405 KAR 18:190.
Backfilling and grading.
RELATES TO: KRS
350.020, 350.093, 350.100, 350.151, 350.405, 350.410, 350.450, 350.465, 30
C.F.R. Parts 730-733, 735, 817.102-.106, 917, 30 U.S.C. 1253, 1255, 1266
STATUTORY AUTHORITY:
KRS Chapter 13A, 350.028, 350.100, 350.151, 350.465, 30 C.F.R. Parts 730-733,
735, 817.102-.106, 917, 30 U.S.C. 1253, 1255, 1266
NECESSITY, FUNCTION,
AND CONFORMITY: KRS Chapter 350 in pertinent part requires the cabinet to
promulgate rules and administrative regulations establishing performance
standards for protection of people and property, land, water and other natural
resources, and aesthetic values, during underground mining activities and for
restoration and reclamation of surface areas affected by underground mining
activities. This administrative regulation sets forth requirements for
backfilling and grading of areas affected by surface operations, including
requirements for backfilling and grading of face-up areas and other cut slopes
and limited exemptions, timing of backfilling and grading, covering coal and
acid and toxic materials, and regrading or stabilizing rills and gullies.
Section 1. Timing of
Backfilling and Grading. Surface areas disturbed incident to underground mining
activities shall be backfilled and graded in accordance with a relative
time-schedule approved by the cabinet in accordance with 405 KAR 18:020.
Section 2. General
Backfilling and Grading Requirements. (1) Except as provided in subsection (8)
of this section, all disturbed areas shall be returned to their approximate
original contour. All spoil shall be transported, placed in a controlled
manner, backfilled, compacted (where advisable to ensure stability or to
prevent leaching of toxic materials), and graded to:
(a) Eliminate all
highwalls (except as otherwise provided in Section 5 of this administrative
regulation), spoil piles, and depressions (excluding depressions and
impoundments approved pursuant to subsection (4) or (5) of this section);
(b) Ensure a
long-term static factor of safety of at least one and three-tenths (1.3) for
all portions of the reclaimed land;
(c) Achieve a
postmining slope which does not exceed the angle of repose and which does
prevent slides;
(d) Minimize erosion
and adverse effects on surface and groundwater both on and off the site; and
(e) Support the
approved postmining land use.
(2) Spoil, except
excess spoil disposed of in accordance with 405 KAR 18:130, shall be returned
to the excavated surface areas.
(3) Disposal of coal
processing waste and underground development waste in the mined-out surface
area shall be in accordance with 405 KAR 18:140, except that a long-term static
safety factor of one and three-tenths (1.3) shall be achieved.
(4) Small
depressions may be constructed on backfilled areas, if the depressions:
(a) Are needed to
minimize erosion, conserve soil moisture, create or enhance wildlife habitat,
or promote vegetation;
(b) Are not
disapproved by the cabinet;
(c) Are not
substitutes for compliance with approximate original contour requirements;
(d) Do not adversely
affect the stability of the backfilled area; and
(e) Are not located
on steep-slope outslopes.
(5) Impoundments on
backfilled areas may be approved, if the impoundments:
(a) Meet the
applicable requirements of 405 KAR 18:060, Section 10 and 405 KAR 18:100;
(b) Are
demonstrated, to the satisfaction of the cabinet in the permit application, to
have no adverse effect on the stability of the backfilled area;
(c) Are consistent
with and suitable for the approved postmining land use;
(d) Are specifically
approved by the cabinet in the permit application; and
(e) Are not located
on steep-slope outslopes.
(6) All underground
mining activities on slopes above twenty (20) degrees, or on lesser slopes that
the cabinet defines as steep slopes, shall comply with the requirements of 405
KAR 20:060.
(7) All final
grading; preparation of overburden before replacement of topsoil, topsoil
substitutes, and topsoil supplements; and placement of topsoil, topsoil
substitutes, and topsoil supplements shall be done along the contour to
minimize subsequent erosion and instability. If grading, preparation, or
placement along the contour is hazardous to equipment operators, then grading,
preparation, or placement in a direction other than generally parallel to the
contour may be used. In all cases, grading, preparation, and placement shall be
conducted in a manner which minimizes erosion and provides a surface for
placement of topsoil, topsoil substitutes, and topsoil supplements which will
minimize slippage.
(8) The postmining
slope may vary from the approximate original contour if approval is obtained
from the cabinet for:
(a) A variance from
approximate original contour requirements in accordance with 405 KAR 8:050,
Section 6;
(b) Incomplete elimination
of highwalls in previously mined areas in accordance with Section 5 of this
administrative regulation; or
(c) Incomplete
elimination of face-up areas and similar cut slopes pursuant to subsection (9)
of this section.
