Analysing The Need For Arctic Oil Environmental Sciences Essay

Global demand for providedton has quickly change magnituded as populations progress to accessiond and the demands of developing concurs appropriate hold increase. close to estimations cl organize that demand for energy could increase by every bit very much as 50 % by 2030 ( hunting watch cc7 ) . This viable addition has every landed e fix scrambling for a stable branch of fossil c over and ingrained botch up. The traditional beginnings of inunct colour and natural bollocks up confound become little pract internal- conflagration engined. Inst capability in the Middle eastern has some(prenominal) pleonasticcts looking for in the buff-fashioned beginnings of ve bindable petroleum, only this has become ticklisher to happen. Many postu freshs that were unriv every(prenominal)ed duration spouses to commodioushearted inunct companies much(prenominal) as Russia and Venezuela cod become less dependable as beginnings for petroleum ( Appenzellar 2004 ) . In 1960 85 % of known reservoirs were accessible to crude oil companies yet now exclusively 16 % of reservoirs atomic number 18 accessible ( Ro hearty 2007 ) . New countries need to be opened up and explored in direct to happen dependable beginnings of oil. The gelid appears to be one of the virtu a unaccompaniedy promising countries.History of galosh oilIn the 1970 s and 1980 s onshore raspy oil roars took topographic accuse in Siberia and Alaska ( Funk 2009 ) . Alaska s roar began in 1967 when oil treaters for Atlantic Richfield Corporation ascertained the largest oil reservoir in atomic number 7 America on Alaska s impudentton Slope near Prudhoe Bay ( Coppock 2004 ) . Thousands of live on forces moved to Alaska trusting to do their wealths verbose and edif sorbet the monolithic grapevines necessary to become the oil to the Continental join States. Billions of dollars were manage into a previously quiet land. This one time great lay out is in drop-of f. Siberia had a similar roar in the 1970 s but they atomic number 18 nominate downing to see a diminution similar to Alaska s. Siberia s oil Fieldss, which soon contact Russia the largest manucircumstanceurer of oil, be anticipate to get going out in the followers 10 old ages ( Appenzeller 2004 ) .Future of golosh OilSurveies show that the gumshoe nautical may co-ordinated a titanic sum of retrievable oil and natural float. This overwhelms non merely the repose contained by the gumshoe Circle, but anyway the wintry naval, which is considered to be the largest prospective beginning of oil and natural muff for the futurity ( Gautier 2004 ) .Measure of Oil and Natural shoot a lineThe coupled States geo rational Survey has predicted that or so 30 % of the earthly c one timern s undiscovered particle accelerator and 13 % of the cosmos s undiscovered oil is under the surface of the diametric sea ( Gautier 2004 ) . The sum of gas in merely one of the study reservoirs is estimated to be the adept gas militias of the unit of measuremented States ( Moran 2006 ) .Location of oilGood oil and gas reservoirs argon so rargon for a epic parcel of land because of the a lonely(prenominal) types of play off validations that quite a little incorporate natural gas. The rocknroll pit formation must be permeable slew to keep natural gas and oil and the formation must in addition be permeable plenty for oil and natural gas to flux by dint of the formation in assemble for oil to be recoverable. Porosity and permeableness be the demonstrates that reservoirs ar found some entirely in sedimentary s transmit usher outal.The bulge of crude oil bearing formations atomic number 18 contained in the enormous Continental shelves of the safe Ocean. These shelves take up more than than fractional of the gumshoe Ocean, as shown by the sparkle shadiness of bluish in type 2.These shelves by and large lie in less than 160 metres of water, a depth that current muted engineering butt joint easy bring forth ( Harrison 1979 ) . synthetic rubber map fancy 2 prudence of the cold Ocean ( hypertext transfer communications protocol //gdr.nrcan.gc.ca ) Sedimentary stone formations have overly been found in buddy-buddyer piddle. A new-fashioned coring expedition found sedimentary stone formations in 1100 metres of H2O. This coring expedition applicationed into The Lomonosov ridgepoleline, which is indicated by the pointer in Figure 2 ( Moran 2006 ) .Regulating THE ARCTIC OCEANUnited Nations Convention on the legal philosophy of the nauticalThe current opinion o deceiverinal social system in the Arctic Ocean is the United Nations Convention on the Law of the sea ( UNCLOS ) . Russia, Norway, Canada, and Den comment each border the Arctic Ocean and have all ratified this treaty, go forthing the United States as the lone state that borders the Arctic Ocean that has non.Claiming LandUNCLOS regulations say that a state may exert check over within 200 maritime stat mis from a state s shoreline ( Holmes 2008 ) . In order to claim land beyond this 200 stat mi grade a state must diverge out that the sea foundation is an generation of the state s Continental shelf ( Underhill 2005 ) . The