Intern/Co-op - Refining Chemical Engineering Fall 2026

At MPC, we’re committed to being a great place to work – one that welcomes new ideas, encourages diverse perspectives, develops our people, and fosters a collaborative team environment.

Responsibilities

As a Chemical Engineer at a Marathon refinery, you can expect to:

• Become familiar with process equipment fundamentals and best practices
• Build critical thinking skills
• Gain an understanding of how all engineering disciplines work together as a cohesive team
• Gain knowledge of various aspects of a refinery by working with a team of professionals who run a specific portion of the refining process
• Work on more than one area of the refinery, leading to a broad understanding of how the plant operates
• Expand your written and verbal presentation skills in a professional work environment

Most Chemical Engineering co-ops and interns enter into the following positions:

Process / Technical Service Engineers

• Work on a variety of projects in the Technical Services Department with your mentor, applying classroom experience as a Chemical Engineer
• Develop and lead test runs to optimize refinery operations
• Perform process engineering calculations concerning various process technology or equipment in the refinery
• Monitor and make recommendations regarding catalyst and adsorbents
• Complete projects and provide recommendations for improvements to the refinery process and equipment

Operations Research Engineers

• Help develop planning, blending, scheduling, and process models for refinery engineers
• Validate production data and mass balancing
• Perform process modeling
• Develop graphical interfaces of refinery process units

Environmental Engineers

• Work on projects involving compliance of the entire refinery, gaining exposure to most process units
• Apply engineering principles and calculations to various environmental projects
• Gain broad knowledge of environmental laws applicable to refineries and compliance requirements
• Perform process calculations for the Risk Management Plan, including physical surveys of refinery process units
• Work on process engineering projects within a Wastewater Treatment Plant
• Participate in inspections and/or testing conducted by federal, state, or local officials

Products Control / Economics Engineers

• Work on projects including operations, blending, and refinery economics
• Gain an understanding of tank farm operations and product preparation/shipping
• Analyze refinery process flow data and compare to recommended optimum levels to identify equipment failures
• Update information on gasoline blends and tank samples for annual blender waiver audits
• Develop applications to better present process data for refinery operating decisions

Requirements

• Majoring in Chemical Engineering
• Strong academic performance
• Authorized to work in the US on a full-time indefinite basis without employment visa sponsorship now or in the future
• Availability for spring, summer, and fall semesters; multiple work terms preferred
• Valid driver’s license
• Concurrent enrollment in a degree-seeking program
• Military experience a plus

Pay

$32.92 – $41.60 per hour

Benefits

• Health, vision, and dental insurance
• Paid time off
• 401k matching program
• Paid parental leave
• Educational reimbursement
• Discretionary company-sponsored annual bonus program

Schedule

Part-time (Intern)

Locations: Findlay, Ohio; Anacortes, Washington; Canonsburg, Pennsylvania; Canton, Ohio; Catlettsburg, Kentucky; Detroit, Michigan; Dickinson, North Dakota; El Paso, Texas; Garyville, Louisiana; Kenai, Alaska; Mandan, North Dakota; Martinez, California; Owensboro, Kentucky; Robinson, Illinois; Salt Lake City, Utah; San Antonio, Texas; St Paul Park, Minnesota; Texas City, Texas; Wilmington, California