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OFFSHORE OPERATIONS & OUTLOOK Sakhalin project provides valuable lessons

By JL Thorogood, TW Hogg, AG Kalshikov, CJSC Elvary Neftegaz, BP AN EXPLORATION WELL drilled by a joint venture between Rosneft and BP in summer 2004 was the first success after a long period of no exploration activity and represented a step out into a new and untested exploration play.

Wells in Sakhalin involve a 7-month per- mitting cycle and a logistical supply chain that extends 3,500 miles to Singa- pore. The sea ice-free weather window lasts from late June to mid-November. Environmental restrictions stipulate that all mud and cuttings from below the 30- in. conductor, even though the well may be drilled with a water-based mud, must be recovered for disposal.

The team overcame a wide range of organisational, logistical, regulatory, environmental and technical challenges to drill the well in summer 2004. The les- Ann Smith photo sons learned were consolidated and The Sedco 600, seen here preparing for a basket transfer during a storm, had been cold-stacked for formed the basis for a successful season in 2005 with a different rig. a year before the 2004 Sakhalin operations and required modifications before startup.

INTRODUCTION September and remain intense through Uncertainties and unknowns plagued the the winter. early part of the project. Oil has been produced from Sakhalin since the 1920s. The northern town of THE ORGANISATION Planning and contracting became pre- Okha is built around an oilfield dating dictable once the joint venture was clear- from the earliest days. Offshore explo- Rosneft personnel contribute their ly defined and a budget approved. This ration was carried out in the 1970s and understanding of operations in Russia took place about 4 months before the 1980s, leading to the discovery of the while the BP heritage staff brings techni- well commenced. major fields being developed by the cal knowledge of safe operations in Sakhalin 1 and Sakhalin 2 Production remote harsh environments. REGULATORY ENVIRONMENT Sharing Agreements. The project team is responsible for exe- Russian regulations are extensive and When the first members of the project cuting the entire scope of the activity, complex. The permitting cycle takes 7 team arrived in Sakhalin in August 2003, including well engineering, operations months and requires lengthy calcula- other operators advised that there was a supervision, aviation, logistics, shore tions to estimate discharges. Fees are very low chance of being able to organise base, incident management, blowout assessed on the planned level of dis- and drill a well, starting from scratch, in contingency planning, health, safety and charges and penalties levied for less than 12 months. environmental compliance, cuttings dis- exceedance. Panels of reviewers are posal, permitting, IT systems and appointed by state bodies with oversight BP is a 49% shareholder in a joint ven- telecommunications. on environment, natural resources and ture with Rosneft, the Russian state oil industrial safety. Their task is to review company. The operations base is located Few members of the project team knew the applications critically. Small ques- in Yuzhno-Sakhalinsk in southern each other. The industrial climate in Sep- tions can and do cause significant delays Sakhalin. It is 8,000 km and 10 time tember 2003, after a round of lay-offs and to the granting of permits. zones from London and a 9-hour flight repatriations, made some key posts from Moscow. Operations take place off- impossible to fill satisfactorily, adding to Individuals in positions of responsibility shore at the extreme north end of the the team’s workload. for the operation have to be formally island, about 500 miles from the base trained in the Russian Safety Legisla- office. PROJECT SCHEDULE tion. Training runs for 3 days, ending with a written test and an interview. A Given the scale of the undertaking and The main logistics base at Moskalvo is license is renewable every 3 years. To the late start, it was clear in retrospect only accessible from early June to early assist compliance, a substantial effort that the 2004 exploration project was run November. The drilling location is clear had to be organised to train and examine of ice only in late June. Storms begin in to an extremely demanding schedule.

