Bruce Fleming has a useful qualification for the business of making the future: he knows his way around the past. Before running Montana Renewables, he spent decades inside the petroleum industry, moving through operations, business development and acquisitions. Now his company makes renewable fuels in Great Falls, Montana, at a site shared with a conventional refinery. The old equipment has acquired a second career. Fleming, a chemical engineer with a Princeton doctorate, has been helping arrange the introduction.
His proposition has the appeal of a good renovation. A refinery already has land, infrastructure and people who understand complicated industrial processes. Some of those assets can serve a different set of ingredients. The hard part is deciding what to keep, what to change and how to pay for the work. Fleming’s career has taken him through each of those questions, in countries and companies far removed from the Montana prairie.
A chemist before the conference calls
His education began with chemical engineering at the University of Delaware, followed by doctoral work at Princeton. He studied at Delaware from 1974 to 1977 and Princeton from 1977 to 1981. His thesis concerned silica polymerization. Long before the airline conversations, he was concerned with the behavior of very small things.
A 1986 paper he authored carries the wonderfully unhurried title “Kinetics of reaction between silicic acid and amorphous silica surfaces in NaCl solutions.” It appeared in the Journal of Colloid and Interface Science. For anyone who has encountered Fleming chiefly discussing gallons, project economics or agricultural markets, the publication offers a glimpse of the technical foundation beneath the executive vocabulary. The molecules arrived before the mergers.
Amoco occupied the first long stretch of his industrial career, from 1981 through 1996. His assignments covered operations, planning and business development, culminating in vice president of China business development. He then became managing director of Hong Kong-based Orient Refining, serving from 1997 through 2004. He was a founder of that business as well.
In 2004 he joined Tesoro, where he became vice president of mergers and acquisitions and an officer of Tesoro Companies. Calumet brought him in during March 2016 as executive vice president of strategy and growth. By February 2021, his remit included Montana Renewables and corporate development. He also sits on the Board of M&A Standards, an organization concerned with accreditation and testing for the dealmaking profession.
The equipment was already there
The starting point in Great Falls was unusually tangible: an idle catalytic feed hydrotreater. The 24,000-barrel-per-day unit could be redirected toward renewable feedstocks, with technology from Topsoe. The plan required rearranging the refinery and selecting technology with an operating history. An existing industrial site still needs serious engineering; familiarity is useful chiefly because it helps identify the risks.
The original journey from concept to implementation took 18 months. Fleming offered a dry comparison. There is a recognizable executive impatience in the remark, but also a preference for equipment that has already demonstrated what it can do.
“Most people take 18 months to do the initial study before they actually do any of the work.”Bruce Fleming
The value of a conversion depends on understanding the equipment well enough to change its assignment.
Commercial operations began in late 2022. The renewable business had been separated legally and commercially from Calumet in November 2021 and designated an unrestricted subsidiary. Its Great Falls location gave it access to refining assets, rail connections and western markets. Those are fairly earthbound advantages for a business associated with flying. They also help explain why this particular patch of Montana became part of Fleming’s next chapter.
First, find somebody who will buy it
By May 2023, Montana Renewables was celebrating initial sustainable aviation fuel shipments under a multiyear agreement with Shell Trading. The gathering brought aviation customers and Montana Governor Greg Gianforte to Great Falls. Shell’s distribution role connected the production site with airline customers including Delta, Alaska and JetBlue. A renewable fuel business needs that commercial bridge as surely as it needs a working reactor.
Fleming described Shell as a logical partner for reaching multiple airlines and airports. The arrangement placed Montana’s output inside a much wider delivery system. That distinction matters to his story: the CEO’s job extends beyond the refinery gate. Making a fuel, finding its buyer and getting it into the aviation supply chain are separate accomplishments, each capable of obstructing the others.
A February 2026 agreement with World Energy widened the commercial network again. The companies announced plans to deliver more than 70 million gallons of SAF over three years. World Energy brought its corporate aviation decarbonization business and experience in environmental attributes to the relationship. Fleming linked the deal to demand for the fuel and to Montana agriculture. The contracts give his industrial argument a practical test: somebody has agreed to take the product.
