[Federal Register Volume 60, Number 158 (Wednesday, August 16, 1995)]
[Rules and Regulations]
[Pages 42437-42443]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 95-20272]
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DEPARTMENT OF THE INTERIOR
Office of Surface Mining Reclamation and Enforcement
30 CFR Part 948
West Virginia Regulatory Program
AGENCY: Office of Surface Mining Reclamation and Enforcement (OSM),
Interior.
ACTION: Final rule; approval of amendment.
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SUMMARY: OSM is approving an amendment to the West Virginia permanent
regulatory program under the Surface Mining Control and Reclamation Act
of 1977 (SMCRA). The amendment concerns West Virginia's regulations for
the design and construction of durable rock fills. The amendment will
revise the West Virginia program to be consistent with SMCRA and the
Federal regulations.
EFFECTIVE DATE: August 16, 1995.
FOR FURTHER INFORMATION CONTACT: Mr. James C. Blankenship Jr.,
Director, Charleston Field Office, Office of Mining Reclamation and
Enforcement, 1027 Virginia Street East, Charleston, West Virginia
25301, Telephone: (304) 347-7158.
SUPPLEMENTARY INFORMATION:
I. Background on the West Virginia Program
II. Submission of the Amendment
III. Director's Findings
IV. Summary and Disposition of Comments
V. Director's Decision
VI. Procedural Determinations
I. Background on the West Virginia Program
SMCRA was passed in 1977 to address environmental and safety
problems associated with coal mining. Under SMCRA, OSM works with
States to ensure that coal mines are operated in a manner that protects
citizens and the environment during mining, that the land is restored
to beneficial use following mining, and that the effects of past mining
at abandoned coal mines are mitigated.
Many coal-producing States, including West Virginia, have sought
and obtained approval from the Secretary of the Interior to carry out
SMCRA's requirements within their borders. In becoming the primary
enforcers of SMCRA, these ``primacy'' States accept a shared
responsibility with OSM to achieve the goals of the Act. Such States
join with OSM in a shared commitment to the protection of citizens--our
primary customers--from abusive mining practices, to be responsive to
their concerns, and to allow them full access to information needed to
evaluate the effects of mining on their health, safety, general
welfare, and property. This commitment also recognizes the need for
clear, fair, and consistently applied policies that are not
unnecessarily burdensome to the coal industry--producers of an
important source of our Nation's energy.
Under SMCRA, OSM sets minimum regulatory and reclamation standards.
Each primacy State ensures that coal mines are operated and reclaimed
in accordance with the standards in its approved State program. The
States serve as the front-line authorities for implementation and
enforcement of SMCRA, while OSM maintains a State performance
evaluation role and provides funding and technical assistance to States
to carry out their approved programs. OSM also is responsible for
taking direct enforcement action in a primacy State, if needed, to
protect the public in cases of imminent harm or, following appropriate
notice to the State, when a State acts in an arbitrary and capricious
manner in not taking needed enforcement actions required under its
approved regulatory program.
Currently there are 24 primacy states that administer and enforce
regulatory programs under SMCRA. These states may amend their programs,
with OSM approval, at any time so long as they remain no less effective
than Federal regulatory requirements. In addition, whenever SMCRA or
implementing Federal regulations are revised, OSM is required to notify
the States of the changes so that they can revise their programs
accordingly to remain no less effective than the Federal requirements.
A major goal of SMCRA is to ensure adequate reclamation of all
areas disturbed by surface coal mining.
[[Page 42438]]
During reclamation, the removal of coal is followed by backfilling the
mine pit with spoil to return the land to its approximate original
contour. There is usually more spoil than is needed for backfilling
because solid rock that was removed when the mine pit was excavated
increases in volume. This excess rock is typically disposed of as fills
in valleys adjacent to the mine pit. A ``durable rock fill'' is an
excess spoil fill composed of at least 80 percent by volume of
sandstone, limestone, or other rocks that do not slake in water. It is
usually constructed in a single lift or layer and has an underdrain
system that is created by the natural segregation of rock and soil as
it is dumped and rolls downslope.
Background information on the West Virginia program, including the
Secretary's findings, the disposition of comments, and the conditions
of approval can be found in the January 21, 1981, Federal Register (46
FR 5915). Subsequent actions concerning the conditions of approval and
program amendments can be found at 30 CFR 948.10, 948.12, 948.13,
948.15, and 948.16.
