hundred and six meters below the rig’s drill floor rotary table Kelly drive bushing). Heavier drill mud was circulated; at this stage, neither the twenty-inch casing had run and set in the thirty-inch conductor head nor had the subsea BOP landed on the subsea wellhead.

After drilling recommenced, gas measurements in the return mud increased again, drilling was paused for the second time, and more heavy mud circulated. Drilling was then continued upon the drill bit reaching five hundred and twenty-four meters below the Kelly Drive bushing. Approximately two hours after the gas return was first discovered, the pressure increased drastically. The shale/mud return to the shaker room was closed as the percentage of gas in the mud return increased, and the A-line side of the rig’s gas diverter system was activated to lead the gas and solids overboard on the rig’s downwind side. The B-line side remained closed. More heavy mud was pumped down into the well through the drill string. The diverter system, which had been tested days earlier, proved unable to withstand the abrasive pressurised mix of mud, solid cuttings, gas and sand. This abrasive blend wore through the pipework elbows and flowed onto the platform. The offshore installation manager/tool pusher (OIM) ordered everyone to the lifeboats. The order to shut-in the well and disconnect the wellhead connection was given just before the escaping gas ignited, causing the first powerful explosion twenty minutes after the gas flow was routed into the diverter systems pipework.

The evacuation took place with lifeboats. The accident was the first of its kind in the Norwegian sector. A mushroom of flame was observed around the derrick. Fires broke out immediately, and subsequent explosions were registered. Immediately after the first blast, the OIM activated the release mechanism for the rig’s two stern anchors, enabling the bow anchors to pull the rig off the well and away from the expected blowout gas plume that would be coming up through the water column. The lifeboat evacuation was conducted without significant challenges, and personnel in the two lifeboats were aboard the standby vessel M/V Black Ice within ninety minutes.

On the other hand, the evacuation was particularly dramatic for the tool pusher and the stability manager, who climbed down a support column stairwell and swam away in their survival suits before being rescued by the crew of an FRC from M/V Black Ice. Eighty people were on board; seventy-nine were saved. One Norwegian roughneck who was on the drill floor was never found.

The sea continued to boil with gas, which was partly aflame. The rig had been dragged away by the weight of the two bow anchor chains from the centre of the blowout gas flow that erupted on the sea floor and started expanding immensely. A cubic metre of gas at the wellhead increased its volume on its journey through the water column as the water pressure decreased; upon reaching the sea surface, each cubic metre had expanded to twenty-three-point-one cubic meters. Although the amount of gas escaping declined considerably within a week, a substantial flow could still be seen on the sea surface six months later. Material damage was massive and amounted to several hundred million Norwegian kroner. However, the rig was operational again by June 1986, when it discovered oil in the same area. The accident was the first of its kind in the Norwegian sector.

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On  10 November 1992 (Non-fatal)

