Plains All American Will Appoint New COO on October 2

Houston-based pipeline operator Dean Liollio will assume the role of chief operating officer.

Updated on Sept. 29, 2026 in People

Isometric editorial illustration of a pipeline valve station with steel pipes in an open landscape, representing infrastructure operations. — Plains All American Pipeline has appointed Dean Liollio as its new chief operating officer, effective October 2, succeeding the departing Chris Chandler. AI Illustration. Upload story photo >

Plains All American Pipeline and Plains GP Holdings have appointed Dean Liollio as executive vice president and chief operating officer effective October 2, 2026. Liollio succeeds Chris Chandler, who is resigning from the position to pursue other interests.

Why it matters

The change in leadership brings a long-tenured executive into the firm's top operational role as it manages pipeline infrastructure across the U.S. and Canada. This shift follows years of stability in company management and occurs as the firm prepares to transition under new oversight.

Dean Liollio is 67 years old and has been with the organization since 2008, holding various leadership roles during his 18-year tenure. This change impacts the executive office at the Houston-based firm.

The players

Dean Liollio

A long-time executive who has held multiple leadership positions within the pipeline organization since 2008.

Chris Chandler

The outgoing executive vice president and chief operating officer who is resigning to pursue outside interests.

Plains All American Pipeline

A major Houston-based master limited partnership focused on the transport and storage of crude oil and natural gas.

The details

Liollio moves into the chief operating officer role after serving as senior vice president of special projects since June 2024. He brings extensive experience from his prior executive roles, including serving as president of Plains Midstream Canada from 2020 until 2024 and president of PAA Natural Gas Storage from 2008 until 2020. The leadership change involves a direct handoff of responsibilities between Liollio and the departing Chris Chandler.

Dean Liollio joined the company in 2008.
He served as president of Plains Midstream Canada from 2020 until 2024.
Liollio held the role of SVP of special projects from June 2024 until October 2026.
The executive appointment was publicly announced on September 29, 2026.
Dean Liollio officially begins his tenure as COO on October 2, 2026.

Market Landscape

The appointment of a veteran executive like Liollio reflects the industry trend of favoring institutional knowledge during periods of internal leadership turnover. This shift follows the pattern established by the 2024 leadership transition of Plains Midstream Canada.

Operators should monitor whether the leadership change signals a shift in midstream project priorities or infrastructure maintenance schedules starting this October. Maintain awareness of the transition as Liollio assumes oversight of company-wide logistics in early October 2026.

The takeaway

Internal promotions often serve as a signal for strategic continuity rather than radical operational change. Operators should track how the new COO's background in midstream and storage dictates capital allocation in the coming quarters.