Oil and gas
10 Occidental Petroleum engineering leaders
These ten current and former Occidental Petroleum engineering leaders have held vice president, chief facilities engineer, engineering director and head of drilling engineering roles at Oxy and its subsidiaries. A reader can learn how engineering leaders build and run their teams in oil and gas companies.
Professionals to explore
01—10Andres M. Oleas
LinkedInExperience: Head of Drilling Engineering · Occidental Petroleum of Qatar
Head of Drilling Engineering at Occidental Petroleum of Qatar since February 2019, a role the profile lists as current. The profile also lists Sr. Advisor Drilling Engineer - World Wide Drilling and Completions at Oxy since October 2019 and Head of Drilling Engineering at Oxy (2019).
Bill Geer
LinkedInExperience: Director of Corporate Engineering · Oxy
Director of Corporate Engineering at Oxy since September 2023, a role the profile places in Deer Park, Texas. Former Oxy roles include Manager of Process Engineering (2022–2023) and Principal Process Engineer (2013–2022).
Clay Thompson, P.E.
LinkedInExperience: Director, Deepwater Facilities Engineering & Construction · Oxy
Former Director, Deepwater Facilities Engineering & Construction at Oxy (2020–2021). The profile lists Director, GOM Operations at Oxy as current since October 2021, plus Marine Engineering Manager roles at Oxy (2019–2020) and Anadarko Petroleum Corporation (2012–2019).
Mark Kapelke
LinkedInExperience: Vice President - Engineering & Operations · OXY USA Inc.
Former Vice President - Engineering & Operations at OXY USA Inc. (2010–2014); the profile describes responsibility for Oxy's oil and gas operations in the Los Angeles Basin. Current title at Oxy since January 2019 is Operations Manager, and the profile also lists Operations Manager at Occidental Colombia (2014–2019).
Mark Slezak
LinkedInExperience: Director, Process Safety & Risk Engineering · Oxy
Former Director, Process Safety & Risk Engineering at Oxy, a role the profile dates from July 2015; the profile lists Retired at Oxy since April 2026. It also lists HSE Risk Manager at Oxy from March 2012 and Risk Engineering Leader at Occidental Oil & Gas (2010–2011).
Richard Fish
LinkedInExperience: Head of Drilling Engineering (DES) · Occidental Petroleum of Qatar
Former Head of Drilling Engineering (DES) at Occidental Petroleum of Qatar (2016–2025). Current title at Oxy since October 2024 is Drilling Manager Oxy Oman, and the profile also lists Drilling and completions manager at Occidental petroleum of qatar (2019–2025).
Roman Gomez
LinkedInExperience: Director of Facilities Engineering and Construction · Oxy
Director of Facilities Engineering and Construction at Oxy since January 2022, a role the profile places in Engineering and Technical at Director level. Former Oxy roles include Asset Facility Manager (2020–2021) and Head of Major Projects (2016–2019).
Rusty Hanna
LinkedInExperience: Director of Production Engineering - US Offshore · Oxy
Director of Production Engineering - US Offshore at Oxy since June 2020; the profile describes the role as Production Engineering Director for GOM Assets. Former Oxy roles include Asset Manager (2018–2020) and Production Engineering Manager (2015–2016).
Tim Rollenhagen, P.E.
LinkedInExperience: Director Engineering Services · Oxy
Former Director Engineering Services at Oxy (2023–2024). Current title at Oxy since April 2025 is Principal and Chief Facilities Engineer, and the profile also lists Chief - Facilities Engineering at Oxy (2024–2025) and Director, Technical Services at Western Midstream (2023).
Tom Rees
LinkedInExperience: Chief Facilities Engineer · Oxy
Chief Facilities Engineer at Oxy, a current role the profile dates from January 2009 and places in Engineering and Technical at C-Level. The profile also lists VP Major Projects at Occidental Oil & Gas Corporation as current since January 2009.
Choose the right perspective
Match the person to the engineering discipline behind your question, since facilities, production, drilling and process safety engineering are run by different teams. Check whether the relevant Oxy role is current or former before asking how engineering works there today.
Questions to take into the conversation
- 01How does an exploration and production company split engineering work between corporate teams and individual assets?
- 02How do facilities engineering leaders plan and review construction work on new oil and gas developments?
- 03What does a supplier need to show before engineering teams at Oxy approve new equipment or services?
Reaching Occidental Petroleum engineering leaders
How can I contact one of these Occidental Petroleum engineering leaders?
Pick one of the 10 people on this page and choose "Book a paid call", or describe your project to find others. You offer a fee for a 15-minute call or a written answer, Instant Expert finds the person's work email and sends the invitation, and they decide whether to accept. The list covers 3 companies: Occidental Petroleum of Qatar, Oxy and OXY USA Inc., based on profile data retrieved on October 5, 2026. Being listed here doesn't mean someone has agreed to take calls.
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About this directory
This is a professional research starting point based on business profile data retrieved on . Titles and companies reflect that source snapshot and may describe past or present roles. Check the linked profiles for current details. Inclusion does not imply Instant Expert membership or availability.
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