Skip to main content

Rehabilitating and decommissioning

Effectively decommissioning onshore and offshore assets is essential to reducing our overall environmental impact. When operations reach the end of their useful life, we work to ensure the safe and responsible decommissioning of our assets.

To do so, we develop decommissioning plans that utilize proven and cost-effective methods and consider potential risks, costs and benefits.

Since its creation in 2008, ExxonMobil Environmental Services (EMES) — our global functional organization that provides guidance and support on the remediation and stewardship of surplus sites — has managed more than USD $5.7 billion of remediation work and returned more than 1,800 properties to beneficial end uses. In 2015 alone, EMES monitored 5,700 active sites in more than 30 countries.

In 2015, we collaborated with the Land Trust Alliance, a national land conservation organization, to create Establishing Conservation Easements on Corporate Lands: A Guide for Corporations and Land Trusts. This document will serve as a reference tool for many corporations, including those in the oil and gas industry, when managing land with inherent conservation value warranting permanent protection.

Whenever possible, we look for opportunities to repurpose former ExxonMobil sites and surplus properties for beneficial use. For example, Harris County, Texas, is home to an inland waterfowl rookery, which serves as a sheltered breeding spot for herons, egrets, spoonbills and other species of coastal water birds. To help protect the rookery, we donated more than five acres of surplus land located adjacent to the rookery for stewardship by the Armand Bayou Nature Center. The former drill site now serves as a protective buffer to ensure that the rookery and its inhabitants are safe from future development.


We continually seek to enhance our reclamation processes by integrating site remediation plans into life cycle planning for an asset. Before Imperial Oil, an ExxonMobil affiliate in Canada, began construction of the Kearl development, a pre-disturbance assessment was conducted. This assessment helped to document reference conditions for the site’s soils and vegetation, which will be used to plan and execute end-of-life site reclamation work. In particular, topsoil was salvaged during the construction phase so that it could be used during reclamation.

Our focus on site rehabilitation leads us toward innovative ways to ensure the land we use is available for environmental and societal benefits in the future. For example, as areas of the Kearl oil sands mine in Canada are no longer needed, we prioritize them for progressive reclamation. Progressive reclamation not only prevents erosion in the short term, but also allows the land to be returned to the local boreal forest ecosystem more quickly. Reclamation planners at Kearl, working closely with local First Nations, aim to achieve a maintenance-free, self-sustaining landscape in the long term, the planning for which takes into account traditional knowledge of the area’s wildlife, habitat and biodiversity. As of 2015, cumulative permanent reclamation on the Kearl lease was approximately 242 acres that include terrestrial, wetland and aquatic ecosystems.

ExxonMobil is committed to the responsible, sustainable and consistent stewardship of rehabilitated former operational sites. We support science-based, cost-effective approaches to remediation that utilize consistent criteria and seek to align the interests of a broad array of stakeholders. In 2013, ExxonMobil Environmental Services Company used an organic capping approach to treat marshland and a cove impacted by the Pegasus Pipeline incident. This technique promotes the most effective cleanup with the least environmental disturbance. Some of the affected soil and sediment in the cove was targeted for removal and reactive capping was employed in the open water area using a mixture of sand and clay. This multi-dimensional risk-based approach addresses residual sheening conditions observed in isolated areas in the western part of the cove.

Up Close: Offshore decommissioning in the Gulf of Mexico

The deepwater Gulf of Mexico is one of the largest sources of oil production in the United States and will likely play a key role in meeting rising global energy demand. However, Gulf of Mexico operations present a unique set of technological, environmental and social challenges throughout the life of an asset. ExxonMobil has been safely conducting exploration and production operations in the Gulf of Mexico for more than 60 years. Technological advances have enabled ExxonMobil to produce offshore oil and gas deposits in water depths that seemed unreachable a generation ago.

While ExxonMobil uses a systematic process for decommissioning offshore assets, our site-specific approach varies depending on the type of structure and unique characteristics of a location.

In all cases, we evaluate potential strategies based on a number of factors including safety, environmental and social considerations. Certain decommissioning strategies have the potential to provide continued benefits to the environment. Accordingly, we use comparative assessments as well as ecological data to determine the best strategy.

One example of our approach to offshore decommissioning was demonstrated at a deepwater platform site offshore of Louisiana. To help understand the unique ecological environment supported by this offshore platform, ExxonMobil’s Upstream Research Company (URC) used remotely operated vehicles (ROV) to complete an ecologically focused deep sea survey. URC partnered with a Gulf of Mexico fisheries expert from Louisiana State University, Dr. Mark Benfield, who assisted in developing new detection methodologies and reviewing the ROV data.

The survey data confirmed that the platform hosts a healthy and diverse biological community, including thriving communities of Lophelia pertusa, a deepwater coral species. Lophelia pertusa is an important species because it provides habitat for other invertebrates and fish in a similar manner to shallow water coral reefs. Many other deepwater invertebrates were also identified, including squat lobsters, sea stars, anemones and crabs. A variety of deepwater fish species were also identified on or very near the structure.

  • Dr. Mark Benfield

    Professor, Louisiana State University 
    “At this offshore platform site is a large oasis of healthy cold-water coral reef in an otherwise low-diversity, soft-bottom region of the northern Gulf of Mexico. The scientific analysis completed to date supports the opportunity of reefing in place. This overall area available for cold-water corals and their associated fish and invertebrate populations has established an important habitat for large, reproductively important groupers and other deepwater fishes and an opportunity to study the expansion of a cold-water coral reef community. Maintaining this habitat will also help to eliminate a population of invasive orange cup coral and associated Indo-Pacific lionfish.”


Throughout the Upstream asset life cycle — from exploration to decommissioning — care is taken to limit disruptions to local communities and protect the environment. Accordingly, ExxonMobil ensures that decommissioning activities are planned and conducted to appropriately manage risks. For our fixed manufacturing assets, the same care is taken. For example, in 2015, we completed decommissioning a steam cracker at our Fawley refinery in the United Kingdom, the largest demolition project ExxonMobil has carried out in Europe.

As part of the project, ExxonMobil worked to preserve materials that could be reused or recycled for other purposes. In total, we segregated and recycled around 15,000 metric tons of materials, which represented 89 percent of all materials recovered from the demolition site. Ferrous and non-ferrous metals were sold as scrap and the concrete was crushed and reused for land reclamation. Material that was unable to be recycled was disposed of according to local regulations.

Additionally, the project incorporated environmental considerations. For example, some activities were rescheduled to avoid potential impact on nesting birds and annual bird migrations. The Fawley site also features a small population of wild bee orchids and particular care was taken not to damage the orchids during the flowering season.

  • Rob Tarbard

    Project manager, Fawley demolition
    “It really is the end of an era. I hope this project can stand as an example to the petrochemical industry of how the demolition of large-scale units can be achieved in a safe and controlled manner.”

loading video...

Offshore assets present unique and complex decommissioning challenges due to a combination of factors, including the specific marine ecosystem at each site and the size and weight of facilities, as well as the inherent risks of removing such facilities in marine environments. As a result, the planning and preparation for decommissioning some offshore assets can start up to 10 years prior to the actual execution. During the planning phase, we seek to incorporate lessons learned from other decommissioning projects as well as expert advice from interested parties. These parties may include fishing communities, environmental organizations and academia. We believe stakeholder engagement is critical to helping us gain public support for the facility decommissioning recommendations we submit to the government.

In recognition of the unique challenges associated with offshore assets, we created an offshore decommissioning center of expertise (COE) in 2015. This COE is tasked with planning and managing the decommissioning of our offshore assets.