(9) Face-up areas
and similar cut slopes created prior to the effective date of SMCRA, as defined
at Section 502(a), (b), and (c) therein, that are associated with underground
mining activities which were started prior to the effective date of SMCRA and
which have continued as existing and ongoing operations pursuant to permits
issued under the interim and permanent regulatory programs shall be backfilled
and graded in accordance with the requirements of Section 5 of this administrative
regulation; except that for the purposes of this subsection "reasonably
available spoil" shall not include spoil generated by the operation prior
to the effective date of SMCRA which is not accessible and available for use or
which would cause a hazard to public safety or significant damage to the environment
if rehandled.
Section 3. Disposal
of Acid-forming, Toxic-forming, and Combustible Materials and Coverage of Coal
Seams. (1) General. Exposed coal seams, acid-forming materials, toxic-forming
materials, and combustible materials which are used, produced, or exposed
during surface coal mining and reclamation operations shall be handled;
disposed of; treated; and covered with nontoxic-forming, nonacid-forming, and
noncombustible materials in a manner which:
(a) Minimizes
adverse impacts on surface and groundwater, minimizes disturbances to the
hydrologic balance, and prevents material damage to the hydrologic balance;
(b) Ensures
compliance with 405 KAR 18:060;
(c) Prevents
sustained combustion;
(d) Minimizes
adverse impacts on plant growth and the approved postmining land use;
(e) Ensures that the
affected area is capable of sustaining sufficient vegetation to meet the
revegetation requirements of 405 KAR 18:200; and
(f) Ensures that the
affected area is capable of meeting the postmining land use requirements of 405
KAR 18:220.
(2) Coverage and
treatment. All exposed coal seams, acid-forming materials, toxic-forming
materials, and combustible materials which are used, produced, or exposed
during surface coal mining and reclamation operations shall be covered and
treated as necessary to neutralize toxicity, acidity, and combustibility, in
order to ensure long-term and short-term compliance with subsection (1) of this
section.
(a) All exposed coal
seams shall be covered with a minimum of four (4) feet of nontoxic-forming,
nonacid-forming, and noncombustible materials. The cabinet shall require
thicker amounts of cover, special compaction of cover, treatment, or other
measures as necessary to ensure compliance with subsection (1) of this section
and to prevent exposure of the coal seams by erosion.
(b) Excluding
exposed coal seams, all acid-forming materials, toxic-forming materials, and
combustible materials which are used, produced, or exposed during surface coal
mining and reclamation operations shall be:
1. Selectively
blended with nontoxic-forming, nonacid-forming, and noncombustible materials;
treated; or selectively handled, or an appropriate combination of those
measures shall be used, as necessary to ensure compliance with subsection (1)
of this section; and
2. Covered with a
minimum of four (4) feet of nontoxic-forming, nonacid-forming, and
noncombustible materials. The cabinet shall require thicker amounts of cover,
special compaction of cover, treatment, or other measures as necessary to ensure
compliance with subsection (1) of this section and to prevent exposure of the
toxic-forming, acid-forming, or combustible materials by erosion. The cabinet
may approve lesser amounts of cover, or no cover (other than topsoil, topsoil
substitutes, or topsoil supplements), if the applicant demonstrates, to the
satisfaction of the cabinet in the permit application, that the lesser amounts
are sufficient to ensure compliance with subsection (1) of this section and to
maintain coverage of the toxic-forming, acid-forming, and combustible
materials;
3. If required or
approved by the cabinet, compacted and placed in an environment which minimizes
the oxidation potential of the toxic-forming materials, acid-forming materials,
and combustible materials; and
4. If required or
approved by the cabinet, disposed so as to minimize surface and groundwater
contact with acid-forming materials, toxic-forming materials, and combustible
materials. Water contact may be minimized by the encasement of those materials
in low-permeability substances and by the compaction and selective placement of
those materials in locations other than surface drainage courses, groundwater
recharge areas, or areas of significant groundwater flow. As an alternative to
minimizing contact with surface and groundwater and if feasible based on site
conditions, the cabinet may allow acid-forming materials, toxic-forming
materials, and combustible materials be placed below the permanent water table.
(3) The cabinet
shall require measures in addition to those identified in subsection (2) of
this section if necessary to ensure protection of the environment or the health
or safety of the public.
Section 4. Regrading
or Stabilizing Rills and Gullies. Except as provided in subsections (1) and (2)
of this section, if rills or gullies deeper than nine (9) inches form in areas
that have been regraded and topsoiled, the rills and gullies shall be filled,
graded, or otherwise stabilized and the area reseeded and replanted according
to 405 KAR 18:200.
(1) Rills or gullies
less than nine (9) inches deep shall be stabilized and the area reseeded and
replanted, if the rills or gullies are disruptive to the approved postmining
land use or to the establishment of vegetation, may result in additional
erosion and sedimentation, or may cause or contribute to the violation of a
water quality standard.