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OFFSHORE OPERATIONS & OUTLOOK key crew members during the mobilisa- tion of the environment. Permitting of mencing the well itself. Cuttings have to tion phase in Singapore. each well requires development of a full be skipped and shipped to shore. environmental and social impact assess- The precise method of importation of the ment, which must be approved at local The area first becomes clear of ice in rig was heavily researched because of and federal levels before being subject to early May, but there are unpredictable the different ways that the rig could be independent review in Moscow. instances of drifting pack-ice until mid- presented to the authorities and the sig- to late June. Severe storms and rapidly nificant difference in customs duties The wellsite is monitored by an inde- decreasing temperatures in the autumn that might ensue. In 2004 there was pendent contractor for compliance with result in a very clear cut-off date in mid- debate on the precise application of discharge approvals. October for un-winterised drilling units. Russian Tax Legislation in relation to the “Value Added Tax” applicable to well Environmental regulations prohibits the THE RIG construction operations in international discharge of any cuttings to sea in the The rig used in 2004, Transocean Inc’s waters. Russian Federation once the conductor has been set. Especially in Sakhalin, the semisubmersible Sedco 600, had been Customs regarded the rig as part of health of the local fisheries and protec- coldstacked for a year. Modifications Russian territory, but border guards tion of the Western Pacific Grey Whale were necessary to ensure adequate regarded the rig as an “international” population are paramount. lifeboat capacity. The ballast system was destination. Since the local airport was upgraded to meet standards of the Joint not an international gateway, helicopter Mud and cuttings are returned to the rig Venture, and wind walls were erected flights were prohibited without special by attaching the marine riser directly to round the drill floor and monkey board. permission from Moscow. This problem the wellhead with a pin connector. With The rig startup followed a thorough pre- wasn’t discovered until late, and obtain- this arrangement, the only protection contract audit. Audit findings were ing consent required intervention at the against shallow gas blowouts is the rig’s lengthy and required detailed planning highest levels. diverter system. This practice was the to accommodate in the shipyard re-acti- cause of serious incidents in the 1980s. vation programme. ENVIRONMENTAL CONDITIONS To conduct an operation with a pin con- nector requires a dispensation from com- High surface currents are a feature of There is extreme sensitivity to environ- pany operations policy. Under the terms the location. They hampered operation of mental issues in Sakhalin. Active non- of the dispensation, it is necessary to the Russian supply vessels. Although governmental organisations monitor drill a pilot hole to 20-in. casing depth to thought to be simply a problem associat- compliance with regulations for protec- prove absence of shallow gas before com- ed with deepwater operations, analysis

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OFFSHORE OPERATIONS & OUTLOOK pointed to vortex-induced vibration in and permit to work, were fully embedded • Onshore operations risk assessment to the marine riser with a high probability in the way that the crew worked. identify risks associated with shore base of fatigue failure unless preventive meas- and cuttings pit operations; ures were taken. A special task force In addition to maintaining a regular made up of staff from the Joint Venture, review of high-level project risks, a • Team health risk assessment to verify rig management, consultants and con- series of major risk assessments were that the working conditions for the proj- tractor engineering personnel met in Sin- carried out in targeted areas: ect team were fully evaluated; gapore and worked the problem at short • Well-specific risk assessment to identi- • Hazard and operability review of the notice. They proposed to wrap the riser fy technical hazards; well testing system; with 4-in. diameter mooring line to sup- press damaging vortices. The recommen- • Offshore operations risk assessment to • Risk assessment of the shallow gas dations were implemented and a real- identify hazards involved in the opera- emergency procedures. time monitoring system attached to the tions on location and on the ware barge; riser for the duration of the operation to verify the performance predictions.

Dramatic vibration was observed in 20- in. casing running string. In 2005, with more planning time, the riser was fitted with custom-designed strakes and the monitoring procedures repeated.

It was initially suggested by organisa- tions on the island that importation of the rig involved a lengthy and expensive process. However, a recent change to the regulations enabled the rig to be import- ed, complete with all installed equip- ment, and approved as a single unit.

Two key documents are required before a rig can operate in Russian waters: the Industrial Safety Declaration and the Permit to Use. The former is akin to the Safety Case. Obtaining the Permit to Use requires a technical inspection of the rig and testing of critical components and a review of key technical documentation.

