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.