Arden Ahnell
Arden Ahnell
Senior Managing Scientist
Environmental & Earth Sciences

Mr. Ahnell has more than 40 years of experience with health, safety, and environmental operations and policy. He has a wide range of experience including oil spill management/ crisis management, soil and groundwater remediation, product stewardship, environmental technology and corporate environmental policy. He is particularly expert on offshore oil spill response strategies including chemical dispersant use and effects, including subsea applications.. His recent consulting work has focused on offshore dispersant use for oil spill response around the world.

His clients have been primarily trade organizations such as IPIECA, OGP, and API, where he has developed dispersant guidance, and research reports. This work included advisory consulting and preparation of technical comments on recent U.S. oil spill regulations.

With 32 years of prior work experience with BP both in the U.S. and abroad, Mr. Ahnell has extensive experience with environmental monitoring and treatment technology. He recently served in BP Upstream as Director, Environmental Technology, and as Deputy Director for BP’s Gulf Coast Restoration Organization, directing the science effort to support the response and understand the science of a deep sea oil release during and following the Deepwater Horizon incident. His previous roles at BP include Director of Product Stewardship, providing policy, product regulatory and product safety communication expertise, and support across the BP Group. He has also held various leadership roles involving contaminated land cleanup management, corporate policy, technology, and operations support nationally and internationally. As U.S. External Affairs Director, he was involved with BP’s climate change efforts.

Mr. Ahnell’s knowledge and skill set includes:

  • In-depth knowledge of dispersant use and effects, especially subsea dispersant use 
  • In-depth knowledge of ocean oil spill impacts
  • Expertise in environmental technology for application in the upstream oil and gas industry
  • Oil spill and crisis management expertise/experience obtained in the Deepwater Horizon incident 
  • Strong technology, team management, and performance improvement background 
  • Strong interest and track record in finding HSE strategies that work in business
  • Experienced operations and health, safety and environment manager
  • Broad knowledge of petroleum business and HSE activities, including two expatriate assignments
  • In-depth knowledge of HSE regulatory processes and issues, along with audit experience Liability management and HSE acquisition/divestiture negotiation expertise.


  • M.S., Environmental Engineering, University of Illinois, Chicago, 1989
  • B.S., Biochemistry, University of Illinois, Chicago, 1982


Ahnell AD. Dispersant and In-Situ Burning Workshop for Angolan Government and Petroleum Industry, sponsored by the Angola Association of Exploration and Production, Luanda, Angola, 2014.

Ahnell AD. Government Industry Workshop on Oil Spill Response Strategies for the Caspian Sea sponsored by BP, Baku, Azerbaijan, 2013.

Ahnell AD. Dispersant Application During Deepwater Horizon Spill Presentation for Trinidad and Tobago Government sponsored by BP, Port of Spain, Trinidad, 2013.

Ahnell AD. Workshop on Deepwater Response Capabilities for Petrobras sponsored by BP, Rio de Janeiro, Brazil, 2012.

Ahnell AD. Workshop Addressing Oil Spill Dispersant Use sponsored by the European Maritime Safety Agency, Lisbon, Portugal, 2012.

Dispersant Workshop for Egyptian Government and Petroleum Industry sponsored by BP, Cairo, Egypt, 2012. 

Ahnell AD. Gulf of Mexico Science and Technology, Presentation at Harvard University, Boston, MA, 2011. 

Ahnell AD. Gulf of Mexico Science and Technology, Presentation at Tufts University, Boston, MA, 2011. 

Ahnell AD. Dispersants Evaluation, Use and Environmental Concentrations during the DWH Incident, Presentation at Society of Environmental Toxicologists and Chemists Annual Meeting, Boston, MA, 2011. 