II. Submission of the Amendment
In a series of three letters dated June 28, 1993, and July 30, 1993
(Administrative Record Nos. WV-888, WV-889 and WV-893), the West
Virginia Division of Environmental Protection (WVDEP) submitted an
amendment to its approved permanent regulatory program that included
numerous revisions to the West Virginia Surface Coal Mining and
Reclamation Act (referred to herein as ``the Act'', WVSCMRA Sec. 22A-3-
1 et seq.) and the West Virginia Surface Mining Reclamation Regulations
(CSR Sec. 38-2-1 et seq.). OSM grouped the proposed revisions that
concern durable rock fills into one amendment which is the subject of
this notice. The main provisions of the amendment will:
Require that certification forms for durable rock fills be
accompanied by statements attesting to the percentage of non-durable
material, foundation preparation, prohibited materials and sediment
control measures.
Establish criteria for testing spoil material to determine
if it qualifies as durable rock.
Require surface water runoff from areas above and adjacent
to the fill to be diverted into channels designed and constructed to
ensure stability of the fill, control erosion, and minimize water
infiltration.
Require additional sediment control measures if
construction and operation of the fill results in significant non-
compliance with effluent limits or water quality standards.
Prohibit certain materials from being placed in durable
rock fills.
OSM announced receipt of the proposed amendment in the August 12,
1993, Federal Register (58 FR 42903) and invited public comment on its
adequacy. Following this initial comment period, WVDEP revised the
amendment on September 1, 1994, and May 16, 1995 (Administrative Record
Nos. WV-937, and WV-979B). OSM reopened the comment period on August
31, 1994 (59 FR 44593), September 29, 1994 (59 FR 49619), and July 5,
1995 (60 FR 34934), and held a public hearing in Charleston, West
Virginia on September 7, 1993, and a public meeting on October 27,
1994.
III. Director's Findings
A. CSR Sec. 38-2-14.14(b)(4) Certification of Durable Rock Fills
West Virginia proposes to add a provision requiring that
certification forms, submitted to WVDEP by registered professional
engineers overseeing the construction of durable rock fills, be
accompanied by: (1) a statement attesting that the fill contains no
more than 20 percent non-durable material, (2) a statement attesting
that the foundation is proceeding in accordance with the design plans,
(3) a statement that the prohibited materials are not being placed,
deposited, or disposed of into the fill areas, and (4) a statement that
sediment control measures are constructed and being maintained in
accordance with the approved design plans and the terms and conditions
of the permit.
Under 30 CFR 816/817.73(c), the Federal rules require a qualified
registered engineer to certify that the design of a durable rock fill
will ensure the stability of the fill and meet all other applicable
requirements. Furthermore, 30 CFR 816/817.71(h) requires inspections at
least quarterly throughout construction and during critical
construction periods. Following each inspection, the qualified
registered professional engineer must submit certified reports to the
regulatory authority attesting that the fill has been constructed and
maintained in accordance with the approved plan and program
requirements. The report must include appearances of instability,
structural weakness, and other hazardous conditions. West Virginia's
program already contains these requirements. Other than described
above, the Federal rules do not specify that the certified report
include specific statements by the engineer. Since West Virginia
proposes to require a more detailed certification, the Director finds
that subsection 14.14(b)(4) is consistent with the Federal rules and is
hereby approved.
B. CSR Sec. 38-2-14.14(g)(1)(B) Testing of Fill Materials
State and Federal regulations for durable rock fills require that
no more than 20 percent of the volume of the fill may be spoil material
that is not durable rock as determined by tests performed by a
registered engineer and approved by the regulatory authority. Durable
rock is material that will not slake in water and will not degrade to
soil material. West Virginia proposes to add a provision at subsection
14.14(g)(1)(B) that defines soil material, as used in the definition of
durable rock, as material of which at least 50 percent is finer than
0.074 millimeters, which exhibits plasticity, and which meets the
criteria for group symbol ML, CL, OL, MH, CH, or OH, as determined by
the Unified Soil Classification System (ASTM D-2487). In support of
this amendment, the WVDEP submitted to OSM a durable rock testing
protocol which the State would implement in applying its proposed
regulations (Administrative Record No. WV-932). Under the protocol,
rock is first checked for durability by use of standard slake
durability tests. If a rock slakes in water, it is defined as non-
durable, regardless of whether or not it degrades to soil material. A
rock which passes the slake durability test may be further tested under
subsection 14.14(g)(1)(B), on a case-by-case basis, to determine
whether it would potentially degrade to soil particles exhibiting
plasticity and particle size below the specified limit.
The Federal rules do not define soil material in the context of
durable rock fills or provide a testing protocol to determine if rock
degrades to soil material. Since West Virginia's protocol adds a
screening test for durable rock not specifically required under the
Federal regulations, the Director finds that the proposed rule when
applied in conjunction with the State's protocol is no less effective
than 30 CFR 816/817.73(b) and is therefore approved.