The rig employed in 2005, the Transocean Legend, was mobilised from Brazil after a period in cold stack. Fol- lowing a detailed audit, extensive work on all rig systems was required in Singa- pore prior to acceptance. Some of the work continued through the tow north- wards and was completed just before deployment on location. OPERATIONAL HEALTH, SAFETY During both seasons, focus was placed on crew competence and training. Atten- tion was paid to the re-activation of the Contractor’s Safety Management System and a gap analysis carried out against the Joint Venture standards.

The drilling contractor held safety lead- ership workshops for the crews in Singa- pore. Company drilling supervisors were in place on the rig throughout the ship- yard re-activation and upgrade project. They remained on the rig during the tow northwards and used the time to ensure that the critical elements of BP’s Eight Golden Rules of Safety, lifting operations

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OFFSHORE OPERATIONS & OUTLOOK A specialist consultancy reviewed the During 2004 the team was heavily the port of Moskalvo with Billy Pugh bas- safety culture on-board the rig. A Jour- stressed as a result of the late start and ket transfer. The required permits were ney Management study was conducted to limited resources, resulting in a demand- obtained in good time in 2005. However, a ensure that the risks associated with ing schedule. Although the work was significant number of crew changes still long crew change travel times were done and a safe result achieved, the was required due to extensive sea fog in assessed and addressed. organisational model was clearly unsus- the area in early summer. tainable. Immediate steps were taken to Critical safety-related areas — such as re-constitute the team on a rotational Apart from being 500 miles north of the aviation, both fixed and rotary wing, basis as soon as it was clear that there main operations office, the island is 3,500 marine operations, driving and lifting were to be further operations in 2005. miles from Singapore. One-way mobilisa- activities — were subject to assessment tion of the rig to location, including cus- and approval by specialist teams. REMOTE AREA LOGISTICS toms clearance and inspections, requires at least 35 days. All equipment already Workplace safety at the cuttings pit was Crew changes involved flying people on the island were committed to other a major concern, and the services con- from the UK, US, Australia and Indone- operators. Because of the taxation impli- tractor prepared written procedures for sia to Yuzhno-Sakhalinsk and then by cations, none of this equipment was all activities. Once the equipment was set charter to Okha. A formal Journey Man- accessible to the Joint Venture operation, up on site, crews walked through the pro- agement study emphasised the need for even in emergencies. All equipment for cedures before a final walk-through by proper overnight rest for the crews prior the well had to be mobilised from Singa- the management team. At this point the to commencing work offshore. This was pore, including 320 drill cuttings bins for pit site was declared operational. achieved by scheduling boat journeys at the skip and ship operation. night or accommodating crews in a hotel The project team was responsible for overnight before flying them to the rig. Shipment of the equipment from Singa- providing first-line response to all inci- pore to location was accomplished using dents. An Incident Management Team In the 2004 season, resolution of the a ware barge. was set up and trained. In addition to issue of the border guards and the inter- all the normal contingency plans, national status of the local airport was The port of Moskalvo, on the Northwest authorities required a full blowout con- completed late in the operation. As a side of the island, 12 hours sailing from tingency plan and a contract for emer- result, a dedicated crew change vessel the location was the focus of the skip and gency support from a major well control was chartered at short notice from ship operation. Nearly derelict, it was organisation. Japan. Crew changes for the majority of being used for the export of large the well were carried out by boat from amounts of scrap steel to China. The

