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An
experimental variance
to the approximate original
contour requirements of the
federal surface mine law
shows promise from both the
policy and environmental
viewpoints
Approximate original contour reclamation:
An alternative
in
steep slope terrains
By Carl
E.
and James
Z
i
p pe r,
C.
Bell
W.
HEN the Surface Mining Control
and Reclamation Act of
1977
W
(SMCRA) was signed into law in
August of
1977,
the event
was
hailed
as
a vic-
tory for environmental
interests.
The legisla-
tion put severe restrictions on
spoil
handling
procedures used by coal surface mining
operations and has produced substantial im-
provements in overall reclamation practices.
Fundamental to SMCRA are its ’’approx-
imate original contour” provisions, which
specifically require surface mining operators
to
“. .
.grade in order to restore the approx-
imate original contour
of
the land with all
highwalls, spoil piles, and depressions eli-
minated..
.”
[Sec.
515(b)3].
The original con-
Lee Daniels,
Carl
E.
Zipper is a research associate,
W
Lee
Daniels is an assistant professor, and James C.
Bell
is a former research associate with the Depament
of Crop and Soil Environmental Sciences, Virginia
Polytechnic Institute and State Universiry, Blacks-
burg,
24061.
tour requirement is applied separately to
steep-slope mining situations (where pre-
mining slopes exceed 20 degrees) by Sec-
tion 515(d)2, which states that the mining
operation will “return the site to the appro-
priate original contour, which material will
maintain stability following mining and re-
clamation.”
Reclamation
by
approximate original con-
tour (AOC) is a practice of recent origin in
the central Appalachian region of south-
western Virginia, eastern Kentucky, and
southern West Virginia where pre-SMCRA
state laws did not require complete backfill-
ing of highwalls
(3).
Since the late 1!J7Os,
a majority of central Appalachian mined
land has been reclaimed to AOC.
Herein, we examine an experimental var-
iance from the steep-slope reclamation re-
quirements defined by Section 515(d) of
SMCRA. The purpose for seeking the var-
iance was to investigate the environmental
July-AUgUSt
1989
279
and economic feasibility of using an alter-
native to conventional AOC reclamation
practices
in
steep-slope terrain to produce
a carefully constructed surface-mined area
of higher land use potential. The major ele-
ments of the experimental reclamation prac-
tice could be applied to steep-slope mining
on a nonexperimental basis if a variance
from SMCRA’s AOC provisions were ob-
tained. To obtain a variance, a mining firm
must comply with the requirements of
SMCRA Section 515(e), which governs
steep-slope variances, or if the operation
were judged to constitute a modified moun-
taintop removal with the requirements of
Section 515(c), which applies to situations
“where the mining operation will remove an
entire coal seam or seams running through
an upper fraction of a mountain, ridge, or
hi1
1
’
’
[
515(c)( 2)]
.
Implementation of the variance on an ex-
perimental basis
in
southwestern Virginia in-
dicates that its environmental and economic
effects are superior to those of standard AOC
reclamation practices in steeply sloping
Appalachian terrain. After reviewing those
effects, we believe that changes
in
laws and
regulations could be made that will lower
barriers to more widespread implementation
of the demonstrated procedure.
AOC
in central Appalachia
SMCRA defines approximate original
contour as follows: “That surface configu-
ration achieved by backfilling and grading
The primary equipment used to move
spoil at Amos Ridge
is
similar to
equipment used at contour surface mines
throughout central Appalachia: dozers,
wheel-loaders, and off-road haul trucks.
tion achieved by backfilling and grading
of
the mined area
so
that the reclaimed area
. . .
closely resembles the general surface
configuration of the land prior to mining and
blends into and complements the drainage
pattern of the surrounding terrain, with all
highwalls and spoil piles eliminated..
.”
[Sec.
701(2)].