At 09:39, the alarm sounded in the central control room on Frigg, Norwegian sector. A fire had erupted in one of the TCP2 platform shafts. Non-essential personnel were immediately ordered to evacuate the platform, and seventy people crossed the bridges to the QP platform via the TP1 platform. The blaze began during welding work thirty metres down in concrete shaft number five, one of the platforms three shafts, where a new riser for gas and condensate from Lille-Frigg was to be installed. The same shaft accommodated the gas and condensate risers from East Frigg, North-East Frigg and Odin fields, plus an umbilical with hydraulic oil and methanol lines to East Frigg. Methanol leaks from the flexible umbilical had been observed several times, with minor fires breaking out no less than three times during October. The relevant faults had rapidly been repaired each time. The flexible control umbilical contained ten stainless steel tubes: five designated for methanol, four for hydraulic oil and one spare. These tubes were used to transport pressurised methanol (anti-freeze) and hydraulic oil for injection into East Frigg’s subsea satellite control modules. The leaks had arisen because small methanol molecules driven by high pressure had penetrated through the small bore tube walls and accumulated inside the densely packed umbilical’s outer sheath. Pressure had then forced this methanol back up to TCP2, where it leaked out in the connection box where the umbilical head was clamped to a riser leading up to the topside. Extensive safety measures were instituted because welding to install the Lille-Frigg riser was to be carried out close to this precariously leaking connection box. A screen of steel plates was initially installed as a barrier between the welding area and the methanol drain tank and control panel. Fire-retardant mats were then laid to cover any cracks between the floor and the lower part of the steel screen. A tarpaulin was hung between the connection box and the welding area, while the floor was also covered with foam to prevent fires. Despite these extensive safety measures, the tarpaulin caught fire. Methanol had leaked from the connections between the umbilical and the manifold and out into the box. Since methanol is heavier than air, it had accumulated under the tarpaulin and been ignited by welding sparks. The fireguard on duty at the site first spotted a flame between the tarpaulin and the connection box. He attempted to extinguish the fire with foam. Simultaneously, further bluish flames emerged from the rear of the box. Efforts were also made to put these out with foam. By then, welding had ceased. Flames four to five metres high suddenly sprang up, and the tarp began to melt and burn. Another fireguard in the immediate area arrived, the alarm was sounded, and the shaft was evacuated. The fire was now out of control. In an attempt to douse the flames, large volumes of water and foam were poured over the site from the platform topsides, thirty metres up above. This distance proved too great for effective fire-fighting. The water curbed but did not extinguish the flames. Thick clouds of smoke made it difficult for the smoke divers to reach the site of the fire and pinpoint its exact location. However, this was accomplished by the second smoke diving team to go down the shaft. The flames were reduced as the pressurised water was directed at the source. However, as soon as the water dousing was paused, the fire flared up again. A third smoke diving team managed to remove the shielding plates and tarpaulin with the aid of a boat hook on a long pole, and water was then sprayed directly at the source. On this attempt, after ninety minutes had elapsed, the flames were permanently extinguished. A further hour and a half was needed to ensure the blaze did not reignite. It was then established that nobody was injured. A rescue helicopter crew from the 330 squadron at Stavanger’s Sola airport had nevertheless been scrambled in case complications arose. In addition, southern Norway’s joint rescue coordination centre had notified all vessels and helicopters in the area to be on standby. Elf, the field operator, had its emergency response helicopter ready, and the AHTS Normand Skipper, a standby vessel, constantly sprayed water on the outside of concrete shaft number five, striving to cool it down. Gas production from the whole Frigg field had immediately been shut down when the alarm sounded.

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On 28 November 2004 (Non-fatal)

An uncontrolled situation occurred on the Snorre A four-column tension leg platform (TLP), a massive integrated production, drilling and quarters (PDQ) unit with a displacement of one hundred and four thousand nine hundred tonnes, held in place by sixteen steel tension legs, located in blocks 34/4 and 34/7, one hundred and eight nautical miles west of Florø in the Tampen area of the Norwegian sector of the North Sea during work on Well 34/7-P-31A.

The work consisted of pulling a production tubing pipe string out of the existing well, drilled in 1994/1995, in preparation for boring a deviating sidetrack well. During the day, the situation developed into an uncontrolled gas blowout on the seabed, releasing uncontained gas on and under the facility.

Two hundred and sixteen persons were on board; one hundred and seventeen personnel not involved in work to remedy the situation were initially evacuated by helicopter to nearby facilities. Seventy-five persons remained on board, after which forty additional crew were evacuated. The remaining thirty-five persons were involved in the work to shut off the gas release/leakage, and they stayed on board until the incident was under control.

The work to regain control over the well was complicated by the gas bubbling up under the facility, which prevented vessels from approaching to unload additional drilling mud. The MPSV Normand Mjølne launched her work class ROV, but as their sub only had six hundred meters of tether, it could not reach the wellhead template while the ship remained in the stand-off position due to the potential gas atmosphere. The MPSV Normand Mjølne and the PSV Ocean Knarr remained on standby with additional engine power online with their fire pumps running in case their high-pressure, high-volume fire-fighting water cannon capabilities were required.

After mixing mud from the available well fluid control chemicals, this heavy mud emulsion was pumped into the well on 29 November 2004, stabilising the well.

Based on its potential, the Norwegian Petroleum Safety Authority (PSA) characterised this incident as one of the most serious to occur on the Norwegian continental shelf. The situation developed when a part of the production tubing, called a scab liner, was pulled up through the subsea BOP. A suction effect caused gas to enter the wellbore, and from the wellbore, rising gas found its way through a purposely punctured hole in the production tubing 2 7/8 inch tailpipe per the engineered program and a damaged area in the downhole 9 5/8 inch casing. The gas leaked through the ruptured casing wall, bypassing the BOP, and erupted from the seafloor, creating several craters close to the northwest tension leg suction anchors and the massive subsea multiwell template frame.

