An Approach To Oil Spill Containment For Floating Drilling Operations In Canadian Beaufort Sea Pack Ice Conditions

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1 For Floating Drilling Operations In Canadian Beaufort Sea Pack Ice Conditions Canada - US Northern Oil and Gas Research Forum Calgary, Alberta December 2 nd, 2010

2 An Overview An Overview Of Same Season Relief Well (SSRW) Capability Related Issues A Proactive And Reactive Approach To Containment A Discussion Of Six Key Areas To Be Considered When Assessing Oil Spill Containment Options For Floating Operations In Arctic Pack Ice An Overview Only More Comprehensive Review Of This Issue To Be Addressed in The NEB Arctic Offshore Drilling Review 2

3 Same Season Relief Well (SSRW) The History In The Canadian Beaufort Beaufort Sea Steering Committee Report Established in 1976 The aim of this policy was to develop a regulated operating season that would allow a relief well to be completed in the same season thus ensuring that the well did not flow uncontrolled under the ice all winter Since 1976, all Operators of Canadian Arctic floating drilling operations drilling on Federal Lands have been governed by this policy. During this period, 39 wells were drilled without any environmentally damaging well control incidents The last floating drilling application (Kulluk 1990) was denied after a public review process due to issues related to relief well duration and blow-out rates 3

4 Same Season Relief Well (SSRW) Canadian Beaufort Example SHELF SHELF EDGE SLOPE 2008 / 2009 / 2010 Leases Exploration is moving northwards into deeper water, more challenging ice conditions and involving the drilling of deeper and more complex wells The ability to safely drill a same operating season relief well in this area is a function of: ice conditions, ice class of drilling system (marine support + drillship) and the associated well depth and complexity For many plays on the Slope, the duration of the relief well exceeds the operating season length and, as such, SSRW Capability, as previously defined, may no longer be viable 4

5 Same Season Relief Well (SSRW) Setting The Goal The recent change to a Goal Oriented Regulatory System requires a goal to be defined for what was previously referred to as the SSRW Capability Policy The goal should define the desired end state rather than the means of achieving the goal (i.e. a relief well) as is the case of the SSRW Policy Similarly, in a goal based regulatory system there is no single, correct solution to addressing a goal set by regulators While there will be much discussion and debate as regards the detailed definition of an appropriate goal, the general theme will likely be to mitigate any environmental impact by reducing the duration of the flow period 5

6 A Proactive & Reactive Approach NORMAL OPERATIONS PROACTIVE Reducing The Risk PROCEDURES, TRAINING & CULTURE ENHANCED WELL CONTROL EQUIPMENT WELL INTEGRITY LOSS OF WELLCONTROL REACTIVE Reducing The Flow ENHANCED MARINE CAPABILITY WELL INTETRVENTION / CAPPING DIRECT DISPERSANT INJECTION PROCEDURES, TRAINING & CULTURE ENHANCED MARINE CAPABILITY WELL INTERVENTION / CAPPING ENHANCED WELL CONTROL EQUIPMENT DIRECT DISPERSANT INJECTION WELL INTEGRITY 6

7 Procedures, Training and Culture As a function of both regulatory requirements and corporate standards, Operators utilize comprehensive management systems that drive procedures, training and culture For example, Chevron s Operational Excellence Management System (OEMS) is the systematic management of process safety, personal safety & health, environment, reliability, and efficiency to achieve world-class performance Risk Uncertainty Management Systems (RUMS) and Management of Change (MOC) processes are rigorously applied to both the planning and execution of drilling programs In-house well control schools and a dedicated Sub-Sea BOP Team are also utilized to further identify and reduce risks 7

8 Well Integrity With a goal of preventing a well control event the well design should accommodate the following capabilities: Surface casing and cementing program should not allow the potential for a environmentally damaging hydrocarbon breach to the seafloor. This will involve consideration of: Deep casing setting depths Comprehensive cementing programs Tubular design (pipe body & connections) Casing intervals should be positioned to ensure that excessive pressures are not experienced at the base of the previous casing string The casing design and the associated tubulars / connections should be capable of handling the maximum anticipated shut-in pressure that could be experienced during a well capping operation 8

9 Enhanced Well Control Equipment: Capability and Redundancy Conventional Sub-Sea BOP Stack Chevron Cameron 18 ¾ 15M AWKS Ram AWKS Safety Package Enhanced BOP systems, such as the Chevron Cameron Alternative Well Kill System (AWKS) ram - currently under development, may be utilized when both proven and approved by the regulator Redundancy can be provided by systems such as the AWKS Safety Package (shown opposite) or the ConocoPhillips Arctic Seabed Isolation Device (ASID) Further details on the AWKS and the AWKS Safety package can be found at Chevron SSRW Capability Submission 9

10 Direct Dispersant Injection The Macondo experience coupled with recent dispersant research indicate the potential benefits that could be attributed to direct dispersant injection into the wellhead Dispersant injection assumes the use of a fully tested and approved dispersant for sub-sea use in the arctic Direct injection of a dispersant into the wellhead should allow for the following: DIRECT DISPERSANT INJECTION More efficient dispersion of the oil Less dispersant used Less oil should reach surface and thus may biodegrade naturally 10

11 Well Intervention / Capping The illustration opposite shows a well being capped from an Arctic Offshore Support Vessel (AOSV) other marine vessels may provide the same function With this capability in-field, and an appropriately engineered well design, it should be possible to cap the well and thus stop the flow Well capping operation being undertaken The AOSV could also be equipped to provide direct dispersant injection at the wellhead during well capping operations Detailed oil spill management plans, and associated techniques / equipment requirements, would be developed for the various generic oil spill scenarios 11

12 Enhanced Marine Capability High Ice Class AOSV High Ice Class Icebreaker High Ice Class Icebreaker With a capable arctic drilling system, drilling into early December should be easily achievable as previously demonstrated by the Gulf Beaudril Kulluk system A successfully capped late season spill may require to be tracked, contained and managed in winter operating conditions A marine fleet capable of winter operations may be required to support such activities and would likely comprise of : 2 High Ice Class icebreakers 1 High Ice Class AOSV or equivalent Logistics independence will be a key feature requiring significant levels of fuel storage for both marine and helicopter operations 12

13 Concluding Remarks The adoption of a Proactive approach to well control reduces the risk of an incident In the highly unlikely event of a loss of well control, a Reactive approach such as well intervention / capping can allow the flow to be controlled in a timely manner Key areas to consider in achieving these goals are: Procedures, Training & Culture Well Integrity Enhanced well control equipment Direct dispersant injection Well intervention / capping Enhanced marine capability 13