The act requires mining operators to re-
claim all mined acreage to AOC unless a
variance is obtained. Two major require-
ments for a variance are these: First, the
planned reclamation practices must improve
the watershed and produce land suitable for
an equal or better economic or public use,
such as a residential, commercial, indus-
trial, or public use, including recreational
facilities [Sec. 515(e)(2) and (3)]. Second,
if mountaintop removal mining is
used,
agri-
cultural land use is also eligible for variance
consideration [Sec. 515(c)(3)]. Federal reg-
ulations require that there be a ”reasonable
likelihood”
that
the planned post-mining use
will be achieved [30CFR 816.133(c)(l)]. The
current interpretation of this regulation is to
require that the reclamation plan included
in
the mining permit application provide for
implementation of the land use for which the
land is being made suitable.
Appalachian terrain is comprised of flat-
bedded sedimentary rock strata interbedded
with coal seams. Long-term geologic ero-
sion has created a landscape of relatively flat
ridgetops, steep sideslopes with thin col-
luvial soils, and alluvial bottoms. This high
degree of dissection causes sideslopes to be
the dominant landforms; these form an in-
tricate landscape pattern of points and hol-
lows.
Slope
gradients in excess of 20 degrees
are common. Most residential and commer-
cial development has taken place
in
alluvial
areas, flat lands with deep soils and access
to water and transportation.
Abundant coal outcrops on sideslopes
create ideal conditions for mining. Contour
mining operations move laterally along the
outcrops, removing overburden to expose
coal. Such operations have been profoundly
affected by SMCRA. The current conven-
tional practice is to rebuild the topography
by trucking a majority of the overburden
up-
ward from the mining pit to the “backfill”
so
as to cover the “highwall” left
by
the min-
ing cut. However, volumetric expansion of
the blasted rock generates “excess spoil
,”
that is, spoil that cannot be backfilled. Thus,
the original contours cannot be duplicated
exactly. Companies often dispose of excess
spoil
in
hollows below the mining benches.
Construction of a “hollow
fill”
[515(b)(22)]
includes removal of vegetation and/or top-
soil, placement of spoil
in
the hollow
to
in-
sure stability and drainage and to prevent
damage to natural water courses, and cap-
ping the
fill
with a surface medium that
will
support vegetation. Landslides resulting
from uncontrolled spoil placement and sub-
sequent saturation by surface waters were a
major pre-law environmental problem
(7).
Thus, hollow fill construction is closely re-
gulated at the federal [30CFR 816.71-741 and
state levels
(8).
Recent research on 22 deliberately chosen
backfills on 12 separate mining sites indi-
cates that highwall backfills constructed
in
steeply sloping terrain are,
in
some cases,
potentially unstable and erodible
(I,
2).
These potentially unstable backfills are an
unintended, undesirable result of SMCRA’s
AOC provisions. Moreover, our investiga-
tions of the alternative experimental prac-
tice demonstrate the availability of a variance
reclamation method that allows contour min-
ing firms to rebuild steeply sloping point-
and-hollow terrain to create more stable
configurations.
The variance on steep slopes
An experimental variance to AOC prac-
tices has been investigated
in
Wise County,
Virginia
(16).
At the Amos Ridge site, the
premining topography consisted of a series
of finger ridges protruding from a central
“spine,” Amos Ridge. Excepting the tops of
the fingers, slopes on nearly all the land be-
ing mined exceeded 20 degrees.
The Amos Ridge Coal Company has
mined with an experimental practice vari-
ance [under Sections 711 and 515(e) of
SMCRA] obtained with the cooperation of
the
U.
S.