Five railcars and a much bigger idea
In September 2023, the company received its first five railcars of camelina oil. A ceremony on September 18 marked the addition of the crop to a feedstock list already including canola oil, corn oil and tallow. For Fleming, camelina supplied a particularly local way to explain a business otherwise crowded with unfamiliar acronyms.
Camelina is an oilseed crop, and Fleming has emphasized its nonfood character and its potential value to regional growers. He described a broader ambition at the arrival celebration: attracting seed-crushing and meat-packing facilities to Montana. The argument runs along the supply chain. A fuel producer buys agricultural materials; processors prepare those materials; farmers and ranchers supply them. More of that activity could take place nearby.
The connection became concrete again in September 2024, when Montana Renewables announced it had shipped the first SAF blend for Minneapolis-St. Paul International Airport. The renewable fuel had been produced from Minnesota camelina. Fleming pointed to the shorter local supply chain and the crop’s additional earning potential for farmers. Here was an itinerary with an agricultural first leg: a Minnesota crop, a Montana plant, a Minnesota airport.
Camelina oil→Great Falls
Fuel production→MSP airport
SAF blend
The inconvenient business of water
Running the plant also brought Fleming into less celebratory rooms. In January 2024, Pondera County residents questioned a proposal to dispose of the company’s wastewater in old oil and gas wells. Fleming traveled from Indianapolis to a county commission meeting. Residents raised concerns about groundwater, rural truck traffic and the composition of the wastewater. Industrial projects have neighbors, and neighbors have questions that survive a ribbon-cutting.
The water came from washing feedstocks before fuel production. The company had been sending it to out-of-state disposal facilities. Fleming argued for a closer solution, while local residents sought assurances about the proposed injection wells. The disagreement put the daily consequences of a renewable fuels operation in public view. A plant’s environmental claims and its local obligations have to be considered together.
In July 2025, Montana Renewables announced plans for an on-site treatment facility. The proposed system would process agricultural wash water locally and recover additional oil. Fleming’s explanation focused on the expense of paying railroads to move water and other operators to handle disposal. As a business problem, the water had all the ingredients he regularly discusses: transportation, processing capacity, operating cost and the question of what should happen in Montana.
A smaller construction bill changes the plot
The expansion story changed materially in September 2026. Calumet revised MaxSAF into six smaller projects built around reusing installed equipment from the adjacent refinery. The company set a target of approximately 200 million gallons of annual SAF production by the end of 2028. It put remaining project capital at $137 million, compared with the $1.2 billion contemplated for the original Phase 2 plan.
The revised approach again turns on what is already available. A hydrotreater, hydrogen plant and naphtha splitter would be redeployed under a long-term lease. The financing plan combined retained earnings with a final $34 million Department of Energy loan draw, subject to conditions. The company said the adjacent operation would continue retail asphalt production and retain its employees.
The operating figure and the ambition deserve separate places on the page. In September, the reported SAF production run rate was 60 million gallons per year. The 200 million figure remained a target for 2028. Fleming leads a business that has moved beyond an initial demonstration, while still having substantial work ahead. The successive plans also show how an industrial strategy changes as engineers learn more about the equipment and executives reconsider the bill.
Annualized production rate, not total annual deliveries. The later figure is a projection.
The pizza-place economics of it all
For someone whose career includes Beijing, Hong Kong and the acquisitions business, Fleming can make a pointedly ordinary case for economic development. Asked about Great Falls, he described participating in the local economy: “I go down to the pizza place that I like. We shop at Albertsons. We fuel our vehicles.” The description gives the big investment numbers a human scale. Employees and visiting executives buy dinner and groceries, too.
His public manner often follows that movement from the technical to the familiar. A discussion of refinery conversion can become a discussion of a farmer’s next customer. A water-treatment project becomes a question about paying to transport water across the country. The explanations keep returning to the physical business: where the ingredients originate, what the machinery does and how far the product must travel.
That is the thread connecting the engineer, the acquisitions executive and the renewable fuels CEO. Fleming has spent a career working with industrial assets and their possible uses. In Great Falls, those possibilities include a new buyer for an oilseed crop and another assignment for equipment that already exists. His next chapter will be measured in operating results. For now, the machinery has more work to do.