The Wyodak mine is a coal mine located 6 miles east of Gillette

Gillette, Wyoming

Gillette is a city in and the county seat of Campbell County, Wyoming, United States. The population was 29,087 in 2010. Gillette is a city centrally located in an area involved with the development of vast quantities of American coal, oil, and coal bed methane gas...

, Wyoming

Wyoming

Wyoming is a state in the mountain region of the Western United States. The western two thirds of the state is covered mostly with the mountain ranges and rangelands in the foothills of the Eastern Rocky Mountains, while the eastern third of the state is high elevation prairie known as the High...

 in the United States in the coal-rich Powder River Basin

Powder River Basin

The Powder River Basin is a geologic region in southeast Montana and northeast Wyoming, about east to west and north to south, known for its coal deposits. The region supplies about 40 percent of coal in the United States. It is both a topographic drainage and geologic structural basin...

. The operation is an open pit

Open-pit mining

Open-pit mining or opencast mining refers to a method of extracting rock or minerals from the earth by their removal from an open pit or borrow....

 mine that utilizes a truck and shovel mining method to produce a low-sulfur, sub-bituminous coal that is used for domestic energy generation. The mine ships its coal to the adjacent Wyodak power plant and to other customers via railroad. The mine is operated by Wyodak Resources Development, a subsidiary of the Black Hills Corporation

Black Hills Corporation

Black Hills Corporation is a Rapid City, South Dakota diversified energy company that is an electric and gas utility in South Dakota and Wyoming and sells power throughout the American West....

.

As of 2009, Wyodak had reserves of 294mm tons of sub-bituminous coal and a maximum permitted production capacity of 10mm tons per year. Typical annual production has been in the 5-6mm ton range for the last several years though. In 2008, the mine produced just over 6.0 million short ton

Short ton

The short ton is a unit of mass equal to . In the United States it is often called simply ton without distinguishing it from the metric ton or the long ton ; rather, the other two are specifically noted. There are, however, some U.S...

s of coal, making it the 30th-largest producer of coal in the United States.

The average quality of the coal produced from the Wyodak Mine is 8,050 BTU/lb, 0.40% Sulfur, 6.0% Ash, and 0.94% Sodium (of the ash). Train loading operations at the mine are done by a flood loading system that is coupled to a "weigh-in-motion" track scale system. Silo capacity at the mine's rail loop, which can accommodate a single unit train, is 24,000 tons.

History

Mining operations at the mine site first began around 1918 with the establishment of the Peerless Mine. The Peerless Mine was an underground room and pillar

Room and pillar

Room and pillar is a mining system in which the mined material is extracted across a horizontal plane while leaving "pillars" of untouched material to support the roof overburden leaving open areas or "rooms" underground...

 operation that mined coal near the outcrop

Outcrop

An outcrop is a visible exposure of bedrock or ancient superficial deposits on the surface of the Earth. -Features:Outcrops do not cover the majority of the Earth's land surface because in most places the bedrock or superficial deposits are covered by a mantle of soil and vegetation and cannot be...

 of the Wyodak seam. Though the operation went out of business in 1925, it left behind underground workings which were uncovered and mined through by the Wyodak mine in the 1950s.

The modern Wyodak mine was established in 1923 to provide coal for power plants that supplied energy to the Homestake Mine

Homestake Mine

Homestake Mine is the name for several mines in the United States:* Homestake Mine , listed in the National Register of Historic Places* Homestake Mine , home of the future Deep Underground Science and Engineering Laboratory....

for its mining and milling operations. In 1956, the Black Hills Corporation

Black Hills Corporation

Black Hills Corporation is a Rapid City, South Dakota diversified energy company that is an electric and gas utility in South Dakota and Wyoming and sells power throughout the American West....

 purchased the mine from the Homestake Mining Company

Homestake Mining Company

The Homestake Mining Company was one of the largest gold mining businesses in the United States from the 19th century through the beginning of the 21st...

by exercising an option that was negotiated during its purchase of the Wyodak power plant in 1954.

It is believed that Wyodak is the oldest, continually operated coal mine in the United States.

Production

Year	Coal Production	Employees
2009	6,016,063	121
2008	6,017,311	116
2007	5,049,232	109
2006	4,698,473	66
2005	4,701,625	68
2004	4,780,104	59
2003	4,812,346	56
2002	4,052,374	55
2001	3,518,162	53
2000	3,050,325	43
1999	3,179,585	43
1998	3,280,157	43
1997	3,250,969	46
1996	3,198,544	47
1995	2,984,000	51
1994	2,795,942	52
1993	3,027,356	57
1992	2,257,551	58
1991	2,741,809	57
1990	2,907,639	63
1989	2,349,135	70
1988	2,709,494	71
1987	2,976,398	76
1986	2,584,856	77
1985	2,898,482	72
1984	2,443,831	69