C. CSR Sec. 38-2-14.14(g)(8) Drainage Control
WVDEP is proposing to revise subsection 14.14(g)(8) to read as
follows:
Surface water runoff from areas above and adjacent to the fill
shall be diverted into properly designed and constructed stabilized
diversion channels which have been designed, using best current
technology, to safely pass the peak runoff from a 100-year, 24-hour
precipitation event. The channel
[[Page 42439]]
shall be designed and constructed to ensure stability of the fill,
control erosion, and minimize water infiltration into the fill.
The Federal rules at 30 CFR 816/817.73(f) prohibit surface water
runoff from areas adjacent to and above the fill to flow onto the fill
and require water to be diverted into stabilized diversion channels
designed to safely pass the runoff from a 100-year, 6-hour
precipitation event. The Federal rule is more restrictive than the
proposed rule with regard to the location of surface drainage diversion
channels relative to the body of the fill. Under 30 CFR 816/817.73(f),
drainage diversion channels must divert surface runoff from areas
adjacent to and above the fill away from the fill. Such channels must
be located either completely off of the fill or at the interface of the
natural slope and the fill. West Virginia's proposed amendment would
allow drainage diversion channels to be located anywhere, including on
the fill itself, provided that the channels are designed and
constructed to ensure the stability of the fill, control erosion, and
minimize water infiltration into the fill.
The Federal requirement to divert runoff water away from durable
rock fills was adopted on March 13, 1979, as permanent program rule 30
CFR 816.74(d). While there were no specific comments pertaining to
diversions of water away from durable rock fills, commenters stated,
with regard to head-of-hollow fills, that stabilized diversion channels
``off of the fill'' created an unnecessary disturbance and that
channels on the fill could protect that portion of the fill from
erosion. In the preamble, OSM justified the requirement by stating that
``Diversion of water away from the fill surface is considered sound
engineering practice'' and cited several engineering references. OSM
concluded that, while more area will be disturbed where diversions are
placed off of the fill area, ``less environmental harm will result from
retaining the requirement to build diversions off the fill
structures.'' (44 FR 15206).
The intent of the Federal rule prohibiting runoff diversion onto
the fill, as explained in the preamble, was to prevent water erosion of
fill material and infiltration into the fill. West Virginia's proposed
rule, while not restricting the location of surface drainage diversion
channels, specifically requires control of erosion and minimization of
water infiltration, thus preserving the intent of the corresponding
Federal regulation. The proposed rule prohibits the diversion of water
into or through the fill because diversions must be designed and
constructed to minimize water infiltration.
An OSM ad hoc technical committee on excess spoil disposal
considered the proposed amendment for technical sufficiency. The
committee concluded that appropriate surface drainage control for
durable rock fills can be accomplished under the proposed West Virginia
amendment. The amendment's proposed language and the other excess spoil
provisions of the West Virginia regulatory program provide clear
authority for WVDEP to require permit applications containing
demonstrations and technical analyses addressing adequate hydraulic
design--including channel capacity, erosion control, and minimizing
infiltration into the fill mass. The committee also considered that a
proper channel design could overcome potential hydraulic problems from
intersecting flows at channel and terrace junctions, changes in channel
gradient, or anywhere hydraulic jump and/or overtopping would be likely
to occur. The committee recommended to WVDEP that a permittee show
designs and specifications, based upon maximum design velocities, which
would encompass riprap sizing, gradation, bedding, filters, and all
channel material placement. The design and specification should also
address how infiltration will be minimized (e.g., through channel
liners, etc.) and assure that runoff adjacent to the channel can enter
the drainage diversion system with a minimum of erosion. The committee
underscored the importance that runoff not be allowed over the face of
the fill in locations other than the diversion channel. Finally, the
committee provided WVDEP a series of recommendations on key areas of
the durable rock fill drainage control system that should be inspected
during and after fill construction (Administrative Record No. WV-1008).
In the absence of any clear congressional intent, OSM evaluated
this amendment by comparing the advantages and disadvantages of
locating surface water diversions off of-and-on fills from a public
safety and environmental standpoint. The perimeter or groin channels
required under the Federal rules would likely result in a larger
disturbed area, greater instability of the natural slope adjacent to
the fill and require more long-term maintenance when compared to
surface water diversions located on the fill itself. However, surface
diversions located off the fill are less likely to result in erosion
and in surface water infiltration to the fill mass than are diversions
located on the fill.
Weighing the advantages and shortcomings of both methods of
diversion construction, the Director concludes that neither method is
clearly more environmentally preferable than the other. Therefore, the
Director finds proposed subsection 14.14(g)(8) to be no less effective
than 30 CFR 816/817.73(f) and he is approving it.
