By Lee Buchsbaum

Nestled against the tallest mountains in North America and only 10 miles from the entrance to Alaska’s Denali National Park, Emil Usibelli began mining coal in 1943. Almost 70 years later, the Usibelli coal mine (UCM) remains a thriving, expanding family owned operation. Emil’s son, Joe Usibelli Sr., took over mining operations in 1964, and today, is UCM’s chairman. His son, Joe Usibelli Jr., serves as the company’s president.

During those seven decades, the operation has grown from a small 10,000 ton per year (tpy) producer to a medium-sized 1.8-million-tpy mine. The operation employs 125 miners and it’s setting its sights on becoming a global supplier of ultra-low sulfur Alaskan sub-bituminous coal. With coal demand rising worldwide, and the export market growing, Usibelli is preparing to ramp up production from a massive set of reserves it recently acquired.

With a dragline and a truck-shovel fleet, Usibelli supplied coal powers more than 10% of Alaska’s total power grid. UCM ships coal to six Alaskan power plants, including the Golden Valley Electric Association’s 25-megawatt (mw) mine mouth power plant, the Fairbanks’ electric cooperative, Aurora Energy, and the University of Alaska Fairbanks, and three power plants at critical military bases: Fort Wainwright (U.S. Army), Eielson Air Force Base and Clear Air Force Station.

Since 1984, UCM has also been exporting increasing amounts of coal to Pacific Rim customers in Asia and South America through the year-round ice-free Seward Coal Terminal at the Port of Seward. For more than 25 years, UCM has been shipping between 400,000 tpy and 750,000 tpy to South Korea. Additionally, UCM has provided test shipments to Taiwan and Japan. Since 2004, UCM has also been sending coal to power plants in Chile. Having an outlet to the ocean is vital for Usibelli. “Not only is the export market virtually half of what the mine sells into, but the Port of Seward is the mine’s growth gateway to the future,” said Steve Denton, UCM’s vice president of business development.

Mining UCM’s Ultra-Low Sulfur Coal
While the calorfic value for Usibelli’s coal averages 7,650 Btu/lb, what sets it apart from other coals is its ultra-low sulfur content—approximately 0.2%—ranking it among the lowest sulfur coals worldwide. UCM extracts coal from three seams, each with an average thickness of 20 ft to 40 ft. Generally, up to 100 ft of unconsolidated sandstone overburden must be moved to uncover the top No. 6 seam. Another 120 ft of interburden must be moved to uncover the No. 4 seam while roughly another 80 ft of interburden must be removed to uncover the No. 3 seam, reaching nearly 400 ft at its deepest point. In some areas, UCM uses cast blasting to help remove the overburden.

UCM currently mines from several separate mines, with most current production coming from Two Bull Ridge. Coal there is mined from the Suntrana Formation at a stripping ratio of 4 to 6 cubic yards (cu yd) of overburden per ton of coal. Typical thickness of the No. 3 seam is 18 ft; No. 4 seam is 32 ft; and the No. 6 seam is 21 ft.

Once extracted, UCM’s coal is trucked to a 65-ft deep cone-shaped hopper at the east tipple where it is dumped. Two crushers underneath the hopper crush up to 1,000 tph. From there, the undersized coal passes through a tube, known as the cam span, an elevated enclosed conveyor belt that takes the coal from the east side of the Nenana River across to its western bank. Once on the west side of the river, the coal is then deposited into a large A-frame building, referred to as the west tipple. This large A-frame structure can store approximately 6,000 tons of coal and is positioned on top of a 50-ft deep gravel pad foundation. The gravel pad has a tunnel through the center for rail access. Coal is gravity-fed that runs into the railcars while the train passes slowly through the tunnel at approx-imately 0.5 mph.

Mining several different seams requires UCM to do a lot of customer specific blending at the hopper from the live stockpile adjacent to the hopper. “Depending on which customer we’re mining for, we have some pretty tight ash and Btu specs,” said Alan Renshaw, vice president engineering, UCM.