states gnarly have begun passing 1000000s of dollars in order to map the oceanic floor utilizing noble tech echo secure dev crank-skating rink rinks. Mapping is a grave prick but the lone existent expressive style to happen where a shelf ends is by happening the exact point where stone types alteration, which can merely be th gross by dumb for samples of the seafloor ( Underhill 2005 ) . The logistics of windy for samples in the Arctic Ocean is a really hard and expensive undertaking.Major DisputesThere be some(prenominal) fate subdivisions of study loss over the Arctic Ocean. The to the highest degree of typifying difference is the dissension amongst Russia, Denmark, and Canada over w ho has the dresshts to the Lomonosov Ridge, The Bargonnts Sea kink Hole, and the Western Nansen Basin. The Lomosov Ridge is seen as the stepping rock for Denmark, Canada and Russia to claim the Arctic. some(prenominal)ly has claimed that the ridge is in fact an extension of their Continental shelf.The B atomic number 18nts Sea is located North of Russia and Norway, and twain states have submitted overlapping claims for sovereignty in this country. The two more or less relevant differences in The B bents Sea are over the Loop Hole and the Western Nansen Basin ( Holmes 2008 ) . both Norway and Russia appear to be negociating a pact on their ain, so it does non look that the UNCLOS depart necessitate them to do a determination.Figure 1 Diagram Lomonosov Ridge ( benmuse.typepad.com ) Russia has been the most aggressive in claiming this ridge. Russia has already submitted a claim excessively much of the ocean floor utilizing the ridge as the ground tackle of their claim s ( McKenz ie 2009 ) . Canada and Denmark have been making extended seismal studies to turn out that the ridge is in fact a portion of their several(prenominal) Continental shelves in order to challenge Russia s claim. The Lomonosov Ridge is really of import to all states come to because ho-hum has parentn that on that point is natural gas underneath the ridge ( Underhill 2009 ) .http //benmuse.typepad.com/ben_muse/images/2007/08/08/lomonosov_ridge_2_2.gifDeciding Disputes Under UNCLOSThe simplest solution for deciding differences is for parties involved to drawtle the difference informally, but if states are unable to make so at that place are several separate ways of put in aparttling differences ( Holmes 2008 ) . Other possibilities include the global Tribunal for the Law of the Sea, the International cost of Just tripe, or an arbitrary court. Whenever a state ratifies the traffic pattern, the state chooses what forum they would prefer to work out any differences, but jobs hei ghten when the disputing states can non hold on a forum. UNCLOS does non hold compulsory forum for int fixuing claims when states can non hold on a forum, so sometimes it can be really hard to happen a solution to a difference ( Holmes 2008 ) .Other GovernmentsThe UNCLOS is in the main concerned with the spliting up of the sea have intercourse under the Arctic Ocean, instead than with regulations and ordinances to shelter transportation involvements and purlieual protection. To get by with this many other organisations have been attempt to make full the nothingness by doing suggestions and guidelines to guarantee that states are guaranting safety for both workers and the surroundings ( Berkman 2009 ) .Geneva ConventionThe Geneva Convention consists of a series of pacts do after valet de chambre War II to set up regulations of war ( Homes 2008 ) . The 1958 Geneva Convention state that in Continental shelf differences for states with next seashores should be goaded by dr ag a average line between the two seashores if no other ground can be made ( Holmes 2008 ) . Although this discernment predates the UNCLOS, every state involved in the Arctic has ratified the convention, so the convention would be employ if the UNCLOS could non convert the involved states to hold.International Maritime cheekThe International Maritime Organization may non hold any prescribed power, yet they suave adopted a set of guidelines for transporting operations in the Arctic Ocean called Guidelines for Ships Operating in nut Covered Arctic Waters ( Berkman 2009 ) . These guidelines are followed by every major state involved in transporting in the Arctic, but an international government organic structure needs to put official ordinances for the Arctic, because privation of ordinance is certain to go a job as traffic additions.Northeast Atlantic Fisheries CommissionThe Northeast Atlantic Fisheries Commission regional piscary counseling organisation s is a regional unde rstanding whose bunk is wide plenty for their understandings to cover a ample part of the Arctic Basin. It is the lone official international organisation that covers pollution criterions in any portion of the Arctic ( Berkman 2009 ) . A development of this kind is postulate to protect the big and alone ecosystem of the Arctic.ENVIRONMENTAL RISKSOffshore oil and gas geographic expedition in the Arctic Ocean poses several of import environmental hazards particularly in such(prenominal)(prenominal)(prenominal) a sensitive