Office of Surface Mining Reclama-
tion and Enforcement (OSMRE) and the
Virginia Division of Mined Land Reclama-
tion. Contour mining was conducted across
280
Journal
of
Soil
and Water Conservation
Isometric representations of the
premining and postmining topographies
at Amos Ridge. The area represented
covers about
100
acres; the southeastern
corner is located at the bottom of each
image. The postmining topography (right,
top) produced
by
the experimental
”landscape alteration” mining and
reclamation method. The outslopes of the
three hollow fills are represented by the
triangular-shaped surfaces between the
undisturbed ends of the finger ridges
along the eastern edge. The premining
topography (right, bottom), showing
finger ridges protruding from the central
“spine” of Amos Ridge at the western
edge. Below is a photograph of the
outslope of the first (southern-most)
hollow fill at Amos Ridge, as viewed from
the east.
four finger ridges and three intervening hol-
lows while removing
three
seams
of coal (the
low splint seam, and its upper and lower
markers) running through the upper fraction
of these ridges. Rather than completely re-
building the finger ridges to AOC, the firm
used spoil generated from the finger ridges
to construct three hollow fills. The result is
a relatively large, near-level “bench,” a ter-
race-like landform extending over the
stripped fingers and filled hollows that
covers about 12 of the 72 acres under per-
mit. The objective of producing a usable,
stable landform was pursued by construct-
ing the hollow fill outslopes at 3:l grades,
rather than the maximum-allowable 2: 1
grade (30CFR 816.71) and
by
building plant
growth media with selected, uncompacted
soil and spoil materials. All highwalls were
backfilled. With the exception of the AOC
and hollow fill construction provisions (two
hollow fills were constructed using experi-
mental techniques), all SMCRA perfor-
mance standards and Virginia regulatory
standards were met. We term this form of
mining and reclamation as “landscape alter-
ation” mining.
Comparing the techniques
Our analyses indicated that there are a
number of reasons why the landscape altera-
tion
mining strategy is superior to mining
by
AOC
on this site.
Environmental benefits.
The landscape
alteration landform at Amos Ridge will be
more stable and less prone to erosion than
the steeply sloping AOC backfills that would
have been generated by conventional back-
fill, grade, and compaction reclamation
methods. The chances of slope failure are
less because the total area of reconstructed
steep slopes is less. If future backfill failures
were to occur at the landscape alteration
mining site, the existence of the broad bench
at the base of the backfills would limit off-
site effects.
Potential erosion of surface soil from the
reclaimed landscape also is reduced by im-
plementing the landscape alteration strategy.
Long, uninterrupted steep slopes and sur-
face silt contents favor erosion
(I,
2,lO).
The
landscape alteration strategy reduces the in-
cidence of steep slopes as a proportion of
total area. Those slopes that do occur are
interrupted by the bench at the highwall
backfill base. The operator’s ability to selec-
tively place backfill surface materials to
limit silt content is increased by the spoil
handling flexibility inherent in the landscape
alteration plan
(14).
An associated hydrologic benefit of the
alternative technique will be a reduction in
rainfall runoff. Infiltration of incident rain-
fall is favored by the near-level bench area
covered with a porous, uncompacted mine
soil. SMCRA sections regulating AOC var-
iance are very specific regarding watershed
effects: steepslope variances must improve
watershed control [515(e)(3)] and mountain-
top removal variances must improve drain-
age control while not damaging natural
water courses [515(c)(4)(C) and
(D)].
This situation occurs in contrast to the
common results of conventional steep-slope
mining, where operators are required to
compact AOC backfill surfaces to ensure
stability [30CFR 816.102(c)]. This compac-
tion limits infiltration into the backfill. The
only interruption of AOC slopes often is an
abandoned haul road, which tends to con-
centrate runoff, thereby increasing its ero-
sive power. The net effect of a conscien-
tiously performed landscape alteration stra-
tegy
is
that watershed control is improved
by
decreasing stream peak flows, a definite
benefit
in
the headwaters of flood-prone
watersheds
(9).
If events in future years cause sharp in-
creases in coal prices, economic pressures
will dictate that many current Appalachian
contour mines be considered for remining.
The use of the landscape alteration technique
now
will
enhance remining operators’ abil-
ities to limit potential off-site environmen-
tal effects. Smaller quantities of previously
handled spoil will need to be moved to get
at unmined coals because the finger points
have not been reconstructed totally. The
bench areas below the highwall backfills will
tend to isolate larger portions of the envi-
ronmental impacts of remining from undis-
turbed areas.