Sometimes they are able to blend through “direct” blending, meaning all of the trucks dump straight into the tipple’s cone. “We might have three trucks from two pits hauling at the same time,” said Renshaw. “We keep them paced so that we’re blending higher Btu product with lower ash product. Sometimes we also blend with a front-end loader from the live stockpile. It’s all customer specific. Our coal quality is relatively similar. But our coal may range from 7,300 to 8,400 Btu/lb. So we do all we can to maintain consistency.”

UCM’s Ace-in-the-Hole
Named by local school children as the “Ace-in-the-Hole,” UCM’s Bucyrus Erie 1300W walking dragline is the largest land mobile machine in Alaska. Purchased in 1977, it was shipped to Alaska on 26 railcars and 40 trucks, and took 11 months to re-assemble. With its 225-ft mast and 325-ft boom, the buckets used on the dragline will hold either 33, 35, or 42 cu yd of material, depending on which of the three buckets is employed. Each bucket is used for approximately 45 days and then rotated out, with the most recently used one going to the shop for maintenance and repair.

Since the dragline went into operation in November 1978, the Ace-in-the-Hole has moved more than 145 million cu yd of dirt and exposed more than 30 million tons of coal. At the end of 2002, the dragline walked from the Poker Flats mine (now being reclaimed) to the Two Bull Ridge mine. UCM’s plan calls for more than 40 million tons of coal to be mined from Two Bull Ridge over the next 25 to 30 years.

While the dragline is the primary tool for moving overburden, additional excavators are employed as needed. Several O&K hydraulic excavators, including an RH120C backhoe and an RH170 front shovel, are used to load coal and to strip overburden in areas that are too difficult for the dragline to maneuver into or too deep for the dragline to handle by itself. The backhoe has a 16-cu-yd bucket and is powered by twin 567-hp diesel engines. A large hydraulic shovel, the O&K RH-170, was added to UCM’s fleet in August 1997. Its shovel has a 26-cu-yard bucket and can load the 150-ton trucks in four passes.

A fleet of six trucks is then used to haul coal and overburden from the pit to the hopper. Beginning in 1995, several Caterpillar 785B and 785C haul trucks have been added to the fleet. These trucks have a capacity of 150 tons, more than 50% greater than the 95-ton Dresser HaulPaks they are replacing. Local modifications were made to the trucks after delivery from the manufacturer. UCM customized its beds by adding an additional 16 inches of height and 2 ft of width, allowing a larger volume of coal (which is lighter than overburden) to be hauled. Also, the engine exhaust on the trucks is modified at the factory to run through the truck bed. This keeps the metal surface heated during winter.

Many other pieces of support equipment are also needed to conduct day-to-day activities. UCM uses a variety of dozers including a Komatsu 475A-5 dozer and several Cat dozers, including the D11R-CD for these daily activities. Two road graders operate during day and night shifts to keep the haul roads smooth for the larger trucks and two water trucks provide dust control for the roads. Additionally, a high-pressure nozzle mounted on the water trucks serves as ready reaction equipment for fighting fires.

UCM’s Family of Employees
At the heart of every successful operation is a good crew. One of the most sought after jobs in the area, approximately 31% of the workforce is second, third or fourth generation Usibelli employees—adding to the familial community. With two nine-hour shifts per day, working five days a week, UCM generally does most of their actual coal mining—as opposed to overburden removal—in the daylight hours. In the dark, coal seams that are harder to mine in daylight, become really tough to get to. “Coal is black,” Renshaw said. “To see it better, we take advantage of all the light we get. We do most of our heavy stripping at night, lit up with lots of light plants all around.” In this part of the world, it can be dark during most of the winter days.

Like many operations, finding experienced operations personnel is a constant staffing challenge. “Sometimes we have difficulty finding qualified equipment operators, electricians, mechanics, welders, the works,” said Keith Walters, general manager and vice president, UCM. If they can handle the extreme weather, they generally stay and the Usibelli’s family atmosphere helps make it a great place to work. Retention is rarely an issue. Walters is a prime example. After earning a mine engineering degree, he has worked at Usibelli since 1979 starting as a junior engineer, and moving his way up to general manager and now vice president.