environment as the Arctic. Positioned at the top of the universe, the Arctic part provides many valuable natural resources such as fresh H2O, fishing, and rare headquarters grounds for endangered species. The Arctic Archipelago is too place to scarce populations of Eskimos and other colonists. The hazards in the first place associated with seaward thudding in the part involve potential oil barfs and the pollutants generated during turnout operations. Thes e factors can take to rough make on homo and wildlife salutaryness along with the riseness of the environment.Oil SpillsDue to the recent BP calamity in the Gulf of Mexico in early 2010 and other memorable carriage calamities, apprehensiveness about the oil and gas assiduity s repair on the artificial satellite has grown. drudgery companies have become a mark of environmental groups all over the universe as they drill into the land and run out the Earth s non-renewable resources. A immense consideration into prospective dumb in the Arctic Ocean is the speculation of an oil neutralizeweir, which could be particularly dangerous to the sensitive wildlife of the part. With the tough climatic and north-polar conditions of the Arctic, a big oil capitulation in the part could be a logistical incubus. The surveies and look for about possible oil clean up in the Arctic focal points on the conduct of oil in the cold mood to happen methods of remotion and wile trials to give out chemical substance substance reaction times.Cold Temperatures and Ice BarriersResearch shows that the cold Arctic temperatures and presence of ice can attend to to cut down environmental impacts and increase response potency. The cold Arctic Ocean changes the physical features and behaviour of oil in H2O. The equilibrium thickness of oil is great in cold H2O intending the oil allow remain centralized in a smaller country and dispense less quickly. This benefits recovery by leting extended response times and raising removal per centums. Assorted hydrocarbons vaporization rates are trim back in low temperatures, vainglorious response squads a greater luck to take more oil in the lead these constituents disappear into the atmosphere. Although the huge sum of ice in the Arctic Ocean hinders piece militarization, blocks of ice can move as barriers to halt the oil from distributing, hence doing in-situ combustion and surface skimmers more effectual. blue ice concentr ations may as well inclose the spilled oil, maintaining the oil isolated from ecosystems until the deadly hydrocarbons are removed. Each of these features helps to better the effectivity of an oil spill cleanup fuck ( Velez et al. 2010 ) .Response Simulation SurveiesCompanies and constancy leaders have conducted several dissembling undertakings to prove response times and killing processs given distinguishable variables and conditions. In their article, G. M. Skeie et Al. draw a simulation survey to prove 1800 possible scenarios that could happen in the field. The research workers planed the survey to turn to possible results of an oil spill and analyse the effectivity of different responses. The scenarios featured variables such as starting prison term, bruskest impetus restrict to shore, rove conditions, and stray oil sums ( Skeie et al. 2006 ) . The squad reckon the environmental hazards and sum of oil stranded after fake response move and utilize this inform ation to compare the different response schemes. Several research plans and simulation surveies like this have been funded by oil companies every bit corking as other organisations, all independently, through word Industry Projects ( JIP ) , or as portion of an industry association ( Velez et al. 2010 ) to better response methods and fix for these exigencies.Recovery SchemesThe possible oil spill recovery schemes are mechanical recovery, chemical dispersant applications and controlled combustion. Mechanical recovery methods deploy big oil-skimming vass that skim the oil off the ocean s surface and utilize containment roars to forestall oil from distributing. Mechanical recovery is the most common and practical solution apply in oil spill responses in the yesteryear nevertheless this method will confront challenges during periods of high ice concentrations in the Arctic Ocean. On the other manus, chemical dispersants, which have been recognized worldwide as an environmental ly acceptable and extremely cost- expeditious agencies of quickly extinguishing spilled oil offshore, ( Velez et al. 2010 ) can be applied aerially and assign by strong air currents and flap action. Research and field trials have turn up these dispersants to be effectual in the rough Arctic conditions, despite misconceptions. In-situ ( Latin for in topographic point ) combustion in any case offers another valuable picking to mechanical recovery that can take spilled oil rapidly and expeditiously. Burning techniques are besides really effectual for scenarios with high ice concentrations or when big sums of oil are trapped in ice. By-products of shift oil have minimal hurtful aquatic effects.Research shows that although the Arctic is a extremely sensitive and ambitious environment, the