There is one major advantage to the AOC
strategy relative to the landscape alteration
strategy: Less area is disturbed because few-
er hollow fills are used for spoil disposal.
However, this holds only if AOC backfill
failures and erosion do not adversely affect
unmined area downslope. At the Amos
Ridge site, the landscape alteration mining
plan disturbs about
10
percent more land
than the AOC alternative.
Land
use benefits.
The landscape altera-
tion method enhances the reclaimed land use
potential in two ways: by producing a land-
form with a near-level surface and by en-
abling operators who choose to use blasted
overburden as a topsoil substitute
[515(b)(5)]
to isolate materials to construct a mine soil
medium appropriate for that use
(5)
at min-
imal expense. This ability to isolate topsoil
substitute materials is a consequence of the
availability of multiple spoil disposal areas
during landscape alteration mining, in con-
trast with steep-slope AOC mining
(14).
Flat lands with improved use potentials
can provide numerous benefits to the resi-
dents of central Appalachia. Because of the
mountainous terrain, coal mining is the only
major industry in many communities;
un-
employment and poverty rates are high
(6).
The majority of land that is sufficiently
“flat” to support commercial centers and
residential communities is adjacent to
streams. The very nature of the central Ap-
palachian terrain-steep slopes with thin
soils-makes these areas floodprone. Crea-
tion of flat land after mining, permitted with
variances from SMCRA’s AOC require-
ments, will benefit Appalachian residents if
such areas can be developed to support resi-
dential, commercial, and/or industrial land
uses
(10).
Reclaimed mine sites can also support
livestock and softwood timber production.
Establishment of such enterprises can assist
Appalachian communities by providing
additional income and employment oppor-
tunities.
In
Virginia, appropriately reclaimed
mined areas appear to be particularly well-
suited to the production of Eastern white
pine
(12,
15).
Construction of relatively flat
areas
with productive soils is vital
to
the pro-
fitability of such enterprises.
Mining
operation benefits.
Mining and
reclamation operations at the Amos Ridge
site have been studied intensively, and the
techniques offer potential advantages to the
mining industry as well as to local commun-
ities.
Machinery operation and overburden
movement data from the Amos Ridge site
from January
1984
through August
1985
formed the basis of our study
of
mining costs
(18,
20).
We collected additional data from
other steep-slope contour mining sites where
conventional AOC procedures were used
and developed data processing and cost
modeling software for application to the
Amos Ridge data
(17,
19).
We used this
system to model the economics of landform
construction, comparing the cost of mining
using the landscape alteration techniques to
our estimate of what the cost of mining
would have been under conventional AOC
practices
(14).
Costs included all on-site
operations-blasting, spoil movement and
placement, and reclamation.
The cost of mining to produce the land-
scape alteration landform was less than the
likely cost under AOC mining. Depending
upon the spoil movement assumptions, the
estimated cost difference varied between
14
and
58
cents per ton of coal produced. The
primary reason for this cost difference is the
change in topography brought about
by
min-
ing. To reconstruct the terrain using AOC
methods, far greater quantities of spoil
would have been moved upward from the
point of origin. The landscape alteration
method, on the other hand, results in large
quantities of spoil being moved laterally and
downward to construct level benches and
hollow fills. Had the mining operation been
conducted in more conventional fashion, the
economics of spoil handling would have re-
stricted the mining to more favorable cuts;
thus, coal recovery was increased by the
landscape alteration method.
From
an
operational standpoint, a number
of nonmodelled factors also favor produc-
tion of the altered landform
(14).
The land-
scape alteration strategy offers increased
operational flexibility. The near-level areas
can
be
used for equipment storage and main-
tenance during the course of mining. Be-
cause of the opportunity to haul, carry, and
push material laterally into the hollow fills,
the operator has a greater opportunity to
avoid steep, uphill hauls on bad weather days
when slick roads reduce hauler efficiency.