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OFFSHORE OPERATIONS & OUTLOOK Joint Venture established a small base size of hole section, rate at which skips casing string to be eliminated and 20-in. for handling the cuttings bins, stacking could be filled and handled by the rig casing point deepened. Although the casing and other items. There was no cranes (6/hour), number of bins per ves- operation started late and significant water or fuel at the base. In 2005 the sel (80), the sailing time to the port (12 downtime was experienced with the BOP ware barge was not available. An addi- hours) and the round trip time for truck and rig systems, once bedded down, tional supply vessel was chartered convoys onshore (4 hours). operations continued with rapidly instead. All the pre-mixed brine was pre- improving efficiency. pared in Singapore and shipped up in the Five hundred bins were fabricated on rig and vessels. short notice. They were shipped from the KEY LESSONS LEARNED rig, unloaded from the boats at the shore Despite the complexity of the logistical base and onto trucks for transport in 8- • Staffing a project team can take 3 to 9 operation, neither in 2004 nor 2005 was vehicle convoys 32 km to the pit site. In months. Considerable care is required to there any downtime on the rig waiting for 2005 the number was reduced to 250 ensure that the organisational model is supplies or missing equipment. because it proved possible to ship whole sustainable. mud ashore in supply boat tanks. SKIP AND SHIP • Late start in a tight employment mar- Environmental and governmental regula- ket exposes a project to significant risk. An environmental and social impact tions limited the choice of drilling fluid • Drastic prioritisation of activities may assessment for a well won’t be approved chemicals. Oil-based drilling fluids are be required to ensure that the essentials without prior approval of plans for dispos- currently not allowed from floating are in place before operation start-up. al of the drill cuttings. There was a choice drilling units. A KCl polymer mud was between land farming and burial in pits. chosen. • Environmental regulations can impose Eventually, the latter course was chosen. demands on the operation that require This was the first occasion that a 26-in. additional measures to ensure opera- The pits were excavated and lined and surface hole section had been contained, tional safety. sealed under specialist supervision. and it alone accounted for 35% of the Eight shallow wells were drilled around total volume. Each cuttings skip had a • Extension of the weather window past the site to monitor for possible ground- full capacity of 3.5 cubic meters. The esti- established limits requires winterisation water contamination. mate of the number of skips was based of the rig and careful analysis, planning on filling to between 75% and 80%. The To determine the number of cuttings and rehearsal of operational procedures. mud on cuttings value was projected at bins, account was taken of the length and 65% cuttings and 35% drilling fluids to • To function reliably, rigs taken from mud. Comparing actual volumes with the cold stack require more detailed pre-con- prediction suggests that the number of tract technical audit than is normally skips used was considerably less in the possible to carry out when in cold stack. upper hole sections. This is attributed to • Putting a rig to work in Russian waters losses along with dispersal of mudstones requires an Industrial Safety Declaration into the drilling fluid. Some whole mud and granting of a Permit to Use. was transferred to a supply vessel, pumped into cuttings bins at the quay- • Although the water depth in the area is side and mixed with cement before being only around 100m, the high currents cre- discharged into the waste pit. The 12 ¼- ated a problem of vortex-induced vibra- in. section incurred more clean-up than tion of the riser. the previous sections. • Permitting of operations in frontier THE OUTCOME areas can present unexpected surprises that take time and high-level intervention The 2004 well was a rank wildcat. It was to resolve. Local permitting expertise is the first to be drilled in the Deriugin essential. Basin. There was considerable uncer- tainty about the pore pressure and frac- • In a zero discharge environment, skip ture gradient regime. Provision was and ship of water-based mud and cut- made for running a 16-in. string to guard tings is feasible. against possible complications associat- ed with a slump zone. The operation • Careful planning of crew changes using started late because of permitting journey management specialists was delays. Some mechanical problems were essential to manage the safety risks encountered, some rig downtime was associated with long travel times. experienced, and there was slow drilling • Despite the complexity of the operation at total depth. Operations were complete and distances involved, planning enables by early October. the operation to be conducted without The well in 2005 was drilled some 25 km logistics-related downtime. from the 2004 well. Its design benefited This article is based on IADC/SPE paper from the engineering lessons learned #99044, presented at the Drilling Conference from the 2004 season, enabling the 16-in. on 21 Feb in Miami Beach, Fla. I

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