WV Geological Survey Aims to Finish Coal Reserves Update by 2015

The State Journal
16 October 2012
By Pam Kasey

As the West Virginia Geological and Economic Survey narrows in on a many-year, intensely data-driven update to the amount of coal left to mine in the state, Mitch Blake shared a back-of-the-envelope calculation and his observations on the expected outcome.

"We're not done yet," said Blake, manager of the survey's coal program, of the 20-year effort.

A solid understanding of how much coal is left is crucial for policymakers in a state that, according to Department of Revenue Deputy Secretary Mark Muchow, relied on coal severance taxes alone for 12 percent of its general revenues in the last fiscal year — that's not even counting corporate income tax, franchise tax or other industry-based payments.

But the current estimate of how much coal is left to mine is based on century-old estimates.

The standing estimate

Right now, the federal Energy Information Administration says West Virginia's mineable coal, or "estimated recoverable reserves," stands at about 17.3 billion tons.

The EIA's figure is grounded in the WVGES's early 20th-century county-by-county estimate of the state's original coal "resource" — the broadest measure of coal in the ground — that totaled about 117 billion tons in seams greater than a foot thick.

Following some circa-1990 refinements arrived at through sampling at a limited number of sites, the EIA's number in 1995 for West Virginia's estimated recoverable reserves stood at 19.6 billion tons. And seventeen years later, in 2012, the agency has taken it down to the current 17.3 billion tons — essentially by doing no more than subtracting the 150 million tons or so that has been mined each year.

Blake's own estimate

As a reality check, with the WVGES's update still very much in progress, Blake has dusted off the century-old numbers and refreshed them himself, county-by-county, in a sort of gold-plated back-of-the-envelope estimate based on the very detailed knowledge he and his team have gleaned from 30 years in the field.

Right away, he took the original resource 12 inches or thicker down from 117 billion tons to 93 billion tons, based on places where it has become apparent the early estimates were too high. He placed about 30 billion tons of that in the northern part of the state and 63 billion in the south.

About 67 billion tons of that original native resource was thick enough to mine, he said.

Since the Civil War, about 23.5 billion tons has been mined or lost to mining in the state, leaving 43.5 billion tons of the thick-enough coal still in the ground.

Figuring a little over 10 percent is lost to infrastructure and about 50 percent of what's left is mineable, that comes to about 19 billion tons — pretty close to the EIA's current figure and others, he pointed out.

The estimate to come

But what's really needed is the painstaking from-scratch update the WVGES is nearing the end of now.

That effort, begun in 1995, has two prongs: mapping all the coal that's been mined based on coal-industry maps and, at the same time, mapping all the coal that's left based on core samples and other records.

The survey has mostly mapped and counted the heart of the state's coal, Blake said. What's left is the edges of the coal beds, where seams thin out and the work is more detailed.

When it's done, the new number for the original coal resource will be higher than 117 billion tons, Blake said. That's because, given 20 years and modern technology, the survey is able to account for much more of what's in the ground, both at great depths and right out to the edges of the seams.

But he noted that that doesn't mean the recoverable reserves estimate will be higher than the EIA's 17.3 billion tons.

Neither the EIA's estimate nor his back-of-the-envelope calculation incorporates current detailed knowledge about, for example, seams that will never be mined due to flooding. Blake suggested that the inclusion of that kind of information may bring the new estimated recoverable reserves figure below 17.3 billion tons.

The task is expected to be complete in 2015.