ExxonMobil's Environment Policy
The Corporation is committed to continuous efforts to improve environmental performance throughout its operations.
Accordingly, the Corporation's policy is to:
- comply with all applicable environmental laws and regulations and apply responsible standards where laws and regulations do not exist;
- encourage concern and respect for the environment, emphasize every employee’s responsibility in environmental performance, and foster appropriate operating practices and training
- work with government and industry groups to foster timely development of effective environmental laws and regulations based on sound science and considering risks, costs, and benefits, including effects on energy and product supply;
- manage its business with the goal of preventing incidents and controlling emissions and wastes to below harmful levels; design, operate, and maintain facilities to this end;
- respond quickly and effectively to incidents resulting from operations, in cooperation with industry organizations and authorized government agencies;
- conduct and support research to improve understanding of the impact of its business on the environment, to improve methods of environmental protection, and to enhance its capability to make operations and products compatible with the environment;
- communicate with the public on environmental matters and share its experience with others to facilitate improvements in industry performance.
- undertake appropriate reviews and evaluations of its operations to measure progress and to foster compliance with this policy.
Extended reach drilling
Extended reach drilling (ERD) has reduced the need for offshore platforms in some parts of the world. On the Sakhalin project, new ERD technologies have allowed for field development from land by drilling up to 12 kilometers or 40,000 feet horizontally under the Sea of Okhotsk. Extended reach drilling technology reduces underwater noise and limits the offshore presence.
Global Use of Centrifugal Cuttings Dryers
ExxonMobil uses environmentally compatible base fluids for non-aqueous drilling fluid cuttings discharged at sea. To reduce the amount of fluids discharged on cuttings, several technologies may be employed. The standard technology used on our offshore rigs that discharge non-aqueous drilling fluid cuttings to sea is a centrifugal cuttings dryer. In Malaysia, ExxonMobil reduced fluid on cuttings discharge 10 years before regulations were adopted demonstrating its global leadership in this area.
Water conservation and recycling
As part of our project planning, we assess the impact of our activities on freshwater availability and demand. We use a wide range of approaches to reduce water use and preserve water quality through on-site recycling and water re-use, using produced water, employing processes to decrease water needs, and appropriately treating wastewater streams prior to their discharge.
In Indonesia, 100% of the recovered drilling water is recycled. Annually, over 125,000 barrels of recycled water are reused for drilling fluid. Rainwater is also captured in a separate container for reuse. During the rainy season, pits are covered to divert rainwater, which allows us to build smaller pits.
In Western Canada, hydraulic fracturing is used to recover reserves from shale gas wells. To reduce the amount of surface water required during these large stimulation operations, a water-recycling program has been developed to capture the flow-back and reuse it for future hydraulic fracturing. During the initial year of operation, approximately 82,000 barrels of water will be recycled.
In Nigeria and Germany, rain is harvested to make drilling fluid. During heavy rain days, up to 500 barrels can be collected, and in most cases the rainwater accumulated exceeds the water needed at the rig site.
To reduce freshwater usage during the dry season, 33% of drilling fluid and 85% of completion brine are recycled via well-to-well transfers in Chad. During a nine month period, our drill team recycled over 50,000 barrels of fluid.
Technology solutions — Fast Drill
ExxonMobil’s drilling rate has improved more than 80% since introducing the Fast Drill Process. This results in an annual energy savings equivalent to removing 1200 cars from the road. The additional reduction in fuel consumed means a proportionate decrease in air emissions.
Reduced Waste Material
Improved borehole stability and vibrations management have resulted in smoother gauge-sized holes in ExxonMobil’s drill wells. Consequently, the annual volume of cuttings generated has been reduced by 10% — approximately 3,000 pickup trucks of cuttings.
Drill cuttings disposal
On offshore rigs, after treatment, cuttings are discharged to the sea where they disperse. Studies have confirmed there are no long term impacts to the environment from discharging treated cuttings offshore. Offshore discharge avoids the need to transport cuttings to shore thus eliminating air emissions and associated personnel safety risks as well as onshore land farms. In cases where regulations do not allow discharge to sea, cuttings are shipped to shore and disposed of on land using approved processes.