D. CSR Sec. 38-2-14.14(g)(11) Sediment Control
WVDEP proposes to add a new provision which states that additional
storage capacity or sediment control measures may be required through
permit revision if sediment removal during operation and construction
of the fill is found to be deficient to the point that significant non-
compliance with applicable effluent limits and water quality standards
results. In support of this amendment WVDEP stated that the term
``significant'' refers to the NPDES permit and enforcement thereof and
that any failure to meet effluent limits constitutes a violation and a
notice of non-compliance is issued (Administrative Record No. WV-934).
The proposed subsection has no Federal counterpart. However, it is
consistent with 30 CFR 816/817.71(a)(1) which requires that excess
spoil be placed in designated disposal areas in a manner to minimize
the adverse affects of leachate and surface water runoff from the fill
on surface and ground waters. The Director is hereby approving
subsection 14.14(g)(11).
E. CSR Sec. 38-2-14.14(g)(12) Prohibited Materials
WVDEP proposes to add a provision which sets forth the materials
that can not be placed, deposited, or disposed of in a durable rock
fill or durable rock fill area. These prohibited materials include
surface soils except for surface soils used to establish vegetation or
surface soils placed in the fill if accounted for in design and
construction as nondurable materials and not placed in critical zones.
Other prohibited materials are mud, silt, or sediment; vegetation or
organic materials; non-coal wastes; and coal refuse. There is no
similar listing of materials prohibited from placement in durable rock
fills in the Federal rules. However, 30 CFR 816/817.73(b) does require
that at least 80 percent of the material in a fill be non-acid and non-
toxic-forming rock; 30 CFR 816/817.71(e) requires the removal of all
vegetation and organic materials from the disposal area prior to
placement of excess spoil; and 30 CFR 816/817.89(b) requires the final
disposal and noncoal waste in a designated disposal site in the permit
area or a
[[Page 42440]]
State approved solid waste disposal area. Furthermore, 30 CFR 816/
817.71(i) provides for the disposal of coal mine waste in excess spoil
fills if approved by the regulatory authority and certain conditions
are met. Since West Virginia's proposal does not allow placement in
durable rock fills of any material that is prohibited by the Federal
regulations, the Director finds that subsection 14.14(g)(12) is no less
effective than the Federal rules and he is hereby approving it.
IV. Summary and Disposition of Comments
Public Comments
The Director solicited public comments and provided an opportunity
for public hearings on the proposed amendment. A public hearing was
held on September 7, 1993, and a public meeting was held on October 27,
1994 (Administrative Records Nos. WV-906 and WV-958). Comments on
durable rock fills were received from GAI Consultants, Inc; Hobet
Mining; Terra Engineers, Inc.; West Virginia Mining and Reclamation
Association; West Virginia Coal Association; West Virginia Highlands
Conservancy; Pine Ridge Coal Corporation; Burko Resources and Eastern
Association Coal Corporation.
All comments received pertain to the drainage control provisions in
CSR Sec. 38-2-14.14(g)(8) as first submitted to OSM on July 30, 1993,
and revised on September 1, 1994 (Administrative Record Nos. WV-893 and
WV-937). In the July 30, 1993, submission, WVDEP proposed to delete the
existing requirement that runoff from areas above and adjacent to
durable rock fills be prohibited from flowing onto the fill and to add
new language requiring diversions to be designed and constructed to
pass runoff ``around and through the fill.'' This language was revised
on September 1, 1994, to read ``around or through the fill.'' OSM
objected to the design and construction of durable rock fills where
surface water runoff would be allowed to be diverted ``through the
fill''. However, all public comments received were in support of this
provision. OSM, State and industry representatives met and developed
new language tentatively acceptable to all parties. This was submitted
to OSM on May 16, 1995 (Administrative Record No. WV-979B). When OSM
reopened the public comment period on July 5, 1995, only one comment
was received on proposed CSR Sec. 38-2-14.14(g)(8) which had been
revised to allow drainage diversion channels to be located anywhere,
including on the fill itself, so long as the channels were designed and
constructed to ensure the stability of the fill, control erosion, and
minimize water infiltration into the fill. In the following section,
OSM is responding to all comments received, including those submitted
in response to WVDEP's July 30, 1993, and September 1, 1994, proposals,
even though these proposals were subsequently revised on May 16, 1995.
History of durable rock performance: Commenters reported that
numerous (up to about 4,000) excess spoil fills (including durable rock
fills) have been constructed in West Virginia over the past 20 to 25
years. Many of these are durable rock fills. According to commenters,
there are no documented massive or structural failures among the fills.