Also, the alternative strategy requires less
wear and tear on machinery because of the
reduction in steep, uphill hauling and steep-
slope grading. The above factors will have
direct eff’ects upon mining cost. There is also
a safety factor-the inherent danger of oper-
ating large machines at the top of steeply
sloping, nonconsolidated banks of earthen
materials
(10).
This situation occurs less fre-
quently during construction of the landscape
alteration landform.
The operator’s ability to limit off-site en-
vironmental effects without incurring exces-
sive costs is enhanced by the spoil-handling
flexibility inherent in the alternative strategy.
The availability of multiple spoil disposal
areas allows selective handling and place-
ment of overburden materials to construct
mine soils cost-effectively with desired re-
vegetation properties. Also, miscalculations
of
spoil
volumes or spoil disposal capacities
can be accommodated easily through minor
adjustments in the elevation of the bench
surface.
In contrast, the spoil disposal capacity of
a stable AOC backfill is defined rigidly by
a combination of the the physical limitations
placed upon spoil disposal by steep-slope
terrain and the SMCRA requirements that
the backfilled spoil “completely cover the
highwall” and “maintain stability following
mining and reclamation” [Sec. 515(d)(2)].
Thus, miscalculations of spoil volume and
swell, backfill capacities, or hollow
fill
capacities can have costly consequences
in
an AOC mining regime. Excess spoil dis-
posal difficulties or large cost differentials
between excess spoil disposal and highwall
backfilling, can give an operator an incen-
tive to overfill AOC backfills, producing the
convex forms implicated as sources of in-
stability
(1,
2)
and establishing sources of
excessive erosion due to the steep slopes
in
the lower portion of the backfill
(10).
Aesthetic benefits.
The effect of uncon-
trolled surface mining on natural aesthetics
was a major problem prior to development
and passage of SMCRA [Sec. 101(c)]
(11,
13).
The landscape alteration strategy does
not create exposed highwalls or barren out-
slopes, two major features of prelaw, steep-
slope mining that, according to many ob-
servers, impaired natural beauty
(7).
The terraced landscape produced by the
landscape alteration strategy is not meant to
give a “natural” appearance by simulating
an undisturbed mountainside. Because the
practice is not widespread, no data exist to
define the impact of the practice upon nat-
ural beauty, as perceived
by
the general
public. However, terraced landscapes are
282
Journal
of
Soil
and
Water
Conservation
produced commonly by people in mountain-
ous
regions throughout the world.
The
method’s
future
If
implemented effectively in appropriate
locales within the central Appalachian re-
gion, more widespread use of “landscape
alteration’’ mining and reclamation practices
would bring many benefits to the region. At
Amos hdge, implementation of this method
reduced the environmental impact of min-
ing, relative to current standard AOC meth-
ods, by improving watershed control and en-
hancing the stability of the reclaimed area.
An indirect environmental benefit also re-
sults from the increase
in
coal recovery
brought about by the experimental practice.
Mining costs per ton were less at Amos
Ridge, while the use potential of the re-
claimed land was improved.
The results of the Amos Ridge case study
visions require that an approved postmin-
ing land use improve watershed control and
that reclaimed areas be “suitable” for the
proposed use. In the case of land being cre-
ated to support commercial forestry, con-
struction of the deep, uncompacted mine
soils that will support vigorous timber
growth
(12)
would be essential to meeting
both requirements.
Another possible regulatory action would
be
to liberalize regulations implementing the
AOC variance requirement that the re-
claimed land be “suitable” for an approved
“equal or better economic or public use”
[515(c)(3) and 515(e)(2)], that is, to develop
criteria for selectively waiving the require-
ment that the proposed land use actually be
implemented at the immediate conclusion of
mining. These criteria might include a de-
monstrated community need for the pro-
posed land use, as certified by an indepen-
dent third party. Given that a genuine need
in
SW
Virginia.