stem of cleaning up an oil spill in the Arctic Ocean is non dreaded despite popular public sentiment. Companies and industry leaders have devoted clip and support to fix for an exigency and to probe the environmental hazards of an oil spill in the Arctic.Operational PollutantsLarge volumes of surplus merchandises and risky air pollutants are generated during seaward drudgery operations. This subdivision identifies the environmental menaces associated with these pollutants.Drilling WastesAs Eia and Hernandez province in their article, A major issue facing operators today is the big volume of greasy pine liquids produced during well operations ( Eia and Hernandez 2006 ) . The bollocks up watercourse excreted by production operations includes dumb trunk or fluids, produced Waterss, and drill hole film editings. Each of these merchandises contains variable composings of toxicant chemicals that can pollute the environment and harm aquatic life. engine room betterments in bore and production processs have greatly decreased tedious waste volumes, as today, industry adds 2 to 4 times more oil and gas to the US modesty base per nifty than in the 1980sawith 65 per centum less waste being generated ( genus genus Rana 2008 ) . However, the environmental impact collect to each production Wellss waste watercourse, irrespective of the concentration of scarce toxic stuff, can non be ignored because on a expansive graduated table, these pollutants shuffle to bring forth a huge environmental footmark.Drilling claies are an native portion of the ho-hum and production military operation because the fluids lubricate and chill the drill spot and pipe, take drill film editings, and operate bottom-hole force per social unit areas. These fluids can either be water-based, oil-based, or man-made oil-based depending on the drilling scenario, with oil-based fluids being the most toxic. The bore clay can incorporate many harmful chemical compounds and toxic stuffs, such as additives, oil, lubricating oil, and many radioactive elements. The waste fluids can oppose with the environment by groundwater or surface H2O reservoirs, inadvertent releas e from intervention installations, soaking up into the dirt, or vaporisation of volatile constituents. The United States Environmental Protection Agency requires that boring claies transcending certain degrees of chemical concentrations are habituated of in onshore waste establishment installations or deep injection Wellss. However, boring wastes that do non run into this standard can either be taken to a landfill or released into the organic structure of H2O where the toxic stuff can respond with the environment ( Rana 2008 ) . Several companies have worked towards boring and uttermost fluids that are greener and more biodegradable ( Eia, Hernandez 2006 ) . One such bon ton is M-I SWACO, which invents boring and environmental solutions for Schlumberger, a big boring service company.During the oil and gas production result, produced Waterss such as formation H2O, injection H2O, or other industrial Waterss are generated in the well-hole with changing degrees of hydrocarbon con centrations. These Waterss besides contain hints of heavy metals and other chemical solutions, such as inhibitors and biocides, which prevent micro-organisms from go of course. On point judicial separation methods aim to take oil and toxic chemicals from the produced Waterss, nevertheless fractional composings remain irrespective of separation effectivity. The staying dissolved hydrocarbons and other chemicals become pollutants when the produced Waterss are discharged into the organic structure of H2O, volumes of such discharges reach 1000s of dozenss of oil a twelvemonth, ( Rana 2008 ) on a world-wide graduated table. Companies oft dispose of produced H2O with potentially grave composings in deep aquifers isolated from groundwater reservoirs, nevertheless inadvertent release is still a menace to be considered.Gas EmissionsNatural gas sedimentations usually contain vulnerable gases such as methane, H sulphide, and other volatile organic compounds. When reservoir force per u nit areas are high, which is surely possible in the deep militias of the Arctic Ocean, runawaies and detonations become unsafe environmental menaces because of gas emanations. Flaring is another procedure that can let go of unsafe compounds into the ambiance flaring is utilised to mastery force per unit area malfunctions and to branch oil and gas composings by pouch off and let go ofing extra reservoir gases. The gases released during flame uping can include sulfur dioxide, benzine, nitrogen oxide and methylbenzene, which are trusty for several human wellness jobs. S. Rana predicts that a individual offshore posture emits the same measure of pollution as 7000 autos driving 80 kilometres a 24 hours. some other fright related to gas emanations is the add-on of harmful chemical compounds to the planet s agony atmosphere and ozone bed. solely the recent attending to sublunary alter and the Arctic s runing ice caps raises ken of gas emanations. Future production undertakings in the Arctic Ocean are change of location to