Based on geology and infrastructure, drill cuttings can be injected into subsurface formations where they are permanently isolated. This is most suitable for multiple well programmes. Cuttings injection technology has been used safely and reliably to inject cuttings in offshore Eastern Canada, Norwegian North Sea, offshore California and Sakhalin Island, Russia. A recent pilot project at Piceance, Colorado, demonstrated the technical viability of this option for onshore US disposal of cuttings.
Reducing “footprint” includes reducing the amount of land needed for drilling and completion operations.
With our expertise in extended reach drilling, we can now drill multiple wells from a single pad, which has also been made smaller due to advances in engineering design. Horizontal drilling techniques also help to increase well productivity, requiring fewer wells.
In Cold Lake, the overall footprint has been reduced by 50% due to our ability to drill additional wells from an existing location. Horizontal well technology is being used to replace multiple vertical wells. The advances in pad design and well pattern also help to both maximize resource recovery and reduce the impact of our presence.
Pad design/well construction
For land locations, pads are built in such a way as to diminish the potential impact to the environment. Liners, soil cementation and other surface barriers are used to protect the shallow soils and ground water.
In Nigeria, air emissions are reduced by testing gas wells directly to sales lines in place of flaring them into the atmosphere. This significantly lowers emissions and heat output and reduces the risk of spills. In Qatar, efforts have been made to minimize flaring while maintaining parameters required for safe joint venture operations.
In cases where a rig is in place for an extended period of time, electricity from the local utility supplier can be used to power the rig and reduce diesel generator usage. This has been done in the US, Western Canada and Germany.
Our first waste management priority is to minimize its generation, then to re-use or recycle waste wherever possible. We continue to seek opportunities to reduce the environmental impacts from our operations by reducing the generation of waste.
Waste at all drilling sites is separated into major categories such as chemical, organic, inorganic and metal to be disposed of or recycled in the appropriate manner.
The Environmental and Energy Savings Initiative (EESI) is part of ExxonMobil’s ongoing commitment to increase energy efficiency and reduce our overall environmental footprint. The EESI program promotes behaviors that reduce waste and improve energy efficiency. Since the implementation at the Greenspoint facility in the USA, Styrofoam cup restocking has been reduced significantly as employees use reusable cups; additionally, paper, plastic, glass and aluminum recycling has been shown to provide significant waste reduction.
Newly-designed work gloves offer better hand protection and can be washed and reused. This has been extremely useful in reducing the amount of waste generated. Following introduction of these new technology gloves in Malaysia, conventional glove disposal dropped more than 85%.
Environmentally-friendly hydraulic fluids are used in the surface and subsea BOP control systems, top drives and iron roughnecks.
Improving the reliability of slip joint packer systems on deepwater wells
Slip joint packer systems were originally designed for use with water-based drilling fluid and typically a minor amount of fluid seepage was relied upon to lubricate the packer. When non-aqueous drilling fluids were first used, packers were operated at a higher pressure to eliminate seepage; however, this increased the potential for a seal failure. ExxonMobil now maintains standards requiring redundant packer systems and controls to ensure overall system reliability.
Non-Aqueous Fluid Packing (NAFPac) technique
ExxonMobil patented the NAFPac gravel packing completion technique which increases well productivity and reduces the number of wells needed to develop each reservoir. This method installs gravel pack screens in non-aqueous drilling fluid, eliminating formation stability problems and fluid compatibility issues. Fewer wells result in less impact to the environment.
Engineering – optimising well count
ExxonMobil’s Malaysia team of engineers optimised a process that reduced the well count by more than 20% while maintaining production volumes. The benefits to the environment include a reduction in the use of diesel fuel and water, lower air emissions and 2700 metric tons fewer drill cuttings being discharged to sea.