Commenters reported that problems identified have been minor and not
unique to subsurface or center drains. The results of a 1994 WVDEP
survey of fills revealed no substantive difference in structural
integrity among fills with different runoff diversion systems. One
commenter's review of recent (1990-94) citizens' complaints and WVDEP
and OSM inspection reports (July 1993-June 1994) supported the apparent
lack of failures or significant problems with existing fills and fills
under construction in the state.
In response, OSM notes that the similarity of earlier excess spoil
disposal practices in West Virginia to the present is uncertain. The
oldest fills in West Virginia are much smaller than many of those
currently under construction, are primarily of the lift type and are
influenced by smaller drainage areas. The more recent fills of up to
100,000,000 cubic yards have yet to stand the test of time, are
constructed by end-dumping methods, and would typically experience
significant runoff discharges from larger drainage areas. Moreover,
durable rock fills may experience a greater runoff/sediment influx due
to the larger upslope disturbed area found at modern-day mining
operations. The WVDEP survey, and the review of inspection records and
citizens' complaints would not necessarily reveal long-term subsurface
problems. OSM is unaware of any attempts to revisit sites of durable
rock fills that are beyond bond release. Therefore, the comparisons
drawn by commenters between earlier head-of-hollow fills and present-
day durable rock fills have limited value.
Commenters cited evidence for the efficacy and safety of drainage
systems on fills based on their successful use on abandoned-mine-land
(AML) sites. A direct comparison of diversions on AML coal refuse
projects and active excess spoil disposal areas is not possible. AML
project drainage control design options are very limited since fills
are in-place and site conditions may not be suitable for diversion in
natural ground. Excess spoil disposal designs provide greater
flexibility since the fill location can be selected and the fill
material has not yet been placed. Surface water diversions on AML
projects often involve linings of concrete, grouted rip rap, or other
less pervious material which minimize surface drainage infiltration
into the fill mass. Rarely do mine operators line channels in a similar
manner.
Future stability of durable rock fills: One commenter expressed
hope that ``* * * future generations will put these fills to good use
and will maintain surface drainage.'' The objective of the Federal and
State rules on excess spoil design and construction is to promote
permanent stability for the long term protection of the environment,
life, and safety of future generations. The question of permanent
stability is a fundamental issue affecting OSM's concerns about
subsurface and center drains. Destabilizing subsurface processes such
as piping, plugging, and pore-water pressure build-up can take place
over long periods of time without being expressed on the surface. A key
aspect underscoring this concern is the absence of any fill maintenance
following bond release.
Some commenters contended that problems with fill stability are
likely to appear during, and are limited to, the period of
construction. They claimed that, during construction, fill and
foundation-soil consolidation is incomplete; much of the non-durable
rock will already have degraded; the outslope is at the angle of repose
(i.e. not yet graded to a more stable configuration); and, sediment
production is greater than it will be when revegetation becomes
established. Problems stemming from inadequate drainage and a rising
phreatic surface or free-water elevation will also occur soon enough to
be detected and remediated. One commenter also pointed out that future
fill failures, if and when they take place, will be limited to slumping
of fill material into a more stable configuration. The commenter said
that, under steep-slope and poor foundation conditions, flow slides
would not occur, since one should not expect liquefaction in drained
rock-fill material.
Presently, there is very little use and maintenance of finished
excess spoil fills. The postmining land use for approximately 95 per
cent of the fills is forest. Future utilization of land downstream of
some fills in the form of housing developments, farming, park
[[Page 42441]]
grounds, industrial facilities, etc. is possible. However, there is no
reason to assume that those using the land will have the knowledge or
resources available to address problems that may develop or to perform
needed maintenance. What maintenance will occur will partly depend on
what will be observed. Problems with surface drainage systems are
readily noticeable. This is not true for subsurface drains. Since OSM
cannot assume that future generations will assume the liability for
diversion maintenance, conservative performance standards maximizing
long-term diversion effectiveness are necessary.
There are no guarantees that most fill problems will occur during
construction. The benefits of fill/foundation consolidation and
regrading can be counteracted by increases in the fill-mass weight (by
addition of fill material or moisture during construction); or addition
of moisture after bond release. The claim that degradation will be
limited to the time of durable-rock-fill construction lacks supporting
data. Forces working within the fill during consolidation, and action
of water within the fill, can further degrade the fill following
construction. Sediment entering internal drainage systems may not be
adequately controlled by the amount of vegetation on the fill or mine-
site surface following bond release. Sites of natural landslides are
commonly considered to be prone to additional slides. The same can be
said for initial slumps or slides on a constructed fill. Also, even
limited or local slumps could result in more than limited consequences,
depending on the concurrent usage of the site. Finally, whether or not
massive flow slides will occur will depend on moisture conditions in
the fill and long-term strength characteristics of the material. It can
take a long time for steady-state seepage levels to occur. Thus, the
effects of piping, plugging, and rising pore-water pressure may occur
well beyond bond release.