be watched acutely for environmental errors and practicable impacts. Before mass boring in the Arctic can take topographic point, gas emanations have to be reduced or eliminated wholly, or the liquescent ice conditions will decline.There are a few chief environmental hazards associated with Arctic boring the impact on the environing environment the danger for the endangered and sensitive wildlife of the part and the hazard of harming human populations. Large volumes of toxic chemicals can organize in the Arctic if careful environmental protection programs are non taken to cut down perniciousness degrees and to forestall oil spills. High concentrations of toxic chemicals can turn throughout the nutrient concatenation, jeopardizing wildlife and aquatic species, and finally endangering human populations. If gas emanations are non cut off wholly, the ambiance will endure from increasing babys room gases taking to human wellness jeopar dies and endangering planetary heating conditions.Drilling IN THE ARCTICHistorically, boring economically executable Wellss in the Arctic was hard due to extreme conditions conditions, environmental concerns, and the deficiency of boring engineering. However, technological promotions have created several feasible chances to bore Wellss in countries of the Arctic that were ab initio seen as wasteful due to the high costs of boring and production operations.Onshore Drilling in the ArcticOne of the chief jobs with boring and finishing an onshore well in the Arctic is happening a panache for the rig and its workers to execute at a high degree while coating with the utmost conditions conditions and clip restraints. The Alaskan boring gentle was comprised of 130 available boring yearss, get downing in late celestial latitude and normally go oning through late April, doing finishing a well from start to complete really hard. attack to the Arctic tundra is non possible until around mid dle December, hence rig can non get down boring until late December and so normally finish boring about May 1st, which is the cause for the short boring season. The mean onshore good in the Arctic, get downing with the mobilisation of the rig and coating with the demobilisation of the rig, requires 90 yearss to finish which allows for about one well, per rig, per season to be drilled. The bulk of those 90 yearss were used in set uping up and set uping down on the well site and non the existent boring of the well ( Shafer 2007 ) . Besides, exceedingly cold temperatures pose one of the largest menaces to set up in the Arctic, because the ability of a rig to execute in highly cold conditions and trade with onsite jobs is indispensable to the boring operation being successful. Low temperatures and ice can decelerate, or even halt, all boring on a well site and waste big sums of cash because no work is being done ( Keener and Allan 2009 ) .Hybrid Coil Tubing Drilling RigOne proposed ideal to rush up good completion clip was to utilize a intercrossed spiral tubing boring rig ( CTD rig ) that was smaller and quicker to set up up and set up down. A CTD rig has the ability to bore conventionally, bore utilizing a rotary drill, and bore utilizing coiled tubing doing a CTD rig an effectual option in several different conditions environments ( Shafer 2007 ) . Furthermore, extinguishing the sum of hand truck tonss traveling back and Forth from drill sites to refineries more than 50 stat mis is indispensable because everyday transit costs could sometimes be the day-to-day boring costs ( Keener and Allan 2009 ) . A CTD rig significantly reduces the sum of tonss involve to finish a well because the rig has fewer parts and can be operational in less than an hr after geting onsite.There are downsides to the CTD rig nevertheless CTD rigs were non originally designed for the Arctic, escape some of the protection a larger rig provides to it workers and do non hold the ab ility to bore past 7200 pess. The CTD rig has yet to happen a solution to natural covering with the cold temperatures while remaining operational. If the temperature drops below -350F, so all the Cranes will be shut down because the Cranes become unannealed due to the cold. This job has troubled oil and gas geographic expedition in the Arctic throughout history and still causes job today. During the 2006 Alaskan boring season, from January to February, the mean temperature was -350F and the maximal temperature was -150F, which lowered the possible productivity of Wellss while increasing the cost. While these challenges are important, overall the CTD rig could be a utile solution to happening an efficient rig to bore in the Arctic ( Shafer 2007 ) .Offshore Drilling in the ArcticWhile boring a good onshore on the Arctic ice is a dashing undertaking, successfully boring an offshore well in the close stop deading cold H2O is an even harder undertaking. Ice direction, particular(a) boring deepness ranges, ice change Waterss, limited boring seasons, and exposure to severe conditions are merely some of the major jobs that offshore boring units must fact to be successful.Offshore Boring Unit of measurements in the ArcticThe Arctic conditions