In Proc., 1985 Symposium on
Surface Mining, Hydrology, Sedimentology, and
Reclamation. Univ.
Ky.,
Lexington. pp. 243-247.
2. Bell, James C., W.L. Daniels, and C.E. Zipper.
1989.
lhe pwtice of
’
’approximate original con-
tour’
’
in the central Appalachians:
I.
Slope
srability
and
erosion control.
Landscape and Ur-
ban Planning (In press).
3. Council on Environmental Quality. 1973.
Coal
surface mining
and
reclamation:
An
environmen-
tal and economic assessment.
Rpt
.
to the Senate
Comm. on Interior and Insular Affairs. Wash-
ington, D.C.
4. Dappolonia, Inc.
1980.
Abandoned coal mined
land inventory.
Project 78-411. Rpt. for Com-
monwealth Va. Div. Mined Land Recla., Big
Stone Gap, Va.
5.
Daniels, W.L., and D.F. Amos. 1984.
Gener-
ating productive topsoil substitutes from hard
rock overburden in the southern Appalachians.
Environ. Geochem. and Health 7: 8-15.
6.
Kraybill, David
S.,
Thomas
G.
Johnson, and
Brady
J.
Deaton. 1987.
Income uncertainty and
the quality
of
life: A Socio-Economic Study of
Virginia’s Coal Counties.
Bull. 87-4. Va. Agr.
Exp.
Sta.,
Blacksburg. 87 pp.
7. Mathematica, Inc. 1974.
Design
of
sugace min-
ing systems in eastern finzucky.
Rpt.
for
the Ap-
palachian Regional Commission and Kentucky
Department
of
Natural Resources. ARC-71-66-
should be applicable in other areas of cen-
tral Appalachia. The machinery and haul-
back mining methods used at the site are
exists, the“reasonab1e likelihood” that the
land use for which the site is prepared would
actually be implemented is very real. Thus,
Tl.’ NTIS PB242651. Frankfort, Ky.
’*
~~sss”~~~~~~hc~~~~~~~~~~
f:yi$::
Mining Control and Reclamation Act
of
1972
typical of steep-slope surface mining opera-
tions. The steeply sloping point-and-hollow in communities where housing sites are in
short supply, for example, the mining
firm
Nat-
Acad. Press,
Washington,
D.C.
ing:
soil.
coal.
and
socien!
Nat. Acad.
press.
9.
National Research Council. 1981.
Surface min-
terrain at Amos Ridge is common through-
out the region. The question is: What legal
and regulatory changes could bring about
more widespread use of this new alternative
mining practice?
First, state regulatory agencies must scru-
tinize more closely AOC backfill construc-
tion activities, particularly in steeply slop-
ing areas. There are contour mining areas
on
which there is little hope that the land
can be returned “back to original contour”
in
a stable fashion. Slope steepness is a
primary factor influencing backfill stability
(10).
Applications by companies to mine in
steeply sloping regions should be scrutinized
carefully. Stability modeling during the per-
mitting phase must be performed conser-
vatively
(10)
and conscientiously. Regulatory
agencies must assure that the modelled de-
sign assumptions are incorporated into back-
fill
construction procedures. Closer scrutiny
of
AOC backfills in areas with extreme
slopes will stimulate mining firms to con-
sider alternative mining locales and/or
methods.
Second, federal and state laws and regula-
tions governing AOC variances should con-
tinue
to
be liberalized. One possible action
would be to define commercial forestry as
a postmining land use eligible for such a
variance. Commercial timber production is
potentially profitable on Virginia mine soils
(15)
and
of
greater economic value than the
usual premining, unmanaged forest. Forest-
ry
is a well-established industry in the Appa-
lachian region, familiar to a majority
of
landowners. The steep-slope variance pro-
could be granted a variance to produce a site
that is physically suited for housing (access
to public roads, potential access to water and
waste disposal, and on stable ground) with-
out accepting the obligation
to
arrange
fi-
nancing and to physically produce housing
on that site. This change would remove a
major impediment to mining firms’ will-
ingness to create beneficial landforms.