With such rapidly changing extreme conditions, employee safety at UCM is a prime concern. Recently Usibelli worked for more than two years without a lost time accident (LTA) and they currently stand at more than 200 days since their last incident which was a back sprain suffered while shoveling snow. “That may be a minor incident, but we take safety very seriously,” Renshaw said. “We have weekly safety meetings with our crews and every October we remind folks about winter conditions. It’s around then that things start getting icy. We ask them to slow down and concentrate as after a summer of driving, October becomes a transitional month and transitions can be dangerous.”

Renshaw, like so many of Usibelli’s workers, is a third generation miner, his grandfather moving to Alaska to work in the gold mines in the 1920s. His father, who developed the family’s still operating gold mine, was also a mining and engineering consultant, often to Usibelli. “As a kid, it was my dream to work here,” Renshaw said. “Now I’m part of the team that’s helping take this mine to a higher level.”

Dealing with -40º Highs
Mining operations at UCM continue virtually uninterrupted during all weather conditions for the entire year. Heavy snowfall, Artic cold and shortened daylight hours during the challenging winters do not generally impede progress at the mine. Ironically, that’s often when UCM ratchets up production. “With the solid freeze, winter roads are beautiful,” said Renshaw. “Any soft spots freeze solid into a wonderful pavement.”

As the temperatures dip way below freezing, keeping equipment running is the most difficult part. “We have electric engine heaters on all mobile equipment. We also have generators on the excavators and drills, and we have plenty of portable generators to plug equipment into in remote areas. We do not shut down unless it is -45ºF for more than two days in a row,” said Walters.

In fact, it’s often during the winter months that UCM’s domestic customers’ demands are greatest. And since there are few passenger trains on the Alaska Railroad, the railroad can turn trains faster during the winter.

Fierce winter storms can also frequently isolate the mine from much of the outside world too. For that reason UCM relies on its well-stocked shop and resourceful technicians to help keep things running all year long. Self-sufficiency is key and many items are fabricated on site. UCM’s shop includes a separate machine, electrical, unit repair, and glass shop, as well as a welding bay.

Expanding Markets, Expanding Reserves
In late June 2009, UCM formally announced that it had expanded its reserves to more than 700 million tons after conducting a property wide reassessment of all available geologic data on its leases. The study identified a surface mineable reserve base of approximately 700 million tons, of which, 450 million tons is classified as proven and 250 million as probable. On-going exploration work and analysis is expected to increase the total figure to nearly 1 billion tons.

All of UCM’s reserves are classified as sub-bituminous C rank coal. Typical as-mined analysis is 7,650 Btu/lb (4,250 kcal/kg), 28% moisture, 9% ash and 0.2% sulfur. In addition to very low sulfur content, coal from the area is also low in mercury and other trace elements of concern, making it one of the cleanest burning coals in the world.

Driving the need for more production is UCM’s increasing market share of exported coal. Though UCM supplies coal to all of Alaska’s coal fired power plants, there’s a ceiling to what they can take. So most of their growth opportunities will come from increasing exports. This year UCM hopes to ship up to 900,000 tons through the coal terminal at the Port of Seward, located on beautiful Resurrection Bay. Perhaps the northern most ice-free year round harbor in the world, Seward was the original port for the state-owned Alaska railroad. Though still owned by the railroad, the coal port is operated by Aurora Energy Services, a Usibelli affiliate.

In the past, UCM had a long term contract with a South Korean buyer. And while they still sell into Korea, they are now moving more coal into South America and other Pacific Rim destinations. “Since 1985, we’ve moved about 16 million tons through Seward,” Denton said. “This year we’ll probably push 900,000 tons—a record for us—and almost half our total production.”