(2) Rills and
gullies deeper than nine (9) inches need not be filled, regraded, and
revegetated if all of the following criteria are met:
(a) They are incised
to solid bedrock or are otherwise stable and not likely to further erode;
(b) They are not
disruptive to the approved postmining land use or to the establishment of the
vegetative cover; and
(c) They neither
cause nor contribute to the violation of water quality standards.
Section 5. Remining
Previously Mined Areas. (1) General requirements. Remining operations on
previously mined areas, including steep slope areas, that contain a preexisting
highwall shall comply with Sections 1 through 4 of this administrative regulation
except as provided in this section.
(2) Variances to
backfilling and grading requirements for remining operations. The requirements
within Section 2(1)(a) of this administrative regulation to completely
eliminate highwalls shall apply to remining operations, except for situations
in which the volume of all reasonably available spoil is demonstrated, to the
satisfaction of the cabinet in the permit application, to be insufficient to
completely backfill and eliminate the preexisting or modified highwall. The
highwall shall be eliminated to the maximum extent technically practicable in
accordance with the following criteria:
(a) All reasonably
available spoil shall be used to backfill the area.
(b) The backfill
shall be graded to a slope which is compatible with the approved postmining
land use and which provides adequate drainage and long-term stability (one and
three-tenths (1.3) long-term static factor of safety). The exposed coal seam
shall be covered in accordance with Section 3 of this administrative regulation.
(c) Spoil generated
or handled by the remining operation shall not be placed on the fill section of
any existing or new bench.
(d) Any highwall
remnant shall be stable and not pose a hazard to the public health and safety
or to the environment. The permittee shall demonstrate, to the satisfaction of
the cabinet in the permit application, that the postmining highwall remnant
will be stable. If the highwall remnant is determined by the cabinet to be
unstable or potentially unstable, the permittee shall perform any corrective
measures required by the cabinet to stabilize the highwall remnant.
(e) Spoil placed on
the outslope during previous mining operations shall not be disturbed if the
disturbance will cause instability of the remaining spoil or otherwise increase
the hazard to the public health or safety or to the environment.
Section 6. Temporary
Storage of Materials. (1) After excavation, materials to be used for
backfilling in compliance with this administrative regulation shall be
returned, for backfilling purposes in accordance with this administrative
regulation, to a mined-out area within the permit area or shall be temporarily
stored in designated storage areas designs of which have been provided in the
permit application and thereby approved by the cabinet.
(2) Temporary
storage areas shall be designed and constructed in accordance with the
requirements of 405 KAR 18:130 or 405 KAR 18:140, depending on the type of
material, except as specified in the following:
(a) If the temporary
storage area is to exist for six (6) months or longer, the storage area shall
be protected by establishment of an effective cover of nonnoxious,
quick-growing, annual and perennial plants seeded or planted during the first
normal seeding or planting period following placement of the fill material and
resown as necessary thereafter.
(b) Topsoil, topsoil
substitute, and topsoil supplement materials to be used in final reclamation of
the temporary storage area shall either be stockpiled in accordance with 405
KAR 18:050, Section 3(1) through (3) or temporarily redistributed on areas in
accordance with 405 KAR 18:050, Section 3(4). The applicant shall submit, in
the permit application, a discussion from a qualified soil scientist or
qualified agronomist which indicates, to the satisfaction of the cabinet, that
the topsoil stockpile or temporary redistribution plan will minimize adverse
effects on the quality and quantity of the topsoil, topsoil substitute, and
topsoil supplement materials.
(3) Fills designed
and constructed in accordance with this section may be retained as permanent
structures if:
(a) The cabinet
approves a permit revision submitted in accordance with 405 KAR 8:010, Section
20 for retention of the fill as a permanent structure and for the use of
alternate materials to backfill areas and return the disturbed areas to their
approximate original contour, in accordance with the requirements of this
administrative regulation;
(b) Topsoil, topsoil
substitute, and topsoil supplement materials are redistributed on the fill in
accordance with 405 KAR 18:050;
(c) The fill is
revegetated and reclaimed in accordance with 405 KAR 18:200, 405 KAR 18:220,
and all other applicable requirements of KRS Chapter 350 and 405 KAR; and
(d) The borrow area
or other area from which the alternate backfill material is obtained is
permitted under a valid permit from Department for Natural Resources and is
reclaimed in accordance with the requirements of KRS Chapter 350 and 405 KAR.
(8 Ky.R. 1578; eff. 1-6-83; Am. 10 Ky.R. 824; eff. 4-23-84; 12 Ky.R. 951; 1332;
eff. 2-4-86; 13 Ky.R. 1891; eff. 7-2-87; 15 Ky.R. 498; 1089; eff. 12-13-88; 18
Ky.R. 438; 1877; eff. 11-26-91; TAm eff. 8-9-2007.)