Perimeter drainage channels: Several commenters in support of
center and subsurface drains for surface runoff control emphasized
disadvantages associated with perimeter diversion ditches. Some
commenters cited the effects of geologic degradation (weathering and
erosion of materials in the channels, filling of the channels from
landslides or slumps from adjacent steep slopes); seepage of surface
water into the fill mass through underlying colluvium; and, the
difficulty in achieving effective positive drainage in very long
diversion ditches. Some commenters stated that OSM Directive TSR-6
(Transmittal Number 400, November 10, 1987), which allows perimeter
ditches to be in contact with the fill mass, enhances differential
settlement and erosion.
One commenter noted the annual maintenance requirements of
perimeter ditches around coal refuse embankments as justification for
channels on the fill mass. Another compared fills constructed with
perimeter drains to those using center drains, claiming that the former
fill type experiences more problems with erosion and water penetration
into the fill mass.
OSM concurs that perimeter ditches--and other kinds of drainage
diversion ditches--can and, in fact, do have maintenance problems.
However, the problems are commonly the result of inadequate site
investigation, design, or construction and not necessarily an inherent
condition of all surface drains. Proper investigation of the proposed
diversion location, careful planning and design, along with careful
construction should alleviate many problems commonly encountered in the
field. As for problems that may not be avoided over the long term
(geologic degradation), surface drains still have an important
advantage over subsurface drains since problems can be easily detected
as they develop. Where a site investigation predicts the establishment
of an effective surface drainage system to be prohibitively difficult,
rejection of the site may be the best course of action.
OSM Directive TSR-6 permits contact between perimeter drainage
channels and fill material. While there is some potential for
differential settlement beneath interface channels, OSM does not agree
that the risk of this happening is greater than for center drains. The
thickness of fill material below the center channel is much greater,
and assuming the fill material behaves homogeneously during
consolidation, this location is more susceptible to differential
settlement than interface diversion channels. Furthermore, center-
channel failure could result in more erosion of the fill simply because
there is more fill above natural ground at this location than beneath
the interface channel. These concerns highlight the importance of
design and construction methods that ensure long-term channel stability
and mitigate erosion and water penetration into the fill mass.
Center drainage channels: Two commenters claimed that significant
amounts of seepage into the fill mass should not occur from surface
water flowing in center drains. One commenter claimed to have observed
standing water in center drains as evidence that infiltration was not
occurring. Another maintained that, barring barriers to free drainage,
infiltration will always be less than the drainage capacity in a dumped
rock fill, especially due to the compaction of near-surface materials
during construction. The latter commenter further suggested that ``. .
. infiltration from the ditch could be minimized by means of a
compacted zone of well-graded rockfill in which the voids are
completely choked with rock fines.''
OSM's position, in approval of this amendment, is that center
drains are conditionally acceptable. It must be pointed out that
barriers to free drainage in a constructed channel are difficult to
avoid. Because durable rockfill construction is typified by less-
permeable fine material in the upper reaches of the fill mass, OSM
agrees that a potentially workable method for minimizing seepage from a
center channel is the construction of a compacted zone of well-graded
rockfill.
Subsurface drainage systems: One commenter cited the results of his
flow-through model study in support of the State's original proposal
for surface drainage through fills which was subsequently withdrawn
from further consideration. The commenter concluded that the laboratory
bench-scale test proved that a durable rock fill is capable of
internally passing 24-hour, 100-year storm events. The commenter stated
that a draw-down of water level occurred in the model as flow
approached the toe of the simulated fill. The commenter also pointed
out that flow through rock voids seldom exceeds three feet per second
but can reach many times this value in surface perimeter ditches. Some
commenters have argued against the potential occurrence of plugging in
the subsurface drains by claiming that the end-dumping method produces
a graded fill that effectively prevents migration of fines. One
commenter emphasized the general absence of evidence for plugging,
stating that an autopsy of the simulated durable rock fill found only
rock dust covering the rock particles and/or a minor accumulation of
fines in the bottom of the fill. The commenter stated that there was no
evidence that ``* * * fines tended to migrate through the fill.''
Finally, the commenter suggested that fills with internal drains may
have the potential effect of flood mitigation via runoff attenuation.
The commenter stated that the model outflow was ``* * * a lot less than
the peak into it.''
