Associates

James Ahrens

Senior Associate

James Ahrens is an economics and planning professional with over 36 years of experience in optimizing petroleum refinery operations and the associated supply/distribution logistics.

John Askounis

Senior Associate

John has over 40 years of downstream oil experience with deep expertise in refining, economics, and fuels policy, including leadership roles at Texaco, Tosco, ConocoPhillips, and Phillips 66.

Dr. Allison Bergquist

Senior Associate

Dr. Allison Bergquist has a broad range of experiences that span government, national security, oil and gas, and the environment. She is the founder and owner of River Basin, LLC, which specializes in energy security strategy.

Hugo Boiten, MSc.

Senior Associate

Hugo is a veteran of the sustainable aviation fuel (SAF) and renewable fuels industry, bringing over 17 years of experience in product strategy and leadership. He specializes in bridging the gap between complex research and development (R&D), regulation and scalable commercial products, with a career-long focus on driving the global green transition through strategic governance and business model innovation.

Dr. Simoon Cannon

Senior Associate

Simoon is an entrepreneur, chemical engineer, publisher and logistics expert with more than 20 years of experience. She has led projects in artificial intelligence and "big data" in fuel automation and inventory management for the oil, gas, and aviation industries

Thomas Daniels

Thomas Daniels' 35-year career is comprised of 15 years consulting to the energy industry and 20 years of operations, business development, and strategic planning in the refining and power generation sector.

Nick Griffith

Senior Associate

Nick Griffith has an extensive maritime background which includes work on numerous ocean-going towing and salvage tugs, oil tankers of most types, training, passenger, and RORO vessels.

Vaughn Hulleman

Senior Associate

Vaughn Hulleman has more than 30 years of experience helping organizations across the oil industry value chain address strategic challenges and strengthen operational capabilities.

Jeff Kennedy

Senior Associate

Jeff Kennedy spent more than 18 years with Mobil Oil. An inspirational leader, visionary strategist, and fearless catalyst of change, Jeff sees the end game that others don't.

Michael Leister

Senior Associate

Michael Leister spent more than 35 years with Marathon Oil Company and then Marathon Petroleum Company. He has been an industry leader in dealing with clean fuels regulations and legislation.

Chuck LeTavec

Senior Associate

Chuck brings more than three decades of downstream experience across refining, logistics, supply, and renewable fuels strategy, including key leadership roles focused on project evaluation, optimization, and regulatory strategy.

Eric Lingman

Senior Associate

Eric Lingman is a seasoned refining expert with 40+ years of experience in clean‑fuels innovation, refinery optimization, and strategic leadership across the global energy sector.

Paul Machiele

Senior Associate

Paul is a seasoned fuel‑policy and transportation‑emissions expert with nearly four decades of experience at EPA and across federal, state, and local agencies.

James L. Mladenik

Senior Associate

After 33 years with ARCO and BP, Jim Mladenik joined Stillwater Associates in January 2016. Recent projects have included consultation on mergers, litigation support, and comments to the EPA on the role of E85 in meeting the Renewable Fuel Standard.

Michael Myers

Senior Associate

Michael's executive experience covers full profit and loss responsibilities for a large fleet of tank vessels, operating expenditure, capital expenditure, and revenue budget management, safety management system oversight, marketing, business development, and contracts management.

Leigh Noda

Senior Associate

Leigh Noda has a very broad based experience in the petroleum refining, petroleum products and alternate fuels arenas.

Rick Penfield

Senior Associate

With over thirty-five years’ combined experience at ExxonMobil, its affiliated and predecessor companies, and as a consultant, Rick brings extensive leadership, supply chain planning and analytical knowledge to his clients.

James Primrose

Senior Associate

James Primrose is a leader in the low carbon energy space with more that 20 years’ experience. Currently he is CEO and founder of JRK Primrose Consulting Ltd helping companies build low carbon fuels businesses at scale.

Dr. Michael Rensing

Dr. Michael Rensing was part of the British Columbia public service for 20 years. As Executive Director of the Low Carbon Fuels Branch, Electricity and Alternative Energy Division at the BC Ministry of Energy, Mines, and Low Carbon Innovation, he led the development of BC’s Low Carbon Fuel Standard Program. This program has been responsible...

Mark Rigby

Senior Associate

Mark Rigby has extensive experience within the energy and environmental sectors leading business development and finance functions.

Gordon Schremp

Senior Associate

Gordon Schremp recently concluded a 32-year career working for the California Energy Commission. During his time at the Energy Commission, he developed expertise in a variety of transportation energy topics.

Arshad Sheikh

Senior Associate

Arshad has 41 years of experience working for British Petroleum and Plains All American Pipeline, where he was a team leader in crude oil logistics, distribution, and trading as well as commercial negotiations and project management.

Dr. Adam Schubert

Senior Associate

Adam joined Stillwater in 2018 following a 33-year career with ARCO, BP, and Butamax (a joint venture of BP and DuPont).

David Wilshin

General Counsel

David Wilshin has been an attorney for more than four decades and General Counsel for Stillwater Associates since the early days of the company in the late 1990s.

Gary Yowell

Senior Associate

Gary Yowell spent more than thirty years with the California Energy Commission (CEC), including two years with the California Air Resources Board (CARB).