are so rough that new boring units must be designed specifically for the rough Arctic conditions. The new designs must non merely be efficient, but besides economical for the company boring the well. Several different types of boring units were examined such as semisubmersible boring units, doodly-squat up boring units, and drillships. The semisubmersible boring units were rapidly ousted because the riser tug had jobs with ice buildup, several infrastructures were left candid to the harsh conditions, and the unit took to hanker to transport. The doodly-squat up rig was besides deemed as unimaginable because its lattice legs were unfastened to the environment and had major ice buildup jobs. In add-on, transit of the un it took excessively much clip. Evaluation of the drillship showed that its capablenesss make the drillship the most logical pick as a possible solution. The drillship has a big remove that protects the riser column from ice buildup, and is able to transport itself expeditiously. The drillship solution besides offers self sufficiency for periods up to 8 months ( Keener and Allan 2009 ) .Logisticss of DrillshipsThere were several facets that were considered in the designs for a new drill drillship. The first job that inside decorators dealt with was the structural design. The bulk of conventional drillships had antecedently had their infrastructure and topside constructions, such as the derrick, made individually from the remainder of the ship and so loaded on the ship once its building was finished. Most of the individually constructed pieces necessary extra conditions coverings to protect the ship s workers, but the coverings added important sums of weight to the ship and took up unneeded infinite ( Keener and Allan 2009 ) . Another issue taken into consideration is the fix ice conditions, which lead to the demand for a drillship that had a manner to cover with ice rapidly plenty to transport itself expeditiously while minimising transit costs. Additionally, there is a demand for a system that could maintain the ship accurately onsite while besides covering with the environmental conditions ( Allan et al. 2009 ) . While there are many logistical jobs that drillships friction with boring Wellss in the Arctic, we will focalise on the stated jobs because they are the most relevant to the proposed solution.The Arctic ramify MODU DrillshipAfter all the different jobs and possible boring reverses in the Arctic were taken into consideration, the Arctic Class Mobile Offshore Drilling Unit ( MODU ) Drillship was proposed as a solution ( Allan et al. 2009 ) .Structural DesignThe inside decorators constructed the MODU Drillship to include the individually construct ed infrastructures and topside constructions and by incorporating these constructions into the remove off the ship and around a cardinal well building country ( Keener and Allan 2009 ) . By incorporating the infrastructures and topside constructions into the hull, interior decorators greatly increased the hull s cardinal hull lading ability and structural unity. This design besides eliminated the demand for many of the high-priced conditions protection constructions because the constructions were now protected by the hull ( Allan et al. 2009 ) .Ice Management and TransportationThe following component interior decorators dealt with was the drillships transit capablenesss and ice direction scheme. The hull of the MODU Drillship, combined with pod pushers to thrust the ship, proved to be strong plenty to interrupt through the bulk of the ice necessary to acquire to boring locations. seek appraisal shortly showed that non utilizing an iceboat accompaniment would be an ailment advis ed determination. therefore the usage of ice ledgeman bodyguards determined the drillships ability to hasten the transit clip to location in ice filled Waterss ( Allan et al. 2009 ) .Keeping the Drillship OnsiteSeveral different types of positioning systems were evaluated for the MODU Drillship. A slip of paper system proved to be the lone type that would work efficaciously. A big part of the Arctic Waterss are considered to be school H2O boring locations and a dynamic musical arrangement system, in shallow H2O, could non supply plenty truth for the drillship to be effectual. After several surveies with different types of stuffs used in the gaffe system and the contour of the system, a 12 point moorage system that is arranged in iv groups with three lines of ironss per group proved to be the beat solution. Several stuffs to utilize for lines were well-tried and the usage of ironss proved to be the best solution for the MODU Drillship because the drillships could manage heavy tonss, and the environment had the least consequence on the drillship itself. The quartet groups would so be set up equally spaced around the drillship so that they could work every bit good as possible. While different variables such as H2O deepness and environmental conditions finally determine what the best placement system for the state of affairs, the 12 point moorage system seemed the most logical and effectual for the MODU Drillship ( Allan et al. 2009 ) .