Mine Site Reclamation
Pre-reclamation photo of the Hydraulic Pit near Healy.
In 1855, the first coal mine in Alaska was opened by the Russian-American Company near Port Graham on the Kenai Peninsula.
Renewing lost land
In 1855, the first coal mine in Alaska was opened by the Russian-American Company near Port Graham on the Kenai Peninsula. Fifteen years later in 1870, the first gold mine was established just outside of Juneau. After the construction of the Alaska Railroad in 1917, coal mining began on a large-scale mainly in the Nenana and Matanuska coal fields. Pre-World War II, coal mining in Alaska was dominated by underground mines until 1943 ushered in an era of combined underground and surface mining. By the early 1960s combined mines were replaced by the surface mines that are still used today.
Post-reclamation photo of the Hydraulic Pit near Healy.
Coal and gold are only two of several precious resources produced in the state. Alaska’s six currently producing mines—Fort Knox, Greens Creek, Kensington, Pogo, Red Dog, and Usibelli—produce zinc, silver, gold, lead, and coal. Greens Creek Mine is among the world’s top ten silver producers and Red Dog is one of the world’s largest zinc concentrate producers.
The Reclamation Process
Adit closure at the Inspiration Mine near Skagway.
No matter the size or quality of a deposit, natural resources are finite, and there are now depleted mines located throughout the state. A 1983 broad survey of Alaska’s coal and non-coal abandoned historic mines inventoried 340 sites, but to-date the non-coal inventory remains incomplete for state, private, and Alaska Native lands.
In response to the number of abandoned mines, the Alaska Surface Coal Mining Control and Reclamation Act was approved in May 1983. The act effectively granted the commissioner of the Department of Natural Resources jurisdiction over surface coal mining and reclamation operations in the state. Under the new state and federal laws, the Abandoned Mine Lands Program (AML) was created for the purpose of reclaiming abandoned mines of any type.
“Historic mining occurred in the 1920s through about the early 1970s, and it was all pre-environmental regulation, so these mining companies would go into an area and work for decades and then when they were done they would leave without cleaning up,” says National Association of Abandoned Mine Land Programs Manager Justin Ireys.
Under AML, lands that are eligible for reclamation must have been mined or affected by mining and left in an inadequate reclamation status before August 3, 1977. Additionally, there must be no continuing reclamation responsibility under state or federal law. While there are a variety of mines that would fall under the jurisdiction of the AML, the program’s funding source dictates that coal mine reclamation is the number one priority.
“The Department of the Interior and specifically the Office of Surface Mining collects $0.28 per ton on surface mines and $0.12 per ton on underground mines from around the country. Those monies are then allocated to the different states around the country that have AML programs. Because these funds are generated through the coal industry and by the coal industry, our main priority is to reclaim coal mines. So, [reclaiming] non-coal mines is something that we can do, but only if they are rated as a priority one,” says Ireys.
According to the Alaska Department of Natural Resources Division of Mining, Land, and Water, AML eligible mines are rated using a three-tiered system. Priority one mines present an imminent danger to public health, safety, and general welfare. Priority two mines also present a danger to public health, safety, and general welfare but are not considered to be an extreme danger. Priority three mines are lands that were previously degraded by the adverse effects of mining but do not pose a threat to public safety. Under the AML Program, priority three mines can be reclaimed in conjunction with priority one or two projects or after all priority one and two projects have been completed.
An AML inventory in May 2014 determined that there are a minimum of fifteen large coal project areas and eight non-coal projects that still need to be reclaimed.
Currently, AML is focusing its efforts on a mine a little north of Denali National Park. The area, known as the Healy Creek Strip Pits, was the site of large-scale surface coal mining from the 1920s to the 1960s and is comprised of more than 300 acres of disturbed lands in seven individual pits. Two of the pits, the Hydraulic Pit and the Bill Pit, have undergone the reclamation process; now Ireys’ team is focused on the East Cripple Creek Pit, which is characterized by nearly a mile of significant highwalls.
Not surprisingly, mitigating a mine that boasts a mile long, 100-foot vertical wall is not without some unique challenges.
“The projects that we’ve been working on in the last four or five years have all been really big earthmoving projects and have required the use of scrapers, dozers, excavators, and trucks to basically lay these great big highwalls back. To lay a vertical wall, you have to dig into ground that was previously undisturbed, and we’ll take all the topsoil and the organics and everything that’s there and we’ll push it into a great big pile, so we save it for the very end of our project,” explains Ireys.
Another challenge to a reclamation project of this scope is that workers have just a short three to five month window before permafrost sets in and they are unable to move the land. Secondarily, the short growing season means that once the highwalls are adequately flattened, the salvaged topsoil must be redistributed before Ireys’ team can begin the challenging revegetation portion of the reclamation.
“As we’re doing these big reclamation projects, we’re racing against the clock trying to complete the regrading work, completing the earthwork, and completing spreading the topsoil in time to hopefully be able to do some revegetation work at the very end. But with Alaska we have something called the seeding window and we’re not allowed to go in and do any seeding and fertilizing and revegetation work after August 15 because there’s just not enough time left in the fall for things to start to sprout roots and establish themselves before the freeze comes,” says Ireys.
Highwalls and permafrost are not the only challenges AML has faced.
“There are so many different styles and types of mining, so each reclamation project is pretty unique in and of itself. As we’re going through and we’re developing mitigation plans, we first have to evaluate what type of mine that we’re dealing with and what our end goal is. With underground mines our goal is to essentially prevent access whether by a controlled blast to seal the mine shaft or by installing a steel door to keep the public out while still keeping the mine open for future use,” says Ireys.
Adit closure at the Inspiration Mine near Skagway.
AML is not the only organization that is on the forefront of mine reclamation. Unlike the AML Program, which focuses its efforts on the reclamation of abandoned lands, Usibelli Coal Mine, based out of Healy, contemporaneously restores their mined lands.
“The [Usibelli] mine is, quite literally, in the backyard of the people who work here, so employees have a deep personal stake in protecting the quality of the land, air, and water. Our reclamation program began in 1971, six years before federal law required it,” says Usibelli Vice President of Public Relations Lisa Herbert.
At the cornerstone of Usibelli’s proactive restoration efforts is an exploration program that includes drilling exploratory holes to extract core samples in an effort to evaluate the quality of the coal before commencing mining activities. Once a high-quality area has been identified, Usibelli’s engineers calculate the volume of earth that must be removed to expose the coal in the most efficient way. They also use a 3D model of the area to establish a restoration plan based on the natural contours and patterns of the land.
“Following recontouring, we begin revegetation by aerial seeding with a mixture of grasses and plants that are indigenous to the area. This mixture conditions the land by putting natural nutrients into the soil, while holding it in place until slower growing native plants begin to grow in the area. After seeding, we begin planning seedlings of willow, spruce, alder, and birch. Each year, the mine plants approximately 20,000 to 25,000 trees,” says Herbert.
In the spirit of cleaning up their own backyard, Usibelli’s restoration teams are comprised of a mining engineering intern and three to five high-school or college students. Historically, Usibelli’s interns come from the University of Alaska Fairbanks College of Engineering and Mines and the members of the reclamation crew are often Healy residents or children of mine employees.
“Those working on the reclamation crew come from a variety of backgrounds—for some it may be their first job, and for others it is an opportunity for them to come home from college during the summer and still earn wages to help pay for the following year’s schooling,” Herbert says.
Usibelli has actively restored more than 5,500 acres of mined land in the Healy area.
O’Hara Shipe is a freelance writer in Anchorage.