The commenter also responded to OSM's (September-December 1993)
reviews of the model study. The reviews
[[Page 42442]]
concentrated on comparing the model with actual durable rock fills
constructed in the field. The commenter asserted that the model was
sufficiently representative of real-life fills with respect to its
materials, void ratio, particle gradation, and scale. The commenter
also disputed the OSM contention that durable rock fills have yet to be
tested by a 24-hour, 100-year storm event. The commenter stated that
the 1977 flood ``* * * generally recognized as a 100-year event over
much of Southern West Virginia;'' the 1985 flood over eastern and
central West Virginia ``* * * considered to be 500+ year event;'' and,
localized storms ``* * * equal to or greater than the 100 year 24 hour
storm.''
Again, OSM's position on routing surface runoff through subsurface
drains is based on the potential, long-term and not-readily-observed
effects of piping and plugging. Furthermore, it would appear that the
rock dust and minor sediment accumulation in the simulated fill could
not have occurred without migration of fine material. The model may not
represent actual conditions with respect to fine material. The position
that the end-dumping method prevents fines migration by producing a
graded fill is conceptually feasible, but scientifically undocumented.
The comments pertaining to precipitation events in West Virginia
are at variance with available data. Construction of the earliest West
Virginia durable-rock fills commenced around 1980. Hourly data recorded
at stations throughout West Virginia since 1980 do not show a 100-year,
24-hour event nor multiples of such events. Also, the suggestion that
routing surface runoff into subsurface drains may have a mitigating
effect on floods should create as much concern as it might portend a
potential advantage. Retained water increases the weight of a fill
mass, potentially increasing the driving force for sliding, and may
engender sufficient pore water pressures to reduce the fill's
resistance to failure.
Previous studies: Some comments included references to literature
that the commenter believed supports routing surface runoff through
subsurface drains. These include: the U.S. Department of Agriculture
Soil Conservation Service Engineering Handbook; WVDEP Mining and
Reclamation Handbook; OSM Engineering and Design Manual for Disposal of
Excess Spoil (1983); recommendations of the Durable Rockfill Committee
(1983); 1981 National Academy of Science report; Department of Energy
study by Skelly and Loy on excess-spoil disposal in the watersheds of
Buffalo Creek, Logan County; several issues of Green Lands Magazine;
and ``Embankment-Dam Engineering'' by Casagrande in 1973.
The commenters also reference a 1984 OSM drilling project
investigating fills placed in greater than four-foot lifts that
reported high calculated factors of safety (2.2-2.5) for these types of
fills. Another OSM project mentioned by a commenter is the Crown City
Mining Company experimental practice of single-lift fills with
structural faces in Gallia and Lawrence Counties, Ohio. According to
the commenter, this was reported to be a ``short term success.''
OSM has evaluated the above references and concluded that they do
not specifically promote or support the diversion of surface runoff
into subsurface drainage systems in durable rock fills. The fills that
were drilled by OSM in 1984 were placed in multiple lifts--a practice
not comparable to end-dumping methods being considered in this
rulemaking. The results of the experimental practice in Ohio are not
applicable because the fills involved placement of durable rock in a
non-steep-slope area and there was no routing of runoff through the
fill.
Design flexibility: Several proponents of routing surface runoff
into subsurface and center drains have contended that a mine operator
needs regulatory flexibility in order to design durable-rock-fill
drainage systems appropriate to site-specific conditions. A commenter
suggested that the requirement for fills to be designed by a
professional engineer experienced with earth and rock fills should be a
sufficient safeguard. Commenters said that detailed requirements, or
the insistence that a specified ``recipe'' be followed, result in
unnecessary costs to the mining industry and an impediment to the
development of design improvements.
In response, OSM notes that the only restriction at issue concerns
the use of subsurface drains for surface runoff control in durable-rock
excess spoil fills. Proposed CSR Sec. 38-2-14.14(g)(8) requires that
the fill be designed and constructed with diversion channels that
minimize surface water infiltration into the fill. Therefore, the
diversion of surface runoff into subsurface drains is prohibited. OSM
finds that if this condition is met the proposed rule allows adequate
flexibility for the engineer to design a drainage control system that
fits site-specific conditions.
Federal Agency Comments
Pursuant to section 503(b)(1) of SMCRA and 30 CFR 732.17(h)(11)(i),
OSM solicited comments on the proposed amendment from various Federal
agencies with an actual or potential interest in the West Virginia
program on four different occasions (Administrative Record Nos. WV-891,
WV-897, WV-936, and WV-942). Comments were received from the U.S.
Bureau of Land Management, the Mine Safety and Health Administration,
the U.S. Bureau of Mines, and the U.S. Army Corps of Engineers. These
Federal agencies acknowledged receipt of the amendment, but generally
had no comment or acknowledged that the revisions were satisfactory.