Finally, hollow-fill construction regula-
tions should be liberalized. The Office of
Surface Mining Reclamation and Enforce-
ment is moving in this direction, as evi-
denced by the experiment at Amos Ridge.
However, the variations in requirements of
state programs shows changes are possible
at the state level. A primary facet
of
hollow-
fill design criteria should be the outslope
gradient. Where the configuration of the
hollow is appropriate and reliable drainage
of the fill body is assured, hollow-fill stabil-
ity would be enhanced by providing incen-
tives to reduce outslopes to gradients below
the maximum allowable
2:l
(27-degree)
slopes. Lower gradients on the outslopes
will make fills less prone to failure and ero-
sion, which should make the mode of place-
ment of materials in the fill less critical to
the ultimate stability of the final structure.
This, inturn, should reduce the need for reg-
ulatory oversight and enhance the operators’
willingness to engage in hollow-fill con-
struction procedures.
REFERENCES CITED
1.
Bell, James C., and
W.
L.
Daniels. 1985.
Four
case studies
of
slope stability on su#ace mined
lands returned to approximate original contour
Wishington, D.C.
10.
National Research Council, 1984.
Highwall
elimination and return to approximate original
contour
as
required by the Sulface Mining Con-
trol and Reclamation Act of
1972
Nat. Acad.
Press, Washington, D.C.
11.
Simpson, John W. 1985.
The emotional land-
scape and Public
Law
95-82
Landscape Ar-
chitecture (May-June): 60-63.
12. Torbert, J.L., A.R. Tuladhar, J.A. Burger, and
J.C. Bell. 1988.
Minesoil property effects on the
height
of
ten-year-old white pine.
J.
Environ.
Quality 17(2): 189-192.
13. U.S. Department of the Interior. 1967.
Surface
mining and our environment.
Washington, D.C.
14. Zipper, C.E. 1986.
Opportunities for improved
surface mine reclamation
in
the central Ap-
palachian coal region.
Ph.D. diss. Va. Polytech.
Inst. and State Univ., Blacksburg. 121 pp.
15. Zipper, C.E. 1987.
An economic analysis of beef
cow-calf operations and eastern white pine
timber plantations on surface mined lands
in
southwest Virginia.
M.S. res. paper. Va. Poly-
tech. Inst. and State Univ., Blacksburg. 123 pp.
16. Zipper, C.E. 1988.
Amos Ridge experimental
practice-final report.
Off. Surface Mining
Reclam. and Enforcement, Pittsburgh,
Pa.
17. Zipper, C. E., A. Chakraborty,
E.
Topuz, and
W. L. Daniels. 1985.
A
surface mining simulator
for application in steep slope topography.
In
Proc., 1985 Nat. Symp. on Surface Mining,
Hydrology, Sedimentology, and Reclam. Univ.
Ky., Lexington. pp. 25-28.
18.
Zipper,
C.
E., Andy T. Hall and W. L. Daniels.
1985.
Costs of mining and reclamation at a con-
tour sulface mine in steep slope topography.
In
Proc., 1985 Nat. Symposium on Surface Min-
ing, Hydrology, Sedimentology, and Reclam.
Univ. Ky., Lexington. pp. 193-200.
19. Zipper, C. E., and
W.
L.
Daniels. 1986.
COSISUM: A system for analysis of opemtional
cost data from coal sulface mines-A user
S
guide.
Bull. 86-1. Va. Agr. Exp.
Sta.,
Blacksburg. 120 pp.
20. Zipper, C.E., W.L. Daniels, and James C.
Bell.
1989.
lhe pmctice
of
“appmimate original con-
tour
’ ’
in the central Appalachians.
II
Economic
and environmental consequences
of
an alter-
native.
Landscape and Urban Planning (In
press).
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