Prior Experience

Project Manager, Marine Division, HDR, 2015

Director, Environmental Technology and Knowledge Management, Upstream, BP, 2012–2014

Deputy NRDA Director—Gulf Coast Restoration, BP, 2010–2012

Director, Global Product Stewardship, BP, 2008–2010

Strategy and Planning Manager—Remediation Management, BP, 2004–2008

Retail Portfolio Manager—Remediation Management, BP, 2001–2003

Team Leader, Management Systems and Assurance, BP, 2000

Manager, Health, Safety and Environment—External Affairs, BP, 1997–1999

Manager, Health, Safety and Environment Shared Resource, BP, 1993–1997

Manager, HSE Technology Policy, BP 1992–1993

Manager, Environmental Technology Research Division, BP, 1990–1991

Senior Engineer to Deputy Manager—Environmental Technology Research Division, BP, 1982–1990

Environmental Chemist, Illinois Environmental Protection Agency, 1975–1982

Professional Affiliations

Society of Petroleum Engineers

American Chemical Society

Society of Environmental Toxicologists and Chemists

Project Experience

Consulted after retirement from BP, with a focus on offshore dispersant use. Clients were primarily trade organizations such as IPIECA, OGP, and API. Developed dispersant guidance, advocacy, and research reports, including industry comments on recent U.S. oil spill regulations proposed by EPA and advising on API’s large sub-sea dispersant research effort. These assignments built on deep experience and understanding of sub-sea dispersant use during underwater oil releases such as was encountered during the Deepwater Horizon Incident.

As a direct report to the Upstream VP for Environment and a small team, managed a $6M technology program in support of upstream environment needs such as sound and marine life, air, water, biodiversity, and others, as well as planning and budgeting for the VP. Also managed the upstream global environmental discipline capability and staff development programs covering the first ten years for several hundred upstream environmental staff. Actively promoted learning in the BP upstream environmental community through information management and events across the calendar on key topics of interest. Personal technical efforts were conducted as the BP expert on the use of dispersants during an oil spill, with an emphasis on understanding subsea dispersant application in the event of an offshore underwater release. Also led various dispersant industry research and advocacy efforts worldwide.

Served as BP’s on-scene science advisor during the Deepwater Horizon incident. Afterward, managed science and natural resource damage assessment (NRDA) litigation support programs, charged with understanding many key aspects of the spill’s environmental impact. This involved a program of research and legal support concerned with oil spill transport, fate, and effects. This spill led to the largest spill science effort ever undertaken, with many new dimensions such as deep-sea spill response and potential deep-sea resources.

As Director, Global Product Stewardship, led an international team of 35 product regulatory experts delivering support worldwide in the areas of safety data communication and product regulation. Additionally, led the product stewardship discipline for the BP Group, melding policy and direction. The group provided 40,000 safety data sheets/year and successfully led the BP compliance efforts on REACH, the EU’s then-new product safety regulation, as well many other efforts. Worked closely with BP businesses to ensure compliance, improve efficiency, and enable differentiated products. Beyond meeting demanding product regulatory deadlines, identified and managed product stewardship enterprise risks and implemented a process improvement program that improved efficiency by 20%.

In 2007 and 2008, improved BP’s Remediation Management (RM) function through a process and system redesign of $250M/year in remediation spending. This far-reaching project was implemented in 2009 and provided significant improvements in project management and financial process with a two-year payback.

As an operations manager in RM, responsible for environmental liability management for all active and divested U.S. retail sites. This included liability management for 3500 active projects, with an annual budget of $130 million and a contractor workforce of over 400 across the U.S. Three heritage company teams were harmonized into one national unit, with a staff of 45 collocated with the retail business. Accomplishments included improved safety, consolidation of the supplier firms from twenty to seven, with significant simplification and savings, and transition to an Internet based financial and project information system that allowed easy access to information while automating work authorization and payment processes.

As BP’s Climate Change Manager in the U.S., represented BP at the International Climate Change Partnership, President’s Council on Sustainable Development, and in projects with NGOs such as the World Resources Institute. International activities included organizing participation in the first China Environmental Forum in Beijing and representation on a USAID speaking tour of Brazil. BP’s voluntary reporting of greenhouse gas emissions won USEPA Awards for developing best practice and delivering emission reductions.

While on assignment in the UK, led a business support team of 40+ HSE specialists providing services worldwide with a focus on high-value support. In a time of stringent cost management, the idea of a shared service acting across BP's business stream environment was successfully pioneered by refocusing selected members from corporate policy and technology groups. Personally led the activity on acquisition and divestiture within the Resource. Successfully defended against a challenge by a JV partner for over $50M in liability cost. With only general supervision, post-closure HSE claims associated with $1B worth of divestment deals were reduced from $90M to $22M.



  • M.S., Environmental Engineering, University of Illinois, Chicago, 1989
  • B.S., Biochemistry, University of Illinois, Chicago, 1982