Several different gas alarms sounded, which was first thought to be a problem with gas leaking from one of the process modules into the cooling water; then, other gas alarms went off in different places, and the crew struggled to find the source of the gas leak. About two hours after the first alarm, gas was observed in the sea below the platform. The situation had become quite dramatic; substantial amounts of gas bubbled below the platform and entered the fall pipe, providing coolant to the platform machinery and fire deluge systems.

Another serious concern was that the flare tower tip pilot gas flame could not be extinguished. The main power generators were shut down, and the emergency power system did not provide enough power to operate the mud pumps needed to mix heavy mud to counter the gas in the wellbore. After most personnel had been evacuated, the skeleton crew remaining on board frantically improvised an operation to pump heavy mud into the well. During the night, this operation slowly succeeded, and by the morning of 30 November, with all the stores of mud chemicals depleted, they managed to stabilise the well.

I was involved in the aftermath of this incident while aboard the MPSV Far Saga sub-sea intervention vessel as a shift supervisor in late December 2003 and early January 2004, having been urgently summoned from a short time off in Thailand to provide remedial subsea assistance if required. This was when seabed disturbance, pockmarks and deep tunnel blowhole craters had arisen from the subterranean gas blowout. The most prominent hole was eight by three metres in diameter and presumably reached the casing leakage site over a thousand meters below the seabed. Aggravation was found on the seabed surrounding sections of the northwest corner’s sizable triple cone-shaped concrete suction foundation anchor points where four of the floating tension leg platform’s sixteen steel tethers were anchored. Each of the four corners has three interlinked suction anchors that measure seventeen meters in diameter and are embedded twelve to thirteen meters into the clay-based seabed.

Further areas of concern were found on the west side of the massive two thousand-four hundred tonnes (in air), forty-four slot wellhead template system (forty-two slots were in use) measuring forty-eight metres in length, thirty-two metres in width, and (including the three-metre skirts) nineteen metres in height situated on the seabed at three hundred and seven meters water under the TLP. There were no injuries.

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Worldwide, there were one hundred and eighty-six reported Loss Of Well Control (LOWC) incidents and three hundred and sixty fatalities associated with those LOWCs between 1980 and 1999

Worldwide, between 2000 and 2015, there were one hundred and fifty-six reported LOWC incidents and seventy-four fatalities were associated with those LOWCs

Three hundred and fourteen reported blowouts/well releases have occurred in the waters of the US Gulf of Mexico Outer Continental Shelf and the Norwegian and UK sectors of the North Sea from 01 January 1980 through 31 December 2020. Of these LOWC incidents, ninety-four occurred in the UK and Norwegian sectors of the North Sea.

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With these ever-present dangers, I learned to always, upon arriving onboard a rig/platform or ship, immediately check the evacuation routes, lifeboat, life raft, survival suit, and life jacket locations and memorise the alarm signals posted on the bulwarks. In addition, I would familiarise myself with the types of watertight doors, fire and blast-proof doors and associated passageway airlocks. The alarm signals are not generally standardised and, to a degree, vary in detail between individual vessels, platforms, and rigs. Your bunk number, accommodation deck level, cabin number, and position determine your muster station. The last thing you wanted was to end up trapped in a dead end or barely floating in the cold water in a thin overall, or worst case, naked or wearing only underpants. In addition, meeting up at the wrong muster point during muster drills is embarrassing and aggravates colleagues, some of whom have been loudly awoken by alarms from a deep sleep and cannot leave the muster points until all hands are accounted for. In my instance, I was dispatched to numerous installations and vessels that substantially differed in size, layout, and configuration. If one’s rotations are not spent permanently on a specific installation or vessel, all these details can be challenging to memorise.

There was, at times, an unspoken feeling of concern amongst the Norwegians that perhaps the management of the international companies operating off Norway’s southwest and west coastline was far more concerned with oil extraction than safety. There appeared to be a gung-ho disregard for danger at times.

