The room and pillar operation, which pulls from the Hiawatha seam, is now operating Sections I and II seven days a week, three shifts a day.

“As a result, our June coal output is now on pace to increase 30 percent over the previous average monthly production," said company president Alexander Walker.

“With mining operations in Section II now underway, our coal production should continue to scale at a much more aggressive pace.”

After six months of planning, officials said, mining is now “progressing well” at the complex.

“Based on the significant and growing global demand for our high-BTU, compliant coal, we are now well positioned to make measurable progress towards accomplishing several key financial and operational objectives in the months ahead," America West said.

The seam at the Horizon mine measures approximately 7ft and has averaged 280,000 tons of coal per year in the last four years. As a multiple-section mine, the company said it anticipates output levels between 600,000t and 2 million tons annually.

The company underwent a name change from Reddi Brake Supply Corporation to America West Resources in March. Horizon is operated by its subsidiary Hidden Splendor Resources.