While the coal’s low sulfur quality is a major draw, the price shock we had a few yeas ago sent a loud message to consumers that they need to diversify their supply, Denton explained. “Alaska has a vast, untapped resource,” Denton said. “We’re stable and we don’t have the kind of horrendous weather issues that Australia and other areas have had. Despite our cold winters, you’re not going to see our dragline getting flooded out.” Geographically, when shipped out of Seward, colliers start out closer to many destinations than other ships originating in either Indonesia or Australia.

But in this “green” conscious age, as UCM mines and exports more coal, they also have to ensure that their operations reduce any impact on the region’s environment. To help control fugitive coal dust, increase safety and throughput at the Port of Seward, Aurora Energy Services (AES) upgraded several components of the loading facility. After the installation of a variety of equipment including new engineered coal chutes, AES has drastically reduced dust emissions while speeding up ship loading times by roughly a day. 

Jumbo Dome: Usibelli’s Future
Key to UCM’s future is their Jumbo Dome mine, now under development.  “A large part of our decision to move there has been driven by the export market.  The deposit’s huge amount of low mining ratio reserves, averaging about 3:1, will allow UCM’s coal to remain competitive for generations,” said Denton.

As UCM moves into the area, they’ll probably keep their dragline where it’s currently operating. “It will stay in the Two Bull Ridge area, the pit we’re in now,” Renshaw said. “We’ve got a 20-year, 20 million ton permitted reserve for it to work through.”

If UCM’s sales jump up to 5 million tpy or more, they may re-evaluate that decision. “Though we’re making the roads big enough to accommodate a long dragline move, we believe that our current pit will become a satellite and the new mine will be an all truck-shovel operation,” said Renshaw.

Currently the Two Bull mine only has a three-mile haul to the tipple. Jumbo Dome will be more like 10-mile haul. With that distance to traverse, UCM has considered installing a conveyor system. But they need to be convinced that the Artic winters won’t render the conveyor and belts inoperable.  “At -30ºF to -40ºF or colder, steel will snap, how would those belts react?  If we lose a truck, while we fix it, we’re only down a truck and the coal keeps moving. If we lose our conveyor, then we’re totally down. That’s a risk we’re not sure we want to take,” said Renshaw.

Showing Off: Usibelli’s Commitment to Environmental Excellence
From parts of the mine one can see a small structure peaking out over the trees. That’s Joe Usibelli’s house and the specially designed cupola he had built so he could watch over his operation. It’s also there so the full splendor of the region’s incredible beauty can be better appreciated. And that includes the mine itself.

Because of the Usibelli family’s commitment to the environment and their decision to begin reclamation projects ahead of Federal regulations, “we have the longest record for reclamation in the state,” said Bartly Coiley, UCM’s manager of environmental affairs.  “We were reclaiming six years before it was ever required when SMCRA was implemented in 1977.  Then, like now, so many of our employees lived near the mine.  They wanted the area reclaimed so that it would remain the beautiful place it was and is today,” said Coiley.

Post mining land use is mainly wildlife and habitat restoration. “We’re doing all we can to make sure that the wildlife can come back and live where we had mined years before. We have a lot of moose, bear, caribou, eagles, wolves and lynx around us, as well as other animals.  We are committed to ensuring they’ll be able to safely and productively live where we’ve previously mined,” Coiley said. “Joe and the entire Usibelli family have always maintained a proactive stance on environmental issues. They’ve been incredibly positive on many of the initiatives we have put forth, above and beyond existing regulations. If we can justify it from a business perspective, we’re generally given the opportunity to move forward.”

Perhaps because of this, Usibelli, compared to most surface mines today has an open door policy when it comes to visitors and tours. Being that they are so close to Denali National Park and all the tourism traffic, they like to show off their reclamation to the generally misinformed masses. “It’s taken us decades to accomplish this level of environmental care, and we’re not shy about sharing it with the general public. They need to see it can be done, and done right,” said Renshaw.

Buchsbaum is a Denver-based freelance writer and photographer specializing in industrial subjects. He can be reached through his Web site at or by phone at 303-746-8172.