The North Sea became a magnet for colourful characters. At times, it was a theatre of the absurd. During late 1986 and early 1987, the most horrible of toolpushers I ever met was an American on the MODU Polar Pioneer. He was an old-fashioned, crude redneck who disliked all Norwegians; looking down on the local Norwegians, he called them ‘coon-ass noggies’ (it’s unnecessary to elaborate from where the word derives), consistently treating them poorly, as he did with everybody else.

The man claimed to speak ‘Merican’ and insisted anyone who didn’t was an idiot. Perhaps the man used a foreign tongue because it wasn’t a language with which I or any other Norwegian schooled person was even remotely familiar. Maybe that was where the animosity originated: meeting a Norwegian who could speak better English. Perhaps I shouldn’t have communicated in complete sentences or used more than one-syllable words; instead, I should have just grunted like a chained baboon. Anyway, it was too late now. We didn’t like each other.

PETAS had been contracted to provide the required, obligatory downhole tooling inspection services to the rig, but not wanting to pay the total price, the American had insisted on only one inspector for what was supposed to be a two-person job. The redneck seemed to get sadistic satisfaction from imposing this burden on me, which demanded I pull more than sixteen to eighteen-hour shifts daily.

A deck-mess (canteen) provided shelter, where shivering or soaked workers spent short breaks and could get a hot cup of coffee or tea and a bun. This arguable necessity angered the redneck, and whenever he saw the crew having a break, he would leave his warm, comfortable office and follow them. Then he would stand in front of their Formica table, with his index finger extended, hovering over his wristwatch, and he would move it in small jumps, one degree at a time, like it was the second hand and loudly say, “Tick-tock, tick-tock,”. He would do this until the workers left the canteen and returned to the windy decks or inside to the noisy weather-sheltered work and pipe floors. The Norwegian crew disliked the man intensely, bordering upon hatred. His attitude to people and management methods were in strict contrast with the traditional, more civilised Norwegian ways. Eventually, out of disgust, I stopped taking the two or three short breaks in the cafeteria over the sixteen hours I worked daily.

A confrontation was inevitable. The man was bad-mannered, less educated and had enough mental health issues to keep a convention of Californian psychologists busy for years. I disliked him intensely. Trouble soon showed up in the form of a large hook. A Norwegian crane operator approached me and said he was concerned about the condition of the twenty-five-ton SWL (safe working load) whip-line hook that hung from the starboard main deck crane. I told him it wasn’t on my provided inspection punch list, but the man insisted it was a safety issue and that a preliminary inspection should be done. The whip line was used to hoist heavy loads from supply vessels and shift equipment around the deck areas. A crane hook with a suspended load that failed could cause horrendous injuries, deaths and terrible damage.

The hook’s paint and primer covering were removed where not worn away, and the entire surface area was cleaned for inspection; MPI (Magnetic Particle Inspection) and CVI (close visual inspection) were performed. I made sketches of the deep radiating surface, subsurface cracks, and other severe damage found on the hook’s load-bearing surfaces. Armed with the report, the crane operator went to the toolpusher’s office to request a replacement hook or, at least, a complete repair. This misstep was the first of nine mistakes I recall making throughout my offshore career. Albeit this one, I would have repeated, as it was the right thing to do, but if a similar situation had occurred later, I would have gone to the toolpusher before starting the inspection.

When the crane driver entered the redneck’s office, he looked out of his window and saw the crane sitting idle. When confronted with my report, the toolpusher had apparently turned bright crimson and blown a gasket and began shouting, “goddamn coon-ass noogies with their clipboards were trying to sabotage his motherfucking oil rig as he did not have a spare whip line hook.” In retrospect, I should have gone to the toolpusher’s office and informed him before inspecting the hook. Albeit today, the opposite would be the case. An inspector would be severely reprimanded, if not immediately fired, if he did not flag a safety issue and stop the usage of the damaged equipment.

Seething hatred was percolating and mutual, but I had learnt a lesson. The world’s ways are not always logical. After two weeks of brutally relentless hard work, I felt I had performed far and above what was required. Having singlehandedly managed to do a two-person job in the allocated time and prepared all the documents, I received praise from both day and night shifts of the rig’s drilling and roustabout teams. After boarding the helicopter, I felt relieved and worn out upon returning to the mainland.