Environmental Protection Agency (EPA)
Pursuant to 30 CFR 732.17(h)(11)(ii), OSM is required to obtain the
written concurrence of the EPA with respect to those provisions of the
proposed program amendment that relate to air or water quality
standards promulgated under the authority of the Clean Water Act (33
U.S.C. 1251 et seq.) or the Clean Air Act (42 U.S.C. 7401 et seq.).
On July 2 and August 3, 1993 (Administrative Record Nos. WV-892 and
WV-896), OSM solicited EPA's concurrence with the proposed amendment.
On October 17, 1994 (Administrative Record No. WV-949), EPA gave its
written concurrence with a condition based on subsection 5.4(b)(4) of
West Virginia's regulations. This condition does not pertain to durable
rock fills which are the subject of this rulemaking.
Pursuant to 30 CFR 732.17(h)(11)(i), the Director solicited
comments on the proposed amendment from EPA on four different occasions
in 1993 and 1994 (Administrative Record Nos. WV-891, WV-897, WV-936,
and WV-942). No comments were received concerning durable rock fills.
V. Director's Decision
Based on the above findings, the Director is approving the proposed
amendment pertaining to durable rock fills as submitted by West
Virginia on July 30, 1993, and revised on September 1, 1994 and May 16,
1995.
The Federal regulations at 30 CFR Part 948 codifying decisions
concerning the West Virginia program are being amended to implement
this decision. This final rule is being made effective immediately to
expedite the State program amendment process and to encourage States to
bring their programs into conformity with the Federal standards without
undue delay. Consistency of State and Federal standards is required by
SMCRA.
[[Page 42443]]
VI. Procedural Determinations
Executive Order 12866
This rule is exempted from review by the Office of Management and
Budget (OMB) under Executive Order 12866 (Regulatory Planning and
Review).
Executive Order 12778
The Department of the Interior has conducted the reviews required
by section 2 of Executive Order 12778 (Civil Justice Reform) and has
determined that, to the extent allowed by law, this rule meets the
applicable standards of subsections (a) and (b) of that section.
However, these standards are not applicable to the actual language of
State regulatory programs and program amendments since each such
program is drafted and promulgated by a specific State, not by OSM.
Under sections 503 and 505 of SMCRA (30 U.S.C. 1253 and 1255) and 30
CFR 730.11, 732.15 and 732.17(h)(10), decisions on proposed State
regulatory programs and program amendments submitted by the States must
be based solely on a determination of whether the submittal is
consistent with SMCRA and its implementing Federal regulations and
whether the other requirements of 30 CFR Parts 730, 731, and 732 have
been met.
National Environmental Policy Act
No environmental impact statement is required for this rule since
section 702(d) of SMCRA [30 U.S.C. 1292(d)] provides that agency
decisions on proposed State regulatory program provisions do not
constitute major Federal actions within the meaning of section
102(2)(C) of the National Environmental Policy Act (42 U.S.C.
4332(2)(C)).
Paperwork Reduction Act
This rule does not contain information collection requirements that
require approval by OMB under the Paperwork Reduction Act (44 U.S.C.
3507 et seq.).
Regulatory Flexibility Act
The Department of the Interior has determined that this rule will
not have a significant economic impact on a substantial number of small
entities under the Regulatory Flexibility Act (5 U.S.C. 601 et seq.).
The State submittal which is the subject of this rule is based upon
counterpart Federal regulations for which an economic analysis was
prepared and certification made that such regulations would not have a
significant economic effect upon a substantial number of small
entities. Accordingly, this rule will ensure that existing requirements
previously promulgated by OSM will be implemented by the State. In
making the determination as to whether this rule would have a
significant economic impact, the Department relied upon the data and
assumptions for the counterpart Federal regulations.
List of Subjects in 30 CFR Part 948
Intergovernmental relations, Surface mining, Underground mining.
Dated: August 10, 1995.
Michael K. Robinson,
Acting Regional Director, Appalachian Regional Coordinating Center.
For the reasons set out in the preamble, Title 30, Chapter VII,
Subchapter T of the Code of Federal Regulations is amended as set forth
below:
PART 948--WEST VIRGINIA
1. The authority citation for Part 948 continues to read as
follows:
Authority: 30 U.S.C. 1201 et seq.
2. Section 948.15 is amended by adding paragraph (n) to read:
Sec. 948.15 Approval of regulatory program amendments.
* * * * *
(n) The sections of the amendment submitted by West Virginia to OSM
by letter dated July 30, 1993, as revised by submittals dated September
1, 1994, and May 16, 1995, pertaining to durable rock fills are
approved effective August 16, 1995.
[FR Doc. 95-20272 Filed 8-15-95; 8:45 am]
BILLING CODE 4310-05-M