However, not long after that job, a complaint arrived at the PETAS office in the form of an official notification, in writing, from the company that operated the oil platform. The toolpusher had sent a report to his head office with several fabricated grievances against the young Norwegian inspector from PETAS.

Initially, I was shocked by the report. I could not comprehend how anyone could have been dissatisfied and categorically stated that mistaken identity was the culprit. I had worked relentlessly and exceptionally diligently, seldom taking a break, and had received praise and gratitude from the rig’s crew. Then I recalled the hook incident, and it dawned on me who the culprit was. I was furious and decided the next time I met that pathetic redneck, I would provide him with something real about which to complain. Meanwhile, the obnoxious American was sitting in his warm office on the platform, thinking he had won, but that was because he did not know he had just kicked a hornet’s nest. Eventually, there would be a reckoning.

Later, I was choppered to the Oseberg A platform for an inspection job. Discovered in 1979 by Norwegian Hydro, the Oseberg Field consisted of two enormous, interconnected platforms with Oseberg A on four massive concrete legs fixed to a base resting on the seabed and Oseberg B positioned beside it on a steel jacket. Some years later, in 1999, Oseberg D, also placed on a steel jacket, would be set and interconnected to A with a walkway.

I preferred going to the fixed-production platforms, as the comfort and quality of accommodation were much better than on smaller mobile drilling rigs; the downside was the unbelievable amount of permits that had to be in place before starting work. Arriving in the afternoon and submitting my documentation package to the permit control room, I quickly settled into my allocated cabin just below the helideck. I slept like a log, awakening the following morning, rested and ready for the day’s work. I noticed a slight swaying movement when my feet hit the floor and put it down to the wind and large sea swell. Skipping breakfast to get started early, I dressed quickly in heavy, thick winter gear, then headed down the hall towards the airlock with substantial blast-proof, hydraulically operated doors leading to the walkway under the helideck. Stepping out of the airlock’s outer entrance to the circumferential walkway, I was thrown sideways through the air like a rag doll and slammed against the walkway exterior railing. The wind exceeding hurricane strength at such a height pushed me against the waist-level railing bars with such force that I could not move my body or legs, only my arms.

Looking down the one-hundred-and-thirty meters to the raging sea below, I feared the wind would push me through the openings between the horizontal bars of the walkway railing. My baggy winter clothing did not make the situation easier, giving the wind even more hold. The enormous accommodation structure and the pillars supporting the helideck also had a venturi effect. Pushed against and hanging on to the railing for dear life, I realised that the only way to get back to the door was to lay as flat as possible on the grating and pull my body forward using the steel vertical railing posts.

I drew a deep breath and slowly pulled myself down onto my side on the count of three. Facing the railing for what felt like an eternity, I pulled myself with difficulty back the six to eight meters towards the airlock, where I crawled through the outer doorway, battered and bruised from the violent encounter with the railing but thankfully still alive. If the wind had tossed me like a rag doll over the railing, nobody would have known for hours, and my body would likely have never been found.

After ridding myself of the winter clothing, I went down to the busy mess room, where they informed me that there had been multiple announcements over the onboard PA system during the night. They stated that all that non-life-saving work outside the accommodation was temporarily suspended due to the severe seventy-knot winds. I had slept through this. The experience was a stark reminder of the North Sea’s extreme conditions, and I realised how lucky I had been to escape death that morning.

Two days later, on the same platform, I experienced a fascinating example of the enormous amounts of energy produced by the giant platform. The complex had to flare off most of its gas production capacity and compressed volume in a connected pipeline for operational purposes. That evening, while working on the pipe deck drilling section of Oseberg A, there were heavy snow and sleet showers while all the high-pressurised gas was vented off and burnt by Oseberg B’s flare. The separation between the pipe deck and the flare nozzle was at least three hundred metres, and all the men outside had to wear earplugs and don ear defenders. The roar emanating from the gas flare-off was indescribable; the flame was well over a hundred metres in length and forty to fifty metres in width. The radiating heat was intense. My front became covered in sleet and snow when facing away from the blazing inferno while my backside steamed like a boiling kettle. It was an uncomfortable burning and freezing experience, and the solution was to turn around regularly, avoiding looking at the flare as it hurt my eyes. Night had become a bright orange day, and thankfully, a compassionate roughneck provided me with a pair of darkly tinted safety glasses as the flaring went on for several hours.

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